linux/fs/xfs
Brian Foster 4703da7b78 xfs: close xc_cil list_empty() races with cil commit sequence
We have seen somewhat rare reports of the following assert from
xlog_cil_push_background() failing during ltp tests or somewhat
innocuous desktop root fs workloads (e.g., virt operations, initramfs
construction):

    ASSERT(!list_empty(&cil->xc_cil));

The reasoning behind the assert is that the transaction has inserted
items to the CIL and hit background push codepath all with
cil->xc_ctx_lock held for reading. This locks out background commit from
emptying the CIL, which acquires the lock for writing. Therefore, the
reasoning is that the items previously inserted in the CIL should still
be present.

The cil->xc_ctx_lock read lock is not sufficient to protect the xc_cil
list, however, due to how CIL insertion is handled.
xlog_cil_insert_items() inserts and reorders the dirty transaction items
to the tail of the CIL under xc_cil_lock. It uses list_move_tail() to
achieve insertion and reordering in the same block of code. This
function removes and reinserts an item to the tail of the list. If a
transaction commits an item that was already logged and thus already
resides in the CIL, and said item is the sole item on the list, the
removal and reinsertion creates a temporary state where the list is
actually empty.

This state is not valid and thus should never be observed by concurrent
transaction commit-side checks in the circumstances outlined above. We
do not want to acquire the xc_cil_lock in all of these instances as it
was previously removed and replaced with a separate push lock for
performance reasons. Therefore, close any races with list_empty() on the
insertion side by ensuring that the list is never in a transient empty
state.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-07-29 11:51:01 +10:00
..
libxfs xfs: xfs_bunmapi() does not need XFS_BMAPI_METADATA flag 2015-07-29 11:51:01 +10:00
Kconfig xfs: require 64-bit sector_t 2014-07-30 09:12:05 +10:00
kmem.c xfs: change kmem_free to use generic kvfree() 2015-02-02 09:54:18 +11:00
kmem.h xfs: change kmem_free to use generic kvfree() 2015-02-02 09:54:18 +11:00
Makefile xfs: implement pNFS export operations 2015-02-16 11:49:23 +11:00
mrlock.h
uuid.c
uuid.h
xfs_acl.c xfs: move most of xfs_sb.h to xfs_format.h 2014-11-28 14:27:09 +11:00
xfs_acl.h xfs: move acl structures to xfs_format.h 2014-11-28 14:24:37 +11:00
xfs_aops.c xfs: update for 4.2-rc1 2015-06-30 20:16:08 -07:00
xfs_aops.h xfs: add DAX file operations support 2015-06-04 09:18:53 +10:00
xfs_attr_inactive.c Merge branch 'xfs-misc-fixes-for-4.2-3' into for-next 2015-06-23 08:49:01 +10:00
xfs_attr_list.c xfs: pass attr geometry to attr leaf header conversion functions 2015-04-13 11:26:02 +10:00
xfs_attr.h
xfs_bit.c xfs: fix static and extern sparse warnings 2013-10-30 13:59:56 -05:00
xfs_bmap_util.c Merge branch 'xfs-commit-cleanup' into for-next 2015-06-04 13:55:48 +10:00
xfs_bmap_util.h xfs: Add support FALLOC_FL_INSERT_RANGE for fallocate 2015-03-25 15:08:56 +11:00
xfs_buf_item.c xfs: clarify async write failure ratelimit message 2015-02-24 10:14:04 +11:00
xfs_buf_item.h xfs: decouple inode and bmap btree header files 2013-10-23 16:28:49 -05:00
xfs_buf.c xfs: return a void pointer from xfs_buf_offset 2015-06-22 09:44:29 +10:00
