Re: [patch]ext4: add block plug for .writepages

[Shaohua Li <shaohua.li@intel.com>]

On Tue, 2011-10-11 at 18:40 +0800, Kyungmin Park wrote:
> On Tue, Oct 11, 2011 at 1:51 AM, Ted Ts'o <tytso@mit.edu> wrote:
> > On Wed, Sep 28, 2011 at 11:09:40AM +0800, Shaohua Li wrote:
> >> I searched a little bit, looks only ext4 need it. here is the patch.
> >>
> >>
> >> Add block plug for ext4 .writepages. Though ext4 .writepages
> >> already handles request merge very well, block plug is still
> >> helpful to reduce block lock contention.
> >>
> >> Signed-off-by: Shaohua Li <shaohua.li@intel.com>
> 
> Does it require to add blk_finish_plug(&plug) when error case?
oops, we need.

Subject: ext4: calling blk_finish_plug in error path

Forgot calling blk_finish_plug in error code path. Thanks Kyungmin Park pointed
it out.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
---
 fs/ext4/inode.c |    1 +
 1 file changed, 1 insertion(+)

Index: linux/fs/ext4/inode.c
===================================================================
--- linux.orig/fs/ext4/inode.c	2011-10-12 08:46:32.000000000 +0800
+++ linux/fs/ext4/inode.c	2011-10-12 08:48:10.000000000 +0800
@@ -2144,6 +2144,7 @@ retry:
 			ext4_msg(inode->i_sb, KERN_CRIT, "%s: jbd2_start: "
 			       "%ld pages, ino %lu; err %d", __func__,
 				wbc->nr_to_write, inode->i_ino, ret);
+			blk_finish_plug(&plug);
 			goto out_writepages;
 		}