Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
7b718769 | 2 | * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc. |
c7e8f268 | 3 | * Copyright (c) 2008 Dave Chinner |
7b718769 | 4 | * All Rights Reserved. |
1da177e4 | 5 | * |
7b718769 NS |
6 | * This program is free software; you can redistribute it and/or |
7 | * modify it under the terms of the GNU General Public License as | |
1da177e4 LT |
8 | * published by the Free Software Foundation. |
9 | * | |
7b718769 NS |
10 | * This program is distributed in the hope that it would be useful, |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU General Public License for more details. | |
1da177e4 | 14 | * |
7b718769 NS |
15 | * You should have received a copy of the GNU General Public License |
16 | * along with this program; if not, write the Free Software Foundation, | |
17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
1da177e4 | 18 | */ |
1da177e4 | 19 | #include "xfs.h" |
a844f451 | 20 | #include "xfs_fs.h" |
4fb6e8ad | 21 | #include "xfs_format.h" |
239880ef DC |
22 | #include "xfs_log_format.h" |
23 | #include "xfs_trans_resv.h" | |
1da177e4 | 24 | #include "xfs_mount.h" |
239880ef | 25 | #include "xfs_trans.h" |
1da177e4 | 26 | #include "xfs_trans_priv.h" |
9e4c109a | 27 | #include "xfs_trace.h" |
1da177e4 | 28 | #include "xfs_error.h" |
239880ef | 29 | #include "xfs_log.h" |
1da177e4 | 30 | |
1da177e4 | 31 | #ifdef DEBUG |
cd4a3c50 DC |
32 | /* |
33 | * Check that the list is sorted as it should be. | |
34 | */ | |
35 | STATIC void | |
36 | xfs_ail_check( | |
37 | struct xfs_ail *ailp, | |
38 | xfs_log_item_t *lip) | |
39 | { | |
40 | xfs_log_item_t *prev_lip; | |
41 | ||
42 | if (list_empty(&ailp->xa_ail)) | |
43 | return; | |
44 | ||
45 | /* | |
46 | * Check the next and previous entries are valid. | |
47 | */ | |
48 | ASSERT((lip->li_flags & XFS_LI_IN_AIL) != 0); | |
49 | prev_lip = list_entry(lip->li_ail.prev, xfs_log_item_t, li_ail); | |
50 | if (&prev_lip->li_ail != &ailp->xa_ail) | |
51 | ASSERT(XFS_LSN_CMP(prev_lip->li_lsn, lip->li_lsn) <= 0); | |
52 | ||
53 | prev_lip = list_entry(lip->li_ail.next, xfs_log_item_t, li_ail); | |
54 | if (&prev_lip->li_ail != &ailp->xa_ail) | |
55 | ASSERT(XFS_LSN_CMP(prev_lip->li_lsn, lip->li_lsn) >= 0); | |
56 | ||
57 | ||
cd4a3c50 DC |
58 | } |
59 | #else /* !DEBUG */ | |
de08dbc1 | 60 | #define xfs_ail_check(a,l) |
1da177e4 LT |
61 | #endif /* DEBUG */ |
62 | ||
cd4a3c50 | 63 | /* |
fd074841 DC |
64 | * Return a pointer to the last item in the AIL. If the AIL is empty, then |
65 | * return NULL. | |
66 | */ | |
67 | static xfs_log_item_t * | |
68 | xfs_ail_max( | |
69 | struct xfs_ail *ailp) | |
70 | { | |
71 | if (list_empty(&ailp->xa_ail)) | |
72 | return NULL; | |
73 | ||
74 | return list_entry(ailp->xa_ail.prev, xfs_log_item_t, li_ail); | |
75 | } | |
76 | ||
cd4a3c50 DC |
77 | /* |
78 | * Return a pointer to the item which follows the given item in the AIL. If | |
79 | * the given item is the last item in the list, then return NULL. | |
80 | */ | |
81 | static xfs_log_item_t * | |
82 | xfs_ail_next( | |
83 | struct xfs_ail *ailp, | |
84 | xfs_log_item_t *lip) | |
85 | { | |
86 | if (lip->li_ail.next == &ailp->xa_ail) | |
87 | return NULL; | |
88 | ||
89 | return list_first_entry(&lip->li_ail, xfs_log_item_t, li_ail); | |
90 | } | |
1da177e4 LT |
91 | |
92 | /* | |
cd4a3c50 DC |
93 | * This is called by the log manager code to determine the LSN of the tail of |
94 | * the log. This is exactly the LSN of the first item in the AIL. If the AIL | |
95 | * is empty, then this function returns 0. | |
1da177e4 | 96 | * |
cd4a3c50 DC |
97 | * We need the AIL lock in order to get a coherent read of the lsn of the last |
98 | * item in the AIL. | |
1da177e4 LT |
99 | */ |
100 | xfs_lsn_t | |
