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Vivek Goyal31e4c282009-12-03 12:59:42 -05001#ifndef _BLK_CGROUP_H
2#define _BLK_CGROUP_H
3/*
4 * Common Block IO controller cgroup interface
5 *
6 * Based on ideas and code from CFQ, CFS and BFQ:
7 * Copyright (C) 2003 Jens Axboe <axboe@kernel.dk>
8 *
9 * Copyright (C) 2008 Fabio Checconi <fabio@gandalf.sssup.it>
10 * Paolo Valente <paolo.valente@unimore.it>
11 *
12 * Copyright (C) 2009 Vivek Goyal <vgoyal@redhat.com>
13 * Nauman Rafique <nauman@google.com>
14 */
15
16#include <linux/cgroup.h>
17
Ben Blum67523c42010-03-10 15:22:11 -080018#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
19
20#ifndef CONFIG_BLK_CGROUP
21/* When blk-cgroup is a module, its subsys_id isn't a compile-time constant */
22extern struct cgroup_subsys blkio_subsys;
23#define blkio_subsys_id blkio_subsys.subsys_id
24#endif
Jens Axboe2f5ea472009-12-03 21:06:43 +010025
Divyesh Shah84c124d2010-04-09 08:31:19 +020026enum stat_type {
27 /* Total time spent (in ns) between request dispatch to the driver and
28 * request completion for IOs doen by this cgroup. This may not be
29 * accurate when NCQ is turned on. */
30 BLKIO_STAT_SERVICE_TIME = 0,
31 /* Total bytes transferred */
32 BLKIO_STAT_SERVICE_BYTES,
33 /* Total IOs serviced, post merge */
34 BLKIO_STAT_SERVICED,
35 /* Total time spent waiting in scheduler queue in ns */
36 BLKIO_STAT_WAIT_TIME,
Divyesh Shah812d4022010-04-08 21:14:23 -070037 /* Number of IOs merged */
38 BLKIO_STAT_MERGED,
Divyesh Shahcdc11842010-04-08 21:15:10 -070039 /* Number of IOs queued up */
40 BLKIO_STAT_QUEUED,
Divyesh Shah84c124d2010-04-09 08:31:19 +020041 /* All the single valued stats go below this */
42 BLKIO_STAT_TIME,
43 BLKIO_STAT_SECTORS,
44#ifdef CONFIG_DEBUG_BLK_CGROUP
Divyesh Shahcdc11842010-04-08 21:15:10 -070045 BLKIO_STAT_AVG_QUEUE_SIZE,
Divyesh Shah812df482010-04-08 21:15:35 -070046 BLKIO_STAT_IDLE_TIME,
47 BLKIO_STAT_EMPTY_TIME,
48 BLKIO_STAT_GROUP_WAIT_TIME,
Divyesh Shah84c124d2010-04-09 08:31:19 +020049 BLKIO_STAT_DEQUEUE
50#endif
51};
52
53enum stat_sub_type {
54 BLKIO_STAT_READ = 0,
55 BLKIO_STAT_WRITE,
56 BLKIO_STAT_SYNC,
57 BLKIO_STAT_ASYNC,
58 BLKIO_STAT_TOTAL
Divyesh Shah303a3ac2010-04-01 15:01:24 -070059};
60
Divyesh Shah812df482010-04-08 21:15:35 -070061/* blkg state flags */
62enum blkg_state_flags {
63 BLKG_waiting = 0,
64 BLKG_idling,
65 BLKG_empty,
66};
67
Vivek Goyal31e4c282009-12-03 12:59:42 -050068struct blkio_cgroup {
69 struct cgroup_subsys_state css;
70 unsigned int weight;
71 spinlock_t lock;
72 struct hlist_head blkg_list;
Gui Jianfeng34d0f172010-04-13 16:05:49 +080073 struct list_head policy_list; /* list of blkio_policy_node */
Vivek Goyal31e4c282009-12-03 12:59:42 -050074};
75
Divyesh Shah303a3ac2010-04-01 15:01:24 -070076struct blkio_group_stats {
77 /* total disk time and nr sectors dispatched by this group */
78 uint64_t time;
79 uint64_t sectors;
Divyesh Shahcdc11842010-04-08 21:15:10 -070080 uint64_t stat_arr[BLKIO_STAT_QUEUED + 1][BLKIO_STAT_TOTAL];
