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" |
1da177e4 | 21 | #include "xfs_types.h" |
1da177e4 | 22 | #include "xfs_log.h" |
a844f451 | 23 | #include "xfs_inum.h" |
1da177e4 LT |
24 | #include "xfs_trans.h" |
25 | #include "xfs_sb.h" | |
da353b0d | 26 | #include "xfs_ag.h" |
1da177e4 LT |
27 | #include "xfs_mount.h" |
28 | #include "xfs_trans_priv.h" | |
9e4c109a | 29 | #include "xfs_trace.h" |
1da177e4 LT |
30 | #include "xfs_error.h" |
31 | ||
1da177e4 | 32 | #ifdef DEBUG |
cd4a3c50 DC |
33 | /* |
34 | * Check that the list is sorted as it should be. | |
35 | */ | |
36 | STATIC void | |
37 | xfs_ail_check( | |
38 | struct xfs_ail *ailp, | |
39 | xfs_log_item_t *lip) | |
40 | { | |
41 | xfs_log_item_t *prev_lip; | |
42 | ||
43 | if (list_empty(&ailp->xa_ail)) | |
44 | return; | |
45 | ||
46 | /* | |
47 | * Check the next and previous entries are valid. | |
48 | */ | |
49 | ASSERT((lip->li_flags & XFS_LI_IN_AIL) != 0); | |
50 | prev_lip = list_entry(lip->li_ail.prev, xfs_log_item_t, li_ail); | |
51 | if (&prev_lip->li_ail != &ailp->xa_ail) | |
52 | ASSERT(XFS_LSN_CMP(prev_lip->li_lsn, lip->li_lsn) <= 0); | |
53 | ||
54 | prev_lip = list_entry(lip->li_ail.next, xfs_log_item_t, li_ail); | |
55 | if (&prev_lip->li_ail != &ailp->xa_ail) | |
56 | ASSERT(XFS_LSN_CMP(prev_lip->li_lsn, lip->li_lsn) >= 0); | |
57 | ||
58 | ||
59 | #ifdef XFS_TRANS_DEBUG | |
60 | /* | |
61 | * Walk the list checking lsn ordering, and that every entry has the | |
62 | * XFS_LI_IN_AIL flag set. This is really expensive, so only do it | |
63 | * when specifically debugging the transaction subsystem. | |
64 | */ | |
65 | prev_lip = list_entry(&ailp->xa_ail, xfs_log_item_t, li_ail); | |
66 | list_for_each_entry(lip, &ailp->xa_ail, li_ail) { | |
67 | if (&prev_lip->li_ail != &ailp->xa_ail) | |
68 | ASSERT(XFS_LSN_CMP(prev_lip->li_lsn, lip->li_lsn) <= 0); | |
69 | ASSERT((lip->li_flags & XFS_LI_IN_AIL) != 0); | |
70 | prev_lip = lip; | |
71 | } | |
72 | #endif /* XFS_TRANS_DEBUG */ | |
73 | } | |
74 | #else /* !DEBUG */ | |
de08dbc1 | 75 | #define xfs_ail_check(a,l) |
1da177e4 LT |
76 | #endif /* DEBUG */ |
77 | ||
cd4a3c50 DC |
78 | /* |
79 | * Return a pointer to the first item in the AIL. If the AIL is empty, then | |
80 | * return NULL. | |
81 | */ | |
1c304625 | 82 | xfs_log_item_t * |
cd4a3c50 DC |
83 | xfs_ail_min( |
84 | struct xfs_ail *ailp) | |
85 | { | |
86 | if (list_empty(&ailp->xa_ail)) | |
87 | return NULL; | |
88 | ||
89 | return list_first_entry(&ailp->xa_ail, xfs_log_item_t, li_ail); | |
90 | } | |
91 | ||
fd074841 DC |
92 | /* |
93 | * Return a pointer to the last item in the AIL. If the AIL is empty, then | |
94 | * return NULL. | |
95 | */ | |
96 | static xfs_log_item_t * | |
97 | xfs_ail_max( | |
98 | struct xfs_ail *ailp) | |
99 | { | |
100 | if (list_empty(&ailp->xa_ail)) | |
101 | return NULL; | |
102 | ||
103 | return list_entry(ailp->xa_ail.prev, xfs_log_item_t, li_ail); | |
104 | } | |
105 | ||
cd4a3c50 DC |
106 | /* |
107 | * Return a pointer to the item which follows the given item in the AIL. If | |
