1/* 2 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc. 3 * Copyright (c) 2008 Dave Chinner 4 * All Rights Reserved. 5 * 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 8 * published by the Free Software Foundation. 9 * 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. 14 * 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 18 */ 19#include "xfs.h" 20#include "xfs_fs.h" 21#include "xfs_format.h" 22#include "xfs_log_format.h" 23#include "xfs_trans_resv.h" 24#include "xfs_mount.h" 25#include "xfs_trans.h" 26#include "xfs_trans_priv.h" 27#include "xfs_trace.h" 28#include "xfs_error.h" 29#include "xfs_log.h" 30 31#ifdef DEBUG 32/* 33 * Check that the list is sorted as it should be. 34 */ 35STATIC void 36xfs_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 58} 59#else /* !DEBUG */ 60#define xfs_ail_check(a,l) 61#endif /* DEBUG */ 62 63/* 64 * Return a pointer to the last item in the AIL. If the AIL is empty, then 65 * return NULL. 66 */ 67static xfs_log_item_t * 68xfs_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 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 */ 81static xfs_log_item_t * 82xfs_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} 91 92/* 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. 96 * 97 * We need the AIL lock in order to get a coherent read of the lsn of the last 98 * item in the AIL. 99 */ 100xfs_lsn_t 101xfs_ail_min_lsn( 102 struct xfs_ail *ailp) 103{ 104 xfs_lsn_t lsn = 0; 105 xfs_log_item_t *lip; 106 107 spin_lock(&ailp->xa_lock); 108 lip = xfs_ail_min(ailp); 109 if (lip) 110 lsn = lip->li_lsn; 111 spin_unlock(&ailp->xa_lock); 112 113 return lsn; 114} 115 116/* 117 * Return the maximum lsn held in the AIL, or zero if the AIL is empty. 118 */ 119static xfs_lsn_t 120xfs_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} 134 135/* 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. 141 */ 142STATIC void 143xfs_trans_ail_cursor_init( 144 struct xfs_ail *ailp, 145 struct xfs_ail_cursor *cur) 146{ 147 cur->item = NULL; 148 list_add_tail(&cur->list, &ailp->xa_cursors); 149} 150 151/* 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. 154 */ 155struct xfs_log_item * 156xfs_trans_ail_cursor_next( 157 struct xfs_ail *ailp, 158 struct xfs_ail_cursor *cur) 159{ 160 struct xfs_log_item *lip = cur->item; 161 162 if ((__psint_t)lip & 1) 163 lip = xfs_ail_min(ailp); 164 if (lip) 165 cur->item = xfs_ail_next(ailp, lip); 166 return lip; 167} 168 169/* 170 * When the traversal is complete, we need to remove the cursor from the list 171 * of traversing cursors. 172 */ 173void 174xfs_trans_ail_cursor_done( 175 struct xfs_ail_cursor *cur) 176{ 177 cur->item = NULL; 178 list_del_init(&cur->list); 179} 180 181/* 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. 188 */ 189STATIC void 190xfs_trans_ail_cursor_clear( 191 struct xfs_ail *ailp, 192 struct xfs_log_item *lip) 193{ 194 struct xfs_ail_cursor *cur; 195 196 list_for_each_entry(cur, &ailp->xa_cursors, list) { 197 if (cur->item == lip) 198 cur->item = (struct xfs_log_item *) 199 ((__psint_t)cur->item | 1); 200 } 201} 202 203/* 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. 