Commit | Line | Data |
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3bd94003 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
fd2ed4d2 MP |
2 | #include <linux/errno.h> |
3 | #include <linux/numa.h> | |
4 | #include <linux/slab.h> | |
5 | #include <linux/rculist.h> | |
6 | #include <linux/threads.h> | |
7 | #include <linux/preempt.h> | |
8 | #include <linux/irqflags.h> | |
9 | #include <linux/vmalloc.h> | |
10 | #include <linux/mm.h> | |
11 | #include <linux/module.h> | |
12 | #include <linux/device-mapper.h> | |
13 | ||
4cc96131 | 14 | #include "dm-core.h" |
fd2ed4d2 MP |
15 | #include "dm-stats.h" |
16 | ||
17 | #define DM_MSG_PREFIX "stats" | |
18 | ||
19 | static int dm_stat_need_rcu_barrier; | |
20 | ||
21 | /* | |
22 | * Using 64-bit values to avoid overflow (which is a | |
23 | * problem that block/genhd.c's IO accounting has). | |
24 | */ | |
25 | struct dm_stat_percpu { | |
26 | unsigned long long sectors[2]; | |
27 | unsigned long long ios[2]; | |
28 | unsigned long long merges[2]; | |
29 | unsigned long long ticks[2]; | |
30 | unsigned long long io_ticks[2]; | |
31 | unsigned long long io_ticks_total; | |
32 | unsigned long long time_in_queue; | |
dfcfac3e | 33 | unsigned long long *histogram; |
fd2ed4d2 MP |
34 | }; |
35 | ||
36 | struct dm_stat_shared { | |
37 | atomic_t in_flight[2]; | |
c96aec34 | 38 | unsigned long long stamp; |
fd2ed4d2 MP |
39 | struct dm_stat_percpu tmp; |
40 | }; | |
41 | ||
42 | struct dm_stat { | |
43 | struct list_head list_entry; | |
44 | int id; | |
86a3238c | 45 | unsigned int stat_flags; |
fd2ed4d2 MP |
46 | size_t n_entries; |
47 | sector_t start; | |
48 | sector_t end; | |
49 | sector_t step; | |
86a3238c | 50 | unsigned int n_histogram_entries; |
dfcfac3e | 51 | unsigned long long *histogram_boundaries; |
fd2ed4d2 MP |
52 | const char *program_id; |
53 | const char *aux_data; | |
54 | struct rcu_head rcu_head; | |
55 | size_t shared_alloc_size; | |
56 | size_t percpu_alloc_size; | |
dfcfac3e | 57 | size_t histogram_alloc_size; |
fd2ed4d2 | 58 | struct dm_stat_percpu *stat_percpu[NR_CPUS]; |
b18ae8dd | 59 | struct dm_stat_shared stat_shared[]; |
fd2ed4d2 MP |
60 | }; |
61 | ||
c96aec34 MP |
62 | #define STAT_PRECISE_TIMESTAMPS 1 |
63 | ||
fd2ed4d2 MP |
64 | struct dm_stats_last_position { |
65 | sector_t last_sector; | |
86a3238c | 66 | unsigned int last_rw; |
fd2ed4d2 MP |
67 | }; |
68 | ||
69 | /* | |
70 | * A typo on the command line could possibly make the kernel run out of memory | |
71 | * and crash. To prevent the crash we account all used memory. We fail if we | |
72 | * exhaust 1/4 of all memory or 1/2 of vmalloc space. | |
73 | */ | |
74 | #define DM_STATS_MEMORY_FACTOR 4 | |
75 | #define DM_STATS_VMALLOC_FACTOR 2 | |
76 | ||
77 | static DEFINE_SPINLOCK(shared_memory_lock); | |
78 | ||
79 | static unsigned long shared_memory_amount; | |
80 | ||
81 | static bool __check_shared_memory(size_t alloc_size) | |
82 | { | |
83 | size_t a; | |
84 | ||
85 | a = shared_memory_amount + alloc_size; | |
86 | if (a < shared_memory_amount) | |
87 | return false; | |
ca79b0c2 | 88 | if (a >> PAGE_SHIFT > totalram_pages() / DM_STATS_MEMORY_FACTOR) |
fd2ed4d2 MP |
89 | return false; |
90 | #ifdef CONFIG_MMU | |
91 | if (a > (VMALLOC_END - VMALLOC_START) / DM_STATS_VMALLOC_FACTOR) | |
92 | return false; | |
93 | #endif | |
94 | return true; | |
95 | } | |
96 | ||
97 | static bool check_shared_memory(size_t alloc_size) | |
98 | { | |
99 | bool ret; | |
100 | ||
101 | spin_lock_irq(&shared_memory_lock); | |
102 | ||
103 | ret = __check_shared_memory(alloc_size); | |
104 | ||
105 | spin_unlock_irq(&shared_memory_lock); | |
106 | ||
107 | return ret; | |
108 | } | |
109 | ||
110 | static bool claim_shared_memory(size_t alloc_size) | |
111 | { | |
112 | spin_lock_irq(&shared_memory_lock); | |
113 | ||
114 | if (!__check_shared_memory(alloc_size)) { | |
115 | spin_unlock_irq(&shared_memory_lock); | |
116 | return false; | |
117 | } | |
118 | ||
119 | shared_memory_amount += alloc_size; | |
120 | ||
121 | spin_unlock_irq(&shared_memory_lock); | |
122 | ||
123 | return true; | |
124 | } | |
125 | ||
126 | static void free_shared_memory(size_t alloc_size) | |
127 | { | |
128 | unsigned long flags; | |
129 | ||
130 | spin_lock_irqsave(&shared_memory_lock, flags); | |
131 | ||
132 | if (WARN_ON_ONCE(shared_memory_amount < alloc_size)) { | |
133 | spin_unlock_irqrestore(&shared_memory_lock, flags); | |
134 | DMCRIT("Memory usage accounting bug."); | |
135 | return; | |
136 | } | |
137 | ||
138 | shared_memory_amount -= alloc_size; | |
139 | ||
140 | spin_unlock_irqrestore(&shared_memory_lock, flags); | |
141 | } | |
142 | ||
143 | static void *dm_kvzalloc(size_t alloc_size, int node) | |
144 | { | |
145 | void *p; | |
146 | ||
147 | if (!claim_shared_memory(alloc_size)) | |
148 | return NULL; | |
149 | ||
a7c3e901 | 150 | p = kvzalloc_node(alloc_size, GFP_KERNEL | __GFP_NOMEMALLOC, node); |
fd2ed4d2 MP |
151 | if (p) |
152 | return p; | |
153 | ||
154 | free_shared_memory(alloc_size); | |
155 | ||
156 | return NULL; | |
157 | } | |
158 | ||
159 | static void dm_kvfree(void *ptr, size_t alloc_size) | |
160 | { | |
161 | if (!ptr) | |
162 | return; | |
163 | ||
164 | free_shared_memory(alloc_size); | |
165 | ||
0f24b79b | 166 | kvfree(ptr); |
fd2ed4d2 MP |
167 | } |
168 | ||
169 | static void dm_stat_free(struct rcu_head *head) | |
170 | { | |
171 | int cpu; | |
172 | struct dm_stat *s = container_of(head, struct dm_stat, rcu_head); | |
173 | ||
60858318 | 174 | kfree(s->histogram_boundaries); |
fd2ed4d2 MP |
175 | kfree(s->program_id); |
