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280c2908 JB |
1 | // SPDX-License-Identifier: GPL-2.0 |
2 | ||
784352fe | 3 | #include "misc.h" |
280c2908 JB |
4 | #include "ctree.h" |
5 | #include "space-info.h" | |
6 | #include "sysfs.h" | |
7 | #include "volumes.h" | |
5da6afeb | 8 | #include "free-space-cache.h" |
0d9764f6 JB |
9 | #include "ordered-data.h" |
10 | #include "transaction.h" | |
aac0023c | 11 | #include "block-group.h" |
280c2908 | 12 | |
4b8b0528 JB |
13 | /* |
14 | * HOW DOES SPACE RESERVATION WORK | |
15 | * | |
16 | * If you want to know about delalloc specifically, there is a separate comment | |
17 | * for that with the delalloc code. This comment is about how the whole system | |
18 | * works generally. | |
19 | * | |
20 | * BASIC CONCEPTS | |
21 | * | |
22 | * 1) space_info. This is the ultimate arbiter of how much space we can use. | |
23 | * There's a description of the bytes_ fields with the struct declaration, | |
24 | * refer to that for specifics on each field. Suffice it to say that for | |
25 | * reservations we care about total_bytes - SUM(space_info->bytes_) when | |
26 | * determining if there is space to make an allocation. There is a space_info | |
27 | * for METADATA, SYSTEM, and DATA areas. | |
28 | * | |
29 | * 2) block_rsv's. These are basically buckets for every different type of | |
30 | * metadata reservation we have. You can see the comment in the block_rsv | |
31 | * code on the rules for each type, but generally block_rsv->reserved is how | |
32 | * much space is accounted for in space_info->bytes_may_use. | |
33 | * | |
34 | * 3) btrfs_calc*_size. These are the worst case calculations we used based | |
35 | * on the number of items we will want to modify. We have one for changing | |
36 | * items, and one for inserting new items. Generally we use these helpers to | |
37 | * determine the size of the block reserves, and then use the actual bytes | |
38 | * values to adjust the space_info counters. | |
39 | * | |
40 | * MAKING RESERVATIONS, THE NORMAL CASE | |
41 | * | |
42 | * We call into either btrfs_reserve_data_bytes() or | |
43 | * btrfs_reserve_metadata_bytes(), depending on which we're looking for, with | |
44 | * num_bytes we want to reserve. | |
45 | * | |
46 | * ->reserve | |
47 | * space_info->bytes_may_reserve += num_bytes | |
48 | * | |
49 | * ->extent allocation | |
50 | * Call btrfs_add_reserved_bytes() which does | |
51 | * space_info->bytes_may_reserve -= num_bytes | |
52 | * space_info->bytes_reserved += extent_bytes | |
53 | * | |
54 | * ->insert reference | |
55 | * Call btrfs_update_block_group() which does | |
56 | * space_info->bytes_reserved -= extent_bytes | |
57 | * space_info->bytes_used += extent_bytes | |
58 | * | |
59 | * MAKING RESERVATIONS, FLUSHING NORMALLY (non-priority) | |
60 | * | |
61 | * Assume we are unable to simply make the reservation because we do not have | |
62 | * enough space | |
63 | * | |
64 | * -> __reserve_bytes | |
65 | * create a reserve_ticket with ->bytes set to our reservation, add it to | |
66 | * the tail of space_info->tickets, kick async flush thread | |
67 | * | |
68 | * ->handle_reserve_ticket | |
69 | * wait on ticket->wait for ->bytes to be reduced to 0, or ->error to be set | |
70 | * on the ticket. | |
71 | * | |
72 | * -> btrfs_async_reclaim_metadata_space/btrfs_async_reclaim_data_space | |
73 | * Flushes various things attempting to free up space. | |
74 | * | |
75 | * -> btrfs_try_granting_tickets() | |
76 | * This is called by anything that either subtracts space from | |
77 | * space_info->bytes_may_use, ->bytes_pinned, etc, or adds to the | |
78 | * space_info->total_bytes. This loops through the ->priority_tickets and | |
79 | * then the ->tickets list checking to see if the reservation can be | |
80 | * completed. If it can the space is added to space_info->bytes_may_use and | |
81 | * the ticket is woken up. | |
82 | * | |
83 | * -> ticket wakeup | |
84 | * Check if ->bytes == 0, if it does we got our reservation and we can carry | |
85 | * on, if not return the appropriate error (ENOSPC, but can be EINTR if we | |
86 | * were interrupted.) | |
87 | * | |
88 | * MAKING RESERVATIONS, FLUSHING HIGH PRIORITY | |
89 | * | |
90 | * Same as the above, except we add ourselves to the | |
91 | * space_info->priority_tickets, and we do not use ticket->wait, we simply | |
92 | * call flush_space() ourselves for the states that are safe for us to call | |
93 | * without deadlocking and hope for the best. | |
94 | * | |
95 | * THE FLUSHING STATES | |
96 | * | |
97 | * Generally speaking we will have two cases for each state, a "nice" state | |
98 | * and a "ALL THE THINGS" state. In btrfs we delay a lot of work in order to | |
99 | * reduce the locking over head on the various trees, and even to keep from | |
100 | * doing any work at all in the case of delayed refs. Each of these delayed | |
101 | * things however hold reservations, and so letting them run allows us to | |
102 | * reclaim space so we can make new reservations. | |
103 | * | |
104 | * FLUSH_DELAYED_ITEMS | |
105 | * Every inode has a delayed item to update the inode. Take a simple write | |
106 | * for example, we would update the inode item at write time to update the | |
107 | * mtime, and then again at finish_ordered_io() time in order to update the | |
108 | * isize or bytes. We keep these delayed items to coalesce these operations | |
109 | * into a single operation done on demand. These are an easy way to reclaim | |
110 | * metadata space. | |
111 | * | |
112 | * FLUSH_DELALLOC | |
113 | * Look at the delalloc comment to get an idea of how much space is reserved | |
114 | * for delayed allocation. We can reclaim some of this space simply by | |
115 | * running delalloc, but usually we need to wait for ordered extents to | |
116 | * reclaim the bulk of this space. | |
117 | * | |
118 | * FLUSH_DELAYED_REFS | |
119 | * We have a block reserve for the outstanding delayed refs space, and every | |
120 | * delayed ref operation holds a reservation. Running these is a quick way | |
121 | * to reclaim space, but we want to hold this until the end because COW can | |
122 | * churn a lot and we can avoid making some extent tree modifications if we | |
123 | * are able to delay for as long as possible. | |
124 | * | |
125 | * ALLOC_CHUNK | |
126 | * We will skip this the first time through space reservation, because of | |
127 | * overcommit and we don't want to have a lot of useless metadata space when | |
128 | * our worst case reservations will likely never come true. | |
129 | * | |
130 | * RUN_DELAYED_IPUTS | |
131 | * If we're freeing inodes we're likely freeing checksums, file extent | |
132 | * items, and extent tree items. Loads of space could be freed up by these | |
133 | * operations, however they won't be usable until the transaction commits. | |
134 | * | |
135 | * COMMIT_TRANS | |
136 | * may_commit_transaction() is the ultimate arbiter on whether we commit the | |
137 | * transaction or not. In order to avoid constantly churning we do all the | |
138 | * above flushing first and then commit the transaction as the last resort. | |
139 | * However we need to take into account things like pinned space that would | |
140 | * be freed, plus any delayed work we may not have gotten rid of in the case | |
141 | * of metadata. | |
142 | * | |
f00c42dd JB |
143 | * FORCE_COMMIT_TRANS |
144 | * For use by the preemptive flusher. We use this to bypass the ticketing | |
145 | * checks in may_commit_transaction, as we have more information about the | |
146 | * overall state of the system and may want to commit the transaction ahead | |
147 | * of actual ENOSPC conditions. | |
148 | * | |
4b8b0528 JB |
149 | * OVERCOMMIT |
150 | * | |
151 | * Because we hold so many reservations for metadata we will allow you to | |
152 | * reserve more space than is currently free in the currently allocate | |
153 | * metadata space. This only happens with metadata, data does not allow | |
154 | * overcommitting. | |
155 | * | |
156 | * You can see the current logic for when we allow overcommit in | |
157 | * btrfs_can_overcommit(), but it only applies to unallocated space. If there | |
158 | * is no unallocated space to be had, all reservations are kept within the | |
159 | * free space in the allocated metadata chunks. | |
160 | * | |
161 | * Because of overcommitting, you generally want to use the | |
162 | * btrfs_can_overcommit() logic for metadata allocations, as it does the right | |
163 | * thing with or without extra unallocated space. | |
164 | */ | |
165 | ||
e1f60a65 | 166 | u64 __pure btrfs_space_info_used(struct btrfs_space_info *s_info, |
280c2908 JB |
167 | bool may_use_included) |
168 | { | |
169 | ASSERT(s_info); | |
170 | return s_info->bytes_used + s_info->bytes_reserved + | |
171 | s_info->bytes_pinned + s_info->bytes_readonly + | |
169e0da9 | 172 | s_info->bytes_zone_unusable + |
280c2908 JB |
173 | (may_use_included ? s_info->bytes_may_use : 0); |
174 | } | |
175 | ||
