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Source at commit b386be689295730688885552666ea40b2e639b14 created 11 years 11 months ago. By Maarten ter Huurne, Revert "MIPS: JZ4740: reset: Initialize hibernate wakeup counters." | |
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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> |
14 | #include <linux/seq_file.h> |
15 | #include <linux/kdev_t.h> |
16 | #include <linux/module.h> |
17 | #include <linux/err.h> |
18 | #include <linux/blkdev.h> |
19 | #include <linux/slab.h> |
20 | #include "blk-cgroup.h" |
21 | #include <linux/genhd.h> |
22 | |
23 | #define MAX_KEY_LEN 100 |
24 | |
25 | static DEFINE_SPINLOCK(blkio_list_lock); |
26 | static LIST_HEAD(blkio_list); |
27 | |
28 | struct blkio_cgroup blkio_root_cgroup = { .weight = 2*BLKIO_WEIGHT_DEFAULT }; |
29 | EXPORT_SYMBOL_GPL(blkio_root_cgroup); |
30 | |
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 cgroup_taskset *); |
35 | static void blkiocg_attach(struct cgroup_subsys *, struct cgroup *, |
36 | struct cgroup_taskset *); |
37 | static void blkiocg_destroy(struct cgroup_subsys *, struct cgroup *); |
38 | static int blkiocg_populate(struct cgroup_subsys *, struct cgroup *); |
39 | |
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 | |
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 | |
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 | |
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 | |
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 * |
97 | blkio_policy_search_node(const struct blkio_cgroup *blkcg, dev_t dev, |
98 | enum blkio_policy_id plid, int fileid) |
99 | { |
100 | struct blkio_policy_node *pn; |
101 | |
102 | list_for_each_entry(pn, &blkcg->policy_list, node) { |
103 | if (pn->dev == dev && pn->plid == plid && pn->fileid == fileid) |
104 | return pn; |
105 | } |
106 | |
107 | return NULL; |
108 | } |
109 | |
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 | } |
115 | EXPORT_SYMBOL_GPL(cgroup_to_blkio_cgroup); |
116 | |
117 | struct blkio_cgroup *task_blkio_cgroup(struct task_struct *tsk) |
118 | { |
119 | return container_of(task_subsys_state(tsk, blkio_subsys_id), |
120 | struct blkio_cgroup, css); |
121 | } |
122 | EXPORT_SYMBOL_GPL(task_blkio_cgroup); |
123 | |
124 | static inline void |
125 | blkio_update_group_weight(struct blkio_group *blkg, unsigned int weight) |
126 | { |
127 | struct blkio_policy_type *blkiop; |
128 | |
129 | list_for_each_entry(blkiop, &blkio_list, list) { |
130 | /* If this policy does not own the blkg, do not send updates */ |
131 | if (blkiop->plid != blkg->plid) |
132 | continue; |
133 | if (blkiop->ops.blkio_update_group_weight_fn) |
134 | blkiop->ops.blkio_update_group_weight_fn(blkg->key, |
135 | blkg, weight); |
136 | } |
137 | } |
138 | |
139 | static inline void blkio_update_group_bps(struct blkio_group *blkg, u64 bps, |
140 | int fileid) |
141 | { |
142 | struct blkio_policy_type *blkiop; |
143 | |
144 | list_for_each_entry(blkiop, &blkio_list, list) { |
145 | |
146 | /* If this policy does not own the blkg, do not send updates */ |
147 | if (blkiop->plid != blkg->plid) |
148 | continue; |
149 | |
150 | if (fileid == BLKIO_THROTL_read_bps_device |
151 | && blkiop->ops.blkio_update_group_read_bps_fn) |
152 | blkiop->ops.blkio_update_group_read_bps_fn(blkg->key, |
153 | blkg, bps); |
154 | |
155 | if (fileid == BLKIO_THROTL_write_bps_device |
156 | && blkiop->ops.blkio_update_group_write_bps_fn) |
157 | blkiop->ops.blkio_update_group_write_bps_fn(blkg->key, |
158 | blkg, bps); |
159 | } |
160 | } |
161 | |
162 | static inline void blkio_update_group_iops(struct blkio_group *blkg, |
163 | unsigned int iops, int fileid) |
164 | { |
165 | struct blkio_policy_type *blkiop; |
166 | |
167 | list_for_each_entry(blkiop, &blkio_list, list) { |
168 | |
169 | /* If this policy does not own the blkg, do not send updates */ |
170 | if (blkiop->plid != blkg->plid) |
171 | continue; |
172 | |
173 | if (fileid == BLKIO_THROTL_read_iops_device |
174 | && blkiop->ops.blkio_update_group_read_iops_fn) |
175 | blkiop->ops.blkio_update_group_read_iops_fn(blkg->key, |
176 | blkg, iops); |
177 | |
178 | if (fileid == BLKIO_THROTL_write_iops_device |
179 | && blkiop->ops.blkio_update_group_write_iops_fn) |
180 | blkiop->ops.blkio_update_group_write_iops_fn(blkg->key, |
181 | blkg,iops); |
182 | } |
183 | } |
184 | |
185 | /* |
186 | * Add to the appropriate stat variable depending on the request type. |
187 | * This should be called with the blkg->stats_lock held. |
188 | */ |
189 | static void blkio_add_stat(uint64_t *stat, uint64_t add, bool direction, |
190 | bool sync) |
191 | { |
192 | if (direction) |
193 | stat[BLKIO_STAT_WRITE] += add; |
194 | else |
195 | stat[BLKIO_STAT_READ] += add; |
196 | if (sync) |
197 | stat[BLKIO_STAT_SYNC] += add; |
198 | else |
199 | stat[BLKIO_STAT_ASYNC] += add; |
200 | } |
201 | |
202 | /* |
203 | * Decrements the appropriate stat variable if non-zero depending on the |
204 | * request type. Panics on value being zero. |
205 | * This should be called with the blkg->stats_lock held. |
206 | */ |
207 | static void blkio_check_and_dec_stat(uint64_t *stat, bool direction, bool sync) |
208 | { |
209 | if (direction) { |
210 | BUG_ON(stat[BLKIO_STAT_WRITE] == 0); |
211 | stat[BLKIO_STAT_WRITE]--; |
212 | } else { |
213 | BUG_ON(stat[BLKIO_STAT_READ] == 0); |
214 | stat[BLKIO_STAT_READ]--; |
215 | } |
216 | if (sync) { |
217 | BUG_ON(stat[BLKIO_STAT_SYNC] == 0); |
218 | stat[BLKIO_STAT_SYNC]--; |
219 | } else { |
220 | BUG_ON(stat[BLKIO_STAT_ASYNC] == 0); |
221 | stat[BLKIO_STAT_ASYNC]--; |
222 | } |
223 | } |
224 | |
225 | #ifdef CONFIG_DEBUG_BLK_CGROUP |
226 | /* This should be called with the blkg->stats_lock held. */ |
227 | static void blkio_set_start_group_wait_time(struct blkio_group *blkg, |
228 | struct blkio_group *curr_blkg) |
229 | { |
230 | if (blkio_blkg_waiting(&blkg->stats)) |
231 | return; |
232 | if (blkg == curr_blkg) |
233 | return; |
234 | blkg->stats.start_group_wait_time = sched_clock(); |
235 | blkio_mark_blkg_waiting(&blkg->stats); |
236 | } |
237 | |
238 | /* This should be called with the blkg->stats_lock held. */ |
239 | static void blkio_update_group_wait_time(struct blkio_group_stats *stats) |
240 | { |
241 | unsigned long long now; |
242 | |
243 | if (!blkio_blkg_waiting(stats)) |
244 | return; |
245 | |
246 | now = sched_clock(); |
247 | if (time_after64(now, stats->start_group_wait_time)) |
248 | stats->group_wait_time += now - stats->start_group_wait_time; |
249 | blkio_clear_blkg_waiting(stats); |
250 | } |
251 | |
252 | /* This should be called with the blkg->stats_lock held. */ |
253 | static void blkio_end_empty_time(struct blkio_group_stats *stats) |
254 | { |
255 | unsigned long long now; |
