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efc27b52 DC |
1 | /* |
2 | * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc. | |
3 | * Copyright (c) 2010 David Chinner. | |
4 | * Copyright (c) 2011 Christoph Hellwig. | |
5 | * All Rights Reserved. | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or | |
8 | * modify it under the terms of the GNU General Public License as | |
9 | * published by the Free Software Foundation. | |
10 | * | |
11 | * This program is distributed in the hope that it would be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program; if not, write the Free Software Foundation, | |
18 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
19 | */ | |
20 | #include "xfs.h" | |
21 | #include "xfs_fs.h" | |
70a9883c DC |
22 | #include "xfs_format.h" |
23 | #include "xfs_shared.h" | |
efc27b52 DC |
24 | #include "xfs_log.h" |
25 | #include "xfs_trans.h" | |
26 | #include "xfs_sb.h" | |
27 | #include "xfs_ag.h" | |
28 | #include "xfs_mount.h" | |
29 | #include "xfs_bmap_btree.h" | |
30 | #include "xfs_alloc.h" | |
31 | #include "xfs_inode.h" | |
32 | #include "xfs_extent_busy.h" | |
33 | #include "xfs_trace.h" | |
34 | ||
35 | void | |
4ecbfe63 | 36 | xfs_extent_busy_insert( |
efc27b52 DC |
37 | struct xfs_trans *tp, |
38 | xfs_agnumber_t agno, | |
39 | xfs_agblock_t bno, | |
40 | xfs_extlen_t len, | |
41 | unsigned int flags) | |
42 | { | |
4ecbfe63 DC |
43 | struct xfs_extent_busy *new; |
44 | struct xfs_extent_busy *busyp; | |
efc27b52 DC |
45 | struct xfs_perag *pag; |
46 | struct rb_node **rbp; | |
47 | struct rb_node *parent = NULL; | |
48 | ||
4ecbfe63 | 49 | new = kmem_zalloc(sizeof(struct xfs_extent_busy), KM_MAYFAIL); |
efc27b52 DC |
50 | if (!new) { |
51 | /* | |
52 | * No Memory! Since it is now not possible to track the free | |
53 | * block, make this a synchronous transaction to insure that | |
54 | * the block is not reused before this transaction commits. | |
55 | */ | |
4ecbfe63 | 56 | trace_xfs_extent_busy_enomem(tp->t_mountp, agno, bno, len); |
efc27b52 DC |
57 | xfs_trans_set_sync(tp); |
58 | return; | |
59 | } | |
60 | ||
61 | new->agno = agno; | |
62 | new->bno = bno; | |
63 | new->length = len; | |
64 | INIT_LIST_HEAD(&new->list); | |
65 | new->flags = flags; | |
66 | ||
67 | /* trace before insert to be able to see failed inserts */ | |
4ecbfe63 | 68 | trace_xfs_extent_busy(tp->t_mountp, agno, bno, len); |
efc27b52 DC |
69 | |
70 | pag = xfs_perag_get(tp->t_mountp, new->agno); | |
71 | spin_lock(&pag->pagb_lock); | |
72 | rbp = &pag->pagb_tree.rb_node; | |
73 | while (*rbp) { | |
74 | parent = *rbp; | |
4ecbfe63 | 75 | busyp = rb_entry(parent, struct xfs_extent_busy, rb_node); |
efc27b52 DC |
76 | |
77 | if (new->bno < busyp->bno) { | |
78 | rbp = &(*rbp)->rb_left; | |
79 | ASSERT(new->bno + new->length <= busyp->bno); | |
80 | } else if (new->bno > busyp->bno) { | |
81 | rbp = &(*rbp)->rb_right; | |
82 | ASSERT(bno >= busyp->bno + busyp->length); | |
83 | } else { | |
84 | ASSERT(0); | |
85 | } | |
86 | } | |
87 | ||
88 | rb_link_node(&new->rb_node, parent, rbp); | |
89 | rb_insert_color(&new->rb_node, &pag->pagb_tree); | |
90 | ||
91 | list_add(&new->list, &tp->t_busy); | |
92 | spin_unlock(&pag->pagb_lock); | |
93 | xfs_perag_put(pag); | |
94 | } | |
95 | ||
96 | /* | |