176 | kfree(s->aux_data); | |
dfcfac3e MP |
177 | for_each_possible_cpu(cpu) { |
178 | dm_kvfree(s->stat_percpu[cpu][0].histogram, s->histogram_alloc_size); | |
fd2ed4d2 | 179 | dm_kvfree(s->stat_percpu[cpu], s->percpu_alloc_size); |
dfcfac3e MP |
180 | } |
181 | dm_kvfree(s->stat_shared[0].tmp.histogram, s->histogram_alloc_size); | |
fd2ed4d2 MP |
182 | dm_kvfree(s, s->shared_alloc_size); |
183 | } | |
184 | ||
185 | static int dm_stat_in_flight(struct dm_stat_shared *shared) | |
186 | { | |
187 | return atomic_read(&shared->in_flight[READ]) + | |
188 | atomic_read(&shared->in_flight[WRITE]); | |
189 | } | |
190 | ||
d3aa3e06 | 191 | int dm_stats_init(struct dm_stats *stats) |
fd2ed4d2 MP |
192 | { |
193 | int cpu; | |
194 | struct dm_stats_last_position *last; | |
195 | ||
196 | mutex_init(&stats->mutex); | |
197 | INIT_LIST_HEAD(&stats->list); | |
0cdb90f0 | 198 | stats->precise_timestamps = false; |
fd2ed4d2 | 199 | stats->last = alloc_percpu(struct dm_stats_last_position); |
d3aa3e06 JJ |
200 | if (!stats->last) |
201 | return -ENOMEM; | |
202 | ||
fd2ed4d2 MP |
203 | for_each_possible_cpu(cpu) { |
204 | last = per_cpu_ptr(stats->last, cpu); | |
205 | last->last_sector = (sector_t)ULLONG_MAX; | |
206 | last->last_rw = UINT_MAX; | |
207 | } | |
d3aa3e06 JJ |
208 | |
209 | return 0; | |
fd2ed4d2 MP |
210 | } |
211 | ||
212 | void dm_stats_cleanup(struct dm_stats *stats) | |
213 | { | |
214 | size_t ni; | |
215 | struct dm_stat *s; | |
216 | struct dm_stat_shared *shared; | |
217 | ||
218 | while (!list_empty(&stats->list)) { | |
219 | s = container_of(stats->list.next, struct dm_stat, list_entry); | |
220 | list_del(&s->list_entry); | |
221 | for (ni = 0; ni < s->n_entries; ni++) { | |
222 | shared = &s->stat_shared[ni]; | |
223 | if (WARN_ON(dm_stat_in_flight(shared))) { | |
224 | DMCRIT("leaked in-flight counter at index %lu " | |
225 | "(start %llu, end %llu, step %llu): reads %d, writes %d", | |
226 | (unsigned long)ni, | |
227 | (unsigned long long)s->start, | |
228 | (unsigned long long)s->end, | |
229 | (unsigned long long)s->step, | |
230 | atomic_read(&shared->in_flight[READ]), | |
231 | atomic_read(&shared->in_flight[WRITE])); | |
232 | } | |
bfe2b014 | 233 | cond_resched(); |
fd2ed4d2 MP |
234 | } |
235 | dm_stat_free(&s->rcu_head); | |
236 | } | |
237 | free_percpu(stats->last); | |
d5ffebdd | 238 | mutex_destroy(&stats->mutex); |
fd2ed4d2 MP |
239 | } |
240 | ||
0cdb90f0 MS |
241 | static void dm_stats_recalc_precise_timestamps(struct dm_stats *stats) |
242 | { | |
243 | struct list_head *l; | |
244 | struct dm_stat *tmp_s; | |
245 | bool precise_timestamps = false; | |
246 | ||
247 | list_for_each(l, &stats->list) { | |
248 | tmp_s = container_of(l, struct dm_stat, list_entry); | |
249 | if (tmp_s->stat_flags & STAT_PRECISE_TIMESTAMPS) { | |
250 | precise_timestamps = true; | |
251 | break; | |
252 | } | |
253 | } | |
254 | stats->precise_timestamps = precise_timestamps; | |
255 | } | |
256 | ||
fd2ed4d2 | 257 | static int dm_stats_create(struct dm_stats *stats, sector_t start, sector_t end, |
86a3238c HM |
258 | sector_t step, unsigned int stat_flags, |
259 | unsigned int n_histogram_entries, | |
dfcfac3e | 260 | unsigned long long *histogram_boundaries, |
c96aec34 | 261 | const char *program_id, const char *aux_data, |
fd2ed4d2 MP |
262 | void (*suspend_callback)(struct mapped_device *), |
263 | void (*resume_callback)(struct mapped_device *), | |
264 | struct mapped_device *md) | |
265 | { | |
266 | struct list_head *l; | |
267 | struct dm_stat *s, *tmp_s; | |
268 | sector_t n_entries; | |
269 | size_t ni; | |
270 | size_t shared_alloc_size; | |
271 | size_t percpu_alloc_size; | |
dfcfac3e | 272 | size_t histogram_alloc_size; |
fd2ed4d2 MP |
273 | struct dm_stat_percpu *p; |
274 | int cpu; | |
275 | int ret_id; | |
276 | int r; | |
277 | ||
278 | if (end < start || !step) | |
279 | return -EINVAL; | |
280 | ||
281 | n_entries = end - start; | |
282 | if (dm_sector_div64(n_entries, step)) | |
283 | n_entries++; | |
284 | ||
285 | if (n_entries != (size_t)n_entries || !(size_t)(n_entries + 1)) | |
286 | return -EOVERFLOW; | |
287 | ||
fb16c799 | 288 | shared_alloc_size = struct_size(s, stat_shared, n_entries); |
fd2ed4d2 MP |
289 | if ((shared_alloc_size - sizeof(struct dm_stat)) / sizeof(struct dm_stat_shared) != n_entries) |
290 | return -EOVERFLOW; | |
291 | ||
292 | percpu_alloc_size = (size_t)n_entries * sizeof(struct dm_stat_percpu); | |
293 | if (percpu_alloc_size / sizeof(struct dm_stat_percpu) != n_entries) | |
294 | return -EOVERFLOW; | |
295 | ||
dfcfac3e MP |
296 | histogram_alloc_size = (n_histogram_entries + 1) * (size_t)n_entries * sizeof(unsigned long long); |
297 | if (histogram_alloc_size / (n_histogram_entries + 1) != (size_t)n_entries * sizeof(unsigned long long)) | |
298 | return -EOVERFLOW; | |
299 | ||
300 | if (!check_shared_memory(shared_alloc_size + histogram_alloc_size + | |
301 | num_possible_cpus() * (percpu_alloc_size + histogram_alloc_size))) | |
fd2ed4d2 MP |
302 | return -ENOMEM; |
303 | ||
304 | s = dm_kvzalloc(shared_alloc_size, NUMA_NO_NODE); | |
305 | if (!s) | |
306 | return -ENOMEM; | |
307 | ||
c96aec34 | 308 | s->stat_flags = stat_flags; |
fd2ed4d2 MP |
309 | s->n_entries = n_entries; |
310 | s->start = start; | |
311 | s->end = end; | |
312 | s->step = step; | |
313 | s->shared_alloc_size = shared_alloc_size; | |
314 | s->percpu_alloc_size = percpu_alloc_size; | |
dfcfac3e MP |
315 | s->histogram_alloc_size = histogram_alloc_size; |
316 | ||
317 | s->n_histogram_entries = n_histogram_entries; | |