256 | |
257 | if (!blkio_blkg_empty(stats)) |
258 | return; |
259 | |
260 | now = sched_clock(); |
261 | if (time_after64(now, stats->start_empty_time)) |
262 | stats->empty_time += now - stats->start_empty_time; |
263 | blkio_clear_blkg_empty(stats); |
264 | } |
265 | |
266 | void blkiocg_update_set_idle_time_stats(struct blkio_group *blkg) |
267 | { |
268 | unsigned long flags; |
269 | |
270 | spin_lock_irqsave(&blkg->stats_lock, flags); |
271 | BUG_ON(blkio_blkg_idling(&blkg->stats)); |
272 | blkg->stats.start_idle_time = sched_clock(); |
273 | blkio_mark_blkg_idling(&blkg->stats); |
274 | spin_unlock_irqrestore(&blkg->stats_lock, flags); |
275 | } |
276 | EXPORT_SYMBOL_GPL(blkiocg_update_set_idle_time_stats); |
277 | |
278 | void blkiocg_update_idle_time_stats(struct blkio_group *blkg) |
279 | { |
280 | unsigned long flags; |
281 | unsigned long long now; |
282 | struct blkio_group_stats *stats; |
283 | |
284 | spin_lock_irqsave(&blkg->stats_lock, flags); |
285 | stats = &blkg->stats; |
286 | if (blkio_blkg_idling(stats)) { |
287 | now = sched_clock(); |
288 | if (time_after64(now, stats->start_idle_time)) |
289 | stats->idle_time += now - stats->start_idle_time; |
290 | blkio_clear_blkg_idling(stats); |
291 | } |
292 | spin_unlock_irqrestore(&blkg->stats_lock, flags); |
293 | } |
294 | EXPORT_SYMBOL_GPL(blkiocg_update_idle_time_stats); |
295 | |
296 | void blkiocg_update_avg_queue_size_stats(struct blkio_group *blkg) |
297 | { |
298 | unsigned long flags; |
299 | struct blkio_group_stats *stats; |
300 | |
301 | spin_lock_irqsave(&blkg->stats_lock, flags); |
302 | stats = &blkg->stats; |
303 | stats->avg_queue_size_sum += |
304 | stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_READ] + |
305 | stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_WRITE]; |
306 | stats->avg_queue_size_samples++; |
307 | blkio_update_group_wait_time(stats); |
308 | spin_unlock_irqrestore(&blkg->stats_lock, flags); |
309 | } |
310 | EXPORT_SYMBOL_GPL(blkiocg_update_avg_queue_size_stats); |
311 | |
312 | void blkiocg_set_start_empty_time(struct blkio_group *blkg) |
313 | { |
314 | unsigned long flags; |
315 | struct blkio_group_stats *stats; |
316 | |
317 | spin_lock_irqsave(&blkg->stats_lock, flags); |
318 | stats = &blkg->stats; |
319 | |
320 | if (stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_READ] || |
321 | stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_WRITE]) { |
322 | spin_unlock_irqrestore(&blkg->stats_lock, flags); |
323 | return; |
324 | } |
325 | |
326 | /* |
327 | * group is already marked empty. This can happen if cfqq got new |
328 | * request in parent group and moved to this group while being added |
329 | * to service tree. Just ignore the event and move on. |
330 | */ |
331 | if(blkio_blkg_empty(stats)) { |
332 | spin_unlock_irqrestore(&blkg->stats_lock, flags); |
333 | return; |
334 | } |
335 | |
336 | stats->start_empty_time = sched_clock(); |
337 | blkio_mark_blkg_empty(stats); |
338 | spin_unlock_irqrestore(&blkg->stats_lock, flags); |
339 | } |
340 | EXPORT_SYMBOL_GPL(blkiocg_set_start_empty_time); |
341 | |
342 | void blkiocg_update_dequeue_stats(struct blkio_group *blkg, |
343 | unsigned long dequeue) |
344 | { |
345 | blkg->stats.dequeue += dequeue; |
346 | } |
347 | EXPORT_SYMBOL_GPL(blkiocg_update_dequeue_stats); |
348 | #else |
349 | static inline void blkio_set_start_group_wait_time(struct blkio_group *blkg, |
350 | struct blkio_group *curr_blkg) {} |
351 | static inline void blkio_end_empty_time(struct blkio_group_stats *stats) {} |
352 | #endif |
353 | |
354 | void blkiocg_update_io_add_stats(struct blkio_group *blkg, |
355 | struct blkio_group *curr_blkg, bool direction, |
356 | bool sync) |
357 | { |
358 | unsigned long flags; |
359 | |
360 | spin_lock_irqsave(&blkg->stats_lock, flags); |
361 | blkio_add_stat(blkg->stats.stat_arr[BLKIO_STAT_QUEUED], 1, direction, |
362 | sync); |
363 | blkio_end_empty_time(&blkg->stats); |
364 | blkio_set_start_group_wait_time(blkg, curr_blkg); |
365 | spin_unlock_irqrestore(&blkg->stats_lock, flags); |
366 | } |
367 | EXPORT_SYMBOL_GPL(blkiocg_update_io_add_stats); |
368 | |
369 | void blkiocg_update_io_remove_stats(struct blkio_group *blkg, |
370 | bool direction, bool sync) |
371 | { |
372 | unsigned long flags; |
373 | |
374 | spin_lock_irqsave(&blkg->stats_lock, flags); |
375 | blkio_check_and_dec_stat(blkg->stats.stat_arr[BLKIO_STAT_QUEUED], |
376 | direction, sync); |
377 | spin_unlock_irqrestore(&blkg->stats_lock, flags); |
378 | } |
379 | EXPORT_SYMBOL_GPL(blkiocg_update_io_remove_stats); |
380 | |
381 | void blkiocg_update_timeslice_used(struct blkio_group *blkg, unsigned long time, |
382 | unsigned long unaccounted_time) |
383 | { |
384 | unsigned long flags; |
385 | |
386 | spin_lock_irqsave(&blkg->stats_lock, flags); |
387 | blkg->stats.time += time; |
388 | #ifdef CONFIG_DEBUG_BLK_CGROUP |
389 | blkg->stats.unaccounted_time += unaccounted_time; |
390 | #endif |
391 | spin_unlock_irqrestore(&blkg->stats_lock, flags); |
392 | } |
393 | EXPORT_SYMBOL_GPL(blkiocg_update_timeslice_used); |
394 | |
395 | /* |
396 | * should be called under rcu read lock or queue lock to make sure blkg pointer |
397 | * is valid. |
398 | */ |
399 | void blkiocg_update_dispatch_stats(struct blkio_group *blkg, |
400 | uint64_t bytes, bool direction, bool sync) |
401 | { |
402 | struct blkio_group_stats_cpu *stats_cpu; |
403 | unsigned long flags; |
404 | |
405 | /* |
406 | * Disabling interrupts to provide mutual exclusion between two |
407 | * writes on same cpu. It probably is not needed for 64bit. Not |
408 | * optimizing that case yet. |
409 | */ |
410 | local_irq_save(flags); |
411 | |
412 | stats_cpu = this_cpu_ptr(blkg->stats_cpu); |
413 | |
414 | u64_stats_update_begin(&stats_cpu->syncp); |
415 | stats_cpu->sectors += bytes >> 9; |
416 | blkio_add_stat(stats_cpu->stat_arr_cpu[BLKIO_STAT_CPU_SERVICED], |
417 | 1, direction, sync); |
418 | blkio_add_stat(stats_cpu->stat_arr_cpu[BLKIO_STAT_CPU_SERVICE_BYTES], |
419 | bytes, direction, sync); |
420 | u64_stats_update_end(&stats_cpu->syncp); |
421 | local_irq_restore(flags); |
422 | } |
423 | EXPORT_SYMBOL_GPL(blkiocg_update_dispatch_stats); |
424 | |
425 | void blkiocg_update_completion_stats(struct blkio_group *blkg, |
426 | uint64_t start_time, uint64_t io_start_time, bool direction, bool sync) |
427 | { |
428 | struct blkio_group_stats *stats; |
429 | unsigned long flags; |
430 | unsigned long long now = sched_clock(); |
431 | |
432 | spin_lock_irqsave(&blkg->stats_lock, flags); |
433 | stats = &blkg->stats; |
434 | if (time_after64(now, io_start_time)) |
435 | blkio_add_stat(stats->stat_arr[BLKIO_STAT_SERVICE_TIME], |
436 | now - io_start_time, direction, sync); |
437 | if (time_after64(io_start_time, start_time)) |