108 | * the given item is the last item in the list, then return NULL. | |
109 | */ | |
110 | static xfs_log_item_t * | |
111 | xfs_ail_next( | |
112 | struct xfs_ail *ailp, | |
113 | xfs_log_item_t *lip) | |
114 | { | |
115 | if (lip->li_ail.next == &ailp->xa_ail) | |
116 | return NULL; | |
117 | ||
118 | return list_first_entry(&lip->li_ail, xfs_log_item_t, li_ail); | |
119 | } | |
1da177e4 LT |
120 | |
121 | /* | |
cd4a3c50 DC |
122 | * This is called by the log manager code to determine the LSN of the tail of |
123 | * the log. This is exactly the LSN of the first item in the AIL. If the AIL | |
124 | * is empty, then this function returns 0. | |
1da177e4 | 125 | * |
cd4a3c50 DC |
126 | * We need the AIL lock in order to get a coherent read of the lsn of the last |
127 | * item in the AIL. | |
1da177e4 LT |
128 | */ |
129 | xfs_lsn_t | |
fd074841 | 130 | xfs_ail_min_lsn( |
5b00f14f | 131 | struct xfs_ail *ailp) |
1da177e4 | 132 | { |
cd4a3c50 | 133 | xfs_lsn_t lsn = 0; |
1da177e4 | 134 | xfs_log_item_t *lip; |
1da177e4 | 135 | |
c7e8f268 | 136 | spin_lock(&ailp->xa_lock); |
5b00f14f | 137 | lip = xfs_ail_min(ailp); |
cd4a3c50 | 138 | if (lip) |
1da177e4 | 139 | lsn = lip->li_lsn; |
c7e8f268 | 140 | spin_unlock(&ailp->xa_lock); |
1da177e4 LT |
141 | |
142 | return lsn; | |
143 | } | |
144 | ||
fd074841 DC |
145 | /* |
146 | * Return the maximum lsn held in the AIL, or zero if the AIL is empty. | |
147 | */ | |
148 | static xfs_lsn_t | |
149 | xfs_ail_max_lsn( | |
150 | struct xfs_ail *ailp) | |
151 | { | |
152 | xfs_lsn_t lsn = 0; | |
153 | xfs_log_item_t *lip; | |
154 | ||
155 | spin_lock(&ailp->xa_lock); | |
156 | lip = xfs_ail_max(ailp); | |
157 | if (lip) | |
158 | lsn = lip->li_lsn; | |
159 | spin_unlock(&ailp->xa_lock); | |
160 | ||
161 | return lsn; | |
162 | } | |
163 | ||
27d8d5fe | 164 | /* |
af3e4022 DC |
165 | * The cursor keeps track of where our current traversal is up to by tracking |
166 | * the next item in the list for us. However, for this to be safe, removing an | |
167 | * object from the AIL needs to invalidate any cursor that points to it. hence | |
168 | * the traversal cursor needs to be linked to the struct xfs_ail so that | |
169 | * deletion can search all the active cursors for invalidation. | |
27d8d5fe | 170 | */ |
5b00f14f | 171 | STATIC void |
27d8d5fe DC |
172 | xfs_trans_ail_cursor_init( |
173 | struct xfs_ail *ailp, | |
174 | struct xfs_ail_cursor *cur) | |
175 | { | |
176 | cur->item = NULL; | |
af3e4022 | 177 | list_add_tail(&cur->list, &ailp->xa_cursors); |
27d8d5fe DC |
178 | } |
179 | ||
27d8d5fe | 180 | /* |
af3e4022 DC |
181 | * Get the next item in the traversal and advance the cursor. If the cursor |
182 | * was invalidated (indicated by a lip of 1), restart the traversal. | |
27d8d5fe | 183 | */ |
5b00f14f | 184 | struct xfs_log_item * |
27d8d5fe DC |
185 | xfs_trans_ail_cursor_next( |
186 | struct xfs_ail *ailp, | |
187 | struct xfs_ail_cursor *cur) | |
188 | { | |
189 | struct xfs_log_item *lip = cur->item; | |
190 | ||
191 | if ((__psint_t)lip & 1) | |
192 | lip = xfs_ail_min(ailp); | |
16b59029 DC |
193 | if (lip) |
