Revert "cfq: Remove special treatment for metadata rqs."
authorJens Axboe <jaxboe@fusionio.com>
Fri, 19 Aug 2011 06:34:48 +0000 (08:34 +0200)
committerJens Axboe <jaxboe@fusionio.com>
Fri, 19 Aug 2011 06:34:48 +0000 (08:34 +0200)
commitb53d1ed734a2b9af8da115b836b658daa7d47a48
tree07ed12caa6fd50f97568f419448cf03906d980c4
parent4853abaae7e4a2af938115ce9071ef8684fb7af4
Revert "cfq: Remove special treatment for metadata rqs."

We have a kernel build regression since 3.1-rc1, which is about 10%
regression. The kernel source is in an ext3 filesystem.
Alex Shi bisect it to commit:
commit a07405b7802691d29ab3b23bdc76ee6d006aad0b
Author: Justin TerAvest <teravest@google.com>
Date:   Sun Jul 10 22:09:19 2011 +0200

    cfq: Remove special treatment for metadata rqs.

Apparently this is caused by lack metadata preemption, where ext3/ext4
do use READ_META. I didn't see a way to fix the issue, so suggest
reverting the patch.

This reverts commit a07405b7802691d29ab3b23bdc76ee6d006aad0b.

Reported-by: Alex Shi<alex.shi@intel.com>
Reported-by: Shaohua Li<shaohua.li@intel.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
block/cfq-iosched.c