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 | * Block device elevator/IO-scheduler. |
| 3 | * |
| 4 | * Copyright (C) 2000 Andrea Arcangeli <andrea@suse.de> SuSE |
| 5 | * |
Jens Axboe | 0fe2347 | 2006-09-04 15:41:16 +0200 | [diff] [blame] | 6 | * 30042000 Jens Axboe <axboe@kernel.dk> : |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 7 | * |
| 8 | * Split the elevator a bit so that it is possible to choose a different |
| 9 | * one or even write a new "plug in". There are three pieces: |
| 10 | * - elevator_fn, inserts a new request in the queue list |
| 11 | * - elevator_merge_fn, decides whether a new buffer can be merged with |
| 12 | * an existing request |
| 13 | * - elevator_dequeue_fn, called when a request is taken off the active list |
| 14 | * |
| 15 | * 20082000 Dave Jones <davej@suse.de> : |
| 16 | * Removed tests for max-bomb-segments, which was breaking elvtune |
| 17 | * when run without -bN |
| 18 | * |
| 19 | * Jens: |
| 20 | * - Rework again to work with bio instead of buffer_heads |
| 21 | * - loose bi_dev comparisons, partition handling is right now |
| 22 | * - completely modularize elevator setup and teardown |
| 23 | * |
| 24 | */ |
| 25 | #include <linux/kernel.h> |
| 26 | #include <linux/fs.h> |
| 27 | #include <linux/blkdev.h> |
| 28 | #include <linux/elevator.h> |
| 29 | #include <linux/bio.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | #include <linux/module.h> |
| 31 | #include <linux/slab.h> |
| 32 | #include <linux/init.h> |
| 33 | #include <linux/compiler.h> |
Jens Axboe | 2056a78 | 2006-03-23 20:00:26 +0100 | [diff] [blame] | 34 | #include <linux/blktrace_api.h> |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 35 | #include <linux/hash.h> |
Jens Axboe | 0835da6 | 2008-08-26 09:15:47 +0200 | [diff] [blame] | 36 | #include <linux/uaccess.h> |
Lin Ming | c815881 | 2013-03-23 11:42:27 +0800 | [diff] [blame] | 37 | #include <linux/pm_runtime.h> |
Tejun Heo | eea8f41 | 2015-05-22 17:13:17 -0400 | [diff] [blame] | 38 | #include <linux/blk-cgroup.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | |
Li Zefan | 5578213 | 2009-06-09 13:43:05 +0800 | [diff] [blame] | 40 | #include <trace/events/block.h> |
| 41 | |
Jens Axboe | 242f9dc | 2008-09-14 05:55:09 -0700 | [diff] [blame] | 42 | #include "blk.h" |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 43 | #include "blk-mq-sched.h" |
Jan Kara | 8330cdb | 2017-04-19 11:33:27 +0200 | [diff] [blame] | 44 | #include "blk-wbt.h" |
Jens Axboe | 242f9dc | 2008-09-14 05:55:09 -0700 | [diff] [blame] | 45 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | static DEFINE_SPINLOCK(elv_list_lock); |
| 47 | static LIST_HEAD(elv_list); |
| 48 | |
| 49 | /* |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 50 | * Merge hash stuff. |
| 51 | */ |
Tejun Heo | 83096eb | 2009-05-07 22:24:39 +0900 | [diff] [blame] | 52 | #define rq_hash_key(rq) (blk_rq_pos(rq) + blk_rq_sectors(rq)) |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 53 | |
| 54 | /* |
Jens Axboe | da77526 | 2006-12-20 11:04:12 +0100 | [diff] [blame] | 55 | * Query io scheduler to see if the current process issuing bio may be |
| 56 | * merged with rq. |
| 57 | */ |
Tahsin Erdogan | 72ef799 | 2016-07-07 11:48:22 -0700 | [diff] [blame] | 58 | static int elv_iosched_allow_bio_merge(struct request *rq, struct bio *bio) |
Jens Axboe | da77526 | 2006-12-20 11:04:12 +0100 | [diff] [blame] | 59 | { |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 60 | struct request_queue *q = rq->q; |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 61 | struct elevator_queue *e = q->elevator; |
Jens Axboe | da77526 | 2006-12-20 11:04:12 +0100 | [diff] [blame] | 62 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 63 | if (e->uses_mq && e->type->ops.mq.allow_merge) |
| 64 | return e->type->ops.mq.allow_merge(q, rq, bio); |
| 65 | else if (!e->uses_mq && e->type->ops.sq.elevator_allow_bio_merge_fn) |
Jens Axboe | c51ca6c | 2016-12-10 15:13:59 -0700 | [diff] [blame] | 66 | return e->type->ops.sq.elevator_allow_bio_merge_fn(q, rq, bio); |
Jens Axboe | da77526 | 2006-12-20 11:04:12 +0100 | [diff] [blame] | 67 | |
| 68 | return 1; |
| 69 | } |
| 70 | |
| 71 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 72 | * can we safely merge with this request? |
| 73 | */ |
Tahsin Erdogan | 72ef799 | 2016-07-07 11:48:22 -0700 | [diff] [blame] | 74 | bool elv_bio_merge_ok(struct request *rq, struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 75 | { |
Tejun Heo | 050c8ea | 2012-02-08 09:19:38 +0100 | [diff] [blame] | 76 | if (!blk_rq_merge_ok(rq, bio)) |
Tahsin Erdogan | 72ef799 | 2016-07-07 11:48:22 -0700 | [diff] [blame] | 77 | return false; |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 78 | |
Tahsin Erdogan | 72ef799 | 2016-07-07 11:48:22 -0700 | [diff] [blame] | 79 | if (!elv_iosched_allow_bio_merge(rq, bio)) |
| 80 | return false; |
Jens Axboe | da77526 | 2006-12-20 11:04:12 +0100 | [diff] [blame] | 81 | |
Tahsin Erdogan | 72ef799 | 2016-07-07 11:48:22 -0700 | [diff] [blame] | 82 | return true; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 83 | } |
Tahsin Erdogan | 72ef799 | 2016-07-07 11:48:22 -0700 | [diff] [blame] | 84 | EXPORT_SYMBOL(elv_bio_merge_ok); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 85 | |
Jens Axboe | 8ac0d9a | 2017-10-25 12:35:02 -0600 | [diff] [blame] | 86 | static bool elevator_match(const struct elevator_type *e, const char *name) |
| 87 | { |
| 88 | if (!strcmp(e->elevator_name, name)) |
| 89 | return true; |
| 90 | if (e->elevator_alias && !strcmp(e->elevator_alias, name)) |
| 91 | return true; |
| 92 | |
| 93 | return false; |
| 94 | } |
| 95 | |
Jens Axboe | 2527d99 | 2017-10-25 12:33:42 -0600 | [diff] [blame] | 96 | /* |
| 97 | * Return scheduler with name 'name' and with matching 'mq capability |
| 98 | */ |
| 99 | static struct elevator_type *elevator_find(const char *name, bool mq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 100 | { |
Vasily Tarasov | a22b169 | 2006-10-11 09:24:27 +0200 | [diff] [blame] | 101 | struct elevator_type *e; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 102 | |
Matthias Kaehlcke | 70cee26 | 2007-07-10 12:26:24 +0200 | [diff] [blame] | 103 | list_for_each_entry(e, &elv_list, list) { |
Jens Axboe | 8ac0d9a | 2017-10-25 12:35:02 -0600 | [diff] [blame] | 104 | if (elevator_match(e, name) && (mq == e->uses_mq)) |
Vasily Tarasov | a22b169 | 2006-10-11 09:24:27 +0200 | [diff] [blame] | 105 | return e; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | |
Vasily Tarasov | a22b169 | 2006-10-11 09:24:27 +0200 | [diff] [blame] | 108 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 109 | } |
| 110 | |
| 111 | static void elevator_put(struct elevator_type *e) |
| 112 | { |
| 113 | module_put(e->elevator_owner); |
| 114 | } |
| 115 | |
Jens Axboe | 2527d99 | 2017-10-25 12:33:42 -0600 | [diff] [blame] | 116 | static struct elevator_type *elevator_get(struct request_queue *q, |
| 117 | const char *name, bool try_loading) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 118 | { |
Tejun Heo | 2824bc93 | 2005-10-20 10:56:41 +0200 | [diff] [blame] | 119 | struct elevator_type *e; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | |
Jens Axboe | 2a12dcd | 2007-04-26 14:41:53 +0200 | [diff] [blame] | 121 | spin_lock(&elv_list_lock); |
Tejun Heo | 2824bc93 | 2005-10-20 10:56:41 +0200 | [diff] [blame] | 122 | |
Jens Axboe | 2527d99 | 2017-10-25 12:33:42 -0600 | [diff] [blame] | 123 | e = elevator_find(name, q->mq_ops != NULL); |
Tejun Heo | 21c3c5d | 2013-01-22 16:48:03 -0800 | [diff] [blame] | 124 | if (!e && try_loading) { |
Jens Axboe | e164094 | 2008-02-19 10:20:37 +0100 | [diff] [blame] | 125 | spin_unlock(&elv_list_lock); |
Kees Cook | 490b94b | 2011-05-05 18:02:12 -0600 | [diff] [blame] | 126 | request_module("%s-iosched", name); |
Jens Axboe | e164094 | 2008-02-19 10:20:37 +0100 | [diff] [blame] | 127 | spin_lock(&elv_list_lock); |
Jens Axboe | 2527d99 | 2017-10-25 12:33:42 -0600 | [diff] [blame] | 128 | e = elevator_find(name, q->mq_ops != NULL); |
Jens Axboe | e164094 | 2008-02-19 10:20:37 +0100 | [diff] [blame] | 129 | } |
| 130 | |
Tejun Heo | 2824bc93 | 2005-10-20 10:56:41 +0200 | [diff] [blame] | 131 | if (e && !try_module_get(e->elevator_owner)) |
| 132 | e = NULL; |
| 133 | |
Jens Axboe | 2a12dcd | 2007-04-26 14:41:53 +0200 | [diff] [blame] | 134 | spin_unlock(&elv_list_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | return e; |
| 136 | } |
| 137 | |
Wang Sheng-Hui | 484fc25 | 2011-09-08 12:32:14 +0200 | [diff] [blame] | 138 | static char chosen_elevator[ELV_NAME_MAX]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | |
Nate Diller | 5f00397 | 2006-01-24 10:07:58 +0100 | [diff] [blame] | 140 | static int __init elevator_setup(char *str) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | { |
Chuck Ebbert | 752a3b7 | 2006-01-16 09:47:37 +0100 | [diff] [blame] | 142 | /* |
| 143 | * Be backwards-compatible with previous kernels, so users |
| 144 | * won't get the wrong elevator. |
| 145 | */ |