194 | cur->item = xfs_ail_next(ailp, lip); | |
27d8d5fe DC |
195 | return lip; |
196 | } | |
197 | ||
27d8d5fe | 198 | /* |
af3e4022 DC |
199 | * When the traversal is complete, we need to remove the cursor from the list |
200 | * of traversing cursors. | |
27d8d5fe DC |
201 | */ |
202 | void | |
203 | xfs_trans_ail_cursor_done( | |
204 | struct xfs_ail *ailp, | |
af3e4022 | 205 | struct xfs_ail_cursor *cur) |
27d8d5fe | 206 | { |
af3e4022 DC |
207 | cur->item = NULL; |
208 | list_del_init(&cur->list); | |
27d8d5fe DC |
209 | } |
210 | ||
5b00f14f | 211 | /* |
af3e4022 DC |
212 | * Invalidate any cursor that is pointing to this item. This is called when an |
213 | * item is removed from the AIL. Any cursor pointing to this object is now | |
214 | * invalid and the traversal needs to be terminated so it doesn't reference a | |
215 | * freed object. We set the low bit of the cursor item pointer so we can | |
216 | * distinguish between an invalidation and the end of the list when getting the | |
217 | * next item from the cursor. | |
5b00f14f DC |
218 | */ |
219 | STATIC void | |
220 | xfs_trans_ail_cursor_clear( | |
221 | struct xfs_ail *ailp, | |
222 | struct xfs_log_item *lip) | |
223 | { | |
224 | struct xfs_ail_cursor *cur; | |
225 | ||
af3e4022 | 226 | list_for_each_entry(cur, &ailp->xa_cursors, list) { |
5b00f14f DC |
227 | if (cur->item == lip) |
228 | cur->item = (struct xfs_log_item *) | |
229 | ((__psint_t)cur->item | 1); | |
230 | } | |
231 | } | |
232 | ||
249a8c11 | 233 | /* |
16b59029 DC |
234 | * Find the first item in the AIL with the given @lsn by searching in ascending |
235 | * LSN order and initialise the cursor to point to the next item for a | |
236 | * ascending traversal. Pass a @lsn of zero to initialise the cursor to the | |
237 | * first item in the AIL. Returns NULL if the list is empty. | |
249a8c11 | 238 | */ |
5b00f14f DC |
239 | xfs_log_item_t * |
240 | xfs_trans_ail_cursor_first( | |
27d8d5fe DC |
241 | struct xfs_ail *ailp, |
242 | struct xfs_ail_cursor *cur, | |
243 | xfs_lsn_t lsn) | |
249a8c11 | 244 | { |
27d8d5fe | 245 | xfs_log_item_t *lip; |
249a8c11 | 246 | |
5b00f14f | 247 | xfs_trans_ail_cursor_init(ailp, cur); |
16b59029 DC |
248 | |
249 | if (lsn == 0) { | |
250 | lip = xfs_ail_min(ailp); | |
5b00f14f | 251 | goto out; |
16b59029 | 252 | } |
249a8c11 | 253 | |
27d8d5fe | 254 | list_for_each_entry(lip, &ailp->xa_ail, li_ail) { |
5b00f14f | 255 | if (XFS_LSN_CMP(lip->li_lsn, lsn) >= 0) |
7ee49acf | 256 | goto out; |
535f6b37 | 257 | } |
16b59029 DC |
258 | return NULL; |
259 | ||
5b00f14f | 260 | out: |
16b59029 DC |
261 | if (lip) |
262 | cur->item = xfs_ail_next(ailp, lip); | |
5b00f14f | 263 | return lip; |
249a8c11 DC |
264 | } |
265 | ||
1d8c95a3 DC |
266 | static struct xfs_log_item * |
267 | __xfs_trans_ail_cursor_last( | |
268 | struct xfs_ail *ailp, | |
269 | xfs_lsn_t lsn) | |
270 | { | |
271 | xfs_log_item_t *lip; | |
272 | ||
273 | list_for_each_entry_reverse(lip, &ailp->xa_ail, li_ail) { | |
274 | if (XFS_LSN_CMP(lip->li_lsn, lsn) <= 0) | |
275 | return lip; | |
276 | } | |
277 | return NULL; | |