xfs_buf.h xfs: return a void pointer from xfs_buf_offset 2015-06-22 09:44:29 +10:00
xfs_dir2_readdir.c Merge branch 'xfs-misc-fixes-for-3.19-2' into for-next 2014-12-04 09:46:17 +11:00
xfs_discard.c xfs: pass mp to XFS_WANT_CORRUPTED_GOTO 2015-02-23 22:39:08 +11:00
xfs_discard.h
xfs_dquot_item.c xfs: move most of xfs_sb.h to xfs_format.h 2014-11-28 14:27:09 +11:00
xfs_dquot_item.h xfs: remove the quotaoff log format from the quotaoff log item 2013-12-13 11:34:08 +11:00
xfs_dquot.c xfs: saner xfs_trans_commit interface 2015-06-04 13:48:08 +10:00
xfs_dquot.h xfs: fix implicit bool to int conversion 2015-01-09 10:48:58 +11:00
xfs_error.c xfs: remove inst_t 2015-06-22 09:44:02 +10:00
xfs_error.h xfs: remove inst_t 2015-06-22 09:44:02 +10:00
xfs_export.c VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
xfs_export.h
xfs_extent_busy.c xfs: merge xfs_ag.h into xfs_format.h 2014-11-28 14:25:04 +11:00
xfs_extent_busy.h xfs: decouple inode and bmap btree header files 2013-10-23 16:28:49 -05:00
xfs_extfree_item.c xfs: remove __psint_t and __psunsigned_t 2015-06-22 09:43:32 +10:00
xfs_extfree_item.h
xfs_file.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-07-04 19:36:06 -07:00
xfs_filestream.c xfs: clean up XFS_MIN_FREELIST macros 2015-06-22 10:13:30 +10:00
xfs_filestream.h xfs: add filestream allocator tracepoints 2014-04-23 07:11:52 +10:00
xfs_fsops.c Merge branch 'xfs-commit-cleanup' into for-next 2015-06-04 13:55:48 +10:00
xfs_fsops.h
xfs_globals.c xfs: export log_recovery_delay to delay mount time log recovery 2014-09-09 11:56:13 +10:00
xfs_icache.c xfs: inodes are new until the dentry cache is set up 2015-02-23 22:38:08 +11:00
xfs_icache.h xfs: merge xfs_ag.h into xfs_format.h 2014-11-28 14:25:04 +11:00
xfs_icreate_item.c xfs: move most of xfs_sb.h to xfs_format.h 2014-11-28 14:27:09 +11:00
xfs_icreate_item.h
xfs_inode_item.c xfs: move most of xfs_sb.h to xfs_format.h 2014-11-28 14:27:09 +11:00
xfs_inode_item.h xfs: remove the inode log format from the inode log item 2013-12-13 11:34:05 +11:00
xfs_inode.c Merge branch 'xfs-misc-fixes-for-4.2-3' into for-next 2015-06-23 08:49:01 +10:00
xfs_inode.h Merge branch 'xfs-mmap-lock' into for-next 2015-02-24 10:27:47 +11:00
xfs_ioctl32.c VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
xfs_ioctl32.h xfs: compat_xfs_bstat does not have forkoff 2014-10-02 09:17:58 +10:00
xfs_ioctl.c xfs: saner xfs_trans_commit interface 2015-06-04 13:48:08 +10:00
xfs_ioctl.h
xfs_iomap.c xfs: saner xfs_trans_commit interface 2015-06-04 13:48:08 +10:00
xfs_iomap.h xfs: pass a 64-bit count argument to xfs_iomap_write_unwritten 2015-01-09 10:48:12 +11:00
xfs_iops.c xfs: update for 4.2-rc1 2015-06-30 20:16:08 -07:00
xfs_iops.h xfs: inodes are new until the dentry cache is set up 2015-02-23 22:38:08 +11:00
xfs_itable.c xfs: use actual inode count for sparse records in bulkstat/inumbers 2015-05-29 09:04:19 +10:00
xfs_itable.h xfs: bulkstat chunk formatting cursor is broken 2014-11-07 08:30:30 +11:00
xfs_linux.h xfs: remove xfs_caddr_t 2015-06-22 09:45:10 +10:00
xfs_log_cil.c xfs: close xc_cil list_empty() races with cil commit sequence 2015-07-29 11:51:01 +10:00
xfs_log_priv.h xfs: use void pointers in log validation helpers 2015-06-22 09:44:47 +10:00
xfs_log_recover.c Merge branch 'xfs-misc-fixes-for-4.2-3' into for-next 2015-06-23 08:49:01 +10:00