208 */ 209xfs_log_item_t * 210xfs_trans_ail_cursor_first( 211 struct xfs_ail *ailp, 212 struct xfs_ail_cursor *cur, 213 xfs_lsn_t lsn) 214{ 215 xfs_log_item_t *lip; 216 217 xfs_trans_ail_cursor_init(ailp, cur); 218 219 if (lsn == 0) { 220 lip = xfs_ail_min(ailp); 221 goto out; 222 } 223 224 list_for_each_entry(lip, &ailp->xa_ail, li_ail) { 225 if (XFS_LSN_CMP(lip->li_lsn, lsn) >= 0) 226 goto out; 227 } 228 return NULL; 229 230out: 231 if (lip) 232 cur->item = xfs_ail_next(ailp, lip); 233 return lip; 234} 235 236static 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/* 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. 255 */ 256struct xfs_log_item * 257xfs_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/* 268 * Splice the log item list into the AIL at the given LSN. We splice to the 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 271 * repeated traversals. This should not be called with an empty list. 272 */ 273static void 274xfs_ail_splice( 275 struct xfs_ail *ailp, 276 struct xfs_ail_cursor *cur, 277 struct list_head *list, 278 xfs_lsn_t lsn) 279{ 280 struct xfs_log_item *lip; 281 282 ASSERT(!list_empty(list)); 283 284 /* 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. 288 */ 289 lip = cur ? cur->item : NULL; 290 if (!lip || (__psint_t) lip & 1) 291 lip = __xfs_trans_ail_cursor_last(ailp, lsn); 292 293 /* 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); 302 303 /* 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. 308 */ 309 if (lip) 310 list_splice(list, &lip->li_ail); 311 else 312 list_splice(list, &ailp->xa_ail); 313} 314 315/* 316 * Delete the given item from the AIL. Return a pointer to the item. 317 */ 318static void 319xfs_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 328static long 329xfsaild_push( 330 struct xfs_ail *ailp) 331{ 332 xfs_mount_t *mp = ailp->xa_mount; 333 struct xfs_ail_cursor cur; 334 xfs_log_item_t *lip; 335 xfs_lsn_t lsn; 336 xfs_lsn_t target; 337 long tout; 338 int stuck = 0; 339 int flushing = 0; 340 int count = 0; 341 342 /* 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. 346 */ 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))) { 350 ailp->xa_log_flush = 0; 351 352 XFS_STATS_INC(xs_push_ail_flush); 353 xfs_log_force(mp, XFS_LOG_SYNC); 354 } 355 356 spin_lock(&ailp->xa_lock); 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; 362 363 lip = xfs_trans_ail_cursor_first(ailp, &cur, ailp->xa_last_pushed_lsn); 364 if (!lip) { 365 /* 366 * If the AIL is empty or our push has reached the end we are 367 * done now. 368 */ 369 xfs_trans_ail_cursor_done(&cur); 370 spin_unlock(&ailp->xa_lock); 371 goto out_done; 372 } 373 374 XFS_STATS_INC(xs_push_ail); 375 376 lsn = lip->li_lsn; 377 while ((XFS_LSN_CMP(lip->li_lsn, target) <= 0)) { 378 int lock_result; 379 380 /* 381 * Note that iop_push may unlock and reacquire the AIL lock. We 382 * rely on the AIL cursor implementation to be able to deal with 383 * the dropped lock. 384 */ 385 lock_result = lip->li_ops->iop_push(lip, &ailp->xa_buf_list); 386 switch (lock_result) { 387 case XFS_ITEM_SUCCESS: 388 XFS_STATS_INC(xs_push_ail_success); 389 trace_xfs_ail_push(lip); 390 391 ailp->xa_last_pushed_lsn = lsn; 392 break; 393 394 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 */ 406 XFS_STATS_INC(xs_push_ail_flushing); 407 trace_xfs_ail_flushing(lip); 408 409 flushing++; 410 ailp->xa_last_pushed_lsn = lsn; 411 break; 412 413 case XFS_ITEM_PINNED: 414 XFS_STATS_INC(xs_push_ail_pinned); 415 trace_xfs_ail_pinned(lip); 