278 | } | |
279 | ||
280 | /* | |
16b59029 DC |
281 | * Find the last item in the AIL with the given @lsn by searching in descending |
282 | * LSN order and initialise the cursor to point to that item. If there is no | |
283 | * item with the value of @lsn, then it sets the cursor to the last item with an | |
284 | * LSN lower than @lsn. Returns NULL if the list is empty. | |
1d8c95a3 DC |
285 | */ |
286 | struct xfs_log_item * | |
287 | xfs_trans_ail_cursor_last( | |
288 | struct xfs_ail *ailp, | |
289 | struct xfs_ail_cursor *cur, | |
290 | xfs_lsn_t lsn) | |
291 | { | |
292 | xfs_trans_ail_cursor_init(ailp, cur); | |
293 | cur->item = __xfs_trans_ail_cursor_last(ailp, lsn); | |
294 | return cur->item; | |
295 | } | |
296 | ||
297 | /* | |
16b59029 | 298 | * Splice the log item list into the AIL at the given LSN. We splice to the |
1d8c95a3 DC |
299 | * tail of the given LSN to maintain insert order for push traversals. The |
300 | * cursor is optional, allowing repeated updates to the same LSN to avoid | |
e44f4112 | 301 | * repeated traversals. This should not be called with an empty list. |
cd4a3c50 DC |
302 | */ |
303 | static void | |
304 | xfs_ail_splice( | |
1d8c95a3 DC |
305 | struct xfs_ail *ailp, |
306 | struct xfs_ail_cursor *cur, | |
307 | struct list_head *list, | |
308 | xfs_lsn_t lsn) | |
cd4a3c50 | 309 | { |
e44f4112 AE |
310 | struct xfs_log_item *lip; |
311 | ||
312 | ASSERT(!list_empty(list)); | |
cd4a3c50 | 313 | |
1d8c95a3 | 314 | /* |
e44f4112 AE |
315 | * Use the cursor to determine the insertion point if one is |
316 | * provided. If not, or if the one we got is not valid, | |
317 | * find the place in the AIL where the items belong. | |
1d8c95a3 | 318 | */ |
e44f4112 AE |
319 | lip = cur ? cur->item : NULL; |
320 | if (!lip || (__psint_t) lip & 1) | |
1d8c95a3 DC |
321 | lip = __xfs_trans_ail_cursor_last(ailp, lsn); |
322 | ||
e44f4112 AE |
323 | /* |
324 | * If a cursor is provided, we know we're processing the AIL | |
325 | * in lsn order, and future items to be spliced in will | |
326 | * follow the last one being inserted now. Update the | |
327 | * cursor to point to that last item, now while we have a | |
328 | * reliable pointer to it. | |
329 | */ | |
330 | if (cur) | |
331 | cur->item = list_entry(list->prev, struct xfs_log_item, li_ail); | |
cd4a3c50 | 332 | |
1d8c95a3 | 333 | /* |
e44f4112 AE |
334 | * Finally perform the splice. Unless the AIL was empty, |
335 | * lip points to the item in the AIL _after_ which the new | |
336 | * items should go. If lip is null the AIL was empty, so | |
337 | * the new items go at the head of the AIL. | |
1d8c95a3 | 338 | */ |
e44f4112 AE |
339 | if (lip) |
340 | list_splice(list, &lip->li_ail); | |
341 | else | |
342 | list_splice(list, &ailp->xa_ail); | |
cd4a3c50 DC |
343 | } |
344 | ||
345 | /* | |
346 | * Delete the given item from the AIL. Return a pointer to the item. | |
347 | */ | |
348 | static void | |
349 | xfs_ail_delete( | |
350 | struct xfs_ail *ailp, | |
351 | xfs_log_item_t *lip) | |
352 | { | |
353 | xfs_ail_check(ailp, lip); | |
354 | list_del(&lip->li_ail); | |