318 | s->histogram_boundaries = kmemdup(histogram_boundaries, | |
319 | s->n_histogram_entries * sizeof(unsigned long long), GFP_KERNEL); | |
320 | if (!s->histogram_boundaries) { | |
321 | r = -ENOMEM; | |
322 | goto out; | |
323 | } | |
fd2ed4d2 MP |
324 | |
325 | s->program_id = kstrdup(program_id, GFP_KERNEL); | |
326 | if (!s->program_id) { | |
327 | r = -ENOMEM; | |
328 | goto out; | |
329 | } | |
330 | s->aux_data = kstrdup(aux_data, GFP_KERNEL); | |
331 | if (!s->aux_data) { | |
332 | r = -ENOMEM; | |
333 | goto out; | |
334 | } | |
335 | ||
336 | for (ni = 0; ni < n_entries; ni++) { | |
337 | atomic_set(&s->stat_shared[ni].in_flight[READ], 0); | |
338 | atomic_set(&s->stat_shared[ni].in_flight[WRITE], 0); | |
bfe2b014 | 339 | cond_resched(); |
fd2ed4d2 MP |
340 | } |
341 | ||
dfcfac3e MP |
342 | if (s->n_histogram_entries) { |
343 | unsigned long long *hi; | |
0ef0b471 | 344 | |
dfcfac3e MP |
345 | hi = dm_kvzalloc(s->histogram_alloc_size, NUMA_NO_NODE); |
346 | if (!hi) { | |
347 | r = -ENOMEM; | |
348 | goto out; | |
349 | } | |
350 | for (ni = 0; ni < n_entries; ni++) { | |
351 | s->stat_shared[ni].tmp.histogram = hi; | |
352 | hi += s->n_histogram_entries + 1; | |
bfe2b014 | 353 | cond_resched(); |
dfcfac3e MP |
354 | } |
355 | } | |
356 | ||
fd2ed4d2 MP |
357 | for_each_possible_cpu(cpu) { |
358 | p = dm_kvzalloc(percpu_alloc_size, cpu_to_node(cpu)); | |
359 | if (!p) { | |
360 | r = -ENOMEM; | |
361 | goto out; | |
362 | } | |
363 | s->stat_percpu[cpu] = p; | |
dfcfac3e MP |
364 | if (s->n_histogram_entries) { |
365 | unsigned long long *hi; | |
0ef0b471 | 366 | |
dfcfac3e MP |
367 | hi = dm_kvzalloc(s->histogram_alloc_size, cpu_to_node(cpu)); |
368 | if (!hi) { | |
369 | r = -ENOMEM; | |
370 | goto out; | |
371 | } | |
372 | for (ni = 0; ni < n_entries; ni++) { | |
373 | p[ni].histogram = hi; | |
374 | hi += s->n_histogram_entries + 1; | |
bfe2b014 | 375 | cond_resched(); |
dfcfac3e MP |
376 | } |
377 | } | |
fd2ed4d2 MP |
378 | } |
379 | ||
380 | /* | |
381 | * Suspend/resume to make sure there is no i/o in flight, | |
382 | * so that newly created statistics will be exact. | |
383 | * | |
384 | * (note: we couldn't suspend earlier because we must not | |
385 | * allocate memory while suspended) | |
386 | */ | |
387 | suspend_callback(md); | |
388 | ||
389 | mutex_lock(&stats->mutex); | |
390 | s->id = 0; | |
391 | list_for_each(l, &stats->list) { | |
392 | tmp_s = container_of(l, struct dm_stat, list_entry); | |
393 | if (WARN_ON(tmp_s->id < s->id)) { | |
394 | r = -EINVAL; | |
395 | goto out_unlock_resume; | |
396 | } | |
397 | if (tmp_s->id > s->id) | |
398 | break; | |
399 | if (unlikely(s->id == INT_MAX)) { | |
400 | r = -ENFILE; | |
401 | goto out_unlock_resume; | |
402 | } | |
403 | s->id++; | |
404 | } | |
405 | ret_id = s->id; | |
406 | list_add_tail_rcu(&s->list_entry, l); | |
0cdb90f0 MS |
407 | |
408 | dm_stats_recalc_precise_timestamps(stats); | |
409 | ||
442761fd MS |
410 | if (!static_key_enabled(&stats_enabled.key)) |
411 | static_branch_enable(&stats_enabled); | |
412 | ||
fd2ed4d2 MP |
413 | mutex_unlock(&stats->mutex); |
414 | ||
415 | resume_callback(md); | |
416 | ||
417 | return ret_id; | |
418 | ||
419 | out_unlock_resume: | |
420 | mutex_unlock(&stats->mutex); | |
421 | resume_callback(md); | |
422 | out: | |
423 | dm_stat_free(&s->rcu_head); | |
424 | return r; | |
425 | } | |
426 | ||
427 | static struct dm_stat *__dm_stats_find(struct dm_stats *stats, int id) | |
428 | { | |
429 | struct dm_stat *s; | |
430 | ||
431 | list_for_each_entry(s, &stats->list, list_entry) { | |
432 | if (s->id > id) | |
433 | break; | |
434 | if (s->id == id) | |
435 | return s; | |
436 | } | |
437 | ||
438 | return NULL; | |
439 | } | |
440 | ||
441 | static int dm_stats_delete(struct dm_stats *stats, int id) | |
442 | { | |
443 | struct dm_stat *s; | |
444 | int cpu; | |
445 | ||
446 | mutex_lock(&stats->mutex); | |
447 | ||
448 | s = __dm_stats_find(stats, id); | |
449 | if (!s) { | |
450 | mutex_unlock(&stats->mutex); | |
451 | return -ENOENT; | |
452 | } | |
453 | ||
454 | list_del_rcu(&s->list_entry); | |
0cdb90f0 MS |
455 | |
456 | dm_stats_recalc_precise_timestamps(stats); | |
457 | ||
fd2ed4d2 MP |
458 | mutex_unlock(&stats->mutex); |
459 | ||
460 | /* | |
461 | * vfree can't be called from RCU callback | |
462 | */ | |
463 | for_each_possible_cpu(cpu) | |
dfcfac3e MP |
464 | if (is_vmalloc_addr(s->stat_percpu) || |
465 | is_vmalloc_addr(s->stat_percpu[cpu][0].histogram)) | |
fd2ed4d2 | 466 | goto do_sync_free; |
dfcfac3e MP |
467 | if (is_vmalloc_addr(s) || |
468 | is_vmalloc_addr(s->stat_shared[0].tmp.histogram)) { | |
fd2ed4d2 MP |
469 | do_sync_free: |
470 | synchronize_rcu_expedited(); | |
471 | dm_stat_free(&s->rcu_head); | |
472 | } else { | |
6aa7de05 | 473 | WRITE_ONCE(dm_stat_need_rcu_barrier, 1); |
fd2ed4d2 MP |
474 | call_rcu(&s->rcu_head, dm_stat_free); |
475 | } | |
476 | return 0; | |
477 | } | |
478 | ||
479 | static int dm_stats_list(struct dm_stats *stats, const char *program, | |
86a3238c | 480 | char *result, unsigned int maxlen) |
fd2ed4d2 MP |
481 | { |
482 | struct dm_stat *s; | |
483 | sector_t len; | |
86a3238c | 484 | unsigned int sz = 0; |
fd2ed4d2 MP |
485 | |
486 | /* | |
487 | * Output format: | |
488 | * <region_id>: <start_sector>+<length> <step> <program_id> <aux_data> | |
489 | */ | |
490 | ||
491 | mutex_lock(&stats->mutex); | |
492 | list_for_each_entry(s, &stats->list, list_entry) { | |
493 | if (!program || !strcmp(program, s->program_id)) { | |
494 | len = s->end - s->start; | |
