Commit | Line | Data |
---|---|---|
31e4c28d VG |
1 | /* |
2 | * Common Block IO controller cgroup interface | |
3 | * | |
4 | * Based on ideas and code from CFQ, CFS and BFQ: | |
5 | * Copyright (C) 2003 Jens Axboe <axboe@kernel.dk> | |
6 | * | |
7 | * Copyright (C) 2008 Fabio Checconi <fabio@gandalf.sssup.it> | |
8 | * Paolo Valente <paolo.valente@unimore.it> | |
9 | * | |
10 | * Copyright (C) 2009 Vivek Goyal <vgoyal@redhat.com> | |
11 | * Nauman Rafique <nauman@google.com> | |
12 | */ | |
13 | #include <linux/ioprio.h> | |
22084190 VG |
14 | #include <linux/seq_file.h> |
15 | #include <linux/kdev_t.h> | |
9d6a986c | 16 | #include <linux/module.h> |
accee785 | 17 | #include <linux/err.h> |
9195291e | 18 | #include <linux/blkdev.h> |
5a0e3ad6 | 19 | #include <linux/slab.h> |
31e4c28d | 20 | #include "blk-cgroup.h" |
34d0f179 | 21 | #include <linux/genhd.h> |
3e252066 | 22 | |
84c124da DS |
23 | #define MAX_KEY_LEN 100 |
24 | ||
3e252066 VG |
25 | static DEFINE_SPINLOCK(blkio_list_lock); |
26 | static LIST_HEAD(blkio_list); | |
b1c35769 | 27 | |
31e4c28d | 28 | struct blkio_cgroup blkio_root_cgroup = { .weight = 2*BLKIO_WEIGHT_DEFAULT }; |
9d6a986c VG |
29 | EXPORT_SYMBOL_GPL(blkio_root_cgroup); |
30 | ||
67523c48 BB |
31 | static struct cgroup_subsys_state *blkiocg_create(struct cgroup_subsys *, |
32 | struct cgroup *); | |
33 | static int blkiocg_can_attach(struct cgroup_subsys *, struct cgroup *, | |
34 | struct task_struct *, bool); | |
35 | static void blkiocg_attach(struct cgroup_subsys *, struct cgroup *, | |
36 | struct cgroup *, struct task_struct *, bool); | |
37 | static void blkiocg_destroy(struct cgroup_subsys *, struct cgroup *); | |
38 | static int blkiocg_populate(struct cgroup_subsys *, struct cgroup *); | |
39 | ||
062a644d VG |
40 | /* for encoding cft->private value on file */ |
41 | #define BLKIOFILE_PRIVATE(x, val) (((x) << 16) | (val)) | |
42 | /* What policy owns the file, proportional or throttle */ | |
43 | #define BLKIOFILE_POLICY(val) (((val) >> 16) & 0xffff) | |
44 | #define BLKIOFILE_ATTR(val) ((val) & 0xffff) | |
45 | ||
67523c48 BB |
46 | struct cgroup_subsys blkio_subsys = { |
47 | .name = "blkio", | |
48 | .create = blkiocg_create, | |
49 | .can_attach = blkiocg_can_attach, | |
50 | .attach = blkiocg_attach, | |
51 | .destroy = blkiocg_destroy, | |
52 | .populate = blkiocg_populate, | |
53 | #ifdef CONFIG_BLK_CGROUP | |
54 | /* note: blkio_subsys_id is otherwise defined in blk-cgroup.h */ | |
55 | .subsys_id = blkio_subsys_id, | |
56 | #endif | |
57 | .use_id = 1, | |
58 | .module = THIS_MODULE, | |
59 | }; | |
60 | EXPORT_SYMBOL_GPL(blkio_subsys); | |
61 | ||
34d0f179 GJ |
62 | static inline void blkio_policy_insert_node(struct blkio_cgroup *blkcg, |
63 | struct blkio_policy_node *pn) | |
64 | { | |
65 | list_add(&pn->node, &blkcg->policy_list); | |
66 | } | |
67 | ||
062a644d VG |
68 | static inline bool cftype_blkg_same_policy(struct cftype *cft, |
69 | struct blkio_group *blkg) | |
70 | { | |
71 | enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); | |
72 | ||
73 | if (blkg->plid == plid) | |
74 | return 1; | |
75 | ||
76 | return 0; | |
77 | } | |
78 | ||
79 | /* Determines if policy node matches cgroup file being accessed */ | |
80 | static inline bool pn_matches_cftype(struct cftype *cft, | |
81 | struct blkio_policy_node *pn) | |
82 | { | |
83 | enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); | |
84 | int fileid = BLKIOFILE_ATTR(cft->private); | |
85 | ||
86 | return (plid == pn->plid && fileid == pn->fileid); | |
87 | } | |
88 | ||
34d0f179 GJ |
89 | /* Must be called with blkcg->lock held */ |
90 | static inline void blkio_policy_delete_node(struct blkio_policy_node *pn) | |
91 | { | |
92 | list_del(&pn->node); | |
93 | } | |
94 | ||
95 | /* Must be called with blkcg->lock held */ | |
96 | static struct blkio_policy_node * | |
062a644d VG |
97 | blkio_policy_search_node(const struct blkio_cgroup *blkcg, dev_t dev, |
98 | enum blkio_policy_id plid, int fileid) | |
34d0f179 GJ |
99 | { |
100 | struct blkio_policy_node *pn; | |
101 | ||
102 | list_for_each_entry(pn, &blkcg->policy_list, node) { | |
062a644d | 103 | if (pn->dev == dev && pn->plid == plid && pn->fileid == fileid) |
34d0f179 GJ |
104 | return pn; |
105 | } | |
106 | ||
107 | return NULL; | |
108 | } | |
109 | ||
31e4c28d VG |
110 | struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup) |
111 | { | |
112 | return container_of(cgroup_subsys_state(cgroup, blkio_subsys_id), | |
113 | struct blkio_cgroup, css); | |
114 | } | |
9d6a986c | 115 | EXPORT_SYMBOL_GPL(cgroup_to_blkio_cgroup); |
31e4c28d | 116 | |
062a644d VG |
117 | static inline void |
118 | blkio_update_group_weight(struct blkio_group *blkg, unsigned int weight) | |
119 | { | |
120 | struct blkio_policy_type *blkiop; | |
121 | ||
122 | list_for_each_entry(blkiop, &blkio_list, list) { | |
123 | /* If this policy does not own the blkg, do not send updates */ | |
124 | if (blkiop->plid != blkg->plid) | |
125 | continue; | |
126 | if (blkiop->ops.blkio_update_group_weight_fn) | |
fe071437 VG |
127 | blkiop->ops.blkio_update_group_weight_fn(blkg->key, |
128 | blkg, weight); | |
062a644d VG |
129 | } |
130 | } | |
131 | ||
4c9eefa1 VG |
132 | static inline void blkio_update_group_bps(struct blkio_group *blkg, u64 bps, |
133 | int fileid) | |
134 | { | |
135 | struct blkio_policy_type *blkiop; | |
136 | ||
137 | list_for_each_entry(blkiop, &blkio_list, list) { | |
138 | ||
139 | /* If this policy does not own the blkg, do not send updates */ | |
140 | if (blkiop->plid != blkg->plid) | |
141 | continue; | |
142 | ||
143 | if (fileid == BLKIO_THROTL_read_bps_device | |
144 | && blkiop->ops.blkio_update_group_read_bps_fn) | |
fe071437 VG |
145 | blkiop->ops.blkio_update_group_read_bps_fn(blkg->key, |
146 | blkg, bps); | |
4c9eefa1 VG |
147 | |
148 | if (fileid == BLKIO_THROTL_write_bps_device | |
149 | && blkiop->ops.blkio_update_group_write_bps_fn) | |
fe071437 VG |
150 | blkiop->ops.blkio_update_group_write_bps_fn(blkg->key, |
151 | blkg, bps); | |
4c9eefa1 VG |
152 | } |
153 | } | |
154 | ||
7702e8f4 VG |
155 | static inline void blkio_update_group_iops(struct blkio_group *blkg, |
156 | unsigned int iops, int fileid) | |
157 | { | |
158 | struct blkio_policy_type *blkiop; | |
159 | ||
160 | list_for_each_entry(blkiop, &blkio_list, list) { | |
161 | ||
162 | /* If this policy does not own the blkg, do not send updates */ | |
163 | if (blkiop->plid != blkg->plid) | |
164 | continue; | |
165 | ||
166 | if (fileid == BLKIO_THROTL_read_iops_device | |
167 | && blkiop->ops.blkio_update_group_read_iops_fn) | |
fe071437 VG |
168 | blkiop->ops.blkio_update_group_read_iops_fn(blkg->key, |
169 | blkg, iops); | |
7702e8f4 VG |
170 | |
171 | if (fileid == BLKIO_THROTL_write_iops_device | |
172 | && blkiop->ops.blkio_update_group_write_iops_fn) | |
fe071437 VG |
173 | blkiop->ops.blkio_update_group_write_iops_fn(blkg->key, |
174 | blkg,iops); | |
7702e8f4 VG |
175 | } |
176 | } | |
177 | ||
9195291e DS |
178 | /* |
179 | * Add to the appropriate stat variable depending on the request type. | |
