diff options
Diffstat (limited to 'fs/xfs/libxfs/xfs_defer.c')
-rw-r--r-- | fs/xfs/libxfs/xfs_defer.c | 368 |
1 files changed, 286 insertions, 82 deletions
diff --git a/fs/xfs/libxfs/xfs_defer.c b/fs/xfs/libxfs/xfs_defer.c index 22557527cfdb..3a78a189ea01 100644 --- a/fs/xfs/libxfs/xfs_defer.c +++ b/fs/xfs/libxfs/xfs_defer.c @@ -16,6 +16,8 @@ #include "xfs_inode.h" #include "xfs_inode_item.h" #include "xfs_trace.h" +#include "xfs_icache.h" +#include "xfs_log.h" /* * Deferred Operations in XFS @@ -178,6 +180,19 @@ static const struct xfs_defer_op_type *defer_op_types[] = { [XFS_DEFER_OPS_TYPE_AGFL_FREE] = &xfs_agfl_free_defer_type, }; +static void +xfs_defer_create_intent( + struct xfs_trans *tp, + struct xfs_defer_pending *dfp, + bool sort) +{ + const struct xfs_defer_op_type *ops = defer_op_types[dfp->dfp_type]; + + if (!dfp->dfp_intent) + dfp->dfp_intent = ops->create_intent(tp, &dfp->dfp_work, + dfp->dfp_count, sort); +} + /* * For each pending item in the intake list, log its intent item and the * associated extents, then add the entire intake list to the end of @@ -187,17 +202,11 @@ STATIC void xfs_defer_create_intents( struct xfs_trans *tp) { - struct list_head *li; struct xfs_defer_pending *dfp; - const struct xfs_defer_op_type *ops; list_for_each_entry(dfp, &tp->t_dfops, dfp_list) { - ops = defer_op_types[dfp->dfp_type]; - dfp->dfp_intent = ops->create_intent(tp, dfp->dfp_count); trace_xfs_defer_create_intent(tp->t_mountp, dfp); - list_sort(tp->t_mountp, &dfp->dfp_work, ops->diff_items); - list_for_each(li, &dfp->dfp_work) - ops->log_item(tp, dfp->dfp_intent, li); + xfs_defer_create_intent(tp, dfp, true); } } @@ -234,10 +243,13 @@ xfs_defer_trans_roll( struct xfs_log_item *lip; struct xfs_buf *bplist[XFS_DEFER_OPS_NR_BUFS]; struct xfs_inode *iplist[XFS_DEFER_OPS_NR_INODES]; + unsigned int ordered = 0; /* bitmap */ int bpcount = 0, ipcount = 0; int i; int error; + BUILD_BUG_ON(NBBY * sizeof(ordered) < XFS_DEFER_OPS_NR_BUFS); + list_for_each_entry(lip, &tp->t_items, li_trans) { switch (lip->li_type) { case XFS_LI_BUF: @@ -248,7 +260,10 @@ xfs_defer_trans_roll( ASSERT(0); return -EFSCORRUPTED; } - xfs_trans_dirty_buf(tp, bli->bli_buf); + if (bli->bli_flags & XFS_BLI_ORDERED) + ordered |= (1U << bpcount); + else + xfs_trans_dirty_buf(tp, bli->bli_buf); bplist[bpcount++] = bli->bli_buf; } break; @@ -289,6 +304,8 @@ xfs_defer_trans_roll( /* Rejoin the buffers and dirty them so the log moves forward. */ for (i = 0; i < bpcount; i++) { xfs_trans_bjoin(tp, bplist[i]); + if (ordered & (1U << i)) + xfs_trans_ordered_buf(tp, bplist[i]); xfs_trans_bhold(tp, bplist[i]); } @@ -346,6 +363,106 @@ xfs_defer_cancel_list( } /* + * Prevent a log intent item from pinning the tail of the log by logging a + * done item to release the intent item; and then log a new intent item. + * The caller should provide a fresh transaction and roll it after we're done. + */ +static int +xfs_defer_relog( + struct xfs_trans **tpp, + struct list_head *dfops) +{ + struct xlog *log = (*tpp)->t_mountp->m_log; + struct xfs_defer_pending *dfp; + xfs_lsn_t threshold_lsn = NULLCOMMITLSN; + + + ASSERT((*tpp)->t_flags & XFS_TRANS_PERM_LOG_RES); + + list_for_each_entry(dfp, dfops, dfp_list) { + /* + * If the log intent item for this deferred op is not a part of + * the current log checkpoint, relog the intent item to keep + * the log tail moving forward. We're