diff options
| author | Jan Kara <jack@suse.cz> | 2013-11-05 16:55:45 +1100 |
|---|---|---|
| committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2013-11-05 16:55:45 +1100 |
| commit | 4aea99c29d04c73030952743329e26c5339da51e (patch) | |
| tree | 98544a95e7a3b739c2e4d71746ded4f01e7f7fb6 /fs | |
| parent | 596b741d29d0896b77c513d14c99602c331d69ae (diff) | |
writeback-do-not-sync-data-dirtied-after-sync-start-fix-2.txt
On Wed 09-10-13 14:21:25, Andrew Morton wrote:
> On Wed, 9 Oct 2013 17:03:25 +0200 Jan Kara <jack@suse.cz> wrote:
>
> > From: Jan Kara <jack@suse.cz>
> > Date: Wed, 9 Oct 2013 15:41:50 +0200
> > Subject: [PATCH] writeback: Use older_than_this_is_set instead of magic
> > older_than_this == 0
> >
> > Currently we use 0 as a special value of work->older_than_this to
> > indicate that wb_writeback() should set work->older_that_this to current
> > time. This works but it is a bit magic. So use a special flag in
> > work_struct for that.
>
> OK.
>
> > - if (!work->older_than_this)
> > + if (!work->older_than_this_is_set)
> > work->older_than_this = jiffies;
>
> It would be logical although presumably unneeded to set
> older_than_this_is_set here?
Yes. Updated.
> > Also fixup writeback from workqueue rescuer to include all inodes.
>
> There's nothing in the patch which matches this sentence?
The sentence is about the hunk below. writeback_inodes_wb() is special in
that it directly calls queue_io() (everything else goes through
wb_writeback()) and my previous patch thus resulted in using 0 as an
older_than_this value => likely we wouldn't queue any inodes for writeback.
I've added WARN_ON_ONCE into move_expired_inodes() to increase a chance of
catching such mistakes in future (although in this particular case it
wouldn't really help because writeback_inodes_wb() gets hardly ever
called).
Currently we use 0 as a special value of work->older_than_this to
indicate that wb_writeback() should set work->older_that_this to current
time. This works but it is a bit magic. So use a special flag in
work_struct for that.
Also fixup writeback from workqueue rescuer (writeback_inodes_wb()) to
include all inodes. Currently it would use 0 as an older_than_this value
thus queue_io() would likely not queue any inodes for writeback.
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/fs-writeback.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 65e66caec76f..ba332d2c596a 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -251,6 +251,7 @@ static int move_expired_inodes(struct list_head *delaying_queue, int do_sb_sort = 0; int moved = 0; + WARN_ON_ONCE(!work->older_than_this_is_set); while (!list_empty(delaying_queue)) { inode = wb_inode(delaying_queue->prev); if (inode_dirtied_after(inode, work->older_than_this)) @@ -800,8 +801,10 @@ static long wb_writeback(struct bdi_writeback *wb, struct inode *inode; long progress; - if (!work->older_than_this_is_set) + if (!work->older_than_this_is_set) { work->older_than_this = jiffies; + work->older_than_this_is_set = 1; + } spin_lock(&wb->list_lock); for (;;) { |