Theodore Ts'o f783f091e4 jbd2: trace when lock_buffer in do_get_write_access takes a long time ... While investigating interactivity problems it was clear that processes sometimes stall for long periods of times if an attempt is made to lock a buffer which is undergoing writeback. It would stall in a trace looking something like [<ffffffff811a39de>] __lock_buffer+0x2e/0x30 [<ffffffff8123a60f>] do_get_write_access+0x43f/0x4b0 [<ffffffff8123a7cb>] jbd2_journal_get_write_access+0x2b/0x50 [<ffffffff81220f79>] __ext4_journal_get_write_access+0x39/0x80 [<ffffffff811f3198>] ext4_reserve_inode_write+0x78/0xa0 [<ffffffff811f3209>] ext4_mark_inode_dirty+0x49/0x220 [<ffffffff811f57d1>] ext4_dirty_inode+0x41/0x60 [<ffffffff8119ac3e>] __mark_inode_dirty+0x4e/0x2d0 [<ffffffff8118b9b9>] update_time+0x79/0xc0 [<ffffffff8118ba98>] file_update_time+0x98/0x100 [<ffffffff81110ffc>] __generic_file_aio_write+0x17c/0x3b0 [<ffffffff811112aa>] generic_file_aio_write+0x7a/0xf0 [<ffffffff811ea853>] ext4_file_write+0x83/0xd0 [<ffffffff81172b23>] do_sync_write+0xa3/0xe0 [<ffffffff811731ae>] vfs_write+0xae/0x180 [<ffffffff8117361d>] sys_write+0x4d/0x90 [<ffffffff8159d62d>] system_call_fastpath+0x1a/0x1f [<ffffffffffffffff>] 0xffffffffffffffff Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>		2013-04-21 16:47:54 -04:00
..
checkpoint.c	jbd2: remove bh_state lock from checkpointing code	2012-03-13 22:45:25 -04:00
commit.c	jbd2: fix race between jbd2_journal_remove_checkpoint and ->j_commit_callback	2013-04-03 22:06:52 -04:00
journal.c	ext4/jbd2: don't wait (forever) for stale tid caused by wraparound	2013-04-03 22:02:52 -04:00
Kconfig	jbd2: Grab a reference to the crc32c driver if necessary	2012-05-27 07:50:56 -04:00
Makefile
recovery.c	jbd2: check return value of blkdev_issue_flush()	2012-08-17 09:56:17 -04:00
revoke.c	jbd2: checksum revocation blocks	2012-05-27 08:08:24 -04:00
transaction.c	jbd2: trace when lock_buffer in do_get_write_access takes a long time	2013-04-21 16:47:54 -04:00