180 | * This should be called with the blkg->stats_lock held. | |
181 | */ | |
84c124da DS |
182 | static void blkio_add_stat(uint64_t *stat, uint64_t add, bool direction, |
183 | bool sync) | |
9195291e | 184 | { |
84c124da DS |
185 | if (direction) |
186 | stat[BLKIO_STAT_WRITE] += add; | |
9195291e | 187 | else |
84c124da DS |
188 | stat[BLKIO_STAT_READ] += add; |
189 | if (sync) | |
190 | stat[BLKIO_STAT_SYNC] += add; | |
9195291e | 191 | else |
84c124da | 192 | stat[BLKIO_STAT_ASYNC] += add; |
9195291e DS |
193 | } |
194 | ||
cdc1184c DS |
195 | /* |
196 | * Decrements the appropriate stat variable if non-zero depending on the | |
197 | * request type. Panics on value being zero. | |
198 | * This should be called with the blkg->stats_lock held. | |
199 | */ | |
200 | static void blkio_check_and_dec_stat(uint64_t *stat, bool direction, bool sync) | |
201 | { | |
202 | if (direction) { | |
203 | BUG_ON(stat[BLKIO_STAT_WRITE] == 0); | |
204 | stat[BLKIO_STAT_WRITE]--; | |
205 | } else { | |
206 | BUG_ON(stat[BLKIO_STAT_READ] == 0); | |
207 | stat[BLKIO_STAT_READ]--; | |
208 | } | |
209 | if (sync) { | |
210 | BUG_ON(stat[BLKIO_STAT_SYNC] == 0); | |
211 | stat[BLKIO_STAT_SYNC]--; | |
212 | } else { | |
213 | BUG_ON(stat[BLKIO_STAT_ASYNC] == 0); | |
214 | stat[BLKIO_STAT_ASYNC]--; | |
215 | } | |
216 | } | |
217 | ||
218 | #ifdef CONFIG_DEBUG_BLK_CGROUP | |
812df48d DS |
219 | /* This should be called with the blkg->stats_lock held. */ |
220 | static void blkio_set_start_group_wait_time(struct blkio_group *blkg, | |
221 | struct blkio_group *curr_blkg) | |
222 | { | |
223 | if (blkio_blkg_waiting(&blkg->stats)) | |
224 | return; | |
225 | if (blkg == curr_blkg) | |
226 | return; | |
227 | blkg->stats.start_group_wait_time = sched_clock(); | |
228 | blkio_mark_blkg_waiting(&blkg->stats); | |
229 | } | |
230 | ||
231 | /* This should be called with the blkg->stats_lock held. */ | |
232 | static void blkio_update_group_wait_time(struct blkio_group_stats *stats) | |
233 | { | |
234 | unsigned long long now; | |
235 | ||
236 | if (!blkio_blkg_waiting(stats)) | |
237 | return; | |
238 | ||
239 | now = sched_clock(); | |
240 | if (time_after64(now, stats->start_group_wait_time)) | |
241 | stats->group_wait_time += now - stats->start_group_wait_time; | |
242 | blkio_clear_blkg_waiting(stats); | |
243 | } | |
244 | ||
245 | /* This should be called with the blkg->stats_lock held. */ | |
246 | static void blkio_end_empty_time(struct blkio_group_stats *stats) | |
247 | { | |
248 | unsigned long long now; | |
249 | ||
250 | if (!blkio_blkg_empty(stats)) | |
251 | return; | |
252 | ||
253 | now = sched_clock(); | |
254 | if (time_after64(now, stats->start_empty_time)) | |
255 | stats->empty_time += now - stats->start_empty_time; | |
256 | blkio_clear_blkg_empty(stats); | |
257 | } | |
258 | ||
259 | void blkiocg_update_set_idle_time_stats(struct blkio_group *blkg) | |
260 | { | |
261 | unsigned long flags; | |
262 | ||
263 | spin_lock_irqsave(&blkg->stats_lock, flags); | |
264 | BUG_ON(blkio_blkg_idling(&blkg->stats)); | |
265 | blkg->stats.start_idle_time = sched_clock(); | |
266 | blkio_mark_blkg_idling(&blkg->stats); | |
267 | spin_unlock_irqrestore(&blkg->stats_lock, flags); | |
268 | } | |
269 | EXPORT_SYMBOL_GPL(blkiocg_update_set_idle_time_stats); | |
270 | ||
271 | void blkiocg_update_idle_time_stats(struct blkio_group *blkg) | |
272 | { | |
273 | unsigned long flags; | |
274 | unsigned long long now; | |
275 | struct blkio_group_stats *stats; | |
276 | ||
277 | spin_lock_irqsave(&blkg->stats_lock, flags); | |
278 | stats = &blkg->stats; | |
279 | if (blkio_blkg_idling(stats)) { | |
280 | now = sched_clock(); | |
281 | if (time_after64(now, stats->start_idle_time)) | |
282 | stats->idle_time += now - stats->start_idle_time; | |
283 | blkio_clear_blkg_idling(stats); | |
284 | } | |
285 | spin_unlock_irqrestore(&blkg->stats_lock, flags); | |
286 | } | |
287 | EXPORT_SYMBOL_GPL(blkiocg_update_idle_time_stats); | |
288 | ||
a11cdaa7 | 289 | void blkiocg_update_avg_queue_size_stats(struct blkio_group *blkg) |
cdc1184c DS |
290 | { |
291 | unsigned long flags; | |
292 | struct blkio_group_stats *stats; | |
293 | ||
294 | spin_lock_irqsave(&blkg->stats_lock, flags); | |
295 | stats = &blkg->stats; | |
296 | stats->avg_queue_size_sum += | |
297 | stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_READ] + | |
298 | stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_WRITE]; | |
299 | stats->avg_queue_size_samples++; | |
812df48d | 300 | blkio_update_group_wait_time(stats); |
cdc1184c DS |
301 | spin_unlock_irqrestore(&blkg->stats_lock, flags); |
302 | } | |
a11cdaa7 DS |
303 | EXPORT_SYMBOL_GPL(blkiocg_update_avg_queue_size_stats); |
304 | ||
e5ff082e | 305 | void blkiocg_set_start_empty_time(struct blkio_group *blkg) |
28baf442 DS |
306 | { |
307 | unsigned long flags; | |
308 | struct blkio_group_stats *stats; | |
309 | ||
310 | spin_lock_irqsave(&blkg->stats_lock, flags); | |
311 | stats = &blkg->stats; | |
312 | ||
313 | if (stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_READ] || | |
314 | stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_WRITE]) { | |
315 | spin_unlock_irqrestore(&blkg->stats_lock, flags); | |
316 | return; | |
317 | } | |
318 | ||
319 | /* | |
e5ff082e VG |
320 | * group is already marked empty. This can happen if cfqq got new |
321 | * request in parent group and moved to this group while being added | |
322 | * to service tree. Just ignore the event and move on. | |
28baf442 | 323 | */ |
e5ff082e VG |
324 | if(blkio_blkg_empty(stats)) { |
325 | spin_unlock_irqrestore(&blkg->stats_lock, flags); | |
326 | return; | |
327 | } | |
328 | ||
28baf442 DS |
329 | stats->start_empty_time = sched_clock(); |
330 | blkio_mark_blkg_empty(stats); | |
331 | spin_unlock_irqrestore(&blkg->stats_lock, flags); | |
332 | } | |
333 | EXPORT_SYMBOL_GPL(blkiocg_set_start_empty_time); | |
334 | ||
a11cdaa7 DS |
335 | void blkiocg_update_dequeue_stats(struct blkio_group *blkg, |
336 | unsigned long dequeue) | |
337 | { | |
338 | blkg->stats.dequeue += dequeue; | |
339 | } | |
340 | EXPORT_SYMBOL_GPL(blkiocg_update_dequeue_stats); | |
812df48d DS |
341 | #else |
342 | static inline void blkio_set_start_group_wait_time(struct blkio_group *blkg, | |
343 | struct blkio_group *curr_blkg) {} | |
344 | static inline void blkio_end_empty_time(struct blkio_group_stats *stats) {} | |
cdc1184c DS |
345 | #endif |
346 | ||
a11cdaa7 | 347 | void blkiocg_update_io_add_stats(struct blkio_group *blkg, |
cdc1184c DS |
348 | struct blkio_group *curr_blkg, bool direction, |
349 | bool sync) | |
350 | { | |
351 | unsigned long flags; | |
352 | ||
353 | spin_lock_irqsave(&blkg->stats_lock, flags); | |
354 | blkio_add_stat(blkg->stats.stat_arr[BLKIO_STAT_QUEUED], 1, direction, | |
355 | sync); | |
812df48d DS |
356 | blkio_end_empty_time(&blkg->stats); |
357 | blkio_set_start_group_wait_time(blkg, curr_blkg); | |
cdc1184c DS |
358 | spin_unlock_irqrestore(&blkg->stats_lock, flags); |
359 | } | |
