Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | * CFQ, or complete fairness queueing, disk scheduler. |
| 3 | * |
| 4 | * Based on ideas from a previously unfinished io |
| 5 | * scheduler (round robin per-process disk scheduling) and Andrea Arcangeli. |
| 6 | * |
Jens Axboe | 0fe2347 | 2006-09-04 15:41:16 +0200 | [diff] [blame] | 7 | * Copyright (C) 2003 Jens Axboe <axboe@kernel.dk> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 8 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 9 | #include <linux/module.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 10 | #include <linux/slab.h> |
Al Viro | 1cc9be6 | 2006-03-18 12:29:52 -0500 | [diff] [blame] | 11 | #include <linux/blkdev.h> |
| 12 | #include <linux/elevator.h> |
Randy Dunlap | ad5ebd2 | 2009-11-11 13:47:45 +0100 | [diff] [blame] | 13 | #include <linux/jiffies.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | #include <linux/rbtree.h> |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 15 | #include <linux/ioprio.h> |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 16 | #include <linux/blktrace_api.h> |
Tejun Heo | 6e736be | 2011-12-14 00:33:38 +0100 | [diff] [blame] | 17 | #include "blk.h" |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 18 | #include "blk-cgroup.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | |
| 20 | /* |
| 21 | * tunables |
| 22 | */ |
Jens Axboe | fe094d9 | 2008-01-31 13:08:54 +0100 | [diff] [blame] | 23 | /* max queue in one round of service */ |
Shaohua Li | abc3c74 | 2010-03-01 09:20:54 +0100 | [diff] [blame] | 24 | static const int cfq_quantum = 8; |
Arjan van de Ven | 6410009 | 2006-01-06 09:46:02 +0100 | [diff] [blame] | 25 | static const int cfq_fifo_expire[2] = { HZ / 4, HZ / 8 }; |
Jens Axboe | fe094d9 | 2008-01-31 13:08:54 +0100 | [diff] [blame] | 26 | /* maximum backwards seek, in KiB */ |
| 27 | static const int cfq_back_max = 16 * 1024; |
| 28 | /* penalty of a backwards seek */ |
| 29 | static const int cfq_back_penalty = 2; |
Arjan van de Ven | 6410009 | 2006-01-06 09:46:02 +0100 | [diff] [blame] | 30 | static const int cfq_slice_sync = HZ / 10; |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 31 | static int cfq_slice_async = HZ / 25; |
Arjan van de Ven | 6410009 | 2006-01-06 09:46:02 +0100 | [diff] [blame] | 32 | static const int cfq_slice_async_rq = 2; |
Jens Axboe | caaa5f9 | 2006-06-16 11:23:00 +0200 | [diff] [blame] | 33 | static int cfq_slice_idle = HZ / 125; |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 34 | static int cfq_group_idle = HZ / 125; |
Corrado Zoccolo | 5db5d64 | 2009-10-26 22:44:04 +0100 | [diff] [blame] | 35 | static const int cfq_target_latency = HZ * 3/10; /* 300 ms */ |
| 36 | static const int cfq_hist_divisor = 4; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 37 | |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 38 | /* |
Jens Axboe | 0871714 | 2008-01-28 11:38:15 +0100 | [diff] [blame] | 39 | * offset from end of service tree |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 40 | */ |
Jens Axboe | 0871714 | 2008-01-28 11:38:15 +0100 | [diff] [blame] | 41 | #define CFQ_IDLE_DELAY (HZ / 5) |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 42 | |
| 43 | /* |
| 44 | * below this threshold, we consider thinktime immediate |
| 45 | */ |
| 46 | #define CFQ_MIN_TT (2) |
| 47 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 48 | #define CFQ_SLICE_SCALE (5) |
Aaron Carroll | 45333d5 | 2008-08-26 15:52:36 +0200 | [diff] [blame] | 49 | #define CFQ_HW_QUEUE_MIN (5) |
Vivek Goyal | 25bc6b0 | 2009-12-03 12:59:43 -0500 | [diff] [blame] | 50 | #define CFQ_SERVICE_SHIFT 12 |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 51 | |
Corrado Zoccolo | 3dde36d | 2010-02-27 19:45:39 +0100 | [diff] [blame] | 52 | #define CFQQ_SEEK_THR (sector_t)(8 * 100) |
Shaohua Li | e9ce335 | 2010-03-19 08:03:04 +0100 | [diff] [blame] | 53 | #define CFQQ_CLOSE_THR (sector_t)(8 * 1024) |
Corrado Zoccolo | 41647e7 | 2010-02-27 19:45:40 +0100 | [diff] [blame] | 54 | #define CFQQ_SECT_THR_NONROT (sector_t)(2 * 32) |
Corrado Zoccolo | 3dde36d | 2010-02-27 19:45:39 +0100 | [diff] [blame] | 55 | #define CFQQ_SEEKY(cfqq) (hweight32(cfqq->seek_history) > 32/8) |
Shaohua Li | ae54abe | 2010-02-05 13:11:45 +0100 | [diff] [blame] | 56 | |
Tejun Heo | a612fdd | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 57 | #define RQ_CIC(rq) icq_to_cic((rq)->elv.icq) |
| 58 | #define RQ_CFQQ(rq) (struct cfq_queue *) ((rq)->elv.priv[0]) |
| 59 | #define RQ_CFQG(rq) (struct cfq_group *) ((rq)->elv.priv[1]) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | |
Christoph Lameter | e18b890 | 2006-12-06 20:33:20 -0800 | [diff] [blame] | 61 | static struct kmem_cache *cfq_pool; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 63 | #define CFQ_PRIO_LISTS IOPRIO_BE_NR |
| 64 | #define cfq_class_idle(cfqq) ((cfqq)->ioprio_class == IOPRIO_CLASS_IDLE) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 65 | #define cfq_class_rt(cfqq) ((cfqq)->ioprio_class == IOPRIO_CLASS_RT) |
| 66 | |
Jens Axboe | 206dc69 | 2006-03-28 13:03:44 +0200 | [diff] [blame] | 67 | #define sample_valid(samples) ((samples) > 80) |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 68 | #define rb_entry_cfqg(node) rb_entry((node), struct cfq_group, rb_node) |
Jens Axboe | 206dc69 | 2006-03-28 13:03:44 +0200 | [diff] [blame] | 69 | |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 70 | struct cfq_ttime { |
| 71 | unsigned long last_end_request; |
| 72 | |
| 73 | unsigned long ttime_total; |
| 74 | unsigned long ttime_samples; |
| 75 | unsigned long ttime_mean; |
| 76 | }; |
| 77 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 78 | /* |
Jens Axboe | cc09e29 | 2007-04-26 12:53:50 +0200 | [diff] [blame] | 79 | * Most of our rbtree usage is for sorting with min extraction, so |
| 80 | * if we cache the leftmost node we don't have to walk down the tree |
| 81 | * to find it. Idea borrowed from Ingo Molnars CFS scheduler. We should |
| 82 | * move this into the elevator for the rq sorting as well. |
| 83 | */ |
| 84 | struct cfq_rb_root { |
| 85 | struct rb_root rb; |
| 86 | struct rb_node *left; |
Corrado Zoccolo | aa6f6a3 | 2009-10-26 22:44:33 +0100 | [diff] [blame] | 87 | unsigned count; |
Richard Kennedy | 73e9ffd | 2010-03-01 10:50:20 +0100 | [diff] [blame] | 88 | unsigned total_weight; |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 89 | u64 min_vdisktime; |
Shaohua Li | f5f2b6c | 2011-07-12 14:24:55 +0200 | [diff] [blame] | 90 | struct cfq_ttime ttime; |
Jens Axboe | cc09e29 | 2007-04-26 12:53:50 +0200 | [diff] [blame] | 91 | }; |
Shaohua Li | f5f2b6c | 2011-07-12 14:24:55 +0200 | [diff] [blame] | 92 | #define CFQ_RB_ROOT (struct cfq_rb_root) { .rb = RB_ROOT, \ |
| 93 | .ttime = {.last_end_request = jiffies,},} |
Jens Axboe | cc09e29 | 2007-04-26 12:53:50 +0200 | [diff] [blame] | 94 | |
| 95 | /* |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 96 | * Per process-grouping structure |
| 97 | */ |
| 98 | struct cfq_queue { |
| 99 | /* reference count */ |
Shaohua Li | 30d7b94 | 2011-01-07 08:46:59 +0100 | [diff] [blame] | 100 | int ref; |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 101 | /* various state flags, see below */ |
| 102 | unsigned int flags; |
| 103 | /* parent cfq_data */ |
| 104 | struct cfq_data *cfqd; |
| 105 | /* service_tree member */ |
| 106 | struct rb_node rb_node; |
| 107 | /* service_tree key */ |
| 108 | unsigned long rb_key; |
| 109 | /* prio tree member */ |
| 110 | struct rb_node p_node; |
| 111 | /* prio tree root we belong to, if any */ |
| 112 | struct rb_root *p_root; |
| 113 | /* sorted list of pending requests */ |
| 114 | struct rb_root sort_list; |
| 115 | /* if fifo isn't expired, next request to serve */ |
| 116 | struct request *next_rq; |
| 117 | /* requests queued in sort_list */ |
| 118 | int queued[2]; |
| 119 | /* currently allocated requests */ |
| 120 | int allocated[2]; |
| 121 | /* fifo list of requests in sort_list */ |
| 122 | struct list_head fifo; |
| 123 | |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 124 | /* time when queue got scheduled in to dispatch first request. */ |
| 125 | unsigned long dispatch_start; |
Vivek Goyal | f75edf2 | 2009-12-03 12:59:53 -0500 | [diff] [blame] | 126 | unsigned int allocated_slice; |
Richard Kennedy | c4081ba | 2010-02-22 13:49:24 +0100 | [diff] [blame] | 127 | unsigned int slice_dispatch; |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 128 | /* time when first request from queue completed and slice started. */ |
| 129 | unsigned long slice_start; |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 130 | unsigned long slice_end; |
| 131 | long slice_resid; |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 132 | |
Christoph Hellwig | 65299a3 | 2011-08-23 14:50:29 +0200 | [diff] [blame] | 133 | /* pending priority requests */ |
| 134 | int prio_pending; |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 135 | /* number of requests that are on the dispatch list or inside driver */ |
| 136 | int dispatched; |
| 137 | |
| 138 | /* io prio of this group */ |
| 139 | unsigned short ioprio, org_ioprio; |
Justin TerAvest | 4aede84 | 2011-07-12 08:31:45 +0200 | [diff] [blame] | 140 | unsigned short ioprio_class; |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 141 | |
Richard Kennedy | c4081ba | 2010-02-22 13:49:24 +0100 | [diff] [blame] | 142 | pid_t pid; |
| 143 | |
Corrado Zoccolo | 3dde36d | 2010-02-27 19:45:39 +0100 | [diff] [blame] | 144 | u32 seek_history; |
Jeff Moyer | b2c18e1 | 2009-10-23 17:14:49 -0400 | [diff] [blame] | 145 | sector_t last_request_pos; |
| 146 | |
Corrado Zoccolo | aa6f6a3 | 2009-10-26 22:44:33 +0100 | [diff] [blame] | 147 | struct cfq_rb_root *service_tree; |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 148 | struct cfq_queue *new_cfqq; |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 149 | struct cfq_group *cfqg; |
Vivek Goyal | c4e7893 | 2010-08-23 12:25:03 +0200 | [diff] [blame] | 150 | /* Number of sectors dispatched from queue in single dispatch round */ |
| 151 | unsigned long nr_sectors; |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 152 | }; |
| 153 | |
| 154 | /* |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 155 | * First index in the service_trees. |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 156 | * IDLE is handled separately, so it has negative index |
| 157 | */ |
| 158 | enum wl_prio_t { |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 159 | BE_WORKLOAD = 0, |
Vivek Goyal | 615f025 | 2009-12-03 12:59:39 -0500 | [diff] [blame] | 160 | RT_WORKLOAD = 1, |
| 161 | IDLE_WORKLOAD = 2, |
Vivek Goyal | b462732 | 2010-10-22 09:48:43 +0200 | [diff] [blame] | 162 | CFQ_PRIO_NR, |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 163 | }; |
| 164 | |
| 165 | /* |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 166 | * Second index in the service_trees. |
| 167 | */ |
| 168 | enum wl_type_t { |
| 169 | ASYNC_WORKLOAD = 0, |
| 170 | SYNC_NOIDLE_WORKLOAD = 1, |
| 171 | SYNC_WORKLOAD = 2 |
| 172 | }; |
| 173 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 174 | struct cfqg_stats { |
| 175 | #ifdef CONFIG_CFQ_GROUP_IOSCHED |
| 176 | /* total bytes transferred */ |
| 177 | struct blkg_rwstat service_bytes; |
| 178 | /* total IOs serviced, post merge */ |
| 179 | struct blkg_rwstat serviced; |
| 180 | /* number of ios merged */ |
| 181 | struct blkg_rwstat merged; |
| 182 | /* total time spent on device in ns, may not be accurate w/ queueing */ |
| 183 | struct blkg_rwstat service_time; |
| 184 | /* total time spent waiting in scheduler queue in ns */ |
| 185 | struct blkg_rwstat wait_time; |
| 186 | /* number of IOs queued up */ |
| 187 | struct blkg_rwstat queued; |
| 188 | /* total sectors transferred */ |
| 189 | struct blkg_stat sectors; |
| 190 | /* total disk time and nr sectors dispatched by this group */ |
| 191 | struct blkg_stat time; |
| 192 | #ifdef CONFIG_DEBUG_BLK_CGROUP |
| 193 | /* time not charged to this cgroup */ |
| 194 | struct blkg_stat unaccounted_time; |
| 195 | /* sum of number of ios queued across all samples */ |
| 196 | struct blkg_stat avg_queue_size_sum; |
| 197 | /* count of samples taken for average */ |
| 198 | struct blkg_stat avg_queue_size_samples; |
| 199 | /* how many times this group has been removed from service tree */ |
| 200 | struct blkg_stat dequeue; |
| 201 | /* total time spent waiting for it to be assigned a timeslice. */ |
| 202 | struct blkg_stat group_wait_time; |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 203 | /* time spent idling for this blkcg_gq */ |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 204 | struct blkg_stat idle_time; |
| 205 | /* total time with empty current active q with other requests queued */ |
| 206 | struct blkg_stat empty_time; |
| 207 | /* fields after this shouldn't be cleared on stat reset */ |
| 208 | uint64_t start_group_wait_time; |
| 209 | uint64_t start_idle_time; |
| 210 | uint64_t start_empty_time; |
| 211 | uint16_t flags; |
| 212 | #endif /* CONFIG_DEBUG_BLK_CGROUP */ |
| 213 | #endif /* CONFIG_CFQ_GROUP_IOSCHED */ |
| 214 | }; |
| 215 | |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 216 | /* This is per cgroup per device grouping structure */ |
| 217 | struct cfq_group { |
Tejun Heo | f95a04a | 2012-04-16 13:57:26 -0700 | [diff] [blame] | 218 | /* must be the first member */ |
| 219 | struct blkg_policy_data pd; |
| 220 | |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 221 | /* group service_tree member */ |
| 222 | struct rb_node rb_node; |
| 223 | |
| 224 | /* group service_tree key */ |
| 225 | u64 vdisktime; |
Vivek Goyal | 25bc6b0 | 2009-12-03 12:59:43 -0500 | [diff] [blame] | 226 | unsigned int weight; |
Justin TerAvest | 8184f93 | 2011-03-17 16:12:36 +0100 | [diff] [blame] | 227 | unsigned int new_weight; |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 228 | unsigned int dev_weight; |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 229 | |
| 230 | /* number of cfqq currently on this group */ |
| 231 | int nr_cfqq; |
| 232 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 233 | /* |
Kyungmin Park | 4495a7d | 2011-05-31 10:04:09 +0200 | [diff] [blame] | 234 | * Per group busy queues average. Useful for workload slice calc. We |
Vivek Goyal | b462732 | 2010-10-22 09:48:43 +0200 | [diff] [blame] | 235 | * create the array for each prio class but at run time it is used |
| 236 | * only for RT and BE class and slot for IDLE class remains unused. |
| 237 | * This is primarily done to avoid confusion and a gcc warning. |
| 238 | */ |
| 239 | unsigned int busy_queues_avg[CFQ_PRIO_NR]; |
| 240 | /* |
| 241 | * rr lists of queues with requests. We maintain service trees for |
| 242 | * RT and BE classes. These trees are subdivided in subclasses |
| 243 | * of SYNC, SYNC_NOIDLE and ASYNC based on workload type. For IDLE |
| 244 | * class there is no subclassification and all the cfq queues go on |
| 245 | * a single tree service_tree_idle. |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 246 | * Counts are embedded in the cfq_rb_root |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 247 | */ |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 248 | struct cfq_rb_root service_trees[2][3]; |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 249 | struct cfq_rb_root service_tree_idle; |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 250 | |
| 251 | unsigned long saved_workload_slice; |
| 252 | enum wl_type_t saved_workload; |
| 253 | enum wl_prio_t saved_serving_prio; |
Tejun Heo | 4eef304 | 2012-03-05 13:15:18 -0800 | [diff] [blame] | 254 | |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 255 | /* number of requests that are on the dispatch list or inside driver */ |
| 256 | int dispatched; |
Shaohua Li | 7700fc4 | 2011-07-12 14:24:56 +0200 | [diff] [blame] | 257 | struct cfq_ttime ttime; |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 258 | struct cfqg_stats stats; |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 259 | }; |
| 260 | |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 261 | struct cfq_io_cq { |
| 262 | struct io_cq icq; /* must be the first member */ |
| 263 | struct cfq_queue *cfqq[2]; |
| 264 | struct cfq_ttime ttime; |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 265 | int ioprio; /* the current ioprio */ |
| 266 | #ifdef CONFIG_CFQ_GROUP_IOSCHED |
| 267 | uint64_t blkcg_id; /* the current blkcg ID */ |
| 268 | #endif |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 269 | }; |
| 270 | |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 271 | /* |
| 272 | * Per block device queue structure |
| 273 | */ |
| 274 | struct cfq_data { |
| 275 | struct request_queue *queue; |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 276 | /* Root service tree for cfq_groups */ |
| 277 | struct cfq_rb_root grp_service_tree; |
Tejun Heo | f51b802 | 2012-03-05 13:15:05 -0800 | [diff] [blame] | 278 | struct cfq_group *root_group; |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 279 | |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 280 | /* |
| 281 | * The priority currently being served |
| 282 | */ |
| 283 | enum wl_prio_t serving_prio; |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 284 | enum wl_type_t serving_type; |
| 285 | unsigned long workload_expires; |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 286 | struct cfq_group *serving_group; |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 287 | |
| 288 | /* |
| 289 | * Each priority tree is sorted by next_request position. These |
| 290 | * trees are used when determining if two or more queues are |
| 291 | * interleaving requests (see cfq_close_cooperator). |
| 292 | */ |
| 293 | struct rb_root prio_trees[CFQ_PRIO_LISTS]; |
| 294 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 295 | unsigned int busy_queues; |
Shaohua Li | ef8a41d | 2011-03-07 09:26:29 +0100 | [diff] [blame] | 296 | unsigned int busy_sync_queues; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 297 | |
Corrado Zoccolo | 53c583d | 2010-02-28 19:45:05 +0100 | [diff] [blame] | 298 | int rq_in_driver; |
| 299 | int rq_in_flight[2]; |
Aaron Carroll | 45333d5 | 2008-08-26 15:52:36 +0200 | [diff] [blame] | 300 | |
| 301 | /* |
| 302 | * queue-depth detection |
| 303 | */ |
| 304 | int rq_queued; |
Jens Axboe | 25776e3 | 2006-06-01 10:12:26 +0200 | [diff] [blame] | 305 | int hw_tag; |
Corrado Zoccolo | e459dd0 | 2009-11-26 10:02:57 +0100 | [diff] [blame] | 306 | /* |
| 307 | * hw_tag can be |
| 308 | * -1 => indeterminate, (cfq will behave as if NCQ is present, to allow better detection) |
| 309 | * 1 => NCQ is present (hw_tag_est_depth is the estimated max depth) |
| 310 | * 0 => no NCQ |
| 311 | */ |
| 312 | int hw_tag_est_depth; |
| 313 | unsigned int hw_tag_samples; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 314 | |
| 315 | /* |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 316 | * idle window management |
| 317 | */ |
| 318 | struct timer_list idle_slice_timer; |
Jens Axboe | 23e018a | 2009-10-05 08:52:35 +0200 | [diff] [blame] | 319 | struct work_struct unplug_work; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 320 | |
| 321 | struct cfq_queue *active_queue; |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 322 | struct cfq_io_cq *active_cic; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 323 | |
Vasily Tarasov | c2dea2d | 2007-07-20 10:06:38 +0200 | [diff] [blame] | 324 | /* |
| 325 | * async queue for each priority case |
| 326 | */ |
| 327 | struct cfq_queue *async_cfqq[2][IOPRIO_BE_NR]; |
| 328 | struct cfq_queue *async_idle_cfqq; |
Jens Axboe | 15c31be | 2007-07-10 13:43:25 +0200 | [diff] [blame] | 329 | |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 330 | sector_t last_position; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 331 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 332 | /* |
| 333 | * tunables, see top of file |
| 334 | */ |
| 335 | unsigned int cfq_quantum; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 336 | unsigned int cfq_fifo_expire[2]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 337 | unsigned int cfq_back_penalty; |
| 338 | unsigned int cfq_back_max; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 339 | unsigned int cfq_slice[2]; |
| 340 | unsigned int cfq_slice_async_rq; |
| 341 | unsigned int cfq_slice_idle; |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 342 | unsigned int cfq_group_idle; |
Jens Axboe | 963b72f | 2009-10-03 19:42:18 +0200 | [diff] [blame] | 343 | unsigned int cfq_latency; |
Tao Ma | 5bf14c0 | 2012-04-01 14:33:39 -0700 | [diff] [blame] | 344 | unsigned int cfq_target_latency; |
Al Viro | d9ff418 | 2006-03-18 13:51:22 -0500 | [diff] [blame] | 345 | |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 346 | /* |
| 347 | * Fallback dummy cfqq for extreme OOM conditions |
| 348 | */ |
| 349 | struct cfq_queue oom_cfqq; |
Vivek Goyal | 365722b | 2009-10-03 15:21:27 +0200 | [diff] [blame] | 350 | |
Corrado Zoccolo | 573412b | 2009-12-06 11:48:52 +0100 | [diff] [blame] | 351 | unsigned long last_delayed_sync; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 352 | }; |
| 353 | |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 354 | static struct cfq_group *cfq_get_next_cfqg(struct cfq_data *cfqd); |
| 355 | |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 356 | static struct cfq_rb_root *service_tree_for(struct cfq_group *cfqg, |
| 357 | enum wl_prio_t prio, |
Vivek Goyal | 65b32a5 | 2009-12-16 17:52:59 -0500 | [diff] [blame] | 358 | enum wl_type_t type) |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 359 | { |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 360 | if (!cfqg) |
| 361 | return NULL; |
| 362 | |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 363 | if (prio == IDLE_WORKLOAD) |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 364 | return &cfqg->service_tree_idle; |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 365 | |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 366 | return &cfqg->service_trees[prio][type]; |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 367 | } |
| 368 | |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 369 | enum cfqq_state_flags { |
Jens Axboe | b0b8d749 | 2007-01-19 11:35:30 +1100 | [diff] [blame] | 370 | CFQ_CFQQ_FLAG_on_rr = 0, /* on round-robin busy list */ |
| 371 | CFQ_CFQQ_FLAG_wait_request, /* waiting for a request */ |
Jens Axboe | b029195 | 2009-04-07 11:38:31 +0200 | [diff] [blame] | 372 | CFQ_CFQQ_FLAG_must_dispatch, /* must be allowed a dispatch */ |
Jens Axboe | b0b8d749 | 2007-01-19 11:35:30 +1100 | [diff] [blame] | 373 | CFQ_CFQQ_FLAG_must_alloc_slice, /* per-slice must_alloc flag */ |
Jens Axboe | b0b8d749 | 2007-01-19 11:35:30 +1100 | [diff] [blame] | 374 | CFQ_CFQQ_FLAG_fifo_expire, /* FIFO checked in this slice */ |
| 375 | CFQ_CFQQ_FLAG_idle_window, /* slice idling enabled */ |
| 376 | CFQ_CFQQ_FLAG_prio_changed, /* task priority has changed */ |
Jens Axboe | 44f7c16 | 2007-01-19 11:51:58 +1100 | [diff] [blame] | 377 | CFQ_CFQQ_FLAG_slice_new, /* no requests dispatched in slice */ |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 378 | CFQ_CFQQ_FLAG_sync, /* synchronous queue */ |
Jeff Moyer | b3b6d04 | 2009-10-23 17:14:51 -0400 | [diff] [blame] | 379 | CFQ_CFQQ_FLAG_coop, /* cfqq is shared */ |
Shaohua Li | ae54abe | 2010-02-05 13:11:45 +0100 | [diff] [blame] | 380 | CFQ_CFQQ_FLAG_split_coop, /* shared cfqq will be splitted */ |
Corrado Zoccolo | 76280af | 2009-11-26 10:02:58 +0100 | [diff] [blame] | 381 | CFQ_CFQQ_FLAG_deep, /* sync cfqq experienced large depth */ |
Vivek Goyal | f75edf2 | 2009-12-03 12:59:53 -0500 | [diff] [blame] | 382 | CFQ_CFQQ_FLAG_wait_busy, /* Waiting for next request */ |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 383 | }; |
| 384 | |
| 385 | #define CFQ_CFQQ_FNS(name) \ |
| 386 | static inline void cfq_mark_cfqq_##name(struct cfq_queue *cfqq) \ |
| 387 | { \ |
Jens Axboe | fe094d9 | 2008-01-31 13:08:54 +0100 | [diff] [blame] | 388 | (cfqq)->flags |= (1 << CFQ_CFQQ_FLAG_##name); \ |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 389 | } \ |
| 390 | static inline void cfq_clear_cfqq_##name(struct cfq_queue *cfqq) \ |
| 391 | { \ |
Jens Axboe | fe094d9 | 2008-01-31 13:08:54 +0100 | [diff] [blame] | 392 | (cfqq)->flags &= ~(1 << CFQ_CFQQ_FLAG_##name); \ |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 393 | } \ |
| 394 | static inline int cfq_cfqq_##name(const struct cfq_queue *cfqq) \ |
| 395 | { \ |
Jens Axboe | fe094d9 | 2008-01-31 13:08:54 +0100 | [diff] [blame] | 396 | return ((cfqq)->flags & (1 << CFQ_CFQQ_FLAG_##name)) != 0; \ |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 397 | } |
| 398 | |
| 399 | CFQ_CFQQ_FNS(on_rr); |
| 400 | CFQ_CFQQ_FNS(wait_request); |
Jens Axboe | b029195 | 2009-04-07 11:38:31 +0200 | [diff] [blame] | 401 | CFQ_CFQQ_FNS(must_dispatch); |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 402 | CFQ_CFQQ_FNS(must_alloc_slice); |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 403 | CFQ_CFQQ_FNS(fifo_expire); |
| 404 | CFQ_CFQQ_FNS(idle_window); |
| 405 | CFQ_CFQQ_FNS(prio_changed); |
Jens Axboe | 44f7c16 | 2007-01-19 11:51:58 +1100 | [diff] [blame] | 406 | CFQ_CFQQ_FNS(slice_new); |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 407 | CFQ_CFQQ_FNS(sync); |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 408 | CFQ_CFQQ_FNS(coop); |
Shaohua Li | ae54abe | 2010-02-05 13:11:45 +0100 | [diff] [blame] | 409 | CFQ_CFQQ_FNS(split_coop); |
Corrado Zoccolo | 76280af | 2009-11-26 10:02:58 +0100 | [diff] [blame] | 410 | CFQ_CFQQ_FNS(deep); |
Vivek Goyal | f75edf2 | 2009-12-03 12:59:53 -0500 | [diff] [blame] | 411 | CFQ_CFQQ_FNS(wait_busy); |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 412 | #undef CFQ_CFQQ_FNS |
| 413 | |
Tejun Heo | f95a04a | 2012-04-16 13:57:26 -0700 | [diff] [blame] | 414 | static inline struct cfq_group *pd_to_cfqg(struct blkg_policy_data *pd) |
| 415 | { |
| 416 | return pd ? container_of(pd, struct cfq_group, pd) : NULL; |
| 417 | } |
| 418 | |
Tejun Heo | f95a04a | 2012-04-16 13:57:26 -0700 | [diff] [blame] | 419 | static inline struct blkcg_gq *cfqg_to_blkg(struct cfq_group *cfqg) |
| 420 | { |
| 421 | return pd_to_blkg(&cfqg->pd); |
| 422 | } |
| 423 | |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 424 | #if defined(CONFIG_CFQ_GROUP_IOSCHED) && defined(CONFIG_DEBUG_BLK_CGROUP) |
Tejun Heo | 2ce4d50 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 425 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 426 | /* cfqg stats flags */ |
| 427 | enum cfqg_stats_flags { |
| 428 | CFQG_stats_waiting = 0, |
| 429 | CFQG_stats_idling, |
| 430 | CFQG_stats_empty, |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 431 | }; |
| 432 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 433 | #define CFQG_FLAG_FNS(name) \ |
| 434 | static inline void cfqg_stats_mark_##name(struct cfqg_stats *stats) \ |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 435 | { \ |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 436 | stats->flags |= (1 << CFQG_stats_##name); \ |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 437 | } \ |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 438 | static inline void cfqg_stats_clear_##name(struct cfqg_stats *stats) \ |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 439 | { \ |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 440 | stats->flags &= ~(1 << CFQG_stats_##name); \ |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 441 | } \ |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 442 | static inline int cfqg_stats_##name(struct cfqg_stats *stats) \ |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 443 | { \ |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 444 | return (stats->flags & (1 << CFQG_stats_##name)) != 0; \ |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 445 | } \ |
| 446 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 447 | CFQG_FLAG_FNS(waiting) |
| 448 | CFQG_FLAG_FNS(idling) |
| 449 | CFQG_FLAG_FNS(empty) |
| 450 | #undef CFQG_FLAG_FNS |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 451 | |
| 452 | /* This should be called with the queue_lock held. */ |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 453 | static void cfqg_stats_update_group_wait_time(struct cfqg_stats *stats) |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 454 | { |
| 455 | unsigned long long now; |
| 456 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 457 | if (!cfqg_stats_waiting(stats)) |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 458 | return; |
| 459 | |
| 460 | now = sched_clock(); |
| 461 | if (time_after64(now, stats->start_group_wait_time)) |
| 462 | blkg_stat_add(&stats->group_wait_time, |
| 463 | now - stats->start_group_wait_time); |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 464 | cfqg_stats_clear_waiting(stats); |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 465 | } |
| 466 | |
| 467 | /* This should be called with the queue_lock held. */ |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 468 | static void cfqg_stats_set_start_group_wait_time(struct cfq_group *cfqg, |
| 469 | struct cfq_group *curr_cfqg) |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 470 | { |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 471 | struct cfqg_stats *stats = &cfqg->stats; |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 472 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 473 | if (cfqg_stats_waiting(stats)) |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 474 | return; |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 475 | if (cfqg == curr_cfqg) |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 476 | return; |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 477 | stats->start_group_wait_time = sched_clock(); |
| 478 | cfqg_stats_mark_waiting(stats); |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 479 | } |
| 480 | |
| 481 | /* This should be called with the queue_lock held. */ |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 482 | static void cfqg_stats_end_empty_time(struct cfqg_stats *stats) |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 483 | { |
| 484 | unsigned long long now; |
| 485 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 486 | if (!cfqg_stats_empty(stats)) |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 487 | return; |
| 488 | |
| 489 | now = sched_clock(); |
| 490 | if (time_after64(now, stats->start_empty_time)) |
| 491 | blkg_stat_add(&stats->empty_time, |
| 492 | now - stats->start_empty_time); |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 493 | cfqg_stats_clear_empty(stats); |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 494 | } |
| 495 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 496 | static void cfqg_stats_update_dequeue(struct cfq_group *cfqg) |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 497 | { |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 498 | blkg_stat_add(&cfqg->stats.dequeue, 1); |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 499 | } |
| 500 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 501 | static void cfqg_stats_set_start_empty_time(struct cfq_group *cfqg) |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 502 | { |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 503 | struct cfqg_stats *stats = &cfqg->stats; |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 504 | |
| 505 | if (blkg_rwstat_sum(&stats->queued)) |
| 506 | return; |
| 507 | |
| 508 | /* |
| 509 | * group is already marked empty. This can happen if cfqq got new |
| 510 | * request in parent group and moved to this group while being added |
| 511 | * to service tree. Just ignore the event and move on. |
| 512 | */ |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 513 | if (cfqg_stats_empty(stats)) |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 514 | return; |
| 515 | |
| 516 | stats->start_empty_time = sched_clock(); |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 517 | cfqg_stats_mark_empty(stats); |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 518 | } |
| 519 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 520 | static void cfqg_stats_update_idle_time(struct cfq_group *cfqg) |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 521 | { |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 522 | struct cfqg_stats *stats = &cfqg->stats; |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 523 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 524 | if (cfqg_stats_idling(stats)) { |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 525 | unsigned long long now = sched_clock(); |
| 526 | |
| 527 | if (time_after64(now, stats->start_idle_time)) |
| 528 | blkg_stat_add(&stats->idle_time, |
| 529 | now - stats->start_idle_time); |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 530 | cfqg_stats_clear_idling(stats); |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 531 | } |
| 532 | } |