Divyesh Shah303a3ac2010-04-01 15:01:24 -070081#ifdef CONFIG_DEBUG_BLK_CGROUP
Divyesh Shahcdc11842010-04-08 21:15:10 -070082 /* Sum of number of IOs queued across all samples */
83 uint64_t avg_queue_size_sum;
84 /* Count of samples taken for average */
85 uint64_t avg_queue_size_samples;
Divyesh Shah303a3ac2010-04-01 15:01:24 -070086 /* How many times this group has been removed from service tree */
87 unsigned long dequeue;
Divyesh Shah812df482010-04-08 21:15:35 -070088
89 /* Total time spent waiting for it to be assigned a timeslice. */
90 uint64_t group_wait_time;
91 uint64_t start_group_wait_time;
92
93 /* Time spent idling for this blkio_group */
94 uint64_t idle_time;
95 uint64_t start_idle_time;
96 /*
97 * Total time when we have requests queued and do not contain the
98 * current active queue.
99 */
100 uint64_t empty_time;
101 uint64_t start_empty_time;
102 uint16_t flags;
Divyesh Shah303a3ac2010-04-01 15:01:24 -0700103#endif
104};
105
Vivek Goyal31e4c282009-12-03 12:59:42 -0500106struct blkio_group {
107 /* An rcu protected unique identifier for the group */
108 void *key;
109 struct hlist_node blkcg_node;
Vivek Goyalb1c35762009-12-03 12:59:47 -0500110 unsigned short blkcg_id;
Vivek Goyal2868ef72009-12-03 12:59:48 -0500111#ifdef CONFIG_DEBUG_BLK_CGROUP
112 /* Store cgroup path */
113 char path[128];
114#endif
Vivek Goyal22084192009-12-03 12:59:49 -0500115 /* The device MKDEV(major, minor), this group has been created for */
Divyesh Shah84c124d2010-04-09 08:31:19 +0200116 dev_t dev;
Vivek Goyal22084192009-12-03 12:59:49 -0500117
Divyesh Shah303a3ac2010-04-01 15:01:24 -0700118 /* Need to serialize the stats in the case of reset/update */
119 spinlock_t stats_lock;
120 struct blkio_group_stats stats;
Vivek Goyal31e4c282009-12-03 12:59:42 -0500121};
122
Gui Jianfeng34d0f172010-04-13 16:05:49 +0800123struct blkio_policy_node {
124 struct list_head node;
125 dev_t dev;
126 unsigned int weight;
127};
128
129extern unsigned int blkcg_get_weight(struct blkio_cgroup *blkcg,
130 dev_t dev);
131
Vivek Goyal3e252062009-12-04 10:36:42 -0500132typedef void (blkio_unlink_group_fn) (void *key, struct blkio_group *blkg);
133typedef void (blkio_update_group_weight_fn) (struct blkio_group *blkg,
134 unsigned int weight);
135
136struct blkio_policy_ops {
137 blkio_unlink_group_fn *blkio_unlink_group_fn;
138 blkio_update_group_weight_fn *blkio_update_group_weight_fn;
139};
140
141struct blkio_policy_type {
142 struct list_head list;
143 struct blkio_policy_ops ops;
144};
145
146/* Blkio controller policy registration */
147extern void blkio_policy_register(struct blkio_policy_type *);
148extern void blkio_policy_unregister(struct blkio_policy_type *);
149
Jens Axboe2f5ea472009-12-03 21:06:43 +0100150#else
151
152struct blkio_group {
153};
154
Vivek Goyal3e252062009-12-04 10:36:42 -0500155struct blkio_policy_type {
156};
157
158static inline void blkio_policy_register(struct blkio_policy_type *blkiop) { }
