Dave Chinner 7ac956576d xfs: fix race condition in AIL push trigger ... The recent conversion of the xfsaild functionality to a work queue introduced a hard-to-hit log space grant hang. One is caused by a race condition in determining whether there is a psh in progress or not. The XFS_AIL_PUSHING_BIT is used to determine whether a push is currently in progress. When the AIL push work completes, it checked whether the target changed and cleared the PUSHING bit to allow a new push to be requeued. The race condition is as follows: Thread 1 push work smp_wmb() smp_rmb() check ailp->xa_target unchanged update ailp->xa_target test/set PUSHING bit does not queue clear PUSHING bit does not requeue Now that the push target is updated, new attempts to push the AIL will not trigger as the push target will be the same, and hence despite trying to push the AIL we won't ever wake it again. The fix is to ensure that the AIL push work clears the PUSHING bit before it checks if the target is unchanged. As a result, both push triggers operate on the same test/set bit criteria, so even if we race in the push work and miss the target update, the thread requesting the push will still set the PUSHING bit and queue the push work to occur. For safety sake, the same queue check is done if the push work detects the target change, though only one of the two will will queue new work due to the use of test_and_set_bit() checks. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com> (cherry picked from commit e4d3c4a43b)		2011-05-09 18:35:04 -05:00
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linux-2.6	xfs: ensure reclaim cursor is reset correctly at end of AG	2011-05-09 18:35:03 -05:00
quota	Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs	2011-04-11 15:48:57 -07:00
support	xfs: kill support/debug.[ch]	2011-03-07 10:09:35 +11:00
Kconfig	quota: Make QUOTACTL config be selected by its users	2010-10-05 12:16:37 +02:00
Makefile	Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs	2011-03-21 14:24:56 -07:00
xfs.h	…
xfs_acl.h	fs: provide rcu-walk aware permission i_ops	2011-01-07 17:50:29 +11:00
xfs_ag.h	xfs: convert pag_ici_lock to a spin lock	2010-12-16 17:08:41 +11:00
xfs_alloc.c	xfs: catch bad block numbers freeing extents.	2011-04-08 12:45:07 +10:00
xfs_alloc.h	xfs: limit extent length for allocation to AG size	2011-01-28 09:05:35 -06:00
xfs_alloc_btree.c	xfs: remove the ->kill_root btree operation	2010-10-18 15:07:38 -05:00
xfs_alloc_btree.h	…
xfs_arch.h	…
xfs_attr.c	xfs: remove xfs_buf wrappers	2010-10-18 15:08:07 -05:00
xfs_attr.h	…
xfs_attr_leaf.c	xfs: use KM_NOFS for allocations during attribute list operations	2010-12-23 11:57:37 +11:00
xfs_attr_leaf.h	…
xfs_attr_sf.h	…
xfs_bit.c	…
xfs_bit.h	…
xfs_bmap.c	xfs: Convert remaining cmn_err() callers to new API	2011-03-07 10:08:35 +11:00
xfs_bmap.h	xfs: fix failed write truncation handling.	2010-12-01 07:40:19 -06:00
xfs_bmap_btree.c	…
xfs_bmap_btree.h	…
xfs_btree.c	xfs: connect up buffer reclaim priority hooks	2010-12-02 16:31:13 +11:00
xfs_btree.h	xfs: remove the ->kill_root btree operation	2010-10-18 15:07:38 -05:00
xfs_btree_trace.c	…
xfs_btree_trace.h	…
xfs_buf_item.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
xfs_buf_item.h	xfs: use struct list_head for the buf cancel table	2010-12-16 16:05:22 -06:00
xfs_da_btree.c	xfs: Convert remaining cmn_err() callers to new API	2011-03-07 10:08:35 +11:00
xfs_da_btree.h	…
xfs_dfrag.c	xfs: convert xfs_fs_cmn_err to new error logging API	2011-03-07 10:05:35 +11:00
xfs_dfrag.h	…
xfs_dinode.h	xfs: Extend project quotas to support 32bit project ids	2010-10-18 15:08:08 -05:00
xfs_dir2.c	xfs: convert xfs_fs_cmn_err to new error logging API	2011-03-07 10:05:35 +11:00
xfs_dir2.h	…
xfs_dir2_block.c	xfs: fix gcc 4.6 set but not read and unused statement warnings	2010-07-26 13:16:51 -05:00
xfs_dir2_block.h	…
xfs_dir2_data.c	…
xfs_dir2_data.h	…
xfs_dir2_leaf.c	xfs: remove xfs_buf wrappers	2010-10-18 15:08:07 -05:00
xfs_dir2_leaf.h	…