| 533 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 534 | static void cfqg_stats_set_start_idle_time(struct cfq_group *cfqg) |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 535 | { |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 536 | struct cfqg_stats *stats = &cfqg->stats; |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 537 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 538 | BUG_ON(cfqg_stats_idling(stats)); |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 539 | |
| 540 | stats->start_idle_time = sched_clock(); |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 541 | cfqg_stats_mark_idling(stats); |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 542 | } |
| 543 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 544 | static void cfqg_stats_update_avg_queue_size(struct cfq_group *cfqg) |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 545 | { |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 546 | struct cfqg_stats *stats = &cfqg->stats; |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 547 | |
| 548 | blkg_stat_add(&stats->avg_queue_size_sum, |
| 549 | blkg_rwstat_sum(&stats->queued)); |
| 550 | blkg_stat_add(&stats->avg_queue_size_samples, 1); |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 551 | cfqg_stats_update_group_wait_time(stats); |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 552 | } |
| 553 | |
| 554 | #else /* CONFIG_CFQ_GROUP_IOSCHED && CONFIG_DEBUG_BLK_CGROUP */ |
| 555 | |
Tejun Heo | f48ec1d | 2012-04-13 13:11:25 -0700 | [diff] [blame] | 556 | static inline void cfqg_stats_set_start_group_wait_time(struct cfq_group *cfqg, struct cfq_group *curr_cfqg) { } |
| 557 | static inline void cfqg_stats_end_empty_time(struct cfqg_stats *stats) { } |
| 558 | static inline void cfqg_stats_update_dequeue(struct cfq_group *cfqg) { } |
| 559 | static inline void cfqg_stats_set_start_empty_time(struct cfq_group *cfqg) { } |
| 560 | static inline void cfqg_stats_update_idle_time(struct cfq_group *cfqg) { } |
| 561 | static inline void cfqg_stats_set_start_idle_time(struct cfq_group *cfqg) { } |
| 562 | static inline void cfqg_stats_update_avg_queue_size(struct cfq_group *cfqg) { } |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 563 | |
| 564 | #endif /* CONFIG_CFQ_GROUP_IOSCHED && CONFIG_DEBUG_BLK_CGROUP */ |
| 565 | |
| 566 | #ifdef CONFIG_CFQ_GROUP_IOSCHED |
Tejun Heo | 2ce4d50 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 567 | |
Tejun Heo | ffea73f | 2012-06-04 10:02:29 +0200 | [diff] [blame] | 568 | static struct blkcg_policy blkcg_policy_cfq; |
| 569 | |
| 570 | static inline struct cfq_group *blkg_to_cfqg(struct blkcg_gq *blkg) |
| 571 | { |
| 572 | return pd_to_cfqg(blkg_to_pd(blkg, &blkcg_policy_cfq)); |
| 573 | } |
| 574 | |
Tejun Heo | eb7d8c07 | 2012-03-23 14:02:53 +0100 | [diff] [blame] | 575 | static inline void cfqg_get(struct cfq_group *cfqg) |
| 576 | { |
| 577 | return blkg_get(cfqg_to_blkg(cfqg)); |
| 578 | } |
| 579 | |
| 580 | static inline void cfqg_put(struct cfq_group *cfqg) |
| 581 | { |
| 582 | return blkg_put(cfqg_to_blkg(cfqg)); |
| 583 | } |
| 584 | |
Tejun Heo | 54e7ed1 | 2012-04-16 13:57:23 -0700 | [diff] [blame] | 585 | #define cfq_log_cfqq(cfqd, cfqq, fmt, args...) do { \ |
| 586 | char __pbuf[128]; \ |
| 587 | \ |
| 588 | blkg_path(cfqg_to_blkg((cfqq)->cfqg), __pbuf, sizeof(__pbuf)); \ |
Vivek Goyal | 2868ef7 | 2009-12-03 12:59:48 -0500 | [diff] [blame] | 589 | blk_add_trace_msg((cfqd)->queue, "cfq%d%c %s " fmt, (cfqq)->pid, \ |
Tejun Heo | 54e7ed1 | 2012-04-16 13:57:23 -0700 | [diff] [blame] | 590 | cfq_cfqq_sync((cfqq)) ? 'S' : 'A', \ |
| 591 | __pbuf, ##args); \ |
| 592 | } while (0) |
Vivek Goyal | 2868ef7 | 2009-12-03 12:59:48 -0500 | [diff] [blame] | 593 | |
Tejun Heo | 54e7ed1 | 2012-04-16 13:57:23 -0700 | [diff] [blame] | 594 | #define cfq_log_cfqg(cfqd, cfqg, fmt, args...) do { \ |
| 595 | char __pbuf[128]; \ |
| 596 | \ |
| 597 | blkg_path(cfqg_to_blkg(cfqg), __pbuf, sizeof(__pbuf)); \ |
| 598 | blk_add_trace_msg((cfqd)->queue, "%s " fmt, __pbuf, ##args); \ |
| 599 | } while (0) |
Vivek Goyal | 2868ef7 | 2009-12-03 12:59:48 -0500 | [diff] [blame] | 600 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 601 | static inline void cfqg_stats_update_io_add(struct cfq_group *cfqg, |
| 602 | struct cfq_group *curr_cfqg, int rw) |
Tejun Heo | 2ce4d50 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 603 | { |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 604 | blkg_rwstat_add(&cfqg->stats.queued, rw, 1); |
| 605 | cfqg_stats_end_empty_time(&cfqg->stats); |
| 606 | cfqg_stats_set_start_group_wait_time(cfqg, curr_cfqg); |
Tejun Heo | 2ce4d50 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 607 | } |
| 608 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 609 | static inline void cfqg_stats_update_timeslice_used(struct cfq_group *cfqg, |
| 610 | unsigned long time, unsigned long unaccounted_time) |
Tejun Heo | 2ce4d50 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 611 | { |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 612 | blkg_stat_add(&cfqg->stats.time, time); |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 613 | #ifdef CONFIG_DEBUG_BLK_CGROUP |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 614 | blkg_stat_add(&cfqg->stats.unaccounted_time, unaccounted_time); |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 615 | #endif |
Tejun Heo | 2ce4d50 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 616 | } |
| 617 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 618 | static inline void cfqg_stats_update_io_remove(struct cfq_group *cfqg, int rw) |
Tejun Heo | 2ce4d50 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 619 | { |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 620 | blkg_rwstat_add(&cfqg->stats.queued, rw, -1); |
Tejun Heo | 2ce4d50 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 621 | } |
| 622 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 623 | static inline void cfqg_stats_update_io_merged(struct cfq_group *cfqg, int rw) |
Tejun Heo | 2ce4d50 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 624 | { |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 625 | blkg_rwstat_add(&cfqg->stats.merged, rw, 1); |
Tejun Heo | 2ce4d50 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 626 | } |
| 627 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 628 | static inline void cfqg_stats_update_dispatch(struct cfq_group *cfqg, |
| 629 | uint64_t bytes, int rw) |
Tejun Heo | 2ce4d50 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 630 | { |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 631 | blkg_stat_add(&cfqg->stats.sectors, bytes >> 9); |
| 632 | blkg_rwstat_add(&cfqg->stats.serviced, rw, 1); |
| 633 | blkg_rwstat_add(&cfqg->stats.service_bytes, rw, bytes); |
Tejun Heo | 2ce4d50 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 634 | } |
| 635 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 636 | static inline void cfqg_stats_update_completion(struct cfq_group *cfqg, |
| 637 | uint64_t start_time, uint64_t io_start_time, int rw) |
Tejun Heo | 2ce4d50 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 638 | { |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 639 | struct cfqg_stats *stats = &cfqg->stats; |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 640 | unsigned long long now = sched_clock(); |
Tejun Heo | 629ed0b | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 641 | |
| 642 | if (time_after64(now, io_start_time)) |
| 643 | blkg_rwstat_add(&stats->service_time, rw, now - io_start_time); |
| 644 | if (time_after64(io_start_time, start_time)) |
| 645 | blkg_rwstat_add(&stats->wait_time, rw, |
| 646 | io_start_time - start_time); |
Tejun Heo | 2ce4d50 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 647 | } |
| 648 | |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 649 | static void cfq_pd_reset_stats(struct blkcg_gq *blkg) |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 650 | { |
| 651 | struct cfq_group *cfqg = blkg_to_cfqg(blkg); |
| 652 | struct cfqg_stats *stats = &cfqg->stats; |
| 653 | |
| 654 | /* queued stats shouldn't be cleared */ |
| 655 | blkg_rwstat_reset(&stats->service_bytes); |
| 656 | blkg_rwstat_reset(&stats->serviced); |
| 657 | blkg_rwstat_reset(&stats->merged); |
| 658 | blkg_rwstat_reset(&stats->service_time); |
| 659 | blkg_rwstat_reset(&stats->wait_time); |
| 660 | blkg_stat_reset(&stats->time); |
| 661 | #ifdef CONFIG_DEBUG_BLK_CGROUP |
| 662 | blkg_stat_reset(&stats->unaccounted_time); |
| 663 | blkg_stat_reset(&stats->avg_queue_size_sum); |
| 664 | blkg_stat_reset(&stats->avg_queue_size_samples); |
| 665 | blkg_stat_reset(&stats->dequeue); |
| 666 | blkg_stat_reset(&stats->group_wait_time); |
| 667 | blkg_stat_reset(&stats->idle_time); |
| 668 | blkg_stat_reset(&stats->empty_time); |
| 669 | #endif |
| 670 | } |
| 671 | |
Tejun Heo | eb7d8c07 | 2012-03-23 14:02:53 +0100 | [diff] [blame] | 672 | #else /* CONFIG_CFQ_GROUP_IOSCHED */ |
| 673 | |
Tejun Heo | eb7d8c07 | 2012-03-23 14:02:53 +0100 | [diff] [blame] | 674 | static inline void cfqg_get(struct cfq_group *cfqg) { } |
| 675 | static inline void cfqg_put(struct cfq_group *cfqg) { } |
| 676 | |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 677 | #define cfq_log_cfqq(cfqd, cfqq, fmt, args...) \ |
| 678 | blk_add_trace_msg((cfqd)->queue, "cfq%d " fmt, (cfqq)->pid, ##args) |
Kyungmin Park | 4495a7d | 2011-05-31 10:04:09 +0200 | [diff] [blame] | 679 | #define cfq_log_cfqg(cfqd, cfqg, fmt, args...) do {} while (0) |
Tejun Heo | eb7d8c07 | 2012-03-23 14:02:53 +0100 | [diff] [blame] | 680 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 681 | static inline void cfqg_stats_update_io_add(struct cfq_group *cfqg, |
| 682 | struct cfq_group *curr_cfqg, int rw) { } |
| 683 | static inline void cfqg_stats_update_timeslice_used(struct cfq_group *cfqg, |
| 684 | unsigned long time, unsigned long unaccounted_time) { } |
| 685 | static inline void cfqg_stats_update_io_remove(struct cfq_group *cfqg, int rw) { } |
| 686 | static inline void cfqg_stats_update_io_merged(struct cfq_group *cfqg, int rw) { } |
| 687 | static inline void cfqg_stats_update_dispatch(struct cfq_group *cfqg, |
| 688 | uint64_t bytes, int rw) { } |
| 689 | static inline void cfqg_stats_update_completion(struct cfq_group *cfqg, |
| 690 | uint64_t start_time, uint64_t io_start_time, int rw) { } |
Tejun Heo | 2ce4d50 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 691 | |
Tejun Heo | eb7d8c07 | 2012-03-23 14:02:53 +0100 | [diff] [blame] | 692 | #endif /* CONFIG_CFQ_GROUP_IOSCHED */ |
| 693 | |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 694 | #define cfq_log(cfqd, fmt, args...) \ |
| 695 | blk_add_trace_msg((cfqd)->queue, "cfq " fmt, ##args) |
| 696 | |
Vivek Goyal | 615f025 | 2009-12-03 12:59:39 -0500 | [diff] [blame] | 697 | /* Traverses through cfq group service trees */ |
| 698 | #define for_each_cfqg_st(cfqg, i, j, st) \ |
| 699 | for (i = 0; i <= IDLE_WORKLOAD; i++) \ |
| 700 | for (j = 0, st = i < IDLE_WORKLOAD ? &cfqg->service_trees[i][j]\ |
| 701 | : &cfqg->service_tree_idle; \ |
| 702 | (i < IDLE_WORKLOAD && j <= SYNC_WORKLOAD) || \ |
| 703 | (i == IDLE_WORKLOAD && j == 0); \ |
| 704 | j++, st = i < IDLE_WORKLOAD ? \ |
| 705 | &cfqg->service_trees[i][j]: NULL) \ |
| 706 | |
Shaohua Li | f5f2b6c | 2011-07-12 14:24:55 +0200 | [diff] [blame] | 707 | static inline bool cfq_io_thinktime_big(struct cfq_data *cfqd, |
| 708 | struct cfq_ttime *ttime, bool group_idle) |
| 709 | { |
| 710 | unsigned long slice; |
| 711 | if (!sample_valid(ttime->ttime_samples)) |
| 712 | return false; |
| 713 | if (group_idle) |
| 714 | slice = cfqd->cfq_group_idle; |
| 715 | else |
| 716 | slice = cfqd->cfq_slice_idle; |
| 717 | return ttime->ttime_mean > slice; |
| 718 | } |
Vivek Goyal | 615f025 | 2009-12-03 12:59:39 -0500 | [diff] [blame] | 719 | |
Vivek Goyal | 02b3508 | 2010-08-23 12:23:53 +0200 | [diff] [blame] | 720 | static inline bool iops_mode(struct cfq_data *cfqd) |
| 721 | { |
| 722 | /* |
| 723 | * If we are not idling on queues and it is a NCQ drive, parallel |
| 724 | * execution of requests is on and measuring time is not possible |
| 725 | * in most of the cases until and unless we drive shallower queue |
| 726 | * depths and that becomes a performance bottleneck. In such cases |
| 727 | * switch to start providing fairness in terms of number of IOs. |
| 728 | */ |
| 729 | if (!cfqd->cfq_slice_idle && cfqd->hw_tag) |
| 730 | return true; |
| 731 | else |
| 732 | return false; |
| 733 | } |
| 734 | |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 735 | static inline enum wl_prio_t cfqq_prio(struct cfq_queue *cfqq) |
| 736 | { |
| 737 | if (cfq_class_idle(cfqq)) |
| 738 | return IDLE_WORKLOAD; |
| 739 | if (cfq_class_rt(cfqq)) |
| 740 | return RT_WORKLOAD; |
| 741 | return BE_WORKLOAD; |
| 742 | } |
| 743 | |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 744 | |
| 745 | static enum wl_type_t cfqq_type(struct cfq_queue *cfqq) |
| 746 | { |
| 747 | if (!cfq_cfqq_sync(cfqq)) |
| 748 | return ASYNC_WORKLOAD; |
| 749 | if (!cfq_cfqq_idle_window(cfqq)) |
| 750 | return SYNC_NOIDLE_WORKLOAD; |
| 751 | return SYNC_WORKLOAD; |
| 752 | } |
| 753 | |
Vivek Goyal | 58ff82f | 2009-12-03 12:59:44 -0500 | [diff] [blame] | 754 | static inline int cfq_group_busy_queues_wl(enum wl_prio_t wl, |
| 755 | struct cfq_data *cfqd, |
| 756 | struct cfq_group *cfqg) |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 757 | { |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 758 | if (wl == IDLE_WORKLOAD) |
| 759 | return cfqg->service_tree_idle.count; |
| 760 | |
| 761 | return cfqg->service_trees[wl][ASYNC_WORKLOAD].count |
| 762 | + cfqg->service_trees[wl][SYNC_NOIDLE_WORKLOAD].count |
| 763 | + cfqg->service_trees[wl][SYNC_WORKLOAD].count; |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 764 | } |
| 765 | |
Vivek Goyal | f26bd1f | 2009-12-03 12:59:54 -0500 | [diff] [blame] | 766 | static inline int cfqg_busy_async_queues(struct cfq_data *cfqd, |
| 767 | struct cfq_group *cfqg) |
| 768 | { |
| 769 | return cfqg->service_trees[RT_WORKLOAD][ASYNC_WORKLOAD].count |
| 770 | + cfqg->service_trees[BE_WORKLOAD][ASYNC_WORKLOAD].count; |
| 771 | } |
| 772 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 773 | static void cfq_dispatch_insert(struct request_queue *, struct request *); |
Tejun Heo | 4f85cb9 | 2012-03-05 13:15:28 -0800 | [diff] [blame] | 774 | static struct cfq_queue *cfq_get_queue(struct cfq_data *cfqd, bool is_sync, |
Tejun Heo | abede6d | 2012-03-19 15:10:57 -0700 | [diff] [blame] | 775 | struct cfq_io_cq *cic, struct bio *bio, |
Tejun Heo | 4f85cb9 | 2012-03-05 13:15:28 -0800 | [diff] [blame] | 776 | gfp_t gfp_mask); |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 777 | |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 778 | static inline struct cfq_io_cq *icq_to_cic(struct io_cq *icq) |
| 779 | { |
| 780 | /* cic->icq is the first member, %NULL will convert to %NULL */ |
| 781 | return container_of(icq, struct cfq_io_cq, icq); |
| 782 | } |
| 783 | |
Tejun Heo | 47fdd4c | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 784 | static inline struct cfq_io_cq *cfq_cic_lookup(struct cfq_data *cfqd, |
| 785 | struct io_context *ioc) |
| 786 | { |
| 787 | if (ioc) |
| 788 | return icq_to_cic(ioc_lookup_icq(ioc, cfqd->queue)); |
| 789 | return NULL; |
| 790 | } |
| 791 | |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 792 | static inline struct cfq_queue *cic_to_cfqq(struct cfq_io_cq *cic, bool is_sync) |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 793 | { |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 794 | return cic->cfqq[is_sync]; |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 795 | } |
| 796 | |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 797 | static inline void cic_set_cfqq(struct cfq_io_cq *cic, struct cfq_queue *cfqq, |
| 798 | bool is_sync) |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 799 | { |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 800 | cic->cfqq[is_sync] = cfqq; |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 801 | } |
| 802 | |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 803 | static inline struct cfq_data *cic_to_cfqd(struct cfq_io_cq *cic) |
Konstantin Khlebnikov | bca4b91 | 2010-05-20 23:21:34 +0400 | [diff] [blame] | 804 | { |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 805 | return cic->icq.q->elevator->elevator_data; |
Konstantin Khlebnikov | bca4b91 | 2010-05-20 23:21:34 +0400 | [diff] [blame] | 806 | } |
| 807 | |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 808 | /* |
| 809 | * We regard a request as SYNC, if it's either a read or has the SYNC bit |
| 810 | * set (in which case it could also be direct WRITE). |
| 811 | */ |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 812 | static inline bool cfq_bio_sync(struct bio *bio) |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 813 | { |
Christoph Hellwig | 7b6d91d | 2010-08-07 18:20:39 +0200 | [diff] [blame] | 814 | return bio_data_dir(bio) == READ || (bio->bi_rw & REQ_SYNC); |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 815 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 816 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 817 | /* |
Andrew Morton | 99f95e5 | 2005-06-27 20:14:05 -0700 | [diff] [blame] | 818 | * scheduler run of queue, if there are requests pending and no one in the |
| 819 | * driver that will restart queueing |
| 820 | */ |
Jens Axboe | 23e018a | 2009-10-05 08:52:35 +0200 | [diff] [blame] | 821 | static inline void cfq_schedule_dispatch(struct cfq_data *cfqd) |
Andrew Morton | 99f95e5 | 2005-06-27 20:14:05 -0700 | [diff] [blame] | 822 | { |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 823 | if (cfqd->busy_queues) { |
| 824 | cfq_log(cfqd, "schedule dispatch"); |
Jens Axboe | 23e018a | 2009-10-05 08:52:35 +0200 | [diff] [blame] | 825 | kblockd_schedule_work(cfqd->queue, &cfqd->unplug_work); |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 826 | } |
Andrew Morton | 99f95e5 | 2005-06-27 20:14:05 -0700 | [diff] [blame] | 827 | } |
| 828 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 829 | /* |
Jens Axboe | 44f7c16 | 2007-01-19 11:51:58 +1100 | [diff] [blame] | 830 | * Scale schedule slice based on io priority. Use the sync time slice only |
| 831 | * if a queue is marked sync and has sync io queued. A sync queue with async |
| 832 | * io only, should not get full sync slice length. |
| 833 | */ |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 834 | static inline int cfq_prio_slice(struct cfq_data *cfqd, bool sync, |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 835 | unsigned short prio) |
| 836 | { |
| 837 | const int base_slice = cfqd->cfq_slice[sync]; |
| 838 | |
| 839 | WARN_ON(prio >= IOPRIO_BE_NR); |
| 840 | |
| 841 | return base_slice + (base_slice/CFQ_SLICE_SCALE * (4 - prio)); |
| 842 | } |
| 843 | |
Jens Axboe | 44f7c16 | 2007-01-19 11:51:58 +1100 | [diff] [blame] | 844 | static inline int |
| 845 | cfq_prio_to_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
| 846 | { |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 847 | return cfq_prio_slice(cfqd, cfq_cfqq_sync(cfqq), cfqq->ioprio); |
Jens Axboe | 44f7c16 | 2007-01-19 11:51:58 +1100 | [diff] [blame] | 848 | } |
| 849 | |
Vivek Goyal | 25bc6b0 | 2009-12-03 12:59:43 -0500 | [diff] [blame] | 850 | static inline u64 cfq_scale_slice(unsigned long delta, struct cfq_group *cfqg) |
| 851 | { |
| 852 | u64 d = delta << CFQ_SERVICE_SHIFT; |
| 853 | |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 854 | d = d * CFQ_WEIGHT_DEFAULT; |
Vivek Goyal | 25bc6b0 | 2009-12-03 12:59:43 -0500 | [diff] [blame] | 855 | do_div(d, cfqg->weight); |
| 856 | return d; |
| 857 | } |
| 858 | |
| 859 | static inline u64 max_vdisktime(u64 min_vdisktime, u64 vdisktime) |
| 860 | { |
| 861 | s64 delta = (s64)(vdisktime - min_vdisktime); |
| 862 | if (delta > 0) |
| 863 | min_vdisktime = vdisktime; |
| 864 | |
| 865 | return min_vdisktime; |
| 866 | } |
| 867 | |
| 868 | static inline u64 min_vdisktime(u64 min_vdisktime, u64 vdisktime) |
| 869 | { |
| 870 | s64 delta = (s64)(vdisktime - min_vdisktime); |
| 871 | if (delta < 0) |
| 872 | min_vdisktime = vdisktime; |
| 873 | |
| 874 | return min_vdisktime; |
| 875 | } |
| 876 | |
| 877 | static void update_min_vdisktime(struct cfq_rb_root *st) |
| 878 | { |
Vivek Goyal | 25bc6b0 | 2009-12-03 12:59:43 -0500 | [diff] [blame] | 879 | struct cfq_group *cfqg; |
| 880 | |
Vivek Goyal | 25bc6b0 | 2009-12-03 12:59:43 -0500 | [diff] [blame] | 881 | if (st->left) { |
| 882 | cfqg = rb_entry_cfqg(st->left); |
Gui Jianfeng | a603271 | 2011-03-07 09:28:09 +0100 | [diff] [blame] | 883 | st->min_vdisktime = max_vdisktime(st->min_vdisktime, |
| 884 | cfqg->vdisktime); |
Vivek Goyal | 25bc6b0 | 2009-12-03 12:59:43 -0500 | [diff] [blame] | 885 | } |
Vivek Goyal | 25bc6b0 | 2009-12-03 12:59:43 -0500 | [diff] [blame] | 886 | } |
| 887 | |
Corrado Zoccolo | 5db5d64 | 2009-10-26 22:44:04 +0100 | [diff] [blame] | 888 | /* |
| 889 | * get averaged number of queues of RT/BE priority. |
| 890 | * average is updated, with a formula that gives more weight to higher numbers, |
| 891 | * to quickly follows sudden increases and decrease slowly |
| 892 | */ |
| 893 | |
Vivek Goyal | 58ff82f | 2009-12-03 12:59:44 -0500 | [diff] [blame] | 894 | static inline unsigned cfq_group_get_avg_queues(struct cfq_data *cfqd, |
| 895 | struct cfq_group *cfqg, bool rt) |
Jens Axboe | 5869619c | 2009-10-28 09:27:07 +0100 | [diff] [blame] | 896 | { |
Corrado Zoccolo | 5db5d64 | 2009-10-26 22:44:04 +0100 | [diff] [blame] | 897 | unsigned min_q, max_q; |
| 898 | unsigned mult = cfq_hist_divisor - 1; |
| 899 | unsigned round = cfq_hist_divisor / 2; |
Vivek Goyal | 58ff82f | 2009-12-03 12:59:44 -0500 | [diff] [blame] | 900 | unsigned busy = cfq_group_busy_queues_wl(rt, cfqd, cfqg); |
Corrado Zoccolo | 5db5d64 | 2009-10-26 22:44:04 +0100 | [diff] [blame] | 901 | |
Vivek Goyal | 58ff82f | 2009-12-03 12:59:44 -0500 | [diff] [blame] | 902 | min_q = min(cfqg->busy_queues_avg[rt], busy); |
| 903 | max_q = max(cfqg->busy_queues_avg[rt], busy); |
| 904 | cfqg->busy_queues_avg[rt] = (mult * max_q + min_q + round) / |
Corrado Zoccolo | 5db5d64 | 2009-10-26 22:44:04 +0100 | [diff] [blame] | 905 | cfq_hist_divisor; |
Vivek Goyal | 58ff82f | 2009-12-03 12:59:44 -0500 | [diff] [blame] | 906 | return cfqg->busy_queues_avg[rt]; |
| 907 | } |
| 908 | |
| 909 | static inline unsigned |
| 910 | cfq_group_slice(struct cfq_data *cfqd, struct cfq_group *cfqg) |
| 911 | { |
| 912 | struct cfq_rb_root *st = &cfqd->grp_service_tree; |
| 913 | |
Tao Ma | 5bf14c0 | 2012-04-01 14:33:39 -0700 | [diff] [blame] | 914 | return cfqd->cfq_target_latency * cfqg->weight / st->total_weight; |
Corrado Zoccolo | 5db5d64 | 2009-10-26 22:44:04 +0100 | [diff] [blame] | 915 | } |
| 916 | |
Shaohua Li | c553f8e | 2011-01-14 08:41:03 +0100 | [diff] [blame] | 917 | static inline unsigned |
Vivek Goyal | ba5bd52 | 2011-01-19 08:25:02 -0700 | [diff] [blame] | 918 | cfq_scaled_cfqq_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
Jens Axboe | 44f7c16 | 2007-01-19 11:51:58 +1100 | [diff] [blame] | 919 | { |
Corrado Zoccolo | 5db5d64 | 2009-10-26 22:44:04 +0100 | [diff] [blame] | 920 | unsigned slice = cfq_prio_to_slice(cfqd, cfqq); |
| 921 | if (cfqd->cfq_latency) { |
Vivek Goyal | 58ff82f | 2009-12-03 12:59:44 -0500 | [diff] [blame] | 922 | /* |
| 923 | * interested queues (we consider only the ones with the same |
| 924 | * priority class in the cfq group) |
| 925 | */ |
| 926 | unsigned iq = cfq_group_get_avg_queues(cfqd, cfqq->cfqg, |
| 927 | cfq_class_rt(cfqq)); |
Corrado Zoccolo | 5db5d64 | 2009-10-26 22:44:04 +0100 | [diff] [blame] | 928 | unsigned sync_slice = cfqd->cfq_slice[1]; |
| 929 | unsigned expect_latency = sync_slice * iq; |
Vivek Goyal | 58ff82f | 2009-12-03 12:59:44 -0500 | [diff] [blame] | 930 | unsigned group_slice = cfq_group_slice(cfqd, cfqq->cfqg); |
| 931 | |
| 932 | if (expect_latency > group_slice) { |
Corrado Zoccolo | 5db5d64 | 2009-10-26 22:44:04 +0100 | [diff] [blame] | 933 | unsigned base_low_slice = 2 * cfqd->cfq_slice_idle; |
| 934 | /* scale low_slice according to IO priority |
| 935 | * and sync vs async */ |
| 936 | unsigned low_slice = |
| 937 | min(slice, base_low_slice * slice / sync_slice); |
| 938 | /* the adapted slice value is scaled to fit all iqs |
| 939 | * into the target latency */ |
Vivek Goyal | 58ff82f | 2009-12-03 12:59:44 -0500 | [diff] [blame] | 940 | slice = max(slice * group_slice / expect_latency, |
Corrado Zoccolo | 5db5d64 | 2009-10-26 22:44:04 +0100 | [diff] [blame] | 941 | low_slice); |
| 942 | } |
| 943 | } |
Shaohua Li | c553f8e | 2011-01-14 08:41:03 +0100 | [diff] [blame] | 944 | return slice; |
| 945 | } |
| 946 | |
| 947 | static inline void |
| 948 | cfq_set_prio_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
| 949 | { |
Vivek Goyal | ba5bd52 | 2011-01-19 08:25:02 -0700 | [diff] [blame] | 950 | unsigned slice = cfq_scaled_cfqq_slice(cfqd, cfqq); |
Shaohua Li | c553f8e | 2011-01-14 08:41:03 +0100 | [diff] [blame] | 951 | |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 952 | cfqq->slice_start = jiffies; |
Corrado Zoccolo | 5db5d64 | 2009-10-26 22:44:04 +0100 | [diff] [blame] | 953 | cfqq->slice_end = jiffies + slice; |
Vivek Goyal | f75edf2 | 2009-12-03 12:59:53 -0500 | [diff] [blame] | 954 | cfqq->allocated_slice = slice; |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 955 | cfq_log_cfqq(cfqd, cfqq, "set_slice=%lu", cfqq->slice_end - jiffies); |
Jens Axboe | 44f7c16 | 2007-01-19 11:51:58 +1100 | [diff] [blame] | 956 | } |
| 957 | |
| 958 | /* |
| 959 | * We need to wrap this check in cfq_cfqq_slice_new(), since ->slice_end |
| 960 | * isn't valid until the first request from the dispatch is activated |
| 961 | * and the slice time set. |
| 962 | */ |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 963 | static inline bool cfq_slice_used(struct cfq_queue *cfqq) |
Jens Axboe | 44f7c16 | 2007-01-19 11:51:58 +1100 | [diff] [blame] | 964 | { |
| 965 | if (cfq_cfqq_slice_new(cfqq)) |
Shaohua Li | c1e4475 | 2010-11-08 15:01:02 +0100 | [diff] [blame] | 966 | return false; |
Jens Axboe | 44f7c16 | 2007-01-19 11:51:58 +1100 | [diff] [blame] | 967 | if (time_before(jiffies, cfqq->slice_end)) |
Shaohua Li | c1e4475 | 2010-11-08 15:01:02 +0100 | [diff] [blame] | 968 | return false; |
Jens Axboe | 44f7c16 | 2007-01-19 11:51:58 +1100 | [diff] [blame] | 969 | |
Shaohua Li | c1e4475 | 2010-11-08 15:01:02 +0100 | [diff] [blame] | 970 | return true; |
Jens Axboe | 44f7c16 | 2007-01-19 11:51:58 +1100 | [diff] [blame] | 971 | } |
| 972 | |
| 973 | /* |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 974 | * Lifted from AS - choose which of rq1 and rq2 that is best served now. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 975 | * We choose the request that is closest to the head right now. Distance |
Andreas Mohr | e8a9905 | 2006-03-28 08:59:49 +0200 | [diff] [blame] | 976 | * behind the head is penalized and only allowed to a certain extent. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 977 | */ |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 978 | static struct request * |
Corrado Zoccolo | cf7c25c | 2009-11-08 17:16:46 +0100 | [diff] [blame] | 979 | cfq_choose_req(struct cfq_data *cfqd, struct request *rq1, struct request *rq2, sector_t last) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 980 | { |
Corrado Zoccolo | cf7c25c | 2009-11-08 17:16:46 +0100 | [diff] [blame] | 981 | sector_t s1, s2, d1 = 0, d2 = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 982 | unsigned long back_max; |
Andreas Mohr | e8a9905 | 2006-03-28 08:59:49 +0200 | [diff] [blame] | 983 | #define CFQ_RQ1_WRAP 0x01 /* request 1 wraps */ |
| 984 | #define CFQ_RQ2_WRAP 0x02 /* request 2 wraps */ |
| 985 | unsigned wrap = 0; /* bit mask: requests behind the disk head? */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 986 | |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 987 | if (rq1 == NULL || rq1 == rq2) |
| 988 | return rq2; |
| 989 | if (rq2 == NULL) |
| 990 | return rq1; |
Jens Axboe | 9c2c38a | 2005-08-24 14:57:54 +0200 | [diff] [blame] | 991 | |
Namhyung Kim | 229836b | 2011-05-24 10:23:21 +0200 | [diff] [blame] | 992 | if (rq_is_sync(rq1) != rq_is_sync(rq2)) |
| 993 | return rq_is_sync(rq1) ? rq1 : rq2; |
| 994 | |
Christoph Hellwig | 65299a3 | 2011-08-23 14:50:29 +0200 | [diff] [blame] | 995 | if ((rq1->cmd_flags ^ rq2->cmd_flags) & REQ_PRIO) |
| 996 | return rq1->cmd_flags & REQ_PRIO ? rq1 : rq2; |
Jens Axboe | b53d1ed | 2011-08-19 08:34:48 +0200 | [diff] [blame] | 997 | |
Tejun Heo | 83096eb | 2009-05-07 22:24:39 +0900 | [diff] [blame] | 998 | s1 = blk_rq_pos(rq1); |
| 999 | s2 = blk_rq_pos(rq2); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1000 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1001 | /* |
| 1002 | * by definition, 1KiB is 2 sectors |
| 1003 | */ |
| 1004 | back_max = cfqd->cfq_back_max * 2; |
| 1005 | |
| 1006 | /* |
| 1007 | * Strict one way elevator _except_ in the case where we allow |
| 1008 | * short backward seeks which are biased as twice the cost of a |
| 1009 | * similar forward seek. |
| 1010 | */ |
| 1011 | if (s1 >= last) |
| 1012 | d1 = s1 - last; |
| 1013 | else if (s1 + back_max >= last) |
| 1014 | d1 = (last - s1) * cfqd->cfq_back_penalty; |
| 1015 | else |
Andreas Mohr | e8a9905 | 2006-03-28 08:59:49 +0200 | [diff] [blame] | 1016 | wrap |= CFQ_RQ1_WRAP; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1017 | |
| 1018 | if (s2 >= last) |
| 1019 | d2 = s2 - last; |
| 1020 | else if (s2 + back_max >= last) |
| 1021 | d2 = (last - s2) * cfqd->cfq_back_penalty; |
| 1022 | else |
Andreas Mohr | e8a9905 | 2006-03-28 08:59:49 +0200 | [diff] [blame] | 1023 | wrap |= CFQ_RQ2_WRAP; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1024 | |
| 1025 | /* Found required data */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1026 | |
Andreas Mohr | e8a9905 | 2006-03-28 08:59:49 +0200 | [diff] [blame] | 1027 | /* |
| 1028 | * By doing switch() on the bit mask "wrap" we avoid having to |
| 1029 | * check two variables for all permutations: --> faster! |
| 1030 | */ |
| 1031 | switch (wrap) { |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1032 | case 0: /* common case for CFQ: rq1 and rq2 not wrapped */ |
Andreas Mohr | e8a9905 | 2006-03-28 08:59:49 +0200 | [diff] [blame] | 1033 | if (d1 < d2) |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1034 | return rq1; |
Andreas Mohr | e8a9905 | 2006-03-28 08:59:49 +0200 | [diff] [blame] | 1035 | else if (d2 < d1) |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1036 | return rq2; |
Andreas Mohr | e8a9905 | 2006-03-28 08:59:49 +0200 | [diff] [blame] | 1037 | else { |
| 1038 | if (s1 >= s2) |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1039 | return rq1; |
Andreas Mohr | e8a9905 | 2006-03-28 08:59:49 +0200 | [diff] [blame] | 1040 | else |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1041 | return rq2; |
Andreas Mohr | e8a9905 | 2006-03-28 08:59:49 +0200 | [diff] [blame] | 1042 | } |
| 1043 | |
| 1044 | case CFQ_RQ2_WRAP: |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1045 | return rq1; |
Andreas Mohr | e8a9905 | 2006-03-28 08:59:49 +0200 | [diff] [blame] | 1046 | case CFQ_RQ1_WRAP: |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1047 | return rq2; |
| 1048 | case (CFQ_RQ1_WRAP|CFQ_RQ2_WRAP): /* both rqs wrapped */ |
Andreas Mohr | e8a9905 | 2006-03-28 08:59:49 +0200 | [diff] [blame] | 1049 | default: |
| 1050 | /* |
| 1051 | * Since both rqs are wrapped, |
| 1052 | * start with the one that's further behind head |
| 1053 | * (--> only *one* back seek required), |
| 1054 | * since back seek takes more time than forward. |
| 1055 | */ |
| 1056 | if (s1 <= s2) |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1057 | return rq1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1058 | else |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1059 | return rq2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1060 | } |
| 1061 | } |
| 1062 | |
Jens Axboe | 498d3aa2 | 2007-04-26 12:54:48 +0200 | [diff] [blame] | 1063 | /* |
| 1064 | * The below is leftmost cache rbtree addon |
| 1065 | */ |
Jens Axboe | 0871714 | 2008-01-28 11:38:15 +0100 | [diff] [blame] | 1066 | static struct cfq_queue *cfq_rb_first(struct cfq_rb_root *root) |
Jens Axboe | cc09e29 | 2007-04-26 12:53:50 +0200 | [diff] [blame] | 1067 | { |
Vivek Goyal | 615f025 | 2009-12-03 12:59:39 -0500 | [diff] [blame] | 1068 | /* Service tree is empty */ |
| 1069 | if (!root->count) |
| 1070 | return NULL; |
| 1071 | |
Jens Axboe | cc09e29 | 2007-04-26 12:53:50 +0200 | [diff] [blame] | 1072 | if (!root->left) |
| 1073 | root->left = rb_first(&root->rb); |
| 1074 | |
Jens Axboe | 0871714 | 2008-01-28 11:38:15 +0100 | [diff] [blame] | 1075 | if (root->left) |
| 1076 | return rb_entry(root->left, struct cfq_queue, rb_node); |
| 1077 | |
| 1078 | return NULL; |
Jens Axboe | cc09e29 | 2007-04-26 12:53:50 +0200 | [diff] [blame] | 1079 | } |
| 1080 | |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 1081 | static struct cfq_group *cfq_rb_first_group(struct cfq_rb_root *root) |
