linux-stable/fs/xfs
Dave Chinner 77d7a0c2ee xfs: Non-blocking inode locking in IO completion
The introduction of barriers to loop devices has created a new IO
order completion dependency that XFS does not handle. The loop
device implements barriers using fsync and so turns a log IO in the
XFS filesystem on the loop device into a data IO in the backing
filesystem. That is, the completion of log IOs in the loop
filesystem are now dependent on completion of data IO in the backing
filesystem.

This can cause deadlocks when a flush daemon issues a log force with
an inode locked because the IO completion of IO on the inode is
blocked by the inode lock. This in turn prevents further data IO
completion from occuring on all XFS filesystems on that CPU (due to
the shared nature of the completion queues). This then prevents the
log IO from completing because the log is waiting for data IO
completion as well.

The fix for this new completion order dependency issue is to make
the IO completion inode locking non-blocking. If the inode lock
can't be grabbed, simply requeue the IO completion back to the work
queue so that it can be processed later. This prevents the
completion queue from being blocked and allows data IO completion on
other inodes to proceed, hence avoiding completion order dependent
deadlocks.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:34:52 -06:00
..
linux-2.6 xfs: Non-blocking inode locking in IO completion 2010-03-01 16:34:52 -06:00
quota fs/xfs: Correct NULL test 2010-02-13 13:22:53 -06:00
support xfs: event tracing support 2009-12-14 23:08:16 -06:00
Kconfig xfs: use generic Posix ACL code 2009-06-10 17:07:47 +02:00
Makefile xfs: merge xfs_lrw.c into xfs_file.c 2010-03-01 16:34:18 -06:00
xfs.h xfs: event tracing support 2009-12-14 23:08:16 -06:00
xfs_acl.h xfs: convert attr to use unsigned names 2010-01-20 10:47:48 +11:00
xfs_ag.h xfs: embed the pagb_list array in the perag structure 2010-01-15 15:34:39 -06:00
xfs_alloc.c xfs: cleanup up xfs_log_force calling conventions 2010-01-21 13:44:49 -06:00
xfs_alloc.h xfs: event tracing support 2009-12-14 23:08:16 -06:00
xfs_alloc_btree.c xfs: Don't directly reference m_perag in allocation code 2010-01-15 15:33:12 -06:00
xfs_alloc_btree.h
xfs_arch.h xfs: use generic Posix ACL code 2009-06-10 17:07:47 +02:00
xfs_attr.c xfs: remove duplicate buffer flags 2010-01-21 13:44:36 -06:00
xfs_attr.h xfs: convert attr to use unsigned names 2010-01-20 10:47:48 +11:00
xfs_attr_leaf.c xfs: remove duplicate buffer flags 2010-01-21 13:44:36 -06:00
xfs_attr_leaf.h
xfs_attr_sf.h xfs: convert attr to use unsigned names 2010-01-20 10:47:48 +11:00
xfs_bit.c
xfs_bit.h
xfs_bmap.c xfs: suppress spurious uninitialised var warning in xfs_bmapi() 2010-01-20 10:50:06 +11:00
xfs_bmap.h xfs: event tracing support 2009-12-14 23:08:16 -06:00
xfs_bmap_btree.c xfs: make several more functions static 2010-01-15 15:31:38 -06:00
xfs_bmap_btree.h xfs: make several more functions static 2010-01-15 15:31:38 -06:00
xfs_btree.c xfs: remove duplicate buffer flags 2010-01-21 13:44:36 -06:00
xfs_btree.h xfs: add more statics & drop some unused functions 2009-08-31 14:46:20 -05:00
xfs_btree_trace.c
xfs_btree_trace.h xfs: event tracing support 2009-12-14 23:08:16 -06:00
xfs_buf_item.c xfs: Don't issue buffer IO direct from AIL push V2 2010-02-02 10:13:42 +11:00
xfs_buf_item.h xfs: event tracing support 2009-12-14 23:08:16 -06:00
xfs_da_btree.c xfs: convert dirnameops to unsigned char names 2010-01-20 10:47:17 +11:00
xfs_da_btree.h xfs: convert dirnameops to unsigned char names 2010-01-20 10:47:17 +11:00
xfs_dfrag.c xfs: clean up inconsistent variable naming in xfs_swap_extent 2010-01-15 15:31:23 -06:00
xfs_dfrag.h xfs: clean up inconsistent variable naming in xfs_swap_extent 2010-01-15 15:31:23 -06:00
xfs_dinode.h
xfs_dir2.c xfs: clean up sign warnings in dir2 code 2010-01-20 10:48:05 +11:00
xfs_dir2.h xfs: make xfs_dir_cilookup_result use unsigned char 2010-01-20 10:47:25 +11:00