438 | blkio_add_stat(stats->stat_arr[BLKIO_STAT_WAIT_TIME], |
439 | io_start_time - start_time, direction, sync); |
440 | spin_unlock_irqrestore(&blkg->stats_lock, flags); |
441 | } |
442 | EXPORT_SYMBOL_GPL(blkiocg_update_completion_stats); |
443 | |
444 | /* Merged stats are per cpu. */ |
445 | void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction, |
446 | bool sync) |
447 | { |
448 | struct blkio_group_stats_cpu *stats_cpu; |
449 | unsigned long flags; |
450 | |
451 | /* |
452 | * Disabling interrupts to provide mutual exclusion between two |
453 | * writes on same cpu. It probably is not needed for 64bit. Not |
454 | * optimizing that case yet. |
455 | */ |
456 | local_irq_save(flags); |
457 | |
458 | stats_cpu = this_cpu_ptr(blkg->stats_cpu); |
459 | |
460 | u64_stats_update_begin(&stats_cpu->syncp); |
461 | blkio_add_stat(stats_cpu->stat_arr_cpu[BLKIO_STAT_CPU_MERGED], 1, |
462 | direction, sync); |
463 | u64_stats_update_end(&stats_cpu->syncp); |
464 | local_irq_restore(flags); |
465 | } |
466 | EXPORT_SYMBOL_GPL(blkiocg_update_io_merged_stats); |
467 | |
468 | /* |
469 | * This function allocates the per cpu stats for blkio_group. Should be called |
470 | * from sleepable context as alloc_per_cpu() requires that. |
471 | */ |
472 | int blkio_alloc_blkg_stats(struct blkio_group *blkg) |
473 | { |
474 | /* Allocate memory for per cpu stats */ |
475 | blkg->stats_cpu = alloc_percpu(struct blkio_group_stats_cpu); |
476 | if (!blkg->stats_cpu) |
477 | return -ENOMEM; |
478 | return 0; |
479 | } |
480 | EXPORT_SYMBOL_GPL(blkio_alloc_blkg_stats); |
481 | |
482 | void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg, |
483 | struct blkio_group *blkg, void *key, dev_t dev, |
484 | enum blkio_policy_id plid) |
485 | { |
486 | unsigned long flags; |
487 | |
488 | spin_lock_irqsave(&blkcg->lock, flags); |
489 | spin_lock_init(&blkg->stats_lock); |
490 | rcu_assign_pointer(blkg->key, key); |
491 | blkg->blkcg_id = css_id(&blkcg->css); |
492 | hlist_add_head_rcu(&blkg->blkcg_node, &blkcg->blkg_list); |
493 | blkg->plid = plid; |
494 | spin_unlock_irqrestore(&blkcg->lock, flags); |
495 | /* Need to take css reference ? */ |
496 | cgroup_path(blkcg->css.cgroup, blkg->path, sizeof(blkg->path)); |
497 | blkg->dev = dev; |
498 | } |
499 | EXPORT_SYMBOL_GPL(blkiocg_add_blkio_group); |
500 | |
501 | static void __blkiocg_del_blkio_group(struct blkio_group *blkg) |
502 | { |
503 | hlist_del_init_rcu(&blkg->blkcg_node); |
504 | blkg->blkcg_id = 0; |
505 | } |
506 | |
507 | /* |
508 | * returns 0 if blkio_group was still on cgroup list. Otherwise returns 1 |
509 | * indicating that blk_group was unhashed by the time we got to it. |
510 | */ |
511 | int blkiocg_del_blkio_group(struct blkio_group *blkg) |
512 | { |
513 | struct blkio_cgroup *blkcg; |
514 | unsigned long flags; |
515 | struct cgroup_subsys_state *css; |
516 | int ret = 1; |
517 | |
518 | rcu_read_lock(); |
519 | css = css_lookup(&blkio_subsys, blkg->blkcg_id); |
520 | if (css) { |
521 | blkcg = container_of(css, struct blkio_cgroup, css); |
522 | spin_lock_irqsave(&blkcg->lock, flags); |
523 | if (!hlist_unhashed(&blkg->blkcg_node)) { |
524 | __blkiocg_del_blkio_group(blkg); |
525 | ret = 0; |
526 | } |
527 | spin_unlock_irqrestore(&blkcg->lock, flags); |
528 | } |
529 | |
530 | rcu_read_unlock(); |
531 | return ret; |
532 | } |
533 | EXPORT_SYMBOL_GPL(blkiocg_del_blkio_group); |
534 | |
535 | /* called under rcu_read_lock(). */ |
536 | struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg, void *key) |
537 | { |
538 | struct blkio_group *blkg; |
539 | struct hlist_node *n; |
540 | void *__key; |
541 | |
542 | hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) { |
543 | __key = blkg->key; |
544 | if (__key == key) |
545 | return blkg; |
546 | } |
547 | |
548 | return NULL; |
549 | } |
550 | EXPORT_SYMBOL_GPL(blkiocg_lookup_group); |
551 | |
552 | static void blkio_reset_stats_cpu(struct blkio_group *blkg) |
553 | { |
554 | struct blkio_group_stats_cpu *stats_cpu; |
555 | int i, j, k; |
556 | /* |
557 | * Note: On 64 bit arch this should not be an issue. This has the |
558 | * possibility of returning some inconsistent value on 32bit arch |
559 | * as 64bit update on 32bit is non atomic. Taking care of this |
560 | * corner case makes code very complicated, like sending IPIs to |
561 | * cpus, taking care of stats of offline cpus etc. |
562 | * |
563 | * reset stats is anyway more of a debug feature and this sounds a |
564 | * corner case. So I am not complicating the code yet until and |
565 | * unless this becomes a real issue. |
566 | */ |
567 | for_each_possible_cpu(i) { |
568 | stats_cpu = per_cpu_ptr(blkg->stats_cpu, i); |
569 | stats_cpu->sectors = 0; |
570 | for(j = 0; j < BLKIO_STAT_CPU_NR; j++) |
571 | for (k = 0; k < BLKIO_STAT_TOTAL; k++) |
572 | stats_cpu->stat_arr_cpu[j][k] = 0; |
573 | } |
574 | } |
575 | |
576 | static int |
577 | blkiocg_reset_stats(struct cgroup *cgroup, struct cftype *cftype, u64 val) |
578 | { |
579 | struct blkio_cgroup *blkcg; |
580 | struct blkio_group *blkg; |
581 | struct blkio_group_stats *stats; |
582 | struct hlist_node *n; |
583 | uint64_t queued[BLKIO_STAT_TOTAL]; |
584 | int i; |
585 | #ifdef CONFIG_DEBUG_BLK_CGROUP |
586 | bool idling, waiting, empty; |
587 | unsigned long long now = sched_clock(); |
588 | #endif |
589 | |
590 | blkcg = cgroup_to_blkio_cgroup(cgroup); |
591 | spin_lock_irq(&blkcg->lock); |
592 | hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) { |
593 | spin_lock(&blkg->stats_lock); |
594 | stats = &blkg->stats; |
595 | #ifdef CONFIG_DEBUG_BLK_CGROUP |
596 | idling = blkio_blkg_idling(stats); |
597 | waiting = blkio_blkg_waiting(stats); |
598 | empty = blkio_blkg_empty(stats); |
599 | #endif |
600 | for (i = 0; i < BLKIO_STAT_TOTAL; i++) |
601 | queued[i] = stats->stat_arr[BLKIO_STAT_QUEUED][i]; |
602 | memset(stats, 0, sizeof(struct blkio_group_stats)); |
603 | for (i = 0; i < BLKIO_STAT_TOTAL; i++) |
604 | stats->stat_arr[BLKIO_STAT_QUEUED][i] = queued[i]; |
605 | #ifdef CONFIG_DEBUG_BLK_CGROUP |
606 | if (idling) { |
607 | blkio_mark_blkg_idling(stats); |
608 | stats->start_idle_time = now; |
609 | } |
610 | if (waiting) { |
611 | blkio_mark_blkg_waiting(stats); |
612 | stats->start_group_wait_time = now; |
613 | } |
614 | if (empty) { |
615 | blkio_mark_blkg_empty(stats); |
616 | stats->start_empty_time = now; |
617 | } |
618 | #endif |
619 | spin_unlock(&blkg->stats_lock); |
620 | |
621 | /* Reset Per cpu stats which don't take blkg->stats_lock */ |
622 | blkio_reset_stats_cpu(blkg); |
623 | } |
624 | |
625 | spin_unlock_irq(&blkcg->lock); |
626 | return 0; |
627 | } |
628 | |
629 | static void blkio_get_key_name(enum stat_sub_type type, dev_t dev, char *str, |