Jens Axboe | 492af63 | 2009-10-03 09:37:51 +0200 | [diff] [blame] | 146 | strncpy(chosen_elevator, str, sizeof(chosen_elevator) - 1); |
OGAWA Hirofumi | 9b41046 | 2006-03-31 02:30:33 -0800 | [diff] [blame] | 147 | return 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 148 | } |
| 149 | |
| 150 | __setup("elevator=", elevator_setup); |
| 151 | |
Tejun Heo | bb813f4 | 2013-01-18 14:05:56 -0800 | [diff] [blame] | 152 | /* called during boot to load the elevator chosen by the elevator param */ |
| 153 | void __init load_default_elevator_module(void) |
| 154 | { |
| 155 | struct elevator_type *e; |
| 156 | |
| 157 | if (!chosen_elevator[0]) |
| 158 | return; |
| 159 | |
Jens Axboe | 2527d99 | 2017-10-25 12:33:42 -0600 | [diff] [blame] | 160 | /* |
| 161 | * Boot parameter is deprecated, we haven't supported that for MQ. |
| 162 | * Only look for non-mq schedulers from here. |
| 163 | */ |
Tejun Heo | bb813f4 | 2013-01-18 14:05:56 -0800 | [diff] [blame] | 164 | spin_lock(&elv_list_lock); |
Jens Axboe | 2527d99 | 2017-10-25 12:33:42 -0600 | [diff] [blame] | 165 | e = elevator_find(chosen_elevator, false); |
Tejun Heo | bb813f4 | 2013-01-18 14:05:56 -0800 | [diff] [blame] | 166 | spin_unlock(&elv_list_lock); |
| 167 | |
| 168 | if (!e) |
| 169 | request_module("%s-iosched", chosen_elevator); |
| 170 | } |
| 171 | |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 172 | static struct kobj_type elv_ktype; |
| 173 | |
Jianpeng Ma | d50235b | 2013-07-03 13:25:24 +0200 | [diff] [blame] | 174 | struct elevator_queue *elevator_alloc(struct request_queue *q, |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 175 | struct elevator_type *e) |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 176 | { |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 177 | struct elevator_queue *eq; |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 178 | |
Joe Perches | c1b511e | 2013-08-29 15:21:42 -0700 | [diff] [blame] | 179 | eq = kzalloc_node(sizeof(*eq), GFP_KERNEL, q->node); |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 180 | if (unlikely(!eq)) |
Chao Yu | 8406a4d | 2015-04-23 10:47:44 -0600 | [diff] [blame] | 181 | return NULL; |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 182 | |
Tejun Heo | 22f746e | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 183 | eq->type = e; |
Greg Kroah-Hartman | f9cb074 | 2007-12-17 23:05:35 -0700 | [diff] [blame] | 184 | kobject_init(&eq->kobj, &elv_ktype); |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 185 | mutex_init(&eq->sysfs_lock); |
Sasha Levin | 242d98f | 2012-12-17 10:01:27 -0500 | [diff] [blame] | 186 | hash_init(eq->hash); |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 187 | eq->uses_mq = e->uses_mq; |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 188 | |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 189 | return eq; |
| 190 | } |
Jianpeng Ma | d50235b | 2013-07-03 13:25:24 +0200 | [diff] [blame] | 191 | EXPORT_SYMBOL(elevator_alloc); |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 192 | |
| 193 | static void elevator_release(struct kobject *kobj) |
| 194 | { |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 195 | struct elevator_queue *e; |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 196 | |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 197 | e = container_of(kobj, struct elevator_queue, kobj); |
Tejun Heo | 22f746e | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 198 | elevator_put(e->type); |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 199 | kfree(e); |
| 200 | } |
| 201 | |
Christoph Hellwig | 131d08e | 2018-05-31 19:11:40 +0200 | [diff] [blame^] | 202 | /* |
| 203 | * Use the default elevator specified by config boot param for non-mq devices, |
| 204 | * or by config option. Don't try to load modules as we could be running off |
| 205 | * async and request_module() isn't allowed from async. |
| 206 | */ |
Christoph Hellwig | ddb7253 | 2018-05-31 19:11:38 +0200 | [diff] [blame] | 207 | int elevator_init(struct request_queue *q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 208 | { |
| 209 | struct elevator_type *e = NULL; |
Christoph Hellwig | acddf3b | 2018-05-31 19:11:39 +0200 | [diff] [blame] | 210 | int err = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 211 | |
Tomoki Sekiyama | eb1c160 | 2013-10-15 16:42:16 -0600 | [diff] [blame] | 212 | /* |
| 213 | * q->sysfs_lock must be held to provide mutual exclusion between |
| 214 | * elevator_switch() and here. |
| 215 | */ |
Christoph Hellwig | acddf3b | 2018-05-31 19:11:39 +0200 | [diff] [blame] | 216 | mutex_lock(&q->sysfs_lock); |
Mike Snitzer | 1abec4f | 2010-05-25 13:15:15 -0400 | [diff] [blame] | 217 | if (unlikely(q->elevator)) |
Christoph Hellwig | acddf3b | 2018-05-31 19:11:39 +0200 | [diff] [blame] | 218 | goto out_unlock; |
Mike Snitzer | 1abec4f | 2010-05-25 13:15:15 -0400 | [diff] [blame] | 219 | |
Christoph Hellwig | 131d08e | 2018-05-31 19:11:40 +0200 | [diff] [blame^] | 220 | if (*chosen_elevator) { |
Jens Axboe | 2527d99 | 2017-10-25 12:33:42 -0600 | [diff] [blame] | 221 | e = elevator_get(q, chosen_elevator, false); |
Jens Axboe | 4eb166d | 2008-02-01 00:37:27 +0100 | [diff] [blame] | 222 | if (!e) |
| 223 | printk(KERN_ERR "I/O scheduler %s not found\n", |
| 224 | chosen_elevator); |
| 225 | } |
Nate Diller | 248d5ca | 2006-01-24 10:09:14 +0100 | [diff] [blame] | 226 | |
Christoph Hellwig | 131d08e | 2018-05-31 19:11:40 +0200 | [diff] [blame^] | 227 | if (!e) |
| 228 | e = elevator_get(q, CONFIG_DEFAULT_IOSCHED, false); |
Jens Axboe | 4eb166d | 2008-02-01 00:37:27 +0100 | [diff] [blame] | 229 | if (!e) { |
Christoph Hellwig | 131d08e | 2018-05-31 19:11:40 +0200 | [diff] [blame^] | 230 | printk(KERN_ERR |
| 231 | "Default I/O scheduler not found. Using noop.\n"); |
| 232 | e = elevator_get(q, "noop", false); |
Nate Diller | 5f00397 | 2006-01-24 10:07:58 +0100 | [diff] [blame] | 233 | } |
| 234 | |
Christoph Hellwig | 131d08e | 2018-05-31 19:11:40 +0200 | [diff] [blame^] | 235 | err = e->ops.sq.elevator_init_fn(q, e); |
Omar Sandoval | 6917ff0 | 2017-04-05 12:01:30 -0700 | [diff] [blame] | 236 | if (err) |
Sudip Mukherjee | d32f6b5 | 2014-10-23 22:16:48 +0530 | [diff] [blame] | 237 | elevator_put(e); |
Christoph Hellwig | acddf3b | 2018-05-31 19:11:39 +0200 | [diff] [blame] | 238 | out_unlock: |
| 239 | mutex_unlock(&q->sysfs_lock); |
Sudip Mukherjee | d32f6b5 | 2014-10-23 22:16:48 +0530 | [diff] [blame] | 240 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 241 | } |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 242 | |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 243 | void elevator_exit(struct request_queue *q, struct elevator_queue *e) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | { |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 245 | mutex_lock(&e->sysfs_lock); |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 246 | if (e->uses_mq && e->type->ops.mq.exit_sched) |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 247 | blk_mq_exit_sched(q, e); |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 248 | else if (!e->uses_mq && e->type->ops.sq.elevator_exit_fn) |
Jens Axboe | c51ca6c | 2016-12-10 15:13:59 -0700 | [diff] [blame] | 249 | e->type->ops.sq.elevator_exit_fn(e); |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 250 | mutex_unlock(&e->sysfs_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 251 | |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 252 | kobject_put(&e->kobj); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 253 | } |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 254 | |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 255 | static inline void __elv_rqhash_del(struct request *rq) |
| 256 | { |
Sasha Levin | 242d98f | 2012-12-17 10:01:27 -0500 | [diff] [blame] | 257 | hash_del(&rq->hash); |
Christoph Hellwig | e806402 | 2016-10-20 15:12:13 +0200 | [diff] [blame] | 258 | rq->rq_flags &= ~RQF_HASHED; |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 259 | } |
| 260 | |
Jens Axboe | 70b3ea0 | 2016-12-07 08:43:31 -0700 | [diff] [blame] | 261 | void elv_rqhash_del(struct request_queue *q, struct request *rq) |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 262 | { |
| 263 | if (ELV_ON_HASH(rq)) |
| 264 | __elv_rqhash_del(rq); |
| 265 | } |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 266 | EXPORT_SYMBOL_GPL(elv_rqhash_del); |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 267 | |
Jens Axboe | 70b3ea0 | 2016-12-07 08:43:31 -0700 | [diff] [blame] | 268 | void elv_rqhash_add(struct request_queue *q, struct request *rq) |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 269 | { |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 270 | struct elevator_queue *e = q->elevator; |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 271 | |
| 272 | BUG_ON(ELV_ON_HASH(rq)); |
Sasha Levin | 242d98f | 2012-12-17 10:01:27 -0500 | [diff] [blame] | 273 | hash_add(e->hash, &rq->hash, rq_hash_key(rq)); |