355 | xfs_trans_ail_cursor_clear(ailp, lip); | |
356 | } | |
357 | ||
0030807c CH |
358 | static long |
359 | xfsaild_push( | |
360 | struct xfs_ail *ailp) | |
249a8c11 | 361 | { |
9e7004e7 | 362 | xfs_mount_t *mp = ailp->xa_mount; |
af3e4022 | 363 | struct xfs_ail_cursor cur; |
9e7004e7 DC |
364 | xfs_log_item_t *lip; |
365 | xfs_lsn_t lsn; | |
fe0da767 | 366 | xfs_lsn_t target; |
43ff2122 | 367 | long tout; |
9e7004e7 | 368 | int stuck = 0; |
43ff2122 | 369 | int flushing = 0; |
9e7004e7 | 370 | int count = 0; |
1da177e4 | 371 | |
670ce93f | 372 | /* |
43ff2122 CH |
373 | * If we encountered pinned items or did not finish writing out all |
374 | * buffers the last time we ran, force the log first and wait for it | |
375 | * before pushing again. | |
670ce93f | 376 | */ |
43ff2122 CH |
377 | if (ailp->xa_log_flush && ailp->xa_last_pushed_lsn == 0 && |
378 | (!list_empty_careful(&ailp->xa_buf_list) || | |
379 | xfs_ail_min_lsn(ailp))) { | |
670ce93f | 380 | ailp->xa_log_flush = 0; |
43ff2122 | 381 | |
670ce93f DC |
382 | XFS_STATS_INC(xs_push_ail_flush); |
383 | xfs_log_force(mp, XFS_LOG_SYNC); | |
670ce93f DC |
384 | } |
385 | ||
43ff2122 | 386 | spin_lock(&ailp->xa_lock); |
af3e4022 | 387 | lip = xfs_trans_ail_cursor_first(ailp, &cur, ailp->xa_last_pushed_lsn); |
211e4d43 | 388 | if (!lip) { |
1da177e4 | 389 | /* |
43ff2122 CH |
390 | * If the AIL is empty or our push has reached the end we are |
391 | * done now. | |
1da177e4 | 392 | */ |
af3e4022 | 393 | xfs_trans_ail_cursor_done(ailp, &cur); |
c7e8f268 | 394 | spin_unlock(&ailp->xa_lock); |
9e7004e7 | 395 | goto out_done; |
1da177e4 LT |
396 | } |
397 | ||
398 | XFS_STATS_INC(xs_push_ail); | |
399 | ||
249a8c11 | 400 | lsn = lip->li_lsn; |
211e4d43 | 401 | target = ailp->xa_target; |
50e86686 | 402 | while ((XFS_LSN_CMP(lip->li_lsn, target) <= 0)) { |
249a8c11 | 403 | int lock_result; |
43ff2122 | 404 | |
1da177e4 | 405 | /* |
43ff2122 CH |
406 | * Note that IOP_PUSH may unlock and reacquire the AIL lock. We |
407 | * rely on the AIL cursor implementation to be able to deal with | |
408 | * the dropped lock. | |
1da177e4 | 409 | */ |
43ff2122 | 410 | lock_result = IOP_PUSH(lip, &ailp->xa_buf_list); |
1da177e4 | 411 | switch (lock_result) { |
249a8c11 | 412 | case XFS_ITEM_SUCCESS: |
1da177e4 | 413 | XFS_STATS_INC(xs_push_ail_success); |
9e4c109a CH |
414 | trace_xfs_ail_push(lip); |
415 | ||
0bf6a5bd | 416 | ailp->xa_last_pushed_lsn = lsn; |
1da177e4 LT |
417 | break; |
418 | ||
43ff2122 CH |
419 | case XFS_ITEM_FLUSHING: |
420 | /* | |
421 | * The item or its backing buffer is already beeing | |
422 | * flushed. The typical reason for that is that an | |
423 | * inode buffer is locked because we already pushed the | |
424 | * updates to it as part of inode clustering. | |
425 | * | |
426 | * We do not want to to stop flushing just because lots | |
427 | * of items are already beeing flushed, but we need to | |
428 | * re-try the flushing relatively soon if most of the | |
429 | * AIL is beeing flushed. | |
430 | */ | |
431 | XFS_STATS_INC(xs_push_ail_flushing); | |