176 | /* | |
177 | * after adding space to the filesystem, we need to clear the full flags | |
178 | * on all the space infos. | |
179 | */ | |
180 | void btrfs_clear_space_info_full(struct btrfs_fs_info *info) | |
181 | { | |
182 | struct list_head *head = &info->space_info; | |
183 | struct btrfs_space_info *found; | |
184 | ||
72804905 | 185 | list_for_each_entry(found, head, list) |
280c2908 | 186 | found->full = 0; |
280c2908 JB |
187 | } |
188 | ||
280c2908 JB |
189 | static int create_space_info(struct btrfs_fs_info *info, u64 flags) |
190 | { | |
191 | ||
192 | struct btrfs_space_info *space_info; | |
193 | int i; | |
194 | int ret; | |
195 | ||
196 | space_info = kzalloc(sizeof(*space_info), GFP_NOFS); | |
197 | if (!space_info) | |
198 | return -ENOMEM; | |
199 | ||
200 | ret = percpu_counter_init(&space_info->total_bytes_pinned, 0, | |
201 | GFP_KERNEL); | |
202 | if (ret) { | |
203 | kfree(space_info); | |
204 | return ret; | |
205 | } | |
206 | ||
207 | for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) | |
208 | INIT_LIST_HEAD(&space_info->block_groups[i]); | |
209 | init_rwsem(&space_info->groups_sem); | |
210 | spin_lock_init(&space_info->lock); | |
211 | space_info->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK; | |
212 | space_info->force_alloc = CHUNK_ALLOC_NO_FORCE; | |
280c2908 JB |
213 | INIT_LIST_HEAD(&space_info->ro_bgs); |
214 | INIT_LIST_HEAD(&space_info->tickets); | |
215 | INIT_LIST_HEAD(&space_info->priority_tickets); | |
88a777a6 | 216 | space_info->clamp = 1; |
280c2908 | 217 | |
b882327a DS |
218 | ret = btrfs_sysfs_add_space_info_type(info, space_info); |
219 | if (ret) | |
280c2908 | 220 | return ret; |
280c2908 | 221 | |
72804905 | 222 | list_add(&space_info->list, &info->space_info); |
280c2908 JB |
223 | if (flags & BTRFS_BLOCK_GROUP_DATA) |
224 | info->data_sinfo = space_info; | |
225 | ||
226 | return ret; | |
227 | } | |
228 | ||
229 | int btrfs_init_space_info(struct btrfs_fs_info *fs_info) | |
230 | { | |
231 | struct btrfs_super_block *disk_super; | |
232 | u64 features; | |
233 | u64 flags; | |
234 | int mixed = 0; | |
235 | int ret; | |
236 | ||
237 | disk_super = fs_info->super_copy; | |
238 | if (!btrfs_super_root(disk_super)) | |
239 | return -EINVAL; | |
240 | ||
241 | features = btrfs_super_incompat_flags(disk_super); | |
242 | if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) | |
243 | mixed = 1; | |
244 | ||
245 | flags = BTRFS_BLOCK_GROUP_SYSTEM; | |
246 | ret = create_space_info(fs_info, flags); | |
247 | if (ret) | |
248 | goto out; | |
249 | ||
250 | if (mixed) { | |
251 | flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA; | |
252 | ret = create_space_info(fs_info, flags); | |
253 | } else { | |
254 | flags = BTRFS_BLOCK_GROUP_METADATA; | |
255 | ret = create_space_info(fs_info, flags); | |
256 | if (ret) | |
257 | goto out; | |
258 | ||
259 | flags = BTRFS_BLOCK_GROUP_DATA; | |
260 | ret = create_space_info(fs_info, flags); | |
261 | } | |
262 | out: | |
263 | return ret; | |
264 | } | |
265 | ||
266 | void btrfs_update_space_info(struct btrfs_fs_info *info, u64 flags, | |
267 | u64 total_bytes, u64 bytes_used, | |
169e0da9 | 268 | u64 bytes_readonly, u64 bytes_zone_unusable, |
280c2908 JB |
269 | struct btrfs_space_info **space_info) |
270 | { | |
271 | struct btrfs_space_info *found; | |
272 | int factor; | |
273 | ||
274 | factor = btrfs_bg_type_to_factor(flags); | |
275 | ||
276 | found = btrfs_find_space_info(info, flags); | |
277 | ASSERT(found); | |
278 | spin_lock(&found->lock); | |
279 | found->total_bytes += total_bytes; | |
280 | found->disk_total += total_bytes * factor; | |
281 | found->bytes_used += bytes_used; | |
282 | found->disk_used += bytes_used * factor; | |
283 | found->bytes_readonly += bytes_readonly; | |
169e0da9 | 284 | found->bytes_zone_unusable += bytes_zone_unusable; |
280c2908 JB |
285 | if (total_bytes > 0) |
286 | found->full = 0; | |
18fa2284 | 287 | btrfs_try_granting_tickets(info, found); |
280c2908 JB |
288 | spin_unlock(&found->lock); |
289 | *space_info = found; | |
290 | } | |
291 | ||
292 | struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info, | |
293 | u64 flags) | |
294 | { | |
295 | struct list_head *head = &info->space_info; | |
296 | struct btrfs_space_info *found; | |
297 | ||
298 | flags &= BTRFS_BLOCK_GROUP_TYPE_MASK; | |
299 | ||
72804905 JB |
300 | list_for_each_entry(found, head, list) { |
301 | if (found->flags & flags) | |
280c2908 | 302 | return found; |
280c2908 | 303 | } |
280c2908 JB |
304 | return NULL; |
305 | } | |
41783ef2 | 306 | |
fa121a26 JB |
307 | static u64 calc_available_free_space(struct btrfs_fs_info *fs_info, |
308 | struct btrfs_space_info *space_info, | |
309 | enum btrfs_reserve_flush_enum flush) | |
41783ef2 | 310 | { |
41783ef2 | 311 | u64 profile; |
41783ef2 | 312 | u64 avail; |
41783ef2 JB |
313 | int factor; |
314 | ||
9f246926 | 315 | if (space_info->flags & BTRFS_BLOCK_GROUP_SYSTEM) |
41783ef2 JB |
316 | profile = btrfs_system_alloc_profile(fs_info); |
317 | else | |
318 | profile = btrfs_metadata_alloc_profile(fs_info); | |
319 | ||
41783ef2 JB |
320 | avail = atomic64_read(&fs_info->free_chunk_space); |
321 | ||
322 | /* | |
323 | * If we have dup, raid1 or raid10 then only half of the free | |
324 | * space is actually usable. For raid56, the space info used | |
325 | * doesn't include the parity drive, so we don't have to | |
326 | * change the math | |
327 | */ | |
328 | factor = btrfs_bg_type_to_factor(profile); | |
329 | avail = div_u64(avail, factor); | |
330 | ||
331 | /* | |
332 | * If we aren't flushing all things, let us overcommit up to | |
333 | * 1/2th of the space. If we can flush, don't let us overcommit | |
334 | * too much, let it overcommit up to 1/8 of the space. | |
335 | */ | |
336 | if (flush == BTRFS_RESERVE_FLUSH_ALL) | |
337 | avail >>= 3; | |
338 | else | |
339 | avail >>= 1; | |
fa121a26 JB |
340 | return avail; |
341 | } | |
342 | ||
343 | int btrfs_can_overcommit(struct btrfs_fs_info *fs_info, | |
344 | struct btrfs_space_info *space_info, u64 bytes, | |
345 | enum btrfs_reserve_flush_enum flush) | |
346 | { | |
347 | u64 avail; | |
348 | u64 used; | |
349 | ||
350 | /* Don't overcommit when in mixed mode */ | |
351 | if (space_info->flags & BTRFS_BLOCK_GROUP_DATA) | |
352 | return 0; | |
353 | ||
354 | used = btrfs_space_info_used(space_info, true); | |
355 | avail = calc_available_free_space(fs_info, space_info, flush); | |
41783ef2 JB |
356 | |
357 | if (used + bytes < space_info->total_bytes + avail) | |
358 | return 1; | |
359 | return 0; | |
360 | } | |
b338b013 | 361 | |
d611add4 FM |
362 | static void remove_ticket(struct btrfs_space_info *space_info, |
363 | struct reserve_ticket *ticket) | |
364 | { | |
365 | if (!list_empty(&ticket->list)) { | |
366 | list_del_init(&ticket->list); | |
367 | ASSERT(space_info->reclaim_size >= ticket->bytes); | |
368 | space_info->reclaim_size -= ticket->bytes; | |
369 | } | |
370 | } | |
371 | ||
b338b013 JB |
372 | /* |
373 | * This is for space we already have accounted in space_info->bytes_may_use, so | |
374 | * basically when we're returning space from block_rsv's. | |
375 | */ | |
18fa2284 JB |
376 | void btrfs_try_granting_tickets(struct btrfs_fs_info *fs_info, |
377 | struct btrfs_space_info *space_info) | |
b338b013 | 378 | { |
b338b013 | 379 | struct list_head *head; |
b338b013 | 380 | enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_NO_FLUSH; |
b338b013 | 381 | |
18fa2284 | 382 | lockdep_assert_held(&space_info->lock); |
b338b013 | 383 | |
18fa2284 | 384 | head = &space_info->priority_tickets; |
b338b013 | 385 | again: |
91182645 JB |
386 | while (!list_empty(head)) { |
387 | struct reserve_ticket *ticket; | |
388 | u64 used = btrfs_space_info_used(space_info, true); | |
389 | ||
390 | ticket = list_first_entry(head, struct reserve_ticket, list); | |
391 | ||
392 | /* Check and see if our ticket can be satisified now. */ | |
393 | if ((used + ticket->bytes <= space_info->total_bytes) || | |
a30a3d20 JB |
394 | btrfs_can_overcommit(fs_info, space_info, ticket->bytes, |
395 | flush)) { | |
91182645 JB |
396 | btrfs_space_info_update_bytes_may_use(fs_info, |
397 | space_info, | |
398 | ticket->bytes); | |
d611add4 | 399 | remove_ticket(space_info, ticket); |
b338b013 JB |
400 | ticket->bytes = 0; |
401 | space_info->tickets_id++; | |
402 | wake_up(&ticket->wait); | |
403 | } else { | |
91182645 | 404 | break; |
b338b013 JB |
405 | } |
406 | } | |
407 | ||
91182645 | 408 | if (head == &space_info->priority_tickets) { |
b338b013 JB |
409 | head = &space_info->tickets; |
410 | flush = BTRFS_RESERVE_FLUSH_ALL; | |
411 | goto again; | |
412 | } | |
b338b013 | 413 | } |
5da6afeb JB |
414 | |
415 | #define DUMP_BLOCK_RSV(fs_info, rsv_name) \ | |
416 | do { \ | |
417 | struct btrfs_block_rsv *__rsv = &(fs_info)->rsv_name; \ | |
418 | spin_lock(&__rsv->lock); \ | |
419 | btrfs_info(fs_info, #rsv_name ": size %llu reserved %llu", \ | |
420 | __rsv->size, __rsv->reserved); \ | |
421 | spin_unlock(&__rsv->lock); \ | |
