block: check bio_mergeable() early before merging
authorMing Lei <ming.lei@canonical.com>
Tue, 20 Oct 2015 15:13:55 +0000 (23:13 +0800)
committerJens Axboe <axboe@fb.com>
Wed, 21 Oct 2015 21:00:54 +0000 (15:00 -0600)
commit7460d389c01741f0dfff733af93d3b3abd9b974e
treeec3904b3fab8e38bb5b2c583cdde993ef2d7f451
parente18378a60e27ad7b3e11ecc4e2c92159585dee68
block: check bio_mergeable() early before merging

After bio splitting is introduced, one bio can be splitted
and it is marked as NOMERGE because it is too fat to be merged,
so check bio_mergeable() earlier to avoid to try to merge it
unnecessarily.

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
block/elevator.c