Christoph Hellwig | e806402 | 2016-10-20 15:12:13 +0200 | [diff] [blame] | 274 | rq->rq_flags |= RQF_HASHED; |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 275 | } |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 276 | EXPORT_SYMBOL_GPL(elv_rqhash_add); |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 277 | |
Jens Axboe | 70b3ea0 | 2016-12-07 08:43:31 -0700 | [diff] [blame] | 278 | void elv_rqhash_reposition(struct request_queue *q, struct request *rq) |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 279 | { |
| 280 | __elv_rqhash_del(rq); |
| 281 | elv_rqhash_add(q, rq); |
| 282 | } |
| 283 | |
Jens Axboe | 70b3ea0 | 2016-12-07 08:43:31 -0700 | [diff] [blame] | 284 | struct request *elv_rqhash_find(struct request_queue *q, sector_t offset) |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 285 | { |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 286 | struct elevator_queue *e = q->elevator; |
Sasha Levin | b67bfe0 | 2013-02-27 17:06:00 -0800 | [diff] [blame] | 287 | struct hlist_node *next; |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 288 | struct request *rq; |
| 289 | |
Linus Torvalds | ee89f81 | 2013-02-28 12:52:24 -0800 | [diff] [blame] | 290 | hash_for_each_possible_safe(e->hash, rq, next, hash, offset) { |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 291 | BUG_ON(!ELV_ON_HASH(rq)); |
| 292 | |
| 293 | if (unlikely(!rq_mergeable(rq))) { |
| 294 | __elv_rqhash_del(rq); |
| 295 | continue; |
| 296 | } |
| 297 | |
| 298 | if (rq_hash_key(rq) == offset) |
| 299 | return rq; |
| 300 | } |
| 301 | |
| 302 | return NULL; |
| 303 | } |
| 304 | |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 305 | /* |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 306 | * RB-tree support functions for inserting/lookup/removal of requests |
| 307 | * in a sorted RB tree. |
| 308 | */ |
Jeff Moyer | 796d511 | 2011-06-02 21:19:05 +0200 | [diff] [blame] | 309 | void elv_rb_add(struct rb_root *root, struct request *rq) |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 310 | { |
| 311 | struct rb_node **p = &root->rb_node; |
| 312 | struct rb_node *parent = NULL; |
| 313 | struct request *__rq; |
| 314 | |
| 315 | while (*p) { |
| 316 | parent = *p; |
| 317 | __rq = rb_entry(parent, struct request, rb_node); |
| 318 | |
Tejun Heo | 83096eb | 2009-05-07 22:24:39 +0900 | [diff] [blame] | 319 | if (blk_rq_pos(rq) < blk_rq_pos(__rq)) |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 320 | p = &(*p)->rb_left; |
Jeff Moyer | 796d511 | 2011-06-02 21:19:05 +0200 | [diff] [blame] | 321 | else if (blk_rq_pos(rq) >= blk_rq_pos(__rq)) |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 322 | p = &(*p)->rb_right; |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 323 | } |
| 324 | |
| 325 | rb_link_node(&rq->rb_node, parent, p); |
| 326 | rb_insert_color(&rq->rb_node, root); |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 327 | } |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 328 | EXPORT_SYMBOL(elv_rb_add); |
| 329 | |
| 330 | void elv_rb_del(struct rb_root *root, struct request *rq) |
| 331 | { |
| 332 | BUG_ON(RB_EMPTY_NODE(&rq->rb_node)); |
| 333 | rb_erase(&rq->rb_node, root); |
| 334 | RB_CLEAR_NODE(&rq->rb_node); |
| 335 | } |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 336 | EXPORT_SYMBOL(elv_rb_del); |
| 337 | |
| 338 | struct request *elv_rb_find(struct rb_root *root, sector_t sector) |
| 339 | { |
| 340 | struct rb_node *n = root->rb_node; |
| 341 | struct request *rq; |
| 342 | |
| 343 | while (n) { |
| 344 | rq = rb_entry(n, struct request, rb_node); |
| 345 | |
Tejun Heo | 83096eb | 2009-05-07 22:24:39 +0900 | [diff] [blame] | 346 | if (sector < blk_rq_pos(rq)) |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 347 | n = n->rb_left; |
Tejun Heo | 83096eb | 2009-05-07 22:24:39 +0900 | [diff] [blame] | 348 | else if (sector > blk_rq_pos(rq)) |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 349 | n = n->rb_right; |
| 350 | else |
| 351 | return rq; |
| 352 | } |
| 353 | |
| 354 | return NULL; |
| 355 | } |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 356 | EXPORT_SYMBOL(elv_rb_find); |
| 357 | |
| 358 | /* |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 359 | * Insert rq into dispatch queue of q. Queue lock must be held on |
Uwe Kleine-König | dbe7f76 | 2007-10-20 01:55:04 +0200 | [diff] [blame] | 360 | * entry. rq is sort instead into the dispatch queue. To be used by |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 361 | * specific elevators. |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 362 | */ |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 363 | void elv_dispatch_sort(struct request_queue *q, struct request *rq) |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 364 | { |
| 365 | sector_t boundary; |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 366 | struct list_head *entry; |
| 367 | |
Tejun Heo | 06b8624 | 2005-10-20 16:46:23 +0200 | [diff] [blame] | 368 | if (q->last_merge == rq) |
| 369 | q->last_merge = NULL; |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 370 | |
| 371 | elv_rqhash_del(q, rq); |
| 372 | |
Tejun Heo | 15853af | 2005-11-10 08:52:05 +0100 | [diff] [blame] | 373 | q->nr_sorted--; |
Tejun Heo | 06b8624 | 2005-10-20 16:46:23 +0200 | [diff] [blame] | 374 | |
Jens Axboe | 1b47f53 | 2005-10-20 16:37:00 +0200 | [diff] [blame] | 375 | boundary = q->end_sector; |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 376 | list_for_each_prev(entry, &q->queue_head) { |
| 377 | struct request *pos = list_entry_rq(entry); |
| 378 | |
Adrian Hunter | 7afafc8 | 2016-08-16 10:59:35 +0300 | [diff] [blame] | 379 | if (req_op(rq) != req_op(pos)) |
David Woodhouse | e17fc0a | 2008-08-09 16:42:20 +0100 | [diff] [blame] | 380 | break; |
Jens Axboe | 783660b | 2007-01-19 11:27:47 +1100 | [diff] [blame] | 381 | if (rq_data_dir(rq) != rq_data_dir(pos)) |
| 382 | break; |
Christoph Hellwig | e806402 | 2016-10-20 15:12:13 +0200 | [diff] [blame] | 383 | if (pos->rq_flags & (RQF_STARTED | RQF_SOFTBARRIER)) |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 384 | break; |
Tejun Heo | 83096eb | 2009-05-07 22:24:39 +0900 | [diff] [blame] | 385 | if (blk_rq_pos(rq) >= boundary) { |
| 386 | if (blk_rq_pos(pos) < boundary) |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 387 | continue; |
| 388 | } else { |
Tejun Heo | 83096eb | 2009-05-07 22:24:39 +0900 | [diff] [blame] | 389 | if (blk_rq_pos(pos) >= boundary) |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 390 | break; |
| 391 | } |
Tejun Heo | 83096eb | 2009-05-07 22:24:39 +0900 | [diff] [blame] | 392 | if (blk_rq_pos(rq) >= blk_rq_pos(pos)) |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 393 | break; |
| 394 | } |
| 395 | |
| 396 | list_add(&rq->queuelist, entry); |
| 397 | } |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 398 | EXPORT_SYMBOL(elv_dispatch_sort); |
| 399 | |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 400 | /* |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 401 | * Insert rq into dispatch queue of q. Queue lock must be held on |
| 402 | * entry. rq is added to the back of the dispatch queue. To be used by |
| 403 | * specific elevators. |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 404 | */ |
| 405 | void elv_dispatch_add_tail(struct request_queue *q, struct request *rq) |
| 406 | { |
| 407 | if (q->last_merge == rq) |
| 408 | q->last_merge = NULL; |
| 409 | |
| 410 | elv_rqhash_del(q, rq); |
| 411 | |
| 412 | q->nr_sorted--; |
| 413 | |
| 414 | q->end_sector = rq_end_sector(rq); |
| 415 | q->boundary_rq = rq; |
| 416 | list_add_tail(&rq->queuelist, &q->queue_head); |
| 417 | } |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 418 | EXPORT_SYMBOL(elv_dispatch_add_tail); |
| 419 | |
Christoph Hellwig | 34fe7c0 | 2017-02-08 14:46:48 +0100 | [diff] [blame] | 420 | enum elv_merge elv_merge(struct request_queue *q, struct request **req, |
| 421 | struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 422 | { |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 423 | struct elevator_queue *e = q->elevator; |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 424 | struct request *__rq; |
Tejun Heo | 06b8624 | 2005-10-20 16:46:23 +0200 | [diff] [blame] | 425 | |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 426 | /* |
Alan D. Brunelle | 488991e | 2010-01-29 09:04:08 +0100 | [diff] [blame] | 427 | * Levels of merges: |
| 428 | * nomerges: No merges at all attempted |
| 429 | * noxmerges: Only simple one-hit cache try |
| 430 | * merges: All merge tries attempted |
| 431 | */ |
Ming Lei | 7460d38 | 2015-10-20 23:13:55 +0800 | [diff] [blame] | 432 | if (blk_queue_nomerges(q) || !bio_mergeable(bio)) |
Alan D. Brunelle | 488991e | 2010-01-29 09:04:08 +0100 | [diff] [blame] | 433 | return ELEVATOR_NO_MERGE; |
| 434 | |
| 435 | /* |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 436 | * First try one-hit cache. |
| 437 | */ |
Tahsin Erdogan | 72ef799 | 2016-07-07 11:48:22 -0700 | [diff] [blame] | 438 | if (q->last_merge && elv_bio_merge_ok(q->last_merge, bio)) { |
