block: fix no diskstat problem

The commit below in 2.6-block/for-2.6.31 causes no diskstat problem
because the blk_discard_rq() check was added with '&&'.
It should be 'blk_fs_request() || blk_discard_rq()'.
This patch does it and fixes the no diskstat problem.
Please review and apply.

------ /proc/diskstat without this patch -------------------------------------
   8       0 sda 0 0 0 0 0 0 0 0 0 0 0
------------------------------------------------------------------------------

----- /proc/diskstat with this patch applied ---------------------------------
   8       0 sda 4186 303 373621 61600 9578 3859 107468 169479 2 89755 231059
------------------------------------------------------------------------------

--------------------------------------------------------------------------
commit c69d48540c
Author: Jens Axboe <jens.axboe@oracle.com>
Date:   Fri Apr 24 08:12:19 2009 +0200

    block: include discard requests in IO accounting

    We currently don't do merging on discard requests, but we potentially
    could. If we do, then we need to include discard requests in the IO
    accounting, or merging would end up decrementing in_flight IO counters
    for an IO which never incremented them.

    So enable accounting for discard requests.

<snip>

 static inline int blk_do_io_stat(struct request *rq)
 {
-       return rq->rq_disk && blk_rq_io_stat(rq) && blk_fs_request(rq);
+       return rq->rq_disk && blk_rq_io_stat(rq) && blk_fs_request(rq) &&
+               blk_discard_rq(rq);
 }
--------------------------------------------------------------------------

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
Kiyoshi Ueda 2009-05-27 14:50:02 +02:00 committed by Jens Axboe
parent ba396a6c10
commit 3c4198e874

View file

@ -156,12 +156,12 @@ static inline int blk_cpu_to_group(int cpu)
* *
* a) it's attached to a gendisk, and * a) it's attached to a gendisk, and
* b) the queue had IO stats enabled when this request was started, and * b) the queue had IO stats enabled when this request was started, and
* c) it's a file system request * c) it's a file system request or a discard request
*/ */
static inline int blk_do_io_stat(struct request *rq) static inline int blk_do_io_stat(struct request *rq)
{ {
return rq->rq_disk && blk_rq_io_stat(rq) && blk_fs_request(rq) && return rq->rq_disk && blk_rq_io_stat(rq) &&
blk_discard_rq(rq); (blk_fs_request(rq) || blk_discard_rq(rq));
} }
#endif #endif