a11cdaa7 | 360 | EXPORT_SYMBOL_GPL(blkiocg_update_io_add_stats); |
cdc1184c | 361 | |
a11cdaa7 | 362 | void blkiocg_update_io_remove_stats(struct blkio_group *blkg, |
cdc1184c DS |
363 | bool direction, bool sync) |
364 | { | |
365 | unsigned long flags; | |
366 | ||
367 | spin_lock_irqsave(&blkg->stats_lock, flags); | |
368 | blkio_check_and_dec_stat(blkg->stats.stat_arr[BLKIO_STAT_QUEUED], | |
369 | direction, sync); | |
370 | spin_unlock_irqrestore(&blkg->stats_lock, flags); | |
371 | } | |
a11cdaa7 | 372 | EXPORT_SYMBOL_GPL(blkiocg_update_io_remove_stats); |
cdc1184c | 373 | |
303a3acb | 374 | void blkiocg_update_timeslice_used(struct blkio_group *blkg, unsigned long time) |
22084190 | 375 | { |
303a3acb DS |
376 | unsigned long flags; |
377 | ||
378 | spin_lock_irqsave(&blkg->stats_lock, flags); | |
379 | blkg->stats.time += time; | |
380 | spin_unlock_irqrestore(&blkg->stats_lock, flags); | |
22084190 | 381 | } |
303a3acb | 382 | EXPORT_SYMBOL_GPL(blkiocg_update_timeslice_used); |
22084190 | 383 | |
84c124da DS |
384 | void blkiocg_update_dispatch_stats(struct blkio_group *blkg, |
385 | uint64_t bytes, bool direction, bool sync) | |
9195291e DS |
386 | { |
387 | struct blkio_group_stats *stats; | |
388 | unsigned long flags; | |
389 | ||
390 | spin_lock_irqsave(&blkg->stats_lock, flags); | |
391 | stats = &blkg->stats; | |
84c124da DS |
392 | stats->sectors += bytes >> 9; |
393 | blkio_add_stat(stats->stat_arr[BLKIO_STAT_SERVICED], 1, direction, | |
394 | sync); | |
395 | blkio_add_stat(stats->stat_arr[BLKIO_STAT_SERVICE_BYTES], bytes, | |
396 | direction, sync); | |
9195291e DS |
397 | spin_unlock_irqrestore(&blkg->stats_lock, flags); |
398 | } | |
84c124da | 399 | EXPORT_SYMBOL_GPL(blkiocg_update_dispatch_stats); |
9195291e | 400 | |
84c124da DS |
401 | void blkiocg_update_completion_stats(struct blkio_group *blkg, |
402 | uint64_t start_time, uint64_t io_start_time, bool direction, bool sync) | |
9195291e DS |
403 | { |
404 | struct blkio_group_stats *stats; | |
405 | unsigned long flags; | |
406 | unsigned long long now = sched_clock(); | |
407 | ||
408 | spin_lock_irqsave(&blkg->stats_lock, flags); | |
409 | stats = &blkg->stats; | |
84c124da DS |
410 | if (time_after64(now, io_start_time)) |
411 | blkio_add_stat(stats->stat_arr[BLKIO_STAT_SERVICE_TIME], | |
412 | now - io_start_time, direction, sync); | |
413 | if (time_after64(io_start_time, start_time)) | |
414 | blkio_add_stat(stats->stat_arr[BLKIO_STAT_WAIT_TIME], | |
415 | io_start_time - start_time, direction, sync); | |
9195291e DS |
416 | spin_unlock_irqrestore(&blkg->stats_lock, flags); |
417 | } | |
84c124da | 418 | EXPORT_SYMBOL_GPL(blkiocg_update_completion_stats); |
9195291e | 419 | |
812d4026 DS |
420 | void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction, |
421 | bool sync) | |
422 | { | |
423 | unsigned long flags; | |
424 | ||
425 | spin_lock_irqsave(&blkg->stats_lock, flags); | |
426 | blkio_add_stat(blkg->stats.stat_arr[BLKIO_STAT_MERGED], 1, direction, | |
427 | sync); | |
428 | spin_unlock_irqrestore(&blkg->stats_lock, flags); | |
429 | } | |
430 | EXPORT_SYMBOL_GPL(blkiocg_update_io_merged_stats); | |
431 | ||
31e4c28d | 432 | void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg, |
062a644d VG |
433 | struct blkio_group *blkg, void *key, dev_t dev, |
434 | enum blkio_policy_id plid) | |
31e4c28d VG |
435 | { |
436 | unsigned long flags; | |
437 | ||
438 | spin_lock_irqsave(&blkcg->lock, flags); | |
8d2a91f8 | 439 | spin_lock_init(&blkg->stats_lock); |
31e4c28d | 440 | rcu_assign_pointer(blkg->key, key); |
b1c35769 | 441 | blkg->blkcg_id = css_id(&blkcg->css); |
31e4c28d | 442 | hlist_add_head_rcu(&blkg->blkcg_node, &blkcg->blkg_list); |
062a644d | 443 | blkg->plid = plid; |
31e4c28d | 444 | spin_unlock_irqrestore(&blkcg->lock, flags); |
2868ef7b VG |
445 | /* Need to take css reference ? */ |
446 | cgroup_path(blkcg->css.cgroup, blkg->path, sizeof(blkg->path)); | |
22084190 | 447 | blkg->dev = dev; |
31e4c28d | 448 | } |
9d6a986c | 449 | EXPORT_SYMBOL_GPL(blkiocg_add_blkio_group); |
31e4c28d | 450 | |
b1c35769 VG |
451 | static void __blkiocg_del_blkio_group(struct blkio_group *blkg) |
452 | { | |
453 | hlist_del_init_rcu(&blkg->blkcg_node); | |
454 | blkg->blkcg_id = 0; | |
455 | } | |
456 | ||
457 | /* | |
458 | * returns 0 if blkio_group was still on cgroup list. Otherwise returns 1 | |
459 | * indicating that blk_group was unhashed by the time we got to it. | |
460 | */ | |
31e4c28d VG |
461 | int blkiocg_del_blkio_group(struct blkio_group *blkg) |
462 | { | |
b1c35769 VG |
463 | struct blkio_cgroup *blkcg; |
464 | unsigned long flags; | |
465 | struct cgroup_subsys_state *css; | |
466 | int ret = 1; | |
467 | ||
468 | rcu_read_lock(); | |
469 | css = css_lookup(&blkio_subsys, blkg->blkcg_id); | |
0f3942a3 JA |
470 | if (css) { |
471 | blkcg = container_of(css, struct blkio_cgroup, css); | |
472 | spin_lock_irqsave(&blkcg->lock, flags); | |
473 | if (!hlist_unhashed(&blkg->blkcg_node)) { | |
474 | __blkiocg_del_blkio_group(blkg); | |
475 | ret = 0; | |
476 | } | |
477 | spin_unlock_irqrestore(&blkcg->lock, flags); | |
b1c35769 | 478 | } |
0f3942a3 | 479 | |
b1c35769 VG |
480 | rcu_read_unlock(); |
481 | return ret; | |
31e4c28d | 482 | } |
9d6a986c | 483 | EXPORT_SYMBOL_GPL(blkiocg_del_blkio_group); |
31e4c28d VG |
484 | |
485 | /* called under rcu_read_lock(). */ | |
486 | struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg, void *key) | |
487 | { | |
488 | struct blkio_group *blkg; | |
489 | struct hlist_node *n; | |
490 | void *__key; | |
491 | ||
492 | hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) { | |
493 | __key = blkg->key; | |
494 | if (__key == key) | |
495 | return blkg; | |
496 | } | |
497 | ||
498 | return NULL; | |
499 | } | |
9d6a986c | 500 | EXPORT_SYMBOL_GPL(blkiocg_lookup_group); |
31e4c28d | 501 | |
303a3acb | 502 | static int |
84c124da | 503 | blkiocg_reset_stats(struct cgroup *cgroup, struct cftype *cftype, u64 val) |
303a3acb DS |
504 | { |
505 | struct blkio_cgroup *blkcg; | |
506 | struct blkio_group *blkg; | |
812df48d | 507 | struct blkio_group_stats *stats; |
303a3acb | 508 | struct hlist_node *n; |
cdc1184c DS |
509 | uint64_t queued[BLKIO_STAT_TOTAL]; |
510 | int i; | |
812df48d DS |
511 | #ifdef CONFIG_DEBUG_BLK_CGROUP |
512 | bool idling, waiting, empty; | |
513 | unsigned long long now = sched_clock(); | |
514 | #endif | |
303a3acb DS |
515 | |
516 | blkcg = cgroup_to_blkio_cgroup(cgroup); | |
517 | spin_lock_irq(&blkcg->lock); | |
518 | hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) { | |
519 | spin_lock(&blkg->stats_lock); | |
812df48d DS |
520 | stats = &blkg->stats; |
521 | #ifdef CONFIG_DEBUG_BLK_CGROUP | |
522 | idling = blkio_blkg_idling(stats); | |
523 | waiting = blkio_blkg_waiting(stats); | |
524 | empty = blkio_blkg_empty(stats); | |
525 | #endif | |
cdc1184c | 526 | for (i = 0; i < BLKIO_STAT_TOTAL; i++) |
812df48d DS |
527 | queued[i] = stats->stat_arr[BLKIO_STAT_QUEUED][i]; |
528 | memset(stats, 0, sizeof(struct blkio_group_stats)); | |
cdc1184c | 529 | for (i = 0; i < BLKIO_STAT_TOTAL; i++) |