630 | int chars_left, bool diskname_only) |
631 | { |
632 | snprintf(str, chars_left, "%d:%d", MAJOR(dev), MINOR(dev)); |
633 | chars_left -= strlen(str); |
634 | if (chars_left <= 0) { |
635 | printk(KERN_WARNING |
636 | "Possibly incorrect cgroup stat display format"); |
637 | return; |
638 | } |
639 | if (diskname_only) |
640 | return; |
641 | switch (type) { |
642 | case BLKIO_STAT_READ: |
643 | strlcat(str, " Read", chars_left); |
644 | break; |
645 | case BLKIO_STAT_WRITE: |
646 | strlcat(str, " Write", chars_left); |
647 | break; |
648 | case BLKIO_STAT_SYNC: |
649 | strlcat(str, " Sync", chars_left); |
650 | break; |
651 | case BLKIO_STAT_ASYNC: |
652 | strlcat(str, " Async", chars_left); |
653 | break; |
654 | case BLKIO_STAT_TOTAL: |
655 | strlcat(str, " Total", chars_left); |
656 | break; |
657 | default: |
658 | strlcat(str, " Invalid", chars_left); |
659 | } |
660 | } |
661 | |
662 | static uint64_t blkio_fill_stat(char *str, int chars_left, uint64_t val, |
663 | struct cgroup_map_cb *cb, dev_t dev) |
664 | { |
665 | blkio_get_key_name(0, dev, str, chars_left, true); |
666 | cb->fill(cb, str, val); |
667 | return val; |
668 | } |
669 | |
670 | |
671 | static uint64_t blkio_read_stat_cpu(struct blkio_group *blkg, |
672 | enum stat_type_cpu type, enum stat_sub_type sub_type) |
673 | { |
674 | int cpu; |
675 | struct blkio_group_stats_cpu *stats_cpu; |
676 | u64 val = 0, tval; |
677 | |
678 | for_each_possible_cpu(cpu) { |
679 | unsigned int start; |
680 | stats_cpu = per_cpu_ptr(blkg->stats_cpu, cpu); |
681 | |
682 | do { |
683 | start = u64_stats_fetch_begin(&stats_cpu->syncp); |
684 | if (type == BLKIO_STAT_CPU_SECTORS) |
685 | tval = stats_cpu->sectors; |
686 | else |
687 | tval = stats_cpu->stat_arr_cpu[type][sub_type]; |
688 | } while(u64_stats_fetch_retry(&stats_cpu->syncp, start)); |
689 | |
690 | val += tval; |
691 | } |
692 | |
693 | return val; |
694 | } |
695 | |
696 | static uint64_t blkio_get_stat_cpu(struct blkio_group *blkg, |
697 | struct cgroup_map_cb *cb, dev_t dev, enum stat_type_cpu type) |
698 | { |
699 | uint64_t disk_total, val; |
700 | char key_str[MAX_KEY_LEN]; |
701 | enum stat_sub_type sub_type; |
702 | |
703 | if (type == BLKIO_STAT_CPU_SECTORS) { |
704 | val = blkio_read_stat_cpu(blkg, type, 0); |
705 | return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, val, cb, dev); |
706 | } |
707 | |
708 | for (sub_type = BLKIO_STAT_READ; sub_type < BLKIO_STAT_TOTAL; |
709 | sub_type++) { |
710 | blkio_get_key_name(sub_type, dev, key_str, MAX_KEY_LEN, false); |
711 | val = blkio_read_stat_cpu(blkg, type, sub_type); |
712 | cb->fill(cb, key_str, val); |
713 | } |
714 | |
715 | disk_total = blkio_read_stat_cpu(blkg, type, BLKIO_STAT_READ) + |
716 | blkio_read_stat_cpu(blkg, type, BLKIO_STAT_WRITE); |
717 | |
718 | blkio_get_key_name(BLKIO_STAT_TOTAL, dev, key_str, MAX_KEY_LEN, false); |
719 | cb->fill(cb, key_str, disk_total); |
720 | return disk_total; |
721 | } |
722 | |
723 | /* This should be called with blkg->stats_lock held */ |
724 | static uint64_t blkio_get_stat(struct blkio_group *blkg, |
725 | struct cgroup_map_cb *cb, dev_t dev, enum stat_type type) |
726 | { |
727 | uint64_t disk_total; |
728 | char key_str[MAX_KEY_LEN]; |
729 | enum stat_sub_type sub_type; |
730 | |
731 | if (type == BLKIO_STAT_TIME) |
732 | return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, |
733 | blkg->stats.time, cb, dev); |
734 | #ifdef CONFIG_DEBUG_BLK_CGROUP |
735 | if (type == BLKIO_STAT_UNACCOUNTED_TIME) |
736 | return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, |
737 | blkg->stats.unaccounted_time, cb, dev); |
738 | if (type == BLKIO_STAT_AVG_QUEUE_SIZE) { |
739 | uint64_t sum = blkg->stats.avg_queue_size_sum; |
740 | uint64_t samples = blkg->stats.avg_queue_size_samples; |
741 | if (samples) |
742 | do_div(sum, samples); |
743 | else |
744 | sum = 0; |
745 | return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, sum, cb, dev); |
746 | } |
747 | if (type == BLKIO_STAT_GROUP_WAIT_TIME) |
748 | return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, |
749 | blkg->stats.group_wait_time, cb, dev); |
750 | if (type == BLKIO_STAT_IDLE_TIME) |
751 | return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, |
752 | blkg->stats.idle_time, cb, dev); |
753 | if (type == BLKIO_STAT_EMPTY_TIME) |
754 | return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, |
755 | blkg->stats.empty_time, cb, dev); |
756 | if (type == BLKIO_STAT_DEQUEUE) |
757 | return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, |
758 | blkg->stats.dequeue, cb, dev); |
759 | #endif |
760 | |
761 | for (sub_type = BLKIO_STAT_READ; sub_type < BLKIO_STAT_TOTAL; |
762 | sub_type++) { |
763 | blkio_get_key_name(sub_type, dev, key_str, MAX_KEY_LEN, false); |
764 | cb->fill(cb, key_str, blkg->stats.stat_arr[type][sub_type]); |
765 | } |
766 | disk_total = blkg->stats.stat_arr[type][BLKIO_STAT_READ] + |
767 | blkg->stats.stat_arr[type][BLKIO_STAT_WRITE]; |
768 | blkio_get_key_name(BLKIO_STAT_TOTAL, dev, key_str, MAX_KEY_LEN, false); |
769 | cb->fill(cb, key_str, disk_total); |
770 | return disk_total; |
771 | } |
772 | |
773 | static int blkio_policy_parse_and_set(char *buf, |
774 | struct blkio_policy_node *newpn, enum blkio_policy_id plid, int fileid) |
775 | { |
776 | struct gendisk *disk = NULL; |
777 | char *s[4], *p, *major_s = NULL, *minor_s = NULL; |
778 | unsigned long major, minor; |
779 | int i = 0, ret = -EINVAL; |
780 | int part; |
781 | dev_t dev; |
782 | u64 temp; |
783 | |
784 | memset(s, 0, sizeof(s)); |
785 | |
786 | while ((p = strsep(&buf, " ")) != NULL) { |
787 | if (!*p) |
788 | continue; |
789 | |
790 | s[i++] = p; |
791 | |
792 | /* Prevent from inputing too many things */ |
793 | if (i == 3) |
794 | break; |
795 | } |
796 | |
797 | if (i != 2) |
798 | goto out; |
799 | |
800 | p = strsep(&s[0], ":"); |
801 | if (p != NULL) |
802 | major_s = p; |
803 | else |
804 | goto out; |
805 | |
806 | minor_s = s[0]; |
807 | if (!minor_s) |
808 | goto out; |
809 | |
810 | if (strict_strtoul(major_s, 10, &major)) |
811 | goto out; |
812 | |
813 | if (strict_strtoul(minor_s, 10, &minor)) |
814 | goto out; |
815 | |
816 | dev = MKDEV(major, minor); |
817 | |
818 | if (strict_strtoull(s[1], 10, &temp)) |
819 | goto out; |
820 | |
821 | /* For rule removal, do not check for device presence. */ |
822 | if (temp) { |
823 | disk = get_gendisk(dev, &part); |
824 | if (!disk || part) { |
825 | ret = -ENODEV; |
826 | goto out; |
827 | } |
828 | } |
829 | |
830 | newpn->dev = dev; |
831 | |
832 | switch (plid) { |
833 | case BLKIO_POLICY_PROP: |
834 | if ((temp < BLKIO_WEIGHT_MIN && temp > 0) || |
835 | temp > BLKIO_WEIGHT_MAX) |
836 | goto out; |
837 | |
838 | newpn->plid = plid; |
839 | newpn->fileid = fileid; |