422 | } while (0) | |
423 | ||
84fe47a4 JB |
424 | static void __btrfs_dump_space_info(struct btrfs_fs_info *fs_info, |
425 | struct btrfs_space_info *info) | |
5da6afeb | 426 | { |
84fe47a4 | 427 | lockdep_assert_held(&info->lock); |
5da6afeb | 428 | |
5da6afeb JB |
429 | btrfs_info(fs_info, "space_info %llu has %llu free, is %sfull", |
430 | info->flags, | |
431 | info->total_bytes - btrfs_space_info_used(info, true), | |
432 | info->full ? "" : "not "); | |
433 | btrfs_info(fs_info, | |
169e0da9 | 434 | "space_info total=%llu, used=%llu, pinned=%llu, reserved=%llu, may_use=%llu, readonly=%llu zone_unusable=%llu", |
5da6afeb JB |
435 | info->total_bytes, info->bytes_used, info->bytes_pinned, |
436 | info->bytes_reserved, info->bytes_may_use, | |
169e0da9 | 437 | info->bytes_readonly, info->bytes_zone_unusable); |
5da6afeb JB |
438 | |
439 | DUMP_BLOCK_RSV(fs_info, global_block_rsv); | |
440 | DUMP_BLOCK_RSV(fs_info, trans_block_rsv); | |
441 | DUMP_BLOCK_RSV(fs_info, chunk_block_rsv); | |
442 | DUMP_BLOCK_RSV(fs_info, delayed_block_rsv); | |
443 | DUMP_BLOCK_RSV(fs_info, delayed_refs_rsv); | |
444 | ||
84fe47a4 JB |
445 | } |
446 | ||
447 | void btrfs_dump_space_info(struct btrfs_fs_info *fs_info, | |
448 | struct btrfs_space_info *info, u64 bytes, | |
449 | int dump_block_groups) | |
450 | { | |
32da5386 | 451 | struct btrfs_block_group *cache; |
84fe47a4 JB |
452 | int index = 0; |
453 | ||
454 | spin_lock(&info->lock); | |
455 | __btrfs_dump_space_info(fs_info, info); | |
456 | spin_unlock(&info->lock); | |
457 | ||
5da6afeb JB |
458 | if (!dump_block_groups) |
459 | return; | |
460 | ||
461 | down_read(&info->groups_sem); | |
462 | again: | |
463 | list_for_each_entry(cache, &info->block_groups[index], list) { | |
464 | spin_lock(&cache->lock); | |
465 | btrfs_info(fs_info, | |
169e0da9 | 466 | "block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %llu zone_unusable %s", |
b3470b5d | 467 | cache->start, cache->length, cache->used, cache->pinned, |
169e0da9 NA |
468 | cache->reserved, cache->zone_unusable, |
469 | cache->ro ? "[readonly]" : ""); | |
5da6afeb | 470 | spin_unlock(&cache->lock); |
ab0db043 | 471 | btrfs_dump_free_space(cache, bytes); |
5da6afeb JB |
472 | } |
473 | if (++index < BTRFS_NR_RAID_TYPES) | |
474 | goto again; | |
475 | up_read(&info->groups_sem); | |
476 | } | |
0d9764f6 | 477 | |
0d9764f6 JB |
478 | static inline u64 calc_reclaim_items_nr(struct btrfs_fs_info *fs_info, |
479 | u64 to_reclaim) | |
480 | { | |
481 | u64 bytes; | |
482 | u64 nr; | |
483 | ||
2bd36e7b | 484 | bytes = btrfs_calc_insert_metadata_size(fs_info, 1); |
0d9764f6 JB |
485 | nr = div64_u64(to_reclaim, bytes); |
486 | if (!nr) | |
487 | nr = 1; | |
488 | return nr; | |
489 | } | |
490 | ||
491 | #define EXTENT_SIZE_PER_ITEM SZ_256K | |
492 | ||
493 | /* | |
494 | * shrink metadata reservation for delalloc | |
495 | */ | |
920a9958 JB |
496 | static void shrink_delalloc(struct btrfs_fs_info *fs_info, |
497 | struct btrfs_space_info *space_info, | |
498 | u64 to_reclaim, bool wait_ordered) | |
0d9764f6 | 499 | { |
0d9764f6 JB |
500 | struct btrfs_trans_handle *trans; |
501 | u64 delalloc_bytes; | |
5deb17e1 | 502 | u64 ordered_bytes; |
0d9764f6 JB |
503 | u64 items; |
504 | long time_left; | |
0d9764f6 JB |
505 | int loops; |
506 | ||
507 | /* Calc the number of the pages we need flush for space reservation */ | |
d7f81fac JB |
508 | if (to_reclaim == U64_MAX) { |
509 | items = U64_MAX; | |
510 | } else { | |
511 | /* | |
512 | * to_reclaim is set to however much metadata we need to | |
513 | * reclaim, but reclaiming that much data doesn't really track | |
514 | * exactly, so increase the amount to reclaim by 2x in order to | |
515 | * make sure we're flushing enough delalloc to hopefully reclaim | |
516 | * some metadata reservations. | |
517 | */ | |
518 | items = calc_reclaim_items_nr(fs_info, to_reclaim) * 2; | |
519 | to_reclaim = items * EXTENT_SIZE_PER_ITEM; | |
520 | } | |
0d9764f6 JB |
521 | |
522 | trans = (struct btrfs_trans_handle *)current->journal_info; | |
0d9764f6 JB |
523 | |
524 | delalloc_bytes = percpu_counter_sum_positive( | |
525 | &fs_info->delalloc_bytes); | |
5deb17e1 JB |
526 | ordered_bytes = percpu_counter_sum_positive(&fs_info->ordered_bytes); |
527 | if (delalloc_bytes == 0 && ordered_bytes == 0) | |
0d9764f6 | 528 | return; |
0d9764f6 JB |
529 | |
530 | /* | |
531 | * If we are doing more ordered than delalloc we need to just wait on | |
532 | * ordered extents, otherwise we'll waste time trying to flush delalloc | |
533 | * that likely won't give us the space back we need. | |
534 | */ | |
5deb17e1 | 535 | if (ordered_bytes > delalloc_bytes) |
0d9764f6 JB |
536 | wait_ordered = true; |
537 | ||
538 | loops = 0; | |
5deb17e1 | 539 | while ((delalloc_bytes || ordered_bytes) && loops < 3) { |
9db4dc24 NB |
540 | u64 temp = min(delalloc_bytes, to_reclaim) >> PAGE_SHIFT; |
541 | long nr_pages = min_t(u64, temp, LONG_MAX); | |
e076ab2a JB |
542 | |
543 | btrfs_start_delalloc_roots(fs_info, nr_pages, true); | |
0d9764f6 | 544 | |
0d9764f6 JB |
545 | loops++; |
546 | if (wait_ordered && !trans) { | |
547 | btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1); | |
548 | } else { | |
549 | time_left = schedule_timeout_killable(1); | |
550 | if (time_left) | |
551 | break; | |
552 | } | |
448b966b JB |
553 | |
554 | spin_lock(&space_info->lock); | |
555 | if (list_empty(&space_info->tickets) && | |
556 | list_empty(&space_info->priority_tickets)) { | |
557 | spin_unlock(&space_info->lock); | |
558 | break; | |
559 | } | |
560 | spin_unlock(&space_info->lock); | |
561 | ||
0d9764f6 JB |
562 | delalloc_bytes = percpu_counter_sum_positive( |
563 | &fs_info->delalloc_bytes); | |
5deb17e1 JB |
564 | ordered_bytes = percpu_counter_sum_positive( |
565 | &fs_info->ordered_bytes); | |
0d9764f6 JB |
566 | } |
567 | } | |
568 | ||
569 | /** | |
d98b188e NB |
570 | * Possibly commit the transaction if its ok to |
571 | * | |
572 | * @fs_info: the filesystem | |
573 | * @space_info: space_info we are checking for commit, either data or metadata | |
0d9764f6 JB |
574 | * |
575 | * This will check to make sure that committing the transaction will actually | |
576 | * get us somewhere and then commit the transaction if it does. Otherwise it | |
577 | * will return -ENOSPC. | |
578 | */ | |
579 | static int may_commit_transaction(struct btrfs_fs_info *fs_info, | |
bb86bd3d | 580 | struct btrfs_space_info *space_info) |
0d9764f6 JB |
581 | { |
582 | struct reserve_ticket *ticket = NULL; | |
583 | struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_block_rsv; | |
584 | struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv; | |
bb4f58a7 | 585 | struct btrfs_block_rsv *trans_rsv = &fs_info->trans_block_rsv; |
0d9764f6 | 586 | struct btrfs_trans_handle *trans; |
0d9764f6 | 587 | u64 reclaim_bytes = 0; |
bb86bd3d | 588 | u64 bytes_needed = 0; |
00c0135e | 589 | u64 cur_free_bytes = 0; |
0d9764f6 JB |
590 | |
591 | trans = (struct btrfs_trans_handle *)current->journal_info; | |
592 | if (trans) | |
593 | return -EAGAIN; | |
594 | ||
595 | spin_lock(&space_info->lock); | |
00c0135e JB |
596 | cur_free_bytes = btrfs_space_info_used(space_info, true); |
597 | if (cur_free_bytes < space_info->total_bytes) | |
598 | cur_free_bytes = space_info->total_bytes - cur_free_bytes; | |
599 | else | |
600 | cur_free_bytes = 0; | |
601 | ||
0d9764f6 JB |
602 | if (!list_empty(&space_info->priority_tickets)) |
603 | ticket = list_first_entry(&space_info->priority_tickets, | |
604 | struct reserve_ticket, list); | |
605 | else if (!list_empty(&space_info->tickets)) | |
606 | ticket = list_first_entry(&space_info->tickets, | |
607 | struct reserve_ticket, list); | |
a1ed0a82 JB |
608 | if (ticket) |
609 | bytes_needed = ticket->bytes; | |
00c0135e JB |
610 | |
611 | if (bytes_needed > cur_free_bytes) | |
612 | bytes_needed -= cur_free_bytes; | |
613 | else | |
614 | bytes_needed = 0; | |
0d9764f6 JB |
615 | spin_unlock(&space_info->lock); |
616 | ||
617 | if (!bytes_needed) | |
618 | return 0; | |
619 | ||
620 | trans = btrfs_join_transaction(fs_info->extent_root); | |
621 | if (IS_ERR(trans)) | |
622 | return PTR_ERR(trans); | |
623 | ||
624 | /* | |
625 | * See if there is enough pinned space to make this reservation, or if | |
626 | * we have block groups that are going to be freed, allowing us to | |
627 | * possibly do a chunk allocation the next loop through. | |
628 | */ | |
bb86bd3d | 629 | if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags) || |
0d9764f6 JB |
630 | __percpu_counter_compare(&space_info->total_bytes_pinned, |
631 | bytes_needed, | |
632 | BTRFS_TOTAL_BYTES_PINNED_BATCH) >= 0) | |
633 | goto commit; | |
634 | ||
635 | /* | |
a1ed0a82 JB |
636 | * See if there is some space in the delayed insertion reserve for this |
637 | * reservation. If the space_info's don't match (like for DATA or | |
638 | * SYSTEM) then just go enospc, reclaiming this space won't recover any | |
639 | * space to satisfy those reservations. | |