Christoph Hellwig | 34fe7c0 | 2017-02-08 14:46:48 +0100 | [diff] [blame] | 439 | enum elv_merge ret = blk_try_merge(q->last_merge, bio); |
| 440 | |
Tejun Heo | 06b8624 | 2005-10-20 16:46:23 +0200 | [diff] [blame] | 441 | if (ret != ELEVATOR_NO_MERGE) { |
| 442 | *req = q->last_merge; |
| 443 | return ret; |
| 444 | } |
| 445 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 446 | |
Alan D. Brunelle | 488991e | 2010-01-29 09:04:08 +0100 | [diff] [blame] | 447 | if (blk_queue_noxmerges(q)) |
Alan D. Brunelle | ac9fafa | 2008-04-29 14:44:19 +0200 | [diff] [blame] | 448 | return ELEVATOR_NO_MERGE; |
| 449 | |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 450 | /* |
| 451 | * See if our hash lookup can find a potential backmerge. |
| 452 | */ |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 453 | __rq = elv_rqhash_find(q, bio->bi_iter.bi_sector); |
Tahsin Erdogan | 72ef799 | 2016-07-07 11:48:22 -0700 | [diff] [blame] | 454 | if (__rq && elv_bio_merge_ok(__rq, bio)) { |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 455 | *req = __rq; |
| 456 | return ELEVATOR_BACK_MERGE; |
| 457 | } |
| 458 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 459 | if (e->uses_mq && e->type->ops.mq.request_merge) |
| 460 | return e->type->ops.mq.request_merge(q, req, bio); |
| 461 | else if (!e->uses_mq && e->type->ops.sq.elevator_merge_fn) |
Jens Axboe | c51ca6c | 2016-12-10 15:13:59 -0700 | [diff] [blame] | 462 | return e->type->ops.sq.elevator_merge_fn(q, req, bio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 463 | |
| 464 | return ELEVATOR_NO_MERGE; |
| 465 | } |
| 466 | |
Jens Axboe | 5e84ea3 | 2011-03-21 10:14:27 +0100 | [diff] [blame] | 467 | /* |
| 468 | * Attempt to do an insertion back merge. Only check for the case where |
| 469 | * we can append 'rq' to an existing request, so we can throw 'rq' away |
| 470 | * afterwards. |
| 471 | * |
| 472 | * Returns true if we merged, false otherwise |
| 473 | */ |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 474 | bool elv_attempt_insert_merge(struct request_queue *q, struct request *rq) |
Jens Axboe | 5e84ea3 | 2011-03-21 10:14:27 +0100 | [diff] [blame] | 475 | { |
| 476 | struct request *__rq; |
Shaohua Li | bee0393 | 2012-11-09 08:44:27 +0100 | [diff] [blame] | 477 | bool ret; |
Jens Axboe | 5e84ea3 | 2011-03-21 10:14:27 +0100 | [diff] [blame] | 478 | |
| 479 | if (blk_queue_nomerges(q)) |
| 480 | return false; |
| 481 | |
| 482 | /* |
| 483 | * First try one-hit cache. |
| 484 | */ |
| 485 | if (q->last_merge && blk_attempt_req_merge(q, q->last_merge, rq)) |
| 486 | return true; |
| 487 | |
| 488 | if (blk_queue_noxmerges(q)) |
| 489 | return false; |
| 490 | |
Shaohua Li | bee0393 | 2012-11-09 08:44:27 +0100 | [diff] [blame] | 491 | ret = false; |
Jens Axboe | 5e84ea3 | 2011-03-21 10:14:27 +0100 | [diff] [blame] | 492 | /* |
| 493 | * See if our hash lookup can find a potential backmerge. |
| 494 | */ |
Shaohua Li | bee0393 | 2012-11-09 08:44:27 +0100 | [diff] [blame] | 495 | while (1) { |
| 496 | __rq = elv_rqhash_find(q, blk_rq_pos(rq)); |
| 497 | if (!__rq || !blk_attempt_req_merge(q, __rq, rq)) |
| 498 | break; |
Jens Axboe | 5e84ea3 | 2011-03-21 10:14:27 +0100 | [diff] [blame] | 499 | |
Shaohua Li | bee0393 | 2012-11-09 08:44:27 +0100 | [diff] [blame] | 500 | /* The merged request could be merged with others, try again */ |
| 501 | ret = true; |
| 502 | rq = __rq; |
| 503 | } |
| 504 | |
| 505 | return ret; |
Jens Axboe | 5e84ea3 | 2011-03-21 10:14:27 +0100 | [diff] [blame] | 506 | } |
| 507 | |
Christoph Hellwig | 34fe7c0 | 2017-02-08 14:46:48 +0100 | [diff] [blame] | 508 | void elv_merged_request(struct request_queue *q, struct request *rq, |
| 509 | enum elv_merge type) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 510 | { |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 511 | struct elevator_queue *e = q->elevator; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 512 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 513 | if (e->uses_mq && e->type->ops.mq.request_merged) |
| 514 | e->type->ops.mq.request_merged(q, rq, type); |
| 515 | else if (!e->uses_mq && e->type->ops.sq.elevator_merged_fn) |
Jens Axboe | c51ca6c | 2016-12-10 15:13:59 -0700 | [diff] [blame] | 516 | e->type->ops.sq.elevator_merged_fn(q, rq, type); |
Tejun Heo | 06b8624 | 2005-10-20 16:46:23 +0200 | [diff] [blame] | 517 | |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 518 | if (type == ELEVATOR_BACK_MERGE) |
| 519 | elv_rqhash_reposition(q, rq); |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 520 | |
Tejun Heo | 06b8624 | 2005-10-20 16:46:23 +0200 | [diff] [blame] | 521 | q->last_merge = rq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 522 | } |
| 523 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 524 | void elv_merge_requests(struct request_queue *q, struct request *rq, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 525 | struct request *next) |
| 526 | { |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 527 | struct elevator_queue *e = q->elevator; |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 528 | bool next_sorted = false; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 529 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 530 | if (e->uses_mq && e->type->ops.mq.requests_merged) |
| 531 | e->type->ops.mq.requests_merged(q, rq, next); |
| 532 | else if (e->type->ops.sq.elevator_merge_req_fn) { |
Bart Van Assche | a1ae0f7 | 2017-02-01 12:22:23 -0700 | [diff] [blame] | 533 | next_sorted = (__force bool)(next->rq_flags & RQF_SORTED); |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 534 | if (next_sorted) |
| 535 | e->type->ops.sq.elevator_merge_req_fn(q, rq, next); |
| 536 | } |
Tejun Heo | 06b8624 | 2005-10-20 16:46:23 +0200 | [diff] [blame] | 537 | |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 538 | elv_rqhash_reposition(q, rq); |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 539 | |
Jens Axboe | 5e84ea3 | 2011-03-21 10:14:27 +0100 | [diff] [blame] | 540 | if (next_sorted) { |
| 541 | elv_rqhash_del(q, next); |
| 542 | q->nr_sorted--; |
| 543 | } |
| 544 | |
Tejun Heo | 06b8624 | 2005-10-20 16:46:23 +0200 | [diff] [blame] | 545 | q->last_merge = rq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 546 | } |
| 547 | |
Divyesh Shah | 812d402 | 2010-04-08 21:14:23 -0700 | [diff] [blame] | 548 | void elv_bio_merged(struct request_queue *q, struct request *rq, |
| 549 | struct bio *bio) |
| 550 | { |
| 551 | struct elevator_queue *e = q->elevator; |
| 552 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 553 | if (WARN_ON_ONCE(e->uses_mq)) |
| 554 | return; |
| 555 | |
Jens Axboe | c51ca6c | 2016-12-10 15:13:59 -0700 | [diff] [blame] | 556 | if (e->type->ops.sq.elevator_bio_merged_fn) |
| 557 | e->type->ops.sq.elevator_bio_merged_fn(q, rq, bio); |
Divyesh Shah | 812d402 | 2010-04-08 21:14:23 -0700 | [diff] [blame] | 558 | } |
| 559 | |
Rafael J. Wysocki | 47fafbc | 2014-12-04 01:00:23 +0100 | [diff] [blame] | 560 | #ifdef CONFIG_PM |
Lin Ming | c815881 | 2013-03-23 11:42:27 +0800 | [diff] [blame] | 561 | static void blk_pm_requeue_request(struct request *rq) |
| 562 | { |
Christoph Hellwig | e806402 | 2016-10-20 15:12:13 +0200 | [diff] [blame] | 563 | if (rq->q->dev && !(rq->rq_flags & RQF_PM)) |
Lin Ming | c815881 | 2013-03-23 11:42:27 +0800 | [diff] [blame] | 564 | rq->q->nr_pending--; |
| 565 | } |
| 566 | |
| 567 | static void blk_pm_add_request(struct request_queue *q, struct request *rq) |
| 568 | { |
Christoph Hellwig | e806402 | 2016-10-20 15:12:13 +0200 | [diff] [blame] | 569 | if (q->dev && !(rq->rq_flags & RQF_PM) && q->nr_pending++ == 0 && |
Lin Ming | c815881 | 2013-03-23 11:42:27 +0800 | [diff] [blame] | 570 | (q->rpm_status == RPM_SUSPENDED || q->rpm_status == RPM_SUSPENDING)) |
| 571 | pm_request_resume(q->dev); |
| 572 | } |
| 573 | #else |
| 574 | static inline void blk_pm_requeue_request(struct request *rq) {} |
| 575 | static inline void blk_pm_add_request(struct request_queue *q, |
| 576 | struct request *rq) |
| 577 | { |
| 578 | } |
| 579 | #endif |
| 580 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 581 | void elv_requeue_request(struct request_queue *q, struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 582 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 583 | /* |
| 584 | * it already went through dequeue, we need to decrement the |
| 585 | * in_flight count again |
| 586 | */ |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 587 | if (blk_account_rq(rq)) { |
Jens Axboe | 0a7ae2f | 2009-05-20 08:54:31 +0200 | [diff] [blame] | 588 | q->in_flight[rq_is_sync(rq)]--; |
Christoph Hellwig | e806402 | 2016-10-20 15:12:13 +0200 | [diff] [blame] | 589 | if (rq->rq_flags & RQF_SORTED) |
Jens Axboe | cad9751 | 2007-01-14 22:26:09 +1100 | [diff] [blame] | 590 | elv_deactivate_rq(q, rq); |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 591 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 592 | |