840 | newpn->val.weight = temp; |
841 | break; |
842 | case BLKIO_POLICY_THROTL: |
843 | switch(fileid) { |
844 | case BLKIO_THROTL_read_bps_device: |
845 | case BLKIO_THROTL_write_bps_device: |
846 | newpn->plid = plid; |
847 | newpn->fileid = fileid; |
848 | newpn->val.bps = temp; |
849 | break; |
850 | case BLKIO_THROTL_read_iops_device: |
851 | case BLKIO_THROTL_write_iops_device: |
852 | if (temp > THROTL_IOPS_MAX) |
853 | goto out; |
854 | |
855 | newpn->plid = plid; |
856 | newpn->fileid = fileid; |
857 | newpn->val.iops = (unsigned int)temp; |
858 | break; |
859 | } |
860 | break; |
861 | default: |
862 | BUG(); |
863 | } |
864 | ret = 0; |
865 | out: |
866 | put_disk(disk); |
867 | return ret; |
868 | } |
869 | |
870 | unsigned int blkcg_get_weight(struct blkio_cgroup *blkcg, |
871 | dev_t dev) |
872 | { |
873 | struct blkio_policy_node *pn; |
874 | unsigned long flags; |
875 | unsigned int weight; |
876 | |
877 | spin_lock_irqsave(&blkcg->lock, flags); |
878 | |
879 | pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_PROP, |
880 | BLKIO_PROP_weight_device); |
881 | if (pn) |
882 | weight = pn->val.weight; |
883 | else |
884 | weight = blkcg->weight; |
885 | |
886 | spin_unlock_irqrestore(&blkcg->lock, flags); |
887 | |
888 | return weight; |
889 | } |
890 | EXPORT_SYMBOL_GPL(blkcg_get_weight); |
891 | |
892 | uint64_t blkcg_get_read_bps(struct blkio_cgroup *blkcg, dev_t dev) |
893 | { |
894 | struct blkio_policy_node *pn; |
895 | unsigned long flags; |
896 | uint64_t bps = -1; |
897 | |
898 | spin_lock_irqsave(&blkcg->lock, flags); |
899 | pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL, |
900 | BLKIO_THROTL_read_bps_device); |
901 | if (pn) |
902 | bps = pn->val.bps; |
903 | spin_unlock_irqrestore(&blkcg->lock, flags); |
904 | |
905 | return bps; |
906 | } |
907 | |
908 | uint64_t blkcg_get_write_bps(struct blkio_cgroup *blkcg, dev_t dev) |
909 | { |
910 | struct blkio_policy_node *pn; |
911 | unsigned long flags; |
912 | uint64_t bps = -1; |
913 | |
914 | spin_lock_irqsave(&blkcg->lock, flags); |
915 | pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL, |
916 | BLKIO_THROTL_write_bps_device); |
917 | if (pn) |
918 | bps = pn->val.bps; |
919 | spin_unlock_irqrestore(&blkcg->lock, flags); |
920 | |
921 | return bps; |
922 | } |
923 | |
924 | unsigned int blkcg_get_read_iops(struct blkio_cgroup *blkcg, dev_t dev) |
925 | { |
926 | struct blkio_policy_node *pn; |
927 | unsigned long flags; |
928 | unsigned int iops = -1; |
929 | |
930 | spin_lock_irqsave(&blkcg->lock, flags); |
931 | pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL, |
932 | BLKIO_THROTL_read_iops_device); |
933 | if (pn) |
934 | iops = pn->val.iops; |
935 | spin_unlock_irqrestore(&blkcg->lock, flags); |
936 | |
937 | return iops; |
938 | } |
939 | |
940 | unsigned int blkcg_get_write_iops(struct blkio_cgroup *blkcg, dev_t dev) |
941 | { |
942 | struct blkio_policy_node *pn; |
943 | unsigned long flags; |
944 | unsigned int iops = -1; |
945 | |
946 | spin_lock_irqsave(&blkcg->lock, flags); |
947 | pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL, |
948 | BLKIO_THROTL_write_iops_device); |
949 | if (pn) |
950 | iops = pn->val.iops; |
951 | spin_unlock_irqrestore(&blkcg->lock, flags); |
952 | |
953 | return iops; |
954 | } |
955 | |
956 | /* Checks whether user asked for deleting a policy rule */ |
957 | static bool blkio_delete_rule_command(struct blkio_policy_node *pn) |
958 | { |
959 | switch(pn->plid) { |
960 | case BLKIO_POLICY_PROP: |
961 | if (pn->val.weight == 0) |
962 | return 1; |
963 | break; |
964 | case BLKIO_POLICY_THROTL: |
965 | switch(pn->fileid) { |
966 | case BLKIO_THROTL_read_bps_device: |
967 | case BLKIO_THROTL_write_bps_device: |
968 | if (pn->val.bps == 0) |
969 | return 1; |
970 | break; |
971 | case BLKIO_THROTL_read_iops_device: |
972 | case BLKIO_THROTL_write_iops_device: |
973 | if (pn->val.iops == 0) |
974 | return 1; |
975 | } |
976 | break; |
977 | default: |
978 | BUG(); |
979 | } |
980 | |
981 | return 0; |
982 | } |
983 | |
984 | static void blkio_update_policy_rule(struct blkio_policy_node *oldpn, |
985 | struct blkio_policy_node *newpn) |
986 | { |
987 | switch(oldpn->plid) { |
988 | case BLKIO_POLICY_PROP: |
989 | oldpn->val.weight = newpn->val.weight; |
990 | break; |
991 | case BLKIO_POLICY_THROTL: |
992 | switch(newpn->fileid) { |
993 | case BLKIO_THROTL_read_bps_device: |
994 | case BLKIO_THROTL_write_bps_device: |
995 | oldpn->val.bps = newpn->val.bps; |
996 | break; |
997 | case BLKIO_THROTL_read_iops_device: |
998 | case BLKIO_THROTL_write_iops_device: |
999 | oldpn->val.iops = newpn->val.iops; |
1000 | } |
1001 | break; |
1002 | default: |
1003 | BUG(); |
1004 | } |
1005 | } |
1006 | |
1007 | /* |
1008 | * Some rules/values in blkg have changed. Propagate those to respective |
1009 | * policies. |
1010 | */ |
1011 | static void blkio_update_blkg_policy(struct blkio_cgroup *blkcg, |
1012 | struct blkio_group *blkg, struct blkio_policy_node *pn) |
1013 | { |
1014 | unsigned int weight, iops; |
1015 | u64 bps; |
1016 | |
1017 | switch(pn->plid) { |
1018 | case BLKIO_POLICY_PROP: |
1019 | weight = pn->val.weight ? pn->val.weight : |
1020 | blkcg->weight; |
1021 | blkio_update_group_weight(blkg, weight); |
1022 | break; |
1023 | case BLKIO_POLICY_THROTL: |
1024 | switch(pn->fileid) { |
1025 | case BLKIO_THROTL_read_bps_device: |
1026 | case BLKIO_THROTL_write_bps_device: |
1027 | bps = pn->val.bps ? pn->val.bps : (-1); |
1028 | blkio_update_group_bps(blkg, bps, pn->fileid); |
1029 | break; |
1030 | case BLKIO_THROTL_read_iops_device: |
1031 | case BLKIO_THROTL_write_iops_device: |
1032 | iops = pn->val.iops ? pn->val.iops : (-1); |
1033 | blkio_update_group_iops(blkg, iops, pn->fileid); |
1034 | break; |
1035 | } |
1036 | break; |
1037 | default: |
1038 | BUG(); |
1039 | } |
1040 | } |
1041 | |
1042 | /* |
1043 | * A policy node rule has been updated. Propagate this update to all the |
1044 | * block groups which might be affected by this update. |
1045 | */ |
1046 | static void blkio_update_policy_node_blkg(struct blkio_cgroup *blkcg, |
1047 | struct blkio_policy_node *pn) |
1048 | { |
1049 | struct blkio_group *blkg; |
1050 | struct hlist_node *n; |
1051 | |
1052 | spin_lock(&blkio_list_lock); |
1053 | spin_lock_irq(&blkcg->lock); |
1054 | |
1055 | hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) { |
1056 | if (pn->dev != blkg->dev || pn->plid != blkg->plid) |
1057 | continue; |
1058 | blkio_update_blkg_policy(blkcg, blkg, pn); |
1059 | } |
1060 | |
1061 | spin_unlock_irq(&blkcg->lock); |
1062 | spin_unlock(&blkio_list_lock); |
1063 | } |
1064 | |
1065 | static int blkiocg_file_write(struct cgroup *cgrp, struct cftype *cft, |
1066 | const char *buffer) |
1067 | { |