0d9764f6 JB |
640 | */ |
641 | if (space_info != delayed_rsv->space_info) | |
642 | goto enospc; | |
643 | ||
644 | spin_lock(&delayed_rsv->lock); | |
645 | reclaim_bytes += delayed_rsv->reserved; | |
646 | spin_unlock(&delayed_rsv->lock); | |
647 | ||
648 | spin_lock(&delayed_refs_rsv->lock); | |
649 | reclaim_bytes += delayed_refs_rsv->reserved; | |
650 | spin_unlock(&delayed_refs_rsv->lock); | |
bb4f58a7 JB |
651 | |
652 | spin_lock(&trans_rsv->lock); | |
653 | reclaim_bytes += trans_rsv->reserved; | |
654 | spin_unlock(&trans_rsv->lock); | |
655 | ||
0d9764f6 JB |
656 | if (reclaim_bytes >= bytes_needed) |
657 | goto commit; | |
658 | bytes_needed -= reclaim_bytes; | |
659 | ||
660 | if (__percpu_counter_compare(&space_info->total_bytes_pinned, | |
661 | bytes_needed, | |
662 | BTRFS_TOTAL_BYTES_PINNED_BATCH) < 0) | |
663 | goto enospc; | |
664 | ||
665 | commit: | |
666 | return btrfs_commit_transaction(trans); | |
667 | enospc: | |
668 | btrfs_end_transaction(trans); | |
669 | return -ENOSPC; | |
670 | } | |
671 | ||
672 | /* | |
673 | * Try to flush some data based on policy set by @state. This is only advisory | |
674 | * and may fail for various reasons. The caller is supposed to examine the | |
675 | * state of @space_info to detect the outcome. | |
676 | */ | |
677 | static void flush_space(struct btrfs_fs_info *fs_info, | |
678 | struct btrfs_space_info *space_info, u64 num_bytes, | |
4b02b00f | 679 | enum btrfs_flush_state state, bool for_preempt) |
0d9764f6 JB |
680 | { |
681 | struct btrfs_root *root = fs_info->extent_root; | |
682 | struct btrfs_trans_handle *trans; | |
683 | int nr; | |
684 | int ret = 0; | |
685 | ||
686 | switch (state) { | |
687 | case FLUSH_DELAYED_ITEMS_NR: | |
688 | case FLUSH_DELAYED_ITEMS: | |
689 | if (state == FLUSH_DELAYED_ITEMS_NR) | |
690 | nr = calc_reclaim_items_nr(fs_info, num_bytes) * 2; | |
691 | else | |
692 | nr = -1; | |
693 | ||
694 | trans = btrfs_join_transaction(root); | |
695 | if (IS_ERR(trans)) { | |
696 | ret = PTR_ERR(trans); | |
697 | break; | |
698 | } | |
699 | ret = btrfs_run_delayed_items_nr(trans, nr); | |
700 | btrfs_end_transaction(trans); | |
701 | break; | |
702 | case FLUSH_DELALLOC: | |
703 | case FLUSH_DELALLOC_WAIT: | |
920a9958 | 704 | shrink_delalloc(fs_info, space_info, num_bytes, |
0d9764f6 JB |
705 | state == FLUSH_DELALLOC_WAIT); |
706 | break; | |
707 | case FLUSH_DELAYED_REFS_NR: | |
708 | case FLUSH_DELAYED_REFS: | |
709 | trans = btrfs_join_transaction(root); | |
710 | if (IS_ERR(trans)) { | |
711 | ret = PTR_ERR(trans); | |
712 | break; | |
713 | } | |
714 | if (state == FLUSH_DELAYED_REFS_NR) | |
715 | nr = calc_reclaim_items_nr(fs_info, num_bytes); | |
716 | else | |
717 | nr = 0; | |
718 | btrfs_run_delayed_refs(trans, nr); | |
719 | btrfs_end_transaction(trans); | |
720 | break; | |
721 | case ALLOC_CHUNK: | |
722 | case ALLOC_CHUNK_FORCE: | |
723 | trans = btrfs_join_transaction(root); | |
724 | if (IS_ERR(trans)) { | |
725 | ret = PTR_ERR(trans); | |
726 | break; | |
727 | } | |
728 | ret = btrfs_chunk_alloc(trans, | |
c6c45303 | 729 | btrfs_get_alloc_profile(fs_info, space_info->flags), |
0d9764f6 JB |
730 | (state == ALLOC_CHUNK) ? CHUNK_ALLOC_NO_FORCE : |
731 | CHUNK_ALLOC_FORCE); | |
732 | btrfs_end_transaction(trans); | |
733 | if (ret > 0 || ret == -ENOSPC) | |
734 | ret = 0; | |
735 | break; | |
844245b4 | 736 | case RUN_DELAYED_IPUTS: |
0d9764f6 JB |
737 | /* |
738 | * If we have pending delayed iputs then we could free up a | |
739 | * bunch of pinned space, so make sure we run the iputs before | |
740 | * we do our pinned bytes check below. | |
741 | */ | |
742 | btrfs_run_delayed_iputs(fs_info); | |
743 | btrfs_wait_on_delayed_iputs(fs_info); | |
844245b4 JB |
744 | break; |
745 | case COMMIT_TRANS: | |
bb86bd3d | 746 | ret = may_commit_transaction(fs_info, space_info); |
0d9764f6 | 747 | break; |
f00c42dd JB |
748 | case FORCE_COMMIT_TRANS: |
749 | trans = btrfs_join_transaction(root); | |
750 | if (IS_ERR(trans)) { | |
751 | ret = PTR_ERR(trans); | |
752 | break; | |
753 | } | |
754 | ret = btrfs_commit_transaction(trans); | |
755 | break; | |
0d9764f6 JB |
756 | default: |
757 | ret = -ENOSPC; | |
758 | break; | |
759 | } | |
760 | ||
761 | trace_btrfs_flush_space(fs_info, space_info->flags, num_bytes, state, | |
4b02b00f | 762 | ret, for_preempt); |
0d9764f6 JB |
763 | return; |
764 | } | |
765 | ||
766 | static inline u64 | |
767 | btrfs_calc_reclaim_metadata_size(struct btrfs_fs_info *fs_info, | |
9f246926 | 768 | struct btrfs_space_info *space_info) |
0d9764f6 | 769 | { |
0d9764f6 | 770 | u64 used; |
fa121a26 | 771 | u64 avail; |
db161806 | 772 | u64 to_reclaim = space_info->reclaim_size; |
0d9764f6 | 773 | |
db161806 | 774 | lockdep_assert_held(&space_info->lock); |
fa121a26 JB |
775 | |
776 | avail = calc_available_free_space(fs_info, space_info, | |
777 | BTRFS_RESERVE_FLUSH_ALL); | |
778 | used = btrfs_space_info_used(space_info, true); | |
779 | ||
780 | /* | |
781 | * We may be flushing because suddenly we have less space than we had | |
782 | * before, and now we're well over-committed based on our current free | |
783 | * space. If that's the case add in our overage so we make sure to put | |
784 | * appropriate pressure on the flushing state machine. | |
785 | */ | |
786 | if (space_info->total_bytes + avail < used) | |
787 | to_reclaim += used - (space_info->total_bytes + avail); | |
788 | ||
0d9764f6 JB |
789 | return to_reclaim; |
790 | } | |
791 | ||
ae7913ba | 792 | static bool need_preemptive_reclaim(struct btrfs_fs_info *fs_info, |
2e294c60 | 793 | struct btrfs_space_info *space_info) |
0d9764f6 | 794 | { |
2e294c60 | 795 | u64 ordered, delalloc; |
0d9764f6 | 796 | u64 thresh = div_factor_fine(space_info->total_bytes, 98); |
2e294c60 | 797 | u64 used; |
0d9764f6 JB |
798 | |
799 | /* If we're just plain full then async reclaim just slows us down. */ | |
800 | if ((space_info->bytes_used + space_info->bytes_reserved) >= thresh) | |
ae7913ba | 801 | return false; |
0d9764f6 | 802 | |
f205edf7 JB |
803 | /* |
804 | * We have tickets queued, bail so we don't compete with the async | |
805 | * flushers. | |
806 | */ | |
807 | if (space_info->reclaim_size) | |
808 | return false; | |
809 | ||
2e294c60 JB |
810 | /* |
811 | * If we have over half of the free space occupied by reservations or | |
812 | * pinned then we want to start flushing. | |
813 | * | |
814 | * We do not do the traditional thing here, which is to say | |
815 | * | |
816 | * if (used >= ((total_bytes + avail) / 2)) | |
817 | * return 1; | |
818 | * | |
819 | * because this doesn't quite work how we want. If we had more than 50% | |
820 | * of the space_info used by bytes_used and we had 0 available we'd just | |
821 | * constantly run the background flusher. Instead we want it to kick in | |
88a777a6 JB |
822 | * if our reclaimable space exceeds our clamped free space. |
823 | * | |
824 | * Our clamping range is 2^1 -> 2^8. Practically speaking that means | |
825 | * the following: | |
826 | * | |
827 | * Amount of RAM Minimum threshold Maximum threshold | |
828 | * | |
829 | * 256GiB 1GiB 128GiB | |
830 | * 128GiB 512MiB 64GiB | |
831 | * 64GiB 256MiB 32GiB | |
832 | * 32GiB 128MiB 16GiB | |
833 | * 16GiB 64MiB 8GiB | |
834 | * | |
835 | * These are the range our thresholds will fall in, corresponding to how | |
836 | * much delalloc we need for the background flusher to kick in. | |
2e294c60 | 837 | */ |
88a777a6 | 838 | |
2e294c60 JB |
839 | thresh = calc_available_free_space(fs_info, space_info, |
840 | BTRFS_RESERVE_FLUSH_ALL); | |
841 | thresh += (space_info->total_bytes - space_info->bytes_used - | |
842 | space_info->bytes_reserved - space_info->bytes_readonly); | |
88a777a6 | 843 | thresh >>= space_info->clamp; |
9f42d377 | 844 | |
2e294c60 | 845 | used = space_info->bytes_pinned; |
9f42d377 | 846 | |
2e294c60 JB |
847 | /* |
848 | * If we have more ordered bytes than delalloc bytes then we're either | |
849 | * doing a lot of DIO, or we simply don't have a lot of delalloc waiting | |
850 | * around. Preemptive flushing is only useful in that it can free up | |
851 | * space before tickets need to wait for things to finish. In the case | |
852 | * of ordered extents, preemptively waiting on ordered extents gets us | |
853 | * nothing, if our reservations are tied up in ordered extents we'll | |
854 | * simply have to slow down writers by forcing them to wait on ordered | |
855 | * extents. | |
856 | * | |
857 | * In the case that ordered is larger than delalloc, only include the | |
858 | * block reserves that we would actually be able to directly reclaim | |
859 | * from. In this case if we're heavy on metadata operations this will | |
860 | * clearly be heavy enough to warrant preemptive flushing. In the case | |
861 | * of heavy DIO or ordered reservations, preemptive flushing will just | |
862 | * waste time and cause us to slow down. | |
863 | */ | |
2cdb3909 JB |
864 | ordered = percpu_counter_read_positive(&fs_info->ordered_bytes); |