| 1082 | { |
| 1083 | if (!root->left) |
| 1084 | root->left = rb_first(&root->rb); |
| 1085 | |
| 1086 | if (root->left) |
| 1087 | return rb_entry_cfqg(root->left); |
| 1088 | |
| 1089 | return NULL; |
| 1090 | } |
| 1091 | |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1092 | static void rb_erase_init(struct rb_node *n, struct rb_root *root) |
| 1093 | { |
| 1094 | rb_erase(n, root); |
| 1095 | RB_CLEAR_NODE(n); |
| 1096 | } |
| 1097 | |
Jens Axboe | cc09e29 | 2007-04-26 12:53:50 +0200 | [diff] [blame] | 1098 | static void cfq_rb_erase(struct rb_node *n, struct cfq_rb_root *root) |
| 1099 | { |
| 1100 | if (root->left == n) |
| 1101 | root->left = NULL; |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1102 | rb_erase_init(n, &root->rb); |
Corrado Zoccolo | aa6f6a3 | 2009-10-26 22:44:33 +0100 | [diff] [blame] | 1103 | --root->count; |
Jens Axboe | cc09e29 | 2007-04-26 12:53:50 +0200 | [diff] [blame] | 1104 | } |
| 1105 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1106 | /* |
| 1107 | * would be nice to take fifo expire time into account as well |
| 1108 | */ |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1109 | static struct request * |
| 1110 | cfq_find_next_rq(struct cfq_data *cfqd, struct cfq_queue *cfqq, |
| 1111 | struct request *last) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1112 | { |
Jens Axboe | 21183b0 | 2006-07-13 12:33:14 +0200 | [diff] [blame] | 1113 | struct rb_node *rbnext = rb_next(&last->rb_node); |
| 1114 | struct rb_node *rbprev = rb_prev(&last->rb_node); |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1115 | struct request *next = NULL, *prev = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1116 | |
Jens Axboe | 21183b0 | 2006-07-13 12:33:14 +0200 | [diff] [blame] | 1117 | BUG_ON(RB_EMPTY_NODE(&last->rb_node)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1118 | |
| 1119 | if (rbprev) |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1120 | prev = rb_entry_rq(rbprev); |
Jens Axboe | 21183b0 | 2006-07-13 12:33:14 +0200 | [diff] [blame] | 1121 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1122 | if (rbnext) |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1123 | next = rb_entry_rq(rbnext); |
Jens Axboe | 21183b0 | 2006-07-13 12:33:14 +0200 | [diff] [blame] | 1124 | else { |
| 1125 | rbnext = rb_first(&cfqq->sort_list); |
| 1126 | if (rbnext && rbnext != &last->rb_node) |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1127 | next = rb_entry_rq(rbnext); |
Jens Axboe | 21183b0 | 2006-07-13 12:33:14 +0200 | [diff] [blame] | 1128 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1129 | |
Corrado Zoccolo | cf7c25c | 2009-11-08 17:16:46 +0100 | [diff] [blame] | 1130 | return cfq_choose_req(cfqd, next, prev, blk_rq_pos(last)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1131 | } |
| 1132 | |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 1133 | static unsigned long cfq_slice_offset(struct cfq_data *cfqd, |
| 1134 | struct cfq_queue *cfqq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1135 | { |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 1136 | /* |
| 1137 | * just an approximation, should be ok. |
| 1138 | */ |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 1139 | return (cfqq->cfqg->nr_cfqq - 1) * (cfq_prio_slice(cfqd, 1, 0) - |
Jens Axboe | 464191c | 2009-11-30 09:38:13 +0100 | [diff] [blame] | 1140 | cfq_prio_slice(cfqd, cfq_cfqq_sync(cfqq), cfqq->ioprio)); |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 1141 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1142 | |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 1143 | static inline s64 |
| 1144 | cfqg_key(struct cfq_rb_root *st, struct cfq_group *cfqg) |
| 1145 | { |
| 1146 | return cfqg->vdisktime - st->min_vdisktime; |
| 1147 | } |
| 1148 | |
| 1149 | static void |
| 1150 | __cfq_group_service_tree_add(struct cfq_rb_root *st, struct cfq_group *cfqg) |
| 1151 | { |
| 1152 | struct rb_node **node = &st->rb.rb_node; |
| 1153 | struct rb_node *parent = NULL; |
| 1154 | struct cfq_group *__cfqg; |
| 1155 | s64 key = cfqg_key(st, cfqg); |
| 1156 | int left = 1; |
| 1157 | |
| 1158 | while (*node != NULL) { |
| 1159 | parent = *node; |
| 1160 | __cfqg = rb_entry_cfqg(parent); |
| 1161 | |
| 1162 | if (key < cfqg_key(st, __cfqg)) |
| 1163 | node = &parent->rb_left; |
| 1164 | else { |
| 1165 | node = &parent->rb_right; |
| 1166 | left = 0; |
| 1167 | } |
| 1168 | } |
| 1169 | |
| 1170 | if (left) |
| 1171 | st->left = &cfqg->rb_node; |
| 1172 | |
| 1173 | rb_link_node(&cfqg->rb_node, parent, node); |
| 1174 | rb_insert_color(&cfqg->rb_node, &st->rb); |
| 1175 | } |
| 1176 | |
| 1177 | static void |
Justin TerAvest | 8184f93 | 2011-03-17 16:12:36 +0100 | [diff] [blame] | 1178 | cfq_update_group_weight(struct cfq_group *cfqg) |
| 1179 | { |
| 1180 | BUG_ON(!RB_EMPTY_NODE(&cfqg->rb_node)); |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1181 | if (cfqg->new_weight) { |
Justin TerAvest | 8184f93 | 2011-03-17 16:12:36 +0100 | [diff] [blame] | 1182 | cfqg->weight = cfqg->new_weight; |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1183 | cfqg->new_weight = 0; |
Justin TerAvest | 8184f93 | 2011-03-17 16:12:36 +0100 | [diff] [blame] | 1184 | } |
| 1185 | } |
| 1186 | |
| 1187 | static void |
| 1188 | cfq_group_service_tree_add(struct cfq_rb_root *st, struct cfq_group *cfqg) |
| 1189 | { |
| 1190 | BUG_ON(!RB_EMPTY_NODE(&cfqg->rb_node)); |
| 1191 | |
| 1192 | cfq_update_group_weight(cfqg); |
| 1193 | __cfq_group_service_tree_add(st, cfqg); |
| 1194 | st->total_weight += cfqg->weight; |
| 1195 | } |
| 1196 | |
| 1197 | static void |
| 1198 | cfq_group_notify_queue_add(struct cfq_data *cfqd, struct cfq_group *cfqg) |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 1199 | { |
| 1200 | struct cfq_rb_root *st = &cfqd->grp_service_tree; |
| 1201 | struct cfq_group *__cfqg; |
| 1202 | struct rb_node *n; |
| 1203 | |
| 1204 | cfqg->nr_cfqq++; |
Gui Jianfeng | 760701b | 2010-11-30 20:52:47 +0100 | [diff] [blame] | 1205 | if (!RB_EMPTY_NODE(&cfqg->rb_node)) |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 1206 | return; |
| 1207 | |
| 1208 | /* |
| 1209 | * Currently put the group at the end. Later implement something |
| 1210 | * so that groups get lesser vtime based on their weights, so that |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 1211 | * if group does not loose all if it was not continuously backlogged. |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 1212 | */ |
| 1213 | n = rb_last(&st->rb); |
| 1214 | if (n) { |
| 1215 | __cfqg = rb_entry_cfqg(n); |
| 1216 | cfqg->vdisktime = __cfqg->vdisktime + CFQ_IDLE_DELAY; |
| 1217 | } else |
| 1218 | cfqg->vdisktime = st->min_vdisktime; |
Justin TerAvest | 8184f93 | 2011-03-17 16:12:36 +0100 | [diff] [blame] | 1219 | cfq_group_service_tree_add(st, cfqg); |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 1220 | } |
| 1221 | |
| 1222 | static void |
Justin TerAvest | 8184f93 | 2011-03-17 16:12:36 +0100 | [diff] [blame] | 1223 | cfq_group_service_tree_del(struct cfq_rb_root *st, struct cfq_group *cfqg) |
| 1224 | { |
| 1225 | st->total_weight -= cfqg->weight; |
| 1226 | if (!RB_EMPTY_NODE(&cfqg->rb_node)) |
| 1227 | cfq_rb_erase(&cfqg->rb_node, st); |
| 1228 | } |
| 1229 | |
| 1230 | static void |
| 1231 | cfq_group_notify_queue_del(struct cfq_data *cfqd, struct cfq_group *cfqg) |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 1232 | { |
| 1233 | struct cfq_rb_root *st = &cfqd->grp_service_tree; |
| 1234 | |
| 1235 | BUG_ON(cfqg->nr_cfqq < 1); |
| 1236 | cfqg->nr_cfqq--; |
Vivek Goyal | 25bc6b0 | 2009-12-03 12:59:43 -0500 | [diff] [blame] | 1237 | |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 1238 | /* If there are other cfq queues under this group, don't delete it */ |
| 1239 | if (cfqg->nr_cfqq) |
| 1240 | return; |
| 1241 | |
Vivek Goyal | 2868ef7 | 2009-12-03 12:59:48 -0500 | [diff] [blame] | 1242 | cfq_log_cfqg(cfqd, cfqg, "del_from_rr group"); |
Justin TerAvest | 8184f93 | 2011-03-17 16:12:36 +0100 | [diff] [blame] | 1243 | cfq_group_service_tree_del(st, cfqg); |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 1244 | cfqg->saved_workload_slice = 0; |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1245 | cfqg_stats_update_dequeue(cfqg); |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 1246 | } |
| 1247 | |
Justin TerAvest | 167400d | 2011-03-12 16:54:00 +0100 | [diff] [blame] | 1248 | static inline unsigned int cfq_cfqq_slice_usage(struct cfq_queue *cfqq, |
| 1249 | unsigned int *unaccounted_time) |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 1250 | { |
Vivek Goyal | f75edf2 | 2009-12-03 12:59:53 -0500 | [diff] [blame] | 1251 | unsigned int slice_used; |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 1252 | |
| 1253 | /* |
| 1254 | * Queue got expired before even a single request completed or |
| 1255 | * got expired immediately after first request completion. |
| 1256 | */ |
| 1257 | if (!cfqq->slice_start || cfqq->slice_start == jiffies) { |
| 1258 | /* |
| 1259 | * Also charge the seek time incurred to the group, otherwise |
| 1260 | * if there are mutiple queues in the group, each can dispatch |
| 1261 | * a single request on seeky media and cause lots of seek time |
| 1262 | * and group will never know it. |
| 1263 | */ |
| 1264 | slice_used = max_t(unsigned, (jiffies - cfqq->dispatch_start), |
| 1265 | 1); |
| 1266 | } else { |
| 1267 | slice_used = jiffies - cfqq->slice_start; |
Justin TerAvest | 167400d | 2011-03-12 16:54:00 +0100 | [diff] [blame] | 1268 | if (slice_used > cfqq->allocated_slice) { |
| 1269 | *unaccounted_time = slice_used - cfqq->allocated_slice; |
Vivek Goyal | f75edf2 | 2009-12-03 12:59:53 -0500 | [diff] [blame] | 1270 | slice_used = cfqq->allocated_slice; |
Justin TerAvest | 167400d | 2011-03-12 16:54:00 +0100 | [diff] [blame] | 1271 | } |
| 1272 | if (time_after(cfqq->slice_start, cfqq->dispatch_start)) |
| 1273 | *unaccounted_time += cfqq->slice_start - |
| 1274 | cfqq->dispatch_start; |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 1275 | } |
| 1276 | |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 1277 | return slice_used; |
| 1278 | } |
| 1279 | |
| 1280 | static void cfq_group_served(struct cfq_data *cfqd, struct cfq_group *cfqg, |
Vivek Goyal | e5ff082 | 2010-04-26 19:25:11 +0200 | [diff] [blame] | 1281 | struct cfq_queue *cfqq) |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 1282 | { |
| 1283 | struct cfq_rb_root *st = &cfqd->grp_service_tree; |
Justin TerAvest | 167400d | 2011-03-12 16:54:00 +0100 | [diff] [blame] | 1284 | unsigned int used_sl, charge, unaccounted_sl = 0; |
Vivek Goyal | f26bd1f | 2009-12-03 12:59:54 -0500 | [diff] [blame] | 1285 | int nr_sync = cfqg->nr_cfqq - cfqg_busy_async_queues(cfqd, cfqg) |
| 1286 | - cfqg->service_tree_idle.count; |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 1287 | |
Vivek Goyal | f26bd1f | 2009-12-03 12:59:54 -0500 | [diff] [blame] | 1288 | BUG_ON(nr_sync < 0); |
Justin TerAvest | 167400d | 2011-03-12 16:54:00 +0100 | [diff] [blame] | 1289 | used_sl = charge = cfq_cfqq_slice_usage(cfqq, &unaccounted_sl); |
Vivek Goyal | f26bd1f | 2009-12-03 12:59:54 -0500 | [diff] [blame] | 1290 | |
Vivek Goyal | 02b3508 | 2010-08-23 12:23:53 +0200 | [diff] [blame] | 1291 | if (iops_mode(cfqd)) |
| 1292 | charge = cfqq->slice_dispatch; |
| 1293 | else if (!cfq_cfqq_sync(cfqq) && !nr_sync) |
| 1294 | charge = cfqq->allocated_slice; |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 1295 | |
| 1296 | /* Can't update vdisktime while group is on service tree */ |
Justin TerAvest | 8184f93 | 2011-03-17 16:12:36 +0100 | [diff] [blame] | 1297 | cfq_group_service_tree_del(st, cfqg); |
Vivek Goyal | 02b3508 | 2010-08-23 12:23:53 +0200 | [diff] [blame] | 1298 | cfqg->vdisktime += cfq_scale_slice(charge, cfqg); |
Justin TerAvest | 8184f93 | 2011-03-17 16:12:36 +0100 | [diff] [blame] | 1299 | /* If a new weight was requested, update now, off tree */ |
| 1300 | cfq_group_service_tree_add(st, cfqg); |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 1301 | |
| 1302 | /* This group is being expired. Save the context */ |
| 1303 | if (time_after(cfqd->workload_expires, jiffies)) { |
| 1304 | cfqg->saved_workload_slice = cfqd->workload_expires |
| 1305 | - jiffies; |
| 1306 | cfqg->saved_workload = cfqd->serving_type; |
| 1307 | cfqg->saved_serving_prio = cfqd->serving_prio; |
| 1308 | } else |
| 1309 | cfqg->saved_workload_slice = 0; |
Vivek Goyal | 2868ef7 | 2009-12-03 12:59:48 -0500 | [diff] [blame] | 1310 | |
| 1311 | cfq_log_cfqg(cfqd, cfqg, "served: vt=%llu min_vt=%llu", cfqg->vdisktime, |
| 1312 | st->min_vdisktime); |
Joe Perches | fd16d26 | 2011-06-13 10:42:49 +0200 | [diff] [blame] | 1313 | cfq_log_cfqq(cfqq->cfqd, cfqq, |
| 1314 | "sl_used=%u disp=%u charge=%u iops=%u sect=%lu", |
| 1315 | used_sl, cfqq->slice_dispatch, charge, |
| 1316 | iops_mode(cfqd), cfqq->nr_sectors); |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1317 | cfqg_stats_update_timeslice_used(cfqg, used_sl, unaccounted_sl); |
| 1318 | cfqg_stats_set_start_empty_time(cfqg); |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 1319 | } |
| 1320 | |
Tejun Heo | f51b802 | 2012-03-05 13:15:05 -0800 | [diff] [blame] | 1321 | /** |
| 1322 | * cfq_init_cfqg_base - initialize base part of a cfq_group |
| 1323 | * @cfqg: cfq_group to initialize |
| 1324 | * |
| 1325 | * Initialize the base part which is used whether %CONFIG_CFQ_GROUP_IOSCHED |
| 1326 | * is enabled or not. |
| 1327 | */ |
| 1328 | static void cfq_init_cfqg_base(struct cfq_group *cfqg) |
| 1329 | { |
| 1330 | struct cfq_rb_root *st; |
| 1331 | int i, j; |
| 1332 | |
| 1333 | for_each_cfqg_st(cfqg, i, j, st) |
| 1334 | *st = CFQ_RB_ROOT; |
| 1335 | RB_CLEAR_NODE(&cfqg->rb_node); |
| 1336 | |
| 1337 | cfqg->ttime.last_end_request = jiffies; |
| 1338 | } |
| 1339 | |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 1340 | #ifdef CONFIG_CFQ_GROUP_IOSCHED |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1341 | static void cfq_pd_init(struct blkcg_gq *blkg) |
Vivek Goyal | f469a7b | 2011-05-19 15:38:23 -0400 | [diff] [blame] | 1342 | { |
Tejun Heo | 0381411 | 2012-03-05 13:15:14 -0800 | [diff] [blame] | 1343 | struct cfq_group *cfqg = blkg_to_cfqg(blkg); |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 1344 | |
Tejun Heo | f51b802 | 2012-03-05 13:15:05 -0800 | [diff] [blame] | 1345 | cfq_init_cfqg_base(cfqg); |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1346 | cfqg->weight = blkg->blkcg->cfq_weight; |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 1347 | } |
| 1348 | |
| 1349 | /* |
Vivek Goyal | 3e59cf9 | 2011-05-19 15:38:21 -0400 | [diff] [blame] | 1350 | * Search for the cfq group current task belongs to. request_queue lock must |
| 1351 | * be held. |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 1352 | */ |
Tejun Heo | cd1604f | 2012-03-05 13:15:06 -0800 | [diff] [blame] | 1353 | static struct cfq_group *cfq_lookup_create_cfqg(struct cfq_data *cfqd, |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1354 | struct blkcg *blkcg) |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 1355 | { |
Vivek Goyal | f469a7b | 2011-05-19 15:38:23 -0400 | [diff] [blame] | 1356 | struct request_queue *q = cfqd->queue; |
Tejun Heo | cd1604f | 2012-03-05 13:15:06 -0800 | [diff] [blame] | 1357 | struct cfq_group *cfqg = NULL; |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 1358 | |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1359 | /* avoid lookup for the common case where there's no blkcg */ |
| 1360 | if (blkcg == &blkcg_root) { |
Tejun Heo | cd1604f | 2012-03-05 13:15:06 -0800 | [diff] [blame] | 1361 | cfqg = cfqd->root_group; |
| 1362 | } else { |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1363 | struct blkcg_gq *blkg; |
Vivek Goyal | f469a7b | 2011-05-19 15:38:23 -0400 | [diff] [blame] | 1364 | |
Tejun Heo | 3c96cb3 | 2012-04-13 13:11:34 -0700 | [diff] [blame] | 1365 | blkg = blkg_lookup_create(blkcg, q); |
Tejun Heo | cd1604f | 2012-03-05 13:15:06 -0800 | [diff] [blame] | 1366 | if (!IS_ERR(blkg)) |
Tejun Heo | 0381411 | 2012-03-05 13:15:14 -0800 | [diff] [blame] | 1367 | cfqg = blkg_to_cfqg(blkg); |
Vivek Goyal | f469a7b | 2011-05-19 15:38:23 -0400 | [diff] [blame] | 1368 | } |
| 1369 | |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 1370 | return cfqg; |
| 1371 | } |
| 1372 | |
| 1373 | static void cfq_link_cfqq_cfqg(struct cfq_queue *cfqq, struct cfq_group *cfqg) |
| 1374 | { |
| 1375 | /* Currently, all async queues are mapped to root group */ |
| 1376 | if (!cfq_cfqq_sync(cfqq)) |
Tejun Heo | f51b802 | 2012-03-05 13:15:05 -0800 | [diff] [blame] | 1377 | cfqg = cfqq->cfqd->root_group; |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 1378 | |
| 1379 | cfqq->cfqg = cfqg; |
Vivek Goyal | b1c3576 | 2009-12-03 12:59:47 -0500 | [diff] [blame] | 1380 | /* cfqq reference on cfqg */ |
Tejun Heo | eb7d8c07 | 2012-03-23 14:02:53 +0100 | [diff] [blame] | 1381 | cfqg_get(cfqg); |
Vivek Goyal | b1c3576 | 2009-12-03 12:59:47 -0500 | [diff] [blame] | 1382 | } |
| 1383 | |
Tejun Heo | f95a04a | 2012-04-16 13:57:26 -0700 | [diff] [blame] | 1384 | static u64 cfqg_prfill_weight_device(struct seq_file *sf, |
| 1385 | struct blkg_policy_data *pd, int off) |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1386 | { |
Tejun Heo | f95a04a | 2012-04-16 13:57:26 -0700 | [diff] [blame] | 1387 | struct cfq_group *cfqg = pd_to_cfqg(pd); |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1388 | |
| 1389 | if (!cfqg->dev_weight) |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1390 | return 0; |
Tejun Heo | f95a04a | 2012-04-16 13:57:26 -0700 | [diff] [blame] | 1391 | return __blkg_prfill_u64(sf, pd, cfqg->dev_weight); |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1392 | } |
| 1393 | |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1394 | static int cfqg_print_weight_device(struct cgroup *cgrp, struct cftype *cft, |
| 1395 | struct seq_file *sf) |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1396 | { |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1397 | blkcg_print_blkgs(sf, cgroup_to_blkcg(cgrp), |
| 1398 | cfqg_prfill_weight_device, &blkcg_policy_cfq, 0, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1399 | false); |
| 1400 | return 0; |
| 1401 | } |
| 1402 | |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1403 | static int cfq_print_weight(struct cgroup *cgrp, struct cftype *cft, |
| 1404 | struct seq_file *sf) |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1405 | { |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1406 | seq_printf(sf, "%u\n", cgroup_to_blkcg(cgrp)->cfq_weight); |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1407 | return 0; |
| 1408 | } |
| 1409 | |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1410 | static int cfqg_set_weight_device(struct cgroup *cgrp, struct cftype *cft, |
| 1411 | const char *buf) |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1412 | { |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1413 | struct blkcg *blkcg = cgroup_to_blkcg(cgrp); |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1414 | struct blkg_conf_ctx ctx; |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1415 | struct cfq_group *cfqg; |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1416 | int ret; |
| 1417 | |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1418 | ret = blkg_conf_prep(blkcg, &blkcg_policy_cfq, buf, &ctx); |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1419 | if (ret) |
| 1420 | return ret; |
| 1421 | |
| 1422 | ret = -EINVAL; |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1423 | cfqg = blkg_to_cfqg(ctx.blkg); |
Tejun Heo | a2b1693 | 2012-04-13 13:11:33 -0700 | [diff] [blame] | 1424 | if (!ctx.v || (ctx.v >= CFQ_WEIGHT_MIN && ctx.v <= CFQ_WEIGHT_MAX)) { |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1425 | cfqg->dev_weight = ctx.v; |
| 1426 | cfqg->new_weight = cfqg->dev_weight ?: blkcg->cfq_weight; |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1427 | ret = 0; |
| 1428 | } |
| 1429 | |
| 1430 | blkg_conf_finish(&ctx); |
| 1431 | return ret; |
| 1432 | } |
| 1433 | |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1434 | static int cfq_set_weight(struct cgroup *cgrp, struct cftype *cft, u64 val) |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1435 | { |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1436 | struct blkcg *blkcg = cgroup_to_blkcg(cgrp); |
| 1437 | struct blkcg_gq *blkg; |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1438 | struct hlist_node *n; |
| 1439 | |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1440 | if (val < CFQ_WEIGHT_MIN || val > CFQ_WEIGHT_MAX) |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1441 | return -EINVAL; |
| 1442 | |
| 1443 | spin_lock_irq(&blkcg->lock); |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1444 | blkcg->cfq_weight = (unsigned int)val; |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1445 | |
| 1446 | hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) { |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1447 | struct cfq_group *cfqg = blkg_to_cfqg(blkg); |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1448 | |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1449 | if (cfqg && !cfqg->dev_weight) |
| 1450 | cfqg->new_weight = blkcg->cfq_weight; |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1451 | } |
| 1452 | |
| 1453 | spin_unlock_irq(&blkcg->lock); |
| 1454 | return 0; |
| 1455 | } |
| 1456 | |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1457 | static int cfqg_print_stat(struct cgroup *cgrp, struct cftype *cft, |
| 1458 | struct seq_file *sf) |
| 1459 | { |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1460 | struct blkcg *blkcg = cgroup_to_blkcg(cgrp); |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1461 | |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1462 | blkcg_print_blkgs(sf, blkcg, blkg_prfill_stat, &blkcg_policy_cfq, |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1463 | cft->private, false); |
| 1464 | return 0; |
| 1465 | } |
| 1466 | |
| 1467 | static int cfqg_print_rwstat(struct cgroup *cgrp, struct cftype *cft, |
| 1468 | struct seq_file *sf) |
| 1469 | { |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1470 | struct blkcg *blkcg = cgroup_to_blkcg(cgrp); |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1471 | |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1472 | blkcg_print_blkgs(sf, blkcg, blkg_prfill_rwstat, &blkcg_policy_cfq, |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1473 | cft->private, true); |
| 1474 | return 0; |
| 1475 | } |
| 1476 | |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1477 | #ifdef CONFIG_DEBUG_BLK_CGROUP |
Tejun Heo | f95a04a | 2012-04-16 13:57:26 -0700 | [diff] [blame] | 1478 | static u64 cfqg_prfill_avg_queue_size(struct seq_file *sf, |
| 1479 | struct blkg_policy_data *pd, int off) |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1480 | { |
Tejun Heo | f95a04a | 2012-04-16 13:57:26 -0700 | [diff] [blame] | 1481 | struct cfq_group *cfqg = pd_to_cfqg(pd); |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1482 | u64 samples = blkg_stat_read(&cfqg->stats.avg_queue_size_samples); |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1483 | u64 v = 0; |
| 1484 | |
| 1485 | if (samples) { |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1486 | v = blkg_stat_read(&cfqg->stats.avg_queue_size_sum); |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1487 | do_div(v, samples); |
| 1488 | } |
Tejun Heo | f95a04a | 2012-04-16 13:57:26 -0700 | [diff] [blame] | 1489 | __blkg_prfill_u64(sf, pd, v); |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1490 | return 0; |
| 1491 | } |
| 1492 | |
| 1493 | /* print avg_queue_size */ |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1494 | static int cfqg_print_avg_queue_size(struct cgroup *cgrp, struct cftype *cft, |
| 1495 | struct seq_file *sf) |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1496 | { |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1497 | struct blkcg *blkcg = cgroup_to_blkcg(cgrp); |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1498 | |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1499 | blkcg_print_blkgs(sf, blkcg, cfqg_prfill_avg_queue_size, |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1500 | &blkcg_policy_cfq, 0, false); |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1501 | return 0; |
| 1502 | } |
| 1503 | #endif /* CONFIG_DEBUG_BLK_CGROUP */ |
| 1504 | |
| 1505 | static struct cftype cfq_blkcg_files[] = { |
| 1506 | { |
| 1507 | .name = "weight_device", |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1508 | .read_seq_string = cfqg_print_weight_device, |
| 1509 | .write_string = cfqg_set_weight_device, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1510 | .max_write_len = 256, |
| 1511 | }, |
| 1512 | { |
| 1513 | .name = "weight", |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1514 | .read_seq_string = cfq_print_weight, |
| 1515 | .write_u64 = cfq_set_weight, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1516 | }, |
| 1517 | { |
| 1518 | .name = "time", |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1519 | .private = offsetof(struct cfq_group, stats.time), |
| 1520 | .read_seq_string = cfqg_print_stat, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1521 | }, |
| 1522 | { |
| 1523 | .name = "sectors", |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1524 | .private = offsetof(struct cfq_group, stats.sectors), |
| 1525 | .read_seq_string = cfqg_print_stat, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1526 | }, |
| 1527 | { |
| 1528 | .name = "io_service_bytes", |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1529 | .private = offsetof(struct cfq_group, stats.service_bytes), |
| 1530 | .read_seq_string = cfqg_print_rwstat, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1531 | }, |
| 1532 | { |
| 1533 | .name = "io_serviced", |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1534 | .private = offsetof(struct cfq_group, stats.serviced), |
| 1535 | .read_seq_string = cfqg_print_rwstat, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1536 | }, |
| 1537 | { |
| 1538 | .name = "io_service_time", |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1539 | .private = offsetof(struct cfq_group, stats.service_time), |
| 1540 | .read_seq_string = cfqg_print_rwstat, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1541 | }, |
| 1542 | { |
| 1543 | .name = "io_wait_time", |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1544 | .private = offsetof(struct cfq_group, stats.wait_time), |
| 1545 | .read_seq_string = cfqg_print_rwstat, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1546 | }, |
| 1547 | { |
| 1548 | .name = "io_merged", |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1549 | .private = offsetof(struct cfq_group, stats.merged), |
| 1550 | .read_seq_string = cfqg_print_rwstat, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1551 | }, |
| 1552 | { |
| 1553 | .name = "io_queued", |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1554 | .private = offsetof(struct cfq_group, stats.queued), |
| 1555 | .read_seq_string = cfqg_print_rwstat, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1556 | }, |
| 1557 | #ifdef CONFIG_DEBUG_BLK_CGROUP |
| 1558 | { |
| 1559 | .name = "avg_queue_size", |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1560 | .read_seq_string = cfqg_print_avg_queue_size, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1561 | }, |
| 1562 | { |
| 1563 | .name = "group_wait_time", |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1564 | .private = offsetof(struct cfq_group, stats.group_wait_time), |
| 1565 | .read_seq_string = cfqg_print_stat, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1566 | }, |
| 1567 | { |
| 1568 | .name = "idle_time", |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1569 | .private = offsetof(struct cfq_group, stats.idle_time), |
| 1570 | .read_seq_string = cfqg_print_stat, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1571 | }, |
| 1572 | { |
| 1573 | .name = "empty_time", |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1574 | .private = offsetof(struct cfq_group, stats.empty_time), |
| 1575 | .read_seq_string = cfqg_print_stat, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1576 | }, |
| 1577 | { |
| 1578 | .name = "dequeue", |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1579 | .private = offsetof(struct cfq_group, stats.dequeue), |
| 1580 | .read_seq_string = cfqg_print_stat, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1581 | }, |
| 1582 | { |
| 1583 | .name = "unaccounted_time", |
Tejun Heo | 5bc4afb1 | 2012-04-01 14:38:45 -0700 | [diff] [blame] | 1584 | .private = offsetof(struct cfq_group, stats.unaccounted_time), |
| 1585 | .read_seq_string = cfqg_print_stat, |
Tejun Heo | 60c2bc2 | 2012-04-01 14:38:43 -0700 | [diff] [blame] | 1586 | }, |
| 1587 | #endif /* CONFIG_DEBUG_BLK_CGROUP */ |
| 1588 | { } /* terminate */ |
| 1589 | }; |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 1590 | #else /* GROUP_IOSCHED */ |
Tejun Heo | cd1604f | 2012-03-05 13:15:06 -0800 | [diff] [blame] | 1591 | static struct cfq_group *cfq_lookup_create_cfqg(struct cfq_data *cfqd, |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 1592 | struct blkcg *blkcg) |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 1593 | { |
Tejun Heo | f51b802 | 2012-03-05 13:15:05 -0800 | [diff] [blame] | 1594 | return cfqd->root_group; |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 1595 | } |
Vivek Goyal | 7f1dc8a | 2010-04-21 17:44:16 +0200 | [diff] [blame] | 1596 | |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 1597 | static inline void |
| 1598 | cfq_link_cfqq_cfqg(struct cfq_queue *cfqq, struct cfq_group *cfqg) { |
| 1599 | cfqq->cfqg = cfqg; |
| 1600 | } |
| 1601 | |
| 1602 | #endif /* GROUP_IOSCHED */ |
| 1603 | |
Jens Axboe | 498d3aa2 | 2007-04-26 12:54:48 +0200 | [diff] [blame] | 1604 | /* |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 1605 | * The cfqd->service_trees holds all pending cfq_queue's that have |
Jens Axboe | 498d3aa2 | 2007-04-26 12:54:48 +0200 | [diff] [blame] | 1606 | * requests waiting to be processed. It is sorted in the order that |
| 1607 | * we will service the queues. |
| 1608 | */ |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1609 | static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq, |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 1610 | bool add_front) |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 1611 | { |
Jens Axboe | 0871714 | 2008-01-28 11:38:15 +0100 | [diff] [blame] | 1612 | struct rb_node **p, *parent; |
| 1613 | struct cfq_queue *__cfqq; |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 1614 | unsigned long rb_key; |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 1615 | struct cfq_rb_root *service_tree; |
Jens Axboe | 498d3aa2 | 2007-04-26 12:54:48 +0200 | [diff] [blame] | 1616 | int left; |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 1617 | int new_cfqq = 1; |
Vivek Goyal | ae30c28 | 2009-12-03 12:59:55 -0500 | [diff] [blame] | 1618 | |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 1619 | service_tree = service_tree_for(cfqq->cfqg, cfqq_prio(cfqq), |
Vivek Goyal | 65b32a5 | 2009-12-16 17:52:59 -0500 | [diff] [blame] | 1620 | cfqq_type(cfqq)); |
Jens Axboe | 0871714 | 2008-01-28 11:38:15 +0100 | [diff] [blame] | 1621 | if (cfq_class_idle(cfqq)) { |
| 1622 | rb_key = CFQ_IDLE_DELAY; |
Corrado Zoccolo | aa6f6a3 | 2009-10-26 22:44:33 +0100 | [diff] [blame] | 1623 | parent = rb_last(&service_tree->rb); |
Jens Axboe | 0871714 | 2008-01-28 11:38:15 +0100 | [diff] [blame] | 1624 | if (parent && parent != &cfqq->rb_node) { |
| 1625 | __cfqq = rb_entry(parent, struct cfq_queue, rb_node); |
| 1626 | rb_key += __cfqq->rb_key; |
| 1627 | } else |
| 1628 | rb_key += jiffies; |
| 1629 | } else if (!add_front) { |
Jens Axboe | b9c8946 | 2009-10-06 20:53:44 +0200 | [diff] [blame] | 1630 | /* |
| 1631 | * Get our rb key offset. Subtract any residual slice |
| 1632 | * value carried from last service. A negative resid |
| 1633 | * count indicates slice overrun, and this should position |
| 1634 | * the next service time further away in the tree. |
| 1635 | */ |
Jens Axboe | edd75ff | 2007-04-19 12:03:34 +0200 | [diff] [blame] | 1636 | rb_key = cfq_slice_offset(cfqd, cfqq) + jiffies; |
Jens Axboe | b9c8946 | 2009-10-06 20:53:44 +0200 | [diff] [blame] | 1637 | rb_key -= cfqq->slice_resid; |
Jens Axboe | edd75ff | 2007-04-19 12:03:34 +0200 | [diff] [blame] | 1638 | cfqq->slice_resid = 0; |
Corrado Zoccolo | 48e025e | 2009-10-05 08:49:23 +0200 | [diff] [blame] | 1639 | } else { |
| 1640 | rb_key = -HZ; |
Corrado Zoccolo | aa6f6a3 | 2009-10-26 22:44:33 +0100 | [diff] [blame] | 1641 | __cfqq = cfq_rb_first(service_tree); |
Corrado Zoccolo | 48e025e | 2009-10-05 08:49:23 +0200 | [diff] [blame] | 1642 | rb_key += __cfqq ? __cfqq->rb_key : jiffies; |
| 1643 | } |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 1644 | |