97 | * Search for a busy extent within the range of the extent we are about to | |
98 | * allocate. You need to be holding the busy extent tree lock when calling | |
4ecbfe63 | 99 | * xfs_extent_busy_search(). This function returns 0 for no overlapping busy |
efc27b52 DC |
100 | * extent, -1 for an overlapping but not exact busy extent, and 1 for an exact |
101 | * match. This is done so that a non-zero return indicates an overlap that | |
102 | * will require a synchronous transaction, but it can still be | |
103 | * used to distinguish between a partial or exact match. | |
104 | */ | |
105 | int | |
4ecbfe63 | 106 | xfs_extent_busy_search( |
efc27b52 DC |
107 | struct xfs_mount *mp, |
108 | xfs_agnumber_t agno, | |
109 | xfs_agblock_t bno, | |
110 | xfs_extlen_t len) | |
111 | { | |
112 | struct xfs_perag *pag; | |
113 | struct rb_node *rbp; | |
4ecbfe63 | 114 | struct xfs_extent_busy *busyp; |
efc27b52 DC |
115 | int match = 0; |
116 | ||
117 | pag = xfs_perag_get(mp, agno); | |
118 | spin_lock(&pag->pagb_lock); | |
119 | ||
120 | rbp = pag->pagb_tree.rb_node; | |
121 | ||
122 | /* find closest start bno overlap */ | |
123 | while (rbp) { | |
4ecbfe63 | 124 | busyp = rb_entry(rbp, struct xfs_extent_busy, rb_node); |
efc27b52 DC |
125 | if (bno < busyp->bno) { |
126 | /* may overlap, but exact start block is lower */ | |
127 | if (bno + len > busyp->bno) | |
128 | match = -1; | |
129 | rbp = rbp->rb_left; | |
130 | } else if (bno > busyp->bno) { | |
131 | /* may overlap, but exact start block is higher */ | |
132 | if (bno < busyp->bno + busyp->length) | |
133 | match = -1; | |
134 | rbp = rbp->rb_right; | |
135 | } else { | |
136 | /* bno matches busyp, length determines exact match */ | |
137 | match = (busyp->length == len) ? 1 : -1; | |
138 | break; | |
139 | } | |
140 | } | |
141 | spin_unlock(&pag->pagb_lock); | |
142 | xfs_perag_put(pag); | |
143 | return match; | |
144 | } | |
145 | ||
146 | /* | |
147 | * The found free extent [fbno, fend] overlaps part or all of the given busy | |
148 | * extent. If the overlap covers the beginning, the end, or all of the busy | |
149 | * extent, the overlapping portion can be made unbusy and used for the | |
150 | * allocation. We can't split a busy extent because we can't modify a | |
b3c49634 | 151 | * transaction/CIL context busy list, but we can update an entry's block |
efc27b52 DC |
152 | * number or length. |
153 | * | |
154 | * Returns true if the extent can safely be reused, or false if the search | |
155 | * needs to be restarted. | |
156 | */ | |
157 | STATIC bool | |
4ecbfe63 | 158 | xfs_extent_busy_update_extent( |
efc27b52 DC |
159 | struct xfs_mount *mp, |
160 | struct xfs_perag *pag, | |
4ecbfe63 | 161 | struct xfs_extent_busy *busyp, |
efc27b52 DC |
162 | xfs_agblock_t fbno, |
163 | xfs_extlen_t flen, | |
a30b0367 DC |
164 | bool userdata) __releases(&pag->pagb_lock) |
165 | __acquires(&pag->pagb_lock) | |
efc27b52 DC |
166 | { |
167 | xfs_agblock_t fend = fbno + flen; | |
168 | xfs_agblock_t bbno = busyp->bno; | |
169 | xfs_agblock_t bend = bbno + busyp->length; | |
170 | ||
171 | /* | |
172 | * This extent is currently being discarded. Give the thread | |
173 | * performing the discard a chance to mark the extent unbusy | |
174 | * and retry. | |
175 | */ | |
4ecbfe63 | 176 | if (busyp->flags & XFS_EXTENT_BUSY_DISCARDED) { |
efc27b52 DC |
