Firstly bio_clone_mddev() is used in raid normal I/O and isn't in resync I/O path. Secondly all the direct access to bvec table in raid happens on resync I/O except for write behind of raid1, in which we still use bio_clone() for allocating new bvec table. So this patch replaces bio_clone() with bio_clone_fast() in bio_clone_mddev(). Signed-off-by: Ming Lei <tom.leiming@xxxxxxxxx> --- drivers/md/md.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 704be11355a9..7d176f025add 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -193,10 +193,14 @@ EXPORT_SYMBOL_GPL(bio_alloc_mddev); struct bio *bio_clone_mddev(struct bio *bio, gfp_t gfp_mask, struct mddev *mddev) { + struct bio_set *bs; + if (!mddev || !mddev->bio_set) - return bio_clone(bio, gfp_mask); + bs = fs_bio_set; + else + bs = mddev->bio_set; - return bio_clone_bioset(bio, gfp_mask, mddev->bio_set); + return bio_clone_fast(bio, gfp_mask, bs); } EXPORT_SYMBOL_GPL(bio_clone_mddev); -- 2.7.4