bd49784f | 495 | DMEMIT("%d: %llu+%llu %llu %s %s", s->id, |
fd2ed4d2 MP |
496 | (unsigned long long)s->start, |
497 | (unsigned long long)len, | |
498 | (unsigned long long)s->step, | |
499 | s->program_id, | |
500 | s->aux_data); | |
bd49784f MP |
501 | if (s->stat_flags & STAT_PRECISE_TIMESTAMPS) |
502 | DMEMIT(" precise_timestamps"); | |
503 | if (s->n_histogram_entries) { | |
86a3238c | 504 | unsigned int i; |
0ef0b471 | 505 | |
bd49784f MP |
506 | DMEMIT(" histogram:"); |
507 | for (i = 0; i < s->n_histogram_entries; i++) { | |
508 | if (i) | |
509 | DMEMIT(","); | |
510 | DMEMIT("%llu", s->histogram_boundaries[i]); | |
511 | } | |
512 | } | |
513 | DMEMIT("\n"); | |
fd2ed4d2 | 514 | } |
bfe2b014 | 515 | cond_resched(); |
fd2ed4d2 MP |
516 | } |
517 | mutex_unlock(&stats->mutex); | |
518 | ||
519 | return 1; | |
520 | } | |
521 | ||
c96aec34 MP |
522 | static void dm_stat_round(struct dm_stat *s, struct dm_stat_shared *shared, |
523 | struct dm_stat_percpu *p) | |
fd2ed4d2 MP |
524 | { |
525 | /* | |
526 | * This is racy, but so is part_round_stats_single. | |
527 | */ | |
c96aec34 | 528 | unsigned long long now, difference; |
86a3238c | 529 | unsigned int in_flight_read, in_flight_write; |
c96aec34 MP |
530 | |
531 | if (likely(!(s->stat_flags & STAT_PRECISE_TIMESTAMPS))) | |
532 | now = jiffies; | |
533 | else | |
534 | now = ktime_to_ns(ktime_get()); | |
fd2ed4d2 | 535 | |
c96aec34 | 536 | difference = now - shared->stamp; |
fd2ed4d2 MP |
537 | if (!difference) |
538 | return; | |
c96aec34 | 539 | |
86a3238c HM |
540 | in_flight_read = (unsigned int)atomic_read(&shared->in_flight[READ]); |
541 | in_flight_write = (unsigned int)atomic_read(&shared->in_flight[WRITE]); | |
fd2ed4d2 MP |
542 | if (in_flight_read) |
543 | p->io_ticks[READ] += difference; | |
544 | if (in_flight_write) | |
545 | p->io_ticks[WRITE] += difference; | |
546 | if (in_flight_read + in_flight_write) { | |
547 | p->io_ticks_total += difference; | |
548 | p->time_in_queue += (in_flight_read + in_flight_write) * difference; | |
549 | } | |
550 | shared->stamp = now; | |
551 | } | |
552 | ||
553 | static void dm_stat_for_entry(struct dm_stat *s, size_t entry, | |
528ec5ab | 554 | int idx, sector_t len, |
c96aec34 MP |
555 | struct dm_stats_aux *stats_aux, bool end, |
556 | unsigned long duration_jiffies) | |
fd2ed4d2 | 557 | { |
fd2ed4d2 MP |
558 | struct dm_stat_shared *shared = &s->stat_shared[entry]; |
559 | struct dm_stat_percpu *p; | |
560 | ||
561 | /* | |
bbf3f8cb | 562 | * For strict correctness we should use local_irq_save/restore |
fd2ed4d2 MP |
563 | * instead of preempt_disable/enable. |
564 | * | |
bbf3f8cb MP |
565 | * preempt_disable/enable is racy if the driver finishes bios |
566 | * from non-interrupt context as well as from interrupt context | |
567 | * or from more different interrupts. | |
fd2ed4d2 | 568 | * |
bbf3f8cb MP |
569 | * On 64-bit architectures the race only results in not counting some |
570 | * events, so it is acceptable. On 32-bit architectures the race could | |
571 | * cause the counter going off by 2^32, so we need to do proper locking | |
572 | * there. | |
fd2ed4d2 MP |
573 | * |
574 | * part_stat_lock()/part_stat_unlock() have this race too. | |
575 | */ | |
bbf3f8cb MP |
576 | #if BITS_PER_LONG == 32 |
577 | unsigned long flags; | |
0ef0b471 | 578 | |
bbf3f8cb MP |
579 | local_irq_save(flags); |
580 | #else | |
fd2ed4d2 | 581 | preempt_disable(); |
bbf3f8cb | 582 | #endif |
fd2ed4d2 MP |
583 | p = &s->stat_percpu[smp_processor_id()][entry]; |
584 | ||
585 | if (!end) { | |
c96aec34 | 586 | dm_stat_round(s, shared, p); |
fd2ed4d2 MP |
587 | atomic_inc(&shared->in_flight[idx]); |
588 | } else { | |
dfcfac3e | 589 | unsigned long long duration; |
0ef0b471 | 590 | |
c96aec34 | 591 | dm_stat_round(s, shared, p); |
fd2ed4d2 MP |
592 | atomic_dec(&shared->in_flight[idx]); |
593 | p->sectors[idx] += len; | |
594 | p->ios[idx] += 1; | |
c96aec34 | 595 | p->merges[idx] += stats_aux->merged; |
dfcfac3e | 596 | if (!(s->stat_flags & STAT_PRECISE_TIMESTAMPS)) { |
c96aec34 | 597 | p->ticks[idx] += duration_jiffies; |
dfcfac3e MP |
598 | duration = jiffies_to_msecs(duration_jiffies); |
599 | } else { | |
c96aec34 | 600 | p->ticks[idx] += stats_aux->duration_ns; |
dfcfac3e MP |
601 | duration = stats_aux->duration_ns; |
602 | } | |
603 | if (s->n_histogram_entries) { | |
86a3238c | 604 | unsigned int lo = 0, hi = s->n_histogram_entries + 1; |
0ef0b471 | 605 | |
dfcfac3e | 606 | while (lo + 1 < hi) { |
86a3238c | 607 | unsigned int mid = (lo + hi) / 2; |
0ef0b471 | 608 | |
2d0f25cb | 609 | if (s->histogram_boundaries[mid - 1] > duration) |
dfcfac3e | 610 | hi = mid; |
2d0f25cb | 611 | else |
dfcfac3e | 612 | lo = mid; |
dfcfac3e MP |
613 | } |
614 | p->histogram[lo]++; | |
615 | } | |
fd2ed4d2 MP |
616 | } |
617 | ||
bbf3f8cb MP |
618 | #if BITS_PER_LONG == 32 |
619 | local_irq_restore(flags); | |
620 | #else | |
fd2ed4d2 | 621 | preempt_enable(); |
bbf3f8cb | 622 | #endif |
fd2ed4d2 MP |
623 | } |
624 | ||
528ec5ab | 625 | static void __dm_stat_bio(struct dm_stat *s, int bi_rw, |
fd2ed4d2 | 626 | sector_t bi_sector, sector_t end_sector, |
c96aec34 | 627 | bool end, unsigned long duration_jiffies, |
fd2ed4d2 MP |
628 | struct dm_stats_aux *stats_aux) |
629 | { | |
630 | sector_t rel_sector, offset, todo, fragment_len; | |
631 | size_t entry; | |
632 | ||
633 | if (end_sector <= s->start || bi_sector >= s->end) | |
634 | return; | |
635 | if (unlikely(bi_sector < s->start)) { | |
636 | rel_sector = 0; | |
637 | todo = end_sector - s->start; | |
638 | } else { | |