fd074841 | 101 | xfs_ail_min_lsn( |
5b00f14f | 102 | struct xfs_ail *ailp) |
1da177e4 | 103 | { |
cd4a3c50 | 104 | xfs_lsn_t lsn = 0; |
1da177e4 | 105 | xfs_log_item_t *lip; |
1da177e4 | 106 | |
c7e8f268 | 107 | spin_lock(&ailp->xa_lock); |
5b00f14f | 108 | lip = xfs_ail_min(ailp); |
cd4a3c50 | 109 | if (lip) |
1da177e4 | 110 | lsn = lip->li_lsn; |
c7e8f268 | 111 | spin_unlock(&ailp->xa_lock); |
1da177e4 LT |
112 | |
113 | return lsn; | |
114 | } | |
115 | ||
fd074841 DC |
116 | /* |
117 | * Return the maximum lsn held in the AIL, or zero if the AIL is empty. | |
118 | */ | |
119 | static xfs_lsn_t | |
120 | xfs_ail_max_lsn( | |
121 | struct xfs_ail *ailp) | |
122 | { | |
123 | xfs_lsn_t lsn = 0; | |
124 | xfs_log_item_t *lip; | |
125 | ||
126 | spin_lock(&ailp->xa_lock); | |
127 | lip = xfs_ail_max(ailp); | |
128 | if (lip) | |
129 | lsn = lip->li_lsn; | |
130 | spin_unlock(&ailp->xa_lock); | |
131 | ||
132 | return lsn; | |
133 | } | |
134 | ||
27d8d5fe | 135 | /* |
af3e4022 DC |
136 | * The cursor keeps track of where our current traversal is up to by tracking |
137 | * the next item in the list for us. However, for this to be safe, removing an | |
138 | * object from the AIL needs to invalidate any cursor that points to it. hence | |
139 | * the traversal cursor needs to be linked to the struct xfs_ail so that | |
140 | * deletion can search all the active cursors for invalidation. | |
27d8d5fe | 141 | */ |
5b00f14f | 142 | STATIC void |
27d8d5fe DC |
143 | xfs_trans_ail_cursor_init( |
144 | struct xfs_ail *ailp, | |
145 | struct xfs_ail_cursor *cur) | |
146 | { | |
147 | cur->item = NULL; | |
af3e4022 | 148 | list_add_tail(&cur->list, &ailp->xa_cursors); |
27d8d5fe DC |
149 | } |
150 | ||
27d8d5fe | 151 | /* |
af3e4022 DC |
152 | * Get the next item in the traversal and advance the cursor. If the cursor |
153 | * was invalidated (indicated by a lip of 1), restart the traversal. | |
27d8d5fe | 154 | */ |
5b00f14f | 155 | struct xfs_log_item * |
27d8d5fe DC |
156 | xfs_trans_ail_cursor_next( |
157 | struct xfs_ail *ailp, | |
158 | struct xfs_ail_cursor *cur) | |
159 | { | |
160 | struct xfs_log_item *lip = cur->item; | |
161 | ||
db9d67d6 | 162 | if ((uintptr_t)lip & 1) |
27d8d5fe | 163 | lip = xfs_ail_min(ailp); |
16b59029 DC |
164 | if (lip) |
165 | cur->item = xfs_ail_next(ailp, lip); | |
27d8d5fe DC |
166 | return lip; |
167 | } | |
168 | ||
27d8d5fe | 169 | /* |
af3e4022 DC |
170 | * When the traversal is complete, we need to remove the cursor from the list |
171 | * of traversing cursors. | |
27d8d5fe DC |
172 | */ |
173 | void | |
174 | xfs_trans_ail_cursor_done( | |
af3e4022 | 175 | struct xfs_ail_cursor *cur) |
27d8d5fe | 176 | { |
af3e4022 DC |
177 | cur->item = NULL; |
178 | list_del_init(&cur->list); | |
27d8d5fe DC |
179 | } |
180 | ||
5b00f14f | 181 | /* |
af3e4022 DC |
182 | * Invalidate any cursor that is pointing to this item. This is called when an |
183 | * item is removed from the AIL. Any cursor pointing to this object is now | |
184 | * invalid and the traversal needs to be terminated so it doesn't reference a | |
185 | * freed object. We set the low bit of the cursor item pointer so we can | |
186 | * distinguish between an invalidation and the end of the list when getting the | |
187 | * next item from the cursor. | |
5b00f14f DC |
188 | */ |
189 | STATIC void | |
190 | xfs_trans_ail_cursor_clear( | |
191 | struct xfs_ail *ailp, | |
192 | struct xfs_log_item *lip) | |
193 | { | |
194 | struct xfs_ail_cursor *cur; | |
195 | ||
af3e4022 | 196 | list_for_each_entry(cur, &ailp->xa_cursors, list) { |
5b00f14f DC |
197 | if (cur->item == lip) |
198 | cur->item = (struct xfs_log_item *) | |
db9d67d6 | 199 | ((uintptr_t)cur->item | 1); |
5b00f14f DC |
200 | } |
201 | } | |
202 | ||
249a8c11 | 203 | /* |
16b59029 DC |