416 417 stuck++; 418 ailp->xa_log_flush++; 419 break; 420 case XFS_ITEM_LOCKED: 421 XFS_STATS_INC(xs_push_ail_locked); 422 trace_xfs_ail_locked(lip); 423 424 stuck++; 425 break; 426 default: 427 ASSERT(0); 428 break; 429 } 430 431 count++; 432 433 /* 434 * Are there too many items we can't do anything with? 435 * 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; 448 449 lip = xfs_trans_ail_cursor_next(ailp, &cur); 450 if (lip == NULL) 451 break; 452 lsn = lip->li_lsn; 453 } 454 xfs_trans_ail_cursor_done(&cur); 455 spin_unlock(&ailp->xa_lock); 456 457 if (xfs_buf_delwri_submit_nowait(&ailp->xa_buf_list)) 458 ailp->xa_log_flush++; 459 460 if (!count || XFS_LSN_CMP(lsn, target) >= 0) { 461out_done: 462 /* 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. 466 */ 467 tout = 50; 468 ailp->xa_last_pushed_lsn = 0; 469 } else if (((stuck + flushing) * 100) / count > 90) { 470 /* 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. 474 * 475 * Backoff a bit more to allow some I/O to complete before 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. 479 */ 480 tout = 20; 481 ailp->xa_last_pushed_lsn = 0; 482 } else { 483 /* 484 * Assume we have more work to do in a short while. 485 */ 486 tout = 10; 487 } 488 489 return tout; 490} 491 492static int 493xfsaild( 494 void *data) 495{ 496 struct xfs_ail *ailp = data; 497 long tout = 0; /* milliseconds */ 498 499 current->flags |= PF_MEMALLOC; 500 501 while (!kthread_should_stop()) { 502 if (tout && tout <= 20) 503 __set_current_state(TASK_KILLABLE); 504 else 505 __set_current_state(TASK_INTERRUPTIBLE); 506 507 spin_lock(&ailp->xa_lock); 508 509 /* 510 * Idle if the AIL is empty and we are not racing with a target 511 * update. We check the AIL after we set the task to a sleep 512 * state to guarantee that we either catch an xa_target update 513 * or that a wake_up resets the state to TASK_RUNNING. 514 * Otherwise, we run the risk of sleeping indefinitely. 515 * 516 * The barrier matches the xa_target update in xfs_ail_push(). 517 */ 518 smp_rmb(); 519 if (!xfs_ail_min(ailp) && 520 ailp->xa_target == ailp->xa_target_prev) { 521 spin_unlock(&ailp->xa_lock); 522 schedule(); 523 tout = 0; 524 continue; 525 } 526 spin_unlock(&ailp->xa_lock); 527 528 if (tout) 529 schedule_timeout(msecs_to_jiffies(tout)); 530 531 __set_current_state(TASK_RUNNING); 532 533 try_to_freeze(); 534 535 tout = xfsaild_push(ailp); 536 } 537 538 return 0; 539} 540 541/* 542 * This routine is called to move the tail of the AIL forward. It does this by 543 * trying to flush items in the AIL whose lsns are below the given 544 * threshold_lsn. 545 * 546 * The push is run asynchronously in a workqueue, which means the caller needs 547 * to handle waiting on the async flush for space to become available. 548 * We don't want to interrupt any push that is in progress, hence we only queue 549 * work if we set the pushing bit approriately. 550 * 551 * We do this unlocked - we only need to know whether there is anything in the 552 * AIL at the time we are called. We don't need to access the contents of 553 * any of the objects, so the lock is not needed. 