639 | rel_sector = bi_sector - s->start; | |
640 | todo = end_sector - bi_sector; | |
641 | } | |
642 | if (unlikely(end_sector > s->end)) | |
643 | todo -= (end_sector - s->end); | |
644 | ||
645 | offset = dm_sector_div64(rel_sector, s->step); | |
646 | entry = rel_sector; | |
647 | do { | |
648 | if (WARN_ON_ONCE(entry >= s->n_entries)) { | |
649 | DMCRIT("Invalid area access in region id %d", s->id); | |
650 | return; | |
651 | } | |
652 | fragment_len = todo; | |
653 | if (fragment_len > s->step - offset) | |
654 | fragment_len = s->step - offset; | |
655 | dm_stat_for_entry(s, entry, bi_rw, fragment_len, | |
c96aec34 | 656 | stats_aux, end, duration_jiffies); |
fd2ed4d2 MP |
657 | todo -= fragment_len; |
658 | entry++; | |
659 | offset = 0; | |
660 | } while (unlikely(todo != 0)); | |
661 | } | |
662 | ||
663 | void dm_stats_account_io(struct dm_stats *stats, unsigned long bi_rw, | |
86a3238c | 664 | sector_t bi_sector, unsigned int bi_sectors, bool end, |
8d394bc4 | 665 | unsigned long start_time, |
c96aec34 | 666 | struct dm_stats_aux *stats_aux) |
fd2ed4d2 MP |
667 | { |
668 | struct dm_stat *s; | |
669 | sector_t end_sector; | |
670 | struct dm_stats_last_position *last; | |
c96aec34 | 671 | bool got_precise_time; |
8d394bc4 | 672 | unsigned long duration_jiffies = 0; |
fd2ed4d2 MP |
673 | |
674 | if (unlikely(!bi_sectors)) | |
675 | return; | |
676 | ||
677 | end_sector = bi_sector + bi_sectors; | |
678 | ||
679 | if (!end) { | |
680 | /* | |
681 | * A race condition can at worst result in the merged flag being | |
682 | * misrepresented, so we don't have to disable preemption here. | |
683 | */ | |
1f125e76 | 684 | last = raw_cpu_ptr(stats->last); |
fd2ed4d2 | 685 | stats_aux->merged = |
6aa7de05 | 686 | (bi_sector == (READ_ONCE(last->last_sector) && |
528ec5ab | 687 | ((bi_rw == WRITE) == |
6aa7de05 | 688 | (READ_ONCE(last->last_rw) == WRITE)) |
fd2ed4d2 | 689 | )); |
6aa7de05 MR |
690 | WRITE_ONCE(last->last_sector, end_sector); |
691 | WRITE_ONCE(last->last_rw, bi_rw); | |
8d394bc4 MS |
692 | } else |
693 | duration_jiffies = jiffies - start_time; | |
fd2ed4d2 MP |
694 | |
695 | rcu_read_lock(); | |
696 | ||
c96aec34 MP |
697 | got_precise_time = false; |
698 | list_for_each_entry_rcu(s, &stats->list, list_entry) { | |
699 | if (s->stat_flags & STAT_PRECISE_TIMESTAMPS && !got_precise_time) { | |
0cdb90f0 MS |
700 | /* start (!end) duration_ns is set by DM core's alloc_io() */ |
701 | if (end) | |
c96aec34 MP |
702 | stats_aux->duration_ns = ktime_to_ns(ktime_get()) - stats_aux->duration_ns; |
703 | got_precise_time = true; | |
704 | } | |
705 | __dm_stat_bio(s, bi_rw, bi_sector, end_sector, end, duration_jiffies, stats_aux); | |
706 | } | |
fd2ed4d2 MP |
707 | |
708 | rcu_read_unlock(); | |
709 | } | |
710 | ||
711 | static void __dm_stat_init_temporary_percpu_totals(struct dm_stat_shared *shared, | |
712 | struct dm_stat *s, size_t x) | |
713 | { | |
714 | int cpu; | |
715 | struct dm_stat_percpu *p; | |
716 | ||
717 | local_irq_disable(); | |
718 | p = &s->stat_percpu[smp_processor_id()][x]; | |
c96aec34 | 719 | dm_stat_round(s, shared, p); |
fd2ed4d2 MP |
720 | local_irq_enable(); |
721 | ||
dfcfac3e MP |
722 | shared->tmp.sectors[READ] = 0; |
723 | shared->tmp.sectors[WRITE] = 0; | |
724 | shared->tmp.ios[READ] = 0; | |
725 | shared->tmp.ios[WRITE] = 0; | |
726 | shared->tmp.merges[READ] = 0; | |
727 | shared->tmp.merges[WRITE] = 0; | |
728 | shared->tmp.ticks[READ] = 0; | |
729 | shared->tmp.ticks[WRITE] = 0; | |
730 | shared->tmp.io_ticks[READ] = 0; | |
731 | shared->tmp.io_ticks[WRITE] = 0; | |
732 | shared->tmp.io_ticks_total = 0; | |
733 | shared->tmp.time_in_queue = 0; | |
734 | ||
735 | if (s->n_histogram_entries) | |
736 | memset(shared->tmp.histogram, 0, (s->n_histogram_entries + 1) * sizeof(unsigned long long)); | |
737 | ||
fd2ed4d2 MP |
738 | for_each_possible_cpu(cpu) { |
739 | p = &s->stat_percpu[cpu][x]; | |
6aa7de05 MR |
740 | shared->tmp.sectors[READ] += READ_ONCE(p->sectors[READ]); |
741 | shared->tmp.sectors[WRITE] += READ_ONCE(p->sectors[WRITE]); | |
742 | shared->tmp.ios[READ] += READ_ONCE(p->ios[READ]); | |
743 | shared->tmp.ios[WRITE] += READ_ONCE(p->ios[WRITE]); | |
744 | shared->tmp.merges[READ] += READ_ONCE(p->merges[READ]); | |
745 | shared->tmp.merges[WRITE] += READ_ONCE(p->merges[WRITE]); | |
746 | shared->tmp.ticks[READ] += READ_ONCE(p->ticks[READ]); | |
747 | shared->tmp.ticks[WRITE] += READ_ONCE(p->ticks[WRITE]); | |
748 | shared->tmp.io_ticks[READ] += READ_ONCE(p->io_ticks[READ]); | |
749 | shared->tmp.io_ticks[WRITE] += READ_ONCE(p->io_ticks[WRITE]); | |
750 | shared->tmp.io_ticks_total += READ_ONCE(p->io_ticks_total); | |
751 | shared->tmp.time_in_queue += READ_ONCE(p->time_in_queue); | |
dfcfac3e | 752 | if (s->n_histogram_entries) { |
86a3238c | 753 | unsigned int i; |
0ef0b471 | 754 | |
dfcfac3e | 755 | for (i = 0; i < s->n_histogram_entries + 1; i++) |
6aa7de05 | 756 | shared->tmp.histogram[i] += READ_ONCE(p->histogram[i]); |
dfcfac3e | 757 | } |
fd2ed4d2 MP |
758 | } |
759 | } | |
760 | ||
761 | static void __dm_stat_clear(struct dm_stat *s, size_t idx_start, size_t idx_end, | |
762 | bool init_tmp_percpu_totals) | |
763 | { | |
764 | size_t x; | |
765 | struct dm_stat_shared *shared; | |
766 | struct dm_stat_percpu *p; | |
767 | ||
768 | for (x = idx_start; x < idx_end; x++) { | |
769 | shared = &s->stat_shared[x]; | |
770 | if (init_tmp_percpu_totals) | |
771 | __dm_stat_init_temporary_percpu_totals(shared, s, x); | |
772 | local_irq_disable(); | |
773 | p = &s->stat_percpu[smp_processor_id()][x]; | |