865 | delalloc = percpu_counter_read_positive(&fs_info->delalloc_bytes); | |
2e294c60 JB |
866 | if (ordered >= delalloc) |
867 | used += fs_info->delayed_refs_rsv.reserved + | |
868 | fs_info->delayed_block_rsv.reserved; | |
9f42d377 | 869 | else |
2e294c60 | 870 | used += space_info->bytes_may_use; |
0d9764f6 JB |
871 | |
872 | return (used >= thresh && !btrfs_fs_closing(fs_info) && | |
873 | !test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state)); | |
874 | } | |
875 | ||
7f9fe614 JB |
876 | static bool steal_from_global_rsv(struct btrfs_fs_info *fs_info, |
877 | struct btrfs_space_info *space_info, | |
878 | struct reserve_ticket *ticket) | |
879 | { | |
880 | struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv; | |
881 | u64 min_bytes; | |
882 | ||
883 | if (global_rsv->space_info != space_info) | |
884 | return false; | |
885 | ||
886 | spin_lock(&global_rsv->lock); | |
e6549c2a | 887 | min_bytes = div_factor(global_rsv->size, 1); |
7f9fe614 JB |
888 | if (global_rsv->reserved < min_bytes + ticket->bytes) { |
889 | spin_unlock(&global_rsv->lock); | |
890 | return false; | |
891 | } | |
892 | global_rsv->reserved -= ticket->bytes; | |
6d548b9e | 893 | remove_ticket(space_info, ticket); |
7f9fe614 | 894 | ticket->bytes = 0; |
7f9fe614 JB |
895 | wake_up(&ticket->wait); |
896 | space_info->tickets_id++; | |
897 | if (global_rsv->reserved < global_rsv->size) | |
898 | global_rsv->full = 0; | |
899 | spin_unlock(&global_rsv->lock); | |
900 | ||
901 | return true; | |
902 | } | |
903 | ||
2341ccd1 JB |
904 | /* |
905 | * maybe_fail_all_tickets - we've exhausted our flushing, start failing tickets | |
906 | * @fs_info - fs_info for this fs | |
907 | * @space_info - the space info we were flushing | |
908 | * | |
909 | * We call this when we've exhausted our flushing ability and haven't made | |
910 | * progress in satisfying tickets. The reservation code handles tickets in | |
911 | * order, so if there is a large ticket first and then smaller ones we could | |
912 | * very well satisfy the smaller tickets. This will attempt to wake up any | |
913 | * tickets in the list to catch this case. | |
914 | * | |
915 | * This function returns true if it was able to make progress by clearing out | |
916 | * other tickets, or if it stumbles across a ticket that was smaller than the | |
917 | * first ticket. | |
918 | */ | |
919 | static bool maybe_fail_all_tickets(struct btrfs_fs_info *fs_info, | |
920 | struct btrfs_space_info *space_info) | |
0d9764f6 JB |
921 | { |
922 | struct reserve_ticket *ticket; | |
2341ccd1 JB |
923 | u64 tickets_id = space_info->tickets_id; |
924 | u64 first_ticket_bytes = 0; | |
925 | ||
84fe47a4 JB |
926 | if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) { |
927 | btrfs_info(fs_info, "cannot satisfy tickets, dumping space info"); | |
928 | __btrfs_dump_space_info(fs_info, space_info); | |
929 | } | |
930 | ||
2341ccd1 JB |
931 | while (!list_empty(&space_info->tickets) && |
932 | tickets_id == space_info->tickets_id) { | |
933 | ticket = list_first_entry(&space_info->tickets, | |
934 | struct reserve_ticket, list); | |
935 | ||
7f9fe614 JB |
936 | if (ticket->steal && |
937 | steal_from_global_rsv(fs_info, space_info, ticket)) | |
938 | return true; | |
939 | ||
2341ccd1 JB |
940 | /* |
941 | * may_commit_transaction will avoid committing the transaction | |
942 | * if it doesn't feel like the space reclaimed by the commit | |
943 | * would result in the ticket succeeding. However if we have a | |
944 | * smaller ticket in the queue it may be small enough to be | |
945 | * satisified by committing the transaction, so if any | |
946 | * subsequent ticket is smaller than the first ticket go ahead | |
947 | * and send us back for another loop through the enospc flushing | |
948 | * code. | |
949 | */ | |
950 | if (first_ticket_bytes == 0) | |
951 | first_ticket_bytes = ticket->bytes; | |
952 | else if (first_ticket_bytes > ticket->bytes) | |
953 | return true; | |
0d9764f6 | 954 | |
84fe47a4 JB |
955 | if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) |
956 | btrfs_info(fs_info, "failing ticket with %llu bytes", | |
957 | ticket->bytes); | |
958 | ||
d611add4 | 959 | remove_ticket(space_info, ticket); |
0d9764f6 JB |
960 | ticket->error = -ENOSPC; |
961 | wake_up(&ticket->wait); | |
2341ccd1 JB |
962 | |
963 | /* | |
964 | * We're just throwing tickets away, so more flushing may not | |
965 | * trip over btrfs_try_granting_tickets, so we need to call it | |
966 | * here to see if we can make progress with the next ticket in | |
967 | * the list. | |
968 | */ | |
969 | btrfs_try_granting_tickets(fs_info, space_info); | |
0d9764f6 | 970 | } |
2341ccd1 | 971 | return (tickets_id != space_info->tickets_id); |
0d9764f6 JB |
972 | } |
973 | ||
974 | /* | |
975 | * This is for normal flushers, we can wait all goddamned day if we want to. We | |
976 | * will loop and continuously try to flush as long as we are making progress. | |
977 | * We count progress as clearing off tickets each time we have to loop. | |
978 | */ | |
979 | static void btrfs_async_reclaim_metadata_space(struct work_struct *work) | |
980 | { | |
981 | struct btrfs_fs_info *fs_info; | |
982 | struct btrfs_space_info *space_info; | |
983 | u64 to_reclaim; | |
91e79a83 | 984 | enum btrfs_flush_state flush_state; |
0d9764f6 JB |
985 | int commit_cycles = 0; |
986 | u64 last_tickets_id; | |
987 | ||
988 | fs_info = container_of(work, struct btrfs_fs_info, async_reclaim_work); | |
989 | space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA); | |
990 | ||
991 | spin_lock(&space_info->lock); | |
9f246926 | 992 | to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info); |
0d9764f6 JB |
993 | if (!to_reclaim) { |
994 | space_info->flush = 0; | |
995 | spin_unlock(&space_info->lock); | |
996 | return; | |
997 | } | |
998 | last_tickets_id = space_info->tickets_id; | |
999 | spin_unlock(&space_info->lock); | |
1000 | ||
1001 | flush_state = FLUSH_DELAYED_ITEMS_NR; | |
1002 | do { | |
4b02b00f | 1003 | flush_space(fs_info, space_info, to_reclaim, flush_state, false); |
0d9764f6 JB |
1004 | spin_lock(&space_info->lock); |
1005 | if (list_empty(&space_info->tickets)) { | |
1006 | space_info->flush = 0; | |
1007 | spin_unlock(&space_info->lock); | |
1008 | return; | |
1009 | } | |
1010 | to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, | |
9f246926 | 1011 | space_info); |
0d9764f6 JB |
1012 | if (last_tickets_id == space_info->tickets_id) { |
1013 | flush_state++; | |
1014 | } else { | |
1015 | last_tickets_id = space_info->tickets_id; | |
1016 | flush_state = FLUSH_DELAYED_ITEMS_NR; | |
1017 | if (commit_cycles) | |
1018 | commit_cycles--; | |
1019 | } | |
1020 | ||
1021 | /* | |
1022 | * We don't want to force a chunk allocation until we've tried | |
1023 | * pretty hard to reclaim space. Think of the case where we | |
1024 | * freed up a bunch of space and so have a lot of pinned space | |
1025 | * to reclaim. We would rather use that than possibly create a | |
1026 | * underutilized metadata chunk. So if this is our first run | |
1027 | * through the flushing state machine skip ALLOC_CHUNK_FORCE and | |
1028 | * commit the transaction. If nothing has changed the next go | |
1029 | * around then we can force a chunk allocation. | |
1030 | */ | |
1031 | if (flush_state == ALLOC_CHUNK_FORCE && !commit_cycles) | |
1032 | flush_state++; | |
1033 | ||
1034 | if (flush_state > COMMIT_TRANS) { | |
1035 | commit_cycles++; | |
1036 | if (commit_cycles > 2) { | |
2341ccd1 | 1037 | if (maybe_fail_all_tickets(fs_info, space_info)) { |
0d9764f6 JB |
1038 | flush_state = FLUSH_DELAYED_ITEMS_NR; |
1039 | commit_cycles--; | |
1040 | } else { | |
1041 | space_info->flush = 0; | |
1042 | } | |
1043 | } else { | |
1044 | flush_state = FLUSH_DELAYED_ITEMS_NR; | |
1045 | } | |
1046 | } | |
1047 | spin_unlock(&space_info->lock); | |
1048 | } while (flush_state <= COMMIT_TRANS); | |
1049 | } | |
1050 | ||
576fa348 JB |
1051 | /* |
1052 | * This handles pre-flushing of metadata space before we get to the point that | |
1053 | * we need to start blocking threads on tickets. The logic here is different | |
1054 | * from the other flush paths because it doesn't rely on tickets to tell us how | |
1055 | * much we need to flush, instead it attempts to keep us below the 80% full | |
1056 | * watermark of space by flushing whichever reservation pool is currently the | |
1057 | * largest. | |
1058 | */ | |
1059 | static void btrfs_preempt_reclaim_metadata_space(struct work_struct *work) | |
1060 | { | |
1061 | struct btrfs_fs_info *fs_info; | |
1062 | struct btrfs_space_info *space_info; | |
1063 | struct btrfs_block_rsv *delayed_block_rsv; | |
1064 | struct btrfs_block_rsv *delayed_refs_rsv; | |
1065 | struct btrfs_block_rsv *global_rsv; | |
1066 | struct btrfs_block_rsv *trans_rsv; | |
88a777a6 | 1067 | int loops = 0; |
576fa348 JB |
1068 | |
1069 | fs_info = container_of(work, struct btrfs_fs_info, | |
1070 | preempt_reclaim_work); | |