554 */ 555void 556xfs_ail_push( 557 struct xfs_ail *ailp, 558 xfs_lsn_t threshold_lsn) 559{ 560 xfs_log_item_t *lip; 561 562 lip = xfs_ail_min(ailp); 563 if (!lip || XFS_FORCED_SHUTDOWN(ailp->xa_mount) || 564 XFS_LSN_CMP(threshold_lsn, ailp->xa_target) <= 0) 565 return; 566 567 /* 568 * Ensure that the new target is noticed in push code before it clears 569 * the XFS_AIL_PUSHING_BIT. 570 */ 571 smp_wmb(); 572 xfs_trans_ail_copy_lsn(ailp, &ailp->xa_target, &threshold_lsn); 573 smp_wmb(); 574 575 wake_up_process(ailp->xa_task); 576} 577 578/* 579 * Push out all items in the AIL immediately 580 */ 581void 582xfs_ail_push_all( 583 struct xfs_ail *ailp) 584{ 585 xfs_lsn_t threshold_lsn = xfs_ail_max_lsn(ailp); 586 587 if (threshold_lsn) 588 xfs_ail_push(ailp, threshold_lsn); 589} 590 591/* 592 * Push out all items in the AIL immediately and wait until the AIL is empty. 593 */ 594void 595xfs_ail_push_all_sync( 596 struct xfs_ail *ailp) 597{ 598 struct xfs_log_item *lip; 599 DEFINE_WAIT(wait); 600 601 spin_lock(&ailp->xa_lock); 602 while ((lip = xfs_ail_max(ailp)) != NULL) { 603 prepare_to_wait(&ailp->xa_empty, &wait, TASK_UNINTERRUPTIBLE); 604 ailp->xa_target = lip->li_lsn; 605 wake_up_process(ailp->xa_task); 606 spin_unlock(&ailp->xa_lock); 607 schedule(); 608 spin_lock(&ailp->xa_lock); 609 } 610 spin_unlock(&ailp->xa_lock); 611 612 finish_wait(&ailp->xa_empty, &wait); 613} 614 615/* 616 * xfs_trans_ail_update - bulk AIL insertion operation. 617 * 618 * @xfs_trans_ail_update takes an array of log items that all need to be 619 * positioned at the same LSN in the AIL. If an item is not in the AIL, it will 620 * be added. Otherwise, it will be repositioned by removing it and re-adding 621 * it to the AIL. If we move the first item in the AIL, update the log tail to 622 * match the new minimum LSN in the AIL. 623 * 624 * This function takes the AIL lock once to execute the update operations on 625 * all the items in the array, and as such should not be called with the AIL 626 * lock held. As a result, once we have the AIL lock, we need to check each log 627 * item LSN to confirm it needs to be moved forward in the AIL. 628 * 629 * To optimise the insert operation, we delete all the items from the AIL in 630 * the first pass, moving them into a temporary list, then splice the temporary 631 * list into the correct position in the AIL. This avoids needing to do an 632 * insert operation on every item. 633 * 634 * This function must be called with the AIL lock held. The lock is dropped 635 * before returning. 636 */ 637void 638xfs_trans_ail_update_bulk( 639 struct xfs_ail *ailp, 640 struct xfs_ail_cursor *cur, 641 struct xfs_log_item **log_items, 642 int nr_items, 643 xfs_lsn_t lsn) __releases(ailp->xa_lock) 644{ 645 xfs_log_item_t *mlip; 646 int mlip_changed = 0; 647 int i; 648 LIST_HEAD(tmp); 649 650 ASSERT(nr_items > 0); /* Not required, but true. */ 651 mlip = xfs_ail_min(ailp); 652 653 for (i = 0; i < nr_items; i++) { 654 struct xfs_log_item *lip = log_items[i]; 655 if (lip->li_flags & XFS_LI_IN_AIL) { 656 /* check if we really need to move the item */ 657 if (XFS_LSN_CMP(lsn, lip->li_lsn) <= 0) 658 continue; 659 660 trace_xfs_ail_move(lip, lip->li_lsn, lsn); 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 trace_xfs_ail_insert(lip, 0, lsn); 667 } 668 lip->li_lsn = lsn; 669 list_add(&lip->li_ail, &tmp); 670 } 671 672 if (!list_empty(&tmp)) 673 xfs_ail_splice(ailp, cur, &tmp, lsn); 674 675 if (mlip_changed) { 676 if (!XFS_FORCED_SHUTDOWN(ailp->xa_mount)) 677 