204 | * Find the first item in the AIL with the given @lsn by searching in ascending |
205 | * LSN order and initialise the cursor to point to the next item for a | |
206 | * ascending traversal. Pass a @lsn of zero to initialise the cursor to the | |
207 | * first item in the AIL. Returns NULL if the list is empty. | |
249a8c11 | 208 | */ |
5b00f14f DC |
209 | xfs_log_item_t * |
210 | xfs_trans_ail_cursor_first( | |
27d8d5fe DC |
211 | struct xfs_ail *ailp, |
212 | struct xfs_ail_cursor *cur, | |
213 | xfs_lsn_t lsn) | |
249a8c11 | 214 | { |
27d8d5fe | 215 | xfs_log_item_t *lip; |
249a8c11 | 216 | |
5b00f14f | 217 | xfs_trans_ail_cursor_init(ailp, cur); |
16b59029 DC |
218 | |
219 | if (lsn == 0) { | |
220 | lip = xfs_ail_min(ailp); | |
5b00f14f | 221 | goto out; |
16b59029 | 222 | } |
249a8c11 | 223 | |
27d8d5fe | 224 | list_for_each_entry(lip, &ailp->xa_ail, li_ail) { |
5b00f14f | 225 | if (XFS_LSN_CMP(lip->li_lsn, lsn) >= 0) |
7ee49acf | 226 | goto out; |
535f6b37 | 227 | } |
16b59029 DC |
228 | return NULL; |
229 | ||
5b00f14f | 230 | out: |
16b59029 DC |
231 | if (lip) |
232 | cur->item = xfs_ail_next(ailp, lip); | |
5b00f14f | 233 | return lip; |
249a8c11 DC |
234 | } |
235 | ||
1d8c95a3 DC |
236 | static struct xfs_log_item * |
237 | __xfs_trans_ail_cursor_last( | |
238 | struct xfs_ail *ailp, | |
239 | xfs_lsn_t lsn) | |
240 | { | |
241 | xfs_log_item_t *lip; | |
242 | ||
243 | list_for_each_entry_reverse(lip, &ailp->xa_ail, li_ail) { | |
244 | if (XFS_LSN_CMP(lip->li_lsn, lsn) <= 0) | |
245 | return lip; | |
246 | } | |
247 | return NULL; | |
248 | } | |
249 | ||
250 | /* | |
16b59029 DC |
251 | * Find the last item in the AIL with the given @lsn by searching in descending |
252 | * LSN order and initialise the cursor to point to that item. If there is no | |
253 | * item with the value of @lsn, then it sets the cursor to the last item with an | |
254 | * LSN lower than @lsn. Returns NULL if the list is empty. | |
1d8c95a3 DC |
255 | */ |
256 | struct xfs_log_item * | |
257 | xfs_trans_ail_cursor_last( | |
258 | struct xfs_ail *ailp, | |
259 | struct xfs_ail_cursor *cur, | |
260 | xfs_lsn_t lsn) | |
261 | { | |
262 | xfs_trans_ail_cursor_init(ailp, cur); | |
263 | cur->item = __xfs_trans_ail_cursor_last(ailp, lsn); | |
264 | return cur->item; | |
265 | } | |
266 | ||
267 | /* | |
16b59029 | 268 | * Splice the log item list into the AIL at the given LSN. We splice to the |
1d8c95a3 DC |
269 | * tail of the given LSN to maintain insert order for push traversals. The |
270 | * cursor is optional, allowing repeated updates to the same LSN to avoid | |
e44f4112 | 271 | * repeated traversals. This should not be called with an empty list. |
cd4a3c50 DC |
272 | */ |
273 | static void | |
274 | xfs_ail_splice( | |
1d8c95a3 DC |
275 | struct xfs_ail *ailp, |
276 | struct xfs_ail_cursor *cur, | |
277 | struct list_head *list, | |
278 | xfs_lsn_t lsn) | |
cd4a3c50 | 279 | { |
e44f4112 AE |
280 | struct xfs_log_item *lip; |
281 | ||
282 | ASSERT(!list_empty(list)); | |
cd4a3c50 | 283 | |
1d8c95a3 | 284 | /* |
e44f4112 AE |
285 | * Use the cursor to determine the insertion point if one is |
286 | * provided. If not, or if the one we got is not valid, | |
287 | * find the place in the AIL where the items belong. | |
1d8c95a3 | 288 | */ |
e44f4112 | 289 | lip = cur ? cur->item : NULL; |
db9d67d6 | 290 | if (!lip || (uintptr_t)lip & 1) |
1d8c95a3 DC |
291 | lip = __xfs_trans_ail_cursor_last(ailp, lsn); |
292 | ||
e44f4112 AE |
293 | /* |
294 | * If a cursor is provided, we know we're processing the AIL | |
295 | * in lsn order, and future items to be spliced in will | |
296 | * follow the last one being inserted now. Update the | |
297 | * cursor to point to that last item, now while we have a | |
298 | * reliable pointer to it. | |