| 1645 | if (!RB_EMPTY_NODE(&cfqq->rb_node)) { |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 1646 | new_cfqq = 0; |
Jens Axboe | 99f9628 | 2007-02-05 11:56:25 +0100 | [diff] [blame] | 1647 | /* |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 1648 | * same position, nothing more to do |
Jens Axboe | 99f9628 | 2007-02-05 11:56:25 +0100 | [diff] [blame] | 1649 | */ |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 1650 | if (rb_key == cfqq->rb_key && |
| 1651 | cfqq->service_tree == service_tree) |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 1652 | return; |
Jens Axboe | 53b03744 | 2006-07-28 09:48:51 +0200 | [diff] [blame] | 1653 | |
Corrado Zoccolo | aa6f6a3 | 2009-10-26 22:44:33 +0100 | [diff] [blame] | 1654 | cfq_rb_erase(&cfqq->rb_node, cfqq->service_tree); |
| 1655 | cfqq->service_tree = NULL; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 1656 | } |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 1657 | |
Jens Axboe | 498d3aa2 | 2007-04-26 12:54:48 +0200 | [diff] [blame] | 1658 | left = 1; |
Jens Axboe | 0871714 | 2008-01-28 11:38:15 +0100 | [diff] [blame] | 1659 | parent = NULL; |
Corrado Zoccolo | aa6f6a3 | 2009-10-26 22:44:33 +0100 | [diff] [blame] | 1660 | cfqq->service_tree = service_tree; |
| 1661 | p = &service_tree->rb.rb_node; |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 1662 | while (*p) { |
Jens Axboe | 67060e3 | 2007-04-18 20:13:32 +0200 | [diff] [blame] | 1663 | struct rb_node **n; |
Jens Axboe | cc09e29 | 2007-04-26 12:53:50 +0200 | [diff] [blame] | 1664 | |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 1665 | parent = *p; |
| 1666 | __cfqq = rb_entry(parent, struct cfq_queue, rb_node); |
| 1667 | |
Jens Axboe | 0c534e0 | 2007-04-18 20:01:57 +0200 | [diff] [blame] | 1668 | /* |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 1669 | * sort by key, that represents service time. |
Jens Axboe | 0c534e0 | 2007-04-18 20:01:57 +0200 | [diff] [blame] | 1670 | */ |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 1671 | if (time_before(rb_key, __cfqq->rb_key)) |
Jens Axboe | 67060e3 | 2007-04-18 20:13:32 +0200 | [diff] [blame] | 1672 | n = &(*p)->rb_left; |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 1673 | else { |
Jens Axboe | 67060e3 | 2007-04-18 20:13:32 +0200 | [diff] [blame] | 1674 | n = &(*p)->rb_right; |
Jens Axboe | cc09e29 | 2007-04-26 12:53:50 +0200 | [diff] [blame] | 1675 | left = 0; |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 1676 | } |
Jens Axboe | 67060e3 | 2007-04-18 20:13:32 +0200 | [diff] [blame] | 1677 | |
| 1678 | p = n; |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 1679 | } |
| 1680 | |
Jens Axboe | cc09e29 | 2007-04-26 12:53:50 +0200 | [diff] [blame] | 1681 | if (left) |
Corrado Zoccolo | aa6f6a3 | 2009-10-26 22:44:33 +0100 | [diff] [blame] | 1682 | service_tree->left = &cfqq->rb_node; |
Jens Axboe | cc09e29 | 2007-04-26 12:53:50 +0200 | [diff] [blame] | 1683 | |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 1684 | cfqq->rb_key = rb_key; |
| 1685 | rb_link_node(&cfqq->rb_node, parent, p); |
Corrado Zoccolo | aa6f6a3 | 2009-10-26 22:44:33 +0100 | [diff] [blame] | 1686 | rb_insert_color(&cfqq->rb_node, &service_tree->rb); |
| 1687 | service_tree->count++; |
Namhyung Kim | 20359f2 | 2011-05-24 10:23:22 +0200 | [diff] [blame] | 1688 | if (add_front || !new_cfqq) |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 1689 | return; |
Justin TerAvest | 8184f93 | 2011-03-17 16:12:36 +0100 | [diff] [blame] | 1690 | cfq_group_notify_queue_add(cfqd, cfqq->cfqg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1691 | } |
| 1692 | |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1693 | static struct cfq_queue * |
Jens Axboe | f2d1f0a | 2009-04-23 12:19:38 +0200 | [diff] [blame] | 1694 | cfq_prio_tree_lookup(struct cfq_data *cfqd, struct rb_root *root, |
| 1695 | sector_t sector, struct rb_node **ret_parent, |
| 1696 | struct rb_node ***rb_link) |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1697 | { |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1698 | struct rb_node **p, *parent; |
| 1699 | struct cfq_queue *cfqq = NULL; |
| 1700 | |
| 1701 | parent = NULL; |
| 1702 | p = &root->rb_node; |
| 1703 | while (*p) { |
| 1704 | struct rb_node **n; |
| 1705 | |
| 1706 | parent = *p; |
| 1707 | cfqq = rb_entry(parent, struct cfq_queue, p_node); |
| 1708 | |
| 1709 | /* |
| 1710 | * Sort strictly based on sector. Smallest to the left, |
| 1711 | * largest to the right. |
| 1712 | */ |
Tejun Heo | 2e46e8b | 2009-05-07 22:24:41 +0900 | [diff] [blame] | 1713 | if (sector > blk_rq_pos(cfqq->next_rq)) |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1714 | n = &(*p)->rb_right; |
Tejun Heo | 2e46e8b | 2009-05-07 22:24:41 +0900 | [diff] [blame] | 1715 | else if (sector < blk_rq_pos(cfqq->next_rq)) |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1716 | n = &(*p)->rb_left; |
| 1717 | else |
| 1718 | break; |
| 1719 | p = n; |
Jens Axboe | 3ac6c9f | 2009-04-23 12:14:56 +0200 | [diff] [blame] | 1720 | cfqq = NULL; |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1721 | } |
| 1722 | |
| 1723 | *ret_parent = parent; |
| 1724 | if (rb_link) |
| 1725 | *rb_link = p; |
Jens Axboe | 3ac6c9f | 2009-04-23 12:14:56 +0200 | [diff] [blame] | 1726 | return cfqq; |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1727 | } |
| 1728 | |
| 1729 | static void cfq_prio_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
| 1730 | { |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1731 | struct rb_node **p, *parent; |
| 1732 | struct cfq_queue *__cfqq; |
| 1733 | |
Jens Axboe | f2d1f0a | 2009-04-23 12:19:38 +0200 | [diff] [blame] | 1734 | if (cfqq->p_root) { |
| 1735 | rb_erase(&cfqq->p_node, cfqq->p_root); |
| 1736 | cfqq->p_root = NULL; |
| 1737 | } |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1738 | |
| 1739 | if (cfq_class_idle(cfqq)) |
| 1740 | return; |
| 1741 | if (!cfqq->next_rq) |
| 1742 | return; |
| 1743 | |
Jens Axboe | f2d1f0a | 2009-04-23 12:19:38 +0200 | [diff] [blame] | 1744 | cfqq->p_root = &cfqd->prio_trees[cfqq->org_ioprio]; |
Tejun Heo | 2e46e8b | 2009-05-07 22:24:41 +0900 | [diff] [blame] | 1745 | __cfqq = cfq_prio_tree_lookup(cfqd, cfqq->p_root, |
| 1746 | blk_rq_pos(cfqq->next_rq), &parent, &p); |
Jens Axboe | 3ac6c9f | 2009-04-23 12:14:56 +0200 | [diff] [blame] | 1747 | if (!__cfqq) { |
| 1748 | rb_link_node(&cfqq->p_node, parent, p); |
Jens Axboe | f2d1f0a | 2009-04-23 12:19:38 +0200 | [diff] [blame] | 1749 | rb_insert_color(&cfqq->p_node, cfqq->p_root); |
| 1750 | } else |
| 1751 | cfqq->p_root = NULL; |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1752 | } |
| 1753 | |
Jens Axboe | 498d3aa2 | 2007-04-26 12:54:48 +0200 | [diff] [blame] | 1754 | /* |
| 1755 | * Update cfqq's position in the service tree. |
| 1756 | */ |
Jens Axboe | edd75ff | 2007-04-19 12:03:34 +0200 | [diff] [blame] | 1757 | static void cfq_resort_rr_list(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 1758 | { |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 1759 | /* |
| 1760 | * Resorting requires the cfqq to be on the RR list already. |
| 1761 | */ |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1762 | if (cfq_cfqq_on_rr(cfqq)) { |
Jens Axboe | edd75ff | 2007-04-19 12:03:34 +0200 | [diff] [blame] | 1763 | cfq_service_tree_add(cfqd, cfqq, 0); |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1764 | cfq_prio_tree_add(cfqd, cfqq); |
| 1765 | } |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 1766 | } |
| 1767 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1768 | /* |
| 1769 | * add to busy list of queues for service, trying to be fair in ordering |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 1770 | * the pending list according to last request service |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1771 | */ |
Jens Axboe | febffd6 | 2008-01-28 13:19:43 +0100 | [diff] [blame] | 1772 | static void cfq_add_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1773 | { |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 1774 | cfq_log_cfqq(cfqd, cfqq, "add_to_rr"); |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 1775 | BUG_ON(cfq_cfqq_on_rr(cfqq)); |
| 1776 | cfq_mark_cfqq_on_rr(cfqq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1777 | cfqd->busy_queues++; |
Shaohua Li | ef8a41d | 2011-03-07 09:26:29 +0100 | [diff] [blame] | 1778 | if (cfq_cfqq_sync(cfqq)) |
| 1779 | cfqd->busy_sync_queues++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1780 | |
Jens Axboe | edd75ff | 2007-04-19 12:03:34 +0200 | [diff] [blame] | 1781 | cfq_resort_rr_list(cfqd, cfqq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1782 | } |
| 1783 | |
Jens Axboe | 498d3aa2 | 2007-04-26 12:54:48 +0200 | [diff] [blame] | 1784 | /* |
| 1785 | * Called when the cfqq no longer has requests pending, remove it from |
| 1786 | * the service tree. |
| 1787 | */ |
Jens Axboe | febffd6 | 2008-01-28 13:19:43 +0100 | [diff] [blame] | 1788 | static void cfq_del_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1789 | { |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 1790 | cfq_log_cfqq(cfqd, cfqq, "del_from_rr"); |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 1791 | BUG_ON(!cfq_cfqq_on_rr(cfqq)); |
| 1792 | cfq_clear_cfqq_on_rr(cfqq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1793 | |
Corrado Zoccolo | aa6f6a3 | 2009-10-26 22:44:33 +0100 | [diff] [blame] | 1794 | if (!RB_EMPTY_NODE(&cfqq->rb_node)) { |
| 1795 | cfq_rb_erase(&cfqq->rb_node, cfqq->service_tree); |
| 1796 | cfqq->service_tree = NULL; |
| 1797 | } |
Jens Axboe | f2d1f0a | 2009-04-23 12:19:38 +0200 | [diff] [blame] | 1798 | if (cfqq->p_root) { |
| 1799 | rb_erase(&cfqq->p_node, cfqq->p_root); |
| 1800 | cfqq->p_root = NULL; |
| 1801 | } |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 1802 | |
Justin TerAvest | 8184f93 | 2011-03-17 16:12:36 +0100 | [diff] [blame] | 1803 | cfq_group_notify_queue_del(cfqd, cfqq->cfqg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1804 | BUG_ON(!cfqd->busy_queues); |
| 1805 | cfqd->busy_queues--; |
Shaohua Li | ef8a41d | 2011-03-07 09:26:29 +0100 | [diff] [blame] | 1806 | if (cfq_cfqq_sync(cfqq)) |
| 1807 | cfqd->busy_sync_queues--; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1808 | } |
| 1809 | |
| 1810 | /* |
| 1811 | * rb tree support functions |
| 1812 | */ |
Jens Axboe | febffd6 | 2008-01-28 13:19:43 +0100 | [diff] [blame] | 1813 | static void cfq_del_rq_rb(struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1814 | { |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1815 | struct cfq_queue *cfqq = RQ_CFQQ(rq); |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1816 | const int sync = rq_is_sync(rq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1817 | |
Jens Axboe | b4878f2 | 2005-10-20 16:42:29 +0200 | [diff] [blame] | 1818 | BUG_ON(!cfqq->queued[sync]); |
| 1819 | cfqq->queued[sync]--; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1820 | |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1821 | elv_rb_del(&cfqq->sort_list, rq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1822 | |
Vivek Goyal | f04a642 | 2009-12-03 12:59:40 -0500 | [diff] [blame] | 1823 | if (cfq_cfqq_on_rr(cfqq) && RB_EMPTY_ROOT(&cfqq->sort_list)) { |
| 1824 | /* |
| 1825 | * Queue will be deleted from service tree when we actually |
| 1826 | * expire it later. Right now just remove it from prio tree |
| 1827 | * as it is empty. |
| 1828 | */ |
| 1829 | if (cfqq->p_root) { |
| 1830 | rb_erase(&cfqq->p_node, cfqq->p_root); |
| 1831 | cfqq->p_root = NULL; |
| 1832 | } |
| 1833 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1834 | } |
| 1835 | |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1836 | static void cfq_add_rq_rb(struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1837 | { |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1838 | struct cfq_queue *cfqq = RQ_CFQQ(rq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1839 | struct cfq_data *cfqd = cfqq->cfqd; |
Jeff Moyer | 796d511 | 2011-06-02 21:19:05 +0200 | [diff] [blame] | 1840 | struct request *prev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1841 | |
Jens Axboe | 5380a10 | 2006-07-13 12:37:56 +0200 | [diff] [blame] | 1842 | cfqq->queued[rq_is_sync(rq)]++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1843 | |
Jeff Moyer | 796d511 | 2011-06-02 21:19:05 +0200 | [diff] [blame] | 1844 | elv_rb_add(&cfqq->sort_list, rq); |
Jens Axboe | 5fccbf6 | 2006-10-31 14:21:55 +0100 | [diff] [blame] | 1845 | |
| 1846 | if (!cfq_cfqq_on_rr(cfqq)) |
| 1847 | cfq_add_cfqq_rr(cfqd, cfqq); |
Jens Axboe | 5044eed | 2007-04-25 11:53:48 +0200 | [diff] [blame] | 1848 | |
| 1849 | /* |
| 1850 | * check if this request is a better next-serve candidate |
| 1851 | */ |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1852 | prev = cfqq->next_rq; |
Corrado Zoccolo | cf7c25c | 2009-11-08 17:16:46 +0100 | [diff] [blame] | 1853 | cfqq->next_rq = cfq_choose_req(cfqd, cfqq->next_rq, rq, cfqd->last_position); |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 1854 | |
| 1855 | /* |
| 1856 | * adjust priority tree position, if ->next_rq changes |
| 1857 | */ |
| 1858 | if (prev != cfqq->next_rq) |
| 1859 | cfq_prio_tree_add(cfqd, cfqq); |
| 1860 | |
Jens Axboe | 5044eed | 2007-04-25 11:53:48 +0200 | [diff] [blame] | 1861 | BUG_ON(!cfqq->next_rq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1862 | } |
| 1863 | |
Jens Axboe | febffd6 | 2008-01-28 13:19:43 +0100 | [diff] [blame] | 1864 | static void cfq_reposition_rq_rb(struct cfq_queue *cfqq, struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1865 | { |
Jens Axboe | 5380a10 | 2006-07-13 12:37:56 +0200 | [diff] [blame] | 1866 | elv_rb_del(&cfqq->sort_list, rq); |
| 1867 | cfqq->queued[rq_is_sync(rq)]--; |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1868 | cfqg_stats_update_io_remove(RQ_CFQG(rq), rq->cmd_flags); |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1869 | cfq_add_rq_rb(rq); |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1870 | cfqg_stats_update_io_add(RQ_CFQG(rq), cfqq->cfqd->serving_group, |
| 1871 | rq->cmd_flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1872 | } |
| 1873 | |
Jens Axboe | 206dc69 | 2006-03-28 13:03:44 +0200 | [diff] [blame] | 1874 | static struct request * |
| 1875 | cfq_find_rq_fmerge(struct cfq_data *cfqd, struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1876 | { |
Jens Axboe | 206dc69 | 2006-03-28 13:03:44 +0200 | [diff] [blame] | 1877 | struct task_struct *tsk = current; |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 1878 | struct cfq_io_cq *cic; |
Jens Axboe | 206dc69 | 2006-03-28 13:03:44 +0200 | [diff] [blame] | 1879 | struct cfq_queue *cfqq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1880 | |
Jens Axboe | 4ac845a | 2008-01-24 08:44:49 +0100 | [diff] [blame] | 1881 | cic = cfq_cic_lookup(cfqd, tsk->io_context); |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 1882 | if (!cic) |
| 1883 | return NULL; |
| 1884 | |
| 1885 | cfqq = cic_to_cfqq(cic, cfq_bio_sync(bio)); |
Jens Axboe | 89850f7 | 2006-07-22 16:48:31 +0200 | [diff] [blame] | 1886 | if (cfqq) { |
| 1887 | sector_t sector = bio->bi_sector + bio_sectors(bio); |
| 1888 | |
Jens Axboe | 21183b0 | 2006-07-13 12:33:14 +0200 | [diff] [blame] | 1889 | return elv_rb_find(&cfqq->sort_list, sector); |
Jens Axboe | 89850f7 | 2006-07-22 16:48:31 +0200 | [diff] [blame] | 1890 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1891 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1892 | return NULL; |
| 1893 | } |
| 1894 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1895 | static void cfq_activate_request(struct request_queue *q, struct request *rq) |
Jens Axboe | b4878f2 | 2005-10-20 16:42:29 +0200 | [diff] [blame] | 1896 | { |
| 1897 | struct cfq_data *cfqd = q->elevator->elevator_data; |
| 1898 | |
Corrado Zoccolo | 53c583d | 2010-02-28 19:45:05 +0100 | [diff] [blame] | 1899 | cfqd->rq_in_driver++; |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 1900 | cfq_log_cfqq(cfqd, RQ_CFQQ(rq), "activate rq, drv=%d", |
Corrado Zoccolo | 53c583d | 2010-02-28 19:45:05 +0100 | [diff] [blame] | 1901 | cfqd->rq_in_driver); |
Jens Axboe | 25776e3 | 2006-06-01 10:12:26 +0200 | [diff] [blame] | 1902 | |
Tejun Heo | 5b93629 | 2009-05-07 22:24:38 +0900 | [diff] [blame] | 1903 | cfqd->last_position = blk_rq_pos(rq) + blk_rq_sectors(rq); |
Jens Axboe | b4878f2 | 2005-10-20 16:42:29 +0200 | [diff] [blame] | 1904 | } |
| 1905 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1906 | static void cfq_deactivate_request(struct request_queue *q, struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1907 | { |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 1908 | struct cfq_data *cfqd = q->elevator->elevator_data; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1909 | |
Corrado Zoccolo | 53c583d | 2010-02-28 19:45:05 +0100 | [diff] [blame] | 1910 | WARN_ON(!cfqd->rq_in_driver); |
| 1911 | cfqd->rq_in_driver--; |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 1912 | cfq_log_cfqq(cfqd, RQ_CFQQ(rq), "deactivate rq, drv=%d", |
Corrado Zoccolo | 53c583d | 2010-02-28 19:45:05 +0100 | [diff] [blame] | 1913 | cfqd->rq_in_driver); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1914 | } |
| 1915 | |
Jens Axboe | b4878f2 | 2005-10-20 16:42:29 +0200 | [diff] [blame] | 1916 | static void cfq_remove_request(struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1917 | { |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1918 | struct cfq_queue *cfqq = RQ_CFQQ(rq); |
Jens Axboe | 21183b0 | 2006-07-13 12:33:14 +0200 | [diff] [blame] | 1919 | |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1920 | if (cfqq->next_rq == rq) |
| 1921 | cfqq->next_rq = cfq_find_next_rq(cfqq->cfqd, cfqq, rq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1922 | |
Jens Axboe | b4878f2 | 2005-10-20 16:42:29 +0200 | [diff] [blame] | 1923 | list_del_init(&rq->queuelist); |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1924 | cfq_del_rq_rb(rq); |
Jens Axboe | 374f84a | 2006-07-23 01:42:19 +0200 | [diff] [blame] | 1925 | |
Aaron Carroll | 45333d5 | 2008-08-26 15:52:36 +0200 | [diff] [blame] | 1926 | cfqq->cfqd->rq_queued--; |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1927 | cfqg_stats_update_io_remove(RQ_CFQG(rq), rq->cmd_flags); |
Christoph Hellwig | 65299a3 | 2011-08-23 14:50:29 +0200 | [diff] [blame] | 1928 | if (rq->cmd_flags & REQ_PRIO) { |
| 1929 | WARN_ON(!cfqq->prio_pending); |
| 1930 | cfqq->prio_pending--; |
Jens Axboe | b53d1ed | 2011-08-19 08:34:48 +0200 | [diff] [blame] | 1931 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1932 | } |
| 1933 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1934 | static int cfq_merge(struct request_queue *q, struct request **req, |
| 1935 | struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1936 | { |
| 1937 | struct cfq_data *cfqd = q->elevator->elevator_data; |
| 1938 | struct request *__rq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1939 | |
Jens Axboe | 206dc69 | 2006-03-28 13:03:44 +0200 | [diff] [blame] | 1940 | __rq = cfq_find_rq_fmerge(cfqd, bio); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 1941 | if (__rq && elv_rq_merge_ok(__rq, bio)) { |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 1942 | *req = __rq; |
| 1943 | return ELEVATOR_FRONT_MERGE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1944 | } |
| 1945 | |
| 1946 | return ELEVATOR_NO_MERGE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1947 | } |
| 1948 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1949 | static void cfq_merged_request(struct request_queue *q, struct request *req, |
Jens Axboe | 21183b0 | 2006-07-13 12:33:14 +0200 | [diff] [blame] | 1950 | int type) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1951 | { |
Jens Axboe | 21183b0 | 2006-07-13 12:33:14 +0200 | [diff] [blame] | 1952 | if (type == ELEVATOR_FRONT_MERGE) { |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1953 | struct cfq_queue *cfqq = RQ_CFQQ(req); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1954 | |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 1955 | cfq_reposition_rq_rb(cfqq, req); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1956 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1957 | } |
| 1958 | |
Divyesh Shah | 812d402 | 2010-04-08 21:14:23 -0700 | [diff] [blame] | 1959 | static void cfq_bio_merged(struct request_queue *q, struct request *req, |
| 1960 | struct bio *bio) |
| 1961 | { |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1962 | cfqg_stats_update_io_merged(RQ_CFQG(req), bio->bi_rw); |
Divyesh Shah | 812d402 | 2010-04-08 21:14:23 -0700 | [diff] [blame] | 1963 | } |
| 1964 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1965 | static void |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1966 | cfq_merged_requests(struct request_queue *q, struct request *rq, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1967 | struct request *next) |
| 1968 | { |
Corrado Zoccolo | cf7c25c | 2009-11-08 17:16:46 +0100 | [diff] [blame] | 1969 | struct cfq_queue *cfqq = RQ_CFQQ(rq); |
Shaohua Li | 4a0b75c | 2011-12-16 14:00:22 +0100 | [diff] [blame] | 1970 | struct cfq_data *cfqd = q->elevator->elevator_data; |
| 1971 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 1972 | /* |
| 1973 | * reposition in fifo if next is older than rq |
| 1974 | */ |
| 1975 | if (!list_empty(&rq->queuelist) && !list_empty(&next->queuelist) && |
Shaohua Li | 3d106fba | 2012-11-06 12:39:51 +0100 | [diff] [blame] | 1976 | time_before(rq_fifo_time(next), rq_fifo_time(rq)) && |
| 1977 | cfqq == RQ_CFQQ(next)) { |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 1978 | list_move(&rq->queuelist, &next->queuelist); |
Jens Axboe | 30996f4 | 2009-10-05 11:03:39 +0200 | [diff] [blame] | 1979 | rq_set_fifo_time(rq, rq_fifo_time(next)); |
| 1980 | } |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 1981 | |
Corrado Zoccolo | cf7c25c | 2009-11-08 17:16:46 +0100 | [diff] [blame] | 1982 | if (cfqq->next_rq == next) |
| 1983 | cfqq->next_rq = rq; |
Jens Axboe | b4878f2 | 2005-10-20 16:42:29 +0200 | [diff] [blame] | 1984 | cfq_remove_request(next); |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 1985 | cfqg_stats_update_io_merged(RQ_CFQG(rq), next->cmd_flags); |
Shaohua Li | 4a0b75c | 2011-12-16 14:00:22 +0100 | [diff] [blame] | 1986 | |
| 1987 | cfqq = RQ_CFQQ(next); |
| 1988 | /* |
| 1989 | * all requests of this queue are merged to other queues, delete it |
| 1990 | * from the service tree. If it's the active_queue, |
| 1991 | * cfq_dispatch_requests() will choose to expire it or do idle |
| 1992 | */ |
| 1993 | if (cfq_cfqq_on_rr(cfqq) && RB_EMPTY_ROOT(&cfqq->sort_list) && |
| 1994 | cfqq != cfqd->active_queue) |
| 1995 | cfq_del_cfqq_rr(cfqd, cfqq); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 1996 | } |
| 1997 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1998 | static int cfq_allow_merge(struct request_queue *q, struct request *rq, |
Jens Axboe | da77526 | 2006-12-20 11:04:12 +0100 | [diff] [blame] | 1999 | struct bio *bio) |
| 2000 | { |
| 2001 | struct cfq_data *cfqd = q->elevator->elevator_data; |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 2002 | struct cfq_io_cq *cic; |
Jens Axboe | da77526 | 2006-12-20 11:04:12 +0100 | [diff] [blame] | 2003 | struct cfq_queue *cfqq; |
Jens Axboe | da77526 | 2006-12-20 11:04:12 +0100 | [diff] [blame] | 2004 | |
| 2005 | /* |
Jens Axboe | ec8acb6 | 2007-01-02 18:32:11 +0100 | [diff] [blame] | 2006 | * Disallow merge of a sync bio into an async request. |
Jens Axboe | da77526 | 2006-12-20 11:04:12 +0100 | [diff] [blame] | 2007 | */ |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 2008 | if (cfq_bio_sync(bio) && !rq_is_sync(rq)) |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 2009 | return false; |
Jens Axboe | da77526 | 2006-12-20 11:04:12 +0100 | [diff] [blame] | 2010 | |
| 2011 | /* |
Tejun Heo | f1a4f4d | 2011-12-14 00:33:39 +0100 | [diff] [blame] | 2012 | * Lookup the cfqq that this bio will be queued with and allow |
Tejun Heo | 07c2bd3 | 2012-02-08 09:19:42 +0100 | [diff] [blame] | 2013 | * merge only if rq is queued there. |
Jens Axboe | da77526 | 2006-12-20 11:04:12 +0100 | [diff] [blame] | 2014 | */ |
Tejun Heo | 07c2bd3 | 2012-02-08 09:19:42 +0100 | [diff] [blame] | 2015 | cic = cfq_cic_lookup(cfqd, current->io_context); |
| 2016 | if (!cic) |
| 2017 | return false; |
Jens Axboe | 719d340 | 2006-12-22 09:38:53 +0100 | [diff] [blame] | 2018 | |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 2019 | cfqq = cic_to_cfqq(cic, cfq_bio_sync(bio)); |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 2020 | return cfqq == RQ_CFQQ(rq); |
Jens Axboe | da77526 | 2006-12-20 11:04:12 +0100 | [diff] [blame] | 2021 | } |
| 2022 | |
Divyesh Shah | 812df48 | 2010-04-08 21:15:35 -0700 | [diff] [blame] | 2023 | static inline void cfq_del_timer(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
| 2024 | { |
| 2025 | del_timer(&cfqd->idle_slice_timer); |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 2026 | cfqg_stats_update_idle_time(cfqq->cfqg); |
Divyesh Shah | 812df48 | 2010-04-08 21:15:35 -0700 | [diff] [blame] | 2027 | } |
| 2028 | |
Jens Axboe | febffd6 | 2008-01-28 13:19:43 +0100 | [diff] [blame] | 2029 | static void __cfq_set_active_queue(struct cfq_data *cfqd, |
| 2030 | struct cfq_queue *cfqq) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2031 | { |
| 2032 | if (cfqq) { |
Divyesh Shah | b1ffe73 | 2010-03-25 15:45:03 +0100 | [diff] [blame] | 2033 | cfq_log_cfqq(cfqd, cfqq, "set_active wl_prio:%d wl_type:%d", |
| 2034 | cfqd->serving_prio, cfqd->serving_type); |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 2035 | cfqg_stats_update_avg_queue_size(cfqq->cfqg); |
Justin TerAvest | 62a37f6 | 2011-03-23 08:25:44 +0100 | [diff] [blame] | 2036 | cfqq->slice_start = 0; |
| 2037 | cfqq->dispatch_start = jiffies; |
| 2038 | cfqq->allocated_slice = 0; |
| 2039 | cfqq->slice_end = 0; |
| 2040 | cfqq->slice_dispatch = 0; |
| 2041 | cfqq->nr_sectors = 0; |
| 2042 | |
| 2043 | cfq_clear_cfqq_wait_request(cfqq); |
| 2044 | cfq_clear_cfqq_must_dispatch(cfqq); |
| 2045 | cfq_clear_cfqq_must_alloc_slice(cfqq); |
| 2046 | cfq_clear_cfqq_fifo_expire(cfqq); |
| 2047 | cfq_mark_cfqq_slice_new(cfqq); |
| 2048 | |
| 2049 | cfq_del_timer(cfqd, cfqq); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2050 | } |
| 2051 | |
| 2052 | cfqd->active_queue = cfqq; |
| 2053 | } |
| 2054 | |
| 2055 | /* |
Jens Axboe | 7b14e3b | 2006-02-28 09:35:11 +0100 | [diff] [blame] | 2056 | * current cfqq expired its slice (or was too idle), select new one |
| 2057 | */ |
| 2058 | static void |
| 2059 | __cfq_slice_expired(struct cfq_data *cfqd, struct cfq_queue *cfqq, |
Vivek Goyal | e5ff082 | 2010-04-26 19:25:11 +0200 | [diff] [blame] | 2060 | bool timed_out) |
Jens Axboe | 7b14e3b | 2006-02-28 09:35:11 +0100 | [diff] [blame] | 2061 | { |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 2062 | cfq_log_cfqq(cfqd, cfqq, "slice expired t=%d", timed_out); |
| 2063 | |
Jens Axboe | 7b14e3b | 2006-02-28 09:35:11 +0100 | [diff] [blame] | 2064 | if (cfq_cfqq_wait_request(cfqq)) |
Divyesh Shah | 812df48 | 2010-04-08 21:15:35 -0700 | [diff] [blame] | 2065 | cfq_del_timer(cfqd, cfqq); |
Jens Axboe | 7b14e3b | 2006-02-28 09:35:11 +0100 | [diff] [blame] | 2066 | |
Jens Axboe | 7b14e3b | 2006-02-28 09:35:11 +0100 | [diff] [blame] | 2067 | cfq_clear_cfqq_wait_request(cfqq); |
Vivek Goyal | f75edf2 | 2009-12-03 12:59:53 -0500 | [diff] [blame] | 2068 | cfq_clear_cfqq_wait_busy(cfqq); |
Jens Axboe | 7b14e3b | 2006-02-28 09:35:11 +0100 | [diff] [blame] | 2069 | |
| 2070 | /* |
Shaohua Li | ae54abe | 2010-02-05 13:11:45 +0100 | [diff] [blame] | 2071 | * If this cfqq is shared between multiple processes, check to |
| 2072 | * make sure that those processes are still issuing I/Os within |
| 2073 | * the mean seek distance. If not, it may be time to break the |
| 2074 | * queues apart again. |
| 2075 | */ |
| 2076 | if (cfq_cfqq_coop(cfqq) && CFQQ_SEEKY(cfqq)) |
| 2077 | cfq_mark_cfqq_split_coop(cfqq); |
| 2078 | |
| 2079 | /* |
Jens Axboe | 6084cdd | 2007-04-23 08:25:00 +0200 | [diff] [blame] | 2080 | * store what was left of this slice, if the queue idled/timed out |
Jens Axboe | 7b14e3b | 2006-02-28 09:35:11 +0100 | [diff] [blame] | 2081 | */ |
Shaohua Li | c553f8e | 2011-01-14 08:41:03 +0100 | [diff] [blame] | 2082 | if (timed_out) { |
| 2083 | if (cfq_cfqq_slice_new(cfqq)) |
Vivek Goyal | ba5bd52 | 2011-01-19 08:25:02 -0700 | [diff] [blame] | 2084 | cfqq->slice_resid = cfq_scaled_cfqq_slice(cfqd, cfqq); |
Shaohua Li | c553f8e | 2011-01-14 08:41:03 +0100 | [diff] [blame] | 2085 | else |
| 2086 | cfqq->slice_resid = cfqq->slice_end - jiffies; |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 2087 | cfq_log_cfqq(cfqd, cfqq, "resid=%ld", cfqq->slice_resid); |
| 2088 | } |
Jens Axboe | 7b14e3b | 2006-02-28 09:35:11 +0100 | [diff] [blame] | 2089 | |
Vivek Goyal | e5ff082 | 2010-04-26 19:25:11 +0200 | [diff] [blame] | 2090 | cfq_group_served(cfqd, cfqq->cfqg, cfqq); |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 2091 | |
Vivek Goyal | f04a642 | 2009-12-03 12:59:40 -0500 | [diff] [blame] | 2092 | if (cfq_cfqq_on_rr(cfqq) && RB_EMPTY_ROOT(&cfqq->sort_list)) |
| 2093 | cfq_del_cfqq_rr(cfqd, cfqq); |
| 2094 | |
Jens Axboe | edd75ff | 2007-04-19 12:03:34 +0200 | [diff] [blame] | 2095 | cfq_resort_rr_list(cfqd, cfqq); |
Jens Axboe | 7b14e3b | 2006-02-28 09:35:11 +0100 | [diff] [blame] | 2096 | |
| 2097 | if (cfqq == cfqd->active_queue) |
| 2098 | cfqd->active_queue = NULL; |
| 2099 | |
| 2100 | if (cfqd->active_cic) { |
Tejun Heo | 11a3122 | 2012-02-07 07:51:30 +0100 | [diff] [blame] | 2101 | put_io_context(cfqd->active_cic->icq.ioc); |
Jens Axboe | 7b14e3b | 2006-02-28 09:35:11 +0100 | [diff] [blame] | 2102 | cfqd->active_cic = NULL; |
| 2103 | } |
Jens Axboe | 7b14e3b | 2006-02-28 09:35:11 +0100 | [diff] [blame] | 2104 | } |
| 2105 | |
Vivek Goyal | e5ff082 | 2010-04-26 19:25:11 +0200 | [diff] [blame] | 2106 | static inline void cfq_slice_expired(struct cfq_data *cfqd, bool timed_out) |
Jens Axboe | 7b14e3b | 2006-02-28 09:35:11 +0100 | [diff] [blame] | 2107 | { |
| 2108 | struct cfq_queue *cfqq = cfqd->active_queue; |
| 2109 | |
| 2110 | if (cfqq) |
Vivek Goyal | e5ff082 | 2010-04-26 19:25:11 +0200 | [diff] [blame] | 2111 | __cfq_slice_expired(cfqd, cfqq, timed_out); |
Jens Axboe | 7b14e3b | 2006-02-28 09:35:11 +0100 | [diff] [blame] | 2112 | } |
| 2113 | |
Jens Axboe | 498d3aa2 | 2007-04-26 12:54:48 +0200 | [diff] [blame] | 2114 | /* |
| 2115 | * Get next queue for service. Unless we have a queue preemption, |
| 2116 | * we'll simply select the first cfqq in the service tree. |
| 2117 | */ |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2118 | static struct cfq_queue *cfq_get_next_queue(struct cfq_data *cfqd) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2119 | { |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 2120 | struct cfq_rb_root *service_tree = |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 2121 | service_tree_for(cfqd->serving_group, cfqd->serving_prio, |
Vivek Goyal | 65b32a5 | 2009-12-16 17:52:59 -0500 | [diff] [blame] | 2122 | cfqd->serving_type); |
Jens Axboe | edd75ff | 2007-04-19 12:03:34 +0200 | [diff] [blame] | 2123 | |
Vivek Goyal | f04a642 | 2009-12-03 12:59:40 -0500 | [diff] [blame] | 2124 | if (!cfqd->rq_queued) |
| 2125 | return NULL; |
| 2126 | |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 2127 | /* There is nothing to dispatch */ |
| 2128 | if (!service_tree) |
| 2129 | return NULL; |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 2130 | if (RB_EMPTY_ROOT(&service_tree->rb)) |
| 2131 | return NULL; |
| 2132 | return cfq_rb_first(service_tree); |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2133 | } |
| 2134 | |
Vivek Goyal | f04a642 | 2009-12-03 12:59:40 -0500 | [diff] [blame] | 2135 | static struct cfq_queue *cfq_get_next_queue_forced(struct cfq_data *cfqd) |
| 2136 | { |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 2137 | struct cfq_group *cfqg; |
Vivek Goyal | f04a642 | 2009-12-03 12:59:40 -0500 | [diff] [blame] | 2138 | struct cfq_queue *cfqq; |
| 2139 | int i, j; |
| 2140 | struct cfq_rb_root *st; |
| 2141 | |
| 2142 | if (!cfqd->rq_queued) |
| 2143 | return NULL; |
| 2144 | |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 2145 | cfqg = cfq_get_next_cfqg(cfqd); |
| 2146 | if (!cfqg) |
| 2147 | return NULL; |
| 2148 | |
Vivek Goyal | f04a642 | 2009-12-03 12:59:40 -0500 | [diff] [blame] | 2149 | for_each_cfqg_st(cfqg, i, j, st) |
| 2150 | if ((cfqq = cfq_rb_first(st)) != NULL) |
| 2151 | return cfqq; |
| 2152 | return NULL; |
| 2153 | } |
| 2154 | |
Jens Axboe | 498d3aa2 | 2007-04-26 12:54:48 +0200 | [diff] [blame] | 2155 | /* |
| 2156 | * Get and set a new active queue for service. |
| 2157 | */ |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2158 | static struct cfq_queue *cfq_set_active_queue(struct cfq_data *cfqd, |
| 2159 | struct cfq_queue *cfqq) |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2160 | { |