159static inline void blkio_policy_unregister(struct blkio_policy_type *blkiop) { }
160
Jens Axboe2f5ea472009-12-03 21:06:43 +0100161#endif
162
Vivek Goyal31e4c282009-12-03 12:59:42 -0500163#define BLKIO_WEIGHT_MIN 100
164#define BLKIO_WEIGHT_MAX 1000
165#define BLKIO_WEIGHT_DEFAULT 500
166
Vivek Goyal2868ef72009-12-03 12:59:48 -0500167#ifdef CONFIG_DEBUG_BLK_CGROUP
168static inline char *blkg_path(struct blkio_group *blkg)
169{
170 return blkg->path;
171}
Divyesh Shaha11cdaa2010-04-13 19:59:17 +0200172void blkiocg_update_avg_queue_size_stats(struct blkio_group *blkg);
Divyesh Shah91952912010-04-01 15:01:41 -0700173void blkiocg_update_dequeue_stats(struct blkio_group *blkg,
Vivek Goyal22084192009-12-03 12:59:49 -0500174 unsigned long dequeue);
Divyesh Shah812df482010-04-08 21:15:35 -0700175void blkiocg_update_set_idle_time_stats(struct blkio_group *blkg);
176void blkiocg_update_idle_time_stats(struct blkio_group *blkg);
Vivek Goyale5ff0822010-04-26 19:25:11 +0200177void blkiocg_set_start_empty_time(struct blkio_group *blkg);
Divyesh Shah812df482010-04-08 21:15:35 -0700178
179#define BLKG_FLAG_FNS(name) \
180static inline void blkio_mark_blkg_##name( \
181 struct blkio_group_stats *stats) \
182{ \
183 stats->flags |= (1 << BLKG_##name); \
184} \
185static inline void blkio_clear_blkg_##name( \
186 struct blkio_group_stats *stats) \
187{ \
188 stats->flags &= ~(1 << BLKG_##name); \
189} \
190static inline int blkio_blkg_##name(struct blkio_group_stats *stats) \
191{ \
192 return (stats->flags & (1 << BLKG_##name)) != 0; \
193} \
194
195BLKG_FLAG_FNS(waiting)
196BLKG_FLAG_FNS(idling)
197BLKG_FLAG_FNS(empty)
198#undef BLKG_FLAG_FNS
Vivek Goyal2868ef72009-12-03 12:59:48 -0500199#else
200static inline char *blkg_path(struct blkio_group *blkg) { return NULL; }
Divyesh Shaha11cdaa2010-04-13 19:59:17 +0200201static inline void blkiocg_update_avg_queue_size_stats(
Divyesh Shahcdc11842010-04-08 21:15:10 -0700202 struct blkio_group *blkg) {}
Divyesh Shah91952912010-04-01 15:01:41 -0700203static inline void blkiocg_update_dequeue_stats(struct blkio_group *blkg,
204 unsigned long dequeue) {}
Divyesh Shah812df482010-04-08 21:15:35 -0700205static inline void blkiocg_update_set_idle_time_stats(struct blkio_group *blkg)
206{}
207static inline void blkiocg_update_idle_time_stats(struct blkio_group *blkg) {}
Vivek Goyale5ff0822010-04-26 19:25:11 +0200208static inline void blkiocg_set_start_empty_time(struct blkio_group *blkg) {}
Vivek Goyal2868ef72009-12-03 12:59:48 -0500209#endif
210
Ben Blum67523c42010-03-10 15:22:11 -0800211#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
Vivek Goyal31e4c282009-12-03 12:59:42 -0500212extern struct blkio_cgroup blkio_root_cgroup;
213extern struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup);
214extern void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
Vivek Goyal22084192009-12-03 12:59:49 -0500215 struct blkio_group *blkg, void *key, dev_t dev);
Vivek Goyal31e4c282009-12-03 12:59:42 -0500216extern int blkiocg_del_blkio_group(struct blkio_group *blkg);