299 | */ | |
300 | if (cur) | |
301 | cur->item = list_entry(list->prev, struct xfs_log_item, li_ail); | |
cd4a3c50 | 302 | |
1d8c95a3 | 303 | /* |
e44f4112 AE |
304 | * Finally perform the splice. Unless the AIL was empty, |
305 | * lip points to the item in the AIL _after_ which the new | |
306 | * items should go. If lip is null the AIL was empty, so | |
307 | * the new items go at the head of the AIL. | |
1d8c95a3 | 308 | */ |
e44f4112 AE |
309 | if (lip) |
310 | list_splice(list, &lip->li_ail); | |
311 | else | |
312 | list_splice(list, &ailp->xa_ail); | |
cd4a3c50 DC |
313 | } |
314 | ||
315 | /* | |
316 | * Delete the given item from the AIL. Return a pointer to the item. | |
317 | */ | |
318 | static void | |
319 | xfs_ail_delete( | |
320 | struct xfs_ail *ailp, | |
321 | xfs_log_item_t *lip) | |
322 | { | |
323 | xfs_ail_check(ailp, lip); | |
324 | list_del(&lip->li_ail); | |
325 | xfs_trans_ail_cursor_clear(ailp, lip); | |
326 | } | |
327 | ||
0030807c CH |
328 | static long |
329 | xfsaild_push( | |
330 | struct xfs_ail *ailp) | |
249a8c11 | 331 | { |
9e7004e7 | 332 | xfs_mount_t *mp = ailp->xa_mount; |
af3e4022 | 333 | struct xfs_ail_cursor cur; |
9e7004e7 DC |
334 | xfs_log_item_t *lip; |
335 | xfs_lsn_t lsn; | |
fe0da767 | 336 | xfs_lsn_t target; |
43ff2122 | 337 | long tout; |
9e7004e7 | 338 | int stuck = 0; |
43ff2122 | 339 | int flushing = 0; |
9e7004e7 | 340 | int count = 0; |
1da177e4 | 341 | |
670ce93f | 342 | /* |
43ff2122 CH |
343 | * If we encountered pinned items or did not finish writing out all |
344 | * buffers the last time we ran, force the log first and wait for it | |
345 | * before pushing again. | |
670ce93f | 346 | */ |
43ff2122 CH |
347 | if (ailp->xa_log_flush && ailp->xa_last_pushed_lsn == 0 && |
348 | (!list_empty_careful(&ailp->xa_buf_list) || | |
349 | xfs_ail_min_lsn(ailp))) { | |
670ce93f | 350 | ailp->xa_log_flush = 0; |
43ff2122 | 351 | |
ff6d6af2 | 352 | XFS_STATS_INC(mp, xs_push_ail_flush); |
670ce93f | 353 | xfs_log_force(mp, XFS_LOG_SYNC); |
670ce93f DC |
354 | } |
355 | ||
43ff2122 | 356 | spin_lock(&ailp->xa_lock); |
8375f922 BF |
357 | |
358 | /* barrier matches the xa_target update in xfs_ail_push() */ | |
359 | smp_rmb(); | |
360 | target = ailp->xa_target; | |
361 | ailp->xa_target_prev = target; | |
362 | ||
af3e4022 | 363 | lip = xfs_trans_ail_cursor_first(ailp, &cur, ailp->xa_last_pushed_lsn); |
211e4d43 | 364 | if (!lip) { |
1da177e4 | 365 | /* |
43ff2122 CH |
366 | * If the AIL is empty or our push has reached the end we are |
367 | * done now. | |
1da177e4 | 368 | */ |
e4a1e29c | 369 | xfs_trans_ail_cursor_done(&cur); |
c7e8f268 | 370 | spin_unlock(&ailp->xa_lock); |
9e7004e7 | 371 | goto out_done; |
1da177e4 LT |
372 | } |
373 | ||
ff6d6af2 | 374 | XFS_STATS_INC(mp, xs_push_ail); |
1da177e4 | 375 | |
249a8c11 | 376 | lsn = lip->li_lsn; |
50e86686 | 377 | while ((XFS_LSN_CMP(lip->li_lsn, target) <= 0)) { |
249a8c11 | 378 | int lock_result; |
43ff2122 | 379 | |
1da177e4 | 380 | /* |
904c17e6 | 381 | * Note that iop_push may unlock and reacquire the AIL lock. We |
43ff2122 CH |
382 | * rely on the AIL cursor implementation to be able to deal with |
383 | * the dropped lock. | |
1da177e4 | 384 | */ |
904c17e6 | 385 | lock_result = lip->li_ops->iop_push(lip, &ailp->xa_buf_list); |
1da177e4 | 386 | switch (lock_result) { |
249a8c11 | 387 | case XFS_ITEM_SUCCESS: |
ff6d6af2 | 388 | XFS_STATS_INC(mp, xs_push_ail_success); |
9e4c109a CH |
389 | trace_xfs_ail_push(lip); |
390 | ||
0bf6a5bd | 391 | ailp->xa_last_pushed_lsn = lsn; |
1da177e4 LT |
392 | break; |
393 | ||
43ff2122 CH |
394 | case XFS_ITEM_FLUSHING: |
395 | /* | |
396 | * The item or its backing buffer is already beeing | |
397 | * flushed. The typical reason for that is that an | |