xfs_log.c Merge branch 'xfs-misc-fixes-for-4.2-3' into for-next 2015-06-23 08:49:01 +10:00
xfs_log.h xfs: fix xfs_log_done interface 2015-06-04 13:48:20 +10:00
xfs_message.c xfs: move most of xfs_sb.h to xfs_format.h 2014-11-28 14:27:09 +11:00
xfs_message.h
xfs_mount.c Merge branch 'xfs-sparse-inode' into for-next 2015-06-01 10:51:38 +10:00
xfs_mount.h Merge branch 'xfs-dax-support' into for-next 2015-06-04 13:01:49 +10:00
xfs_mru_cache.c xfs: xfs_mru_cache_insert() should use GFP_NOFS 2015-03-25 14:57:53 +11:00
xfs_mru_cache.h xfs: embedd mru_elem into parent structure 2014-04-23 07:11:51 +10:00
xfs_pnfs.c xfs: saner xfs_trans_commit interface 2015-06-04 13:48:08 +10:00
xfs_pnfs.h xfs: unlock i_mutex in xfs_break_layouts 2015-04-13 11:38:29 +10:00
xfs_qm_bhv.c xfs: move most of xfs_sb.h to xfs_format.h 2014-11-28 14:27:09 +11:00
xfs_qm_syscalls.c xfs: saner xfs_trans_commit interface 2015-06-04 13:48:08 +10:00
xfs_qm.c xfs: saner xfs_trans_commit interface 2015-06-04 13:48:08 +10:00
xfs_qm.h xfs: Convert to using ->get_state callback 2015-03-04 16:06:36 +01:00
xfs_quota.h xfs: fix quota block reservation leak when tp allocates and frees blocks 2015-06-01 07:15:37 +10:00
xfs_quotaops.c xfs: Add support for Q_SETINFO 2015-03-04 16:06:38 +01:00
xfs_rtalloc.c xfs: saner xfs_trans_commit interface 2015-06-04 13:48:08 +10:00
xfs_rtalloc.h xfs: combine xfs_rtmodify_summary and xfs_rtget_summary 2014-09-09 11:58:42 +10:00
xfs_stats.c xfs: support the XFS_BTNUM_FINOBT free inode btree type 2014-04-24 16:00:52 +10:00
xfs_stats.h xfs: support the XFS_BTNUM_FINOBT free inode btree type 2014-04-24 16:00:52 +10:00
xfs_super.c xfs: add initial DAX support 2015-06-04 09:19:18 +10:00
xfs_super.h xfs: Remove icsb infrastructure 2015-02-23 21:22:31 +11:00
xfs_symlink.c xfs: xfs_bunmapi() does not need XFS_BMAPI_METADATA flag 2015-07-29 11:51:01 +10:00
xfs_symlink.h xfs: push down inactive transaction mgmt for remote symlinks 2013-10-08 14:53:02 -05:00
xfs_sysctl.c xfs: remove deprecated sysctls 2015-01-09 10:47:43 +11:00
xfs_sysctl.h xfs: export log_recovery_delay to delay mount time log recovery 2014-09-09 11:56:13 +10:00
xfs_sysfs.c xfs: export log_recovery_delay to delay mount time log recovery 2014-09-09 11:56:13 +10:00
xfs_sysfs.h xfs: add debug sysfs attribute set 2014-09-09 11:52:42 +10:00
xfs_trace.c xfs: move most of xfs_sb.h to xfs_format.h 2014-11-28 14:27:09 +11:00
xfs_trace.h xfs: allocate sparse inode chunks on full chunk allocation failure 2015-05-29 09:18:32 +10:00
xfs_trans_ail.c xfs: remove __psint_t and __psunsigned_t 2015-06-22 09:43:32 +10:00
xfs_trans_buf.c xfs: only trace buffer items if they exist 2015-02-10 09:23:40 +11:00
xfs_trans_dquot.c xfs: Clean up xfs_trans_dup_dqinfo 2015-06-01 10:50:00 +10:00
xfs_trans_extfree.c xfs: move most of xfs_sb.h to xfs_format.h 2014-11-28 14:27:09 +11:00
xfs_trans_inode.c xfs: move most of xfs_sb.h to xfs_format.h 2014-11-28 14:27:09 +11:00
xfs_trans_priv.h xfs: pass a boolean flag to xfs_trans_free_items 2015-06-04 13:47:43 +10:00
xfs_trans.c xfs: fix xfs_log_done interface 2015-06-04 13:48:20 +10:00
xfs_trans.h xfs: saner xfs_trans_commit interface 2015-06-04 13:48:08 +10:00
xfs_xattr.c VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
xfs.h