432 | trace_xfs_ail_flushing(lip); | |
433 | ||
434 | flushing++; | |
435 | ailp->xa_last_pushed_lsn = lsn; | |
1da177e4 LT |
436 | break; |
437 | ||
249a8c11 | 438 | case XFS_ITEM_PINNED: |
1da177e4 | 439 | XFS_STATS_INC(xs_push_ail_pinned); |
9e4c109a CH |
440 | trace_xfs_ail_pinned(lip); |
441 | ||
249a8c11 | 442 | stuck++; |
670ce93f | 443 | ailp->xa_log_flush++; |
1da177e4 | 444 | break; |
249a8c11 | 445 | case XFS_ITEM_LOCKED: |
1da177e4 | 446 | XFS_STATS_INC(xs_push_ail_locked); |
9e4c109a | 447 | trace_xfs_ail_locked(lip); |
43ff2122 | 448 | |
249a8c11 | 449 | stuck++; |
1da177e4 | 450 | break; |
249a8c11 | 451 | default: |
1da177e4 LT |
452 | ASSERT(0); |
453 | break; | |
454 | } | |
455 | ||
249a8c11 | 456 | count++; |
1da177e4 | 457 | |
249a8c11 DC |
458 | /* |
459 | * Are there too many items we can't do anything with? | |
43ff2122 | 460 | * |
249a8c11 DC |
461 | * If we we are skipping too many items because we can't flush |
462 | * them or they are already being flushed, we back off and | |
463 | * given them time to complete whatever operation is being | |
464 | * done. i.e. remove pressure from the AIL while we can't make | |
465 | * progress so traversals don't slow down further inserts and | |
466 | * removals to/from the AIL. | |
467 | * | |
468 | * The value of 100 is an arbitrary magic number based on | |
469 | * observation. | |
470 | */ | |
471 | if (stuck > 100) | |
472 | break; | |
473 | ||
af3e4022 | 474 | lip = xfs_trans_ail_cursor_next(ailp, &cur); |
249a8c11 DC |
475 | if (lip == NULL) |
476 | break; | |
249a8c11 | 477 | lsn = lip->li_lsn; |
1da177e4 | 478 | } |
af3e4022 | 479 | xfs_trans_ail_cursor_done(ailp, &cur); |
c7e8f268 | 480 | spin_unlock(&ailp->xa_lock); |
1da177e4 | 481 | |
43ff2122 CH |
482 | if (xfs_buf_delwri_submit_nowait(&ailp->xa_buf_list)) |
483 | ailp->xa_log_flush++; | |
d808f617 | 484 | |
43ff2122 | 485 | if (!count || XFS_LSN_CMP(lsn, target) >= 0) { |
9e7004e7 | 486 | out_done: |
92d9cd10 | 487 | /* |
43ff2122 CH |
488 | * We reached the target or the AIL is empty, so wait a bit |
489 | * longer for I/O to complete and remove pushed items from the | |
490 | * AIL before we start the next scan from the start of the AIL. | |
92d9cd10 | 491 | */ |
453eac8a | 492 | tout = 50; |
0bf6a5bd | 493 | ailp->xa_last_pushed_lsn = 0; |
43ff2122 | 494 | } else if (((stuck + flushing) * 100) / count > 90) { |
249a8c11 | 495 | /* |
43ff2122 CH |
496 | * Either there is a lot of contention on the AIL or we are |
497 | * stuck due to operations in progress. "Stuck" in this case | |
498 | * is defined as >90% of the items we tried to push were stuck. | |
249a8c11 DC |
499 | * |
500 | * Backoff a bit more to allow some I/O to complete before | |
43ff2122 CH |
501 | * restarting from the start of the AIL. This prevents us from |
502 | * spinning on the same items, and if they are pinned will all | |
503 | * the restart to issue a log force to unpin the stuck items. | |
249a8c11 | 504 | */ |
453eac8a | 505 | tout = 20; |
670ce93f | 506 | ailp->xa_last_pushed_lsn = 0; |
43ff2122 CH |
507 | } else { |
508 | /* | |