1068 | int ret = 0; |
1069 | char *buf; |
1070 | struct blkio_policy_node *newpn, *pn; |
1071 | struct blkio_cgroup *blkcg; |
1072 | int keep_newpn = 0; |
1073 | enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); |
1074 | int fileid = BLKIOFILE_ATTR(cft->private); |
1075 | |
1076 | buf = kstrdup(buffer, GFP_KERNEL); |
1077 | if (!buf) |
1078 | return -ENOMEM; |
1079 | |
1080 | newpn = kzalloc(sizeof(*newpn), GFP_KERNEL); |
1081 | if (!newpn) { |
1082 | ret = -ENOMEM; |
1083 | goto free_buf; |
1084 | } |
1085 | |
1086 | ret = blkio_policy_parse_and_set(buf, newpn, plid, fileid); |
1087 | if (ret) |
1088 | goto free_newpn; |
1089 | |
1090 | blkcg = cgroup_to_blkio_cgroup(cgrp); |
1091 | |
1092 | spin_lock_irq(&blkcg->lock); |
1093 | |
1094 | pn = blkio_policy_search_node(blkcg, newpn->dev, plid, fileid); |
1095 | if (!pn) { |
1096 | if (!blkio_delete_rule_command(newpn)) { |
1097 | blkio_policy_insert_node(blkcg, newpn); |
1098 | keep_newpn = 1; |
1099 | } |
1100 | spin_unlock_irq(&blkcg->lock); |
1101 | goto update_io_group; |
1102 | } |
1103 | |
1104 | if (blkio_delete_rule_command(newpn)) { |
1105 | blkio_policy_delete_node(pn); |
1106 | kfree(pn); |
1107 | spin_unlock_irq(&blkcg->lock); |
1108 | goto update_io_group; |
1109 | } |
1110 | spin_unlock_irq(&blkcg->lock); |
1111 | |
1112 | blkio_update_policy_rule(pn, newpn); |
1113 | |
1114 | update_io_group: |
1115 | blkio_update_policy_node_blkg(blkcg, newpn); |
1116 | |
1117 | free_newpn: |
1118 | if (!keep_newpn) |
1119 | kfree(newpn); |
1120 | free_buf: |
1121 | kfree(buf); |
1122 | return ret; |
1123 | } |
1124 | |
1125 | static void |
1126 | blkio_print_policy_node(struct seq_file *m, struct blkio_policy_node *pn) |
1127 | { |
1128 | switch(pn->plid) { |
1129 | case BLKIO_POLICY_PROP: |
1130 | if (pn->fileid == BLKIO_PROP_weight_device) |
1131 | seq_printf(m, "%u:%u\t%u\n", MAJOR(pn->dev), |
1132 | MINOR(pn->dev), pn->val.weight); |
1133 | break; |
1134 | case BLKIO_POLICY_THROTL: |
1135 | switch(pn->fileid) { |
1136 | case BLKIO_THROTL_read_bps_device: |
1137 | case BLKIO_THROTL_write_bps_device: |
1138 | seq_printf(m, "%u:%u\t%llu\n", MAJOR(pn->dev), |
1139 | MINOR(pn->dev), pn->val.bps); |
1140 | break; |
1141 | case BLKIO_THROTL_read_iops_device: |
1142 | case BLKIO_THROTL_write_iops_device: |
1143 | seq_printf(m, "%u:%u\t%u\n", MAJOR(pn->dev), |
1144 | MINOR(pn->dev), pn->val.iops); |
1145 | break; |
1146 | } |
1147 | break; |
1148 | default: |
1149 | BUG(); |
1150 | } |
1151 | } |
1152 | |
1153 | /* cgroup files which read their data from policy nodes end up here */ |
1154 | static void blkio_read_policy_node_files(struct cftype *cft, |
1155 | struct blkio_cgroup *blkcg, struct seq_file *m) |
1156 | { |
1157 | struct blkio_policy_node *pn; |
1158 | |
1159 | if (!list_empty(&blkcg->policy_list)) { |
1160 | spin_lock_irq(&blkcg->lock); |
1161 | list_for_each_entry(pn, &blkcg->policy_list, node) { |
1162 | if (!pn_matches_cftype(cft, pn)) |
1163 | continue; |
1164 | blkio_print_policy_node(m, pn); |
1165 | } |
1166 | spin_unlock_irq(&blkcg->lock); |
1167 | } |
1168 | } |
1169 | |
1170 | static int blkiocg_file_read(struct cgroup *cgrp, struct cftype *cft, |
1171 | struct seq_file *m) |
1172 | { |
1173 | struct blkio_cgroup *blkcg; |
1174 | enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); |
1175 | int name = BLKIOFILE_ATTR(cft->private); |
1176 | |
1177 | blkcg = cgroup_to_blkio_cgroup(cgrp); |
1178 | |
1179 | switch(plid) { |
1180 | case BLKIO_POLICY_PROP: |
1181 | switch(name) { |
1182 | case BLKIO_PROP_weight_device: |
1183 | blkio_read_policy_node_files(cft, blkcg, m); |
1184 | return 0; |
1185 | default: |
1186 | BUG(); |
1187 | } |
1188 | break; |
1189 | case BLKIO_POLICY_THROTL: |
1190 | switch(name){ |
1191 | case BLKIO_THROTL_read_bps_device: |
1192 | case BLKIO_THROTL_write_bps_device: |
1193 | case BLKIO_THROTL_read_iops_device: |
1194 | case BLKIO_THROTL_write_iops_device: |
1195 | blkio_read_policy_node_files(cft, blkcg, m); |
1196 | return 0; |
1197 | default: |
1198 | BUG(); |
1199 | } |
1200 | break; |
1201 | default: |
1202 | BUG(); |
1203 | } |
1204 | |
1205 | return 0; |
1206 | } |
1207 | |
1208 | static int blkio_read_blkg_stats(struct blkio_cgroup *blkcg, |
1209 | struct cftype *cft, struct cgroup_map_cb *cb, |
1210 | enum stat_type type, bool show_total, bool pcpu) |
1211 | { |
1212 | struct blkio_group *blkg; |
1213 | struct hlist_node *n; |
1214 | uint64_t cgroup_total = 0; |
1215 | |
1216 | rcu_read_lock(); |
1217 | hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) { |
1218 | if (blkg->dev) { |
1219 | if (!cftype_blkg_same_policy(cft, blkg)) |
1220 | continue; |
1221 | if (pcpu) |
1222 | cgroup_total += blkio_get_stat_cpu(blkg, cb, |
1223 | blkg->dev, type); |
1224 | else { |
1225 | spin_lock_irq(&blkg->stats_lock); |
1226 | cgroup_total += blkio_get_stat(blkg, cb, |
1227 | blkg->dev, type); |
1228 | spin_unlock_irq(&blkg->stats_lock); |
1229 | } |
1230 | } |
1231 | } |
1232 | if (show_total) |
1233 | cb->fill(cb, "Total", cgroup_total); |
1234 | rcu_read_unlock(); |
1235 | return 0; |
1236 | } |
1237 | |
1238 | /* All map kind of cgroup file get serviced by this function */ |
1239 | static int blkiocg_file_read_map(struct cgroup *cgrp, struct cftype *cft, |
1240 | struct cgroup_map_cb *cb) |
1241 | { |
1242 | struct blkio_cgroup *blkcg; |
1243 | enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); |
1244 | int name = BLKIOFILE_ATTR(cft->private); |
1245 | |
1246 | blkcg = cgroup_to_blkio_cgroup(cgrp); |
1247 | |
1248 | switch(plid) { |
1249 | case BLKIO_POLICY_PROP: |
1250 | switch(name) { |
1251 | case BLKIO_PROP_time: |
1252 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1253 | BLKIO_STAT_TIME, 0, 0); |
1254 | case BLKIO_PROP_sectors: |
1255 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1256 | BLKIO_STAT_CPU_SECTORS, 0, 1); |
1257 | case BLKIO_PROP_io_service_bytes: |
1258 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1259 | BLKIO_STAT_CPU_SERVICE_BYTES, 1, 1); |
1260 | case BLKIO_PROP_io_serviced: |
1261 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1262 | BLKIO_STAT_CPU_SERVICED, 1, 1); |
1263 | case BLKIO_PROP_io_service_time: |
1264 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1265 | BLKIO_STAT_SERVICE_TIME, 1, 0); |
1266 | case BLKIO_PROP_io_wait_time: |
1267 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1268 | BLKIO_STAT_WAIT_TIME, 1, 0); |
1269 | case BLKIO_PROP_io_merged: |
1270 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1271 | BLKIO_STAT_CPU_MERGED, 1, 1); |
1272 | case BLKIO_PROP_io_queued: |
1273 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1274 | BLKIO_STAT_QUEUED, 1, 0); |
1275 | #ifdef CONFIG_DEBUG_BLK_CGROUP |
1276 | case BLKIO_PROP_unaccounted_time: |
