summaryrefslogtreecommitdiff
path: root/drivers/md
diff options
context:
space:
mode:
authorShaohua Li <shli@fb.com>2016-04-25 16:52:38 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-05-11 11:21:13 +0200
commitf3b51a03bea6dc4cda740481d48b2ff49abdced5 (patch)
tree189450adc4e7e63489209f9ae12ea56b119da19f /drivers/md
parent8d2923930be15a5b295ace2029c76653dc4def13 (diff)
MD: make bio mergeable
commit 9c573de3283af007ea11c17bde1e4568d9417328 upstream. blk_queue_split marks bio unmergeable, which makes sense for normal bio. But if dispatching the bio to underlayer disk, the blk_queue_split checks are invalid, hence it's possible the bio becomes mergeable. In the reported bug, this bug causes trim against raid0 performance slash https://bugzilla.kernel.org/show_bug.cgi?id=117051 Reported-and-tested-by: Park Ju Hyung <qkrwngud825@gmail.com> Fixes: 6ac45aeb6bca(block: avoid to merge splitted bio) Cc: Ming Lei <ming.lei@canonical.com> Cc: Neil Brown <neilb@suse.de> Reviewed-by: Jens Axboe <axboe@fb.com> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/md')
-rw-r--r--drivers/md/md.c2
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c
index b1e1f6b95782..c57fdf847b47 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -293,6 +293,8 @@ static blk_qc_t md_make_request(struct request_queue *q, struct bio *bio)
* go away inside make_request
*/
sectors = bio_sectors(bio);
+ /* bio could be mergeable after passing to underlayer */
+ bio->bi_rw &= ~REQ_NOMERGE;
mddev->pers->make_request(mddev, bio);
cpu = part_stat_lock();