509 | * Assume we have more work to do in a short while. | |
510 | */ | |
511 | tout = 10; | |
1da177e4 | 512 | } |
0bf6a5bd | 513 | |
0030807c CH |
514 | return tout; |
515 | } | |
516 | ||
517 | static int | |
518 | xfsaild( | |
519 | void *data) | |
520 | { | |
521 | struct xfs_ail *ailp = data; | |
522 | long tout = 0; /* milliseconds */ | |
523 | ||
43ff2122 CH |
524 | current->flags |= PF_MEMALLOC; |
525 | ||
0030807c CH |
526 | while (!kthread_should_stop()) { |
527 | if (tout && tout <= 20) | |
528 | __set_current_state(TASK_KILLABLE); | |
529 | else | |
530 | __set_current_state(TASK_INTERRUPTIBLE); | |
531 | schedule_timeout(tout ? | |
532 | msecs_to_jiffies(tout) : MAX_SCHEDULE_TIMEOUT); | |
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 | ||
661 | xfs_ail_delete(ailp, lip); | |
662 | if (mlip == lip) | |
663 | mlip_changed = 1; | |
664 | } else { | |
665 | lip->li_flags |= XFS_LI_IN_AIL; | |
666 | } | |
667 | lip->li_lsn = lsn; | |
668 | list_add(&lip->li_ail, &tmp); | |
669 | } | |
670 | ||
e44f4112 AE |
671 | if (!list_empty(&tmp)) |
672 | xfs_ail_splice(ailp, cur, &tmp, lsn); | |
0e57f6a3 | 673 | |
1c304625 CH |
674 | if (mlip_changed) { |
675 | if (!XFS_FORCED_SHUTDOWN(ailp->xa_mount)) | |
676 | xlog_assign_tail_lsn_locked(ailp->xa_mount); | |
677 | spin_unlock(&ailp->xa_lock); | |
678 | ||
cfb7cdca | 679 | xfs_log_space_wake(ailp->xa_mount); |
1c304625 CH |
680 | } else { |
681 | spin_unlock(&ailp->xa_lock); | |
0e57f6a3 | 682 | } |
0e57f6a3 DC |
683 | } |
684 | ||
30136832 DC |
685 | /* |
686 | * xfs_trans_ail_delete_bulk - remove multiple log items from the AIL | |
687 | * | |
688 | * @xfs_trans_ail_delete_bulk takes an array of log items that all need to | |
689 | * removed from the AIL. The caller is already holding the AIL lock, and done | |
690 | * all the checks necessary to ensure the items passed in via @log_items are | |
691 | * ready for deletion. This includes checking that the items are in the AIL. | |
692 | * | |
693 | * For each log item to be removed, unlink it from the AIL, clear the IN_AIL | |
694 | * flag from the item and reset the item's lsn to 0. If we remove the first | |
695 | * item in the AIL, update the log tail to match the new minimum LSN in the | |
696 | * AIL. | |
697 | * | |
698 | * This function will not drop the AIL lock until all items are removed from | |
699 | * the AIL to minimise the amount of lock traffic on the AIL. This does not | |
700 | * greatly increase the AIL hold time, but does significantly reduce the amount | |
701 | * of traffic on the lock, especially during IO completion. | |
702 | * | |
703 | * This function must be called with the AIL lock held. The lock is dropped | |
704 | * before returning. | |
705 | */ | |
706 | void | |
707 | xfs_trans_ail_delete_bulk( | |
708 | struct xfs_ail *ailp, | |
709 | struct xfs_log_item **log_items, | |
710 | int nr_items) __releases(ailp->xa_lock) | |
711 | { | |
712 | xfs_log_item_t *mlip; | |
30136832 DC |
713 | int mlip_changed = 0; |
714 | int i; | |
715 | ||
716 | mlip = xfs_ail_min(ailp); | |
717 | ||
718 | for (i = 0; i < nr_items; i++) { | |