ok with this being racy + * because an incorrect decision means we'll be a little slower + * at pushing the tail. + */ + if (dfp->dfp_intent == NULL || + xfs_log_item_in_current_chkpt(dfp->dfp_intent)) + continue; + + /* + * Figure out where we need the tail to be in order to maintain + * the minimum required free space in the log. Only sample + * the log threshold once per call. + */ + if (threshold_lsn == NULLCOMMITLSN) { + threshold_lsn = xlog_grant_push_threshold(log, 0); + if (threshold_lsn == NULLCOMMITLSN) + break; + } + if (XFS_LSN_CMP(dfp->dfp_intent->li_lsn, threshold_lsn) >= 0) + continue; + + trace_xfs_defer_relog_intent((*tpp)->t_mountp, dfp); + XFS_STATS_INC((*tpp)->t_mountp, defer_relog); + dfp->dfp_intent = xfs_trans_item_relog(dfp->dfp_intent, *tpp); + } + + if ((*tpp)->t_flags & XFS_TRANS_DIRTY) + return xfs_defer_trans_roll(tpp); + return 0; +} + +/* + * Log an intent-done item for the first pending intent, and finish the work + * items. + */ +static int +xfs_defer_finish_one( + struct xfs_trans *tp, + struct xfs_defer_pending *dfp) +{ + const struct xfs_defer_op_type *ops = defer_op_types[dfp->dfp_type]; + void *state = NULL; + struct list_head *li, *n; + int error; + + trace_xfs_defer_pending_finish(tp->t_mountp, dfp); + + dfp->dfp_done = ops->create_done(tp, dfp->dfp_intent, dfp->dfp_count); + list_for_each_safe(li, n, &dfp->dfp_work) { + list_del(li); + dfp->dfp_count--; + error = ops->finish_item(tp, li, dfp->dfp_done, &state); + if (error == -EAGAIN) { + /* + * Caller wants a fresh transaction; put the work item + * back on the list and log a new log intent item to + * replace the old one. See "Requesting a Fresh + * Transaction while Finishing Deferred Work" above. + */ + list_add(li, &dfp->dfp_work); + dfp->dfp_count++; + dfp->dfp_done = NULL; + dfp->dfp_intent = NULL; + xfs_defer_create_intent(tp, dfp, false); + } + + if (error) + goto out; + } + + /* Done with the dfp, free it. */ + list_del(&dfp->dfp_list); + kmem_free(dfp); +out: + if (ops->finish_cleanup) + ops->finish_cleanup(tp, state, error); + return error; +} + +/* * Finish all the pending work. This involves logging intent items for * any work items that wandered in since the last transaction roll (if * one has even happened), rolling the transaction, and finishing the @@ -358,11 +475,7 @@ xfs_defer_finish_noroll( struct xfs_trans **tp) { struct xfs_defer_pending *dfp; - struct list_head *li; - struct list_head *n; - void *state; int error = 0; - const struct xfs_defer_op_type *ops; LIST_HEAD(dop_pending); ASSERT((*tp)->t_flags & XFS_TRANS_PERM_LOG_RES); @@ -371,87 +484,44 @@ xfs_defer_finish_noroll( /* Until we run out of pending work to finish... */ while (!list_empty(&dop_pending) || !list_empty(&(*tp)->t_dfops)) { - /* log intents and pull in intake items */ - xfs_defer_create_intents(*tp); - list_splice_tail_init(&(*tp)->t_dfops, &dop_pending); - /* - * Roll the transaction. + * Deferred items that are created in the process of finishing + * other deferred work items should be queued at the head of + * the pending list, which puts them ahead of the deferred work + * that was created by the caller. This keeps the number of + * pending work items to a minimum, which decreases the amount + * of time that any one intent item can stick around in memory, + * pinning the log tail. */ + xfs_defer_create_intents(*tp); + list_splice_init(&(*tp)->t_dfops, &dop_pending); + error = xfs_defer_trans_roll(tp); if (error) - goto out; + goto out_shutdown; + + /* Possibly relog intent items to keep the log moving. */ + error = xfs_defer_relog(tp, &dop_pending); + if (error) + goto out_shutdown; - /* Log an intent-done item for the first pending item. */ dfp = list_first_entry(&dop_pending, struct xfs_defer_pending, dfp_list); - ops = defer_op_types[dfp->dfp_type]; - trace_xfs_defer_pending_finish((*tp)->t_mountp, dfp); - dfp->dfp_done = ops->create_done(*tp, dfp->dfp_intent, - dfp->dfp_count); - - /* Finish the work items. */ - state = NULL; - list_for_each_safe(li, n, &dfp->dfp_work) { - list_del(li); - dfp->dfp_count--; - error = ops->finish_item(*tp, li, dfp->dfp_done, - &state); - if (error == -EAGAIN) { - /* - * Caller wants a fresh transaction; - * put the work item back on the list - * and jump out. - */ - list_add(li, &dfp->dfp_work); - dfp->dfp_count++; - break; - } else if (error) { - /* - * Clean up after ourselves and jump out. - * xfs_defer_cancel will take care of freeing - * all these lists and stuff. - */ - if (ops->finish_cleanup) - ops->finish_cleanup(*tp, state, error); - goto out; - } - } - if (error == -EAGAIN) { - /* - * Caller wants a fresh transaction, so log a - * new log intent item to replace the old one - * and roll the transaction. See "Requesting - * a Fresh Transaction while Finishing - * Deferred Work" above. - */ - dfp->dfp_intent = ops->create_intent(*tp, - dfp->dfp_count); - dfp->dfp_done = NULL; - list_for_each(li, &dfp->dfp_work) - ops->log_item(*tp, dfp->dfp_intent, li); - } else { - /* Done with the dfp, free it. */ - list_del(&dfp->dfp_list); - kmem_free(dfp); - } - - if (ops->finish_cleanup) - ops->finish_cleanup(*tp, state, error); - } - -out: - if (error) { - xfs_defer_trans_abort(*tp, &dop_pending); - xfs_force_shutdown((*tp)->t_mountp, SHUTDOWN_CORRUPT_INCORE); - trace_xfs_defer_finish_error(*tp, error); - xfs_defer_cancel_list((*tp)->t_mountp, &dop_pending); - xfs_defer_cancel(*tp); - return error; + error = xfs_defer_finish_one(*tp, dfp); + if (error && error != -EAGAIN) + goto out_shutdown; } trace_xfs_defer_finish_done(*tp, _RET_IP_); return 0; + +out_shutdown: + xfs_defer_trans_abort(*tp, &dop_pending); + xfs_force_shutdown((*tp)->t_mountp, SHUTDOWN_CORRUPT_INCORE); + trace_xfs_defer_finish_error(*tp, error); + xfs_defer_cancel_list((*tp)->t_mountp, &dop_pending); + xfs_defer_cancel(*tp); + return error; } int @@ -552,3 +622,137 @@ xfs_defer_move( xfs_defer_reset(stp); } + +/* + * Prepare a chain of fresh deferred ops work items to be completed later. Log + * recovery requires the ability to put off until later the actual finishing + * work so that it can process unfinished items recovered from the log in + * correct order. + * + * Create and log intent items for all the work that we're capturing so that we + * can be assured that the items will get replayed if the system goes down + * before log recovery gets a chance to finish the work it put off. The entire + * deferred ops state is transferred to the capture structure and the + * transaction is then ready for the caller to commit it. If there are no + * intent items to capture, this function returns NULL. + * + * If capture_ip is not NULL, the capture structure will obtain an extra + * reference to the inode. + */ +static struct xfs_defer_capture * +xfs_defer_ops_capture( + struct xfs_trans *tp, + struct xfs_inode *capture_ip) +{ + struct xfs_defer_capture *dfc; + + if (list_empty(&tp->t_dfops)) + return NULL; + + /* Create an object to capture the defer ops. */ + dfc = kmem_zalloc(sizeof(*dfc), KM_NOFS); + INIT_LIST_HEAD(&dfc->dfc_list); + INIT_LIST_HEAD(&dfc->dfc_dfops); + + xfs_defer_create_intents(tp); + + /* Move the dfops chain and transaction state to the capture struct. */ + list_splice_init(&tp->t_dfops, &dfc->dfc_dfops); + dfc->dfc_tpflags = tp->t_flags & XFS_TRANS_LOWMODE; + tp->t_flags &= ~XFS_TRANS_LOWMODE; + + /* Capture the remaining block reservations along with the dfops. */ + dfc->dfc_blkres = tp->t_blk_res - tp->t_blk_res_used; + dfc->dfc_rtxres = tp->t_rtx_res - tp->t_rtx_res_used; + + /* Preserve the log reservation size. */ + dfc->dfc_logres = tp->t_log_res; + + /* + * Grab an extra reference to this inode and attach it to the capture + * structure. + */ + if (capture_ip) { + ihold(VFS_I(capture_ip)); + dfc->dfc_capture_ip = capture_ip; + } + + return dfc; +} + +/* Release all resources that we used to capture deferred ops. */ +void +xfs_defer_ops_release( + struct xfs_mount *mp, + struct xfs_defer_capture *dfc) +{ + xfs_defer_cancel_list(mp, &dfc->dfc_dfops); + if (dfc->dfc_capture_ip) + xfs_irele(dfc->dfc_capture_ip); + kmem_free(dfc); +} + +/* + * Capture any deferred ops and commit the transaction. This is the last step + * needed to finish a log intent item that we recovered from the log. If any + * of the deferred ops operate on an inode, the caller must pass in that inode + * so that the reference can be transferred to the capture structure. The + * caller must hold ILOCK_EXCL on the inode, and must unlock it before calling + * xfs_defer_ops_continue. + */ +int +xfs_defer_ops_capture_and_commit( + struct xfs_trans *tp, + struct xfs_inode *capture_ip, + struct list_head *capture_list) +{ + struct xfs_mount *mp = tp->t_mountp; + struct xfs_defer_capture *dfc; + int error; + + ASSERT(!capture_ip || xfs_isilocked(capture_ip, XFS_ILOCK_EXCL)); + + /* If we don't capture anything, commit transaction and exit. */ + dfc = xfs_defer_ops_capture(tp, capture_ip); + if (!dfc) + return xfs_trans_commit(tp); + + /* Commit the transaction and add the capture structure to the list. */ + error = xfs_trans_commit(tp); + if (error) { + xfs_defer_ops_release(mp, dfc); + return error; + } + + list_add_tail(&dfc->dfc_list, capture_list); + return 0; +} + +/* + * Attach a chain of captured deferred ops to a new transaction and free the + * capture structure. If an inode was captured, it will be passed back to the + * caller with ILOCK_EXCL held and joined to the transaction with lockflags==0. + * The caller now owns the inode reference. + */ +void +xfs_defer_ops_continue( + struct xfs_defer_capture *dfc, + struct xfs_trans *tp, + struct xfs_inode **captured_ipp) +{ + ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES); + ASSERT(!(tp->t_flags & XFS_TRANS_DIRTY)); + + /* Lock and join the captured inode to the new transaction. */ + if (dfc->dfc_capture_ip) { + xfs_ilock(dfc->dfc_capture_ip, XFS_ILOCK_EXCL); + xfs_trans_ijoin(tp, dfc->dfc_capture_ip, 0); + } + *captured_ipp = dfc->dfc_capture_ip; + + /* Move captured dfops chain and state to the transaction. */ + list_splice_init(&dfc->dfc_dfops, &tp->t_dfops); + tp->t_flags |= dfc->dfc_tpflags; + + kmem_free(dfc); +} |