812df48d DS |
530 | stats->stat_arr[BLKIO_STAT_QUEUED][i] = queued[i]; |
531 | #ifdef CONFIG_DEBUG_BLK_CGROUP | |
532 | if (idling) { | |
533 | blkio_mark_blkg_idling(stats); | |
534 | stats->start_idle_time = now; | |
535 | } | |
536 | if (waiting) { | |
537 | blkio_mark_blkg_waiting(stats); | |
538 | stats->start_group_wait_time = now; | |
539 | } | |
540 | if (empty) { | |
541 | blkio_mark_blkg_empty(stats); | |
542 | stats->start_empty_time = now; | |
543 | } | |
544 | #endif | |
303a3acb DS |
545 | spin_unlock(&blkg->stats_lock); |
546 | } | |
547 | spin_unlock_irq(&blkcg->lock); | |
548 | return 0; | |
549 | } | |
550 | ||
84c124da DS |
551 | static void blkio_get_key_name(enum stat_sub_type type, dev_t dev, char *str, |
552 | int chars_left, bool diskname_only) | |
303a3acb | 553 | { |
84c124da | 554 | snprintf(str, chars_left, "%d:%d", MAJOR(dev), MINOR(dev)); |
303a3acb DS |
555 | chars_left -= strlen(str); |
556 | if (chars_left <= 0) { | |
557 | printk(KERN_WARNING | |
558 | "Possibly incorrect cgroup stat display format"); | |
559 | return; | |
560 | } | |
84c124da DS |
561 | if (diskname_only) |
562 | return; | |
303a3acb | 563 | switch (type) { |
84c124da | 564 | case BLKIO_STAT_READ: |
303a3acb DS |
565 | strlcat(str, " Read", chars_left); |
566 | break; | |
84c124da | 567 | case BLKIO_STAT_WRITE: |
303a3acb DS |
568 | strlcat(str, " Write", chars_left); |
569 | break; | |
84c124da | 570 | case BLKIO_STAT_SYNC: |
303a3acb DS |
571 | strlcat(str, " Sync", chars_left); |
572 | break; | |
84c124da | 573 | case BLKIO_STAT_ASYNC: |
303a3acb DS |
574 | strlcat(str, " Async", chars_left); |
575 | break; | |
84c124da | 576 | case BLKIO_STAT_TOTAL: |
303a3acb DS |
577 | strlcat(str, " Total", chars_left); |
578 | break; | |
579 | default: | |
580 | strlcat(str, " Invalid", chars_left); | |
581 | } | |
582 | } | |
583 | ||
84c124da DS |
584 | static uint64_t blkio_fill_stat(char *str, int chars_left, uint64_t val, |
585 | struct cgroup_map_cb *cb, dev_t dev) | |
586 | { | |
587 | blkio_get_key_name(0, dev, str, chars_left, true); | |
588 | cb->fill(cb, str, val); | |
589 | return val; | |
590 | } | |
303a3acb | 591 | |
84c124da DS |
592 | /* This should be called with blkg->stats_lock held */ |
593 | static uint64_t blkio_get_stat(struct blkio_group *blkg, | |
594 | struct cgroup_map_cb *cb, dev_t dev, enum stat_type type) | |
303a3acb DS |
595 | { |
596 | uint64_t disk_total; | |
597 | char key_str[MAX_KEY_LEN]; | |
84c124da DS |
598 | enum stat_sub_type sub_type; |
599 | ||
600 | if (type == BLKIO_STAT_TIME) | |
601 | return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, | |
602 | blkg->stats.time, cb, dev); | |
603 | if (type == BLKIO_STAT_SECTORS) | |
604 | return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, | |
605 | blkg->stats.sectors, cb, dev); | |
606 | #ifdef CONFIG_DEBUG_BLK_CGROUP | |
cdc1184c DS |
607 | if (type == BLKIO_STAT_AVG_QUEUE_SIZE) { |
608 | uint64_t sum = blkg->stats.avg_queue_size_sum; | |
609 | uint64_t samples = blkg->stats.avg_queue_size_samples; | |
610 | if (samples) | |
611 | do_div(sum, samples); | |
612 | else | |
613 | sum = 0; | |
614 | return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, sum, cb, dev); | |
615 | } | |
812df48d DS |
616 | if (type == BLKIO_STAT_GROUP_WAIT_TIME) |
617 | return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, | |
618 | blkg->stats.group_wait_time, cb, dev); | |
619 | if (type == BLKIO_STAT_IDLE_TIME) | |
620 | return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, | |
621 | blkg->stats.idle_time, cb, dev); | |
622 | if (type == BLKIO_STAT_EMPTY_TIME) | |
623 | return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, | |
624 | blkg->stats.empty_time, cb, dev); | |
84c124da DS |
625 | if (type == BLKIO_STAT_DEQUEUE) |
626 | return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, | |
627 | blkg->stats.dequeue, cb, dev); | |
628 | #endif | |
303a3acb | 629 | |
84c124da DS |
630 | for (sub_type = BLKIO_STAT_READ; sub_type < BLKIO_STAT_TOTAL; |
631 | sub_type++) { | |
632 | blkio_get_key_name(sub_type, dev, key_str, MAX_KEY_LEN, false); | |
633 | cb->fill(cb, key_str, blkg->stats.stat_arr[type][sub_type]); | |
303a3acb | 634 | } |
84c124da DS |
635 | disk_total = blkg->stats.stat_arr[type][BLKIO_STAT_READ] + |
636 | blkg->stats.stat_arr[type][BLKIO_STAT_WRITE]; | |
637 | blkio_get_key_name(BLKIO_STAT_TOTAL, dev, key_str, MAX_KEY_LEN, false); | |
303a3acb DS |
638 | cb->fill(cb, key_str, disk_total); |
639 | return disk_total; | |
640 | } | |
641 | ||
34d0f179 GJ |
642 | static int blkio_check_dev_num(dev_t dev) |
643 | { | |
644 | int part = 0; | |
645 | struct gendisk *disk; | |
646 | ||
647 | disk = get_gendisk(dev, &part); | |
648 | if (!disk || part) | |
649 | return -ENODEV; | |
650 | ||
651 | return 0; | |
652 | } | |
653 | ||
654 | static int blkio_policy_parse_and_set(char *buf, | |
062a644d | 655 | struct blkio_policy_node *newpn, enum blkio_policy_id plid, int fileid) |
34d0f179 GJ |
656 | { |
657 | char *s[4], *p, *major_s = NULL, *minor_s = NULL; | |
658 | int ret; | |
659 | unsigned long major, minor, temp; | |
660 | int i = 0; | |
661 | dev_t dev; | |
9355aede | 662 | u64 bps, iops; |
34d0f179 GJ |
663 | |
664 | memset(s, 0, sizeof(s)); | |
665 | ||
666 | while ((p = strsep(&buf, " ")) != NULL) { | |
667 | if (!*p) | |
668 | continue; | |
669 | ||
670 | s[i++] = p; | |
671 | ||
672 | /* Prevent from inputing too many things */ | |
673 | if (i == 3) | |
674 | break; | |
675 | } | |
676 | ||
677 | if (i != 2) | |
678 | return -EINVAL; | |
679 | ||
680 | p = strsep(&s[0], ":"); | |
681 | if (p != NULL) | |
682 | major_s = p; | |
683 | else | |
684 | return -EINVAL; | |
685 | ||
686 | minor_s = s[0]; | |
687 | if (!minor_s) | |
688 | return -EINVAL; | |
689 | ||
690 | ret = strict_strtoul(major_s, 10, &major); | |
691 | if (ret) | |
692 | return -EINVAL; | |
693 | ||
694 | ret = strict_strtoul(minor_s, 10, &minor); | |
695 | if (ret) | |
696 | return -EINVAL; | |
697 | ||
698 | dev = MKDEV(major, minor); | |
699 | ||
700 | ret = blkio_check_dev_num(dev); | |
701 | if (ret) | |
702 | return ret; | |
703 | ||
704 | newpn->dev = dev; | |
705 | ||
706 | if (s[1] == NULL) | |
707 | return -EINVAL; | |
708 | ||
062a644d VG |
709 | switch (plid) { |
710 | case BLKIO_POLICY_PROP: | |
711 | ret = strict_strtoul(s[1], 10, &temp); | |
712 | if (ret || (temp < BLKIO_WEIGHT_MIN && temp > 0) || | |
713 | temp > BLKIO_WEIGHT_MAX) | |
714 | return -EINVAL; | |
34d0f179 | 715 | |
062a644d VG |
716 | newpn->plid = plid; |
717 | newpn->fileid = fileid; | |
4c9eefa1 VG |
718 | newpn->val.weight = temp; |
719 | break; | |
720 | case BLKIO_POLICY_THROTL: | |
7702e8f4 VG |
721 | switch(fileid) { |
722 | case BLKIO_THROTL_read_bps_device: | |
723 | case BLKIO_THROTL_write_bps_device: | |
724 | ret = strict_strtoull(s[1], 10, &bps); | |
725 | if (ret) | |
726 | return -EINVAL; | |
4c9eefa1 | 727 | |
7702e8f4 VG |
728 | newpn->plid = plid; |
729 | newpn->fileid = fileid; | |
730 | newpn->val.bps = bps; | |
731 | break; | |