774 | p->sectors[READ] -= shared->tmp.sectors[READ]; | |
775 | p->sectors[WRITE] -= shared->tmp.sectors[WRITE]; | |
776 | p->ios[READ] -= shared->tmp.ios[READ]; | |
777 | p->ios[WRITE] -= shared->tmp.ios[WRITE]; | |
778 | p->merges[READ] -= shared->tmp.merges[READ]; | |
779 | p->merges[WRITE] -= shared->tmp.merges[WRITE]; | |
780 | p->ticks[READ] -= shared->tmp.ticks[READ]; | |
781 | p->ticks[WRITE] -= shared->tmp.ticks[WRITE]; | |
782 | p->io_ticks[READ] -= shared->tmp.io_ticks[READ]; | |
783 | p->io_ticks[WRITE] -= shared->tmp.io_ticks[WRITE]; | |
784 | p->io_ticks_total -= shared->tmp.io_ticks_total; | |
785 | p->time_in_queue -= shared->tmp.time_in_queue; | |
786 | local_irq_enable(); | |
dfcfac3e | 787 | if (s->n_histogram_entries) { |
86a3238c | 788 | unsigned int i; |
0ef0b471 | 789 | |
dfcfac3e MP |
790 | for (i = 0; i < s->n_histogram_entries + 1; i++) { |
791 | local_irq_disable(); | |
792 | p = &s->stat_percpu[smp_processor_id()][x]; | |
793 | p->histogram[i] -= shared->tmp.histogram[i]; | |
794 | local_irq_enable(); | |
795 | } | |
796 | } | |
bfe2b014 | 797 | cond_resched(); |
fd2ed4d2 MP |
798 | } |
799 | } | |
800 | ||
801 | static int dm_stats_clear(struct dm_stats *stats, int id) | |
802 | { | |
803 | struct dm_stat *s; | |
804 | ||
805 | mutex_lock(&stats->mutex); | |
806 | ||
807 | s = __dm_stats_find(stats, id); | |
808 | if (!s) { | |
809 | mutex_unlock(&stats->mutex); | |
810 | return -ENOENT; | |
811 | } | |
812 | ||
813 | __dm_stat_clear(s, 0, s->n_entries, true); | |
814 | ||
815 | mutex_unlock(&stats->mutex); | |
816 | ||
817 | return 1; | |
818 | } | |
819 | ||
820 | /* | |
821 | * This is like jiffies_to_msec, but works for 64-bit values. | |
822 | */ | |
c96aec34 | 823 | static unsigned long long dm_jiffies_to_msec64(struct dm_stat *s, unsigned long long j) |
fd2ed4d2 | 824 | { |
c96aec34 | 825 | unsigned long long result; |
86a3238c | 826 | unsigned int mult; |
fd2ed4d2 | 827 | |
c96aec34 MP |
828 | if (s->stat_flags & STAT_PRECISE_TIMESTAMPS) |
829 | return j; | |
830 | ||
831 | result = 0; | |
fd2ed4d2 MP |
832 | if (j) |
833 | result = jiffies_to_msecs(j & 0x3fffff); | |
834 | if (j >= 1 << 22) { | |
835 | mult = jiffies_to_msecs(1 << 22); | |
836 | result += (unsigned long long)mult * (unsigned long long)jiffies_to_msecs((j >> 22) & 0x3fffff); | |
837 | } | |
838 | if (j >= 1ULL << 44) | |
839 | result += (unsigned long long)mult * (unsigned long long)mult * (unsigned long long)jiffies_to_msecs(j >> 44); | |
840 | ||
841 | return result; | |
842 | } | |
843 | ||
844 | static int dm_stats_print(struct dm_stats *stats, int id, | |
845 | size_t idx_start, size_t idx_len, | |
86a3238c | 846 | bool clear, char *result, unsigned int maxlen) |
fd2ed4d2 | 847 | { |
86a3238c | 848 | unsigned int sz = 0; |
fd2ed4d2 MP |
849 | struct dm_stat *s; |
850 | size_t x; | |
851 | sector_t start, end, step; | |
852 | size_t idx_end; | |
853 | struct dm_stat_shared *shared; | |
854 | ||
855 | /* | |
856 | * Output format: | |
857 | * <start_sector>+<length> counters | |
858 | */ | |
859 | ||
860 | mutex_lock(&stats->mutex); | |
861 | ||
862 | s = __dm_stats_find(stats, id); | |
863 | if (!s) { | |
864 | mutex_unlock(&stats->mutex); | |
865 | return -ENOENT; | |
866 | } | |
867 | ||
868 | idx_end = idx_start + idx_len; | |
869 | if (idx_end < idx_start || | |
870 | idx_end > s->n_entries) | |
871 | idx_end = s->n_entries; | |
872 | ||
873 | if (idx_start > idx_end) | |
874 | idx_start = idx_end; | |
875 | ||
876 | step = s->step; | |
877 | start = s->start + (step * idx_start); | |
878 | ||
879 | for (x = idx_start; x < idx_end; x++, start = end) { | |
880 | shared = &s->stat_shared[x]; | |
881 | end = start + step; | |
882 | if (unlikely(end > s->end)) | |
883 | end = s->end; | |
884 | ||
885 | __dm_stat_init_temporary_percpu_totals(shared, s, x); | |
886 | ||
dfcfac3e | 887 | DMEMIT("%llu+%llu %llu %llu %llu %llu %llu %llu %llu %llu %d %llu %llu %llu %llu", |
fd2ed4d2 MP |
888 | (unsigned long long)start, |
889 | (unsigned long long)step, | |
890 | shared->tmp.ios[READ], | |
891 | shared->tmp.merges[READ], | |
892 | shared->tmp.sectors[READ], | |
c96aec34 | 893 | dm_jiffies_to_msec64(s, shared->tmp.ticks[READ]), |
fd2ed4d2 MP |
894 | shared->tmp.ios[WRITE], |
895 | shared->tmp.merges[WRITE], | |
896 | shared->tmp.sectors[WRITE], | |
c96aec34 | 897 | dm_jiffies_to_msec64(s, shared->tmp.ticks[WRITE]), |
fd2ed4d2 | 898 | dm_stat_in_flight(shared), |
c96aec34 MP |
899 | dm_jiffies_to_msec64(s, shared->tmp.io_ticks_total), |
900 | dm_jiffies_to_msec64(s, shared->tmp.time_in_queue), | |
901 | dm_jiffies_to_msec64(s, shared->tmp.io_ticks[READ]), | |
902 | dm_jiffies_to_msec64(s, shared->tmp.io_ticks[WRITE])); | |
dfcfac3e | 903 | if (s->n_histogram_entries) { |
86a3238c | 904 | unsigned int i; |
0ef0b471 | 905 | |
2d0f25cb | 906 | for (i = 0; i < s->n_histogram_entries + 1; i++) |
dfcfac3e | 907 | DMEMIT("%s%llu", !i ? " " : ":", shared->tmp.histogram[i]); |
dfcfac3e MP |
908 | } |
909 | DMEMIT("\n"); | |
fd2ed4d2 MP |
910 | |
911 | if (unlikely(sz + 1 >= maxlen)) | |
912 | goto buffer_overflow; | |
bfe2b014 MP |
913 | |
914 | cond_resched(); | |
fd2ed4d2 MP |
915 | } |
916 | ||
917 | if (clear) | |
918 | __dm_stat_clear(s, idx_start, idx_end, false); | |
919 | ||
920 | buffer_overflow: | |
921 | mutex_unlock(&stats->mutex); | |
922 | ||
923 | return 1; | |
924 | } | |
925 | ||
926 | static int dm_stats_set_aux(struct dm_stats *stats, int id, const char *aux_data) | |
927 | { | |
928 | struct dm_stat *s; | |
929 | const char *new_aux_data; | |
930 | ||