1277 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1278 | BLKIO_STAT_UNACCOUNTED_TIME, 0, 0); |
1279 | case BLKIO_PROP_dequeue: |
1280 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1281 | BLKIO_STAT_DEQUEUE, 0, 0); |
1282 | case BLKIO_PROP_avg_queue_size: |
1283 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1284 | BLKIO_STAT_AVG_QUEUE_SIZE, 0, 0); |
1285 | case BLKIO_PROP_group_wait_time: |
1286 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1287 | BLKIO_STAT_GROUP_WAIT_TIME, 0, 0); |
1288 | case BLKIO_PROP_idle_time: |
1289 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1290 | BLKIO_STAT_IDLE_TIME, 0, 0); |
1291 | case BLKIO_PROP_empty_time: |
1292 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1293 | BLKIO_STAT_EMPTY_TIME, 0, 0); |
1294 | #endif |
1295 | default: |
1296 | BUG(); |
1297 | } |
1298 | break; |
1299 | case BLKIO_POLICY_THROTL: |
1300 | switch(name){ |
1301 | case BLKIO_THROTL_io_service_bytes: |
1302 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1303 | BLKIO_STAT_CPU_SERVICE_BYTES, 1, 1); |
1304 | case BLKIO_THROTL_io_serviced: |
1305 | return blkio_read_blkg_stats(blkcg, cft, cb, |
1306 | BLKIO_STAT_CPU_SERVICED, 1, 1); |
1307 | default: |
1308 | BUG(); |
1309 | } |
1310 | break; |
1311 | default: |
1312 | BUG(); |
1313 | } |
1314 | |
1315 | return 0; |
1316 | } |
1317 | |
1318 | static int blkio_weight_write(struct blkio_cgroup *blkcg, u64 val) |
1319 | { |
1320 | struct blkio_group *blkg; |
1321 | struct hlist_node *n; |
1322 | struct blkio_policy_node *pn; |
1323 | |
1324 | if (val < BLKIO_WEIGHT_MIN || val > BLKIO_WEIGHT_MAX) |
1325 | return -EINVAL; |
1326 | |
1327 | spin_lock(&blkio_list_lock); |
1328 | spin_lock_irq(&blkcg->lock); |
1329 | blkcg->weight = (unsigned int)val; |
1330 | |
1331 | hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) { |
1332 | pn = blkio_policy_search_node(blkcg, blkg->dev, |
1333 | BLKIO_POLICY_PROP, BLKIO_PROP_weight_device); |
1334 | if (pn) |
1335 | continue; |
1336 | |
1337 | blkio_update_group_weight(blkg, blkcg->weight); |
1338 | } |
1339 | spin_unlock_irq(&blkcg->lock); |
1340 | spin_unlock(&blkio_list_lock); |
1341 | return 0; |
1342 | } |
1343 | |
1344 | static u64 blkiocg_file_read_u64 (struct cgroup *cgrp, struct cftype *cft) { |
1345 | struct blkio_cgroup *blkcg; |
1346 | enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); |
1347 | int name = BLKIOFILE_ATTR(cft->private); |
1348 | |
1349 | blkcg = cgroup_to_blkio_cgroup(cgrp); |
1350 | |
1351 | switch(plid) { |
1352 | case BLKIO_POLICY_PROP: |
1353 | switch(name) { |
1354 | case BLKIO_PROP_weight: |
1355 | return (u64)blkcg->weight; |
1356 | } |
1357 | break; |
1358 | default: |
1359 | BUG(); |
1360 | } |
1361 | return 0; |
1362 | } |
1363 | |
1364 | static int |
1365 | blkiocg_file_write_u64(struct cgroup *cgrp, struct cftype *cft, u64 val) |
1366 | { |
1367 | struct blkio_cgroup *blkcg; |
1368 | enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private); |
1369 | int name = BLKIOFILE_ATTR(cft->private); |
1370 | |
1371 | blkcg = cgroup_to_blkio_cgroup(cgrp); |
1372 | |
1373 | switch(plid) { |
1374 | case BLKIO_POLICY_PROP: |
1375 | switch(name) { |
1376 | case BLKIO_PROP_weight: |
1377 | return blkio_weight_write(blkcg, val); |
1378 | } |
1379 | break; |
1380 | default: |
1381 | BUG(); |
1382 | } |
1383 | |
1384 | return 0; |
1385 | } |
1386 | |
1387 | struct cftype blkio_files[] = { |
1388 | { |
1389 | .name = "weight_device", |
1390 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1391 | BLKIO_PROP_weight_device), |
1392 | .read_seq_string = blkiocg_file_read, |
1393 | .write_string = blkiocg_file_write, |
1394 | .max_write_len = 256, |
1395 | }, |
1396 | { |
1397 | .name = "weight", |
1398 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1399 | BLKIO_PROP_weight), |
1400 | .read_u64 = blkiocg_file_read_u64, |
1401 | .write_u64 = blkiocg_file_write_u64, |
1402 | }, |
1403 | { |
1404 | .name = "time", |
1405 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1406 | BLKIO_PROP_time), |
1407 | .read_map = blkiocg_file_read_map, |
1408 | }, |
1409 | { |
1410 | .name = "sectors", |
1411 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1412 | BLKIO_PROP_sectors), |
1413 | .read_map = blkiocg_file_read_map, |
1414 | }, |
1415 | { |
1416 | .name = "io_service_bytes", |
1417 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1418 | BLKIO_PROP_io_service_bytes), |
1419 | .read_map = blkiocg_file_read_map, |
1420 | }, |
1421 | { |
1422 | .name = "io_serviced", |
1423 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1424 | BLKIO_PROP_io_serviced), |
1425 | .read_map = blkiocg_file_read_map, |
1426 | }, |
1427 | { |
1428 | .name = "io_service_time", |
1429 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1430 | BLKIO_PROP_io_service_time), |
1431 | .read_map = blkiocg_file_read_map, |
1432 | }, |
1433 | { |
1434 | .name = "io_wait_time", |
1435 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1436 | BLKIO_PROP_io_wait_time), |
1437 | .read_map = blkiocg_file_read_map, |
1438 | }, |
1439 | { |
1440 | .name = "io_merged", |
1441 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1442 | BLKIO_PROP_io_merged), |
1443 | .read_map = blkiocg_file_read_map, |
1444 | }, |
1445 | { |
1446 | .name = "io_queued", |
1447 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1448 | BLKIO_PROP_io_queued), |
1449 | .read_map = blkiocg_file_read_map, |
1450 | }, |
1451 | { |
1452 | .name = "reset_stats", |
1453 | .write_u64 = blkiocg_reset_stats, |
1454 | }, |
1455 | #ifdef CONFIG_BLK_DEV_THROTTLING |
1456 | { |
1457 | .name = "throttle.read_bps_device", |
1458 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, |
1459 | BLKIO_THROTL_read_bps_device), |
1460 | .read_seq_string = blkiocg_file_read, |
1461 | .write_string = blkiocg_file_write, |
1462 | .max_write_len = 256, |
1463 | }, |
1464 | |
1465 | { |
1466 | .name = "throttle.write_bps_device", |
1467 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, |
1468 | BLKIO_THROTL_write_bps_device), |
1469 | .read_seq_string = blkiocg_file_read, |
1470 | .write_string = blkiocg_file_write, |
1471 | .max_write_len = 256, |
1472 | }, |
1473 | |
1474 | { |
1475 | .name = "throttle.read_iops_device", |
1476 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, |
1477 | BLKIO_THROTL_read_iops_device), |
1478 | .read_seq_string = blkiocg_file_read, |
1479 | .write_string = blkiocg_file_write, |
1480 | .max_write_len = 256, |
1481 | }, |
1482 | |
1483 | { |
1484 | .name = "throttle.write_iops_device", |
1485 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, |
1486 | BLKIO_THROTL_write_iops_device), |
1487 | .read_seq_string = blkiocg_file_read, |
1488 | .write_string = blkiocg_file_write, |