Jens Axboe | e00ef79 | 2009-11-04 08:54:55 +0100 | [diff] [blame] | 2161 | if (!cfqq) |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2162 | cfqq = cfq_get_next_queue(cfqd); |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2163 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2164 | __cfq_set_active_queue(cfqd, cfqq); |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 2165 | return cfqq; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2166 | } |
| 2167 | |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 2168 | static inline sector_t cfq_dist_from_last(struct cfq_data *cfqd, |
| 2169 | struct request *rq) |
| 2170 | { |
Tejun Heo | 83096eb | 2009-05-07 22:24:39 +0900 | [diff] [blame] | 2171 | if (blk_rq_pos(rq) >= cfqd->last_position) |
| 2172 | return blk_rq_pos(rq) - cfqd->last_position; |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 2173 | else |
Tejun Heo | 83096eb | 2009-05-07 22:24:39 +0900 | [diff] [blame] | 2174 | return cfqd->last_position - blk_rq_pos(rq); |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 2175 | } |
| 2176 | |
Jeff Moyer | b2c18e1 | 2009-10-23 17:14:49 -0400 | [diff] [blame] | 2177 | static inline int cfq_rq_close(struct cfq_data *cfqd, struct cfq_queue *cfqq, |
Shaohua Li | e9ce335 | 2010-03-19 08:03:04 +0100 | [diff] [blame] | 2178 | struct request *rq) |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2179 | { |
Shaohua Li | e9ce335 | 2010-03-19 08:03:04 +0100 | [diff] [blame] | 2180 | return cfq_dist_from_last(cfqd, rq) <= CFQQ_CLOSE_THR; |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2181 | } |
| 2182 | |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2183 | static struct cfq_queue *cfqq_close(struct cfq_data *cfqd, |
| 2184 | struct cfq_queue *cur_cfqq) |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2185 | { |
Jens Axboe | f2d1f0a | 2009-04-23 12:19:38 +0200 | [diff] [blame] | 2186 | struct rb_root *root = &cfqd->prio_trees[cur_cfqq->org_ioprio]; |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2187 | struct rb_node *parent, *node; |
| 2188 | struct cfq_queue *__cfqq; |
| 2189 | sector_t sector = cfqd->last_position; |
| 2190 | |
| 2191 | if (RB_EMPTY_ROOT(root)) |
| 2192 | return NULL; |
| 2193 | |
| 2194 | /* |
| 2195 | * First, if we find a request starting at the end of the last |
| 2196 | * request, choose it. |
| 2197 | */ |
Jens Axboe | f2d1f0a | 2009-04-23 12:19:38 +0200 | [diff] [blame] | 2198 | __cfqq = cfq_prio_tree_lookup(cfqd, root, sector, &parent, NULL); |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2199 | if (__cfqq) |
| 2200 | return __cfqq; |
| 2201 | |
| 2202 | /* |
| 2203 | * If the exact sector wasn't found, the parent of the NULL leaf |
| 2204 | * will contain the closest sector. |
| 2205 | */ |
| 2206 | __cfqq = rb_entry(parent, struct cfq_queue, p_node); |
Shaohua Li | e9ce335 | 2010-03-19 08:03:04 +0100 | [diff] [blame] | 2207 | if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq)) |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2208 | return __cfqq; |
| 2209 | |
Tejun Heo | 2e46e8b | 2009-05-07 22:24:41 +0900 | [diff] [blame] | 2210 | if (blk_rq_pos(__cfqq->next_rq) < sector) |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2211 | node = rb_next(&__cfqq->p_node); |
| 2212 | else |
| 2213 | node = rb_prev(&__cfqq->p_node); |
| 2214 | if (!node) |
| 2215 | return NULL; |
| 2216 | |
| 2217 | __cfqq = rb_entry(node, struct cfq_queue, p_node); |
Shaohua Li | e9ce335 | 2010-03-19 08:03:04 +0100 | [diff] [blame] | 2218 | if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq)) |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2219 | return __cfqq; |
| 2220 | |
| 2221 | return NULL; |
| 2222 | } |
| 2223 | |
| 2224 | /* |
| 2225 | * cfqd - obvious |
| 2226 | * cur_cfqq - passed in so that we don't decide that the current queue is |
| 2227 | * closely cooperating with itself. |
| 2228 | * |
| 2229 | * So, basically we're assuming that that cur_cfqq has dispatched at least |
| 2230 | * one request, and that cfqd->last_position reflects a position on the disk |
| 2231 | * associated with the I/O issued by cur_cfqq. I'm not sure this is a valid |
| 2232 | * assumption. |
| 2233 | */ |
| 2234 | static struct cfq_queue *cfq_close_cooperator(struct cfq_data *cfqd, |
Jeff Moyer | b3b6d04 | 2009-10-23 17:14:51 -0400 | [diff] [blame] | 2235 | struct cfq_queue *cur_cfqq) |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2236 | { |
| 2237 | struct cfq_queue *cfqq; |
| 2238 | |
Divyesh Shah | 39c01b2 | 2010-03-25 15:45:57 +0100 | [diff] [blame] | 2239 | if (cfq_class_idle(cur_cfqq)) |
| 2240 | return NULL; |
Jeff Moyer | e6c5bc7 | 2009-10-23 17:14:52 -0400 | [diff] [blame] | 2241 | if (!cfq_cfqq_sync(cur_cfqq)) |
| 2242 | return NULL; |
| 2243 | if (CFQQ_SEEKY(cur_cfqq)) |
| 2244 | return NULL; |
| 2245 | |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2246 | /* |
Gui Jianfeng | b9d8f4c | 2009-12-08 08:54:17 +0100 | [diff] [blame] | 2247 | * Don't search priority tree if it's the only queue in the group. |
| 2248 | */ |
| 2249 | if (cur_cfqq->cfqg->nr_cfqq == 1) |
| 2250 | return NULL; |
| 2251 | |
| 2252 | /* |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 2253 | * We should notice if some of the queues are cooperating, eg |
| 2254 | * working closely on the same area of the disk. In that case, |
| 2255 | * we can group them together and don't waste time idling. |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2256 | */ |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2257 | cfqq = cfqq_close(cfqd, cur_cfqq); |
| 2258 | if (!cfqq) |
| 2259 | return NULL; |
| 2260 | |
Vivek Goyal | 8682e1f | 2009-12-03 12:59:50 -0500 | [diff] [blame] | 2261 | /* If new queue belongs to different cfq_group, don't choose it */ |
| 2262 | if (cur_cfqq->cfqg != cfqq->cfqg) |
| 2263 | return NULL; |
| 2264 | |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 2265 | /* |
| 2266 | * It only makes sense to merge sync queues. |
| 2267 | */ |
| 2268 | if (!cfq_cfqq_sync(cfqq)) |
| 2269 | return NULL; |
Jeff Moyer | e6c5bc7 | 2009-10-23 17:14:52 -0400 | [diff] [blame] | 2270 | if (CFQQ_SEEKY(cfqq)) |
| 2271 | return NULL; |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 2272 | |
Corrado Zoccolo | c0324a0 | 2009-10-27 19:16:03 +0100 | [diff] [blame] | 2273 | /* |
| 2274 | * Do not merge queues of different priority classes |
| 2275 | */ |
| 2276 | if (cfq_class_rt(cfqq) != cfq_class_rt(cur_cfqq)) |
| 2277 | return NULL; |
| 2278 | |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2279 | return cfqq; |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2280 | } |
| 2281 | |
Corrado Zoccolo | a6d44e9 | 2009-10-26 22:45:11 +0100 | [diff] [blame] | 2282 | /* |
| 2283 | * Determine whether we should enforce idle window for this queue. |
| 2284 | */ |
| 2285 | |
| 2286 | static bool cfq_should_idle(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
| 2287 | { |
| 2288 | enum wl_prio_t prio = cfqq_prio(cfqq); |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2289 | struct cfq_rb_root *service_tree = cfqq->service_tree; |
Corrado Zoccolo | a6d44e9 | 2009-10-26 22:45:11 +0100 | [diff] [blame] | 2290 | |
Vivek Goyal | f04a642 | 2009-12-03 12:59:40 -0500 | [diff] [blame] | 2291 | BUG_ON(!service_tree); |
| 2292 | BUG_ON(!service_tree->count); |
| 2293 | |
Vivek Goyal | b6508c1 | 2010-08-23 12:23:33 +0200 | [diff] [blame] | 2294 | if (!cfqd->cfq_slice_idle) |
| 2295 | return false; |
| 2296 | |
Corrado Zoccolo | a6d44e9 | 2009-10-26 22:45:11 +0100 | [diff] [blame] | 2297 | /* We never do for idle class queues. */ |
| 2298 | if (prio == IDLE_WORKLOAD) |
| 2299 | return false; |
| 2300 | |
| 2301 | /* We do for queues that were marked with idle window flag. */ |
Shaohua Li | 3c764b7 | 2009-12-04 13:12:06 +0100 | [diff] [blame] | 2302 | if (cfq_cfqq_idle_window(cfqq) && |
| 2303 | !(blk_queue_nonrot(cfqd->queue) && cfqd->hw_tag)) |
Corrado Zoccolo | a6d44e9 | 2009-10-26 22:45:11 +0100 | [diff] [blame] | 2304 | return true; |
| 2305 | |
| 2306 | /* |
| 2307 | * Otherwise, we do only if they are the last ones |
| 2308 | * in their service tree. |
| 2309 | */ |
Shaohua Li | f5f2b6c | 2011-07-12 14:24:55 +0200 | [diff] [blame] | 2310 | if (service_tree->count == 1 && cfq_cfqq_sync(cfqq) && |
| 2311 | !cfq_io_thinktime_big(cfqd, &service_tree->ttime, false)) |
Shaohua Li | c1e4475 | 2010-11-08 15:01:02 +0100 | [diff] [blame] | 2312 | return true; |
Divyesh Shah | b1ffe73 | 2010-03-25 15:45:03 +0100 | [diff] [blame] | 2313 | cfq_log_cfqq(cfqd, cfqq, "Not idling. st->count:%d", |
| 2314 | service_tree->count); |
Shaohua Li | c1e4475 | 2010-11-08 15:01:02 +0100 | [diff] [blame] | 2315 | return false; |
Corrado Zoccolo | a6d44e9 | 2009-10-26 22:45:11 +0100 | [diff] [blame] | 2316 | } |
| 2317 | |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2318 | static void cfq_arm_slice_timer(struct cfq_data *cfqd) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2319 | { |
Jens Axboe | 1792669 | 2007-01-19 11:59:30 +1100 | [diff] [blame] | 2320 | struct cfq_queue *cfqq = cfqd->active_queue; |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 2321 | struct cfq_io_cq *cic; |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 2322 | unsigned long sl, group_idle = 0; |
Jens Axboe | 7b14e3b | 2006-02-28 09:35:11 +0100 | [diff] [blame] | 2323 | |
Jens Axboe | a68bbddba | 2008-09-24 13:03:33 +0200 | [diff] [blame] | 2324 | /* |
Jens Axboe | f7d7b7a | 2008-09-25 11:37:50 +0200 | [diff] [blame] | 2325 | * SSD device without seek penalty, disable idling. But only do so |
| 2326 | * for devices that support queuing, otherwise we still have a problem |
| 2327 | * with sync vs async workloads. |
Jens Axboe | a68bbddba | 2008-09-24 13:03:33 +0200 | [diff] [blame] | 2328 | */ |
Jens Axboe | f7d7b7a | 2008-09-25 11:37:50 +0200 | [diff] [blame] | 2329 | if (blk_queue_nonrot(cfqd->queue) && cfqd->hw_tag) |
Jens Axboe | a68bbddba | 2008-09-24 13:03:33 +0200 | [diff] [blame] | 2330 | return; |
| 2331 | |
Jens Axboe | dd67d05 | 2006-06-21 09:36:18 +0200 | [diff] [blame] | 2332 | WARN_ON(!RB_EMPTY_ROOT(&cfqq->sort_list)); |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2333 | WARN_ON(cfq_cfqq_slice_new(cfqq)); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2334 | |
| 2335 | /* |
| 2336 | * idle is disabled, either manually or by past process history |
| 2337 | */ |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 2338 | if (!cfq_should_idle(cfqd, cfqq)) { |
| 2339 | /* no queue idling. Check for group idling */ |
| 2340 | if (cfqd->cfq_group_idle) |
| 2341 | group_idle = cfqd->cfq_group_idle; |
| 2342 | else |
| 2343 | return; |
| 2344 | } |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2345 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2346 | /* |
Corrado Zoccolo | 8e55063 | 2009-11-26 10:02:58 +0100 | [diff] [blame] | 2347 | * still active requests from this queue, don't idle |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 2348 | */ |
Corrado Zoccolo | 8e55063 | 2009-11-26 10:02:58 +0100 | [diff] [blame] | 2349 | if (cfqq->dispatched) |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 2350 | return; |
| 2351 | |
| 2352 | /* |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2353 | * task has exited, don't wait |
| 2354 | */ |
Jens Axboe | 206dc69 | 2006-03-28 13:03:44 +0200 | [diff] [blame] | 2355 | cic = cfqd->active_cic; |
Tejun Heo | f6e8d01 | 2012-03-05 13:15:26 -0800 | [diff] [blame] | 2356 | if (!cic || !atomic_read(&cic->icq.ioc->active_ref)) |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2357 | return; |
| 2358 | |
Corrado Zoccolo | 355b659 | 2009-10-08 08:43:32 +0200 | [diff] [blame] | 2359 | /* |
| 2360 | * If our average think time is larger than the remaining time |
| 2361 | * slice, then don't idle. This avoids overrunning the allotted |
| 2362 | * time slice. |
| 2363 | */ |
Shaohua Li | 383cd72 | 2011-07-12 14:24:35 +0200 | [diff] [blame] | 2364 | if (sample_valid(cic->ttime.ttime_samples) && |
| 2365 | (cfqq->slice_end - jiffies < cic->ttime.ttime_mean)) { |
Joe Perches | fd16d26 | 2011-06-13 10:42:49 +0200 | [diff] [blame] | 2366 | cfq_log_cfqq(cfqd, cfqq, "Not idling. think_time:%lu", |
Shaohua Li | 383cd72 | 2011-07-12 14:24:35 +0200 | [diff] [blame] | 2367 | cic->ttime.ttime_mean); |
Corrado Zoccolo | 355b659 | 2009-10-08 08:43:32 +0200 | [diff] [blame] | 2368 | return; |
Divyesh Shah | b1ffe73 | 2010-03-25 15:45:03 +0100 | [diff] [blame] | 2369 | } |
Corrado Zoccolo | 355b659 | 2009-10-08 08:43:32 +0200 | [diff] [blame] | 2370 | |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 2371 | /* There are other queues in the group, don't do group idle */ |
| 2372 | if (group_idle && cfqq->cfqg->nr_cfqq > 1) |
| 2373 | return; |
| 2374 | |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 2375 | cfq_mark_cfqq_wait_request(cfqq); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2376 | |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 2377 | if (group_idle) |
| 2378 | sl = cfqd->cfq_group_idle; |
| 2379 | else |
| 2380 | sl = cfqd->cfq_slice_idle; |
Jens Axboe | 206dc69 | 2006-03-28 13:03:44 +0200 | [diff] [blame] | 2381 | |
Jens Axboe | 7b14e3b | 2006-02-28 09:35:11 +0100 | [diff] [blame] | 2382 | mod_timer(&cfqd->idle_slice_timer, jiffies + sl); |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 2383 | cfqg_stats_set_start_idle_time(cfqq->cfqg); |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 2384 | cfq_log_cfqq(cfqd, cfqq, "arm_idle: %lu group_idle: %d", sl, |
| 2385 | group_idle ? 1 : 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2386 | } |
| 2387 | |
Jens Axboe | 498d3aa2 | 2007-04-26 12:54:48 +0200 | [diff] [blame] | 2388 | /* |
| 2389 | * Move request from internal lists to the request queue dispatch list. |
| 2390 | */ |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 2391 | static void cfq_dispatch_insert(struct request_queue *q, struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2392 | { |
Jens Axboe | 3ed9a29 | 2007-04-23 08:33:33 +0200 | [diff] [blame] | 2393 | struct cfq_data *cfqd = q->elevator->elevator_data; |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 2394 | struct cfq_queue *cfqq = RQ_CFQQ(rq); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2395 | |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 2396 | cfq_log_cfqq(cfqd, cfqq, "dispatch_insert"); |
| 2397 | |
Jeff Moyer | 06d2188 | 2009-09-11 17:08:59 +0200 | [diff] [blame] | 2398 | cfqq->next_rq = cfq_find_next_rq(cfqd, cfqq, rq); |
Jens Axboe | 5380a10 | 2006-07-13 12:37:56 +0200 | [diff] [blame] | 2399 | cfq_remove_request(rq); |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2400 | cfqq->dispatched++; |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 2401 | (RQ_CFQG(rq))->dispatched++; |
Jens Axboe | 5380a10 | 2006-07-13 12:37:56 +0200 | [diff] [blame] | 2402 | elv_dispatch_sort(q, rq); |
Jens Axboe | 3ed9a29 | 2007-04-23 08:33:33 +0200 | [diff] [blame] | 2403 | |
Corrado Zoccolo | 53c583d | 2010-02-28 19:45:05 +0100 | [diff] [blame] | 2404 | cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]++; |
Vivek Goyal | c4e7893 | 2010-08-23 12:25:03 +0200 | [diff] [blame] | 2405 | cfqq->nr_sectors += blk_rq_sectors(rq); |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 2406 | cfqg_stats_update_dispatch(cfqq->cfqg, blk_rq_bytes(rq), rq->cmd_flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2407 | } |
| 2408 | |
| 2409 | /* |
| 2410 | * return expired entry, or NULL to just start from scratch in rbtree |
| 2411 | */ |
Jens Axboe | febffd6 | 2008-01-28 13:19:43 +0100 | [diff] [blame] | 2412 | static struct request *cfq_check_fifo(struct cfq_queue *cfqq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2413 | { |
Jens Axboe | 30996f4 | 2009-10-05 11:03:39 +0200 | [diff] [blame] | 2414 | struct request *rq = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2415 | |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 2416 | if (cfq_cfqq_fifo_expire(cfqq)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2417 | return NULL; |
Jens Axboe | cb88741 | 2007-01-19 12:01:16 +1100 | [diff] [blame] | 2418 | |
| 2419 | cfq_mark_cfqq_fifo_expire(cfqq); |
| 2420 | |
Jens Axboe | 89850f7 | 2006-07-22 16:48:31 +0200 | [diff] [blame] | 2421 | if (list_empty(&cfqq->fifo)) |
| 2422 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2423 | |
Jens Axboe | 89850f7 | 2006-07-22 16:48:31 +0200 | [diff] [blame] | 2424 | rq = rq_entry_fifo(cfqq->fifo.next); |
Jens Axboe | 30996f4 | 2009-10-05 11:03:39 +0200 | [diff] [blame] | 2425 | if (time_before(jiffies, rq_fifo_time(rq))) |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 2426 | rq = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2427 | |
Jens Axboe | 30996f4 | 2009-10-05 11:03:39 +0200 | [diff] [blame] | 2428 | cfq_log_cfqq(cfqq->cfqd, cfqq, "fifo=%p", rq); |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2429 | return rq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2430 | } |
| 2431 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2432 | static inline int |
| 2433 | cfq_prio_to_maxrq(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
| 2434 | { |
| 2435 | const int base_rq = cfqd->cfq_slice_async_rq; |
| 2436 | |
| 2437 | WARN_ON(cfqq->ioprio >= IOPRIO_BE_NR); |
| 2438 | |
Namhyung Kim | b9f8ce0 | 2011-05-24 10:23:21 +0200 | [diff] [blame] | 2439 | return 2 * base_rq * (IOPRIO_BE_NR - cfqq->ioprio); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2440 | } |
| 2441 | |
| 2442 | /* |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 2443 | * Must be called with the queue_lock held. |
| 2444 | */ |
| 2445 | static int cfqq_process_refs(struct cfq_queue *cfqq) |
| 2446 | { |
| 2447 | int process_refs, io_refs; |
| 2448 | |
| 2449 | io_refs = cfqq->allocated[READ] + cfqq->allocated[WRITE]; |
Shaohua Li | 30d7b94 | 2011-01-07 08:46:59 +0100 | [diff] [blame] | 2450 | process_refs = cfqq->ref - io_refs; |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 2451 | BUG_ON(process_refs < 0); |
| 2452 | return process_refs; |
| 2453 | } |
| 2454 | |
| 2455 | static void cfq_setup_merge(struct cfq_queue *cfqq, struct cfq_queue *new_cfqq) |
| 2456 | { |
Jeff Moyer | e6c5bc7 | 2009-10-23 17:14:52 -0400 | [diff] [blame] | 2457 | int process_refs, new_process_refs; |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 2458 | struct cfq_queue *__cfqq; |
| 2459 | |
Jeff Moyer | c10b61f | 2010-06-17 10:19:11 -0400 | [diff] [blame] | 2460 | /* |
| 2461 | * If there are no process references on the new_cfqq, then it is |
| 2462 | * unsafe to follow the ->new_cfqq chain as other cfqq's in the |
| 2463 | * chain may have dropped their last reference (not just their |
| 2464 | * last process reference). |
| 2465 | */ |
| 2466 | if (!cfqq_process_refs(new_cfqq)) |
| 2467 | return; |
| 2468 | |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 2469 | /* Avoid a circular list and skip interim queue merges */ |
| 2470 | while ((__cfqq = new_cfqq->new_cfqq)) { |
| 2471 | if (__cfqq == cfqq) |
| 2472 | return; |
| 2473 | new_cfqq = __cfqq; |
| 2474 | } |
| 2475 | |
| 2476 | process_refs = cfqq_process_refs(cfqq); |
Jeff Moyer | c10b61f | 2010-06-17 10:19:11 -0400 | [diff] [blame] | 2477 | new_process_refs = cfqq_process_refs(new_cfqq); |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 2478 | /* |
| 2479 | * If the process for the cfqq has gone away, there is no |
| 2480 | * sense in merging the queues. |
| 2481 | */ |
Jeff Moyer | c10b61f | 2010-06-17 10:19:11 -0400 | [diff] [blame] | 2482 | if (process_refs == 0 || new_process_refs == 0) |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 2483 | return; |
| 2484 | |
Jeff Moyer | e6c5bc7 | 2009-10-23 17:14:52 -0400 | [diff] [blame] | 2485 | /* |
| 2486 | * Merge in the direction of the lesser amount of work. |
| 2487 | */ |
Jeff Moyer | e6c5bc7 | 2009-10-23 17:14:52 -0400 | [diff] [blame] | 2488 | if (new_process_refs >= process_refs) { |
| 2489 | cfqq->new_cfqq = new_cfqq; |
Shaohua Li | 30d7b94 | 2011-01-07 08:46:59 +0100 | [diff] [blame] | 2490 | new_cfqq->ref += process_refs; |
Jeff Moyer | e6c5bc7 | 2009-10-23 17:14:52 -0400 | [diff] [blame] | 2491 | } else { |
| 2492 | new_cfqq->new_cfqq = cfqq; |
Shaohua Li | 30d7b94 | 2011-01-07 08:46:59 +0100 | [diff] [blame] | 2493 | cfqq->ref += new_process_refs; |
Jeff Moyer | e6c5bc7 | 2009-10-23 17:14:52 -0400 | [diff] [blame] | 2494 | } |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 2495 | } |
| 2496 | |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 2497 | static enum wl_type_t cfq_choose_wl(struct cfq_data *cfqd, |
Vivek Goyal | 65b32a5 | 2009-12-16 17:52:59 -0500 | [diff] [blame] | 2498 | struct cfq_group *cfqg, enum wl_prio_t prio) |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2499 | { |
| 2500 | struct cfq_queue *queue; |
| 2501 | int i; |
| 2502 | bool key_valid = false; |
| 2503 | unsigned long lowest_key = 0; |
| 2504 | enum wl_type_t cur_best = SYNC_NOIDLE_WORKLOAD; |
| 2505 | |
Vivek Goyal | 65b32a5 | 2009-12-16 17:52:59 -0500 | [diff] [blame] | 2506 | for (i = 0; i <= SYNC_WORKLOAD; ++i) { |
| 2507 | /* select the one with lowest rb_key */ |
| 2508 | queue = cfq_rb_first(service_tree_for(cfqg, prio, i)); |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2509 | if (queue && |
| 2510 | (!key_valid || time_before(queue->rb_key, lowest_key))) { |
| 2511 | lowest_key = queue->rb_key; |
| 2512 | cur_best = i; |
| 2513 | key_valid = true; |
| 2514 | } |
| 2515 | } |
| 2516 | |
| 2517 | return cur_best; |
| 2518 | } |
| 2519 | |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 2520 | static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg) |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2521 | { |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2522 | unsigned slice; |
| 2523 | unsigned count; |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 2524 | struct cfq_rb_root *st; |
Vivek Goyal | 58ff82f | 2009-12-03 12:59:44 -0500 | [diff] [blame] | 2525 | unsigned group_slice; |
Shaohua Li writes | e4ea0c1 | 2010-12-13 14:32:22 +0100 | [diff] [blame] | 2526 | enum wl_prio_t original_prio = cfqd->serving_prio; |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 2527 | |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2528 | /* Choose next priority. RT > BE > IDLE */ |
Vivek Goyal | 58ff82f | 2009-12-03 12:59:44 -0500 | [diff] [blame] | 2529 | if (cfq_group_busy_queues_wl(RT_WORKLOAD, cfqd, cfqg)) |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2530 | cfqd->serving_prio = RT_WORKLOAD; |
Vivek Goyal | 58ff82f | 2009-12-03 12:59:44 -0500 | [diff] [blame] | 2531 | else if (cfq_group_busy_queues_wl(BE_WORKLOAD, cfqd, cfqg)) |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2532 | cfqd->serving_prio = BE_WORKLOAD; |
| 2533 | else { |
| 2534 | cfqd->serving_prio = IDLE_WORKLOAD; |
| 2535 | cfqd->workload_expires = jiffies + 1; |
| 2536 | return; |
| 2537 | } |
| 2538 | |
Shaohua Li writes | e4ea0c1 | 2010-12-13 14:32:22 +0100 | [diff] [blame] | 2539 | if (original_prio != cfqd->serving_prio) |
| 2540 | goto new_workload; |
| 2541 | |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2542 | /* |
| 2543 | * For RT and BE, we have to choose also the type |
| 2544 | * (SYNC, SYNC_NOIDLE, ASYNC), and to compute a workload |
| 2545 | * expiration time |
| 2546 | */ |
Vivek Goyal | 65b32a5 | 2009-12-16 17:52:59 -0500 | [diff] [blame] | 2547 | st = service_tree_for(cfqg, cfqd->serving_prio, cfqd->serving_type); |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 2548 | count = st->count; |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2549 | |
| 2550 | /* |
Vivek Goyal | 65b32a5 | 2009-12-16 17:52:59 -0500 | [diff] [blame] | 2551 | * check workload expiration, and that we still have other queues ready |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2552 | */ |
Vivek Goyal | 65b32a5 | 2009-12-16 17:52:59 -0500 | [diff] [blame] | 2553 | if (count && !time_after(jiffies, cfqd->workload_expires)) |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2554 | return; |
| 2555 | |
Shaohua Li writes | e4ea0c1 | 2010-12-13 14:32:22 +0100 | [diff] [blame] | 2556 | new_workload: |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2557 | /* otherwise select new workload type */ |
| 2558 | cfqd->serving_type = |
Vivek Goyal | 65b32a5 | 2009-12-16 17:52:59 -0500 | [diff] [blame] | 2559 | cfq_choose_wl(cfqd, cfqg, cfqd->serving_prio); |
| 2560 | st = service_tree_for(cfqg, cfqd->serving_prio, cfqd->serving_type); |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 2561 | count = st->count; |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2562 | |
| 2563 | /* |
| 2564 | * the workload slice is computed as a fraction of target latency |
| 2565 | * proportional to the number of queues in that workload, over |
| 2566 | * all the queues in the same priority class |
| 2567 | */ |
Vivek Goyal | 58ff82f | 2009-12-03 12:59:44 -0500 | [diff] [blame] | 2568 | group_slice = cfq_group_slice(cfqd, cfqg); |
| 2569 | |
| 2570 | slice = group_slice * count / |
| 2571 | max_t(unsigned, cfqg->busy_queues_avg[cfqd->serving_prio], |
| 2572 | cfq_group_busy_queues_wl(cfqd->serving_prio, cfqd, cfqg)); |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2573 | |
Vivek Goyal | f26bd1f | 2009-12-03 12:59:54 -0500 | [diff] [blame] | 2574 | if (cfqd->serving_type == ASYNC_WORKLOAD) { |
| 2575 | unsigned int tmp; |
| 2576 | |
| 2577 | /* |
| 2578 | * Async queues are currently system wide. Just taking |
| 2579 | * proportion of queues with-in same group will lead to higher |
| 2580 | * async ratio system wide as generally root group is going |
| 2581 | * to have higher weight. A more accurate thing would be to |
| 2582 | * calculate system wide asnc/sync ratio. |
| 2583 | */ |
Tao Ma | 5bf14c0 | 2012-04-01 14:33:39 -0700 | [diff] [blame] | 2584 | tmp = cfqd->cfq_target_latency * |
| 2585 | cfqg_busy_async_queues(cfqd, cfqg); |
Vivek Goyal | f26bd1f | 2009-12-03 12:59:54 -0500 | [diff] [blame] | 2586 | tmp = tmp/cfqd->busy_queues; |
| 2587 | slice = min_t(unsigned, slice, tmp); |
| 2588 | |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2589 | /* async workload slice is scaled down according to |
| 2590 | * the sync/async slice ratio. */ |
| 2591 | slice = slice * cfqd->cfq_slice[0] / cfqd->cfq_slice[1]; |
Vivek Goyal | f26bd1f | 2009-12-03 12:59:54 -0500 | [diff] [blame] | 2592 | } else |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2593 | /* sync workload slice is at least 2 * cfq_slice_idle */ |
| 2594 | slice = max(slice, 2 * cfqd->cfq_slice_idle); |
| 2595 | |
| 2596 | slice = max_t(unsigned, slice, CFQ_MIN_TT); |
Divyesh Shah | b1ffe73 | 2010-03-25 15:45:03 +0100 | [diff] [blame] | 2597 | cfq_log(cfqd, "workload slice:%d", slice); |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2598 | cfqd->workload_expires = jiffies + slice; |
| 2599 | } |
| 2600 | |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 2601 | static struct cfq_group *cfq_get_next_cfqg(struct cfq_data *cfqd) |
| 2602 | { |
| 2603 | struct cfq_rb_root *st = &cfqd->grp_service_tree; |
Vivek Goyal | 25bc6b0 | 2009-12-03 12:59:43 -0500 | [diff] [blame] | 2604 | struct cfq_group *cfqg; |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 2605 | |
| 2606 | if (RB_EMPTY_ROOT(&st->rb)) |
| 2607 | return NULL; |
Vivek Goyal | 25bc6b0 | 2009-12-03 12:59:43 -0500 | [diff] [blame] | 2608 | cfqg = cfq_rb_first_group(st); |
Vivek Goyal | 25bc6b0 | 2009-12-03 12:59:43 -0500 | [diff] [blame] | 2609 | update_min_vdisktime(st); |
| 2610 | return cfqg; |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 2611 | } |
| 2612 | |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 2613 | static void cfq_choose_cfqg(struct cfq_data *cfqd) |
| 2614 | { |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 2615 | struct cfq_group *cfqg = cfq_get_next_cfqg(cfqd); |
| 2616 | |
| 2617 | cfqd->serving_group = cfqg; |
Vivek Goyal | dae739e | 2009-12-03 12:59:45 -0500 | [diff] [blame] | 2618 | |
| 2619 | /* Restore the workload type data */ |
| 2620 | if (cfqg->saved_workload_slice) { |
| 2621 | cfqd->workload_expires = jiffies + cfqg->saved_workload_slice; |
| 2622 | cfqd->serving_type = cfqg->saved_workload; |
| 2623 | cfqd->serving_prio = cfqg->saved_serving_prio; |
Gui Jianfeng | 66ae291 | 2009-12-15 10:08:45 +0100 | [diff] [blame] | 2624 | } else |
| 2625 | cfqd->workload_expires = jiffies - 1; |
| 2626 | |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 2627 | choose_service_tree(cfqd, cfqg); |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 2628 | } |
| 2629 | |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 2630 | /* |
Jens Axboe | 498d3aa2 | 2007-04-26 12:54:48 +0200 | [diff] [blame] | 2631 | * Select a queue for service. If we have a current active queue, |
| 2632 | * check whether to continue servicing it, or retrieve and set a new one. |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2633 | */ |
Tejun Heo | 1b5ed5e1 | 2005-11-10 08:49:19 +0100 | [diff] [blame] | 2634 | static struct cfq_queue *cfq_select_queue(struct cfq_data *cfqd) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2635 | { |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2636 | struct cfq_queue *cfqq, *new_cfqq = NULL; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2637 | |
| 2638 | cfqq = cfqd->active_queue; |
| 2639 | if (!cfqq) |
| 2640 | goto new_queue; |
| 2641 | |
Vivek Goyal | f04a642 | 2009-12-03 12:59:40 -0500 | [diff] [blame] | 2642 | if (!cfqd->rq_queued) |
| 2643 | return NULL; |
Vivek Goyal | c244bb5 | 2009-12-08 17:52:57 -0500 | [diff] [blame] | 2644 | |
| 2645 | /* |
| 2646 | * We were waiting for group to get backlogged. Expire the queue |
| 2647 | */ |
| 2648 | if (cfq_cfqq_wait_busy(cfqq) && !RB_EMPTY_ROOT(&cfqq->sort_list)) |
| 2649 | goto expire; |
| 2650 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2651 | /* |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2652 | * The active queue has run out of time, expire it and select new. |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2653 | */ |
Vivek Goyal | 7667aa0 | 2009-12-08 17:52:58 -0500 | [diff] [blame] | 2654 | if (cfq_slice_used(cfqq) && !cfq_cfqq_must_dispatch(cfqq)) { |
| 2655 | /* |
| 2656 | * If slice had not expired at the completion of last request |
| 2657 | * we might not have turned on wait_busy flag. Don't expire |
| 2658 | * the queue yet. Allow the group to get backlogged. |
| 2659 | * |
| 2660 | * The very fact that we have used the slice, that means we |
| 2661 | * have been idling all along on this queue and it should be |
| 2662 | * ok to wait for this request to complete. |
| 2663 | */ |
Vivek Goyal | 82bbbf2 | 2009-12-10 19:25:41 +0100 | [diff] [blame] | 2664 | if (cfqq->cfqg->nr_cfqq == 1 && RB_EMPTY_ROOT(&cfqq->sort_list) |
| 2665 | && cfqq->dispatched && cfq_should_idle(cfqd, cfqq)) { |
| 2666 | cfqq = NULL; |
Vivek Goyal | 7667aa0 | 2009-12-08 17:52:58 -0500 | [diff] [blame] | 2667 | goto keep_queue; |
Vivek Goyal | 82bbbf2 | 2009-12-10 19:25:41 +0100 | [diff] [blame] | 2668 | } else |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 2669 | goto check_group_idle; |
Vivek Goyal | 7667aa0 | 2009-12-08 17:52:58 -0500 | [diff] [blame] | 2670 | } |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2671 | |
| 2672 | /* |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2673 | * The active queue has requests and isn't expired, allow it to |
| 2674 | * dispatch. |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2675 | */ |
Jens Axboe | dd67d05 | 2006-06-21 09:36:18 +0200 | [diff] [blame] | 2676 | if (!RB_EMPTY_ROOT(&cfqq->sort_list)) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2677 | goto keep_queue; |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2678 | |
| 2679 | /* |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2680 | * If another queue has a request waiting within our mean seek |
| 2681 | * distance, let it run. The expire code will check for close |
| 2682 | * cooperators and put the close queue at the front of the service |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 2683 | * tree. If possible, merge the expiring queue with the new cfqq. |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2684 | */ |
Jeff Moyer | b3b6d04 | 2009-10-23 17:14:51 -0400 | [diff] [blame] | 2685 | new_cfqq = cfq_close_cooperator(cfqd, cfqq); |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 2686 | if (new_cfqq) { |
| 2687 | if (!cfqq->new_cfqq) |
| 2688 | cfq_setup_merge(cfqq, new_cfqq); |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2689 | goto expire; |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 2690 | } |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2691 | |
| 2692 | /* |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 2693 | * No requests pending. If the active queue still has requests in |
| 2694 | * flight or is idling for a new request, allow either of these |
| 2695 | * conditions to happen (or time out) before selecting a new queue. |
| 2696 | */ |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 2697 | if (timer_pending(&cfqd->idle_slice_timer)) { |
| 2698 | cfqq = NULL; |
| 2699 | goto keep_queue; |