732 | case BLKIO_THROTL_read_iops_device: | |
733 | case BLKIO_THROTL_write_iops_device: | |
9355aede | 734 | ret = strict_strtoull(s[1], 10, &iops); |
7702e8f4 VG |
735 | if (ret) |
736 | return -EINVAL; | |
737 | ||
9355aede VG |
738 | if (iops > THROTL_IOPS_MAX) |
739 | return -EINVAL; | |
740 | ||
7702e8f4 VG |
741 | newpn->plid = plid; |
742 | newpn->fileid = fileid; | |
9355aede | 743 | newpn->val.iops = (unsigned int)iops; |
7702e8f4 VG |
744 | break; |
745 | } | |
062a644d VG |
746 | break; |
747 | default: | |
748 | BUG(); | |
749 | } | |
34d0f179 GJ |
750 | |
751 | return 0; | |
752 | } | |
753 | ||
754 | unsigned int blkcg_get_weight(struct blkio_cgroup *blkcg, | |
755 | dev_t dev) | |
756 | { | |
757 | struct blkio_policy_node *pn; | |
758 | ||
062a644d VG |
759 | pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_PROP, |
760 | BLKIO_PROP_weight_device); | |
34d0f179 | 761 | if (pn) |
4c9eefa1 | 762 | return pn->val.weight; |
34d0f179 GJ |
763 | else |
764 | return blkcg->weight; | |
765 | } | |
766 | EXPORT_SYMBOL_GPL(blkcg_get_weight); | |
767 | ||
4c9eefa1 VG |
768 | uint64_t blkcg_get_read_bps(struct blkio_cgroup *blkcg, dev_t dev) |
769 | { | |
770 | struct blkio_policy_node *pn; | |
771 | ||
772 | pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL, | |
773 | BLKIO_THROTL_read_bps_device); | |
774 | if (pn) | |
775 | return pn->val.bps; | |
776 | else | |
777 | return -1; | |
778 | } | |
779 | ||
780 | uint64_t blkcg_get_write_bps(struct blkio_cgroup *blkcg, dev_t dev) | |
781 | { | |
782 | struct blkio_policy_node *pn; | |
783 | pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL, | |
784 | BLKIO_THROTL_write_bps_device); | |
785 | if (pn) | |
786 | return pn->val.bps; | |
787 | else | |
788 | return -1; | |
789 | } | |
790 | ||
7702e8f4 VG |
791 | unsigned int blkcg_get_read_iops(struct blkio_cgroup *blkcg, dev_t dev) |
792 | { | |
793 | struct blkio_policy_node *pn; | |
794 | ||
795 | pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL, | |
796 | BLKIO_THROTL_read_iops_device); | |
797 | if (pn) | |
798 | return pn->val.iops; | |
799 | else | |
800 | return -1; | |
801 | } | |
802 | ||
803 | unsigned int blkcg_get_write_iops(struct blkio_cgroup *blkcg, dev_t dev) | |
804 | { | |
805 | struct blkio_policy_node *pn; | |
806 | pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL, | |
807 | BLKIO_THROTL_write_iops_device); | |
808 | if (pn) | |
809 | return pn->val.iops; | |
810 | else | |
811 | return -1; | |
812 | } | |
813 | ||
062a644d VG |
814 | /* Checks whether user asked for deleting a policy rule */ |
815 | static bool blkio_delete_rule_command(struct blkio_policy_node *pn) | |
816 | { | |
817 | switch(pn->plid) { | |
818 | case BLKIO_POLICY_PROP: | |
4c9eefa1 VG |
819 | if (pn->val.weight == 0) |
820 | return 1; | |
821 | break; | |
822 | case BLKIO_POLICY_THROTL: | |
7702e8f4 VG |
823 | switch(pn->fileid) { |
824 | case BLKIO_THROTL_read_bps_device: | |
825 | case BLKIO_THROTL_write_bps_device: | |
826 | if (pn->val.bps == 0) | |
827 | return 1; | |
828 | break; | |
829 | case BLKIO_THROTL_read_iops_device: | |
830 | case BLKIO_THROTL_write_iops_device: | |
831 | if (pn->val.iops == 0) | |
832 | return 1; | |
833 | } | |
062a644d VG |
834 | break; |
835 | default: | |
836 | BUG(); | |
837 | } | |
838 | ||
839 | return 0; | |
840 | } | |
841 | ||
842 | static void blkio_update_policy_rule(struct blkio_policy_node *oldpn, | |
843 | struct blkio_policy_node *newpn) | |
844 | { | |
845 | switch(oldpn->plid) { | |
846 | case BLKIO_POLICY_PROP: | |
4c9eefa1 VG |
847 | oldpn->val.weight = newpn->val.weight; |
848 | break; | |
849 | case BLKIO_POLICY_THROTL: | |
7702e8f4 VG |
850 | switch(newpn->fileid) { |
851 | case BLKIO_THROTL_read_bps_device: | |
852 | case BLKIO_THROTL_write_bps_device: | |
853 | oldpn->val.bps = newpn->val.bps; | |
854 | break; | |
855 | case BLKIO_THROTL_read_iops_device: | |
856 | case BLKIO_THROTL_write_iops_device: | |
857 | oldpn->val.iops = newpn->val.iops; | |
858 | } | |
062a644d VG |
859 | break; |
860 | default: | |
861 | BUG(); | |
862 | } | |
863 | } | |
864 | ||
865 | /* | |
866 | * Some rules/values in blkg have changed. Propogate those to respective | |
867 | * policies. | |
868 | */ | |
869 | static void blkio_update_blkg_policy(struct blkio_cgroup *blkcg, | |
870 | struct blkio_group *blkg, struct blkio_policy_node *pn) | |
871 | { | |
7702e8f4 | 872 | unsigned int weight, iops; |
4c9eefa1 | 873 | u64 bps; |
062a644d VG |
874 | |
875 | switch(pn->plid) { | |
876 | case BLKIO_POLICY_PROP: | |
4c9eefa1 | 877 | weight = pn->val.weight ? pn->val.weight : |
062a644d VG |
878 | blkcg->weight; |
879 | blkio_update_group_weight(blkg, weight); | |
880 | break; | |
4c9eefa1 VG |
881 | case BLKIO_POLICY_THROTL: |
882 | switch(pn->fileid) { | |
883 | case BLKIO_THROTL_read_bps_device: | |
884 | case BLKIO_THROTL_write_bps_device: | |
885 | bps = pn->val.bps ? pn->val.bps : (-1); | |
886 | blkio_update_group_bps(blkg, bps, pn->fileid); | |
887 | break; | |
7702e8f4 VG |
888 | case BLKIO_THROTL_read_iops_device: |
889 | case BLKIO_THROTL_write_iops_device: | |
890 | iops = pn->val.iops ? pn->val.iops : (-1); | |
891 | blkio_update_group_iops(blkg, iops, pn->fileid); | |
892 | break; | |
4c9eefa1 VG |
893 | } |
894 | break; | |
062a644d VG |
895 | default: |
896 | BUG(); | |
897 | } | |
898 | } | |
899 | ||
900 | /* | |
901 | * A policy node rule has been updated. Propogate this update to all the | |
902 | * block groups which might be affected by this update. | |
903 | */ | |
904 | static void blkio_update_policy_node_blkg(struct blkio_cgroup *blkcg, | |
905 | struct blkio_policy_node *pn) | |
906 | { | |
907 | struct blkio_group *blkg; | |
908 | struct hlist_node *n; | |
909 | ||
910 | spin_lock(&blkio_list_lock); | |
911 | spin_lock_irq(&blkcg->lock); | |
34d0f179 | 912 | |
062a644d VG |
913 | hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) { |
914 | if (pn->dev != blkg->dev || pn->plid != blkg->plid) | |
915 | continue; | |
916 | blkio_update_blkg_policy(blkcg, blkg, pn); | |
917 | } | |
918 | ||
919 | spin_unlock_irq(&blkcg->lock); | |
920 | spin_unlock(&blkio_list_lock); | |
921 | } | |
34d0f179 | 922 | |
062a644d VG |
923 | static int blkiocg_file_write(struct cgroup *cgrp, struct cftype *cft, |
924 | const char *buffer) | |
34d0f179 GJ |
925 | { |
926 | int ret = 0; | |
927 | char *buf; | |
928 | struct blkio_policy_node *newpn, *pn; | |
929 | struct blkio_cgroup *blkcg; | |
34d0f179 | 930 | int keep_newpn = 0; |
062a644d VG |
931 | enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); |
932 | int fileid = BLKIOFILE_ATTR(cft->private); | |
34d0f179 GJ |
933 | |
934 | buf = kstrdup(buffer, GFP_KERNEL); | |
935 | if (!buf) | |
936 | return -ENOMEM; | |
937 | ||
938 | newpn = kzalloc(sizeof(*newpn), GFP_KERNEL); | |
939 | if (!newpn) { | |
940 | ret = -ENOMEM; | |
941 | goto free_buf; | |
942 | } | |
943 | ||
062a644d | 944 | ret = blkio_policy_parse_and_set(buf, newpn, plid, fileid); |
34d0f179 GJ |
945 | if (ret) |
946 | goto free_newpn; | |
947 | ||