1071 | space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA); | |
1072 | delayed_block_rsv = &fs_info->delayed_block_rsv; | |
1073 | delayed_refs_rsv = &fs_info->delayed_refs_rsv; | |
1074 | global_rsv = &fs_info->global_block_rsv; | |
1075 | trans_rsv = &fs_info->trans_block_rsv; | |
1076 | ||
1077 | spin_lock(&space_info->lock); | |
2e294c60 | 1078 | while (need_preemptive_reclaim(fs_info, space_info)) { |
576fa348 JB |
1079 | enum btrfs_flush_state flush; |
1080 | u64 delalloc_size = 0; | |
1081 | u64 to_reclaim, block_rsv_size; | |
1082 | u64 global_rsv_size = global_rsv->reserved; | |
1083 | ||
88a777a6 JB |
1084 | loops++; |
1085 | ||
576fa348 JB |
1086 | /* |
1087 | * We don't have a precise counter for the metadata being | |
1088 | * reserved for delalloc, so we'll approximate it by subtracting | |
1089 | * out the block rsv's space from the bytes_may_use. If that | |
1090 | * amount is higher than the individual reserves, then we can | |
1091 | * assume it's tied up in delalloc reservations. | |
1092 | */ | |
1093 | block_rsv_size = global_rsv_size + | |
1094 | delayed_block_rsv->reserved + | |
1095 | delayed_refs_rsv->reserved + | |
1096 | trans_rsv->reserved; | |
1097 | if (block_rsv_size < space_info->bytes_may_use) | |
1098 | delalloc_size = space_info->bytes_may_use - block_rsv_size; | |
1099 | spin_unlock(&space_info->lock); | |
1100 | ||
1101 | /* | |
1102 | * We don't want to include the global_rsv in our calculation, | |
1103 | * because that's space we can't touch. Subtract it from the | |
1104 | * block_rsv_size for the next checks. | |
1105 | */ | |
1106 | block_rsv_size -= global_rsv_size; | |
1107 | ||
1108 | /* | |
1109 | * We really want to avoid flushing delalloc too much, as it | |
1110 | * could result in poor allocation patterns, so only flush it if | |
1111 | * it's larger than the rest of the pools combined. | |
1112 | */ | |
1113 | if (delalloc_size > block_rsv_size) { | |
1114 | to_reclaim = delalloc_size; | |
1115 | flush = FLUSH_DELALLOC; | |
1116 | } else if (space_info->bytes_pinned > | |
1117 | (delayed_block_rsv->reserved + | |
1118 | delayed_refs_rsv->reserved)) { | |
1119 | to_reclaim = space_info->bytes_pinned; | |
1120 | flush = FORCE_COMMIT_TRANS; | |
1121 | } else if (delayed_block_rsv->reserved > | |
1122 | delayed_refs_rsv->reserved) { | |
1123 | to_reclaim = delayed_block_rsv->reserved; | |
1124 | flush = FLUSH_DELAYED_ITEMS_NR; | |
1125 | } else { | |
1126 | to_reclaim = delayed_refs_rsv->reserved; | |
1127 | flush = FLUSH_DELAYED_REFS_NR; | |
1128 | } | |
1129 | ||
1130 | /* | |
1131 | * We don't want to reclaim everything, just a portion, so scale | |
1132 | * down the to_reclaim by 1/4. If it takes us down to 0, | |
1133 | * reclaim 1 items worth. | |
1134 | */ | |
1135 | to_reclaim >>= 2; | |
1136 | if (!to_reclaim) | |
1137 | to_reclaim = btrfs_calc_insert_metadata_size(fs_info, 1); | |
4b02b00f | 1138 | flush_space(fs_info, space_info, to_reclaim, flush, true); |
576fa348 JB |
1139 | cond_resched(); |
1140 | spin_lock(&space_info->lock); | |
576fa348 | 1141 | } |
88a777a6 JB |
1142 | |
1143 | /* We only went through once, back off our clamping. */ | |
1144 | if (loops == 1 && !space_info->reclaim_size) | |
1145 | space_info->clamp = max(1, space_info->clamp - 1); | |
e5ad49e2 | 1146 | trace_btrfs_done_preemptive_reclaim(fs_info, space_info); |
576fa348 JB |
1147 | spin_unlock(&space_info->lock); |
1148 | } | |
1149 | ||
1a7a92c8 JB |
1150 | /* |
1151 | * FLUSH_DELALLOC_WAIT: | |
1152 | * Space is freed from flushing delalloc in one of two ways. | |
1153 | * | |
1154 | * 1) compression is on and we allocate less space than we reserved | |
1155 | * 2) we are overwriting existing space | |
1156 | * | |
1157 | * For #1 that extra space is reclaimed as soon as the delalloc pages are | |
1158 | * COWed, by way of btrfs_add_reserved_bytes() which adds the actual extent | |
1159 | * length to ->bytes_reserved, and subtracts the reserved space from | |
1160 | * ->bytes_may_use. | |
1161 | * | |
1162 | * For #2 this is trickier. Once the ordered extent runs we will drop the | |
1163 | * extent in the range we are overwriting, which creates a delayed ref for | |
1164 | * that freed extent. This however is not reclaimed until the transaction | |
1165 | * commits, thus the next stages. | |
1166 | * | |
1167 | * RUN_DELAYED_IPUTS | |
1168 | * If we are freeing inodes, we want to make sure all delayed iputs have | |
1169 | * completed, because they could have been on an inode with i_nlink == 0, and | |
1170 | * thus have been truncated and freed up space. But again this space is not | |
1171 | * immediately re-usable, it comes in the form of a delayed ref, which must be | |
1172 | * run and then the transaction must be committed. | |
1173 | * | |
1174 | * FLUSH_DELAYED_REFS | |
1175 | * The above two cases generate delayed refs that will affect | |
1176 | * ->total_bytes_pinned. However this counter can be inconsistent with | |
1177 | * reality if there are outstanding delayed refs. This is because we adjust | |
1178 | * the counter based solely on the current set of delayed refs and disregard | |
1179 | * any on-disk state which might include more refs. So for example, if we | |
1180 | * have an extent with 2 references, but we only drop 1, we'll see that there | |
1181 | * is a negative delayed ref count for the extent and assume that the space | |
1182 | * will be freed, and thus increase ->total_bytes_pinned. | |
1183 | * | |
1184 | * Running the delayed refs gives us the actual real view of what will be | |
1185 | * freed at the transaction commit time. This stage will not actually free | |
1186 | * space for us, it just makes sure that may_commit_transaction() has all of | |
1187 | * the information it needs to make the right decision. | |
1188 | * | |
1189 | * COMMIT_TRANS | |
1190 | * This is where we reclaim all of the pinned space generated by the previous | |
1191 | * two stages. We will not commit the transaction if we don't think we're | |
1192 | * likely to satisfy our request, which means if our current free space + | |
1193 | * total_bytes_pinned < reservation we will not commit. This is why the | |
1194 | * previous states are actually important, to make sure we know for sure | |
1195 | * whether committing the transaction will allow us to make progress. | |
c4923027 JB |
1196 | * |
1197 | * ALLOC_CHUNK_FORCE | |
1198 | * For data we start with alloc chunk force, however we could have been full | |
1199 | * before, and then the transaction commit could have freed new block groups, | |
1200 | * so if we now have space to allocate do the force chunk allocation. | |
1a7a92c8 | 1201 | */ |
57056740 JB |
1202 | static const enum btrfs_flush_state data_flush_states[] = { |
1203 | FLUSH_DELALLOC_WAIT, | |
1204 | RUN_DELAYED_IPUTS, | |
1205 | FLUSH_DELAYED_REFS, | |
1206 | COMMIT_TRANS, | |
c4923027 | 1207 | ALLOC_CHUNK_FORCE, |
57056740 JB |
1208 | }; |
1209 | ||
1210 | static void btrfs_async_reclaim_data_space(struct work_struct *work) | |
0d9764f6 | 1211 | { |
57056740 JB |
1212 | struct btrfs_fs_info *fs_info; |
1213 | struct btrfs_space_info *space_info; | |
1214 | u64 last_tickets_id; | |
91e79a83 | 1215 | enum btrfs_flush_state flush_state = 0; |
57056740 JB |
1216 | |
1217 | fs_info = container_of(work, struct btrfs_fs_info, async_data_reclaim_work); | |
1218 | space_info = fs_info->data_sinfo; | |
1219 | ||
1220 | spin_lock(&space_info->lock); | |
1221 | if (list_empty(&space_info->tickets)) { | |
1222 | space_info->flush = 0; | |
1223 | spin_unlock(&space_info->lock); | |
1224 | return; | |
1225 | } | |
1226 | last_tickets_id = space_info->tickets_id; | |
1227 | spin_unlock(&space_info->lock); | |
1228 | ||
1229 | while (!space_info->full) { | |
4b02b00f | 1230 | flush_space(fs_info, space_info, U64_MAX, ALLOC_CHUNK_FORCE, false); |
57056740 JB |
1231 | spin_lock(&space_info->lock); |
1232 | if (list_empty(&space_info->tickets)) { | |
1233 | space_info->flush = 0; | |
1234 | spin_unlock(&space_info->lock); | |
1235 | return; | |
1236 | } | |
1237 | last_tickets_id = space_info->tickets_id; | |
1238 | spin_unlock(&space_info->lock); | |
1239 | } | |
1240 | ||
1241 | while (flush_state < ARRAY_SIZE(data_flush_states)) { | |
1242 | flush_space(fs_info, space_info, U64_MAX, | |
4b02b00f | 1243 | data_flush_states[flush_state], false); |
57056740 JB |
1244 | spin_lock(&space_info->lock); |
1245 | if (list_empty(&space_info->tickets)) { | |
1246 | space_info->flush = 0; | |
1247 | spin_unlock(&space_info->lock); | |
1248 | return; | |
1249 | } | |
1250 | ||
1251 | if (last_tickets_id == space_info->tickets_id) { | |
1252 | flush_state++; | |
1253 | } else { | |
1254 | last_tickets_id = space_info->tickets_id; | |
1255 | flush_state = 0; | |
1256 | } | |
1257 | ||
1258 | if (flush_state >= ARRAY_SIZE(data_flush_states)) { | |
1259 | if (space_info->full) { | |
1260 | if (maybe_fail_all_tickets(fs_info, space_info)) | |
1261 | flush_state = 0; | |
1262 | else | |
1263 | space_info->flush = 0; | |
1264 | } else { | |