Christoph Hellwig | e806402 | 2016-10-20 15:12:13 +0200 | [diff] [blame] | 593 | rq->rq_flags &= ~RQF_STARTED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 594 | |
Lin Ming | c815881 | 2013-03-23 11:42:27 +0800 | [diff] [blame] | 595 | blk_pm_requeue_request(rq); |
| 596 | |
Jens Axboe | b710a48 | 2011-03-30 09:52:30 +0200 | [diff] [blame] | 597 | __elv_add_request(q, rq, ELEVATOR_INSERT_REQUEUE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 598 | } |
| 599 | |
Jerome Marchand | 26308ea | 2009-03-27 10:31:51 +0100 | [diff] [blame] | 600 | void elv_drain_elevator(struct request_queue *q) |
Tejun Heo | 15853af | 2005-11-10 08:52:05 +0100 | [diff] [blame] | 601 | { |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 602 | struct elevator_queue *e = q->elevator; |
Tejun Heo | 15853af | 2005-11-10 08:52:05 +0100 | [diff] [blame] | 603 | static int printed; |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 604 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 605 | if (WARN_ON_ONCE(e->uses_mq)) |
| 606 | return; |
| 607 | |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 608 | lockdep_assert_held(q->queue_lock); |
| 609 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 610 | while (e->type->ops.sq.elevator_dispatch_fn(q, 1)) |
Tejun Heo | 15853af | 2005-11-10 08:52:05 +0100 | [diff] [blame] | 611 | ; |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 612 | if (q->nr_sorted && printed++ < 10) { |
Tejun Heo | 15853af | 2005-11-10 08:52:05 +0100 | [diff] [blame] | 613 | printk(KERN_ERR "%s: forced dispatching is broken " |
| 614 | "(nr_sorted=%u), please report this\n", |
Tejun Heo | 22f746e | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 615 | q->elevator->type->elevator_name, q->nr_sorted); |
Tejun Heo | 15853af | 2005-11-10 08:52:05 +0100 | [diff] [blame] | 616 | } |
| 617 | } |
| 618 | |
Jens Axboe | b710a48 | 2011-03-30 09:52:30 +0200 | [diff] [blame] | 619 | void __elv_add_request(struct request_queue *q, struct request *rq, int where) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 620 | { |
Arnaldo Carvalho de Melo | 5f3ea37 | 2008-10-30 08:34:33 +0100 | [diff] [blame] | 621 | trace_block_rq_insert(q, rq); |
Jens Axboe | 2056a78 | 2006-03-23 20:00:26 +0100 | [diff] [blame] | 622 | |
Lin Ming | c815881 | 2013-03-23 11:42:27 +0800 | [diff] [blame] | 623 | blk_pm_add_request(q, rq); |
| 624 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 625 | rq->q = q; |
| 626 | |
Christoph Hellwig | e806402 | 2016-10-20 15:12:13 +0200 | [diff] [blame] | 627 | if (rq->rq_flags & RQF_SOFTBARRIER) { |
Jens Axboe | b710a48 | 2011-03-30 09:52:30 +0200 | [diff] [blame] | 628 | /* barriers are scheduling boundary, update end_sector */ |
Christoph Hellwig | 57292b5 | 2017-01-31 16:57:29 +0100 | [diff] [blame] | 629 | if (!blk_rq_is_passthrough(rq)) { |
Jens Axboe | b710a48 | 2011-03-30 09:52:30 +0200 | [diff] [blame] | 630 | q->end_sector = rq_end_sector(rq); |
| 631 | q->boundary_rq = rq; |
| 632 | } |
Christoph Hellwig | e806402 | 2016-10-20 15:12:13 +0200 | [diff] [blame] | 633 | } else if (!(rq->rq_flags & RQF_ELVPRIV) && |
Jens Axboe | 3aa7287 | 2011-04-21 19:28:35 +0200 | [diff] [blame] | 634 | (where == ELEVATOR_INSERT_SORT || |
| 635 | where == ELEVATOR_INSERT_SORT_MERGE)) |
Jens Axboe | b710a48 | 2011-03-30 09:52:30 +0200 | [diff] [blame] | 636 | where = ELEVATOR_INSERT_BACK; |
| 637 | |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 638 | switch (where) { |
Tejun Heo | 28e7d18 | 2010-09-03 11:56:16 +0200 | [diff] [blame] | 639 | case ELEVATOR_INSERT_REQUEUE: |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 640 | case ELEVATOR_INSERT_FRONT: |
Christoph Hellwig | e806402 | 2016-10-20 15:12:13 +0200 | [diff] [blame] | 641 | rq->rq_flags |= RQF_SOFTBARRIER; |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 642 | list_add(&rq->queuelist, &q->queue_head); |
| 643 | break; |
| 644 | |
| 645 | case ELEVATOR_INSERT_BACK: |
Christoph Hellwig | e806402 | 2016-10-20 15:12:13 +0200 | [diff] [blame] | 646 | rq->rq_flags |= RQF_SOFTBARRIER; |
Tejun Heo | 15853af | 2005-11-10 08:52:05 +0100 | [diff] [blame] | 647 | elv_drain_elevator(q); |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 648 | list_add_tail(&rq->queuelist, &q->queue_head); |
| 649 | /* |
| 650 | * We kick the queue here for the following reasons. |
| 651 | * - The elevator might have returned NULL previously |
| 652 | * to delay requests and returned them now. As the |
| 653 | * queue wasn't empty before this request, ll_rw_blk |
| 654 | * won't run the queue on return, resulting in hang. |
| 655 | * - Usually, back inserted requests won't be merged |
| 656 | * with anything. There's no point in delaying queue |
| 657 | * processing. |
| 658 | */ |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 659 | __blk_run_queue(q); |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 660 | break; |
| 661 | |
Jens Axboe | 5e84ea3 | 2011-03-21 10:14:27 +0100 | [diff] [blame] | 662 | case ELEVATOR_INSERT_SORT_MERGE: |
| 663 | /* |
| 664 | * If we succeed in merging this request with one in the |
| 665 | * queue already, we are done - rq has now been freed, |
| 666 | * so no need to do anything further. |
| 667 | */ |
| 668 | if (elv_attempt_insert_merge(q, rq)) |
| 669 | break; |
Bart Van Assche | e29387e | 2017-06-21 09:40:11 -0700 | [diff] [blame] | 670 | /* fall through */ |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 671 | case ELEVATOR_INSERT_SORT: |
Christoph Hellwig | 57292b5 | 2017-01-31 16:57:29 +0100 | [diff] [blame] | 672 | BUG_ON(blk_rq_is_passthrough(rq)); |
Christoph Hellwig | e806402 | 2016-10-20 15:12:13 +0200 | [diff] [blame] | 673 | rq->rq_flags |= RQF_SORTED; |
Tejun Heo | 15853af | 2005-11-10 08:52:05 +0100 | [diff] [blame] | 674 | q->nr_sorted++; |
Jens Axboe | 9817064 | 2006-07-28 09:23:08 +0200 | [diff] [blame] | 675 | if (rq_mergeable(rq)) { |
| 676 | elv_rqhash_add(q, rq); |
| 677 | if (!q->last_merge) |
| 678 | q->last_merge = rq; |
| 679 | } |
| 680 | |
Tejun Heo | ca23509 | 2005-11-01 17:23:49 +0900 | [diff] [blame] | 681 | /* |
| 682 | * Some ioscheds (cfq) run q->request_fn directly, so |
| 683 | * rq cannot be accessed after calling |
| 684 | * elevator_add_req_fn. |
| 685 | */ |
Jens Axboe | c51ca6c | 2016-12-10 15:13:59 -0700 | [diff] [blame] | 686 | q->elevator->type->ops.sq.elevator_add_req_fn(q, rq); |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 687 | break; |
| 688 | |
Tejun Heo | ae1b153 | 2011-01-25 12:43:54 +0100 | [diff] [blame] | 689 | case ELEVATOR_INSERT_FLUSH: |
Christoph Hellwig | e806402 | 2016-10-20 15:12:13 +0200 | [diff] [blame] | 690 | rq->rq_flags |= RQF_SOFTBARRIER; |
Tejun Heo | ae1b153 | 2011-01-25 12:43:54 +0100 | [diff] [blame] | 691 | blk_insert_flush(rq); |
| 692 | break; |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 693 | default: |
| 694 | printk(KERN_ERR "%s: bad insertion point %d\n", |
Harvey Harrison | 24c03d4 | 2008-05-01 04:35:17 -0700 | [diff] [blame] | 695 | __func__, where); |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 696 | BUG(); |
| 697 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 698 | } |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 699 | EXPORT_SYMBOL(__elv_add_request); |
| 700 | |
Jens Axboe | 7eaceac | 2011-03-10 08:52:07 +0100 | [diff] [blame] | 701 | void elv_add_request(struct request_queue *q, struct request *rq, int where) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 702 | { |
| 703 | unsigned long flags; |
| 704 | |
| 705 | spin_lock_irqsave(q->queue_lock, flags); |
Jens Axboe | 7eaceac | 2011-03-10 08:52:07 +0100 | [diff] [blame] | 706 | __elv_add_request(q, rq, where); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 707 | spin_unlock_irqrestore(q->queue_lock, flags); |
| 708 | } |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 709 | EXPORT_SYMBOL(elv_add_request); |
| 710 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 711 | struct request *elv_latter_request(struct request_queue *q, struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 712 | { |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 713 | struct elevator_queue *e = q->elevator; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 714 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 715 | if (e->uses_mq && e->type->ops.mq.next_request) |
| 716 | return e->type->ops.mq.next_request(q, rq); |
| 717 | else if (!e->uses_mq && e->type->ops.sq.elevator_latter_req_fn) |
Jens Axboe | c51ca6c | 2016-12-10 15:13:59 -0700 | [diff] [blame] | 718 | return e->type->ops.sq.elevator_latter_req_fn(q, rq); |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 719 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 720 | return NULL; |
| 721 | } |
| 722 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 723 | struct request *elv_former_request(struct request_queue *q, struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 724 | { |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 725 | struct elevator_queue *e = q->elevator; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 726 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 727 | if (e->uses_mq && e->type->ops.mq.former_request) |