948 | blkcg = cgroup_to_blkio_cgroup(cgrp); | |
949 | ||
950 | spin_lock_irq(&blkcg->lock); | |
951 | ||
062a644d | 952 | pn = blkio_policy_search_node(blkcg, newpn->dev, plid, fileid); |
34d0f179 | 953 | if (!pn) { |
062a644d | 954 | if (!blkio_delete_rule_command(newpn)) { |
34d0f179 GJ |
955 | blkio_policy_insert_node(blkcg, newpn); |
956 | keep_newpn = 1; | |
957 | } | |
958 | spin_unlock_irq(&blkcg->lock); | |
959 | goto update_io_group; | |
960 | } | |
961 | ||
062a644d | 962 | if (blkio_delete_rule_command(newpn)) { |
34d0f179 GJ |
963 | blkio_policy_delete_node(pn); |
964 | spin_unlock_irq(&blkcg->lock); | |
965 | goto update_io_group; | |
966 | } | |
967 | spin_unlock_irq(&blkcg->lock); | |
968 | ||
062a644d | 969 | blkio_update_policy_rule(pn, newpn); |
34d0f179 GJ |
970 | |
971 | update_io_group: | |
062a644d | 972 | blkio_update_policy_node_blkg(blkcg, newpn); |
34d0f179 GJ |
973 | |
974 | free_newpn: | |
975 | if (!keep_newpn) | |
976 | kfree(newpn); | |
977 | free_buf: | |
978 | kfree(buf); | |
979 | return ret; | |
980 | } | |
981 | ||
062a644d VG |
982 | static void |
983 | blkio_print_policy_node(struct seq_file *m, struct blkio_policy_node *pn) | |
34d0f179 | 984 | { |
062a644d VG |
985 | switch(pn->plid) { |
986 | case BLKIO_POLICY_PROP: | |
987 | if (pn->fileid == BLKIO_PROP_weight_device) | |
988 | seq_printf(m, "%u:%u\t%u\n", MAJOR(pn->dev), | |
4c9eefa1 VG |
989 | MINOR(pn->dev), pn->val.weight); |
990 | break; | |
991 | case BLKIO_POLICY_THROTL: | |
7702e8f4 VG |
992 | switch(pn->fileid) { |
993 | case BLKIO_THROTL_read_bps_device: | |
994 | case BLKIO_THROTL_write_bps_device: | |
4c9eefa1 VG |
995 | seq_printf(m, "%u:%u\t%llu\n", MAJOR(pn->dev), |
996 | MINOR(pn->dev), pn->val.bps); | |
7702e8f4 VG |
997 | break; |
998 | case BLKIO_THROTL_read_iops_device: | |
999 | case BLKIO_THROTL_write_iops_device: | |
1000 | seq_printf(m, "%u:%u\t%u\n", MAJOR(pn->dev), | |
1001 | MINOR(pn->dev), pn->val.iops); | |
1002 | break; | |
1003 | } | |
062a644d VG |
1004 | break; |
1005 | default: | |
1006 | BUG(); | |
1007 | } | |
1008 | } | |
34d0f179 | 1009 | |
062a644d VG |
1010 | /* cgroup files which read their data from policy nodes end up here */ |
1011 | static void blkio_read_policy_node_files(struct cftype *cft, | |
1012 | struct blkio_cgroup *blkcg, struct seq_file *m) | |
34d0f179 | 1013 | { |
34d0f179 | 1014 | struct blkio_policy_node *pn; |
34d0f179 | 1015 | |
0f3942a3 JA |
1016 | if (!list_empty(&blkcg->policy_list)) { |
1017 | spin_lock_irq(&blkcg->lock); | |
1018 | list_for_each_entry(pn, &blkcg->policy_list, node) { | |
062a644d VG |
1019 | if (!pn_matches_cftype(cft, pn)) |
1020 | continue; | |
1021 | blkio_print_policy_node(m, pn); | |
0f3942a3 JA |
1022 | } |
1023 | spin_unlock_irq(&blkcg->lock); | |
34d0f179 | 1024 | } |
062a644d VG |
1025 | } |
1026 | ||
1027 | static int blkiocg_file_read(struct cgroup *cgrp, struct cftype *cft, | |
1028 | struct seq_file *m) | |
1029 | { | |
1030 | struct blkio_cgroup *blkcg; | |
1031 | enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); | |
1032 | int name = BLKIOFILE_ATTR(cft->private); | |
1033 | ||
1034 | blkcg = cgroup_to_blkio_cgroup(cgrp); | |
1035 | ||
1036 | switch(plid) { | |
1037 | case BLKIO_POLICY_PROP: | |
1038 | switch(name) { | |
1039 | case BLKIO_PROP_weight_device: | |
1040 | blkio_read_policy_node_files(cft, blkcg, m); | |
1041 | return 0; | |
1042 | default: | |
1043 | BUG(); | |
1044 | } | |
1045 | break; | |
4c9eefa1 VG |
1046 | case BLKIO_POLICY_THROTL: |
1047 | switch(name){ | |
1048 | case BLKIO_THROTL_read_bps_device: | |
1049 | case BLKIO_THROTL_write_bps_device: | |
7702e8f4 VG |
1050 | case BLKIO_THROTL_read_iops_device: |
1051 | case BLKIO_THROTL_write_iops_device: | |
4c9eefa1 VG |
1052 | blkio_read_policy_node_files(cft, blkcg, m); |
1053 | return 0; | |
1054 | default: | |
1055 | BUG(); | |
1056 | } | |
1057 | break; | |
062a644d VG |
1058 | default: |
1059 | BUG(); | |
1060 | } | |
1061 | ||
1062 | return 0; | |
1063 | } | |
1064 | ||
1065 | static int blkio_read_blkg_stats(struct blkio_cgroup *blkcg, | |
1066 | struct cftype *cft, struct cgroup_map_cb *cb, enum stat_type type, | |
1067 | bool show_total) | |
1068 | { | |
1069 | struct blkio_group *blkg; | |
1070 | struct hlist_node *n; | |
1071 | uint64_t cgroup_total = 0; | |
1072 | ||
1073 | rcu_read_lock(); | |
1074 | hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) { | |
1075 | if (blkg->dev) { | |
1076 | if (!cftype_blkg_same_policy(cft, blkg)) | |
1077 | continue; | |
1078 | spin_lock_irq(&blkg->stats_lock); | |
1079 | cgroup_total += blkio_get_stat(blkg, cb, blkg->dev, | |
1080 | type); | |
1081 | spin_unlock_irq(&blkg->stats_lock); | |
1082 | } | |
1083 | } | |
1084 | if (show_total) | |
1085 | cb->fill(cb, "Total", cgroup_total); | |
1086 | rcu_read_unlock(); | |
1087 | return 0; | |
1088 | } | |
1089 | ||
1090 | /* All map kind of cgroup file get serviced by this function */ | |
1091 | static int blkiocg_file_read_map(struct cgroup *cgrp, struct cftype *cft, | |
1092 | struct cgroup_map_cb *cb) | |
1093 | { | |
1094 | struct blkio_cgroup *blkcg; | |
1095 | enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); | |
1096 | int name = BLKIOFILE_ATTR(cft->private); | |
1097 | ||
1098 | blkcg = cgroup_to_blkio_cgroup(cgrp); | |
1099 | ||
1100 | switch(plid) { | |
1101 | case BLKIO_POLICY_PROP: | |
1102 | switch(name) { | |
1103 | case BLKIO_PROP_time: | |
1104 | return blkio_read_blkg_stats(blkcg, cft, cb, | |
1105 | BLKIO_STAT_TIME, 0); | |
1106 | case BLKIO_PROP_sectors: | |
1107 | return blkio_read_blkg_stats(blkcg, cft, cb, | |
1108 | BLKIO_STAT_SECTORS, 0); | |
1109 | case BLKIO_PROP_io_service_bytes: | |
1110 | return blkio_read_blkg_stats(blkcg, cft, cb, | |
1111 | BLKIO_STAT_SERVICE_BYTES, 1); | |
1112 | case BLKIO_PROP_io_serviced: | |
1113 | return blkio_read_blkg_stats(blkcg, cft, cb, | |
1114 | BLKIO_STAT_SERVICED, 1); | |
1115 | case BLKIO_PROP_io_service_time: | |
1116 | return blkio_read_blkg_stats(blkcg, cft, cb, | |
1117 | BLKIO_STAT_SERVICE_TIME, 1); | |
1118 | case BLKIO_PROP_io_wait_time: | |
1119 | return blkio_read_blkg_stats(blkcg, cft, cb, | |
1120 | BLKIO_STAT_WAIT_TIME, 1); | |
1121 | case BLKIO_PROP_io_merged: | |
1122 | return blkio_read_blkg_stats(blkcg, cft, cb, | |
1123 | BLKIO_STAT_MERGED, 1); | |
1124 | case BLKIO_PROP_io_queued: | |
1125 | return blkio_read_blkg_stats(blkcg, cft, cb, | |
1126 | BLKIO_STAT_QUEUED, 1); | |
1127 | #ifdef CONFIG_DEBUG_BLK_CGROUP | |
1128 | case BLKIO_PROP_dequeue: | |
1129 | return blkio_read_blkg_stats(blkcg, cft, cb, | |
1130 | BLKIO_STAT_DEQUEUE, 0); | |
1131 | case BLKIO_PROP_avg_queue_size: | |
1132 | return blkio_read_blkg_stats(blkcg, cft, cb, | |
1133 | BLKIO_STAT_AVG_QUEUE_SIZE, 0); | |
1134 | case BLKIO_PROP_group_wait_time: | |
1135 | return blkio_read_blkg_stats(blkcg, cft, cb, | |
1136 | BLKIO_STAT_GROUP_WAIT_TIME, 0); | |
1137 | case BLKIO_PROP_idle_time: | |
1138 | return blkio_read_blkg_stats(blkcg, cft, cb, | |
1139 | BLKIO_STAT_IDLE_TIME, 0); | |
1140 | case BLKIO_PROP_empty_time: | |