177 | spin_unlock(&pag->pagb_lock); |
178 | delay(1); | |
179 | spin_lock(&pag->pagb_lock); | |
180 | return false; | |
181 | } | |
182 | ||
183 | /* | |
184 | * If there is a busy extent overlapping a user allocation, we have | |
185 | * no choice but to force the log and retry the search. | |
186 | * | |
187 | * Fortunately this does not happen during normal operation, but | |
188 | * only if the filesystem is very low on space and has to dip into | |
189 | * the AGFL for normal allocations. | |
190 | */ | |
191 | if (userdata) | |
192 | goto out_force_log; | |
193 | ||
194 | if (bbno < fbno && bend > fend) { | |
195 | /* | |
196 | * Case 1: | |
197 | * bbno bend | |
198 | * +BBBBBBBBBBBBBBBBB+ | |
199 | * +---------+ | |
200 | * fbno fend | |
201 | */ | |
202 | ||
203 | /* | |
204 | * We would have to split the busy extent to be able to track | |
205 | * it correct, which we cannot do because we would have to | |
206 | * modify the list of busy extents attached to the transaction | |
207 | * or CIL context, which is immutable. | |
208 | * | |
209 | * Force out the log to clear the busy extent and retry the | |
210 | * search. | |
211 | */ | |
212 | goto out_force_log; | |
213 | } else if (bbno >= fbno && bend <= fend) { | |
214 | /* | |
215 | * Case 2: | |
216 | * bbno bend | |
217 | * +BBBBBBBBBBBBBBBBB+ | |
218 | * +-----------------+ | |
219 | * fbno fend | |
220 | * | |
221 | * Case 3: | |
222 | * bbno bend | |
223 | * +BBBBBBBBBBBBBBBBB+ | |
224 | * +--------------------------+ | |
225 | * fbno fend | |
226 | * | |
227 | * Case 4: | |
228 | * bbno bend | |
229 | * +BBBBBBBBBBBBBBBBB+ | |
230 | * +--------------------------+ | |
231 | * fbno fend | |
232 | * | |
233 | * Case 5: | |
234 | * bbno bend | |
235 | * +BBBBBBBBBBBBBBBBB+ | |
236 | * +-----------------------------------+ | |
237 | * fbno fend | |
238 | * | |
239 | */ | |
240 | ||
241 | /* | |
242 | * The busy extent is fully covered by the extent we are | |
243 | * allocating, and can simply be removed from the rbtree. | |
244 | * However we cannot remove it from the immutable list | |
245 | * tracking busy extents in the transaction or CIL context, | |
246 | * so set the length to zero to mark it invalid. | |
247 | * | |
248 | * We also need to restart the busy extent search from the | |
249 | * tree root, because erasing the node can rearrange the | |
250 | * tree topology. | |
251 | */ | |
252 | rb_erase(&busyp->rb_node, &pag->pagb_tree); | |
253 | busyp->length = 0; | |
254 | return false; | |
255 | } else if (fend < bend) { | |
256 | /* | |
257 | * Case 6: | |
258 | * bbno bend | |
259 | * +BBBBBBBBBBBBBBBBB+ | |
260 | * +---------+ | |
261 | * fbno fend | |
262 | * | |
263 | * Case 7: | |
264 | * bbno bend | |
265 | * +BBBBBBBBBBBBBBBBB+ | |
266 | * +------------------+ | |
267 | * fbno fend | |
268 | * | |
269 | */ | |
270 | busyp->bno = fend; | |
271 | } else if (bbno < fbno) { | |
272 | /* | |
273 | * Case 8: | |
274 | * bbno bend | |
275 | * +BBBBBBBBBBBBBBBBB+ | |
276 | * +-------------+ | |
277 | * fbno fend | |
278 | * | |
279 | * Case 9: | |
280 | * bbno bend | |
281 | * +BBBBBBBBBBBBBBBBB+ | |
282 | * +----------------------+ | |
283 | * fbno fend | |
284 | */ | |
285 | busyp->length = fbno - busyp->bno; | |
286 | } else { | |
287 | ASSERT(0); | |
288 | } | |
289 | ||
