]> pilppa.com Git - linux-2.6-omap-h63xx.git/commit
writeback: fix time ordering of the per superblock dirty inode lists 5
authorAndrew Morton <akpm@linux-foundation.org>
Wed, 17 Oct 2007 06:30:36 +0000 (23:30 -0700)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Wed, 17 Oct 2007 15:43:02 +0000 (08:43 -0700)
commitc6945e77e477103057b4a639b4b01596f5257861
tree02e6b473143060cdec08f3d8447512d56ea699bd
parent1b43ef91d40190b16ba10218e66d5c2c4ba11de3
writeback: fix time ordering of the per superblock dirty inode lists 5

When the writeback function is operating in writeback-for-flushing mode (as
opposed to writeback-for-integrity) and it encounters an I_LOCKed inode, it
will skip writing that inode.  This is done for throughput and latency: move
on to another inode rather than blocking for this one.

Writeback skips this inode by moving it off s_io and onto s_dirty, so that
writeback can proceed with the other inodes on s_io.

However that inode movement can corrupt s_dirty's reverse-time-orderedness.
Fix that by using the new redirty_tail(), which will update the refiled
inode's dirtied_when field.

Note: the behaviour in here is a bit rude: if kupdate happens to come across a
locked inode then it will defer writeback of that inode for another 30
seconds.  We'll address that in the next patch.

Cc: Mike Waychison <mikew@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/fs-writeback.c