1265 | flush_state = 0; | |
1266 | } | |
1267 | } | |
1268 | spin_unlock(&space_info->lock); | |
1269 | } | |
1270 | } | |
1271 | ||
1272 | void btrfs_init_async_reclaim_work(struct btrfs_fs_info *fs_info) | |
1273 | { | |
1274 | INIT_WORK(&fs_info->async_reclaim_work, btrfs_async_reclaim_metadata_space); | |
1275 | INIT_WORK(&fs_info->async_data_reclaim_work, btrfs_async_reclaim_data_space); | |
576fa348 JB |
1276 | INIT_WORK(&fs_info->preempt_reclaim_work, |
1277 | btrfs_preempt_reclaim_metadata_space); | |
0d9764f6 JB |
1278 | } |
1279 | ||
1280 | static const enum btrfs_flush_state priority_flush_states[] = { | |
1281 | FLUSH_DELAYED_ITEMS_NR, | |
1282 | FLUSH_DELAYED_ITEMS, | |
1283 | ALLOC_CHUNK, | |
1284 | }; | |
1285 | ||
d3984c90 JB |
1286 | static const enum btrfs_flush_state evict_flush_states[] = { |
1287 | FLUSH_DELAYED_ITEMS_NR, | |
1288 | FLUSH_DELAYED_ITEMS, | |
1289 | FLUSH_DELAYED_REFS_NR, | |
1290 | FLUSH_DELAYED_REFS, | |
1291 | FLUSH_DELALLOC, | |
1292 | FLUSH_DELALLOC_WAIT, | |
1293 | ALLOC_CHUNK, | |
1294 | COMMIT_TRANS, | |
1295 | }; | |
1296 | ||
0d9764f6 | 1297 | static void priority_reclaim_metadata_space(struct btrfs_fs_info *fs_info, |
9ce2f423 JB |
1298 | struct btrfs_space_info *space_info, |
1299 | struct reserve_ticket *ticket, | |
1300 | const enum btrfs_flush_state *states, | |
1301 | int states_nr) | |
0d9764f6 JB |
1302 | { |
1303 | u64 to_reclaim; | |
1304 | int flush_state; | |
1305 | ||
1306 | spin_lock(&space_info->lock); | |
9f246926 | 1307 | to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info); |
0d9764f6 JB |
1308 | if (!to_reclaim) { |
1309 | spin_unlock(&space_info->lock); | |
1310 | return; | |
1311 | } | |
1312 | spin_unlock(&space_info->lock); | |
1313 | ||
1314 | flush_state = 0; | |
1315 | do { | |
4b02b00f JB |
1316 | flush_space(fs_info, space_info, to_reclaim, states[flush_state], |
1317 | false); | |
0d9764f6 JB |
1318 | flush_state++; |
1319 | spin_lock(&space_info->lock); | |
1320 | if (ticket->bytes == 0) { | |
1321 | spin_unlock(&space_info->lock); | |
1322 | return; | |
1323 | } | |
1324 | spin_unlock(&space_info->lock); | |
9ce2f423 | 1325 | } while (flush_state < states_nr); |
0d9764f6 JB |
1326 | } |
1327 | ||
1004f686 JB |
1328 | static void priority_reclaim_data_space(struct btrfs_fs_info *fs_info, |
1329 | struct btrfs_space_info *space_info, | |
57056740 | 1330 | struct reserve_ticket *ticket) |
1004f686 | 1331 | { |
1004f686 | 1332 | while (!space_info->full) { |
4b02b00f | 1333 | flush_space(fs_info, space_info, U64_MAX, ALLOC_CHUNK_FORCE, false); |
1004f686 JB |
1334 | spin_lock(&space_info->lock); |
1335 | if (ticket->bytes == 0) { | |
1336 | spin_unlock(&space_info->lock); | |
1337 | return; | |
1338 | } | |
1339 | spin_unlock(&space_info->lock); | |
1340 | } | |
1004f686 JB |
1341 | } |
1342 | ||
374bf9c5 JB |
1343 | static void wait_reserve_ticket(struct btrfs_fs_info *fs_info, |
1344 | struct btrfs_space_info *space_info, | |
1345 | struct reserve_ticket *ticket) | |
0d9764f6 JB |
1346 | |
1347 | { | |
1348 | DEFINE_WAIT(wait); | |
0d9764f6 JB |
1349 | int ret = 0; |
1350 | ||
1351 | spin_lock(&space_info->lock); | |
1352 | while (ticket->bytes > 0 && ticket->error == 0) { | |
1353 | ret = prepare_to_wait_event(&ticket->wait, &wait, TASK_KILLABLE); | |
1354 | if (ret) { | |
0cab7acc FM |
1355 | /* |
1356 | * Delete us from the list. After we unlock the space | |
1357 | * info, we don't want the async reclaim job to reserve | |
1358 | * space for this ticket. If that would happen, then the | |
1359 | * ticket's task would not known that space was reserved | |
1360 | * despite getting an error, resulting in a space leak | |
1361 | * (bytes_may_use counter of our space_info). | |
1362 | */ | |
d611add4 | 1363 | remove_ticket(space_info, ticket); |
374bf9c5 | 1364 | ticket->error = -EINTR; |
0d9764f6 JB |
1365 | break; |
1366 | } | |
1367 | spin_unlock(&space_info->lock); | |
1368 | ||
1369 | schedule(); | |
1370 | ||
1371 | finish_wait(&ticket->wait, &wait); | |
1372 | spin_lock(&space_info->lock); | |
1373 | } | |
0d9764f6 | 1374 | spin_unlock(&space_info->lock); |
0d9764f6 JB |
1375 | } |
1376 | ||
03235279 | 1377 | /** |
d98b188e NB |
1378 | * Do the appropriate flushing and waiting for a ticket |
1379 | * | |
1380 | * @fs_info: the filesystem | |
1381 | * @space_info: space info for the reservation | |
1382 | * @ticket: ticket for the reservation | |
ac1ea10e JB |
1383 | * @start_ns: timestamp when the reservation started |
1384 | * @orig_bytes: amount of bytes originally reserved | |
d98b188e | 1385 | * @flush: how much we can flush |
03235279 JB |
1386 | * |
1387 | * This does the work of figuring out how to flush for the ticket, waiting for | |
1388 | * the reservation, and returning the appropriate error if there is one. | |
1389 | */ | |
1390 | static int handle_reserve_ticket(struct btrfs_fs_info *fs_info, | |
1391 | struct btrfs_space_info *space_info, | |
1392 | struct reserve_ticket *ticket, | |
ac1ea10e | 1393 | u64 start_ns, u64 orig_bytes, |
03235279 JB |
1394 | enum btrfs_reserve_flush_enum flush) |
1395 | { | |
03235279 JB |
1396 | int ret; |
1397 | ||
d3984c90 | 1398 | switch (flush) { |
57056740 | 1399 | case BTRFS_RESERVE_FLUSH_DATA: |
d3984c90 | 1400 | case BTRFS_RESERVE_FLUSH_ALL: |
7f9fe614 | 1401 | case BTRFS_RESERVE_FLUSH_ALL_STEAL: |
03235279 | 1402 | wait_reserve_ticket(fs_info, space_info, ticket); |
d3984c90 JB |
1403 | break; |
1404 | case BTRFS_RESERVE_FLUSH_LIMIT: | |
9ce2f423 JB |
1405 | priority_reclaim_metadata_space(fs_info, space_info, ticket, |
1406 | priority_flush_states, | |
1407 | ARRAY_SIZE(priority_flush_states)); | |
d3984c90 JB |
1408 | break; |
1409 | case BTRFS_RESERVE_FLUSH_EVICT: | |
1410 | priority_reclaim_metadata_space(fs_info, space_info, ticket, | |
1411 | evict_flush_states, | |
1412 | ARRAY_SIZE(evict_flush_states)); | |
1413 | break; | |
1004f686 | 1414 | case BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE: |
57056740 | 1415 | priority_reclaim_data_space(fs_info, space_info, ticket); |
1004f686 | 1416 | break; |
d3984c90 JB |
1417 | default: |
1418 | ASSERT(0); | |
1419 | break; | |
1420 | } | |
03235279 JB |
1421 | |
1422 | spin_lock(&space_info->lock); | |
1423 | ret = ticket->error; | |
1424 | if (ticket->bytes || ticket->error) { | |
0cab7acc | 1425 | /* |
42a72cb7 JB |
1426 | * We were a priority ticket, so we need to delete ourselves |
1427 | * from the list. Because we could have other priority tickets | |
1428 | * behind us that require less space, run | |
1429 | * btrfs_try_granting_tickets() to see if their reservations can | |
1430 | * now be made. | |
0cab7acc | 1431 | */ |
42a72cb7 JB |
1432 | if (!list_empty(&ticket->list)) { |
1433 | remove_ticket(space_info, ticket); | |
1434 | btrfs_try_granting_tickets(fs_info, space_info); | |
1435 | } | |
1436 | ||
03235279 JB |
1437 | if (!ret) |
1438 | ret = -ENOSPC; | |
1439 | } | |
1440 | spin_unlock(&space_info->lock); | |
03235279 | 1441 | ASSERT(list_empty(&ticket->list)); |
0cab7acc FM |
1442 | /* |
1443 | * Check that we can't have an error set if the reservation succeeded, | |
1444 | * as that would confuse tasks and lead them to error out without | |
1445 | * releasing reserved space (if an error happens the expectation is that | |
1446 | * space wasn't reserved at all). | |
1447 | */ | |
1448 | ASSERT(!(ticket->bytes == 0 && ticket->error)); | |
ac1ea10e JB |
1449 | trace_btrfs_reserve_ticket(fs_info, space_info->flags, orig_bytes, |
1450 | start_ns, flush, ticket->error); | |
03235279 JB |
1451 | return ret; |
1452 | } | |
1453 | ||
666daa9f JB |
1454 | /* |
1455 | * This returns true if this flush state will go through the ordinary flushing | |
1456 | * code. | |
1457 | */ | |
1458 | static inline bool is_normal_flushing(enum btrfs_reserve_flush_enum flush) | |
1459 | { | |
1460 | return (flush == BTRFS_RESERVE_FLUSH_ALL) || | |
1461 | (flush == BTRFS_RESERVE_FLUSH_ALL_STEAL); | |
1462 | } | |
1463 | ||
88a777a6 JB |
1464 | static inline void maybe_clamp_preempt(struct btrfs_fs_info *fs_info, |
1465 | struct btrfs_space_info *space_info) | |
1466 | { | |
1467 | u64 ordered = percpu_counter_sum_positive(&fs_info->ordered_bytes); | |
1468 | u64 delalloc = percpu_counter_sum_positive(&fs_info->delalloc_bytes); | |
1469 | ||
1470 | /* | |
1471 | * If we're heavy on ordered operations then clamping won't help us. We | |
1472 | * need to clamp specifically to keep up with dirty'ing buffered | |
1473 | * writers, because there's not a 1:1 correlation of writing delalloc | |
1474 | * and freeing space, like there is with flushing delayed refs or | |
1475 | * delayed nodes. If we're already more ordered than delalloc then | |
1476 | * we're keeping up, otherwise we aren't and should probably clamp. | |
1477 | */ | |
1478 | if (ordered < delalloc) | |
1479 | space_info->clamp = min(space_info->clamp + 1, 8); | |
1480 | } | |
1481 | ||
0d9764f6 | 1482 | /** |
d98b188e NB |
1483 | * Try to reserve bytes from the block_rsv's space |
1484 | * | |