4ecbfe63 | 290 | trace_xfs_extent_busy_reuse(mp, pag->pag_agno, fbno, flen); |
efc27b52 DC |
291 | return true; |
292 | ||
293 | out_force_log: | |
294 | spin_unlock(&pag->pagb_lock); | |
295 | xfs_log_force(mp, XFS_LOG_SYNC); | |
4ecbfe63 | 296 | trace_xfs_extent_busy_force(mp, pag->pag_agno, fbno, flen); |
efc27b52 DC |
297 | spin_lock(&pag->pagb_lock); |
298 | return false; | |
299 | } | |
300 | ||
301 | ||
302 | /* | |
303 | * For a given extent [fbno, flen], make sure we can reuse it safely. | |
304 | */ | |
305 | void | |
4ecbfe63 | 306 | xfs_extent_busy_reuse( |
efc27b52 DC |
307 | struct xfs_mount *mp, |
308 | xfs_agnumber_t agno, | |
309 | xfs_agblock_t fbno, | |
310 | xfs_extlen_t flen, | |
311 | bool userdata) | |
312 | { | |
313 | struct xfs_perag *pag; | |
314 | struct rb_node *rbp; | |
315 | ||
316 | ASSERT(flen > 0); | |
317 | ||
318 | pag = xfs_perag_get(mp, agno); | |
319 | spin_lock(&pag->pagb_lock); | |
320 | restart: | |
321 | rbp = pag->pagb_tree.rb_node; | |
322 | while (rbp) { | |
4ecbfe63 DC |
323 | struct xfs_extent_busy *busyp = |
324 | rb_entry(rbp, struct xfs_extent_busy, rb_node); | |
efc27b52 DC |
325 | xfs_agblock_t bbno = busyp->bno; |
326 | xfs_agblock_t bend = bbno + busyp->length; | |
327 | ||
328 | if (fbno + flen <= bbno) { | |
329 | rbp = rbp->rb_left; | |
330 | continue; | |
331 | } else if (fbno >= bend) { | |
332 | rbp = rbp->rb_right; | |
333 | continue; | |
334 | } | |
335 | ||
4ecbfe63 | 336 | if (!xfs_extent_busy_update_extent(mp, pag, busyp, fbno, flen, |
efc27b52 DC |
337 | userdata)) |
338 | goto restart; | |
339 | } | |
340 | spin_unlock(&pag->pagb_lock); | |
341 | xfs_perag_put(pag); | |
342 | } | |
343 | ||
344 | /* | |
345 | * For a given extent [fbno, flen], search the busy extent list to find a | |
346 | * subset of the extent that is not busy. If *rlen is smaller than | |
347 | * args->minlen no suitable extent could be found, and the higher level | |
348 | * code needs to force out the log and retry the allocation. | |
349 | */ | |
e700a06c | 350 | void |
4ecbfe63 | 351 | xfs_extent_busy_trim( |
efc27b52 DC |
352 | struct xfs_alloc_arg *args, |
353 | xfs_agblock_t bno, | |
354 | xfs_extlen_t len, | |
355 | xfs_agblock_t *rbno, | |
356 | xfs_extlen_t *rlen) | |
357 | { | |
358 | xfs_agblock_t fbno; | |
359 | xfs_extlen_t flen; | |
360 | struct rb_node *rbp; | |
361 | ||
362 | ASSERT(len > 0); | |
363 | ||
364 | spin_lock(&args->pag->pagb_lock); | |
365 | restart: | |
366 | fbno = bno; | |
367 | flen = len; | |
368 | rbp = args->pag->pagb_tree.rb_node; | |
369 | while (rbp && flen >= args->minlen) { | |
4ecbfe63 DC |
370 | struct xfs_extent_busy *busyp = |
371 | rb_entry(rbp, struct xfs_extent_busy, rb_node); | |
efc27b52 DC |
372 | xfs_agblock_t fend = fbno + flen; |
373 | xfs_agblock_t bbno = busyp->bno; | |
374 | xfs_agblock_t bend = bbno + busyp->length; | |
375 | ||
376 | if (fend <= bbno) { | |
377 | rbp = rbp->rb_left; | |
378 | continue; | |
379 | } else if (fbno >= bend) { | |
380 | rbp = rbp->rb_right; | |
381 | continue; | |
382 | } | |
383 | ||
384 | /* | |
385 | * If this is a metadata allocation, try to reuse the busy | |
386 | * extent instead of trimming the allocation. | |
387 | */ | |
388 | if (!args->userdata && | |
4ecbfe63 DC |
389 | !(busyp->flags & XFS_EXTENT_BUSY_DISCARDED)) { |
390 | if (!xfs_extent_busy_update_extent(args->mp, args->pag, | |