| 728 | return e->type->ops.mq.former_request(q, rq); |
| 729 | if (!e->uses_mq && e->type->ops.sq.elevator_former_req_fn) |
Jens Axboe | c51ca6c | 2016-12-10 15:13:59 -0700 | [diff] [blame] | 730 | return e->type->ops.sq.elevator_former_req_fn(q, rq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 731 | return NULL; |
| 732 | } |
| 733 | |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 734 | int elv_set_request(struct request_queue *q, struct request *rq, |
| 735 | struct bio *bio, gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 736 | { |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 737 | struct elevator_queue *e = q->elevator; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 738 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 739 | if (WARN_ON_ONCE(e->uses_mq)) |
| 740 | return 0; |
| 741 | |
Jens Axboe | c51ca6c | 2016-12-10 15:13:59 -0700 | [diff] [blame] | 742 | if (e->type->ops.sq.elevator_set_req_fn) |
| 743 | return e->type->ops.sq.elevator_set_req_fn(q, rq, bio, gfp_mask); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 744 | return 0; |
| 745 | } |
| 746 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 747 | void elv_put_request(struct request_queue *q, struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 748 | { |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 749 | struct elevator_queue *e = q->elevator; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 750 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 751 | if (WARN_ON_ONCE(e->uses_mq)) |
| 752 | return; |
| 753 | |
Jens Axboe | c51ca6c | 2016-12-10 15:13:59 -0700 | [diff] [blame] | 754 | if (e->type->ops.sq.elevator_put_req_fn) |
| 755 | e->type->ops.sq.elevator_put_req_fn(rq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 756 | } |
| 757 | |
Christoph Hellwig | ef295ec | 2016-10-28 08:48:16 -0600 | [diff] [blame] | 758 | int elv_may_queue(struct request_queue *q, unsigned int op) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 759 | { |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 760 | struct elevator_queue *e = q->elevator; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 761 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 762 | if (WARN_ON_ONCE(e->uses_mq)) |
| 763 | return 0; |
| 764 | |
Jens Axboe | c51ca6c | 2016-12-10 15:13:59 -0700 | [diff] [blame] | 765 | if (e->type->ops.sq.elevator_may_queue_fn) |
| 766 | return e->type->ops.sq.elevator_may_queue_fn(q, op); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 767 | |
| 768 | return ELV_MQUEUE_MAY; |
| 769 | } |
| 770 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 771 | void elv_completed_request(struct request_queue *q, struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 772 | { |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 773 | struct elevator_queue *e = q->elevator; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 774 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 775 | if (WARN_ON_ONCE(e->uses_mq)) |
| 776 | return; |
| 777 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 778 | /* |
| 779 | * request is released from the driver, io must be done |
| 780 | */ |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 781 | if (blk_account_rq(rq)) { |
Jens Axboe | 0a7ae2f | 2009-05-20 08:54:31 +0200 | [diff] [blame] | 782 | q->in_flight[rq_is_sync(rq)]--; |
Christoph Hellwig | e806402 | 2016-10-20 15:12:13 +0200 | [diff] [blame] | 783 | if ((rq->rq_flags & RQF_SORTED) && |
Jens Axboe | c51ca6c | 2016-12-10 15:13:59 -0700 | [diff] [blame] | 784 | e->type->ops.sq.elevator_completed_req_fn) |
| 785 | e->type->ops.sq.elevator_completed_req_fn(q, rq); |
Tejun Heo | 1bc691d | 2006-01-12 15:39:26 +0100 | [diff] [blame] | 786 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 787 | } |
| 788 | |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 789 | #define to_elv(atr) container_of((atr), struct elv_fs_entry, attr) |
| 790 | |
| 791 | static ssize_t |
| 792 | elv_attr_show(struct kobject *kobj, struct attribute *attr, char *page) |
| 793 | { |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 794 | struct elv_fs_entry *entry = to_elv(attr); |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 795 | struct elevator_queue *e; |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 796 | ssize_t error; |
| 797 | |
| 798 | if (!entry->show) |
| 799 | return -EIO; |
| 800 | |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 801 | e = container_of(kobj, struct elevator_queue, kobj); |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 802 | mutex_lock(&e->sysfs_lock); |
Tejun Heo | 22f746e | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 803 | error = e->type ? entry->show(e, page) : -ENOENT; |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 804 | mutex_unlock(&e->sysfs_lock); |
| 805 | return error; |
| 806 | } |
| 807 | |
| 808 | static ssize_t |
| 809 | elv_attr_store(struct kobject *kobj, struct attribute *attr, |
| 810 | const char *page, size_t length) |
| 811 | { |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 812 | struct elv_fs_entry *entry = to_elv(attr); |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 813 | struct elevator_queue *e; |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 814 | ssize_t error; |
| 815 | |
| 816 | if (!entry->store) |
| 817 | return -EIO; |
| 818 | |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 819 | e = container_of(kobj, struct elevator_queue, kobj); |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 820 | mutex_lock(&e->sysfs_lock); |
Tejun Heo | 22f746e | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 821 | error = e->type ? entry->store(e, page, length) : -ENOENT; |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 822 | mutex_unlock(&e->sysfs_lock); |
| 823 | return error; |
| 824 | } |
| 825 | |
Emese Revfy | 52cf25d | 2010-01-19 02:58:23 +0100 | [diff] [blame] | 826 | static const struct sysfs_ops elv_sysfs_ops = { |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 827 | .show = elv_attr_show, |
| 828 | .store = elv_attr_store, |
| 829 | }; |
| 830 | |
| 831 | static struct kobj_type elv_ktype = { |
| 832 | .sysfs_ops = &elv_sysfs_ops, |
| 833 | .release = elevator_release, |
| 834 | }; |
| 835 | |
Tejun Heo | 5a5bafd | 2012-03-05 13:14:56 -0800 | [diff] [blame] | 836 | int elv_register_queue(struct request_queue *q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 837 | { |
Tejun Heo | 5a5bafd | 2012-03-05 13:14:56 -0800 | [diff] [blame] | 838 | struct elevator_queue *e = q->elevator; |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 839 | int error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 840 | |
Bart Van Assche | 14a2349 | 2018-01-17 11:48:09 -0800 | [diff] [blame] | 841 | lockdep_assert_held(&q->sysfs_lock); |
| 842 | |
Greg Kroah-Hartman | b2d6db5 | 2007-12-17 23:05:35 -0700 | [diff] [blame] | 843 | error = kobject_add(&e->kobj, &q->kobj, "%s", "iosched"); |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 844 | if (!error) { |
Tejun Heo | 22f746e | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 845 | struct elv_fs_entry *attr = e->type->elevator_attrs; |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 846 | if (attr) { |
Al Viro | e572ec7 | 2006-03-18 22:27:18 -0500 | [diff] [blame] | 847 | while (attr->attr.name) { |
| 848 | if (sysfs_create_file(&e->kobj, &attr->attr)) |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 849 | break; |
Al Viro | e572ec7 | 2006-03-18 22:27:18 -0500 | [diff] [blame] | 850 | attr++; |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 851 | } |
| 852 | } |
| 853 | kobject_uevent(&e->kobj, KOBJ_ADD); |
Jens Axboe | 430c62f | 2010-10-07 09:35:16 +0200 | [diff] [blame] | 854 | e->registered = 1; |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 855 | if (!e->uses_mq && e->type->ops.sq.elevator_registered_fn) |
Jens Axboe | c51ca6c | 2016-12-10 15:13:59 -0700 | [diff] [blame] | 856 | e->type->ops.sq.elevator_registered_fn(q); |
Al Viro | 3d1ab40 | 2006-03-18 18:35:43 -0500 | [diff] [blame] | 857 | } |
| 858 | return error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 859 | } |
Jens Axboe | bc1c116 | 2006-06-08 08:49:06 +0200 | [diff] [blame] | 860 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 861 | void elv_unregister_queue(struct request_queue *q) |
| 862 | { |
Bart Van Assche | 14a2349 | 2018-01-17 11:48:09 -0800 | [diff] [blame] | 863 | lockdep_assert_held(&q->sysfs_lock); |
| 864 | |
Tejun Heo | f8fc877 | 2011-12-14 00:33:40 +0100 | [diff] [blame] | 865 | if (q) { |
| 866 | struct elevator_queue *e = q->elevator; |
| 867 | |
| 868 | kobject_uevent(&e->kobj, KOBJ_REMOVE); |
| 869 | kobject_del(&e->kobj); |
| 870 | e->registered = 0; |
Jan Kara | 8330cdb | 2017-04-19 11:33:27 +0200 | [diff] [blame] | 871 | /* Re-enable throttling in case elevator disabled it */ |