1485 | * @fs_info: the filesystem | |
1486 | * @space_info: space info we want to allocate from | |
1487 | * @orig_bytes: number of bytes we want | |
1488 | * @flush: whether or not we can flush to make our reservation | |
0d9764f6 JB |
1489 | * |
1490 | * This will reserve orig_bytes number of bytes from the space info associated | |
1491 | * with the block_rsv. If there is not enough space it will make an attempt to | |
1492 | * flush out space to make room. It will do this by flushing delalloc if | |
1493 | * possible or committing the transaction. If flush is 0 then no attempts to | |
1494 | * regain reservations will be made and this will fail if there is not enough | |
1495 | * space already. | |
1496 | */ | |
f3bda421 JB |
1497 | static int __reserve_bytes(struct btrfs_fs_info *fs_info, |
1498 | struct btrfs_space_info *space_info, u64 orig_bytes, | |
1499 | enum btrfs_reserve_flush_enum flush) | |
0d9764f6 | 1500 | { |
57056740 | 1501 | struct work_struct *async_work; |
0d9764f6 | 1502 | struct reserve_ticket ticket; |
ac1ea10e | 1503 | u64 start_ns = 0; |
0d9764f6 | 1504 | u64 used; |
0d9764f6 | 1505 | int ret = 0; |
ef1317a1 | 1506 | bool pending_tickets; |
0d9764f6 JB |
1507 | |
1508 | ASSERT(orig_bytes); | |
1509 | ASSERT(!current->journal_info || flush != BTRFS_RESERVE_FLUSH_ALL); | |
1510 | ||
57056740 JB |
1511 | if (flush == BTRFS_RESERVE_FLUSH_DATA) |
1512 | async_work = &fs_info->async_data_reclaim_work; | |
1513 | else | |
1514 | async_work = &fs_info->async_reclaim_work; | |
1515 | ||
0d9764f6 JB |
1516 | spin_lock(&space_info->lock); |
1517 | ret = -ENOSPC; | |
1518 | used = btrfs_space_info_used(space_info, true); | |
666daa9f JB |
1519 | |
1520 | /* | |
1521 | * We don't want NO_FLUSH allocations to jump everybody, they can | |
1522 | * generally handle ENOSPC in a different way, so treat them the same as | |
1523 | * normal flushers when it comes to skipping pending tickets. | |
1524 | */ | |
1525 | if (is_normal_flushing(flush) || (flush == BTRFS_RESERVE_NO_FLUSH)) | |
1526 | pending_tickets = !list_empty(&space_info->tickets) || | |
1527 | !list_empty(&space_info->priority_tickets); | |
1528 | else | |
1529 | pending_tickets = !list_empty(&space_info->priority_tickets); | |
0d9764f6 JB |
1530 | |
1531 | /* | |
9b4851bc GR |
1532 | * Carry on if we have enough space (short-circuit) OR call |
1533 | * can_overcommit() to ensure we can overcommit to continue. | |
0d9764f6 | 1534 | */ |
ef1317a1 JB |
1535 | if (!pending_tickets && |
1536 | ((used + orig_bytes <= space_info->total_bytes) || | |
a30a3d20 | 1537 | btrfs_can_overcommit(fs_info, space_info, orig_bytes, flush))) { |
0d9764f6 JB |
1538 | btrfs_space_info_update_bytes_may_use(fs_info, space_info, |
1539 | orig_bytes); | |
0d9764f6 JB |
1540 | ret = 0; |
1541 | } | |
1542 | ||
1543 | /* | |
1544 | * If we couldn't make a reservation then setup our reservation ticket | |
1545 | * and kick the async worker if it's not already running. | |
1546 | * | |
1547 | * If we are a priority flusher then we just need to add our ticket to | |
1548 | * the list and we will do our own flushing further down. | |
1549 | */ | |
1550 | if (ret && flush != BTRFS_RESERVE_NO_FLUSH) { | |
0d9764f6 JB |
1551 | ticket.bytes = orig_bytes; |
1552 | ticket.error = 0; | |
db161806 | 1553 | space_info->reclaim_size += ticket.bytes; |
0d9764f6 | 1554 | init_waitqueue_head(&ticket.wait); |
7f9fe614 | 1555 | ticket.steal = (flush == BTRFS_RESERVE_FLUSH_ALL_STEAL); |
ac1ea10e JB |
1556 | if (trace_btrfs_reserve_ticket_enabled()) |
1557 | start_ns = ktime_get_ns(); | |
1558 | ||
7f9fe614 | 1559 | if (flush == BTRFS_RESERVE_FLUSH_ALL || |
57056740 JB |
1560 | flush == BTRFS_RESERVE_FLUSH_ALL_STEAL || |
1561 | flush == BTRFS_RESERVE_FLUSH_DATA) { | |
0d9764f6 JB |
1562 | list_add_tail(&ticket.list, &space_info->tickets); |
1563 | if (!space_info->flush) { | |
1564 | space_info->flush = 1; | |
1565 | trace_btrfs_trigger_flush(fs_info, | |
1566 | space_info->flags, | |
1567 | orig_bytes, flush, | |
1568 | "enospc"); | |
57056740 | 1569 | queue_work(system_unbound_wq, async_work); |
0d9764f6 JB |
1570 | } |
1571 | } else { | |
1572 | list_add_tail(&ticket.list, | |
1573 | &space_info->priority_tickets); | |
1574 | } | |
88a777a6 JB |
1575 | |
1576 | /* | |
1577 | * We were forced to add a reserve ticket, so our preemptive | |
1578 | * flushing is unable to keep up. Clamp down on the threshold | |
1579 | * for the preemptive flushing in order to keep up with the | |
1580 | * workload. | |
1581 | */ | |
1582 | maybe_clamp_preempt(fs_info, space_info); | |
0d9764f6 JB |
1583 | } else if (!ret && space_info->flags & BTRFS_BLOCK_GROUP_METADATA) { |
1584 | used += orig_bytes; | |
1585 | /* | |
1586 | * We will do the space reservation dance during log replay, | |
1587 | * which means we won't have fs_info->fs_root set, so don't do | |
1588 | * the async reclaim as we will panic. | |
1589 | */ | |
1590 | if (!test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags) && | |
2e294c60 | 1591 | need_preemptive_reclaim(fs_info, space_info) && |
576fa348 | 1592 | !work_busy(&fs_info->preempt_reclaim_work)) { |
0d9764f6 JB |
1593 | trace_btrfs_trigger_flush(fs_info, space_info->flags, |
1594 | orig_bytes, flush, "preempt"); | |
1595 | queue_work(system_unbound_wq, | |
576fa348 | 1596 | &fs_info->preempt_reclaim_work); |
0d9764f6 JB |
1597 | } |
1598 | } | |
1599 | spin_unlock(&space_info->lock); | |
1600 | if (!ret || flush == BTRFS_RESERVE_NO_FLUSH) | |
1601 | return ret; | |
1602 | ||
ac1ea10e JB |
1603 | return handle_reserve_ticket(fs_info, space_info, &ticket, start_ns, |
1604 | orig_bytes, flush); | |
0d9764f6 JB |
1605 | } |
1606 | ||
1607 | /** | |
d98b188e NB |
1608 | * Trye to reserve metadata bytes from the block_rsv's space |
1609 | * | |
1610 | * @root: the root we're allocating for | |
1611 | * @block_rsv: block_rsv we're allocating for | |
1612 | * @orig_bytes: number of bytes we want | |
1613 | * @flush: whether or not we can flush to make our reservation | |
0d9764f6 JB |
1614 | * |
1615 | * This will reserve orig_bytes number of bytes from the space info associated | |
1616 | * with the block_rsv. If there is not enough space it will make an attempt to | |
1617 | * flush out space to make room. It will do this by flushing delalloc if | |
1618 | * possible or committing the transaction. If flush is 0 then no attempts to | |
1619 | * regain reservations will be made and this will fail if there is not enough | |
1620 | * space already. | |
1621 | */ | |
1622 | int btrfs_reserve_metadata_bytes(struct btrfs_root *root, | |
1623 | struct btrfs_block_rsv *block_rsv, | |
1624 | u64 orig_bytes, | |
1625 | enum btrfs_reserve_flush_enum flush) | |
1626 | { | |
1627 | struct btrfs_fs_info *fs_info = root->fs_info; | |
1628 | struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv; | |
1629 | int ret; | |
0d9764f6 | 1630 | |
f3bda421 | 1631 | ret = __reserve_bytes(fs_info, block_rsv->space_info, orig_bytes, flush); |
0d9764f6 JB |
1632 | if (ret == -ENOSPC && |
1633 | unlikely(root->orphan_cleanup_state == ORPHAN_CLEANUP_STARTED)) { | |
1634 | if (block_rsv != global_rsv && | |
1635 | !btrfs_block_rsv_use_bytes(global_rsv, orig_bytes)) | |
1636 | ret = 0; | |
1637 | } | |
1638 | if (ret == -ENOSPC) { | |
1639 | trace_btrfs_space_reservation(fs_info, "space_info:enospc", | |
1640 | block_rsv->space_info->flags, | |
1641 | orig_bytes, 1); | |
1642 | ||
1643 | if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) | |
1644 | btrfs_dump_space_info(fs_info, block_rsv->space_info, | |
1645 | orig_bytes, 0); | |
1646 | } | |
1647 | return ret; | |
1648 | } | |
8698fc4e JB |
1649 | |
1650 | /** | |
d98b188e NB |
1651 | * Try to reserve data bytes for an allocation |
1652 | * | |
1653 | * @fs_info: the filesystem | |
1654 | * @bytes: number of bytes we need | |
1655 | * @flush: how we are allowed to flush | |
8698fc4e JB |
1656 | * |
1657 | * This will reserve bytes from the data space info. If there is not enough | |
1658 | * space then we will attempt to flush space as specified by flush. | |
1659 | */ | |
1660 | int btrfs_reserve_data_bytes(struct btrfs_fs_info *fs_info, u64 bytes, | |
1661 | enum btrfs_reserve_flush_enum flush) | |
1662 | { | |
1663 | struct btrfs_space_info *data_sinfo = fs_info->data_sinfo; | |
f3bda421 | 1664 | int ret; |
8698fc4e | 1665 | |
f3bda421 JB |
1666 | ASSERT(flush == BTRFS_RESERVE_FLUSH_DATA || |
1667 | flush == BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE); | |
8698fc4e JB |
1668 | ASSERT(!current->journal_info || flush != BTRFS_RESERVE_FLUSH_DATA); |
1669 | ||
f3bda421 JB |
1670 | ret = __reserve_bytes(fs_info, data_sinfo, bytes, flush); |
1671 | if (ret == -ENOSPC) { | |
1672 | trace_btrfs_space_reservation(fs_info, "space_info:enospc", | |
8698fc4e | 1673 | data_sinfo->flags, bytes, 1); |
f3bda421 JB |
1674 | if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) |
1675 | btrfs_dump_space_info(fs_info, data_sinfo, bytes, 0); | |
1676 | } | |
8698fc4e JB |
1677 | return ret; |
1678 | } |