efc27b52 DC |
391 | busyp, fbno, flen, |
392 | false)) | |
393 | goto restart; | |
394 | continue; | |
395 | } | |
396 | ||
397 | if (bbno <= fbno) { | |
398 | /* start overlap */ | |
399 | ||
400 | /* | |
401 | * Case 1: | |
402 | * bbno bend | |
403 | * +BBBBBBBBBBBBBBBBB+ | |
404 | * +---------+ | |
405 | * fbno fend | |
406 | * | |
407 | * Case 2: | |
408 | * bbno bend | |
409 | * +BBBBBBBBBBBBBBBBB+ | |
410 | * +-------------+ | |
411 | * fbno fend | |
412 | * | |
413 | * Case 3: | |
414 | * bbno bend | |
415 | * +BBBBBBBBBBBBBBBBB+ | |
416 | * +-------------+ | |
417 | * fbno fend | |
418 | * | |
419 | * Case 4: | |
420 | * bbno bend | |
421 | * +BBBBBBBBBBBBBBBBB+ | |
422 | * +-----------------+ | |
423 | * fbno fend | |
424 | * | |
425 | * No unbusy region in extent, return failure. | |
426 | */ | |
427 | if (fend <= bend) | |
428 | goto fail; | |
429 | ||
430 | /* | |
431 | * Case 5: | |
432 | * bbno bend | |
433 | * +BBBBBBBBBBBBBBBBB+ | |
434 | * +----------------------+ | |
435 | * fbno fend | |
436 | * | |
437 | * Case 6: | |
438 | * bbno bend | |
439 | * +BBBBBBBBBBBBBBBBB+ | |
440 | * +--------------------------+ | |
441 | * fbno fend | |
442 | * | |
443 | * Needs to be trimmed to: | |
444 | * +-------+ | |
445 | * fbno fend | |
446 | */ | |
447 | fbno = bend; | |
448 | } else if (bend >= fend) { | |
449 | /* end overlap */ | |
450 | ||
451 | /* | |
452 | * Case 7: | |
453 | * bbno bend | |
454 | * +BBBBBBBBBBBBBBBBB+ | |
455 | * +------------------+ | |
456 | * fbno fend | |
457 | * | |
458 | * Case 8: | |
459 | * bbno bend | |
460 | * +BBBBBBBBBBBBBBBBB+ | |
461 | * +--------------------------+ | |
462 | * fbno fend | |
463 | * | |
464 | * Needs to be trimmed to: | |
465 | * +-------+ | |
466 | * fbno fend | |
467 | */ | |
468 | fend = bbno; | |
469 | } else { | |
470 | /* middle overlap */ | |
471 | ||
472 | /* | |
473 | * Case 9: | |
474 | * bbno bend | |
475 | * +BBBBBBBBBBBBBBBBB+ | |
476 | * +-----------------------------------+ | |
477 | * fbno fend | |
478 | * | |
479 | * Can be trimmed to: | |
480 | * +-------+ OR +-------+ | |
481 | * fbno fend fbno fend | |
482 | * | |
483 | * Backward allocation leads to significant | |
484 | * fragmentation of directories, which degrades | |
485 | * directory performance, therefore we always want to | |
486 | * choose the option that produces forward allocation | |
487 | * patterns. | |
488 | * Preferring the lower bno extent will make the next | |
489 | * request use "fend" as the start of the next | |
490 | * allocation; if the segment is no longer busy at | |
491 | * that point, we'll get a contiguous allocation, but | |
492 | * even if it is still busy, we will get a forward | |
493 | * allocation. | |
494 | * We try to avoid choosing the segment at "bend", | |
495 | * because that can lead to the next allocation | |
496 | * taking the segment at "fbno", which would be a | |
497 | * backward allocation. We only use the segment at | |
498 | * "fbno" if it is much larger than the current | |
499 | * requested size, because in that case there's a | |
500 | * good chance subsequent allocations will be | |
501 | * contiguous. | |
502 | */ | |
503 | if (bbno - fbno >= args->maxlen) { | |
504 | /* left candidate fits perfect */ | |
505 | fend = bbno; | |
506 | } else if (fend - bend >= args->maxlen * 4) { | |