1141 | return blkio_read_blkg_stats(blkcg, cft, cb, | |
1142 | BLKIO_STAT_EMPTY_TIME, 0); | |
1143 | #endif | |
1144 | default: | |
1145 | BUG(); | |
1146 | } | |
1147 | break; | |
4c9eefa1 VG |
1148 | case BLKIO_POLICY_THROTL: |
1149 | switch(name){ | |
1150 | case BLKIO_THROTL_io_service_bytes: | |
1151 | return blkio_read_blkg_stats(blkcg, cft, cb, | |
1152 | BLKIO_STAT_SERVICE_BYTES, 1); | |
1153 | case BLKIO_THROTL_io_serviced: | |
1154 | return blkio_read_blkg_stats(blkcg, cft, cb, | |
1155 | BLKIO_STAT_SERVICED, 1); | |
1156 | default: | |
1157 | BUG(); | |
1158 | } | |
1159 | break; | |
062a644d VG |
1160 | default: |
1161 | BUG(); | |
1162 | } | |
1163 | ||
1164 | return 0; | |
1165 | } | |
1166 | ||
1167 | static int blkio_weight_write(struct blkio_cgroup *blkcg, u64 val) | |
1168 | { | |
1169 | struct blkio_group *blkg; | |
1170 | struct hlist_node *n; | |
1171 | struct blkio_policy_node *pn; | |
1172 | ||
1173 | if (val < BLKIO_WEIGHT_MIN || val > BLKIO_WEIGHT_MAX) | |
1174 | return -EINVAL; | |
1175 | ||
1176 | spin_lock(&blkio_list_lock); | |
1177 | spin_lock_irq(&blkcg->lock); | |
1178 | blkcg->weight = (unsigned int)val; | |
1179 | ||
1180 | hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) { | |
1181 | pn = blkio_policy_search_node(blkcg, blkg->dev, | |
1182 | BLKIO_POLICY_PROP, BLKIO_PROP_weight_device); | |
1183 | if (pn) | |
1184 | continue; | |
1185 | ||
1186 | blkio_update_group_weight(blkg, blkcg->weight); | |
1187 | } | |
1188 | spin_unlock_irq(&blkcg->lock); | |
1189 | spin_unlock(&blkio_list_lock); | |
1190 | return 0; | |
1191 | } | |
1192 | ||
1193 | static u64 blkiocg_file_read_u64 (struct cgroup *cgrp, struct cftype *cft) { | |
1194 | struct blkio_cgroup *blkcg; | |
1195 | enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); | |
1196 | int name = BLKIOFILE_ATTR(cft->private); | |
1197 | ||
1198 | blkcg = cgroup_to_blkio_cgroup(cgrp); | |
1199 | ||
1200 | switch(plid) { | |
1201 | case BLKIO_POLICY_PROP: | |
1202 | switch(name) { | |
1203 | case BLKIO_PROP_weight: | |
1204 | return (u64)blkcg->weight; | |
1205 | } | |
1206 | break; | |
1207 | default: | |
1208 | BUG(); | |
1209 | } | |
1210 | return 0; | |
1211 | } | |
1212 | ||
1213 | static int | |
1214 | blkiocg_file_write_u64(struct cgroup *cgrp, struct cftype *cft, u64 val) | |
1215 | { | |
1216 | struct blkio_cgroup *blkcg; | |
1217 | enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); | |
1218 | int name = BLKIOFILE_ATTR(cft->private); | |
1219 | ||
1220 | blkcg = cgroup_to_blkio_cgroup(cgrp); | |
1221 | ||
1222 | switch(plid) { | |
1223 | case BLKIO_POLICY_PROP: | |
1224 | switch(name) { | |
1225 | case BLKIO_PROP_weight: | |
1226 | return blkio_weight_write(blkcg, val); | |
1227 | } | |
1228 | break; | |
1229 | default: | |
1230 | BUG(); | |
1231 | } | |
34d0f179 | 1232 | |
34d0f179 GJ |
1233 | return 0; |
1234 | } | |
1235 | ||
31e4c28d | 1236 | struct cftype blkio_files[] = { |
34d0f179 GJ |
1237 | { |
1238 | .name = "weight_device", | |
062a644d VG |
1239 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1240 | BLKIO_PROP_weight_device), | |
1241 | .read_seq_string = blkiocg_file_read, | |
1242 | .write_string = blkiocg_file_write, | |
34d0f179 GJ |
1243 | .max_write_len = 256, |
1244 | }, | |
31e4c28d VG |
1245 | { |
1246 | .name = "weight", | |
062a644d VG |
1247 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1248 | BLKIO_PROP_weight), | |
1249 | .read_u64 = blkiocg_file_read_u64, | |
1250 | .write_u64 = blkiocg_file_write_u64, | |
31e4c28d | 1251 | }, |
22084190 VG |
1252 | { |
1253 | .name = "time", | |
062a644d VG |
1254 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1255 | BLKIO_PROP_time), | |
1256 | .read_map = blkiocg_file_read_map, | |
22084190 VG |
1257 | }, |
1258 | { | |
1259 | .name = "sectors", | |
062a644d VG |
1260 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1261 | BLKIO_PROP_sectors), | |
1262 | .read_map = blkiocg_file_read_map, | |
303a3acb DS |
1263 | }, |
1264 | { | |
1265 | .name = "io_service_bytes", | |
062a644d VG |
1266 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1267 | BLKIO_PROP_io_service_bytes), | |
1268 | .read_map = blkiocg_file_read_map, | |
303a3acb DS |
1269 | }, |
1270 | { | |
1271 | .name = "io_serviced", | |
062a644d VG |
1272 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1273 | BLKIO_PROP_io_serviced), | |
1274 | .read_map = blkiocg_file_read_map, | |
303a3acb DS |
1275 | }, |
1276 | { | |
1277 | .name = "io_service_time", | |
062a644d VG |
1278 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1279 | BLKIO_PROP_io_service_time), | |
1280 | .read_map = blkiocg_file_read_map, | |
303a3acb DS |
1281 | }, |
1282 | { | |
1283 | .name = "io_wait_time", | |
062a644d VG |
1284 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1285 | BLKIO_PROP_io_wait_time), | |
1286 | .read_map = blkiocg_file_read_map, | |
84c124da | 1287 | }, |
812d4026 DS |
1288 | { |
1289 | .name = "io_merged", | |
062a644d VG |
1290 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1291 | BLKIO_PROP_io_merged), | |
1292 | .read_map = blkiocg_file_read_map, | |
812d4026 | 1293 | }, |
cdc1184c DS |
1294 | { |
1295 | .name = "io_queued", | |
062a644d VG |
1296 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1297 | BLKIO_PROP_io_queued), | |
1298 | .read_map = blkiocg_file_read_map, | |
cdc1184c | 1299 | }, |
84c124da DS |
1300 | { |
1301 | .name = "reset_stats", | |
1302 | .write_u64 = blkiocg_reset_stats, | |
22084190 | 1303 | }, |
13f98250 VG |
1304 | #ifdef CONFIG_BLK_DEV_THROTTLING |
1305 | { | |
1306 | .name = "throttle.read_bps_device", | |
1307 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, | |
1308 | BLKIO_THROTL_read_bps_device), | |
1309 | .read_seq_string = blkiocg_file_read, | |
1310 | .write_string = blkiocg_file_write, | |
1311 | .max_write_len = 256, | |
1312 | }, | |
1313 | ||
1314 | { | |
1315 | .name = "throttle.write_bps_device", | |
1316 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, | |
1317 | BLKIO_THROTL_write_bps_device), | |
1318 | .read_seq_string = blkiocg_file_read, | |
1319 | .write_string = blkiocg_file_write, | |
1320 | .max_write_len = 256, | |
1321 | }, | |
1322 | ||
1323 | { | |
1324 | .name = "throttle.read_iops_device", | |
1325 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, | |
1326 | BLKIO_THROTL_read_iops_device), | |
1327 | .read_seq_string = blkiocg_file_read, | |
1328 | .write_string = blkiocg_file_write, | |
1329 | .max_write_len = 256, | |
1330 | }, | |
1331 | ||
1332 | { | |
1333 | .name = "throttle.write_iops_device", | |
1334 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, | |
1335 | BLKIO_THROTL_write_iops_device), | |
1336 | .read_seq_string = blkiocg_file_read, | |
1337 | .write_string = blkiocg_file_write, | |
1338 | .max_write_len = 256, | |
1339 | }, | |
1340 | { | |
1341 | .name = "throttle.io_service_bytes", | |
1342 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, | |
1343 | BLKIO_THROTL_io_service_bytes), | |
1344 | .read_map = blkiocg_file_read_map, | |
1345 | }, | |
1346 | { | |