xfs_dir2_node.c	xfs: Convert remaining cmn_err() callers to new API	2011-03-07 10:08:35 +11:00
xfs_dir2_node.h	…
xfs_dir2_sf.c	…
xfs_dir2_sf.h	…
xfs_error.c	xfs: Convert remaining cmn_err() callers to new API	2011-03-07 10:08:35 +11:00
xfs_error.h	xfs: kill support/debug.[ch]	2011-03-07 10:09:35 +11:00
xfs_extfree_item.c	xfs: fix efi item leak on forced shutdown	2011-01-28 09:01:33 -06:00
xfs_extfree_item.h	xfs: Pull EFI/EFD handling out from under the AIL lock	2010-12-20 11:59:49 +11:00
xfs_filestream.c	xfs: tell lockdep about parent iolock usage in filestreams	2010-11-10 12:00:48 -06:00
xfs_filestream.h	xfs: clean up filestreams helpers	2010-07-26 13:16:51 -05:00
xfs_fs.h	xfs: Extend project quotas to support 32bit project ids	2010-10-18 15:08:08 -05:00
xfs_fsops.c	xfs: convert xfs_fs_cmn_err to new error logging API	2011-03-07 10:05:35 +11:00
xfs_fsops.h	xfs: ensure log covering transactions are synchronous	2011-01-11 20:28:17 -06:00
xfs_ialloc.c	xfs: Convert remaining cmn_err() callers to new API	2011-03-07 10:08:35 +11:00
xfs_ialloc.h	…
xfs_ialloc_btree.c	xfs: remove the ->kill_root btree operation	2010-10-18 15:07:38 -05:00
xfs_ialloc_btree.h	…
xfs_iget.c	Merge branch 'master' into for-linus-merged	2011-01-10 21:35:55 -06:00
xfs_inode.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
xfs_inode.h	Fix common misspellings	2011-03-31 11:26:23 -03:00
xfs_inode_item.c	xfs: fix extent format buffer allocation size	2011-04-08 12:45:07 +10:00
xfs_inode_item.h	…
xfs_inum.h	…
xfs_iomap.c	xfs: rename xfs_cmn_err_fsblock_zero()	2011-03-07 10:06:35 +11:00
xfs_iomap.h	xfs: kill xfs_iomap	2010-12-16 16:05:51 -06:00
xfs_itable.c	xfs: fix variable set but not used warnings	2011-04-08 08:09:12 -05:00
xfs_itable.h	…
xfs_log.c	xfs: convert log tail checking to a warning	2011-04-08 12:45:07 +10:00
xfs_log.h	xfs: handle CIl transaction commit failures correctly	2011-01-28 09:05:36 -06:00
xfs_log_cil.c	xfs: handle CIl transaction commit failures correctly	2011-01-28 09:05:36 -06:00
xfs_log_priv.h	Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs	2011-04-11 15:48:57 -07:00
xfs_log_recover.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
xfs_log_recover.h	…
xfs_mount.c	xfs: Convert remaining cmn_err() callers to new API	2011-03-07 10:08:35 +11:00
xfs_mount.h	xfs: introduce background inode reclaim work	2011-04-08 12:45:07 +10:00
xfs_mru_cache.c	xfs: convert to alloc_workqueue()	2011-02-01 11:42:43 +01:00
xfs_mru_cache.h	…
xfs_quota.h	xfs: Convert xlog_warn to new logging interface	2011-03-07 10:01:35 +11:00
xfs_rename.c	xfs: log timestamp changes to the source inode in rename	2010-12-09 17:07:02 -06:00
xfs_rtalloc.c	xfs: Convert remaining cmn_err() callers to new API	2011-03-07 10:08:35 +11:00
xfs_rtalloc.h	xfs: Convert remaining cmn_err() callers to new API	2011-03-07 10:08:35 +11:00
xfs_rw.c	xfs: Convert remaining cmn_err() callers to new API	2011-03-07 10:08:35 +11:00
xfs_rw.h	…
xfs_sb.h	xfs: Extend project quotas to support 32bit project ids	2010-10-18 15:08:08 -05:00
xfs_trans.c	xfs: handle CIl transaction commit failures correctly	2011-01-28 09:05:36 -06:00
xfs_trans.h	xfs: more sensible inode refcounting for ialloc	2011-02-22 20:32:28 -06:00
xfs_trans_ail.c	xfs: fix race condition in AIL push trigger	2011-05-09 18:35:04 -05:00
xfs_trans_buf.c	xfs: xfs_trans_read_buf() should return an error on failure	2011-03-26 09:14:44 +11:00
xfs_trans_extfree.c	xfs: Pull EFI/EFD handling out from under the AIL lock	2010-12-20 11:59:49 +11:00
xfs_trans_inode.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
xfs_trans_priv.h	xfs: push the AIL from memory reclaim and periodic sync	2011-04-08 12:45:07 +10:00
xfs_trans_space.h	…
xfs_types.h	xfs: Extend project quotas to support 32bit project ids	2010-10-18 15:08:08 -05:00
xfs_utils.c	xfs: remove xfs_cred.h	2010-10-18 15:08:06 -05:00
xfs_utils.h	xfs: remove xfs_cred.h	2010-10-18 15:08:06 -05:00
xfs_vnodeops.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
xfs_vnodeops.h	xfs: preallocation transactions do not need to be synchronous	2011-03-26 09:13:08 +11:00