507 | /* right candidate has enough free space */ | |
508 | fbno = bend; | |
509 | } else if (bbno - fbno >= args->minlen) { | |
510 | /* left candidate fits minimum requirement */ | |
511 | fend = bbno; | |
512 | } else { | |
513 | goto fail; | |
514 | } | |
515 | } | |
516 | ||
517 | flen = fend - fbno; | |
518 | } | |
519 | spin_unlock(&args->pag->pagb_lock); | |
520 | ||
521 | if (fbno != bno || flen != len) { | |
4ecbfe63 | 522 | trace_xfs_extent_busy_trim(args->mp, args->agno, bno, len, |
efc27b52 DC |
523 | fbno, flen); |
524 | } | |
525 | *rbno = fbno; | |
526 | *rlen = flen; | |
527 | return; | |
528 | fail: | |
529 | /* | |
530 | * Return a zero extent length as failure indications. All callers | |
531 | * re-check if the trimmed extent satisfies the minlen requirement. | |
532 | */ | |
533 | spin_unlock(&args->pag->pagb_lock); | |
4ecbfe63 | 534 | trace_xfs_extent_busy_trim(args->mp, args->agno, bno, len, fbno, 0); |
efc27b52 DC |
535 | *rbno = fbno; |
536 | *rlen = 0; | |
537 | } | |
538 | ||
4ecbfe63 DC |
539 | STATIC void |
540 | xfs_extent_busy_clear_one( | |
efc27b52 DC |
541 | struct xfs_mount *mp, |
542 | struct xfs_perag *pag, | |
4ecbfe63 | 543 | struct xfs_extent_busy *busyp) |
efc27b52 DC |
544 | { |
545 | if (busyp->length) { | |
4ecbfe63 | 546 | trace_xfs_extent_busy_clear(mp, busyp->agno, busyp->bno, |
efc27b52 DC |
547 | busyp->length); |
548 | rb_erase(&busyp->rb_node, &pag->pagb_tree); | |
549 | } | |
550 | ||
551 | list_del_init(&busyp->list); | |
552 | kmem_free(busyp); | |
553 | } | |
554 | ||
555 | /* | |
556 | * Remove all extents on the passed in list from the busy extents tree. | |
557 | * If do_discard is set skip extents that need to be discarded, and mark | |
558 | * these as undergoing a discard operation instead. | |
559 | */ | |
560 | void | |
4ecbfe63 | 561 | xfs_extent_busy_clear( |
efc27b52 DC |
562 | struct xfs_mount *mp, |
563 | struct list_head *list, | |
564 | bool do_discard) | |
565 | { | |
4ecbfe63 | 566 | struct xfs_extent_busy *busyp, *n; |
efc27b52 DC |
567 | struct xfs_perag *pag = NULL; |
568 | xfs_agnumber_t agno = NULLAGNUMBER; | |
569 | ||
570 | list_for_each_entry_safe(busyp, n, list, list) { | |
571 | if (busyp->agno != agno) { | |
572 | if (pag) { | |
573 | spin_unlock(&pag->pagb_lock); | |
574 | xfs_perag_put(pag); | |
575 | } | |
576 | pag = xfs_perag_get(mp, busyp->agno); | |
577 | spin_lock(&pag->pagb_lock); | |
578 | agno = busyp->agno; | |
579 | } | |
580 | ||
581 | if (do_discard && busyp->length && | |
4ecbfe63 DC |
582 | !(busyp->flags & XFS_EXTENT_BUSY_SKIP_DISCARD)) |
583 | busyp->flags = XFS_EXTENT_BUSY_DISCARDED; | |
efc27b52 | 584 | else |
4ecbfe63 | 585 | xfs_extent_busy_clear_one(mp, pag, busyp); |
efc27b52 DC |
586 | } |
587 | ||
588 | if (pag) { | |
589 | spin_unlock(&pag->pagb_lock); | |
590 | xfs_perag_put(pag); | |
591 | } | |
592 | } | |
593 | ||
594 | /* | |
595 | * Callback for list_sort to sort busy extents by the AG they reside in. | |
596 | */ | |
597 | int | |
4ecbfe63 | 598 | xfs_extent_busy_ag_cmp( |
efc27b52 DC |
599 | void *priv, |
600 | struct list_head *a, | |
601 | struct list_head *b) | |
602 | { | |
4ecbfe63 DC |
603 | return container_of(a, struct xfs_extent_busy, list)->agno - |
604 | container_of(b, struct xfs_extent_busy, list)->agno; | |
efc27b52 | 605 | } |