xfs_dir2_block.c xfs: clean up sign warnings in dir2 code 2010-01-20 10:48:05 +11:00
xfs_dir2_block.h
xfs_dir2_data.c
xfs_dir2_data.h
xfs_dir2_leaf.c xfs: clean up sign warnings in dir2 code 2010-01-20 10:48:05 +11:00
xfs_dir2_leaf.h
xfs_dir2_node.c xfs: make several more functions static 2010-01-15 15:31:38 -06:00
xfs_dir2_node.h xfs: make several more functions static 2010-01-15 15:31:38 -06:00
xfs_dir2_sf.c xfs: clean up sign warnings in dir2 code 2010-01-20 10:48:05 +11:00
xfs_dir2_sf.h
xfs_dmapi.h
xfs_dmops.c
xfs_error.c
xfs_error.h
xfs_extfree_item.c xfs: kill XLOG_VEC_SET_TYPE 2010-01-21 13:44:43 -06:00
xfs_extfree_item.h
xfs_filestream.c xfs: Kill filestreams cache flush 2010-01-15 15:34:22 -06:00
xfs_filestream.h xfs: Kill filestreams cache flush 2010-01-15 15:34:22 -06:00
xfs_fs.h trivial: fix typo "for for" in multiple files 2009-09-21 15:14:54 +02:00
xfs_fsops.c xfs: Replace per-ag array with a radix tree 2010-01-15 15:33:52 -06:00
xfs_fsops.h
xfs_ialloc.c xfs: remove duplicate buffer flags 2010-01-21 13:44:36 -06:00
xfs_ialloc.h xfs: rationalize xfs_inobt_lookup* 2009-09-01 12:45:39 -05:00
xfs_ialloc_btree.c
xfs_ialloc_btree.h
xfs_iget.c xfs: rename xfs_get_perag 2010-01-15 15:33:02 -06:00
xfs_inode.c xfs: Use delayed write for inodes rather than async V2 2010-02-06 12:39:36 +11:00
xfs_inode.h xfs: implement optimized fdatasync 2010-03-01 16:34:45 -06:00
xfs_inode_item.c xfs: Don't issue buffer IO direct from AIL push V2 2010-02-02 10:13:42 +11:00
xfs_inode_item.h xfs: Don't issue buffer IO direct from AIL push V2 2010-02-02 10:13:42 +11:00
xfs_inum.h xfs: remove XFS_INO64_OFFSET 2009-08-31 14:46:22 -05:00
xfs_iomap.c xfs: event tracing support 2009-12-14 23:08:16 -06:00
xfs_iomap.h xfs: event tracing support 2009-12-14 23:08:16 -06:00
xfs_itable.c xfs: replace KM_LARGE with explicit vmalloc use 2010-01-21 13:44:56 -06:00
xfs_itable.h xfs: add more statics & drop some unused functions 2009-08-31 14:46:20 -05:00
xfs_log.c xfs: cleanup up xfs_log_force calling conventions 2010-01-21 13:44:49 -06:00
xfs_log.h xfs: cleanup up xfs_log_force calling conventions 2010-01-21 13:44:49 -06:00
xfs_log_priv.h xfs: make several more functions static 2010-01-15 15:31:38 -06:00
xfs_log_recover.c xfs: cleanup up xfs_log_force calling conventions 2010-01-21 13:44:49 -06:00
xfs_log_recover.h xfs: Use list_heads for log recovery item lists 2010-01-15 15:31:51 -06:00
xfs_mount.c xfs: merge xfs_lrw.c into xfs_file.c 2010-03-01 16:34:18 -06:00
xfs_mount.h xfs: more reserved blocks fixups 2010-02-08 17:41:48 -06:00
xfs_mru_cache.c xfs: Kill filestreams cache flush 2010-01-15 15:34:22 -06:00
xfs_mru_cache.h xfs: Kill filestreams cache flush 2010-01-15 15:34:22 -06:00
xfs_quota.h xfs: kill the unused XFS_QMOPT_* flush flags V2 2010-02-04 09:48:58 +11:00
xfs_refcache.h
xfs_rename.c xfs: event tracing support 2009-12-14 23:08:16 -06:00
xfs_rtalloc.c xfs: fix missing error check in xfs_rtfree_range 2010-01-15 13:46:19 -06:00
xfs_rtalloc.h
xfs_rw.c xfs: only clear the suid bit once in xfs_write 2010-02-12 13:43:57 -06:00
xfs_rw.h xfs: only clear the suid bit once in xfs_write 2010-02-12 13:43:57 -06:00
xfs_sb.h
xfs_trans.c xfs: cleanup up xfs_log_force calling conventions 2010-01-21 13:44:49 -06:00
xfs_trans.h xfs: Don't issue buffer IO direct from AIL push V2 2010-02-02 10:13:42 +11:00
xfs_trans_ail.c xfs: Don't issue buffer IO direct from AIL push V2 2010-02-02 10:13:42 +11:00
xfs_trans_buf.c xfs: remove duplicate buffer flags 2010-01-21 13:44:36 -06:00
xfs_trans_extfree.c
xfs_trans_inode.c xfs: simplify xfs_trans_iget 2009-09-01 12:46:16 -05:00
xfs_trans_item.c
xfs_trans_priv.h
xfs_trans_space.h
xfs_types.h xfs: directory names are unsigned 2010-01-20 10:44:58 +11:00
xfs_utils.c xfs: kill xfs_qmops 2009-06-08 15:33:32 +02:00
xfs_utils.h
xfs_vnodeops.c xfs: remove wrapper for the fsync file operation 2010-03-01 16:34:38 -06:00
xfs_vnodeops.h xfs: remove wrapper for the fsync file operation 2010-03-01 16:34:38 -06:00