1347 | .name = "throttle.io_serviced", | |
1348 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, | |
1349 | BLKIO_THROTL_io_serviced), | |
1350 | .read_map = blkiocg_file_read_map, | |
1351 | }, | |
1352 | #endif /* CONFIG_BLK_DEV_THROTTLING */ | |
1353 | ||
22084190 | 1354 | #ifdef CONFIG_DEBUG_BLK_CGROUP |
cdc1184c DS |
1355 | { |
1356 | .name = "avg_queue_size", | |
062a644d VG |
1357 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1358 | BLKIO_PROP_avg_queue_size), | |
1359 | .read_map = blkiocg_file_read_map, | |
cdc1184c | 1360 | }, |
812df48d DS |
1361 | { |
1362 | .name = "group_wait_time", | |
062a644d VG |
1363 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1364 | BLKIO_PROP_group_wait_time), | |
1365 | .read_map = blkiocg_file_read_map, | |
812df48d DS |
1366 | }, |
1367 | { | |
1368 | .name = "idle_time", | |
062a644d VG |
1369 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1370 | BLKIO_PROP_idle_time), | |
1371 | .read_map = blkiocg_file_read_map, | |
812df48d DS |
1372 | }, |
1373 | { | |
1374 | .name = "empty_time", | |
062a644d VG |
1375 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1376 | BLKIO_PROP_empty_time), | |
1377 | .read_map = blkiocg_file_read_map, | |
812df48d | 1378 | }, |
cdc1184c | 1379 | { |
22084190 | 1380 | .name = "dequeue", |
062a644d VG |
1381 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1382 | BLKIO_PROP_dequeue), | |
1383 | .read_map = blkiocg_file_read_map, | |
cdc1184c | 1384 | }, |
22084190 | 1385 | #endif |
31e4c28d VG |
1386 | }; |
1387 | ||
1388 | static int blkiocg_populate(struct cgroup_subsys *subsys, struct cgroup *cgroup) | |
1389 | { | |
1390 | return cgroup_add_files(cgroup, subsys, blkio_files, | |
1391 | ARRAY_SIZE(blkio_files)); | |
1392 | } | |
1393 | ||
1394 | static void blkiocg_destroy(struct cgroup_subsys *subsys, struct cgroup *cgroup) | |
1395 | { | |
1396 | struct blkio_cgroup *blkcg = cgroup_to_blkio_cgroup(cgroup); | |
b1c35769 VG |
1397 | unsigned long flags; |
1398 | struct blkio_group *blkg; | |
1399 | void *key; | |
3e252066 | 1400 | struct blkio_policy_type *blkiop; |
34d0f179 | 1401 | struct blkio_policy_node *pn, *pntmp; |
b1c35769 VG |
1402 | |
1403 | rcu_read_lock(); | |
0f3942a3 JA |
1404 | do { |
1405 | spin_lock_irqsave(&blkcg->lock, flags); | |
b1c35769 | 1406 | |
0f3942a3 JA |
1407 | if (hlist_empty(&blkcg->blkg_list)) { |
1408 | spin_unlock_irqrestore(&blkcg->lock, flags); | |
1409 | break; | |
1410 | } | |
b1c35769 | 1411 | |
0f3942a3 JA |
1412 | blkg = hlist_entry(blkcg->blkg_list.first, struct blkio_group, |
1413 | blkcg_node); | |
1414 | key = rcu_dereference(blkg->key); | |
1415 | __blkiocg_del_blkio_group(blkg); | |
31e4c28d | 1416 | |
0f3942a3 | 1417 | spin_unlock_irqrestore(&blkcg->lock, flags); |
b1c35769 | 1418 | |
0f3942a3 JA |
1419 | /* |
1420 | * This blkio_group is being unlinked as associated cgroup is | |
1421 | * going away. Let all the IO controlling policies know about | |
61014e96 | 1422 | * this event. |
0f3942a3 JA |
1423 | */ |
1424 | spin_lock(&blkio_list_lock); | |
61014e96 VG |
1425 | list_for_each_entry(blkiop, &blkio_list, list) { |
1426 | if (blkiop->plid != blkg->plid) | |
1427 | continue; | |
0f3942a3 | 1428 | blkiop->ops.blkio_unlink_group_fn(key, blkg); |
61014e96 | 1429 | } |
0f3942a3 JA |
1430 | spin_unlock(&blkio_list_lock); |
1431 | } while (1); | |
34d0f179 | 1432 | |
34d0f179 GJ |
1433 | list_for_each_entry_safe(pn, pntmp, &blkcg->policy_list, node) { |
1434 | blkio_policy_delete_node(pn); | |
1435 | kfree(pn); | |
1436 | } | |
0f3942a3 | 1437 | |
31e4c28d | 1438 | free_css_id(&blkio_subsys, &blkcg->css); |
b1c35769 | 1439 | rcu_read_unlock(); |
67523c48 BB |
1440 | if (blkcg != &blkio_root_cgroup) |
1441 | kfree(blkcg); | |
31e4c28d VG |
1442 | } |
1443 | ||
1444 | static struct cgroup_subsys_state * | |
1445 | blkiocg_create(struct cgroup_subsys *subsys, struct cgroup *cgroup) | |
1446 | { | |
0341509f LZ |
1447 | struct blkio_cgroup *blkcg; |
1448 | struct cgroup *parent = cgroup->parent; | |
31e4c28d | 1449 | |
0341509f | 1450 | if (!parent) { |
31e4c28d VG |
1451 | blkcg = &blkio_root_cgroup; |
1452 | goto done; | |
1453 | } | |
1454 | ||
1455 | /* Currently we do not support hierarchy deeper than two level (0,1) */ | |
0341509f | 1456 | if (parent != cgroup->top_cgroup) |
96aa1b41 | 1457 | return ERR_PTR(-EPERM); |
31e4c28d VG |
1458 | |
1459 | blkcg = kzalloc(sizeof(*blkcg), GFP_KERNEL); | |
1460 | if (!blkcg) | |
1461 | return ERR_PTR(-ENOMEM); | |
1462 | ||
1463 | blkcg->weight = BLKIO_WEIGHT_DEFAULT; | |
1464 | done: | |
1465 | spin_lock_init(&blkcg->lock); | |
1466 | INIT_HLIST_HEAD(&blkcg->blkg_list); | |
1467 | ||
34d0f179 | 1468 | INIT_LIST_HEAD(&blkcg->policy_list); |
31e4c28d VG |
1469 | return &blkcg->css; |
1470 | } | |
1471 | ||
1472 | /* | |
1473 | * We cannot support shared io contexts, as we have no mean to support | |
1474 | * two tasks with the same ioc in two different groups without major rework | |
1475 | * of the main cic data structures. For now we allow a task to change | |
1476 | * its cgroup only if it's the only owner of its ioc. | |
1477 | */ | |
1478 | static int blkiocg_can_attach(struct cgroup_subsys *subsys, | |
1479 | struct cgroup *cgroup, struct task_struct *tsk, | |
1480 | bool threadgroup) | |
1481 | { | |
1482 | struct io_context *ioc; | |
1483 | int ret = 0; | |
1484 | ||
1485 | /* task_lock() is needed to avoid races with exit_io_context() */ | |
1486 | task_lock(tsk); | |
1487 | ioc = tsk->io_context; | |
1488 | if (ioc && atomic_read(&ioc->nr_tasks) > 1) | |
1489 | ret = -EINVAL; | |
1490 | task_unlock(tsk); | |
1491 | ||
1492 | return ret; | |
1493 | } | |
1494 | ||
1495 | static void blkiocg_attach(struct cgroup_subsys *subsys, struct cgroup *cgroup, | |
1496 | struct cgroup *prev, struct task_struct *tsk, | |
1497 | bool threadgroup) | |
1498 | { | |
1499 | struct io_context *ioc; | |
1500 | ||
1501 | task_lock(tsk); | |
1502 | ioc = tsk->io_context; | |
1503 | if (ioc) | |
1504 | ioc->cgroup_changed = 1; | |
1505 | task_unlock(tsk); | |
1506 | } | |
1507 | ||
3e252066 VG |
1508 | void blkio_policy_register(struct blkio_policy_type *blkiop) |
1509 | { | |
1510 | spin_lock(&blkio_list_lock); | |
1511 | list_add_tail(&blkiop->list, &blkio_list); | |
1512 | spin_unlock(&blkio_list_lock); | |
1513 | } | |
1514 | EXPORT_SYMBOL_GPL(blkio_policy_register); | |
1515 | ||
1516 | void blkio_policy_unregister(struct blkio_policy_type *blkiop) | |
1517 | { | |
1518 | spin_lock(&blkio_list_lock); | |
1519 | list_del_init(&blkiop->list); | |
1520 | spin_unlock(&blkio_list_lock); | |
1521 | } | |
1522 | EXPORT_SYMBOL_GPL(blkio_policy_unregister); | |
67523c48 BB |
1523 | |
1524 | static int __init init_cgroup_blkio(void) | |
1525 | { | |
1526 | return cgroup_load_subsys(&blkio_subsys); | |
1527 | } | |
1528 | ||
1529 | static void __exit exit_cgroup_blkio(void) | |
1530 | { | |
1531 | cgroup_unload_subsys(&blkio_subsys); | |
1532 | } | |
1533 | ||
1534 | module_init(init_cgroup_blkio); | |
1535 | module_exit(exit_cgroup_blkio); | |
1536 | MODULE_LICENSE("GPL"); |