398 | * inode buffer is locked because we already pushed the | |
399 | * updates to it as part of inode clustering. | |
400 | * | |
401 | * We do not want to to stop flushing just because lots | |
402 | * of items are already beeing flushed, but we need to | |
403 | * re-try the flushing relatively soon if most of the | |
404 | * AIL is beeing flushed. | |
405 | */ | |
ff6d6af2 | 406 | XFS_STATS_INC(mp, xs_push_ail_flushing); |
43ff2122 CH |
407 | trace_xfs_ail_flushing(lip); |
408 | ||
409 | flushing++; | |
410 | ailp->xa_last_pushed_lsn = lsn; | |
1da177e4 LT |
411 | break; |
412 | ||
249a8c11 | 413 | case XFS_ITEM_PINNED: |
ff6d6af2 | 414 | XFS_STATS_INC(mp, xs_push_ail_pinned); |
9e4c109a CH |
415 | trace_xfs_ail_pinned(lip); |
416 | ||
249a8c11 | 417 | stuck++; |
670ce93f | 418 | ailp->xa_log_flush++; |
1da177e4 | 419 | break; |
249a8c11 | 420 | case XFS_ITEM_LOCKED: |
ff6d6af2 | 421 | XFS_STATS_INC(mp, xs_push_ail_locked); |
9e4c109a | 422 | trace_xfs_ail_locked(lip); |
43ff2122 | 423 | |
249a8c11 | 424 | stuck++; |
1da177e4 | 425 | break; |
249a8c11 | 426 | default: |
1da177e4 LT |
427 | ASSERT(0); |
428 | break; | |
429 | } | |
430 | ||
249a8c11 | 431 | count++; |
1da177e4 | 432 | |
249a8c11 DC |
433 | /* |
434 | * Are there too many items we can't do anything with? | |
43ff2122 | 435 | * |
249a8c11 DC |
436 | * If we we are skipping too many items because we can't flush |
437 | * them or they are already being flushed, we back off and | |
438 | * given them time to complete whatever operation is being | |
439 | * done. i.e. remove pressure from the AIL while we can't make | |
440 | * progress so traversals don't slow down further inserts and | |
441 | * removals to/from the AIL. | |
442 | * | |
443 | * The value of 100 is an arbitrary magic number based on | |
444 | * observation. | |
445 | */ | |
446 | if (stuck > 100) | |
447 | break; | |
448 | ||
af3e4022 | 449 | lip = xfs_trans_ail_cursor_next(ailp, &cur); |
249a8c11 DC |
450 | if (lip == NULL) |
451 | break; | |
249a8c11 | 452 | lsn = lip->li_lsn; |
1da177e4 | 453 | } |
e4a1e29c | 454 | xfs_trans_ail_cursor_done(&cur); |
c7e8f268 | 455 | spin_unlock(&ailp->xa_lock); |
1da177e4 | 456 | |
43ff2122 CH |
457 | if (xfs_buf_delwri_submit_nowait(&ailp->xa_buf_list)) |
458 | ailp->xa_log_flush++; | |
d808f617 | 459 | |
43ff2122 | 460 | if (!count || XFS_LSN_CMP(lsn, target) >= 0) { |
9e7004e7 | 461 | out_done: |
92d9cd10 | 462 | /* |
43ff2122 CH |
463 | * We reached the target or the AIL is empty, so wait a bit |
464 | * longer for I/O to complete and remove pushed items from the | |
465 | * AIL before we start the next scan from the start of the AIL. | |
92d9cd10 | 466 | */ |
453eac8a | 467 | tout = 50; |
0bf6a5bd | 468 | ailp->xa_last_pushed_lsn = 0; |
43ff2122 | 469 | } else if (((stuck + flushing) * 100) / count > 90) { |
249a8c11 | 470 | /* |
43ff2122 CH |
471 | * Either there is a lot of contention on the AIL or we are |
472 | * stuck due to operations in progress. "Stuck" in this case | |
473 | * is defined as >90% of the items we tried to push were stuck. | |
249a8c11 DC |
474 | * |
475 | * Backoff a bit more to allow some I/O to complete before | |
43ff2122 CH |
476 | * restarting from the start of the AIL. This prevents us from |
477 | * spinning on the same items, and if they are pinned will all | |
478 | * the restart to issue a log force to unpin the stuck items. | |
249a8c11 | 479 | */ |
453eac8a | 480 | tout = 20; |
670ce93f | 481 | ailp->xa_last_pushed_lsn = 0; |
43ff2122 CH |
482 | } else { |
483 | /* | |
484 | * Assume we have more work to do in a short while. | |
485 | */ | |
486 | tout = 10; | |
1da177e4 | 487 | } |
0bf6a5bd | 488 | |
0030807c CH |
489 | return tout; |
490 | } | |
491 | ||
492 | static int | |
493 | xfsaild( | |
494 | void *data) | |
495 | { | |