217extern struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg,
218 void *key);
Divyesh Shah303a3ac2010-04-01 15:01:24 -0700219void blkiocg_update_timeslice_used(struct blkio_group *blkg,
220 unsigned long time);
Divyesh Shah84c124d2010-04-09 08:31:19 +0200221void blkiocg_update_dispatch_stats(struct blkio_group *blkg, uint64_t bytes,
222 bool direction, bool sync);
223void blkiocg_update_completion_stats(struct blkio_group *blkg,
224 uint64_t start_time, uint64_t io_start_time, bool direction, bool sync);
Divyesh Shah812d4022010-04-08 21:14:23 -0700225void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction,
226 bool sync);
Divyesh Shaha11cdaa2010-04-13 19:59:17 +0200227void blkiocg_update_io_add_stats(struct blkio_group *blkg,
Divyesh Shahcdc11842010-04-08 21:15:10 -0700228 struct blkio_group *curr_blkg, bool direction, bool sync);
Divyesh Shaha11cdaa2010-04-13 19:59:17 +0200229void blkiocg_update_io_remove_stats(struct blkio_group *blkg,
Divyesh Shahcdc11842010-04-08 21:15:10 -0700230 bool direction, bool sync);
Vivek Goyal31e4c282009-12-03 12:59:42 -0500231#else
Jens Axboe2f5ea472009-12-03 21:06:43 +0100232struct cgroup;
Vivek Goyal31e4c282009-12-03 12:59:42 -0500233static inline struct blkio_cgroup *
234cgroup_to_blkio_cgroup(struct cgroup *cgroup) { return NULL; }
235
236static inline void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
Divyesh Shah84c124d2010-04-09 08:31:19 +0200237 struct blkio_group *blkg, void *key, dev_t dev) {}
Vivek Goyal31e4c282009-12-03 12:59:42 -0500238
239static inline int
240blkiocg_del_blkio_group(struct blkio_group *blkg) { return 0; }
241
242static inline struct blkio_group *
243blkiocg_lookup_group(struct blkio_cgroup *blkcg, void *key) { return NULL; }
Divyesh Shah303a3ac2010-04-01 15:01:24 -0700244static inline void blkiocg_update_timeslice_used(struct blkio_group *blkg,
Divyesh Shah9a0785b2010-04-01 15:01:04 -0700245 unsigned long time) {}
Divyesh Shah84c124d2010-04-09 08:31:19 +0200246static inline void blkiocg_update_dispatch_stats(struct blkio_group *blkg,
247 uint64_t bytes, bool direction, bool sync) {}
248static inline void blkiocg_update_completion_stats(struct blkio_group *blkg,
249 uint64_t start_time, uint64_t io_start_time, bool direction,
250 bool sync) {}
Divyesh Shah812d4022010-04-08 21:14:23 -0700251static inline void blkiocg_update_io_merged_stats(struct blkio_group *blkg,
252 bool direction, bool sync) {}
Divyesh Shaha11cdaa2010-04-13 19:59:17 +0200253static inline void blkiocg_update_io_add_stats(struct blkio_group *blkg,
Divyesh Shahcdc11842010-04-08 21:15:10 -0700254 struct blkio_group *curr_blkg, bool direction, bool sync) {}
Divyesh Shaha11cdaa2010-04-13 19:59:17 +0200255static inline void blkiocg_update_io_remove_stats(struct blkio_group *blkg,
Divyesh Shahcdc11842010-04-08 21:15:10 -0700256 bool direction, bool sync) {}
Vivek Goyal31e4c282009-12-03 12:59:42 -0500257#endif
258#endif /* _BLK_CGROUP_H */