931 | mutex_lock(&stats->mutex); | |
932 | ||
933 | s = __dm_stats_find(stats, id); | |
934 | if (!s) { | |
935 | mutex_unlock(&stats->mutex); | |
936 | return -ENOENT; | |
937 | } | |
938 | ||
939 | new_aux_data = kstrdup(aux_data, GFP_KERNEL); | |
940 | if (!new_aux_data) { | |
941 | mutex_unlock(&stats->mutex); | |
942 | return -ENOMEM; | |
943 | } | |
944 | ||
945 | kfree(s->aux_data); | |
946 | s->aux_data = new_aux_data; | |
947 | ||
948 | mutex_unlock(&stats->mutex); | |
949 | ||
950 | return 0; | |
951 | } | |
952 | ||
86a3238c | 953 | static int parse_histogram(const char *h, unsigned int *n_histogram_entries, |
dfcfac3e MP |
954 | unsigned long long **histogram_boundaries) |
955 | { | |
956 | const char *q; | |
86a3238c | 957 | unsigned int n; |
dfcfac3e MP |
958 | unsigned long long last; |
959 | ||
960 | *n_histogram_entries = 1; | |
961 | for (q = h; *q; q++) | |
962 | if (*q == ',') | |
963 | (*n_histogram_entries)++; | |
964 | ||
6da2ec56 KC |
965 | *histogram_boundaries = kmalloc_array(*n_histogram_entries, |
966 | sizeof(unsigned long long), | |
967 | GFP_KERNEL); | |
dfcfac3e MP |
968 | if (!*histogram_boundaries) |
969 | return -ENOMEM; | |
970 | ||
971 | n = 0; | |
972 | last = 0; | |
973 | while (1) { | |
974 | unsigned long long hi; | |
975 | int s; | |
976 | char ch; | |
0ef0b471 | 977 | |
dfcfac3e MP |
978 | s = sscanf(h, "%llu%c", &hi, &ch); |
979 | if (!s || (s == 2 && ch != ',')) | |
980 | return -EINVAL; | |
981 | if (hi <= last) | |
982 | return -EINVAL; | |
983 | last = hi; | |
984 | (*histogram_boundaries)[n] = hi; | |
985 | if (s == 1) | |
986 | return 0; | |
987 | h = strchr(h, ',') + 1; | |
988 | n++; | |
989 | } | |
990 | } | |
991 | ||
fd2ed4d2 | 992 | static int message_stats_create(struct mapped_device *md, |
86a3238c HM |
993 | unsigned int argc, char **argv, |
994 | char *result, unsigned int maxlen) | |
fd2ed4d2 | 995 | { |
dfcfac3e | 996 | int r; |
fd2ed4d2 MP |
997 | int id; |
998 | char dummy; | |
999 | unsigned long long start, end, len, step; | |
86a3238c | 1000 | unsigned int divisor; |
fd2ed4d2 | 1001 | const char *program_id, *aux_data; |
86a3238c | 1002 | unsigned int stat_flags = 0; |
86a3238c | 1003 | unsigned int n_histogram_entries = 0; |
dfcfac3e | 1004 | unsigned long long *histogram_boundaries = NULL; |
c96aec34 MP |
1005 | struct dm_arg_set as, as_backup; |
1006 | const char *a; | |
86a3238c | 1007 | unsigned int feature_args; |
fd2ed4d2 MP |
1008 | |
1009 | /* | |
1010 | * Input format: | |
c96aec34 | 1011 | * <range> <step> [<extra_parameters> <parameters>] [<program_id> [<aux_data>]] |
fd2ed4d2 MP |
1012 | */ |
1013 | ||
c96aec34 | 1014 | if (argc < 3) |
dfcfac3e | 1015 | goto ret_einval; |
fd2ed4d2 | 1016 | |
c96aec34 MP |
1017 | as.argc = argc; |
1018 | as.argv = argv; | |
1019 | dm_consume_args(&as, 1); | |
1020 | ||
1021 | a = dm_shift_arg(&as); | |
1022 | if (!strcmp(a, "-")) { | |
fd2ed4d2 MP |
1023 | start = 0; |
1024 | len = dm_get_size(md); | |
1025 | if (!len) | |
1026 | len = 1; | |
c96aec34 | 1027 | } else if (sscanf(a, "%llu+%llu%c", &start, &len, &dummy) != 2 || |
fd2ed4d2 | 1028 | start != (sector_t)start || len != (sector_t)len) |
dfcfac3e | 1029 | goto ret_einval; |
fd2ed4d2 MP |
1030 | |
1031 | end = start + len; | |
1032 | if (start >= end) | |
dfcfac3e | 1033 | goto ret_einval; |
fd2ed4d2 | 1034 | |
c96aec34 MP |
1035 | a = dm_shift_arg(&as); |
1036 | if (sscanf(a, "/%u%c", &divisor, &dummy) == 1) { | |
dd4c1b7d MP |
1037 | if (!divisor) |
1038 | return -EINVAL; | |
fd2ed4d2 MP |
1039 | step = end - start; |
1040 | if (do_div(step, divisor)) | |
1041 | step++; | |
1042 | if (!step) | |
1043 | step = 1; | |
c96aec34 | 1044 | } else if (sscanf(a, "%llu%c", &step, &dummy) != 1 || |
fd2ed4d2 | 1045 | step != (sector_t)step || !step) |
dfcfac3e | 1046 | goto ret_einval; |
fd2ed4d2 | 1047 | |
c96aec34 MP |
1048 | as_backup = as; |
1049 | a = dm_shift_arg(&as); | |
1050 | if (a && sscanf(a, "%u%c", &feature_args, &dummy) == 1) { | |
1051 | while (feature_args--) { | |
1052 | a = dm_shift_arg(&as); | |
1053 | if (!a) | |
dfcfac3e | 1054 | goto ret_einval; |
c96aec34 MP |
1055 | if (!strcasecmp(a, "precise_timestamps")) |
1056 | stat_flags |= STAT_PRECISE_TIMESTAMPS; | |
dfcfac3e MP |
1057 | else if (!strncasecmp(a, "histogram:", 10)) { |
1058 | if (n_histogram_entries) | |
1059 | goto ret_einval; | |
d715fa23 HM |
1060 | r = parse_histogram(a + 10, &n_histogram_entries, &histogram_boundaries); |
1061 | if (r) | |
dfcfac3e MP |
1062 | goto ret; |
1063 | } else | |
1064 | goto ret_einval; | |
c96aec34 MP |
1065 | } |
1066 | } else { | |
1067 | as = as_backup; | |
1068 | } | |
1069 | ||
fd2ed4d2 MP |
1070 | program_id = "-"; |
1071 | aux_data = "-"; | |
1072 | ||
c96aec34 MP |
1073 | a = dm_shift_arg(&as); |
1074 | if (a) | |
1075 | program_id = a; | |
1076 | ||
1077 | a = dm_shift_arg(&as); | |
1078 | if (a) | |
1079 | aux_data = a; | |
fd2ed4d2 | 1080 | |
c96aec34 | 1081 | if (as.argc) |
dfcfac3e | 1082 | goto ret_einval; |
fd2ed4d2 MP |
1083 | |
1084 | /* | |
1085 | * If a buffer overflow happens after we created the region, | |
1086 | * it's too late (the userspace would retry with a larger | |
1087 | * buffer, but the region id that caused the overflow is already | |
1088 | * leaked). So we must detect buffer overflow in advance. | |
1089 | */ | |
1090 | snprintf(result, maxlen, "%d", INT_MAX); | |
dfcfac3e MP |
1091 | if (dm_message_test_buffer_overflow(result, maxlen)) { |
1092 | r = 1; | |
1093 | goto ret; | |
1094 | } | |
fd2ed4d2 | 1095 | |
dfcfac3e MP |
1096 | id = dm_stats_create(dm_get_stats(md), start, end, step, stat_flags, |