719 | struct xfs_log_item *lip = log_items[i]; | |
720 | if (!(lip->li_flags & XFS_LI_IN_AIL)) { | |
721 | struct xfs_mount *mp = ailp->xa_mount; | |
722 | ||
723 | spin_unlock(&ailp->xa_lock); | |
724 | if (!XFS_FORCED_SHUTDOWN(mp)) { | |
6a19d939 | 725 | xfs_alert_tag(mp, XFS_PTAG_AILDELETE, |
30136832 DC |
726 | "%s: attempting to delete a log item that is not in the AIL", |
727 | __func__); | |
728 | xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE); | |
729 | } | |
730 | return; | |
731 | } | |
732 | ||
733 | xfs_ail_delete(ailp, lip); | |
734 | lip->li_flags &= ~XFS_LI_IN_AIL; | |
735 | lip->li_lsn = 0; | |
736 | if (mlip == lip) | |
737 | mlip_changed = 1; | |
738 | } | |
739 | ||
1c304625 CH |
740 | if (mlip_changed) { |
741 | if (!XFS_FORCED_SHUTDOWN(ailp->xa_mount)) | |
742 | xlog_assign_tail_lsn_locked(ailp->xa_mount); | |
211e4d43 CH |
743 | if (list_empty(&ailp->xa_ail)) |
744 | wake_up_all(&ailp->xa_empty); | |
1c304625 CH |
745 | spin_unlock(&ailp->xa_lock); |
746 | ||
cfb7cdca | 747 | xfs_log_space_wake(ailp->xa_mount); |
1c304625 CH |
748 | } else { |
749 | spin_unlock(&ailp->xa_lock); | |
30136832 | 750 | } |
30136832 | 751 | } |
1da177e4 | 752 | |
1da177e4 LT |
753 | /* |
754 | * The active item list (AIL) is a doubly linked list of log | |
755 | * items sorted by ascending lsn. The base of the list is | |
756 | * a forw/back pointer pair embedded in the xfs mount structure. | |
757 | * The base is initialized with both pointers pointing to the | |
758 | * base. This case always needs to be distinguished, because | |
759 | * the base has no lsn to look at. We almost always insert | |
760 | * at the end of the list, so on inserts we search from the | |
761 | * end of the list to find where the new item belongs. | |
762 | */ | |
763 | ||
764 | /* | |
765 | * Initialize the doubly linked list to point only to itself. | |
766 | */ | |
249a8c11 | 767 | int |
1da177e4 LT |
768 | xfs_trans_ail_init( |
769 | xfs_mount_t *mp) | |
770 | { | |
82fa9012 DC |
771 | struct xfs_ail *ailp; |
772 | ||
773 | ailp = kmem_zalloc(sizeof(struct xfs_ail), KM_MAYFAIL); | |
774 | if (!ailp) | |
775 | return ENOMEM; | |
776 | ||
777 | ailp->xa_mount = mp; | |
778 | INIT_LIST_HEAD(&ailp->xa_ail); | |
af3e4022 | 779 | INIT_LIST_HEAD(&ailp->xa_cursors); |
c7e8f268 | 780 | spin_lock_init(&ailp->xa_lock); |
43ff2122 | 781 | INIT_LIST_HEAD(&ailp->xa_buf_list); |
211e4d43 | 782 | init_waitqueue_head(&ailp->xa_empty); |
0030807c CH |
783 | |
784 | ailp->xa_task = kthread_run(xfsaild, ailp, "xfsaild/%s", | |
785 | ailp->xa_mount->m_fsname); | |
786 | if (IS_ERR(ailp->xa_task)) | |
787 | goto out_free_ailp; | |
788 | ||
27d8d5fe DC |
789 | mp->m_ail = ailp; |
790 | return 0; | |
0030807c CH |
791 | |
792 | out_free_ailp: | |
793 | kmem_free(ailp); | |
794 | return ENOMEM; | |
249a8c11 DC |
795 | } |
796 | ||
797 | void | |
798 | xfs_trans_ail_destroy( | |
799 | xfs_mount_t *mp) | |
800 | { | |
82fa9012 DC |
801 | struct xfs_ail *ailp = mp->m_ail; |
802 | ||
0030807c | 803 | kthread_stop(ailp->xa_task); |
82fa9012 | 804 | kmem_free(ailp); |
1da177e4 | 805 | } |