496 | struct xfs_ail *ailp = data; | |
497 | long tout = 0; /* milliseconds */ | |
498 | ||
43ff2122 | 499 | current->flags |= PF_MEMALLOC; |
18f1df4e | 500 | set_freezable(); |
43ff2122 | 501 | |
0030807c CH |
502 | while (!kthread_should_stop()) { |
503 | if (tout && tout <= 20) | |
504 | __set_current_state(TASK_KILLABLE); | |
505 | else | |
506 | __set_current_state(TASK_INTERRUPTIBLE); | |
8375f922 BF |
507 | |
508 | spin_lock(&ailp->xa_lock); | |
509 | ||
510 | /* | |
511 | * Idle if the AIL is empty and we are not racing with a target | |
512 | * update. We check the AIL after we set the task to a sleep | |
513 | * state to guarantee that we either catch an xa_target update | |
514 | * or that a wake_up resets the state to TASK_RUNNING. | |
515 | * Otherwise, we run the risk of sleeping indefinitely. | |
516 | * | |
517 | * The barrier matches the xa_target update in xfs_ail_push(). | |
518 | */ | |
519 | smp_rmb(); | |
520 | if (!xfs_ail_min(ailp) && | |
521 | ailp->xa_target == ailp->xa_target_prev) { | |
522 | spin_unlock(&ailp->xa_lock); | |
18f1df4e | 523 | freezable_schedule(); |
8375f922 BF |
524 | tout = 0; |
525 | continue; | |
526 | } | |
527 | spin_unlock(&ailp->xa_lock); | |
528 | ||
529 | if (tout) | |
18f1df4e | 530 | freezable_schedule_timeout(msecs_to_jiffies(tout)); |
8375f922 BF |
531 | |
532 | __set_current_state(TASK_RUNNING); | |
0030807c CH |
533 | |
534 | try_to_freeze(); | |
535 | ||
536 | tout = xfsaild_push(ailp); | |
537 | } | |
538 | ||
539 | return 0; | |
453eac8a | 540 | } |
1da177e4 | 541 | |
0bf6a5bd DC |
542 | /* |
543 | * This routine is called to move the tail of the AIL forward. It does this by | |
544 | * trying to flush items in the AIL whose lsns are below the given | |
545 | * threshold_lsn. | |
546 | * | |
547 | * The push is run asynchronously in a workqueue, which means the caller needs | |
548 | * to handle waiting on the async flush for space to become available. | |
549 | * We don't want to interrupt any push that is in progress, hence we only queue | |
550 | * work if we set the pushing bit approriately. | |
551 | * | |
552 | * We do this unlocked - we only need to know whether there is anything in the | |
553 | * AIL at the time we are called. We don't need to access the contents of | |
554 | * any of the objects, so the lock is not needed. | |
555 | */ | |
556 | void | |
fd074841 | 557 | xfs_ail_push( |
0bf6a5bd DC |
558 | struct xfs_ail *ailp, |
559 | xfs_lsn_t threshold_lsn) | |
560 | { | |
561 | xfs_log_item_t *lip; | |
562 | ||
563 | lip = xfs_ail_min(ailp); | |
564 | if (!lip || XFS_FORCED_SHUTDOWN(ailp->xa_mount) || | |
565 | XFS_LSN_CMP(threshold_lsn, ailp->xa_target) <= 0) | |
566 | return; | |
567 | ||
568 | /* | |
569 | * Ensure that the new target is noticed in push code before it clears | |
570 | * the XFS_AIL_PUSHING_BIT. | |
571 | */ | |
572 | smp_wmb(); | |
fe0da767 | 573 | xfs_trans_ail_copy_lsn(ailp, &ailp->xa_target, &threshold_lsn); |
0030807c CH |
574 | smp_wmb(); |
575 | ||
576 | wake_up_process(ailp->xa_task); | |
0bf6a5bd | 577 | } |
1da177e4 | 578 | |
fd074841 DC |
579 | /* |
580 | * Push out all items in the AIL immediately | |
581 | */ | |
582 | void | |
583 | xfs_ail_push_all( | |
584 | struct xfs_ail *ailp) | |
585 | { | |
586 | xfs_lsn_t threshold_lsn = xfs_ail_max_lsn(ailp); | |
587 | ||
588 | if (threshold_lsn) | |
589 | xfs_ail_push(ailp, threshold_lsn); | |
590 | } | |
591 | ||
211e4d43 CH |
592 | /* |
593 | * Push out all items in the AIL immediately and wait until the AIL is empty. | |
594 | */ | |
595 | void | |
596 | xfs_ail_push_all_sync( | |
597 | struct xfs_ail *ailp) | |
598 | { | |
599 | struct xfs_log_item *lip; | |
600 | DEFINE_WAIT(wait); | |
601 | ||
602 | spin_lock(&ailp->xa_lock); | |
603 | while ((lip = xfs_ail_max(ailp)) != NULL) { | |