| 872 | wbt_enable_default(q); |
Tejun Heo | f8fc877 | 2011-12-14 00:33:40 +0100 | [diff] [blame] | 873 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 874 | } |
| 875 | |
Jens Axboe | e567bf7 | 2014-06-22 16:32:48 -0600 | [diff] [blame] | 876 | int elv_register(struct elevator_type *e) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 877 | { |
Thibaut VARENE | 1ffb96c | 2007-03-15 12:59:19 +0100 | [diff] [blame] | 878 | char *def = ""; |
Jens Axboe | 2a12dcd | 2007-04-26 14:41:53 +0200 | [diff] [blame] | 879 | |
Tejun Heo | 3d3c237 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 880 | /* create icq_cache if requested */ |
| 881 | if (e->icq_size) { |
| 882 | if (WARN_ON(e->icq_size < sizeof(struct io_cq)) || |
| 883 | WARN_ON(e->icq_align < __alignof__(struct io_cq))) |
| 884 | return -EINVAL; |
| 885 | |
| 886 | snprintf(e->icq_cache_name, sizeof(e->icq_cache_name), |
| 887 | "%s_io_cq", e->elevator_name); |
| 888 | e->icq_cache = kmem_cache_create(e->icq_cache_name, e->icq_size, |
| 889 | e->icq_align, 0, NULL); |
| 890 | if (!e->icq_cache) |
| 891 | return -ENOMEM; |
| 892 | } |
| 893 | |
| 894 | /* register, don't allow duplicate names */ |
Jens Axboe | 2a12dcd | 2007-04-26 14:41:53 +0200 | [diff] [blame] | 895 | spin_lock(&elv_list_lock); |
Jens Axboe | 2527d99 | 2017-10-25 12:33:42 -0600 | [diff] [blame] | 896 | if (elevator_find(e->elevator_name, e->uses_mq)) { |
Tejun Heo | 3d3c237 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 897 | spin_unlock(&elv_list_lock); |
| 898 | if (e->icq_cache) |
| 899 | kmem_cache_destroy(e->icq_cache); |
| 900 | return -EBUSY; |
| 901 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 902 | list_add_tail(&e->list, &elv_list); |
Jens Axboe | 2a12dcd | 2007-04-26 14:41:53 +0200 | [diff] [blame] | 903 | spin_unlock(&elv_list_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 904 | |
Tejun Heo | 3d3c237 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 905 | /* print pretty message */ |
Jens Axboe | 8ac0d9a | 2017-10-25 12:35:02 -0600 | [diff] [blame] | 906 | if (elevator_match(e, chosen_elevator) || |
Nate Diller | 5f00397 | 2006-01-24 10:07:58 +0100 | [diff] [blame] | 907 | (!*chosen_elevator && |
Jens Axboe | 8ac0d9a | 2017-10-25 12:35:02 -0600 | [diff] [blame] | 908 | elevator_match(e, CONFIG_DEFAULT_IOSCHED))) |
Thibaut VARENE | 1ffb96c | 2007-03-15 12:59:19 +0100 | [diff] [blame] | 909 | def = " (default)"; |
| 910 | |
Jens Axboe | 4eb166d | 2008-02-01 00:37:27 +0100 | [diff] [blame] | 911 | printk(KERN_INFO "io scheduler %s registered%s\n", e->elevator_name, |
| 912 | def); |
Tejun Heo | 3d3c237 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 913 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 914 | } |
| 915 | EXPORT_SYMBOL_GPL(elv_register); |
| 916 | |
| 917 | void elv_unregister(struct elevator_type *e) |
| 918 | { |
Tejun Heo | 3d3c237 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 919 | /* unregister */ |
Jens Axboe | 2a12dcd | 2007-04-26 14:41:53 +0200 | [diff] [blame] | 920 | spin_lock(&elv_list_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 921 | list_del_init(&e->list); |
Jens Axboe | 2a12dcd | 2007-04-26 14:41:53 +0200 | [diff] [blame] | 922 | spin_unlock(&elv_list_lock); |
Tejun Heo | 3d3c237 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 923 | |
| 924 | /* |
| 925 | * Destroy icq_cache if it exists. icq's are RCU managed. Make |
| 926 | * sure all RCU operations are complete before proceeding. |
| 927 | */ |
| 928 | if (e->icq_cache) { |
| 929 | rcu_barrier(); |
| 930 | kmem_cache_destroy(e->icq_cache); |
| 931 | e->icq_cache = NULL; |
| 932 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 933 | } |
| 934 | EXPORT_SYMBOL_GPL(elv_unregister); |
| 935 | |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 936 | static int elevator_switch_mq(struct request_queue *q, |
| 937 | struct elevator_type *new_e) |
| 938 | { |
| 939 | int ret; |
| 940 | |
Bart Van Assche | 14a2349 | 2018-01-17 11:48:09 -0800 | [diff] [blame] | 941 | lockdep_assert_held(&q->sysfs_lock); |
| 942 | |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 943 | blk_mq_freeze_queue(q); |
Ming Lei | 24f5a90 | 2018-01-06 16:27:38 +0800 | [diff] [blame] | 944 | blk_mq_quiesce_queue(q); |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 945 | |
| 946 | if (q->elevator) { |
| 947 | if (q->elevator->registered) |
| 948 | elv_unregister_queue(q); |
| 949 | ioc_clear_queue(q); |
| 950 | elevator_exit(q, q->elevator); |
| 951 | } |
| 952 | |
| 953 | ret = blk_mq_init_sched(q, new_e); |
| 954 | if (ret) |
| 955 | goto out; |
| 956 | |
| 957 | if (new_e) { |
| 958 | ret = elv_register_queue(q); |
| 959 | if (ret) { |
| 960 | elevator_exit(q, q->elevator); |
| 961 | goto out; |
| 962 | } |
| 963 | } |
| 964 | |
| 965 | if (new_e) |
| 966 | blk_add_trace_msg(q, "elv switch: %s", new_e->elevator_name); |
| 967 | else |
| 968 | blk_add_trace_msg(q, "elv switch: none"); |
| 969 | |
| 970 | out: |
Ming Lei | 24f5a90 | 2018-01-06 16:27:38 +0800 | [diff] [blame] | 971 | blk_mq_unquiesce_queue(q); |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 972 | blk_mq_unfreeze_queue(q); |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 973 | return ret; |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 974 | } |
| 975 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 976 | /* |
Christoph Hellwig | 131d08e | 2018-05-31 19:11:40 +0200 | [diff] [blame^] | 977 | * For blk-mq devices, we default to using mq-deadline, if available, for single |
| 978 | * queue devices. If deadline isn't available OR we have multiple queues, |
| 979 | * default to "none". |
| 980 | */ |
| 981 | int elevator_init_mq(struct request_queue *q) |
| 982 | { |
| 983 | struct elevator_type *e; |
| 984 | int err = 0; |
| 985 | |
| 986 | if (q->nr_hw_queues != 1) |
| 987 | return 0; |
| 988 | |
| 989 | /* |
| 990 | * q->sysfs_lock must be held to provide mutual exclusion between |
| 991 | * elevator_switch() and here. |
| 992 | */ |
| 993 | mutex_lock(&q->sysfs_lock); |
| 994 | if (unlikely(q->elevator)) |
| 995 | goto out_unlock; |
| 996 | |
| 997 | e = elevator_get(q, "mq-deadline", false); |
| 998 | if (!e) |
| 999 | goto out_unlock; |
| 1000 | |
| 1001 | err = blk_mq_init_sched(q, e); |
| 1002 | if (err) |
| 1003 | elevator_put(e); |
| 1004 | out_unlock: |
| 1005 | mutex_unlock(&q->sysfs_lock); |
| 1006 | return err; |
| 1007 | } |
| 1008 | |
| 1009 | |
| 1010 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1011 | * switch to new_e io scheduler. be careful not to introduce deadlocks - |
| 1012 | * we don't free the old io scheduler, before we have allocated what we |
| 1013 | * need for the new one. this way we have a chance of going back to the old |
Tejun Heo | cb98fc8 | 2005-10-28 08:29:39 +0200 | [diff] [blame] | 1014 | * one, if the new one fails init for some reason. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1015 | */ |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1016 | static int elevator_switch(struct request_queue *q, struct elevator_type *new_e) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1017 | { |
Tejun Heo | 5a5bafd | 2012-03-05 13:14:56 -0800 | [diff] [blame] | 1018 | struct elevator_queue *old = q->elevator; |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1019 | bool old_registered = false; |
Tejun Heo | e8989fa | 2012-03-05 13:15:20 -0800 | [diff] [blame] | 1020 | int err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1021 | |
Bart Van Assche | 14a2349 | 2018-01-17 11:48:09 -0800 | [diff] [blame] | 1022 | lockdep_assert_held(&q->sysfs_lock); |
| 1023 | |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 1024 | if (q->mq_ops) |
| 1025 | return elevator_switch_mq(q, new_e); |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1026 | |
Tejun Heo | 5a5bafd | 2012-03-05 13:14:56 -0800 | [diff] [blame] | 1027 | /* |
| 1028 | * Turn on BYPASS and drain all requests w/ elevator private data. |
| 1029 | * Block layer doesn't call into a quiesced elevator - all requests |
| 1030 | * are directly put on the dispatch list without elevator data |
| 1031 | * using INSERT_BACK. All requests have SOFTBARRIER set and no |
| 1032 | * merge happens either. |
| 1033 | */ |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1034 | if (old) { |
| 1035 | old_registered = old->registered; |
Tejun Heo | cb98fc8 | 2005-10-28 08:29:39 +0200 | [diff] [blame] | 1036 | |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 1037 | blk_queue_bypass_start(q); |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1038 | |
| 1039 | /* unregister and clear all auxiliary data of the old elevator */ |
| 1040 | if (old_registered) |
| 1041 | elv_unregister_queue(q); |
| 1042 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1043 | ioc_clear_queue(q); |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1044 | } |
Tejun Heo | 5a5bafd | 2012-03-05 13:14:56 -0800 | [diff] [blame] | 1045 | |
| 1046 | /* allocate, init and register new elevator */ |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 1047 | err = new_e->ops.sq.elevator_init_fn(q, new_e); |
