writeback: integrated background writeback work
authorJan Kara <jack@suse.cz>
Thu, 13 Jan 2011 23:45:44 +0000 (15:45 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 14 Jan 2011 01:32:32 +0000 (17:32 -0800)
commit6585027a5e8cb490e3a761b2f3f3c3acf722aff2
treeac856c00c148d590d6b7632cc11bc23be6a9ccc2
parentb44129b30652c8771db2265939bb8b463724043d
writeback: integrated background writeback work

Check whether background writeback is needed after finishing each work.

When bdi flusher thread finishes doing some work check whether any kind of
background writeback needs to be done (either because
dirty_background_ratio is exceeded or because we need to start flushing
old inodes).  If so, just do background write back.

This way, bdi_start_background_writeback() just needs to wake up the
flusher thread.  It will do background writeback as soon as there is no
other work.

This is a preparatory patch for the next patch which stops background
writeback as soon as there is other work to do.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Engelhardt <jengelh@medozas.de>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/fs-writeback.c