604 | prepare_to_wait(&ailp->xa_empty, &wait, TASK_UNINTERRUPTIBLE); | |
605 | ailp->xa_target = lip->li_lsn; | |
606 | wake_up_process(ailp->xa_task); | |
607 | spin_unlock(&ailp->xa_lock); | |
608 | schedule(); | |
609 | spin_lock(&ailp->xa_lock); | |
610 | } | |
611 | spin_unlock(&ailp->xa_lock); | |
612 | ||
613 | finish_wait(&ailp->xa_empty, &wait); | |
614 | } | |
615 | ||
0e57f6a3 DC |
616 | /* |
617 | * xfs_trans_ail_update - bulk AIL insertion operation. | |
618 | * | |
619 | * @xfs_trans_ail_update takes an array of log items that all need to be | |
620 | * positioned at the same LSN in the AIL. If an item is not in the AIL, it will | |
621 | * be added. Otherwise, it will be repositioned by removing it and re-adding | |
622 | * it to the AIL. If we move the first item in the AIL, update the log tail to | |
623 | * match the new minimum LSN in the AIL. | |
624 | * | |
625 | * This function takes the AIL lock once to execute the update operations on | |
626 | * all the items in the array, and as such should not be called with the AIL | |
627 | * lock held. As a result, once we have the AIL lock, we need to check each log | |
628 | * item LSN to confirm it needs to be moved forward in the AIL. | |
629 | * | |
630 | * To optimise the insert operation, we delete all the items from the AIL in | |
631 | * the first pass, moving them into a temporary list, then splice the temporary | |
632 | * list into the correct position in the AIL. This avoids needing to do an | |
633 | * insert operation on every item. | |
634 | * | |
635 | * This function must be called with the AIL lock held. The lock is dropped | |
636 | * before returning. | |
637 | */ | |
638 | void | |
639 | xfs_trans_ail_update_bulk( | |
640 | struct xfs_ail *ailp, | |
1d8c95a3 | 641 | struct xfs_ail_cursor *cur, |
0e57f6a3 DC |
642 | struct xfs_log_item **log_items, |
643 | int nr_items, | |
644 | xfs_lsn_t lsn) __releases(ailp->xa_lock) | |
645 | { | |
646 | xfs_log_item_t *mlip; | |
0e57f6a3 DC |
647 | int mlip_changed = 0; |
648 | int i; | |
649 | LIST_HEAD(tmp); | |
650 | ||
e44f4112 | 651 | ASSERT(nr_items > 0); /* Not required, but true. */ |
0e57f6a3 DC |
652 | mlip = xfs_ail_min(ailp); |
653 | ||
654 | for (i = 0; i < nr_items; i++) { | |
655 | struct xfs_log_item *lip = log_items[i]; | |
656 | if (lip->li_flags & XFS_LI_IN_AIL) { | |
657 | /* check if we really need to move the item */ | |
658 | if (XFS_LSN_CMP(lsn, lip->li_lsn) <= 0) | |
659 | continue; | |
660 | ||
750b9c90 | 661 | trace_xfs_ail_move(lip, lip->li_lsn, lsn); |
0e57f6a3 DC |
662 | xfs_ail_delete(ailp, lip); |
663 | if (mlip == lip) | |
664 | mlip_changed = 1; | |
665 | } else { | |
666 | lip->li_flags |= XFS_LI_IN_AIL; | |
750b9c90 | 667 | trace_xfs_ail_insert(lip, 0, lsn); |
0e57f6a3 DC |
668 | } |
669 | lip->li_lsn = lsn; | |
670 | list_add(&lip->li_ail, &tmp); | |
671 | } | |
672 | ||
e44f4112 AE |
673 | if (!list_empty(&tmp)) |
674 | xfs_ail_splice(ailp, cur, &tmp, lsn); | |
0e57f6a3 | 675 | |
1c304625 CH |
676 | if (mlip_changed) { |
677 | if (!XFS_FORCED_SHUTDOWN(ailp->xa_mount)) | |
678 | xlog_assign_tail_lsn_locked(ailp->xa_mount); | |
679 | spin_unlock(&ailp->xa_lock); | |
680 | ||
cfb7cdca | 681 | xfs_log_space_wake(ailp->xa_mount); |
1c304625 CH |
682 | } else { |
683 | spin_unlock(&ailp->xa_lock); | |
0e57f6a3 | 684 | } |
0e57f6a3 DC |
685 | } |
686 | ||
30136832 DC |
687 | /* |
688 | * xfs_trans_ail_delete_bulk - remove multiple log items from the AIL | |
689 | * | |
690 | * @xfs_trans_ail_delete_bulk takes an array of log items that all need to | |
691 | * removed from the AIL. The caller is already holding the AIL lock, and done | |
692 | * all the checks necessary to ensure the items passed in via @log_items are | |