1489 | .max_write_len = 256, |
1490 | }, |
1491 | { |
1492 | .name = "throttle.io_service_bytes", |
1493 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, |
1494 | BLKIO_THROTL_io_service_bytes), |
1495 | .read_map = blkiocg_file_read_map, |
1496 | }, |
1497 | { |
1498 | .name = "throttle.io_serviced", |
1499 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL, |
1500 | BLKIO_THROTL_io_serviced), |
1501 | .read_map = blkiocg_file_read_map, |
1502 | }, |
1503 | #endif /* CONFIG_BLK_DEV_THROTTLING */ |
1504 | |
1505 | #ifdef CONFIG_DEBUG_BLK_CGROUP |
1506 | { |
1507 | .name = "avg_queue_size", |
1508 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1509 | BLKIO_PROP_avg_queue_size), |
1510 | .read_map = blkiocg_file_read_map, |
1511 | }, |
1512 | { |
1513 | .name = "group_wait_time", |
1514 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1515 | BLKIO_PROP_group_wait_time), |
1516 | .read_map = blkiocg_file_read_map, |
1517 | }, |
1518 | { |
1519 | .name = "idle_time", |
1520 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1521 | BLKIO_PROP_idle_time), |
1522 | .read_map = blkiocg_file_read_map, |
1523 | }, |
1524 | { |
1525 | .name = "empty_time", |
1526 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1527 | BLKIO_PROP_empty_time), |
1528 | .read_map = blkiocg_file_read_map, |
1529 | }, |
1530 | { |
1531 | .name = "dequeue", |
1532 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1533 | BLKIO_PROP_dequeue), |
1534 | .read_map = blkiocg_file_read_map, |
1535 | }, |
1536 | { |
1537 | .name = "unaccounted_time", |
1538 | .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP, |
1539 | BLKIO_PROP_unaccounted_time), |
1540 | .read_map = blkiocg_file_read_map, |
1541 | }, |
1542 | #endif |
1543 | }; |
1544 | |
1545 | static int blkiocg_populate(struct cgroup_subsys *subsys, struct cgroup *cgroup) |
1546 | { |
1547 | return cgroup_add_files(cgroup, subsys, blkio_files, |
1548 | ARRAY_SIZE(blkio_files)); |
1549 | } |
1550 | |
1551 | static void blkiocg_destroy(struct cgroup_subsys *subsys, struct cgroup *cgroup) |
1552 | { |
1553 | struct blkio_cgroup *blkcg = cgroup_to_blkio_cgroup(cgroup); |
1554 | unsigned long flags; |
1555 | struct blkio_group *blkg; |
1556 | void *key; |
1557 | struct blkio_policy_type *blkiop; |
1558 | struct blkio_policy_node *pn, *pntmp; |
1559 | |
1560 | rcu_read_lock(); |
1561 | do { |
1562 | spin_lock_irqsave(&blkcg->lock, flags); |
1563 | |
1564 | if (hlist_empty(&blkcg->blkg_list)) { |
1565 | spin_unlock_irqrestore(&blkcg->lock, flags); |
1566 | break; |
1567 | } |
1568 | |
1569 | blkg = hlist_entry(blkcg->blkg_list.first, struct blkio_group, |
1570 | blkcg_node); |
1571 | key = rcu_dereference(blkg->key); |
1572 | __blkiocg_del_blkio_group(blkg); |
1573 | |
1574 | spin_unlock_irqrestore(&blkcg->lock, flags); |
1575 | |
1576 | /* |
1577 | * This blkio_group is being unlinked as associated cgroup is |
1578 | * going away. Let all the IO controlling policies know about |
1579 | * this event. |
1580 | */ |
1581 | spin_lock(&blkio_list_lock); |
1582 | list_for_each_entry(blkiop, &blkio_list, list) { |
1583 | if (blkiop->plid != blkg->plid) |
1584 | continue; |
1585 | blkiop->ops.blkio_unlink_group_fn(key, blkg); |
1586 | } |
1587 | spin_unlock(&blkio_list_lock); |
1588 | } while (1); |
1589 | |
1590 | list_for_each_entry_safe(pn, pntmp, &blkcg->policy_list, node) { |
1591 | blkio_policy_delete_node(pn); |
1592 | kfree(pn); |
1593 | } |
1594 | |
1595 | free_css_id(&blkio_subsys, &blkcg->css); |
1596 | rcu_read_unlock(); |
1597 | if (blkcg != &blkio_root_cgroup) |
1598 | kfree(blkcg); |
1599 | } |
1600 | |
1601 | static struct cgroup_subsys_state * |
1602 | blkiocg_create(struct cgroup_subsys *subsys, struct cgroup *cgroup) |
1603 | { |
1604 | struct blkio_cgroup *blkcg; |
1605 | struct cgroup *parent = cgroup->parent; |
1606 | |
1607 | if (!parent) { |
1608 | blkcg = &blkio_root_cgroup; |
1609 | goto done; |
1610 | } |
1611 | |
1612 | blkcg = kzalloc(sizeof(*blkcg), GFP_KERNEL); |
1613 | if (!blkcg) |
1614 | return ERR_PTR(-ENOMEM); |
1615 | |
1616 | blkcg->weight = BLKIO_WEIGHT_DEFAULT; |
1617 | done: |
1618 | spin_lock_init(&blkcg->lock); |
1619 | INIT_HLIST_HEAD(&blkcg->blkg_list); |
1620 | |
1621 | INIT_LIST_HEAD(&blkcg->policy_list); |
1622 | return &blkcg->css; |
1623 | } |
1624 | |
1625 | /* |
1626 | * We cannot support shared io contexts, as we have no mean to support |
1627 | * two tasks with the same ioc in two different groups without major rework |
1628 | * of the main cic data structures. For now we allow a task to change |
1629 | * its cgroup only if it's the only owner of its ioc. |
1630 | */ |
1631 | static int blkiocg_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, |
1632 | struct cgroup_taskset *tset) |
1633 | { |
1634 | struct task_struct *task; |
1635 | struct io_context *ioc; |
1636 | int ret = 0; |
1637 | |
1638 | /* task_lock() is needed to avoid races with exit_io_context() */ |
1639 | cgroup_taskset_for_each(task, cgrp, tset) { |
1640 | task_lock(task); |
1641 | ioc = task->io_context; |
1642 | if (ioc && atomic_read(&ioc->nr_tasks) > 1) |
1643 | ret = -EINVAL; |
1644 | task_unlock(task); |
1645 | if (ret) |
1646 | break; |
1647 | } |
1648 | return ret; |
1649 | } |
1650 | |
1651 | static void blkiocg_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, |
1652 | struct cgroup_taskset *tset) |
1653 | { |
1654 | struct task_struct *task; |
1655 | struct io_context *ioc; |
1656 | |
1657 | cgroup_taskset_for_each(task, cgrp, tset) { |
1658 | /* we don't lose anything even if ioc allocation fails */ |
1659 | ioc = get_task_io_context(task, GFP_ATOMIC, NUMA_NO_NODE); |
1660 | if (ioc) { |
1661 | ioc_cgroup_changed(ioc); |
1662 | put_io_context(ioc); |
1663 | } |
1664 | } |
1665 | } |
1666 | |
1667 | void blkio_policy_register(struct blkio_policy_type *blkiop) |
1668 | { |
1669 | spin_lock(&blkio_list_lock); |
1670 | list_add_tail(&blkiop->list, &blkio_list); |
1671 | spin_unlock(&blkio_list_lock); |
1672 | } |
1673 | EXPORT_SYMBOL_GPL(blkio_policy_register); |
1674 | |
1675 | void blkio_policy_unregister(struct blkio_policy_type *blkiop) |
1676 | { |
1677 | spin_lock(&blkio_list_lock); |
1678 | list_del_init(&blkiop->list); |
1679 | spin_unlock(&blkio_list_lock); |
1680 | } |
1681 | EXPORT_SYMBOL_GPL(blkio_policy_unregister); |
1682 | |
1683 | static int __init init_cgroup_blkio(void) |
1684 | { |
1685 | return cgroup_load_subsys(&blkio_subsys); |
1686 | } |
1687 | |
1688 | static void __exit exit_cgroup_blkio(void) |
1689 | { |
1690 | cgroup_unload_subsys(&blkio_subsys); |
1691 | } |
1692 | |
1693 | module_init(init_cgroup_blkio); |
1694 | module_exit(exit_cgroup_blkio); |
1695 | MODULE_LICENSE("GPL"); |
1696 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9