1097 | n_histogram_entries, histogram_boundaries, program_id, aux_data, | |
ffcc3936 | 1098 | dm_internal_suspend_fast, dm_internal_resume_fast, md); |
dfcfac3e MP |
1099 | if (id < 0) { |
1100 | r = id; | |
1101 | goto ret; | |
1102 | } | |
fd2ed4d2 MP |
1103 | |
1104 | snprintf(result, maxlen, "%d", id); | |
1105 | ||
dfcfac3e MP |
1106 | r = 1; |
1107 | goto ret; | |
1108 | ||
1109 | ret_einval: | |
1110 | r = -EINVAL; | |
1111 | ret: | |
1112 | kfree(histogram_boundaries); | |
1113 | return r; | |
fd2ed4d2 MP |
1114 | } |
1115 | ||
1116 | static int message_stats_delete(struct mapped_device *md, | |
86a3238c | 1117 | unsigned int argc, char **argv) |
fd2ed4d2 MP |
1118 | { |
1119 | int id; | |
1120 | char dummy; | |
1121 | ||
1122 | if (argc != 2) | |
1123 | return -EINVAL; | |
1124 | ||
1125 | if (sscanf(argv[1], "%d%c", &id, &dummy) != 1 || id < 0) | |
1126 | return -EINVAL; | |
1127 | ||
1128 | return dm_stats_delete(dm_get_stats(md), id); | |
1129 | } | |
1130 | ||
1131 | static int message_stats_clear(struct mapped_device *md, | |
86a3238c | 1132 | unsigned int argc, char **argv) |
fd2ed4d2 MP |
1133 | { |
1134 | int id; | |
1135 | char dummy; | |
1136 | ||
1137 | if (argc != 2) | |
1138 | return -EINVAL; | |
1139 | ||
1140 | if (sscanf(argv[1], "%d%c", &id, &dummy) != 1 || id < 0) | |
1141 | return -EINVAL; | |
1142 | ||
1143 | return dm_stats_clear(dm_get_stats(md), id); | |
1144 | } | |
1145 | ||
1146 | static int message_stats_list(struct mapped_device *md, | |
86a3238c HM |
1147 | unsigned int argc, char **argv, |
1148 | char *result, unsigned int maxlen) | |
fd2ed4d2 MP |
1149 | { |
1150 | int r; | |
1151 | const char *program = NULL; | |
1152 | ||
1153 | if (argc < 1 || argc > 2) | |
1154 | return -EINVAL; | |
1155 | ||
1156 | if (argc > 1) { | |
1157 | program = kstrdup(argv[1], GFP_KERNEL); | |
1158 | if (!program) | |
1159 | return -ENOMEM; | |
1160 | } | |
1161 | ||
1162 | r = dm_stats_list(dm_get_stats(md), program, result, maxlen); | |
1163 | ||
1164 | kfree(program); | |
1165 | ||
1166 | return r; | |
1167 | } | |
1168 | ||
1169 | static int message_stats_print(struct mapped_device *md, | |
86a3238c HM |
1170 | unsigned int argc, char **argv, bool clear, |
1171 | char *result, unsigned int maxlen) | |
fd2ed4d2 MP |
1172 | { |
1173 | int id; | |
1174 | char dummy; | |
1175 | unsigned long idx_start = 0, idx_len = ULONG_MAX; | |
1176 | ||
1177 | if (argc != 2 && argc != 4) | |
1178 | return -EINVAL; | |
1179 | ||
1180 | if (sscanf(argv[1], "%d%c", &id, &dummy) != 1 || id < 0) | |
1181 | return -EINVAL; | |
1182 | ||
1183 | if (argc > 3) { | |
1184 | if (strcmp(argv[2], "-") && | |
1185 | sscanf(argv[2], "%lu%c", &idx_start, &dummy) != 1) | |
1186 | return -EINVAL; | |
1187 | if (strcmp(argv[3], "-") && | |
1188 | sscanf(argv[3], "%lu%c", &idx_len, &dummy) != 1) | |
1189 | return -EINVAL; | |
1190 | } | |
1191 | ||
1192 | return dm_stats_print(dm_get_stats(md), id, idx_start, idx_len, clear, | |
1193 | result, maxlen); | |
1194 | } | |
1195 | ||
1196 | static int message_stats_set_aux(struct mapped_device *md, | |
86a3238c | 1197 | unsigned int argc, char **argv) |
fd2ed4d2 MP |
1198 | { |
1199 | int id; | |
1200 | char dummy; | |
1201 | ||
1202 | if (argc != 3) | |
1203 | return -EINVAL; | |
1204 | ||
1205 | if (sscanf(argv[1], "%d%c", &id, &dummy) != 1 || id < 0) | |
1206 | return -EINVAL; | |
1207 | ||
1208 | return dm_stats_set_aux(dm_get_stats(md), id, argv[2]); | |
1209 | } | |
1210 | ||
86a3238c HM |
1211 | int dm_stats_message(struct mapped_device *md, unsigned int argc, char **argv, |
1212 | char *result, unsigned int maxlen) | |
fd2ed4d2 MP |
1213 | { |
1214 | int r; | |
1215 | ||
fd2ed4d2 MP |
1216 | /* All messages here must start with '@' */ |
1217 | if (!strcasecmp(argv[0], "@stats_create")) | |
1218 | r = message_stats_create(md, argc, argv, result, maxlen); | |
1219 | else if (!strcasecmp(argv[0], "@stats_delete")) | |
1220 | r = message_stats_delete(md, argc, argv); | |
1221 | else if (!strcasecmp(argv[0], "@stats_clear")) | |
1222 | r = message_stats_clear(md, argc, argv); | |
1223 | else if (!strcasecmp(argv[0], "@stats_list")) | |
1224 | r = message_stats_list(md, argc, argv, result, maxlen); | |
1225 | else if (!strcasecmp(argv[0], "@stats_print")) | |
1226 | r = message_stats_print(md, argc, argv, false, result, maxlen); | |
1227 | else if (!strcasecmp(argv[0], "@stats_print_clear")) | |
1228 | r = message_stats_print(md, argc, argv, true, result, maxlen); | |
1229 | else if (!strcasecmp(argv[0], "@stats_set_aux")) | |
1230 | r = message_stats_set_aux(md, argc, argv); | |
1231 | else | |
1232 | return 2; /* this wasn't a stats message */ | |
1233 | ||
1234 | if (r == -EINVAL) | |
43e6c111 | 1235 | DMCRIT("Invalid parameters for message %s", argv[0]); |
fd2ed4d2 MP |
1236 | |
1237 | return r; | |
1238 | } | |
1239 | ||
1240 | int __init dm_statistics_init(void) | |
1241 | { | |
76f5bee5 | 1242 | shared_memory_amount = 0; |
fd2ed4d2 MP |
1243 | dm_stat_need_rcu_barrier = 0; |
1244 | return 0; | |
1245 | } | |
1246 | ||
1247 | void dm_statistics_exit(void) | |
1248 | { | |
1249 | if (dm_stat_need_rcu_barrier) | |
1250 | rcu_barrier(); | |
1251 | if (WARN_ON(shared_memory_amount)) | |
1252 | DMCRIT("shared_memory_amount leaked: %lu", shared_memory_amount); | |
1253 | } | |
1254 | ||
6a808034 | 1255 | module_param_named(stats_current_allocated_bytes, shared_memory_amount, ulong, 0444); |
fd2ed4d2 | 1256 | MODULE_PARM_DESC(stats_current_allocated_bytes, "Memory currently used by statistics"); |