| 2700 | } |
| 2701 | |
Shaohua Li | 8e1ac66 | 2010-11-08 15:01:04 +0100 | [diff] [blame] | 2702 | /* |
| 2703 | * This is a deep seek queue, but the device is much faster than |
| 2704 | * the queue can deliver, don't idle |
| 2705 | **/ |
| 2706 | if (CFQQ_SEEKY(cfqq) && cfq_cfqq_idle_window(cfqq) && |
| 2707 | (cfq_cfqq_slice_new(cfqq) || |
| 2708 | (cfqq->slice_end - jiffies > jiffies - cfqq->slice_start))) { |
| 2709 | cfq_clear_cfqq_deep(cfqq); |
| 2710 | cfq_clear_cfqq_idle_window(cfqq); |
| 2711 | } |
| 2712 | |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 2713 | if (cfqq->dispatched && cfq_should_idle(cfqd, cfqq)) { |
| 2714 | cfqq = NULL; |
| 2715 | goto keep_queue; |
| 2716 | } |
| 2717 | |
| 2718 | /* |
| 2719 | * If group idle is enabled and there are requests dispatched from |
| 2720 | * this group, wait for requests to complete. |
| 2721 | */ |
| 2722 | check_group_idle: |
Shaohua Li | 7700fc4 | 2011-07-12 14:24:56 +0200 | [diff] [blame] | 2723 | if (cfqd->cfq_group_idle && cfqq->cfqg->nr_cfqq == 1 && |
| 2724 | cfqq->cfqg->dispatched && |
| 2725 | !cfq_io_thinktime_big(cfqd, &cfqq->cfqg->ttime, true)) { |
Jens Axboe | caaa5f9 | 2006-06-16 11:23:00 +0200 | [diff] [blame] | 2726 | cfqq = NULL; |
| 2727 | goto keep_queue; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2728 | } |
| 2729 | |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 2730 | expire: |
Vivek Goyal | e5ff082 | 2010-04-26 19:25:11 +0200 | [diff] [blame] | 2731 | cfq_slice_expired(cfqd, 0); |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 2732 | new_queue: |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2733 | /* |
| 2734 | * Current queue expired. Check if we have to switch to a new |
| 2735 | * service tree |
| 2736 | */ |
| 2737 | if (!new_cfqq) |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 2738 | cfq_choose_cfqg(cfqd); |
Corrado Zoccolo | 718eee0 | 2009-10-26 22:45:29 +0100 | [diff] [blame] | 2739 | |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 2740 | cfqq = cfq_set_active_queue(cfqd, new_cfqq); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2741 | keep_queue: |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 2742 | return cfqq; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2743 | } |
| 2744 | |
Jens Axboe | febffd6 | 2008-01-28 13:19:43 +0100 | [diff] [blame] | 2745 | static int __cfq_forced_dispatch_cfqq(struct cfq_queue *cfqq) |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 2746 | { |
| 2747 | int dispatched = 0; |
| 2748 | |
| 2749 | while (cfqq->next_rq) { |
| 2750 | cfq_dispatch_insert(cfqq->cfqd->queue, cfqq->next_rq); |
| 2751 | dispatched++; |
| 2752 | } |
| 2753 | |
| 2754 | BUG_ON(!list_empty(&cfqq->fifo)); |
Vivek Goyal | f04a642 | 2009-12-03 12:59:40 -0500 | [diff] [blame] | 2755 | |
| 2756 | /* By default cfqq is not expired if it is empty. Do it explicitly */ |
Vivek Goyal | e5ff082 | 2010-04-26 19:25:11 +0200 | [diff] [blame] | 2757 | __cfq_slice_expired(cfqq->cfqd, cfqq, 0); |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 2758 | return dispatched; |
| 2759 | } |
| 2760 | |
Jens Axboe | 498d3aa2 | 2007-04-26 12:54:48 +0200 | [diff] [blame] | 2761 | /* |
| 2762 | * Drain our current requests. Used for barriers and when switching |
| 2763 | * io schedulers on-the-fly. |
| 2764 | */ |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 2765 | static int cfq_forced_dispatch(struct cfq_data *cfqd) |
Tejun Heo | 1b5ed5e1 | 2005-11-10 08:49:19 +0100 | [diff] [blame] | 2766 | { |
Jens Axboe | 0871714 | 2008-01-28 11:38:15 +0100 | [diff] [blame] | 2767 | struct cfq_queue *cfqq; |
Jens Axboe | d9e7620 | 2007-04-20 14:27:50 +0200 | [diff] [blame] | 2768 | int dispatched = 0; |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 2769 | |
Divyesh Shah | 3440c49 | 2010-04-09 09:29:57 +0200 | [diff] [blame] | 2770 | /* Expire the timeslice of the current active queue first */ |
Vivek Goyal | e5ff082 | 2010-04-26 19:25:11 +0200 | [diff] [blame] | 2771 | cfq_slice_expired(cfqd, 0); |
Divyesh Shah | 3440c49 | 2010-04-09 09:29:57 +0200 | [diff] [blame] | 2772 | while ((cfqq = cfq_get_next_queue_forced(cfqd)) != NULL) { |
| 2773 | __cfq_set_active_queue(cfqd, cfqq); |
Vivek Goyal | f04a642 | 2009-12-03 12:59:40 -0500 | [diff] [blame] | 2774 | dispatched += __cfq_forced_dispatch_cfqq(cfqq); |
Divyesh Shah | 3440c49 | 2010-04-09 09:29:57 +0200 | [diff] [blame] | 2775 | } |
Tejun Heo | 1b5ed5e1 | 2005-11-10 08:49:19 +0100 | [diff] [blame] | 2776 | |
Tejun Heo | 1b5ed5e1 | 2005-11-10 08:49:19 +0100 | [diff] [blame] | 2777 | BUG_ON(cfqd->busy_queues); |
| 2778 | |
Jeff Moyer | 6923715a | 2009-06-12 15:29:30 +0200 | [diff] [blame] | 2779 | cfq_log(cfqd, "forced_dispatch=%d", dispatched); |
Tejun Heo | 1b5ed5e1 | 2005-11-10 08:49:19 +0100 | [diff] [blame] | 2780 | return dispatched; |
| 2781 | } |
| 2782 | |
Shaohua Li | abc3c74 | 2010-03-01 09:20:54 +0100 | [diff] [blame] | 2783 | static inline bool cfq_slice_used_soon(struct cfq_data *cfqd, |
| 2784 | struct cfq_queue *cfqq) |
| 2785 | { |
| 2786 | /* the queue hasn't finished any request, can't estimate */ |
| 2787 | if (cfq_cfqq_slice_new(cfqq)) |
Shaohua Li | c1e4475 | 2010-11-08 15:01:02 +0100 | [diff] [blame] | 2788 | return true; |
Shaohua Li | abc3c74 | 2010-03-01 09:20:54 +0100 | [diff] [blame] | 2789 | if (time_after(jiffies + cfqd->cfq_slice_idle * cfqq->dispatched, |
| 2790 | cfqq->slice_end)) |
Shaohua Li | c1e4475 | 2010-11-08 15:01:02 +0100 | [diff] [blame] | 2791 | return true; |
Shaohua Li | abc3c74 | 2010-03-01 09:20:54 +0100 | [diff] [blame] | 2792 | |
Shaohua Li | c1e4475 | 2010-11-08 15:01:02 +0100 | [diff] [blame] | 2793 | return false; |
Shaohua Li | abc3c74 | 2010-03-01 09:20:54 +0100 | [diff] [blame] | 2794 | } |
| 2795 | |
Jens Axboe | 0b182d6 | 2009-10-06 20:49:37 +0200 | [diff] [blame] | 2796 | static bool cfq_may_dispatch(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2797 | { |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2798 | unsigned int max_dispatch; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2799 | |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2800 | /* |
Jens Axboe | 5ad531d | 2009-07-03 12:57:48 +0200 | [diff] [blame] | 2801 | * Drain async requests before we start sync IO |
| 2802 | */ |
Corrado Zoccolo | 53c583d | 2010-02-28 19:45:05 +0100 | [diff] [blame] | 2803 | if (cfq_should_idle(cfqd, cfqq) && cfqd->rq_in_flight[BLK_RW_ASYNC]) |
Jens Axboe | 0b182d6 | 2009-10-06 20:49:37 +0200 | [diff] [blame] | 2804 | return false; |
Jens Axboe | 5ad531d | 2009-07-03 12:57:48 +0200 | [diff] [blame] | 2805 | |
| 2806 | /* |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2807 | * If this is an async queue and we have sync IO in flight, let it wait |
| 2808 | */ |
Corrado Zoccolo | 53c583d | 2010-02-28 19:45:05 +0100 | [diff] [blame] | 2809 | if (cfqd->rq_in_flight[BLK_RW_SYNC] && !cfq_cfqq_sync(cfqq)) |
Jens Axboe | 0b182d6 | 2009-10-06 20:49:37 +0200 | [diff] [blame] | 2810 | return false; |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2811 | |
Shaohua Li | abc3c74 | 2010-03-01 09:20:54 +0100 | [diff] [blame] | 2812 | max_dispatch = max_t(unsigned int, cfqd->cfq_quantum / 2, 1); |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2813 | if (cfq_class_idle(cfqq)) |
| 2814 | max_dispatch = 1; |
| 2815 | |
| 2816 | /* |
| 2817 | * Does this cfqq already have too much IO in flight? |
| 2818 | */ |
| 2819 | if (cfqq->dispatched >= max_dispatch) { |
Shaohua Li | ef8a41d | 2011-03-07 09:26:29 +0100 | [diff] [blame] | 2820 | bool promote_sync = false; |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2821 | /* |
| 2822 | * idle queue must always only have a single IO in flight |
| 2823 | */ |
Jens Axboe | 3ed9a29 | 2007-04-23 08:33:33 +0200 | [diff] [blame] | 2824 | if (cfq_class_idle(cfqq)) |
Jens Axboe | 0b182d6 | 2009-10-06 20:49:37 +0200 | [diff] [blame] | 2825 | return false; |
Jens Axboe | 3ed9a29 | 2007-04-23 08:33:33 +0200 | [diff] [blame] | 2826 | |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2827 | /* |
Li, Shaohua | c4ade94 | 2011-03-23 08:30:34 +0100 | [diff] [blame] | 2828 | * If there is only one sync queue |
| 2829 | * we can ignore async queue here and give the sync |
Shaohua Li | ef8a41d | 2011-03-07 09:26:29 +0100 | [diff] [blame] | 2830 | * queue no dispatch limit. The reason is a sync queue can |
| 2831 | * preempt async queue, limiting the sync queue doesn't make |
| 2832 | * sense. This is useful for aiostress test. |
| 2833 | */ |
Li, Shaohua | c4ade94 | 2011-03-23 08:30:34 +0100 | [diff] [blame] | 2834 | if (cfq_cfqq_sync(cfqq) && cfqd->busy_sync_queues == 1) |
| 2835 | promote_sync = true; |
Shaohua Li | ef8a41d | 2011-03-07 09:26:29 +0100 | [diff] [blame] | 2836 | |
| 2837 | /* |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2838 | * We have other queues, don't allow more IO from this one |
| 2839 | */ |
Shaohua Li | ef8a41d | 2011-03-07 09:26:29 +0100 | [diff] [blame] | 2840 | if (cfqd->busy_queues > 1 && cfq_slice_used_soon(cfqd, cfqq) && |
| 2841 | !promote_sync) |
Jens Axboe | 0b182d6 | 2009-10-06 20:49:37 +0200 | [diff] [blame] | 2842 | return false; |
Jens Axboe | 9ede209 | 2007-01-19 12:11:44 +1100 | [diff] [blame] | 2843 | |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2844 | /* |
Shaohua Li | 474b18c | 2009-12-03 12:58:05 +0100 | [diff] [blame] | 2845 | * Sole queue user, no limit |
Vivek Goyal | 365722b | 2009-10-03 15:21:27 +0200 | [diff] [blame] | 2846 | */ |
Shaohua Li | ef8a41d | 2011-03-07 09:26:29 +0100 | [diff] [blame] | 2847 | if (cfqd->busy_queues == 1 || promote_sync) |
Shaohua Li | abc3c74 | 2010-03-01 09:20:54 +0100 | [diff] [blame] | 2848 | max_dispatch = -1; |
| 2849 | else |
| 2850 | /* |
| 2851 | * Normally we start throttling cfqq when cfq_quantum/2 |
| 2852 | * requests have been dispatched. But we can drive |
| 2853 | * deeper queue depths at the beginning of slice |
| 2854 | * subjected to upper limit of cfq_quantum. |
| 2855 | * */ |
| 2856 | max_dispatch = cfqd->cfq_quantum; |
Jens Axboe | 8e29675 | 2009-10-03 16:26:03 +0200 | [diff] [blame] | 2857 | } |
| 2858 | |
| 2859 | /* |
| 2860 | * Async queues must wait a bit before being allowed dispatch. |
| 2861 | * We also ramp up the dispatch depth gradually for async IO, |
| 2862 | * based on the last sync IO we serviced |
| 2863 | */ |
Jens Axboe | 963b72f | 2009-10-03 19:42:18 +0200 | [diff] [blame] | 2864 | if (!cfq_cfqq_sync(cfqq) && cfqd->cfq_latency) { |
Corrado Zoccolo | 573412b | 2009-12-06 11:48:52 +0100 | [diff] [blame] | 2865 | unsigned long last_sync = jiffies - cfqd->last_delayed_sync; |
Jens Axboe | 8e29675 | 2009-10-03 16:26:03 +0200 | [diff] [blame] | 2866 | unsigned int depth; |
Vivek Goyal | 365722b | 2009-10-03 15:21:27 +0200 | [diff] [blame] | 2867 | |
Jens Axboe | 61f0c1d | 2009-10-03 19:46:03 +0200 | [diff] [blame] | 2868 | depth = last_sync / cfqd->cfq_slice[1]; |
Jens Axboe | e00c54c | 2009-10-04 20:36:19 +0200 | [diff] [blame] | 2869 | if (!depth && !cfqq->dispatched) |
| 2870 | depth = 1; |
Jens Axboe | 8e29675 | 2009-10-03 16:26:03 +0200 | [diff] [blame] | 2871 | if (depth < max_dispatch) |
| 2872 | max_dispatch = depth; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2873 | } |
| 2874 | |
Jens Axboe | 0b182d6 | 2009-10-06 20:49:37 +0200 | [diff] [blame] | 2875 | /* |
| 2876 | * If we're below the current max, allow a dispatch |
| 2877 | */ |
| 2878 | return cfqq->dispatched < max_dispatch; |
| 2879 | } |
| 2880 | |
| 2881 | /* |
| 2882 | * Dispatch a request from cfqq, moving them to the request queue |
| 2883 | * dispatch list. |
| 2884 | */ |
| 2885 | static bool cfq_dispatch_request(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
| 2886 | { |
| 2887 | struct request *rq; |
| 2888 | |
| 2889 | BUG_ON(RB_EMPTY_ROOT(&cfqq->sort_list)); |
| 2890 | |
| 2891 | if (!cfq_may_dispatch(cfqd, cfqq)) |
| 2892 | return false; |
| 2893 | |
| 2894 | /* |
| 2895 | * follow expired path, else get first next available |
| 2896 | */ |
| 2897 | rq = cfq_check_fifo(cfqq); |
| 2898 | if (!rq) |
| 2899 | rq = cfqq->next_rq; |
| 2900 | |
| 2901 | /* |
| 2902 | * insert request into driver dispatch list |
| 2903 | */ |
| 2904 | cfq_dispatch_insert(cfqd->queue, rq); |
| 2905 | |
| 2906 | if (!cfqd->active_cic) { |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 2907 | struct cfq_io_cq *cic = RQ_CIC(rq); |
Jens Axboe | 0b182d6 | 2009-10-06 20:49:37 +0200 | [diff] [blame] | 2908 | |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 2909 | atomic_long_inc(&cic->icq.ioc->refcount); |
Jens Axboe | 0b182d6 | 2009-10-06 20:49:37 +0200 | [diff] [blame] | 2910 | cfqd->active_cic = cic; |
| 2911 | } |
| 2912 | |
| 2913 | return true; |
| 2914 | } |
| 2915 | |
| 2916 | /* |
| 2917 | * Find the cfqq that we need to service and move a request from that to the |
| 2918 | * dispatch list |
| 2919 | */ |
| 2920 | static int cfq_dispatch_requests(struct request_queue *q, int force) |
| 2921 | { |
| 2922 | struct cfq_data *cfqd = q->elevator->elevator_data; |
| 2923 | struct cfq_queue *cfqq; |
| 2924 | |
| 2925 | if (!cfqd->busy_queues) |
| 2926 | return 0; |
| 2927 | |
| 2928 | if (unlikely(force)) |
| 2929 | return cfq_forced_dispatch(cfqd); |
| 2930 | |
| 2931 | cfqq = cfq_select_queue(cfqd); |
| 2932 | if (!cfqq) |
Jens Axboe | 8e29675 | 2009-10-03 16:26:03 +0200 | [diff] [blame] | 2933 | return 0; |
| 2934 | |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2935 | /* |
Jens Axboe | 0b182d6 | 2009-10-06 20:49:37 +0200 | [diff] [blame] | 2936 | * Dispatch a request from this cfqq, if it is allowed |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2937 | */ |
Jens Axboe | 0b182d6 | 2009-10-06 20:49:37 +0200 | [diff] [blame] | 2938 | if (!cfq_dispatch_request(cfqd, cfqq)) |
| 2939 | return 0; |
| 2940 | |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2941 | cfqq->slice_dispatch++; |
Jens Axboe | b029195 | 2009-04-07 11:38:31 +0200 | [diff] [blame] | 2942 | cfq_clear_cfqq_must_dispatch(cfqq); |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2943 | |
| 2944 | /* |
| 2945 | * expire an async queue immediately if it has used up its slice. idle |
| 2946 | * queue always expire after 1 dispatch round. |
| 2947 | */ |
| 2948 | if (cfqd->busy_queues > 1 && ((!cfq_cfqq_sync(cfqq) && |
| 2949 | cfqq->slice_dispatch >= cfq_prio_to_maxrq(cfqd, cfqq)) || |
| 2950 | cfq_class_idle(cfqq))) { |
| 2951 | cfqq->slice_end = jiffies + 1; |
Vivek Goyal | e5ff082 | 2010-04-26 19:25:11 +0200 | [diff] [blame] | 2952 | cfq_slice_expired(cfqd, 0); |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2953 | } |
| 2954 | |
Shan Wei | b217a90 | 2009-09-01 10:06:42 +0200 | [diff] [blame] | 2955 | cfq_log_cfqq(cfqd, cfqq, "dispatched a request"); |
Jens Axboe | 2f5cb73 | 2009-04-07 08:51:19 +0200 | [diff] [blame] | 2956 | return 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2957 | } |
| 2958 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2959 | /* |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 2960 | * task holds one reference to the queue, dropped when task exits. each rq |
| 2961 | * in-flight on this queue also holds a reference, dropped when rq is freed. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2962 | * |
Vivek Goyal | b1c3576 | 2009-12-03 12:59:47 -0500 | [diff] [blame] | 2963 | * Each cfq queue took a reference on the parent group. Drop it now. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2964 | * queue lock must be held here. |
| 2965 | */ |
| 2966 | static void cfq_put_queue(struct cfq_queue *cfqq) |
| 2967 | { |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2968 | struct cfq_data *cfqd = cfqq->cfqd; |
Justin TerAvest | 0bbfeb8 | 2011-03-01 15:05:08 -0500 | [diff] [blame] | 2969 | struct cfq_group *cfqg; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2970 | |
Shaohua Li | 30d7b94 | 2011-01-07 08:46:59 +0100 | [diff] [blame] | 2971 | BUG_ON(cfqq->ref <= 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2972 | |
Shaohua Li | 30d7b94 | 2011-01-07 08:46:59 +0100 | [diff] [blame] | 2973 | cfqq->ref--; |
| 2974 | if (cfqq->ref) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2975 | return; |
| 2976 | |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 2977 | cfq_log_cfqq(cfqd, cfqq, "put_queue"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2978 | BUG_ON(rb_first(&cfqq->sort_list)); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2979 | BUG_ON(cfqq->allocated[READ] + cfqq->allocated[WRITE]); |
Vivek Goyal | b1c3576 | 2009-12-03 12:59:47 -0500 | [diff] [blame] | 2980 | cfqg = cfqq->cfqg; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2981 | |
Jens Axboe | 28f95cbc | 2007-01-19 12:09:53 +1100 | [diff] [blame] | 2982 | if (unlikely(cfqd->active_queue == cfqq)) { |
Vivek Goyal | e5ff082 | 2010-04-26 19:25:11 +0200 | [diff] [blame] | 2983 | __cfq_slice_expired(cfqd, cfqq, 0); |
Jens Axboe | 23e018a | 2009-10-05 08:52:35 +0200 | [diff] [blame] | 2984 | cfq_schedule_dispatch(cfqd); |
Jens Axboe | 28f95cbc | 2007-01-19 12:09:53 +1100 | [diff] [blame] | 2985 | } |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2986 | |
Vivek Goyal | f04a642 | 2009-12-03 12:59:40 -0500 | [diff] [blame] | 2987 | BUG_ON(cfq_cfqq_on_rr(cfqq)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2988 | kmem_cache_free(cfq_pool, cfqq); |
Tejun Heo | eb7d8c07 | 2012-03-23 14:02:53 +0100 | [diff] [blame] | 2989 | cfqg_put(cfqg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2990 | } |
| 2991 | |
Shaohua Li | d02a2c0 | 2010-05-25 10:16:53 +0200 | [diff] [blame] | 2992 | static void cfq_put_cooperator(struct cfq_queue *cfqq) |
Jens Axboe | 89850f7 | 2006-07-22 16:48:31 +0200 | [diff] [blame] | 2993 | { |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 2994 | struct cfq_queue *__cfqq, *next; |
| 2995 | |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 2996 | /* |
| 2997 | * If this queue was scheduled to merge with another queue, be |
| 2998 | * sure to drop the reference taken on that queue (and others in |
| 2999 | * the merge chain). See cfq_setup_merge and cfq_merge_cfqqs. |
| 3000 | */ |
| 3001 | __cfqq = cfqq->new_cfqq; |
| 3002 | while (__cfqq) { |
| 3003 | if (__cfqq == cfqq) { |
| 3004 | WARN(1, "cfqq->new_cfqq loop detected\n"); |
| 3005 | break; |
| 3006 | } |
| 3007 | next = __cfqq->new_cfqq; |
| 3008 | cfq_put_queue(__cfqq); |
| 3009 | __cfqq = next; |
| 3010 | } |
Shaohua Li | d02a2c0 | 2010-05-25 10:16:53 +0200 | [diff] [blame] | 3011 | } |
| 3012 | |
| 3013 | static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
| 3014 | { |
| 3015 | if (unlikely(cfqq == cfqd->active_queue)) { |
| 3016 | __cfq_slice_expired(cfqd, cfqq, 0); |
| 3017 | cfq_schedule_dispatch(cfqd); |
| 3018 | } |
| 3019 | |
| 3020 | cfq_put_cooperator(cfqq); |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 3021 | |
Jens Axboe | 89850f7 | 2006-07-22 16:48:31 +0200 | [diff] [blame] | 3022 | cfq_put_queue(cfqq); |
| 3023 | } |
| 3024 | |
Tejun Heo | 9b84cac | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 3025 | static void cfq_init_icq(struct io_cq *icq) |
| 3026 | { |
| 3027 | struct cfq_io_cq *cic = icq_to_cic(icq); |
| 3028 | |
| 3029 | cic->ttime.last_end_request = jiffies; |
| 3030 | } |
| 3031 | |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 3032 | static void cfq_exit_icq(struct io_cq *icq) |
Jens Axboe | 89850f7 | 2006-07-22 16:48:31 +0200 | [diff] [blame] | 3033 | { |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 3034 | struct cfq_io_cq *cic = icq_to_cic(icq); |
Tejun Heo | 283287a | 2011-12-14 00:33:38 +0100 | [diff] [blame] | 3035 | struct cfq_data *cfqd = cic_to_cfqd(cic); |
Fabio Checconi | 4faa3c8 | 2008-04-10 08:28:01 +0200 | [diff] [blame] | 3036 | |
Jens Axboe | ff6657c | 2009-04-08 10:58:57 +0200 | [diff] [blame] | 3037 | if (cic->cfqq[BLK_RW_ASYNC]) { |
| 3038 | cfq_exit_cfqq(cfqd, cic->cfqq[BLK_RW_ASYNC]); |
| 3039 | cic->cfqq[BLK_RW_ASYNC] = NULL; |
Jens Axboe | 89850f7 | 2006-07-22 16:48:31 +0200 | [diff] [blame] | 3040 | } |
| 3041 | |
Jens Axboe | ff6657c | 2009-04-08 10:58:57 +0200 | [diff] [blame] | 3042 | if (cic->cfqq[BLK_RW_SYNC]) { |
| 3043 | cfq_exit_cfqq(cfqd, cic->cfqq[BLK_RW_SYNC]); |
| 3044 | cic->cfqq[BLK_RW_SYNC] = NULL; |
Jens Axboe | 89850f7 | 2006-07-22 16:48:31 +0200 | [diff] [blame] | 3045 | } |
Jens Axboe | 89850f7 | 2006-07-22 16:48:31 +0200 | [diff] [blame] | 3046 | } |
| 3047 | |
Tejun Heo | abede6d | 2012-03-19 15:10:57 -0700 | [diff] [blame] | 3048 | static void cfq_init_prio_data(struct cfq_queue *cfqq, struct cfq_io_cq *cic) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3049 | { |
| 3050 | struct task_struct *tsk = current; |
| 3051 | int ioprio_class; |
| 3052 | |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 3053 | if (!cfq_cfqq_prio_changed(cfqq)) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3054 | return; |
| 3055 | |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3056 | ioprio_class = IOPRIO_PRIO_CLASS(cic->ioprio); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3057 | switch (ioprio_class) { |
Jens Axboe | fe094d9 | 2008-01-31 13:08:54 +0100 | [diff] [blame] | 3058 | default: |
| 3059 | printk(KERN_ERR "cfq: bad prio %x\n", ioprio_class); |
| 3060 | case IOPRIO_CLASS_NONE: |
| 3061 | /* |
Jens Axboe | 6d63c27 | 2008-05-07 09:51:23 +0200 | [diff] [blame] | 3062 | * no prio set, inherit CPU scheduling settings |
Jens Axboe | fe094d9 | 2008-01-31 13:08:54 +0100 | [diff] [blame] | 3063 | */ |
| 3064 | cfqq->ioprio = task_nice_ioprio(tsk); |
Jens Axboe | 6d63c27 | 2008-05-07 09:51:23 +0200 | [diff] [blame] | 3065 | cfqq->ioprio_class = task_nice_ioclass(tsk); |
Jens Axboe | fe094d9 | 2008-01-31 13:08:54 +0100 | [diff] [blame] | 3066 | break; |
| 3067 | case IOPRIO_CLASS_RT: |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3068 | cfqq->ioprio = IOPRIO_PRIO_DATA(cic->ioprio); |
Jens Axboe | fe094d9 | 2008-01-31 13:08:54 +0100 | [diff] [blame] | 3069 | cfqq->ioprio_class = IOPRIO_CLASS_RT; |
| 3070 | break; |
| 3071 | case IOPRIO_CLASS_BE: |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3072 | cfqq->ioprio = IOPRIO_PRIO_DATA(cic->ioprio); |
Jens Axboe | fe094d9 | 2008-01-31 13:08:54 +0100 | [diff] [blame] | 3073 | cfqq->ioprio_class = IOPRIO_CLASS_BE; |
| 3074 | break; |
| 3075 | case IOPRIO_CLASS_IDLE: |
| 3076 | cfqq->ioprio_class = IOPRIO_CLASS_IDLE; |
| 3077 | cfqq->ioprio = 7; |
| 3078 | cfq_clear_cfqq_idle_window(cfqq); |
| 3079 | break; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3080 | } |
| 3081 | |
| 3082 | /* |
| 3083 | * keep track of original prio settings in case we have to temporarily |
| 3084 | * elevate the priority of this queue |
| 3085 | */ |
| 3086 | cfqq->org_ioprio = cfqq->ioprio; |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 3087 | cfq_clear_cfqq_prio_changed(cfqq); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3088 | } |
| 3089 | |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3090 | static void check_ioprio_changed(struct cfq_io_cq *cic, struct bio *bio) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3091 | { |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3092 | int ioprio = cic->icq.ioc->ioprio; |
Konstantin Khlebnikov | bca4b91 | 2010-05-20 23:21:34 +0400 | [diff] [blame] | 3093 | struct cfq_data *cfqd = cic_to_cfqd(cic); |
Al Viro | 478a82b | 2006-03-18 13:25:24 -0500 | [diff] [blame] | 3094 | struct cfq_queue *cfqq; |
Jens Axboe | 35e6077 | 2006-06-14 09:10:45 +0200 | [diff] [blame] | 3095 | |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3096 | /* |
| 3097 | * Check whether ioprio has changed. The condition may trigger |
| 3098 | * spuriously on a newly created cic but there's no harm. |
| 3099 | */ |
| 3100 | if (unlikely(!cfqd) || likely(cic->ioprio == ioprio)) |
Jens Axboe | caaa5f9 | 2006-06-16 11:23:00 +0200 | [diff] [blame] | 3101 | return; |
| 3102 | |
Jens Axboe | ff6657c | 2009-04-08 10:58:57 +0200 | [diff] [blame] | 3103 | cfqq = cic->cfqq[BLK_RW_ASYNC]; |
Jens Axboe | caaa5f9 | 2006-06-16 11:23:00 +0200 | [diff] [blame] | 3104 | if (cfqq) { |
| 3105 | struct cfq_queue *new_cfqq; |
Tejun Heo | abede6d | 2012-03-19 15:10:57 -0700 | [diff] [blame] | 3106 | new_cfqq = cfq_get_queue(cfqd, BLK_RW_ASYNC, cic, bio, |
| 3107 | GFP_ATOMIC); |
Jens Axboe | caaa5f9 | 2006-06-16 11:23:00 +0200 | [diff] [blame] | 3108 | if (new_cfqq) { |
Jens Axboe | ff6657c | 2009-04-08 10:58:57 +0200 | [diff] [blame] | 3109 | cic->cfqq[BLK_RW_ASYNC] = new_cfqq; |
Jens Axboe | caaa5f9 | 2006-06-16 11:23:00 +0200 | [diff] [blame] | 3110 | cfq_put_queue(cfqq); |
| 3111 | } |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3112 | } |
Jens Axboe | caaa5f9 | 2006-06-16 11:23:00 +0200 | [diff] [blame] | 3113 | |
Jens Axboe | ff6657c | 2009-04-08 10:58:57 +0200 | [diff] [blame] | 3114 | cfqq = cic->cfqq[BLK_RW_SYNC]; |
Jens Axboe | caaa5f9 | 2006-06-16 11:23:00 +0200 | [diff] [blame] | 3115 | if (cfqq) |
| 3116 | cfq_mark_cfqq_prio_changed(cfqq); |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3117 | |
| 3118 | cic->ioprio = ioprio; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3119 | } |
| 3120 | |
Jens Axboe | d5036d7 | 2009-06-26 10:44:34 +0200 | [diff] [blame] | 3121 | static void cfq_init_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq, |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 3122 | pid_t pid, bool is_sync) |
Jens Axboe | d5036d7 | 2009-06-26 10:44:34 +0200 | [diff] [blame] | 3123 | { |
| 3124 | RB_CLEAR_NODE(&cfqq->rb_node); |
| 3125 | RB_CLEAR_NODE(&cfqq->p_node); |
| 3126 | INIT_LIST_HEAD(&cfqq->fifo); |
| 3127 | |
Shaohua Li | 30d7b94 | 2011-01-07 08:46:59 +0100 | [diff] [blame] | 3128 | cfqq->ref = 0; |
Jens Axboe | d5036d7 | 2009-06-26 10:44:34 +0200 | [diff] [blame] | 3129 | cfqq->cfqd = cfqd; |
| 3130 | |
| 3131 | cfq_mark_cfqq_prio_changed(cfqq); |
| 3132 | |
| 3133 | if (is_sync) { |
| 3134 | if (!cfq_class_idle(cfqq)) |
| 3135 | cfq_mark_cfqq_idle_window(cfqq); |
| 3136 | cfq_mark_cfqq_sync(cfqq); |
| 3137 | } |
| 3138 | cfqq->pid = pid; |
| 3139 | } |
| 3140 | |
Vivek Goyal | 24610333 | 2009-12-03 12:59:51 -0500 | [diff] [blame] | 3141 | #ifdef CONFIG_CFQ_GROUP_IOSCHED |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3142 | static void check_blkcg_changed(struct cfq_io_cq *cic, struct bio *bio) |
Vivek Goyal | 24610333 | 2009-12-03 12:59:51 -0500 | [diff] [blame] | 3143 | { |
Konstantin Khlebnikov | bca4b91 | 2010-05-20 23:21:34 +0400 | [diff] [blame] | 3144 | struct cfq_data *cfqd = cic_to_cfqd(cic); |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3145 | struct cfq_queue *sync_cfqq; |
| 3146 | uint64_t id; |
Vivek Goyal | 24610333 | 2009-12-03 12:59:51 -0500 | [diff] [blame] | 3147 | |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3148 | rcu_read_lock(); |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 3149 | id = bio_blkcg(bio)->id; |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3150 | rcu_read_unlock(); |
| 3151 | |
| 3152 | /* |
| 3153 | * Check whether blkcg has changed. The condition may trigger |
| 3154 | * spuriously on a newly created cic but there's no harm. |
| 3155 | */ |
| 3156 | if (unlikely(!cfqd) || likely(cic->blkcg_id == id)) |
Vivek Goyal | 24610333 | 2009-12-03 12:59:51 -0500 | [diff] [blame] | 3157 | return; |
| 3158 | |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3159 | sync_cfqq = cic_to_cfqq(cic, 1); |
Vivek Goyal | 24610333 | 2009-12-03 12:59:51 -0500 | [diff] [blame] | 3160 | if (sync_cfqq) { |
| 3161 | /* |
| 3162 | * Drop reference to sync queue. A new sync queue will be |
| 3163 | * assigned in new group upon arrival of a fresh request. |
| 3164 | */ |
| 3165 | cfq_log_cfqq(cfqd, sync_cfqq, "changed cgroup"); |
| 3166 | cic_set_cfqq(cic, NULL, 1); |
| 3167 | cfq_put_queue(sync_cfqq); |
| 3168 | } |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3169 | |
| 3170 | cic->blkcg_id = id; |
Vivek Goyal | 24610333 | 2009-12-03 12:59:51 -0500 | [diff] [blame] | 3171 | } |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3172 | #else |
| 3173 | static inline void check_blkcg_changed(struct cfq_io_cq *cic, struct bio *bio) { } |
Vivek Goyal | 24610333 | 2009-12-03 12:59:51 -0500 | [diff] [blame] | 3174 | #endif /* CONFIG_CFQ_GROUP_IOSCHED */ |
| 3175 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3176 | static struct cfq_queue * |
Tejun Heo | abede6d | 2012-03-19 15:10:57 -0700 | [diff] [blame] | 3177 | cfq_find_alloc_queue(struct cfq_data *cfqd, bool is_sync, struct cfq_io_cq *cic, |
| 3178 | struct bio *bio, gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3179 | { |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 3180 | struct blkcg *blkcg; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3181 | struct cfq_queue *cfqq, *new_cfqq = NULL; |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 3182 | struct cfq_group *cfqg; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3183 | |
| 3184 | retry: |
Tejun Heo | 2a7f124 | 2012-03-05 13:15:01 -0800 | [diff] [blame] | 3185 | rcu_read_lock(); |
| 3186 | |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 3187 | blkcg = bio_blkcg(bio); |
Tejun Heo | cd1604f | 2012-03-05 13:15:06 -0800 | [diff] [blame] | 3188 | cfqg = cfq_lookup_create_cfqg(cfqd, blkcg); |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 3189 | cfqq = cic_to_cfqq(cic, is_sync); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3190 | |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 3191 | /* |
| 3192 | * Always try a new alloc if we fell back to the OOM cfqq |
| 3193 | * originally, since it should just be a temporary situation. |
| 3194 | */ |
| 3195 | if (!cfqq || cfqq == &cfqd->oom_cfqq) { |
| 3196 | cfqq = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3197 | if (new_cfqq) { |
| 3198 | cfqq = new_cfqq; |
| 3199 | new_cfqq = NULL; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3200 | } else if (gfp_mask & __GFP_WAIT) { |
Tejun Heo | 2a7f124 | 2012-03-05 13:15:01 -0800 | [diff] [blame] | 3201 | rcu_read_unlock(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3202 | spin_unlock_irq(cfqd->queue->queue_lock); |
Christoph Lameter | 94f6030 | 2007-07-17 04:03:29 -0700 | [diff] [blame] | 3203 | new_cfqq = kmem_cache_alloc_node(cfq_pool, |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 3204 | gfp_mask | __GFP_ZERO, |
Christoph Lameter | 94f6030 | 2007-07-17 04:03:29 -0700 | [diff] [blame] | 3205 | cfqd->queue->node); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3206 | spin_lock_irq(cfqd->queue->queue_lock); |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 3207 | if (new_cfqq) |
| 3208 | goto retry; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3209 | } else { |
Christoph Lameter | 94f6030 | 2007-07-17 04:03:29 -0700 | [diff] [blame] | 3210 | cfqq = kmem_cache_alloc_node(cfq_pool, |
| 3211 | gfp_mask | __GFP_ZERO, |
| 3212 | cfqd->queue->node); |
Kiyoshi Ueda | db3b584 | 2005-06-17 16:15:10 +0200 | [diff] [blame] | 3213 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3214 | |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 3215 | if (cfqq) { |
| 3216 | cfq_init_cfqq(cfqd, cfqq, current->pid, is_sync); |
Tejun Heo | abede6d | 2012-03-19 15:10:57 -0700 | [diff] [blame] | 3217 | cfq_init_prio_data(cfqq, cic); |
Vivek Goyal | cdb16e8 | 2009-12-03 12:59:38 -0500 | [diff] [blame] | 3218 | cfq_link_cfqq_cfqg(cfqq, cfqg); |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 3219 | cfq_log_cfqq(cfqd, cfqq, "alloced"); |
| 3220 | } else |
| 3221 | cfqq = &cfqd->oom_cfqq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3222 | } |
| 3223 | |
| 3224 | if (new_cfqq) |
| 3225 | kmem_cache_free(cfq_pool, new_cfqq); |
| 3226 | |
Tejun Heo | 2a7f124 | 2012-03-05 13:15:01 -0800 | [diff] [blame] | 3227 | rcu_read_unlock(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3228 | return cfqq; |
| 3229 | } |
| 3230 | |
Vasily Tarasov | c2dea2d | 2007-07-20 10:06:38 +0200 | [diff] [blame] | 3231 | static struct cfq_queue ** |
| 3232 | cfq_async_queue_prio(struct cfq_data *cfqd, int ioprio_class, int ioprio) |
| 3233 | { |
Jens Axboe | fe094d9 | 2008-01-31 13:08:54 +0100 | [diff] [blame] | 3234 | switch (ioprio_class) { |
Vasily Tarasov | c2dea2d | 2007-07-20 10:06:38 +0200 | [diff] [blame] | 3235 | case IOPRIO_CLASS_RT: |
| 3236 | return &cfqd->async_cfqq[0][ioprio]; |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3237 | case IOPRIO_CLASS_NONE: |
| 3238 | ioprio = IOPRIO_NORM; |
| 3239 | /* fall through */ |
Vasily Tarasov | c2dea2d | 2007-07-20 10:06:38 +0200 | [diff] [blame] | 3240 | case IOPRIO_CLASS_BE: |
| 3241 | return &cfqd->async_cfqq[1][ioprio]; |
| 3242 | case IOPRIO_CLASS_IDLE: |
| 3243 | return &cfqd->async_idle_cfqq; |
| 3244 | default: |
| 3245 | BUG(); |
| 3246 | } |
| 3247 | } |
| 3248 | |
Jens Axboe | 15c31be | 2007-07-10 13:43:25 +0200 | [diff] [blame] | 3249 | static struct cfq_queue * |
Tejun Heo | abede6d | 2012-03-19 15:10:57 -0700 | [diff] [blame] | 3250 | cfq_get_queue(struct cfq_data *cfqd, bool is_sync, struct cfq_io_cq *cic, |
Tejun Heo | 4f85cb9 | 2012-03-05 13:15:28 -0800 | [diff] [blame] | 3251 | struct bio *bio, gfp_t gfp_mask) |