Omar Sandoval | 6917ff0 | 2017-04-05 12:01:30 -0700 | [diff] [blame] | 1048 | if (err) |
| 1049 | goto fail_init; |
Tejun Heo | 5a5bafd | 2012-03-05 13:14:56 -0800 | [diff] [blame] | 1050 | |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 1051 | err = elv_register_queue(q); |
| 1052 | if (err) |
| 1053 | goto fail_register; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1054 | |
Tejun Heo | 5a5bafd | 2012-03-05 13:14:56 -0800 | [diff] [blame] | 1055 | /* done, kill the old one and finish */ |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1056 | if (old) { |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 1057 | elevator_exit(q, old); |
| 1058 | blk_queue_bypass_end(q); |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1059 | } |
Nick Piggin | 75ad23b | 2008-04-29 14:48:33 +0200 | [diff] [blame] | 1060 | |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 1061 | blk_add_trace_msg(q, "elv switch: %s", new_e->elevator_name); |
Alan D. Brunelle | 4722dc5 | 2008-05-27 14:55:00 +0200 | [diff] [blame] | 1062 | |
Jens Axboe | 5dd531a | 2010-08-23 13:52:19 +0200 | [diff] [blame] | 1063 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1064 | |
| 1065 | fail_register: |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 1066 | elevator_exit(q, q->elevator); |
Tejun Heo | 5a5bafd | 2012-03-05 13:14:56 -0800 | [diff] [blame] | 1067 | fail_init: |
| 1068 | /* switch failed, restore and re-register old elevator */ |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1069 | if (old) { |
| 1070 | q->elevator = old; |
| 1071 | elv_register_queue(q); |
Omar Sandoval | 54d5329 | 2017-04-07 08:52:27 -0600 | [diff] [blame] | 1072 | blk_queue_bypass_end(q); |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1073 | } |
Nick Piggin | 75ad23b | 2008-04-29 14:48:33 +0200 | [diff] [blame] | 1074 | |
Jens Axboe | 5dd531a | 2010-08-23 13:52:19 +0200 | [diff] [blame] | 1075 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1076 | } |
| 1077 | |
Jens Axboe | 5dd531a | 2010-08-23 13:52:19 +0200 | [diff] [blame] | 1078 | /* |
| 1079 | * Switch this queue to the given IO scheduler. |
| 1080 | */ |
Tomoki Sekiyama | 7c8a367 | 2013-10-15 16:42:19 -0600 | [diff] [blame] | 1081 | static int __elevator_change(struct request_queue *q, const char *name) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1082 | { |
| 1083 | char elevator_name[ELV_NAME_MAX]; |
| 1084 | struct elevator_type *e; |
| 1085 | |
David Jeffery | e9a823f | 2017-08-28 10:52:44 -0600 | [diff] [blame] | 1086 | /* Make sure queue is not in the middle of being removed */ |
| 1087 | if (!test_bit(QUEUE_FLAG_REGISTERED, &q->queue_flags)) |
| 1088 | return -ENOENT; |
| 1089 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1090 | /* |
| 1091 | * Special case for mq, turn off scheduling |
| 1092 | */ |
| 1093 | if (q->mq_ops && !strncmp(name, "none", 4)) |
| 1094 | return elevator_switch(q, NULL); |
Martin K. Petersen | cd43e26 | 2009-05-22 17:17:52 -0400 | [diff] [blame] | 1095 | |
Li Zefan | ee2e992 | 2008-10-14 08:49:56 +0200 | [diff] [blame] | 1096 | strlcpy(elevator_name, name, sizeof(elevator_name)); |
Jens Axboe | 2527d99 | 2017-10-25 12:33:42 -0600 | [diff] [blame] | 1097 | e = elevator_get(q, strstrip(elevator_name), true); |
Jens Axboe | 340ff32 | 2017-05-10 07:40:04 -0600 | [diff] [blame] | 1098 | if (!e) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1099 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1100 | |
Jens Axboe | 8ac0d9a | 2017-10-25 12:35:02 -0600 | [diff] [blame] | 1101 | if (q->elevator && elevator_match(q->elevator->type, elevator_name)) { |
Nate Diller | 2ca7d93 | 2005-10-30 15:02:24 -0800 | [diff] [blame] | 1102 | elevator_put(e); |
Jens Axboe | 5dd531a | 2010-08-23 13:52:19 +0200 | [diff] [blame] | 1103 | return 0; |
Nate Diller | 2ca7d93 | 2005-10-30 15:02:24 -0800 | [diff] [blame] | 1104 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1105 | |
Jens Axboe | 5dd531a | 2010-08-23 13:52:19 +0200 | [diff] [blame] | 1106 | return elevator_switch(q, e); |
| 1107 | } |
Tomoki Sekiyama | 7c8a367 | 2013-10-15 16:42:19 -0600 | [diff] [blame] | 1108 | |
Ming Lei | 3a5088c | 2017-04-15 20:38:22 +0800 | [diff] [blame] | 1109 | static inline bool elv_support_iosched(struct request_queue *q) |
| 1110 | { |
| 1111 | if (q->mq_ops && q->tag_set && (q->tag_set->flags & |
| 1112 | BLK_MQ_F_NO_SCHED)) |
| 1113 | return false; |
| 1114 | return true; |
| 1115 | } |
| 1116 | |
Jens Axboe | 5dd531a | 2010-08-23 13:52:19 +0200 | [diff] [blame] | 1117 | ssize_t elv_iosched_store(struct request_queue *q, const char *name, |
| 1118 | size_t count) |
| 1119 | { |
| 1120 | int ret; |
| 1121 | |
Ming Lei | 3a5088c | 2017-04-15 20:38:22 +0800 | [diff] [blame] | 1122 | if (!(q->mq_ops || q->request_fn) || !elv_support_iosched(q)) |
Jens Axboe | 5dd531a | 2010-08-23 13:52:19 +0200 | [diff] [blame] | 1123 | return count; |
| 1124 | |
Tomoki Sekiyama | 7c8a367 | 2013-10-15 16:42:19 -0600 | [diff] [blame] | 1125 | ret = __elevator_change(q, name); |
Jens Axboe | 5dd531a | 2010-08-23 13:52:19 +0200 | [diff] [blame] | 1126 | if (!ret) |
| 1127 | return count; |
| 1128 | |
Jens Axboe | 5dd531a | 2010-08-23 13:52:19 +0200 | [diff] [blame] | 1129 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1130 | } |
| 1131 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1132 | ssize_t elv_iosched_show(struct request_queue *q, char *name) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1133 | { |
Jens Axboe | b374d18 | 2008-10-31 10:05:07 +0100 | [diff] [blame] | 1134 | struct elevator_queue *e = q->elevator; |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1135 | struct elevator_type *elv = NULL; |
Matthias Kaehlcke | 70cee26 | 2007-07-10 12:26:24 +0200 | [diff] [blame] | 1136 | struct elevator_type *__e; |
Jens Axboe | 8ac0d9a | 2017-10-25 12:35:02 -0600 | [diff] [blame] | 1137 | bool uses_mq = q->mq_ops != NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1138 | int len = 0; |
| 1139 | |
Christoph Hellwig | 5fdee21 | 2017-10-05 21:22:52 +0200 | [diff] [blame] | 1140 | if (!queue_is_rq_based(q)) |
Martin K. Petersen | cd43e26 | 2009-05-22 17:17:52 -0400 | [diff] [blame] | 1141 | return sprintf(name, "none\n"); |
| 1142 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1143 | if (!q->elevator) |
| 1144 | len += sprintf(name+len, "[none] "); |
| 1145 | else |
| 1146 | elv = e->type; |
Martin K. Petersen | cd43e26 | 2009-05-22 17:17:52 -0400 | [diff] [blame] | 1147 | |
Jens Axboe | 2a12dcd | 2007-04-26 14:41:53 +0200 | [diff] [blame] | 1148 | spin_lock(&elv_list_lock); |
Matthias Kaehlcke | 70cee26 | 2007-07-10 12:26:24 +0200 | [diff] [blame] | 1149 | list_for_each_entry(__e, &elv_list, list) { |
Jens Axboe | 8ac0d9a | 2017-10-25 12:35:02 -0600 | [diff] [blame] | 1150 | if (elv && elevator_match(elv, __e->elevator_name) && |
| 1151 | (__e->uses_mq == uses_mq)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1152 | len += sprintf(name+len, "[%s] ", elv->elevator_name); |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1153 | continue; |
| 1154 | } |
Ming Lei | 3a5088c | 2017-04-15 20:38:22 +0800 | [diff] [blame] | 1155 | if (__e->uses_mq && q->mq_ops && elv_support_iosched(q)) |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1156 | len += sprintf(name+len, "%s ", __e->elevator_name); |
| 1157 | else if (!__e->uses_mq && !q->mq_ops) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1158 | len += sprintf(name+len, "%s ", __e->elevator_name); |
| 1159 | } |
Jens Axboe | 2a12dcd | 2007-04-26 14:41:53 +0200 | [diff] [blame] | 1160 | spin_unlock(&elv_list_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1161 | |
Jens Axboe | bd166ef | 2017-01-17 06:03:22 -0700 | [diff] [blame] | 1162 | if (q->mq_ops && q->elevator) |
| 1163 | len += sprintf(name+len, "none"); |
| 1164 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1165 | len += sprintf(len+name, "\n"); |
| 1166 | return len; |
| 1167 | } |
| 1168 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1169 | struct request *elv_rb_former_request(struct request_queue *q, |
| 1170 | struct request *rq) |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 1171 | { |
| 1172 | struct rb_node *rbprev = rb_prev(&rq->rb_node); |
| 1173 | |
| 1174 | if (rbprev) |
| 1175 | return rb_entry_rq(rbprev); |
| 1176 | |
| 1177 | return NULL; |
| 1178 | } |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 1179 | EXPORT_SYMBOL(elv_rb_former_request); |
| 1180 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1181 | struct request *elv_rb_latter_request(struct request_queue *q, |
| 1182 | struct request *rq) |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 1183 | { |
| 1184 | struct rb_node *rbnext = rb_next(&rq->rb_node); |
| 1185 | |
| 1186 | if (rbnext) |
| 1187 | return rb_entry_rq(rbnext); |
| 1188 | |
| 1189 | return NULL; |
| 1190 | } |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 1191 | EXPORT_SYMBOL(elv_rb_latter_request); |