xlog_assign_tail_lsn_locked(ailp->xa_mount); 678 spin_unlock(&ailp->xa_lock); 679 680 xfs_log_space_wake(ailp->xa_mount); 681 } else { 682 spin_unlock(&ailp->xa_lock); 683 } 684} 685 686/* 687 * xfs_trans_ail_delete_bulk - remove multiple log items from the AIL 688 * 689 * @xfs_trans_ail_delete_bulk takes an array of log items that all need to 690 * removed from the AIL. The caller is already holding the AIL lock, and done 691 * all the checks necessary to ensure the items passed in via @log_items are 692 * ready for deletion. This includes checking that the items are in the AIL. 693 * 694 * For each log item to be removed, unlink it from the AIL, clear the IN_AIL 695 * flag from the item and reset the item's lsn to 0. If we remove the first 696 * item in the AIL, update the log tail to match the new minimum LSN in the 697 * AIL. 698 * 699 * This function will not drop the AIL lock until all items are removed from 700 * the AIL to minimise the amount of lock traffic on the AIL. This does not 701 * greatly increase the AIL hold time, but does significantly reduce the amount 702 * of traffic on the lock, especially during IO completion. 703 * 704 * This function must be called with the AIL lock held. The lock is dropped 705 * before returning. 706 */ 707void 708xfs_trans_ail_delete_bulk( 709 struct xfs_ail *ailp, 710 struct xfs_log_item **log_items, 711 int nr_items, 712 int shutdown_type) __releases(ailp->xa_lock) 713{ 714 xfs_log_item_t *mlip; 715 int mlip_changed = 0; 716 int i; 717 718 mlip = xfs_ail_min(ailp); 719 720 for (i = 0; i < nr_items; i++) { 721 struct xfs_log_item *lip = log_items[i]; 722 if (!(lip->li_flags & XFS_LI_IN_AIL)) { 723 struct xfs_mount *mp = ailp->xa_mount; 724 725 spin_unlock(&ailp->xa_lock); 726 if (!XFS_FORCED_SHUTDOWN(mp)) { 727 xfs_alert_tag(mp, XFS_PTAG_AILDELETE, 728 "%s: attempting to delete a log item that is not in the AIL", 729 __func__); 730 xfs_force_shutdown(mp, shutdown_type); 731 } 732 return; 733 } 734 735 trace_xfs_ail_delete(lip, mlip->li_lsn, lip->li_lsn); 736 xfs_ail_delete(ailp, lip); 737 lip->li_flags &= ~XFS_LI_IN_AIL; 738 lip->li_lsn = 0; 739 if (mlip == lip) 740 mlip_changed = 1; 741 } 742 743 if (mlip_changed) { 744 if (!XFS_FORCED_SHUTDOWN(ailp->xa_mount)) 745 xlog_assign_tail_lsn_locked(ailp->xa_mount); 746 if (list_empty(&ailp->xa_ail)) 747 wake_up_all(&ailp->xa_empty); 748 spin_unlock(&ailp->xa_lock); 749 750 xfs_log_space_wake(ailp->xa_mount); 751 } else { 752 spin_unlock(&ailp->xa_lock); 753 } 754} 755 756int 757xfs_trans_ail_init( 758 xfs_mount_t *mp) 759{ 760 struct xfs_ail *ailp; 761 762 ailp = kmem_zalloc(sizeof(struct xfs_ail), KM_MAYFAIL); 763 if (!ailp) 764 return -ENOMEM; 765 766 ailp->xa_mount = mp; 767 INIT_LIST_HEAD(&ailp->xa_ail); 768 INIT_LIST_HEAD(&ailp->xa_cursors); 769 spin_lock_init(&ailp->xa_lock); 770 INIT_LIST_HEAD(&ailp->xa_buf_list); 771 init_waitqueue_head(&ailp->xa_empty); 772 773 ailp->xa_task = kthread_run(xfsaild, ailp, "xfsaild/%s", 774 ailp->xa_mount->m_fsname); 775 if (IS_ERR(ailp->xa_task)) 776 goto out_free_ailp; 777 778 mp->m_ail = ailp; 779 return 0; 780 781out_free_ailp: 782 kmem_free(ailp); 783 return -ENOMEM; 784} 785 786void 787xfs_trans_ail_destroy( 788 xfs_mount_t *mp) 789{ 790 struct xfs_ail *ailp = mp->m_ail; 791 792 kthread_stop(ailp->xa_task); 793 kmem_free(ailp); 794} 795