Jens Axboe | 15c31be | 2007-07-10 13:43:25 +0200 | [diff] [blame] | 3252 | { |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3253 | const int ioprio_class = IOPRIO_PRIO_CLASS(cic->ioprio); |
| 3254 | const int ioprio = IOPRIO_PRIO_DATA(cic->ioprio); |
Vasily Tarasov | c2dea2d | 2007-07-20 10:06:38 +0200 | [diff] [blame] | 3255 | struct cfq_queue **async_cfqq = NULL; |
Jens Axboe | 15c31be | 2007-07-10 13:43:25 +0200 | [diff] [blame] | 3256 | struct cfq_queue *cfqq = NULL; |
| 3257 | |
Vasily Tarasov | c2dea2d | 2007-07-20 10:06:38 +0200 | [diff] [blame] | 3258 | if (!is_sync) { |
| 3259 | async_cfqq = cfq_async_queue_prio(cfqd, ioprio_class, ioprio); |
| 3260 | cfqq = *async_cfqq; |
| 3261 | } |
| 3262 | |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 3263 | if (!cfqq) |
Tejun Heo | abede6d | 2012-03-19 15:10:57 -0700 | [diff] [blame] | 3264 | cfqq = cfq_find_alloc_queue(cfqd, is_sync, cic, bio, gfp_mask); |
Jens Axboe | 15c31be | 2007-07-10 13:43:25 +0200 | [diff] [blame] | 3265 | |
| 3266 | /* |
| 3267 | * pin the queue now that it's allocated, scheduler exit will prune it |
| 3268 | */ |
Vasily Tarasov | c2dea2d | 2007-07-20 10:06:38 +0200 | [diff] [blame] | 3269 | if (!is_sync && !(*async_cfqq)) { |
Shaohua Li | 30d7b94 | 2011-01-07 08:46:59 +0100 | [diff] [blame] | 3270 | cfqq->ref++; |
Vasily Tarasov | c2dea2d | 2007-07-20 10:06:38 +0200 | [diff] [blame] | 3271 | *async_cfqq = cfqq; |
Jens Axboe | 15c31be | 2007-07-10 13:43:25 +0200 | [diff] [blame] | 3272 | } |
| 3273 | |
Shaohua Li | 30d7b94 | 2011-01-07 08:46:59 +0100 | [diff] [blame] | 3274 | cfqq->ref++; |
Jens Axboe | 15c31be | 2007-07-10 13:43:25 +0200 | [diff] [blame] | 3275 | return cfqq; |
| 3276 | } |
| 3277 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3278 | static void |
Shaohua Li | 383cd72 | 2011-07-12 14:24:35 +0200 | [diff] [blame] | 3279 | __cfq_update_io_thinktime(struct cfq_ttime *ttime, unsigned long slice_idle) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3280 | { |
Shaohua Li | 383cd72 | 2011-07-12 14:24:35 +0200 | [diff] [blame] | 3281 | unsigned long elapsed = jiffies - ttime->last_end_request; |
| 3282 | elapsed = min(elapsed, 2UL * slice_idle); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3283 | |
Shaohua Li | 383cd72 | 2011-07-12 14:24:35 +0200 | [diff] [blame] | 3284 | ttime->ttime_samples = (7*ttime->ttime_samples + 256) / 8; |
| 3285 | ttime->ttime_total = (7*ttime->ttime_total + 256*elapsed) / 8; |
| 3286 | ttime->ttime_mean = (ttime->ttime_total + 128) / ttime->ttime_samples; |
| 3287 | } |
| 3288 | |
| 3289 | static void |
| 3290 | cfq_update_io_thinktime(struct cfq_data *cfqd, struct cfq_queue *cfqq, |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 3291 | struct cfq_io_cq *cic) |
Shaohua Li | 383cd72 | 2011-07-12 14:24:35 +0200 | [diff] [blame] | 3292 | { |
Shaohua Li | f5f2b6c | 2011-07-12 14:24:55 +0200 | [diff] [blame] | 3293 | if (cfq_cfqq_sync(cfqq)) { |
Shaohua Li | 383cd72 | 2011-07-12 14:24:35 +0200 | [diff] [blame] | 3294 | __cfq_update_io_thinktime(&cic->ttime, cfqd->cfq_slice_idle); |
Shaohua Li | f5f2b6c | 2011-07-12 14:24:55 +0200 | [diff] [blame] | 3295 | __cfq_update_io_thinktime(&cfqq->service_tree->ttime, |
| 3296 | cfqd->cfq_slice_idle); |
| 3297 | } |
Shaohua Li | 7700fc4 | 2011-07-12 14:24:56 +0200 | [diff] [blame] | 3298 | #ifdef CONFIG_CFQ_GROUP_IOSCHED |
| 3299 | __cfq_update_io_thinktime(&cfqq->cfqg->ttime, cfqd->cfq_group_idle); |
| 3300 | #endif |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3301 | } |
| 3302 | |
Jens Axboe | 206dc69 | 2006-03-28 13:03:44 +0200 | [diff] [blame] | 3303 | static void |
Jeff Moyer | b2c18e1 | 2009-10-23 17:14:49 -0400 | [diff] [blame] | 3304 | cfq_update_io_seektime(struct cfq_data *cfqd, struct cfq_queue *cfqq, |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 3305 | struct request *rq) |
Jens Axboe | 206dc69 | 2006-03-28 13:03:44 +0200 | [diff] [blame] | 3306 | { |
Corrado Zoccolo | 3dde36d | 2010-02-27 19:45:39 +0100 | [diff] [blame] | 3307 | sector_t sdist = 0; |
Corrado Zoccolo | 41647e7 | 2010-02-27 19:45:40 +0100 | [diff] [blame] | 3308 | sector_t n_sec = blk_rq_sectors(rq); |
Corrado Zoccolo | 3dde36d | 2010-02-27 19:45:39 +0100 | [diff] [blame] | 3309 | if (cfqq->last_request_pos) { |
| 3310 | if (cfqq->last_request_pos < blk_rq_pos(rq)) |
| 3311 | sdist = blk_rq_pos(rq) - cfqq->last_request_pos; |
| 3312 | else |
| 3313 | sdist = cfqq->last_request_pos - blk_rq_pos(rq); |
| 3314 | } |
Jens Axboe | 206dc69 | 2006-03-28 13:03:44 +0200 | [diff] [blame] | 3315 | |
Corrado Zoccolo | 3dde36d | 2010-02-27 19:45:39 +0100 | [diff] [blame] | 3316 | cfqq->seek_history <<= 1; |
Corrado Zoccolo | 41647e7 | 2010-02-27 19:45:40 +0100 | [diff] [blame] | 3317 | if (blk_queue_nonrot(cfqd->queue)) |
| 3318 | cfqq->seek_history |= (n_sec < CFQQ_SECT_THR_NONROT); |
| 3319 | else |
| 3320 | cfqq->seek_history |= (sdist > CFQQ_SEEK_THR); |
Jens Axboe | 206dc69 | 2006-03-28 13:03:44 +0200 | [diff] [blame] | 3321 | } |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3322 | |
| 3323 | /* |
| 3324 | * Disable idle window if the process thinks too long or seeks so much that |
| 3325 | * it doesn't matter |
| 3326 | */ |
| 3327 | static void |
| 3328 | cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq, |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 3329 | struct cfq_io_cq *cic) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3330 | { |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 3331 | int old_idle, enable_idle; |
Jens Axboe | 1be92f2f | 2007-04-19 14:32:26 +0200 | [diff] [blame] | 3332 | |
Jens Axboe | 0871714 | 2008-01-28 11:38:15 +0100 | [diff] [blame] | 3333 | /* |
| 3334 | * Don't idle for async or idle io prio class |
| 3335 | */ |
| 3336 | if (!cfq_cfqq_sync(cfqq) || cfq_class_idle(cfqq)) |
Jens Axboe | 1be92f2f | 2007-04-19 14:32:26 +0200 | [diff] [blame] | 3337 | return; |
| 3338 | |
Jens Axboe | c265a7f | 2008-06-26 13:49:33 +0200 | [diff] [blame] | 3339 | enable_idle = old_idle = cfq_cfqq_idle_window(cfqq); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3340 | |
Corrado Zoccolo | 76280af | 2009-11-26 10:02:58 +0100 | [diff] [blame] | 3341 | if (cfqq->queued[0] + cfqq->queued[1] >= 4) |
| 3342 | cfq_mark_cfqq_deep(cfqq); |
| 3343 | |
Corrado Zoccolo | 749ef9f | 2010-09-20 15:24:50 +0200 | [diff] [blame] | 3344 | if (cfqq->next_rq && (cfqq->next_rq->cmd_flags & REQ_NOIDLE)) |
| 3345 | enable_idle = 0; |
Tejun Heo | f6e8d01 | 2012-03-05 13:15:26 -0800 | [diff] [blame] | 3346 | else if (!atomic_read(&cic->icq.ioc->active_ref) || |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 3347 | !cfqd->cfq_slice_idle || |
| 3348 | (!cfq_cfqq_deep(cfqq) && CFQQ_SEEKY(cfqq))) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3349 | enable_idle = 0; |
Shaohua Li | 383cd72 | 2011-07-12 14:24:35 +0200 | [diff] [blame] | 3350 | else if (sample_valid(cic->ttime.ttime_samples)) { |
| 3351 | if (cic->ttime.ttime_mean > cfqd->cfq_slice_idle) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3352 | enable_idle = 0; |
| 3353 | else |
| 3354 | enable_idle = 1; |
| 3355 | } |
| 3356 | |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 3357 | if (old_idle != enable_idle) { |
| 3358 | cfq_log_cfqq(cfqd, cfqq, "idle=%d", enable_idle); |
| 3359 | if (enable_idle) |
| 3360 | cfq_mark_cfqq_idle_window(cfqq); |
| 3361 | else |
| 3362 | cfq_clear_cfqq_idle_window(cfqq); |
| 3363 | } |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3364 | } |
| 3365 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3366 | /* |
| 3367 | * Check if new_cfqq should preempt the currently active queue. Return 0 for |
| 3368 | * no or if we aren't sure, a 1 will cause a preempt. |
| 3369 | */ |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 3370 | static bool |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3371 | cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq, |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 3372 | struct request *rq) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3373 | { |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 3374 | struct cfq_queue *cfqq; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3375 | |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 3376 | cfqq = cfqd->active_queue; |
| 3377 | if (!cfqq) |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 3378 | return false; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3379 | |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 3380 | if (cfq_class_idle(new_cfqq)) |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 3381 | return false; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3382 | |
| 3383 | if (cfq_class_idle(cfqq)) |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 3384 | return true; |
Jens Axboe | 1e3335d | 2007-02-14 19:59:49 +0100 | [diff] [blame] | 3385 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3386 | /* |
Divyesh Shah | 875feb6 | 2010-01-06 18:58:20 -0800 | [diff] [blame] | 3387 | * Don't allow a non-RT request to preempt an ongoing RT cfqq timeslice. |
| 3388 | */ |
| 3389 | if (cfq_class_rt(cfqq) && !cfq_class_rt(new_cfqq)) |
| 3390 | return false; |
| 3391 | |
| 3392 | /* |
Jens Axboe | 374f84a | 2006-07-23 01:42:19 +0200 | [diff] [blame] | 3393 | * if the new request is sync, but the currently running queue is |
| 3394 | * not, let the sync request have priority. |
| 3395 | */ |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 3396 | if (rq_is_sync(rq) && !cfq_cfqq_sync(cfqq)) |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 3397 | return true; |
Jens Axboe | 1e3335d | 2007-02-14 19:59:49 +0100 | [diff] [blame] | 3398 | |
Vivek Goyal | 8682e1f | 2009-12-03 12:59:50 -0500 | [diff] [blame] | 3399 | if (new_cfqq->cfqg != cfqq->cfqg) |
| 3400 | return false; |
| 3401 | |
| 3402 | if (cfq_slice_used(cfqq)) |
| 3403 | return true; |
| 3404 | |
| 3405 | /* Allow preemption only if we are idling on sync-noidle tree */ |
| 3406 | if (cfqd->serving_type == SYNC_NOIDLE_WORKLOAD && |
| 3407 | cfqq_type(new_cfqq) == SYNC_NOIDLE_WORKLOAD && |
| 3408 | new_cfqq->service_tree->count == 2 && |
| 3409 | RB_EMPTY_ROOT(&cfqq->sort_list)) |
| 3410 | return true; |
| 3411 | |
Jens Axboe | 374f84a | 2006-07-23 01:42:19 +0200 | [diff] [blame] | 3412 | /* |
Jens Axboe | b53d1ed | 2011-08-19 08:34:48 +0200 | [diff] [blame] | 3413 | * So both queues are sync. Let the new request get disk time if |
| 3414 | * it's a metadata request and the current queue is doing regular IO. |
| 3415 | */ |
Christoph Hellwig | 65299a3 | 2011-08-23 14:50:29 +0200 | [diff] [blame] | 3416 | if ((rq->cmd_flags & REQ_PRIO) && !cfqq->prio_pending) |
Jens Axboe | b53d1ed | 2011-08-19 08:34:48 +0200 | [diff] [blame] | 3417 | return true; |
| 3418 | |
| 3419 | /* |
Divyesh Shah | 3a9a3f6 | 2009-01-30 12:46:41 +0100 | [diff] [blame] | 3420 | * Allow an RT request to pre-empt an ongoing non-RT cfqq timeslice. |
| 3421 | */ |
| 3422 | if (cfq_class_rt(new_cfqq) && !cfq_class_rt(cfqq)) |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 3423 | return true; |
Divyesh Shah | 3a9a3f6 | 2009-01-30 12:46:41 +0100 | [diff] [blame] | 3424 | |
Shaohua Li | d2d59e1 | 2010-11-08 15:01:03 +0100 | [diff] [blame] | 3425 | /* An idle queue should not be idle now for some reason */ |
| 3426 | if (RB_EMPTY_ROOT(&cfqq->sort_list) && !cfq_should_idle(cfqd, cfqq)) |
| 3427 | return true; |
| 3428 | |
Jens Axboe | 1e3335d | 2007-02-14 19:59:49 +0100 | [diff] [blame] | 3429 | if (!cfqd->active_cic || !cfq_cfqq_wait_request(cfqq)) |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 3430 | return false; |
Jens Axboe | 1e3335d | 2007-02-14 19:59:49 +0100 | [diff] [blame] | 3431 | |
| 3432 | /* |
| 3433 | * if this request is as-good as one we would expect from the |
| 3434 | * current cfqq, let it preempt |
| 3435 | */ |
Shaohua Li | e9ce335 | 2010-03-19 08:03:04 +0100 | [diff] [blame] | 3436 | if (cfq_rq_close(cfqd, cfqq, rq)) |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 3437 | return true; |
Jens Axboe | 1e3335d | 2007-02-14 19:59:49 +0100 | [diff] [blame] | 3438 | |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 3439 | return false; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3440 | } |
| 3441 | |
| 3442 | /* |
| 3443 | * cfqq preempts the active queue. if we allowed preempt with no slice left, |
| 3444 | * let it have half of its nominal slice. |
| 3445 | */ |
| 3446 | static void cfq_preempt_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
| 3447 | { |
Shaohua Li | df0793a | 2012-01-19 09:20:09 +0100 | [diff] [blame] | 3448 | enum wl_type_t old_type = cfqq_type(cfqd->active_queue); |
| 3449 | |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 3450 | cfq_log_cfqq(cfqd, cfqq, "preempt"); |
Shaohua Li | df0793a | 2012-01-19 09:20:09 +0100 | [diff] [blame] | 3451 | cfq_slice_expired(cfqd, 1); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3452 | |
Jens Axboe | bf57225 | 2006-07-19 20:29:12 +0200 | [diff] [blame] | 3453 | /* |
Shaohua Li | f8ae6e3 | 2011-01-14 08:41:02 +0100 | [diff] [blame] | 3454 | * workload type is changed, don't save slice, otherwise preempt |
| 3455 | * doesn't happen |
| 3456 | */ |
Shaohua Li | df0793a | 2012-01-19 09:20:09 +0100 | [diff] [blame] | 3457 | if (old_type != cfqq_type(cfqq)) |
Shaohua Li | f8ae6e3 | 2011-01-14 08:41:02 +0100 | [diff] [blame] | 3458 | cfqq->cfqg->saved_workload_slice = 0; |
| 3459 | |
| 3460 | /* |
Jens Axboe | bf57225 | 2006-07-19 20:29:12 +0200 | [diff] [blame] | 3461 | * Put the new queue at the front of the of the current list, |
| 3462 | * so we know that it will be selected next. |
| 3463 | */ |
| 3464 | BUG_ON(!cfq_cfqq_on_rr(cfqq)); |
Jens Axboe | edd75ff | 2007-04-19 12:03:34 +0200 | [diff] [blame] | 3465 | |
| 3466 | cfq_service_tree_add(cfqd, cfqq, 1); |
Justin TerAvest | eda5e0c | 2011-03-22 21:26:49 +0100 | [diff] [blame] | 3467 | |
Justin TerAvest | 62a37f6 | 2011-03-23 08:25:44 +0100 | [diff] [blame] | 3468 | cfqq->slice_end = 0; |
| 3469 | cfq_mark_cfqq_slice_new(cfqq); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3470 | } |
| 3471 | |
| 3472 | /* |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 3473 | * Called when a new fs request (rq) is added (to cfqq). Check if there's |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3474 | * something we should do about it |
| 3475 | */ |
| 3476 | static void |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 3477 | cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, |
| 3478 | struct request *rq) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3479 | { |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 3480 | struct cfq_io_cq *cic = RQ_CIC(rq); |
Jens Axboe | 12e9fdd | 2006-06-01 10:09:56 +0200 | [diff] [blame] | 3481 | |
Aaron Carroll | 45333d5 | 2008-08-26 15:52:36 +0200 | [diff] [blame] | 3482 | cfqd->rq_queued++; |
Christoph Hellwig | 65299a3 | 2011-08-23 14:50:29 +0200 | [diff] [blame] | 3483 | if (rq->cmd_flags & REQ_PRIO) |
| 3484 | cfqq->prio_pending++; |
Jens Axboe | 374f84a | 2006-07-23 01:42:19 +0200 | [diff] [blame] | 3485 | |
Shaohua Li | 383cd72 | 2011-07-12 14:24:35 +0200 | [diff] [blame] | 3486 | cfq_update_io_thinktime(cfqd, cfqq, cic); |
Jeff Moyer | b2c18e1 | 2009-10-23 17:14:49 -0400 | [diff] [blame] | 3487 | cfq_update_io_seektime(cfqd, cfqq, rq); |
Jens Axboe | 9c2c38a | 2005-08-24 14:57:54 +0200 | [diff] [blame] | 3488 | cfq_update_idle_window(cfqd, cfqq, cic); |
| 3489 | |
Jeff Moyer | b2c18e1 | 2009-10-23 17:14:49 -0400 | [diff] [blame] | 3490 | cfqq->last_request_pos = blk_rq_pos(rq) + blk_rq_sectors(rq); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3491 | |
| 3492 | if (cfqq == cfqd->active_queue) { |
| 3493 | /* |
Jens Axboe | b029195 | 2009-04-07 11:38:31 +0200 | [diff] [blame] | 3494 | * Remember that we saw a request from this process, but |
| 3495 | * don't start queuing just yet. Otherwise we risk seeing lots |
| 3496 | * of tiny requests, because we disrupt the normal plugging |
Jens Axboe | d6ceb25 | 2009-04-14 14:18:16 +0200 | [diff] [blame] | 3497 | * and merging. If the request is already larger than a single |
| 3498 | * page, let it rip immediately. For that case we assume that |
Jens Axboe | 2d87072 | 2009-04-15 12:12:46 +0200 | [diff] [blame] | 3499 | * merging is already done. Ditto for a busy system that |
| 3500 | * has other work pending, don't risk delaying until the |
| 3501 | * idle timer unplug to continue working. |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3502 | */ |
Jens Axboe | d6ceb25 | 2009-04-14 14:18:16 +0200 | [diff] [blame] | 3503 | if (cfq_cfqq_wait_request(cfqq)) { |
Jens Axboe | 2d87072 | 2009-04-15 12:12:46 +0200 | [diff] [blame] | 3504 | if (blk_rq_bytes(rq) > PAGE_CACHE_SIZE || |
| 3505 | cfqd->busy_queues > 1) { |
Divyesh Shah | 812df48 | 2010-04-08 21:15:35 -0700 | [diff] [blame] | 3506 | cfq_del_timer(cfqd, cfqq); |
Gui Jianfeng | 554554f | 2009-12-10 09:38:39 +0100 | [diff] [blame] | 3507 | cfq_clear_cfqq_wait_request(cfqq); |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 3508 | __blk_run_queue(cfqd->queue); |
Divyesh Shah | a11cdaa | 2010-04-13 19:59:17 +0200 | [diff] [blame] | 3509 | } else { |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 3510 | cfqg_stats_update_idle_time(cfqq->cfqg); |
Vivek Goyal | bf791937 | 2009-12-03 12:59:37 -0500 | [diff] [blame] | 3511 | cfq_mark_cfqq_must_dispatch(cfqq); |
Divyesh Shah | a11cdaa | 2010-04-13 19:59:17 +0200 | [diff] [blame] | 3512 | } |
Jens Axboe | d6ceb25 | 2009-04-14 14:18:16 +0200 | [diff] [blame] | 3513 | } |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 3514 | } else if (cfq_should_preempt(cfqd, cfqq, rq)) { |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3515 | /* |
| 3516 | * not the active queue - expire current slice if it is |
| 3517 | * idle and has expired it's mean thinktime or this new queue |
Divyesh Shah | 3a9a3f6 | 2009-01-30 12:46:41 +0100 | [diff] [blame] | 3518 | * has some old slice time left and is of higher priority or |
| 3519 | * this new queue is RT and the current one is BE |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3520 | */ |
| 3521 | cfq_preempt_queue(cfqd, cfqq); |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 3522 | __blk_run_queue(cfqd->queue); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3523 | } |
| 3524 | } |
| 3525 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 3526 | static void cfq_insert_request(struct request_queue *q, struct request *rq) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3527 | { |
Jens Axboe | b4878f2 | 2005-10-20 16:42:29 +0200 | [diff] [blame] | 3528 | struct cfq_data *cfqd = q->elevator->elevator_data; |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 3529 | struct cfq_queue *cfqq = RQ_CFQQ(rq); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3530 | |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 3531 | cfq_log_cfqq(cfqd, cfqq, "insert_request"); |
Tejun Heo | abede6d | 2012-03-19 15:10:57 -0700 | [diff] [blame] | 3532 | cfq_init_prio_data(cfqq, RQ_CIC(rq)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3533 | |
Jens Axboe | 30996f4 | 2009-10-05 11:03:39 +0200 | [diff] [blame] | 3534 | rq_set_fifo_time(rq, jiffies + cfqd->cfq_fifo_expire[rq_is_sync(rq)]); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3535 | list_add_tail(&rq->queuelist, &cfqq->fifo); |
Corrado Zoccolo | aa6f6a3 | 2009-10-26 22:44:33 +0100 | [diff] [blame] | 3536 | cfq_add_rq_rb(rq); |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 3537 | cfqg_stats_update_io_add(RQ_CFQG(rq), cfqd->serving_group, |
| 3538 | rq->cmd_flags); |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 3539 | cfq_rq_enqueued(cfqd, cfqq, rq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3540 | } |
| 3541 | |
Aaron Carroll | 45333d5 | 2008-08-26 15:52:36 +0200 | [diff] [blame] | 3542 | /* |
| 3543 | * Update hw_tag based on peak queue depth over 50 samples under |
| 3544 | * sufficient load. |
| 3545 | */ |
| 3546 | static void cfq_update_hw_tag(struct cfq_data *cfqd) |
| 3547 | { |
Shaohua Li | 1a1238a | 2009-10-27 08:46:23 +0100 | [diff] [blame] | 3548 | struct cfq_queue *cfqq = cfqd->active_queue; |
| 3549 | |
Corrado Zoccolo | 53c583d | 2010-02-28 19:45:05 +0100 | [diff] [blame] | 3550 | if (cfqd->rq_in_driver > cfqd->hw_tag_est_depth) |
| 3551 | cfqd->hw_tag_est_depth = cfqd->rq_in_driver; |
Corrado Zoccolo | e459dd0 | 2009-11-26 10:02:57 +0100 | [diff] [blame] | 3552 | |
| 3553 | if (cfqd->hw_tag == 1) |
| 3554 | return; |
Aaron Carroll | 45333d5 | 2008-08-26 15:52:36 +0200 | [diff] [blame] | 3555 | |
| 3556 | if (cfqd->rq_queued <= CFQ_HW_QUEUE_MIN && |
Corrado Zoccolo | 53c583d | 2010-02-28 19:45:05 +0100 | [diff] [blame] | 3557 | cfqd->rq_in_driver <= CFQ_HW_QUEUE_MIN) |
Aaron Carroll | 45333d5 | 2008-08-26 15:52:36 +0200 | [diff] [blame] | 3558 | return; |
| 3559 | |
Shaohua Li | 1a1238a | 2009-10-27 08:46:23 +0100 | [diff] [blame] | 3560 | /* |
| 3561 | * If active queue hasn't enough requests and can idle, cfq might not |
| 3562 | * dispatch sufficient requests to hardware. Don't zero hw_tag in this |
| 3563 | * case |
| 3564 | */ |
| 3565 | if (cfqq && cfq_cfqq_idle_window(cfqq) && |
| 3566 | cfqq->dispatched + cfqq->queued[0] + cfqq->queued[1] < |
Corrado Zoccolo | 53c583d | 2010-02-28 19:45:05 +0100 | [diff] [blame] | 3567 | CFQ_HW_QUEUE_MIN && cfqd->rq_in_driver < CFQ_HW_QUEUE_MIN) |
Shaohua Li | 1a1238a | 2009-10-27 08:46:23 +0100 | [diff] [blame] | 3568 | return; |
| 3569 | |
Aaron Carroll | 45333d5 | 2008-08-26 15:52:36 +0200 | [diff] [blame] | 3570 | if (cfqd->hw_tag_samples++ < 50) |
| 3571 | return; |
| 3572 | |
Corrado Zoccolo | e459dd0 | 2009-11-26 10:02:57 +0100 | [diff] [blame] | 3573 | if (cfqd->hw_tag_est_depth >= CFQ_HW_QUEUE_MIN) |
Aaron Carroll | 45333d5 | 2008-08-26 15:52:36 +0200 | [diff] [blame] | 3574 | cfqd->hw_tag = 1; |
| 3575 | else |
| 3576 | cfqd->hw_tag = 0; |
Aaron Carroll | 45333d5 | 2008-08-26 15:52:36 +0200 | [diff] [blame] | 3577 | } |
| 3578 | |
Vivek Goyal | 7667aa0 | 2009-12-08 17:52:58 -0500 | [diff] [blame] | 3579 | static bool cfq_should_wait_busy(struct cfq_data *cfqd, struct cfq_queue *cfqq) |
| 3580 | { |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 3581 | struct cfq_io_cq *cic = cfqd->active_cic; |
Vivek Goyal | 7667aa0 | 2009-12-08 17:52:58 -0500 | [diff] [blame] | 3582 | |
Justin TerAvest | 02a8f01 | 2011-02-09 14:20:03 +0100 | [diff] [blame] | 3583 | /* If the queue already has requests, don't wait */ |
| 3584 | if (!RB_EMPTY_ROOT(&cfqq->sort_list)) |
| 3585 | return false; |
| 3586 | |
Vivek Goyal | 7667aa0 | 2009-12-08 17:52:58 -0500 | [diff] [blame] | 3587 | /* If there are other queues in the group, don't wait */ |
| 3588 | if (cfqq->cfqg->nr_cfqq > 1) |
| 3589 | return false; |
| 3590 | |
Shaohua Li | 7700fc4 | 2011-07-12 14:24:56 +0200 | [diff] [blame] | 3591 | /* the only queue in the group, but think time is big */ |
| 3592 | if (cfq_io_thinktime_big(cfqd, &cfqq->cfqg->ttime, true)) |
| 3593 | return false; |
| 3594 | |
Vivek Goyal | 7667aa0 | 2009-12-08 17:52:58 -0500 | [diff] [blame] | 3595 | if (cfq_slice_used(cfqq)) |
| 3596 | return true; |
| 3597 | |
| 3598 | /* if slice left is less than think time, wait busy */ |
Shaohua Li | 383cd72 | 2011-07-12 14:24:35 +0200 | [diff] [blame] | 3599 | if (cic && sample_valid(cic->ttime.ttime_samples) |
| 3600 | && (cfqq->slice_end - jiffies < cic->ttime.ttime_mean)) |
Vivek Goyal | 7667aa0 | 2009-12-08 17:52:58 -0500 | [diff] [blame] | 3601 | return true; |
| 3602 | |
| 3603 | /* |
| 3604 | * If think times is less than a jiffy than ttime_mean=0 and above |
| 3605 | * will not be true. It might happen that slice has not expired yet |
| 3606 | * but will expire soon (4-5 ns) during select_queue(). To cover the |
| 3607 | * case where think time is less than a jiffy, mark the queue wait |
| 3608 | * busy if only 1 jiffy is left in the slice. |
| 3609 | */ |
| 3610 | if (cfqq->slice_end - jiffies == 1) |
| 3611 | return true; |
| 3612 | |
| 3613 | return false; |
| 3614 | } |
| 3615 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 3616 | static void cfq_completed_request(struct request_queue *q, struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3617 | { |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 3618 | struct cfq_queue *cfqq = RQ_CFQQ(rq); |
Jens Axboe | b4878f2 | 2005-10-20 16:42:29 +0200 | [diff] [blame] | 3619 | struct cfq_data *cfqd = cfqq->cfqd; |
Jens Axboe | 5380a10 | 2006-07-13 12:37:56 +0200 | [diff] [blame] | 3620 | const int sync = rq_is_sync(rq); |
Jens Axboe | b4878f2 | 2005-10-20 16:42:29 +0200 | [diff] [blame] | 3621 | unsigned long now; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3622 | |
Jens Axboe | b4878f2 | 2005-10-20 16:42:29 +0200 | [diff] [blame] | 3623 | now = jiffies; |
Christoph Hellwig | 33659eb | 2010-08-07 18:17:56 +0200 | [diff] [blame] | 3624 | cfq_log_cfqq(cfqd, cfqq, "complete rqnoidle %d", |
| 3625 | !!(rq->cmd_flags & REQ_NOIDLE)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3626 | |
Aaron Carroll | 45333d5 | 2008-08-26 15:52:36 +0200 | [diff] [blame] | 3627 | cfq_update_hw_tag(cfqd); |
| 3628 | |
Corrado Zoccolo | 53c583d | 2010-02-28 19:45:05 +0100 | [diff] [blame] | 3629 | WARN_ON(!cfqd->rq_in_driver); |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 3630 | WARN_ON(!cfqq->dispatched); |
Corrado Zoccolo | 53c583d | 2010-02-28 19:45:05 +0100 | [diff] [blame] | 3631 | cfqd->rq_in_driver--; |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 3632 | cfqq->dispatched--; |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 3633 | (RQ_CFQG(rq))->dispatched--; |
Tejun Heo | 155fead | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 3634 | cfqg_stats_update_completion(cfqq->cfqg, rq_start_time_ns(rq), |
| 3635 | rq_io_start_time_ns(rq), rq->cmd_flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3636 | |
Corrado Zoccolo | 53c583d | 2010-02-28 19:45:05 +0100 | [diff] [blame] | 3637 | cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]--; |
Jens Axboe | 3ed9a29 | 2007-04-23 08:33:33 +0200 | [diff] [blame] | 3638 | |
Vivek Goyal | 365722b | 2009-10-03 15:21:27 +0200 | [diff] [blame] | 3639 | if (sync) { |
Shaohua Li | f5f2b6c | 2011-07-12 14:24:55 +0200 | [diff] [blame] | 3640 | struct cfq_rb_root *service_tree; |
| 3641 | |
Shaohua Li | 383cd72 | 2011-07-12 14:24:35 +0200 | [diff] [blame] | 3642 | RQ_CIC(rq)->ttime.last_end_request = now; |
Shaohua Li | f5f2b6c | 2011-07-12 14:24:55 +0200 | [diff] [blame] | 3643 | |
| 3644 | if (cfq_cfqq_on_rr(cfqq)) |
| 3645 | service_tree = cfqq->service_tree; |
| 3646 | else |
| 3647 | service_tree = service_tree_for(cfqq->cfqg, |
| 3648 | cfqq_prio(cfqq), cfqq_type(cfqq)); |
| 3649 | service_tree->ttime.last_end_request = now; |
Corrado Zoccolo | 573412b | 2009-12-06 11:48:52 +0100 | [diff] [blame] | 3650 | if (!time_after(rq->start_time + cfqd->cfq_fifo_expire[1], now)) |
| 3651 | cfqd->last_delayed_sync = now; |
Vivek Goyal | 365722b | 2009-10-03 15:21:27 +0200 | [diff] [blame] | 3652 | } |
Jens Axboe | caaa5f9 | 2006-06-16 11:23:00 +0200 | [diff] [blame] | 3653 | |
Shaohua Li | 7700fc4 | 2011-07-12 14:24:56 +0200 | [diff] [blame] | 3654 | #ifdef CONFIG_CFQ_GROUP_IOSCHED |
| 3655 | cfqq->cfqg->ttime.last_end_request = now; |
| 3656 | #endif |
| 3657 | |
Jens Axboe | caaa5f9 | 2006-06-16 11:23:00 +0200 | [diff] [blame] | 3658 | /* |
| 3659 | * If this is the active queue, check if it needs to be expired, |
| 3660 | * or if we want to idle in case it has no pending requests. |
| 3661 | */ |
| 3662 | if (cfqd->active_queue == cfqq) { |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 3663 | const bool cfqq_empty = RB_EMPTY_ROOT(&cfqq->sort_list); |
| 3664 | |
Jens Axboe | 44f7c16 | 2007-01-19 11:51:58 +1100 | [diff] [blame] | 3665 | if (cfq_cfqq_slice_new(cfqq)) { |
| 3666 | cfq_set_prio_slice(cfqd, cfqq); |
| 3667 | cfq_clear_cfqq_slice_new(cfqq); |
| 3668 | } |
Vivek Goyal | f75edf2 | 2009-12-03 12:59:53 -0500 | [diff] [blame] | 3669 | |
| 3670 | /* |
Vivek Goyal | 7667aa0 | 2009-12-08 17:52:58 -0500 | [diff] [blame] | 3671 | * Should we wait for next request to come in before we expire |
| 3672 | * the queue. |
Vivek Goyal | f75edf2 | 2009-12-03 12:59:53 -0500 | [diff] [blame] | 3673 | */ |
Vivek Goyal | 7667aa0 | 2009-12-08 17:52:58 -0500 | [diff] [blame] | 3674 | if (cfq_should_wait_busy(cfqd, cfqq)) { |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 3675 | unsigned long extend_sl = cfqd->cfq_slice_idle; |
| 3676 | if (!cfqd->cfq_slice_idle) |
| 3677 | extend_sl = cfqd->cfq_group_idle; |
| 3678 | cfqq->slice_end = jiffies + extend_sl; |
Vivek Goyal | f75edf2 | 2009-12-03 12:59:53 -0500 | [diff] [blame] | 3679 | cfq_mark_cfqq_wait_busy(cfqq); |
Divyesh Shah | b1ffe73 | 2010-03-25 15:45:03 +0100 | [diff] [blame] | 3680 | cfq_log_cfqq(cfqd, cfqq, "will busy wait"); |
Vivek Goyal | f75edf2 | 2009-12-03 12:59:53 -0500 | [diff] [blame] | 3681 | } |
| 3682 | |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 3683 | /* |
Corrado Zoccolo | 8e55063 | 2009-11-26 10:02:58 +0100 | [diff] [blame] | 3684 | * Idling is not enabled on: |
| 3685 | * - expired queues |
| 3686 | * - idle-priority queues |
| 3687 | * - async queues |
| 3688 | * - queues with still some requests queued |
| 3689 | * - when there is a close cooperator |
Jens Axboe | a36e71f | 2009-04-15 12:15:11 +0200 | [diff] [blame] | 3690 | */ |
Jens Axboe | 0871714 | 2008-01-28 11:38:15 +0100 | [diff] [blame] | 3691 | if (cfq_slice_used(cfqq) || cfq_class_idle(cfqq)) |
Vivek Goyal | e5ff082 | 2010-04-26 19:25:11 +0200 | [diff] [blame] | 3692 | cfq_slice_expired(cfqd, 1); |
Corrado Zoccolo | 8e55063 | 2009-11-26 10:02:58 +0100 | [diff] [blame] | 3693 | else if (sync && cfqq_empty && |
| 3694 | !cfq_close_cooperator(cfqd, cfqq)) { |
Corrado Zoccolo | 749ef9f | 2010-09-20 15:24:50 +0200 | [diff] [blame] | 3695 | cfq_arm_slice_timer(cfqd); |
Corrado Zoccolo | 8e55063 | 2009-11-26 10:02:58 +0100 | [diff] [blame] | 3696 | } |
Jens Axboe | caaa5f9 | 2006-06-16 11:23:00 +0200 | [diff] [blame] | 3697 | } |
Jens Axboe | 6d048f5 | 2007-04-25 12:44:27 +0200 | [diff] [blame] | 3698 | |
Corrado Zoccolo | 53c583d | 2010-02-28 19:45:05 +0100 | [diff] [blame] | 3699 | if (!cfqd->rq_in_driver) |
Jens Axboe | 23e018a | 2009-10-05 08:52:35 +0200 | [diff] [blame] | 3700 | cfq_schedule_dispatch(cfqd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3701 | } |
| 3702 | |
Jens Axboe | 89850f7 | 2006-07-22 16:48:31 +0200 | [diff] [blame] | 3703 | static inline int __cfq_may_queue(struct cfq_queue *cfqq) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3704 | { |
Jens Axboe | 1b379d8 | 2009-08-11 08:26:11 +0200 | [diff] [blame] | 3705 | if (cfq_cfqq_wait_request(cfqq) && !cfq_cfqq_must_alloc_slice(cfqq)) { |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 3706 | cfq_mark_cfqq_must_alloc_slice(cfqq); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3707 | return ELV_MQUEUE_MUST; |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 3708 | } |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3709 | |
| 3710 | return ELV_MQUEUE_MAY; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3711 | } |
| 3712 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 3713 | static int cfq_may_queue(struct request_queue *q, int rw) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3714 | { |
| 3715 | struct cfq_data *cfqd = q->elevator->elevator_data; |
| 3716 | struct task_struct *tsk = current; |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 3717 | struct cfq_io_cq *cic; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3718 | struct cfq_queue *cfqq; |
| 3719 | |
| 3720 | /* |
| 3721 | * don't force setup of a queue from here, as a call to may_queue |
| 3722 | * does not necessarily imply that a request actually will be queued. |
| 3723 | * so just lookup a possibly existing queue, or return 'may queue' |
| 3724 | * if that fails |
| 3725 | */ |
Jens Axboe | 4ac845a | 2008-01-24 08:44:49 +0100 | [diff] [blame] | 3726 | cic = cfq_cic_lookup(cfqd, tsk->io_context); |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 3727 | if (!cic) |
| 3728 | return ELV_MQUEUE_MAY; |
| 3729 | |
Jens Axboe | b0b78f8 | 2009-04-08 10:56:08 +0200 | [diff] [blame] | 3730 | cfqq = cic_to_cfqq(cic, rw_is_sync(rw)); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3731 | if (cfqq) { |
Tejun Heo | abede6d | 2012-03-19 15:10:57 -0700 | [diff] [blame] | 3732 | cfq_init_prio_data(cfqq, cic); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3733 | |
Jens Axboe | 89850f7 | 2006-07-22 16:48:31 +0200 | [diff] [blame] | 3734 | return __cfq_may_queue(cfqq); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3735 | } |
| 3736 | |
| 3737 | return ELV_MQUEUE_MAY; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3738 | } |
| 3739 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3740 | /* |
| 3741 | * queue lock held here |
| 3742 | */ |
Jens Axboe | bb37b94 | 2006-12-01 10:42:33 +0100 | [diff] [blame] | 3743 | static void cfq_put_request(struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3744 | { |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 3745 | struct cfq_queue *cfqq = RQ_CFQQ(rq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3746 | |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 3747 | if (cfqq) { |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3748 | const int rw = rq_data_dir(rq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3749 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3750 | BUG_ON(!cfqq->allocated[rw]); |