693 | * ready for deletion. This includes checking that the items are in the AIL. | |
694 | * | |
695 | * For each log item to be removed, unlink it from the AIL, clear the IN_AIL | |
696 | * flag from the item and reset the item's lsn to 0. If we remove the first | |
697 | * item in the AIL, update the log tail to match the new minimum LSN in the | |
698 | * AIL. | |
699 | * | |
700 | * This function will not drop the AIL lock until all items are removed from | |
701 | * the AIL to minimise the amount of lock traffic on the AIL. This does not | |
702 | * greatly increase the AIL hold time, but does significantly reduce the amount | |
703 | * of traffic on the lock, especially during IO completion. | |
704 | * | |
705 | * This function must be called with the AIL lock held. The lock is dropped | |
706 | * before returning. | |
707 | */ | |
708 | void | |
709 | xfs_trans_ail_delete_bulk( | |
710 | struct xfs_ail *ailp, | |
711 | struct xfs_log_item **log_items, | |
04913fdd DC |
712 | int nr_items, |
713 | int shutdown_type) __releases(ailp->xa_lock) | |
30136832 DC |
714 | { |
715 | xfs_log_item_t *mlip; | |
30136832 DC |
716 | int mlip_changed = 0; |
717 | int i; | |
718 | ||
719 | mlip = xfs_ail_min(ailp); | |
720 | ||
721 | for (i = 0; i < nr_items; i++) { | |
722 | struct xfs_log_item *lip = log_items[i]; | |
723 | if (!(lip->li_flags & XFS_LI_IN_AIL)) { | |
724 | struct xfs_mount *mp = ailp->xa_mount; | |
725 | ||
726 | spin_unlock(&ailp->xa_lock); | |
727 | if (!XFS_FORCED_SHUTDOWN(mp)) { | |
6a19d939 | 728 | xfs_alert_tag(mp, XFS_PTAG_AILDELETE, |
30136832 DC |
729 | "%s: attempting to delete a log item that is not in the AIL", |
730 | __func__); | |
04913fdd | 731 | xfs_force_shutdown(mp, shutdown_type); |
30136832 DC |
732 | } |
733 | return; | |
734 | } | |
735 | ||
750b9c90 | 736 | trace_xfs_ail_delete(lip, mlip->li_lsn, lip->li_lsn); |
30136832 DC |
737 | xfs_ail_delete(ailp, lip); |
738 | lip->li_flags &= ~XFS_LI_IN_AIL; | |
739 | lip->li_lsn = 0; | |
740 | if (mlip == lip) | |
741 | mlip_changed = 1; | |
742 | } | |
743 | ||
1c304625 CH |
744 | if (mlip_changed) { |
745 | if (!XFS_FORCED_SHUTDOWN(ailp->xa_mount)) | |
746 | xlog_assign_tail_lsn_locked(ailp->xa_mount); | |
211e4d43 CH |
747 | if (list_empty(&ailp->xa_ail)) |
748 | wake_up_all(&ailp->xa_empty); | |
1c304625 CH |
749 | spin_unlock(&ailp->xa_lock); |
750 | ||
cfb7cdca | 751 | xfs_log_space_wake(ailp->xa_mount); |
1c304625 CH |
752 | } else { |
753 | spin_unlock(&ailp->xa_lock); | |
30136832 | 754 | } |
30136832 | 755 | } |
1da177e4 | 756 | |
249a8c11 | 757 | int |
1da177e4 LT |
758 | xfs_trans_ail_init( |
759 | xfs_mount_t *mp) | |
760 | { | |
82fa9012 DC |
761 | struct xfs_ail *ailp; |
762 | ||
763 | ailp = kmem_zalloc(sizeof(struct xfs_ail), KM_MAYFAIL); | |
764 | if (!ailp) | |
2451337d | 765 | return -ENOMEM; |
82fa9012 DC |
766 | |
767 | ailp->xa_mount = mp; | |
768 | INIT_LIST_HEAD(&ailp->xa_ail); | |
af3e4022 | 769 | INIT_LIST_HEAD(&ailp->xa_cursors); |
c7e8f268 | 770 | spin_lock_init(&ailp->xa_lock); |
43ff2122 | 771 | INIT_LIST_HEAD(&ailp->xa_buf_list); |
211e4d43 | 772 | init_waitqueue_head(&ailp->xa_empty); |
0030807c CH |
773 | |
774 | ailp->xa_task = kthread_run(xfsaild, ailp, "xfsaild/%s", | |
775 | ailp->xa_mount->m_fsname); | |
776 | if (IS_ERR(ailp->xa_task)) | |
777 | goto out_free_ailp; | |
778 | ||
27d8d5fe DC |
779 | mp->m_ail = ailp; |
780 | return 0; | |
0030807c CH |
781 | |
782 | out_free_ailp: | |
783 | kmem_free(ailp); | |
2451337d | 784 | return -ENOMEM; |
249a8c11 DC |
785 | } |
786 | ||
787 | void | |
788 | xfs_trans_ail_destroy( | |
789 | xfs_mount_t *mp) | |
790 | { | |
82fa9012 DC |
791 | struct xfs_ail *ailp = mp->m_ail; |
792 | ||
0030807c | 793 | kthread_stop(ailp->xa_task); |
82fa9012 | 794 | kmem_free(ailp); |
1da177e4 | 795 | } |