Re: [PATCH] ext4: fix blkdev_issue_flush() failure handling

Theodore Tso
2009-03-30T02:25:39Z

On Sun, Mar 29, 2009 at 12:43:22PM -0500, Eric Sandeen wrote:
>
> As long as we keep the call there this is probably good, but after
> talking w/ Chris Mason, I think the call is extraneous anyway and should
> probably just be removed...
>

Yes, I agree, but it takes a lot of digging to be completely sure of
that it's safe to remove it. Interestingly, it was you who added the
patch which added the call to blkdev_issue_flush():

commit d755fb384250d6bd7fd18a0930e71965acc8e72e
Author: Eric Sandeen <sandeen@redhat.com>
Date: Fri Jul 11 19:27:31 2008 -0400

ext4: call blkdev_issue_flush on fsync

To ensure that bits are truly on-disk after an fsync,
we should call blkdev_issue_flush if barriers are supported.

Inspired by an old thread on barriers, by reiserfs & xfs
which do the same, and by a patch SuSE ships with their kernel

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

When we remove it we should add a comment noting why it's not
necessary.

- Ted