| 3751 | cfqq->allocated[rw]--; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3752 | |
Vivek Goyal | 7f1dc8a | 2010-04-21 17:44:16 +0200 | [diff] [blame] | 3753 | /* Put down rq reference on cfqg */ |
Tejun Heo | eb7d8c07 | 2012-03-23 14:02:53 +0100 | [diff] [blame] | 3754 | cfqg_put(RQ_CFQG(rq)); |
Tejun Heo | a612fdd | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 3755 | rq->elv.priv[0] = NULL; |
| 3756 | rq->elv.priv[1] = NULL; |
Vivek Goyal | 7f1dc8a | 2010-04-21 17:44:16 +0200 | [diff] [blame] | 3757 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3758 | cfq_put_queue(cfqq); |
| 3759 | } |
| 3760 | } |
| 3761 | |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 3762 | static struct cfq_queue * |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 3763 | cfq_merge_cfqqs(struct cfq_data *cfqd, struct cfq_io_cq *cic, |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 3764 | struct cfq_queue *cfqq) |
| 3765 | { |
| 3766 | cfq_log_cfqq(cfqd, cfqq, "merging with queue %p", cfqq->new_cfqq); |
| 3767 | cic_set_cfqq(cic, cfqq->new_cfqq, 1); |
Jeff Moyer | b3b6d04 | 2009-10-23 17:14:51 -0400 | [diff] [blame] | 3768 | cfq_mark_cfqq_coop(cfqq->new_cfqq); |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 3769 | cfq_put_queue(cfqq); |
| 3770 | return cic_to_cfqq(cic, 1); |
| 3771 | } |
| 3772 | |
Jeff Moyer | e6c5bc7 | 2009-10-23 17:14:52 -0400 | [diff] [blame] | 3773 | /* |
| 3774 | * Returns NULL if a new cfqq should be allocated, or the old cfqq if this |
| 3775 | * was the last process referring to said cfqq. |
| 3776 | */ |
| 3777 | static struct cfq_queue * |
Tejun Heo | c586980 | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 3778 | split_cfqq(struct cfq_io_cq *cic, struct cfq_queue *cfqq) |
Jeff Moyer | e6c5bc7 | 2009-10-23 17:14:52 -0400 | [diff] [blame] | 3779 | { |
| 3780 | if (cfqq_process_refs(cfqq) == 1) { |
Jeff Moyer | e6c5bc7 | 2009-10-23 17:14:52 -0400 | [diff] [blame] | 3781 | cfqq->pid = current->pid; |
| 3782 | cfq_clear_cfqq_coop(cfqq); |
Shaohua Li | ae54abe | 2010-02-05 13:11:45 +0100 | [diff] [blame] | 3783 | cfq_clear_cfqq_split_coop(cfqq); |
Jeff Moyer | e6c5bc7 | 2009-10-23 17:14:52 -0400 | [diff] [blame] | 3784 | return cfqq; |
| 3785 | } |
| 3786 | |
| 3787 | cic_set_cfqq(cic, NULL, 1); |
Shaohua Li | d02a2c0 | 2010-05-25 10:16:53 +0200 | [diff] [blame] | 3788 | |
| 3789 | cfq_put_cooperator(cfqq); |
| 3790 | |
Jeff Moyer | e6c5bc7 | 2009-10-23 17:14:52 -0400 | [diff] [blame] | 3791 | cfq_put_queue(cfqq); |
| 3792 | return NULL; |
| 3793 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3794 | /* |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3795 | * Allocate cfq data structures associated with this request. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3796 | */ |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3797 | static int |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 3798 | cfq_set_request(struct request_queue *q, struct request *rq, struct bio *bio, |
| 3799 | gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3800 | { |
| 3801 | struct cfq_data *cfqd = q->elevator->elevator_data; |
Tejun Heo | f1f8cc9 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 3802 | struct cfq_io_cq *cic = icq_to_cic(rq->elv.icq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3803 | const int rw = rq_data_dir(rq); |
Jens Axboe | a6151c3 | 2009-10-07 20:02:57 +0200 | [diff] [blame] | 3804 | const bool is_sync = rq_is_sync(rq); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3805 | struct cfq_queue *cfqq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3806 | |
| 3807 | might_sleep_if(gfp_mask & __GFP_WAIT); |
| 3808 | |
Tejun Heo | 216284c | 2011-12-14 00:33:38 +0100 | [diff] [blame] | 3809 | spin_lock_irq(q->queue_lock); |
Tejun Heo | f1f8cc9 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 3810 | |
Tejun Heo | 598971b | 2012-03-19 15:10:58 -0700 | [diff] [blame] | 3811 | check_ioprio_changed(cic, bio); |
| 3812 | check_blkcg_changed(cic, bio); |
Jeff Moyer | e6c5bc7 | 2009-10-23 17:14:52 -0400 | [diff] [blame] | 3813 | new_queue: |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 3814 | cfqq = cic_to_cfqq(cic, is_sync); |
Vivek Goyal | 32f2e80 | 2009-07-09 22:13:16 +0200 | [diff] [blame] | 3815 | if (!cfqq || cfqq == &cfqd->oom_cfqq) { |
Tejun Heo | abede6d | 2012-03-19 15:10:57 -0700 | [diff] [blame] | 3816 | cfqq = cfq_get_queue(cfqd, is_sync, cic, bio, gfp_mask); |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 3817 | cic_set_cfqq(cic, cfqq, is_sync); |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 3818 | } else { |
| 3819 | /* |
Jeff Moyer | e6c5bc7 | 2009-10-23 17:14:52 -0400 | [diff] [blame] | 3820 | * If the queue was seeky for too long, break it apart. |
| 3821 | */ |
Shaohua Li | ae54abe | 2010-02-05 13:11:45 +0100 | [diff] [blame] | 3822 | if (cfq_cfqq_coop(cfqq) && cfq_cfqq_split_coop(cfqq)) { |
Jeff Moyer | e6c5bc7 | 2009-10-23 17:14:52 -0400 | [diff] [blame] | 3823 | cfq_log_cfqq(cfqd, cfqq, "breaking apart cfqq"); |
| 3824 | cfqq = split_cfqq(cic, cfqq); |
| 3825 | if (!cfqq) |
| 3826 | goto new_queue; |
| 3827 | } |
| 3828 | |
| 3829 | /* |
Jeff Moyer | df5fe3e | 2009-10-23 17:14:50 -0400 | [diff] [blame] | 3830 | * Check to see if this queue is scheduled to merge with |
| 3831 | * another, closely cooperating queue. The merging of |
| 3832 | * queues happens here as it must be done in process context. |
| 3833 | * The reference on new_cfqq was taken in merge_cfqqs. |
| 3834 | */ |
| 3835 | if (cfqq->new_cfqq) |
| 3836 | cfqq = cfq_merge_cfqqs(cfqd, cic, cfqq); |
Vasily Tarasov | 91fac31 | 2007-04-25 12:29:51 +0200 | [diff] [blame] | 3837 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3838 | |
| 3839 | cfqq->allocated[rw]++; |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 3840 | |
Jens Axboe | 6fae9c2 | 2011-03-01 15:04:39 -0500 | [diff] [blame] | 3841 | cfqq->ref++; |
Tejun Heo | eb7d8c07 | 2012-03-23 14:02:53 +0100 | [diff] [blame] | 3842 | cfqg_get(cfqq->cfqg); |
Tejun Heo | a612fdd | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 3843 | rq->elv.priv[0] = cfqq; |
Tejun Heo | 1adaf3d | 2012-03-05 13:15:15 -0800 | [diff] [blame] | 3844 | rq->elv.priv[1] = cfqq->cfqg; |
Tejun Heo | 216284c | 2011-12-14 00:33:38 +0100 | [diff] [blame] | 3845 | spin_unlock_irq(q->queue_lock); |
Jens Axboe | 5e70537 | 2006-07-13 12:39:25 +0200 | [diff] [blame] | 3846 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3847 | } |
| 3848 | |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 3849 | static void cfq_kick_queue(struct work_struct *work) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3850 | { |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 3851 | struct cfq_data *cfqd = |
Jens Axboe | 23e018a | 2009-10-05 08:52:35 +0200 | [diff] [blame] | 3852 | container_of(work, struct cfq_data, unplug_work); |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 3853 | struct request_queue *q = cfqd->queue; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3854 | |
Jens Axboe | 40bb54d | 2009-04-15 12:11:10 +0200 | [diff] [blame] | 3855 | spin_lock_irq(q->queue_lock); |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 3856 | __blk_run_queue(cfqd->queue); |
Jens Axboe | 40bb54d | 2009-04-15 12:11:10 +0200 | [diff] [blame] | 3857 | spin_unlock_irq(q->queue_lock); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3858 | } |
| 3859 | |
| 3860 | /* |
| 3861 | * Timer running if the active_queue is currently idling inside its time slice |
| 3862 | */ |
| 3863 | static void cfq_idle_slice_timer(unsigned long data) |
| 3864 | { |
| 3865 | struct cfq_data *cfqd = (struct cfq_data *) data; |
| 3866 | struct cfq_queue *cfqq; |
| 3867 | unsigned long flags; |
Jens Axboe | 3c6bd2f | 2007-01-19 12:06:33 +1100 | [diff] [blame] | 3868 | int timed_out = 1; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3869 | |
Jens Axboe | 7b67913 | 2008-05-30 12:23:07 +0200 | [diff] [blame] | 3870 | cfq_log(cfqd, "idle timer fired"); |
| 3871 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3872 | spin_lock_irqsave(cfqd->queue->queue_lock, flags); |
| 3873 | |
Jens Axboe | fe094d9 | 2008-01-31 13:08:54 +0100 | [diff] [blame] | 3874 | cfqq = cfqd->active_queue; |
| 3875 | if (cfqq) { |
Jens Axboe | 3c6bd2f | 2007-01-19 12:06:33 +1100 | [diff] [blame] | 3876 | timed_out = 0; |
| 3877 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3878 | /* |
Jens Axboe | b029195 | 2009-04-07 11:38:31 +0200 | [diff] [blame] | 3879 | * We saw a request before the queue expired, let it through |
| 3880 | */ |
| 3881 | if (cfq_cfqq_must_dispatch(cfqq)) |
| 3882 | goto out_kick; |
| 3883 | |
| 3884 | /* |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3885 | * expired |
| 3886 | */ |
Jens Axboe | 44f7c16 | 2007-01-19 11:51:58 +1100 | [diff] [blame] | 3887 | if (cfq_slice_used(cfqq)) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3888 | goto expire; |
| 3889 | |
| 3890 | /* |
| 3891 | * only expire and reinvoke request handler, if there are |
| 3892 | * other queues with pending requests |
| 3893 | */ |
Jens Axboe | caaa5f9 | 2006-06-16 11:23:00 +0200 | [diff] [blame] | 3894 | if (!cfqd->busy_queues) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3895 | goto out_cont; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3896 | |
| 3897 | /* |
| 3898 | * not expired and it has a request pending, let it dispatch |
| 3899 | */ |
Jens Axboe | 75e5098 | 2009-04-07 08:56:14 +0200 | [diff] [blame] | 3900 | if (!RB_EMPTY_ROOT(&cfqq->sort_list)) |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3901 | goto out_kick; |
Corrado Zoccolo | 76280af | 2009-11-26 10:02:58 +0100 | [diff] [blame] | 3902 | |
| 3903 | /* |
| 3904 | * Queue depth flag is reset only when the idle didn't succeed |
| 3905 | */ |
| 3906 | cfq_clear_cfqq_deep(cfqq); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3907 | } |
| 3908 | expire: |
Vivek Goyal | e5ff082 | 2010-04-26 19:25:11 +0200 | [diff] [blame] | 3909 | cfq_slice_expired(cfqd, timed_out); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3910 | out_kick: |
Jens Axboe | 23e018a | 2009-10-05 08:52:35 +0200 | [diff] [blame] | 3911 | cfq_schedule_dispatch(cfqd); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3912 | out_cont: |
| 3913 | spin_unlock_irqrestore(cfqd->queue->queue_lock, flags); |
| 3914 | } |
| 3915 | |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 3916 | static void cfq_shutdown_timer_wq(struct cfq_data *cfqd) |
| 3917 | { |
| 3918 | del_timer_sync(&cfqd->idle_slice_timer); |
Jens Axboe | 23e018a | 2009-10-05 08:52:35 +0200 | [diff] [blame] | 3919 | cancel_work_sync(&cfqd->unplug_work); |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 3920 | } |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3921 | |
Vasily Tarasov | c2dea2d | 2007-07-20 10:06:38 +0200 | [diff] [blame] | 3922 | static void cfq_put_async_queues(struct cfq_data *cfqd) |
| 3923 | { |
| 3924 | int i; |
| 3925 | |
| 3926 | for (i = 0; i < IOPRIO_BE_NR; i++) { |
| 3927 | if (cfqd->async_cfqq[0][i]) |
| 3928 | cfq_put_queue(cfqd->async_cfqq[0][i]); |
| 3929 | if (cfqd->async_cfqq[1][i]) |
| 3930 | cfq_put_queue(cfqd->async_cfqq[1][i]); |
Vasily Tarasov | c2dea2d | 2007-07-20 10:06:38 +0200 | [diff] [blame] | 3931 | } |
Oleg Nesterov | 2389d1e | 2007-11-05 08:58:05 +0100 | [diff] [blame] | 3932 | |
| 3933 | if (cfqd->async_idle_cfqq) |
| 3934 | cfq_put_queue(cfqd->async_idle_cfqq); |
Vasily Tarasov | c2dea2d | 2007-07-20 10:06:38 +0200 | [diff] [blame] | 3935 | } |
| 3936 | |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 3937 | static void cfq_exit_queue(struct elevator_queue *e) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3938 | { |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3939 | struct cfq_data *cfqd = e->elevator_data; |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 3940 | struct request_queue *q = cfqd->queue; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 3941 | |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 3942 | cfq_shutdown_timer_wq(cfqd); |
Jens Axboe | e2d74ac | 2006-03-28 08:59:01 +0200 | [diff] [blame] | 3943 | |
Al Viro | d9ff418 | 2006-03-18 13:51:22 -0500 | [diff] [blame] | 3944 | spin_lock_irq(q->queue_lock); |
Jens Axboe | e2d74ac | 2006-03-28 08:59:01 +0200 | [diff] [blame] | 3945 | |
Al Viro | d9ff418 | 2006-03-18 13:51:22 -0500 | [diff] [blame] | 3946 | if (cfqd->active_queue) |
Vivek Goyal | e5ff082 | 2010-04-26 19:25:11 +0200 | [diff] [blame] | 3947 | __cfq_slice_expired(cfqd, cfqd->active_queue, 0); |
Jens Axboe | e2d74ac | 2006-03-28 08:59:01 +0200 | [diff] [blame] | 3948 | |
Vasily Tarasov | c2dea2d | 2007-07-20 10:06:38 +0200 | [diff] [blame] | 3949 | cfq_put_async_queues(cfqd); |
Tejun Heo | 03aa264 | 2012-03-05 13:15:19 -0800 | [diff] [blame] | 3950 | |
| 3951 | spin_unlock_irq(q->queue_lock); |
| 3952 | |
Al Viro | a90d742 | 2006-03-18 12:05:37 -0500 | [diff] [blame] | 3953 | cfq_shutdown_timer_wq(cfqd); |
| 3954 | |
Tejun Heo | ffea73f | 2012-06-04 10:02:29 +0200 | [diff] [blame] | 3955 | #ifdef CONFIG_CFQ_GROUP_IOSCHED |
| 3956 | blkcg_deactivate_policy(q, &blkcg_policy_cfq); |
| 3957 | #else |
Tejun Heo | f51b802 | 2012-03-05 13:15:05 -0800 | [diff] [blame] | 3958 | kfree(cfqd->root_group); |
Vivek Goyal | 2abae55 | 2011-05-23 10:02:19 +0200 | [diff] [blame] | 3959 | #endif |
Vivek Goyal | 56edf7d | 2011-05-19 15:38:22 -0400 | [diff] [blame] | 3960 | kfree(cfqd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3961 | } |
| 3962 | |
Tejun Heo | b2fab5a | 2012-03-05 13:14:57 -0800 | [diff] [blame] | 3963 | static int cfq_init_queue(struct request_queue *q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3964 | { |
| 3965 | struct cfq_data *cfqd; |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 3966 | struct blkcg_gq *blkg __maybe_unused; |
Tejun Heo | a2b1693 | 2012-04-13 13:11:33 -0700 | [diff] [blame] | 3967 | int i, ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3968 | |
Christoph Lameter | 94f6030 | 2007-07-17 04:03:29 -0700 | [diff] [blame] | 3969 | cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL | __GFP_ZERO, q->node); |
Tejun Heo | a73f730 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 3970 | if (!cfqd) |
Tejun Heo | b2fab5a | 2012-03-05 13:14:57 -0800 | [diff] [blame] | 3971 | return -ENOMEM; |
Konstantin Khlebnikov | 80b15c7 | 2010-05-20 23:21:41 +0400 | [diff] [blame] | 3972 | |
Tejun Heo | f51b802 | 2012-03-05 13:15:05 -0800 | [diff] [blame] | 3973 | cfqd->queue = q; |
| 3974 | q->elevator->elevator_data = cfqd; |
| 3975 | |
Vivek Goyal | 1fa8f6d | 2009-12-03 12:59:41 -0500 | [diff] [blame] | 3976 | /* Init root service tree */ |
| 3977 | cfqd->grp_service_tree = CFQ_RB_ROOT; |
| 3978 | |
Tejun Heo | f51b802 | 2012-03-05 13:15:05 -0800 | [diff] [blame] | 3979 | /* Init root group and prefer root group over other groups by default */ |
Vivek Goyal | 25fb516 | 2009-12-03 12:59:46 -0500 | [diff] [blame] | 3980 | #ifdef CONFIG_CFQ_GROUP_IOSCHED |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 3981 | ret = blkcg_activate_policy(q, &blkcg_policy_cfq); |
Tejun Heo | a2b1693 | 2012-04-13 13:11:33 -0700 | [diff] [blame] | 3982 | if (ret) |
| 3983 | goto out_free; |
Vivek Goyal | 5624a4e | 2011-05-19 15:38:28 -0400 | [diff] [blame] | 3984 | |
Tejun Heo | a2b1693 | 2012-04-13 13:11:33 -0700 | [diff] [blame] | 3985 | cfqd->root_group = blkg_to_cfqg(q->root_blkg); |
Tejun Heo | f51b802 | 2012-03-05 13:15:05 -0800 | [diff] [blame] | 3986 | #else |
Tejun Heo | a2b1693 | 2012-04-13 13:11:33 -0700 | [diff] [blame] | 3987 | ret = -ENOMEM; |
Tejun Heo | f51b802 | 2012-03-05 13:15:05 -0800 | [diff] [blame] | 3988 | cfqd->root_group = kzalloc_node(sizeof(*cfqd->root_group), |
| 3989 | GFP_KERNEL, cfqd->queue->node); |
Tejun Heo | a2b1693 | 2012-04-13 13:11:33 -0700 | [diff] [blame] | 3990 | if (!cfqd->root_group) |
| 3991 | goto out_free; |
Vivek Goyal | 5624a4e | 2011-05-19 15:38:28 -0400 | [diff] [blame] | 3992 | |
Tejun Heo | a2b1693 | 2012-04-13 13:11:33 -0700 | [diff] [blame] | 3993 | cfq_init_cfqg_base(cfqd->root_group); |
| 3994 | #endif |
Tejun Heo | 3381cb8 | 2012-04-01 14:38:44 -0700 | [diff] [blame] | 3995 | cfqd->root_group->weight = 2 * CFQ_WEIGHT_DEFAULT; |
Vivek Goyal | 5624a4e | 2011-05-19 15:38:28 -0400 | [diff] [blame] | 3996 | |
Jens Axboe | 26a2ac0 | 2009-04-23 12:13:27 +0200 | [diff] [blame] | 3997 | /* |
| 3998 | * Not strictly needed (since RB_ROOT just clears the node and we |
| 3999 | * zeroed cfqd on alloc), but better be safe in case someone decides |
| 4000 | * to add magic to the rb code |
| 4001 | */ |
| 4002 | for (i = 0; i < CFQ_PRIO_LISTS; i++) |
| 4003 | cfqd->prio_trees[i] = RB_ROOT; |
| 4004 | |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 4005 | /* |
| 4006 | * Our fallback cfqq if cfq_find_alloc_queue() runs into OOM issues. |
| 4007 | * Grab a permanent reference to it, so that the normal code flow |
Tejun Heo | f51b802 | 2012-03-05 13:15:05 -0800 | [diff] [blame] | 4008 | * will not attempt to free it. oom_cfqq is linked to root_group |
| 4009 | * but shouldn't hold a reference as it'll never be unlinked. Lose |
| 4010 | * the reference from linking right away. |
Jens Axboe | 6118b70 | 2009-06-30 09:34:12 +0200 | [diff] [blame] | 4011 | */ |
| 4012 | cfq_init_cfqq(cfqd, &cfqd->oom_cfqq, 1, 0); |
Shaohua Li | 30d7b94 | 2011-01-07 08:46:59 +0100 | [diff] [blame] | 4013 | cfqd->oom_cfqq.ref++; |
Tejun Heo | 1adaf3d | 2012-03-05 13:15:15 -0800 | [diff] [blame] | 4014 | |
| 4015 | spin_lock_irq(q->queue_lock); |
Tejun Heo | f51b802 | 2012-03-05 13:15:05 -0800 | [diff] [blame] | 4016 | cfq_link_cfqq_cfqg(&cfqd->oom_cfqq, cfqd->root_group); |
Tejun Heo | eb7d8c07 | 2012-03-23 14:02:53 +0100 | [diff] [blame] | 4017 | cfqg_put(cfqd->root_group); |
Tejun Heo | 1adaf3d | 2012-03-05 13:15:15 -0800 | [diff] [blame] | 4018 | spin_unlock_irq(q->queue_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4019 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 4020 | init_timer(&cfqd->idle_slice_timer); |
| 4021 | cfqd->idle_slice_timer.function = cfq_idle_slice_timer; |
| 4022 | cfqd->idle_slice_timer.data = (unsigned long) cfqd; |
| 4023 | |
Jens Axboe | 23e018a | 2009-10-05 08:52:35 +0200 | [diff] [blame] | 4024 | INIT_WORK(&cfqd->unplug_work, cfq_kick_queue); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 4025 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4026 | cfqd->cfq_quantum = cfq_quantum; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 4027 | cfqd->cfq_fifo_expire[0] = cfq_fifo_expire[0]; |
| 4028 | cfqd->cfq_fifo_expire[1] = cfq_fifo_expire[1]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4029 | cfqd->cfq_back_max = cfq_back_max; |
| 4030 | cfqd->cfq_back_penalty = cfq_back_penalty; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 4031 | cfqd->cfq_slice[0] = cfq_slice_async; |
| 4032 | cfqd->cfq_slice[1] = cfq_slice_sync; |
Tao Ma | 5bf14c0 | 2012-04-01 14:33:39 -0700 | [diff] [blame] | 4033 | cfqd->cfq_target_latency = cfq_target_latency; |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 4034 | cfqd->cfq_slice_async_rq = cfq_slice_async_rq; |
| 4035 | cfqd->cfq_slice_idle = cfq_slice_idle; |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 4036 | cfqd->cfq_group_idle = cfq_group_idle; |
Jens Axboe | 963b72f | 2009-10-03 19:42:18 +0200 | [diff] [blame] | 4037 | cfqd->cfq_latency = 1; |
Corrado Zoccolo | e459dd0 | 2009-11-26 10:02:57 +0100 | [diff] [blame] | 4038 | cfqd->hw_tag = -1; |
Corrado Zoccolo | edc7113 | 2009-12-09 20:56:04 +0100 | [diff] [blame] | 4039 | /* |
| 4040 | * we optimistically start assuming sync ops weren't delayed in last |
| 4041 | * second, in order to have larger depth for async operations. |
| 4042 | */ |
Corrado Zoccolo | 573412b | 2009-12-06 11:48:52 +0100 | [diff] [blame] | 4043 | cfqd->last_delayed_sync = jiffies - HZ; |
Tejun Heo | b2fab5a | 2012-03-05 13:14:57 -0800 | [diff] [blame] | 4044 | return 0; |
Tejun Heo | a2b1693 | 2012-04-13 13:11:33 -0700 | [diff] [blame] | 4045 | |
| 4046 | out_free: |
| 4047 | kfree(cfqd); |
| 4048 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4049 | } |
| 4050 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4051 | /* |
| 4052 | * sysfs parts below --> |
| 4053 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4054 | static ssize_t |
| 4055 | cfq_var_show(unsigned int var, char *page) |
| 4056 | { |
| 4057 | return sprintf(page, "%d\n", var); |
| 4058 | } |
| 4059 | |
| 4060 | static ssize_t |
| 4061 | cfq_var_store(unsigned int *var, const char *page, size_t count) |
| 4062 | { |
| 4063 | char *p = (char *) page; |
| 4064 | |
| 4065 | *var = simple_strtoul(p, &p, 10); |
| 4066 | return count; |
| 4067 | } |
| 4068 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4069 | #define SHOW_FUNCTION(__FUNC, __VAR, __CONV) \ |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 4070 | static ssize_t __FUNC(struct elevator_queue *e, char *page) \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4071 | { \ |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 4072 | struct cfq_data *cfqd = e->elevator_data; \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4073 | unsigned int __data = __VAR; \ |
| 4074 | if (__CONV) \ |
| 4075 | __data = jiffies_to_msecs(__data); \ |
| 4076 | return cfq_var_show(__data, (page)); \ |
| 4077 | } |
| 4078 | SHOW_FUNCTION(cfq_quantum_show, cfqd->cfq_quantum, 0); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 4079 | SHOW_FUNCTION(cfq_fifo_expire_sync_show, cfqd->cfq_fifo_expire[1], 1); |
| 4080 | SHOW_FUNCTION(cfq_fifo_expire_async_show, cfqd->cfq_fifo_expire[0], 1); |
Al Viro | e572ec7 | 2006-03-18 22:27:18 -0500 | [diff] [blame] | 4081 | SHOW_FUNCTION(cfq_back_seek_max_show, cfqd->cfq_back_max, 0); |
| 4082 | SHOW_FUNCTION(cfq_back_seek_penalty_show, cfqd->cfq_back_penalty, 0); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 4083 | SHOW_FUNCTION(cfq_slice_idle_show, cfqd->cfq_slice_idle, 1); |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 4084 | SHOW_FUNCTION(cfq_group_idle_show, cfqd->cfq_group_idle, 1); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 4085 | SHOW_FUNCTION(cfq_slice_sync_show, cfqd->cfq_slice[1], 1); |
| 4086 | SHOW_FUNCTION(cfq_slice_async_show, cfqd->cfq_slice[0], 1); |
| 4087 | SHOW_FUNCTION(cfq_slice_async_rq_show, cfqd->cfq_slice_async_rq, 0); |
Jens Axboe | 963b72f | 2009-10-03 19:42:18 +0200 | [diff] [blame] | 4088 | SHOW_FUNCTION(cfq_low_latency_show, cfqd->cfq_latency, 0); |
Tao Ma | 5bf14c0 | 2012-04-01 14:33:39 -0700 | [diff] [blame] | 4089 | SHOW_FUNCTION(cfq_target_latency_show, cfqd->cfq_target_latency, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4090 | #undef SHOW_FUNCTION |
| 4091 | |
| 4092 | #define STORE_FUNCTION(__FUNC, __PTR, MIN, MAX, __CONV) \ |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 4093 | static ssize_t __FUNC(struct elevator_queue *e, const char *page, size_t count) \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4094 | { \ |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 4095 | struct cfq_data *cfqd = e->elevator_data; \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4096 | unsigned int __data; \ |
| 4097 | int ret = cfq_var_store(&__data, (page), count); \ |
| 4098 | if (__data < (MIN)) \ |
| 4099 | __data = (MIN); \ |
| 4100 | else if (__data > (MAX)) \ |
| 4101 | __data = (MAX); \ |
| 4102 | if (__CONV) \ |
| 4103 | *(__PTR) = msecs_to_jiffies(__data); \ |
| 4104 | else \ |
| 4105 | *(__PTR) = __data; \ |
| 4106 | return ret; \ |
| 4107 | } |
| 4108 | STORE_FUNCTION(cfq_quantum_store, &cfqd->cfq_quantum, 1, UINT_MAX, 0); |
Jens Axboe | fe094d9 | 2008-01-31 13:08:54 +0100 | [diff] [blame] | 4109 | STORE_FUNCTION(cfq_fifo_expire_sync_store, &cfqd->cfq_fifo_expire[1], 1, |
| 4110 | UINT_MAX, 1); |
| 4111 | STORE_FUNCTION(cfq_fifo_expire_async_store, &cfqd->cfq_fifo_expire[0], 1, |
| 4112 | UINT_MAX, 1); |
Al Viro | e572ec7 | 2006-03-18 22:27:18 -0500 | [diff] [blame] | 4113 | STORE_FUNCTION(cfq_back_seek_max_store, &cfqd->cfq_back_max, 0, UINT_MAX, 0); |
Jens Axboe | fe094d9 | 2008-01-31 13:08:54 +0100 | [diff] [blame] | 4114 | STORE_FUNCTION(cfq_back_seek_penalty_store, &cfqd->cfq_back_penalty, 1, |
| 4115 | UINT_MAX, 0); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 4116 | STORE_FUNCTION(cfq_slice_idle_store, &cfqd->cfq_slice_idle, 0, UINT_MAX, 1); |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 4117 | STORE_FUNCTION(cfq_group_idle_store, &cfqd->cfq_group_idle, 0, UINT_MAX, 1); |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 4118 | STORE_FUNCTION(cfq_slice_sync_store, &cfqd->cfq_slice[1], 1, UINT_MAX, 1); |
| 4119 | STORE_FUNCTION(cfq_slice_async_store, &cfqd->cfq_slice[0], 1, UINT_MAX, 1); |
Jens Axboe | fe094d9 | 2008-01-31 13:08:54 +0100 | [diff] [blame] | 4120 | STORE_FUNCTION(cfq_slice_async_rq_store, &cfqd->cfq_slice_async_rq, 1, |
| 4121 | UINT_MAX, 0); |
Jens Axboe | 963b72f | 2009-10-03 19:42:18 +0200 | [diff] [blame] | 4122 | STORE_FUNCTION(cfq_low_latency_store, &cfqd->cfq_latency, 0, 1, 0); |
Tao Ma | 5bf14c0 | 2012-04-01 14:33:39 -0700 | [diff] [blame] | 4123 | STORE_FUNCTION(cfq_target_latency_store, &cfqd->cfq_target_latency, 1, UINT_MAX, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4124 | #undef STORE_FUNCTION |
| 4125 | |
Al Viro | e572ec7 | 2006-03-18 22:27:18 -0500 | [diff] [blame] | 4126 | #define CFQ_ATTR(name) \ |
| 4127 | __ATTR(name, S_IRUGO|S_IWUSR, cfq_##name##_show, cfq_##name##_store) |
Jens Axboe | 3b18152 | 2005-06-27 10:56:24 +0200 | [diff] [blame] | 4128 | |
Al Viro | e572ec7 | 2006-03-18 22:27:18 -0500 | [diff] [blame] | 4129 | static struct elv_fs_entry cfq_attrs[] = { |
| 4130 | CFQ_ATTR(quantum), |
Al Viro | e572ec7 | 2006-03-18 22:27:18 -0500 | [diff] [blame] | 4131 | CFQ_ATTR(fifo_expire_sync), |
| 4132 | CFQ_ATTR(fifo_expire_async), |
| 4133 | CFQ_ATTR(back_seek_max), |
| 4134 | CFQ_ATTR(back_seek_penalty), |
| 4135 | CFQ_ATTR(slice_sync), |
| 4136 | CFQ_ATTR(slice_async), |
| 4137 | CFQ_ATTR(slice_async_rq), |
| 4138 | CFQ_ATTR(slice_idle), |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 4139 | CFQ_ATTR(group_idle), |
Jens Axboe | 963b72f | 2009-10-03 19:42:18 +0200 | [diff] [blame] | 4140 | CFQ_ATTR(low_latency), |
Tao Ma | 5bf14c0 | 2012-04-01 14:33:39 -0700 | [diff] [blame] | 4141 | CFQ_ATTR(target_latency), |
Al Viro | e572ec7 | 2006-03-18 22:27:18 -0500 | [diff] [blame] | 4142 | __ATTR_NULL |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4143 | }; |
| 4144 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4145 | static struct elevator_type iosched_cfq = { |
| 4146 | .ops = { |
| 4147 | .elevator_merge_fn = cfq_merge, |
| 4148 | .elevator_merged_fn = cfq_merged_request, |
| 4149 | .elevator_merge_req_fn = cfq_merged_requests, |
Jens Axboe | da77526 | 2006-12-20 11:04:12 +0100 | [diff] [blame] | 4150 | .elevator_allow_merge_fn = cfq_allow_merge, |
Divyesh Shah | 812d402 | 2010-04-08 21:14:23 -0700 | [diff] [blame] | 4151 | .elevator_bio_merged_fn = cfq_bio_merged, |
Jens Axboe | b4878f2 | 2005-10-20 16:42:29 +0200 | [diff] [blame] | 4152 | .elevator_dispatch_fn = cfq_dispatch_requests, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4153 | .elevator_add_req_fn = cfq_insert_request, |
Jens Axboe | b4878f2 | 2005-10-20 16:42:29 +0200 | [diff] [blame] | 4154 | .elevator_activate_req_fn = cfq_activate_request, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4155 | .elevator_deactivate_req_fn = cfq_deactivate_request, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4156 | .elevator_completed_req_fn = cfq_completed_request, |
Jens Axboe | 21183b0 | 2006-07-13 12:33:14 +0200 | [diff] [blame] | 4157 | .elevator_former_req_fn = elv_rb_former_request, |
| 4158 | .elevator_latter_req_fn = elv_rb_latter_request, |
Tejun Heo | 9b84cac | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 4159 | .elevator_init_icq_fn = cfq_init_icq, |
Tejun Heo | 7e5a879 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 4160 | .elevator_exit_icq_fn = cfq_exit_icq, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4161 | .elevator_set_req_fn = cfq_set_request, |
| 4162 | .elevator_put_req_fn = cfq_put_request, |
| 4163 | .elevator_may_queue_fn = cfq_may_queue, |
| 4164 | .elevator_init_fn = cfq_init_queue, |
| 4165 | .elevator_exit_fn = cfq_exit_queue, |
| 4166 | }, |
Tejun Heo | 3d3c237 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 4167 | .icq_size = sizeof(struct cfq_io_cq), |
| 4168 | .icq_align = __alignof__(struct cfq_io_cq), |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 4169 | .elevator_attrs = cfq_attrs, |
Tejun Heo | 3d3c237 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 4170 | .elevator_name = "cfq", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4171 | .elevator_owner = THIS_MODULE, |
| 4172 | }; |
| 4173 | |
Vivek Goyal | 3e25206 | 2009-12-04 10:36:42 -0500 | [diff] [blame] | 4174 | #ifdef CONFIG_CFQ_GROUP_IOSCHED |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 4175 | static struct blkcg_policy blkcg_policy_cfq = { |
Tejun Heo | f9fcc2d | 2012-04-16 13:57:27 -0700 | [diff] [blame] | 4176 | .pd_size = sizeof(struct cfq_group), |
| 4177 | .cftypes = cfq_blkcg_files, |
| 4178 | |
| 4179 | .pd_init_fn = cfq_pd_init, |
| 4180 | .pd_reset_stats_fn = cfq_pd_reset_stats, |
Vivek Goyal | 3e25206 | 2009-12-04 10:36:42 -0500 | [diff] [blame] | 4181 | }; |
Vivek Goyal | 3e25206 | 2009-12-04 10:36:42 -0500 | [diff] [blame] | 4182 | #endif |
| 4183 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4184 | static int __init cfq_init(void) |
| 4185 | { |
Tejun Heo | 3d3c237 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 4186 | int ret; |
| 4187 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 4188 | /* |
| 4189 | * could be 0 on HZ < 1000 setups |
| 4190 | */ |
| 4191 | if (!cfq_slice_async) |
| 4192 | cfq_slice_async = 1; |
| 4193 | if (!cfq_slice_idle) |
| 4194 | cfq_slice_idle = 1; |
| 4195 | |
Vivek Goyal | 80bdf0c | 2010-08-23 12:24:26 +0200 | [diff] [blame] | 4196 | #ifdef CONFIG_CFQ_GROUP_IOSCHED |
| 4197 | if (!cfq_group_idle) |
| 4198 | cfq_group_idle = 1; |
Tejun Heo | 8bd435b | 2012-04-13 13:11:28 -0700 | [diff] [blame] | 4199 | |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 4200 | ret = blkcg_policy_register(&blkcg_policy_cfq); |
Tejun Heo | 8bd435b | 2012-04-13 13:11:28 -0700 | [diff] [blame] | 4201 | if (ret) |
| 4202 | return ret; |
Tejun Heo | ffea73f | 2012-06-04 10:02:29 +0200 | [diff] [blame] | 4203 | #else |
| 4204 | cfq_group_idle = 0; |
| 4205 | #endif |
Tejun Heo | 8bd435b | 2012-04-13 13:11:28 -0700 | [diff] [blame] | 4206 | |
Tejun Heo | fd79495 | 2012-06-04 10:01:38 +0200 | [diff] [blame] | 4207 | ret = -ENOMEM; |
Tejun Heo | 3d3c237 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 4208 | cfq_pool = KMEM_CACHE(cfq_queue, 0); |
| 4209 | if (!cfq_pool) |
Tejun Heo | 8bd435b | 2012-04-13 13:11:28 -0700 | [diff] [blame] | 4210 | goto err_pol_unreg; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4211 | |
Tejun Heo | 3d3c237 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 4212 | ret = elv_register(&iosched_cfq); |
Tejun Heo | 8bd435b | 2012-04-13 13:11:28 -0700 | [diff] [blame] | 4213 | if (ret) |
| 4214 | goto err_free_pool; |
Tejun Heo | 3d3c237 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 4215 | |
Adrian Bunk | 2fdd82b | 2007-12-12 18:51:56 +0100 | [diff] [blame] | 4216 | return 0; |
Tejun Heo | 8bd435b | 2012-04-13 13:11:28 -0700 | [diff] [blame] | 4217 | |
| 4218 | err_free_pool: |
| 4219 | kmem_cache_destroy(cfq_pool); |
| 4220 | err_pol_unreg: |
Tejun Heo | ffea73f | 2012-06-04 10:02:29 +0200 | [diff] [blame] | 4221 | #ifdef CONFIG_CFQ_GROUP_IOSCHED |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 4222 | blkcg_policy_unregister(&blkcg_policy_cfq); |
Tejun Heo | ffea73f | 2012-06-04 10:02:29 +0200 | [diff] [blame] | 4223 | #endif |
Tejun Heo | 8bd435b | 2012-04-13 13:11:28 -0700 | [diff] [blame] | 4224 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4225 | } |
| 4226 | |
| 4227 | static void __exit cfq_exit(void) |
| 4228 | { |
Tejun Heo | ffea73f | 2012-06-04 10:02:29 +0200 | [diff] [blame] | 4229 | #ifdef CONFIG_CFQ_GROUP_IOSCHED |
Tejun Heo | 3c79839 | 2012-04-16 13:57:25 -0700 | [diff] [blame] | 4230 | blkcg_policy_unregister(&blkcg_policy_cfq); |
Tejun Heo | ffea73f | 2012-06-04 10:02:29 +0200 | [diff] [blame] | 4231 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4232 | elv_unregister(&iosched_cfq); |
Tejun Heo | 3d3c237 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 4233 | kmem_cache_destroy(cfq_pool); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4234 | } |
| 4235 | |
| 4236 | module_init(cfq_init); |
| 4237 | module_exit(cfq_exit); |
| 4238 | |
| 4239 | MODULE_AUTHOR("Jens Axboe"); |
| 4240 | MODULE_LICENSE("GPL"); |
| 4241 | MODULE_DESCRIPTION("Completely Fair Queueing IO scheduler"); |