Commit 9f180e31 authored by Ming Lei's avatar Ming Lei Committed by Jens Axboe
Browse files

block: don't allocate inline bvecs if this bioset needn't bvecs 



The inline bvecs won't be used if user needn't bvecs by not passing
BIOSET_NEED_BVECS, so don't allocate bvecs in this situation.

Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarMing Lei <ming.lei@redhat.com>
Reviewed-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Tested-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent c495a176

block/bio.c

+5 −2
Original line number Diff line number Diff line
@@ -89,8 +89,7 @@ static struct bio_slab *create_bio_slab(unsigned int size) 


static inline unsigned int bs_bio_slab_size(struct bio_set *bs)

{

	return bs->front_pad + sizeof(struct bio) +

		BIO_INLINE_VECS * sizeof(struct bio_vec);

	return bs->front_pad + sizeof(struct bio) + bs->back_pad;

}



static struct kmem_cache *bio_find_or_create_slab(struct bio_set *bs)
@@ -1563,6 +1562,10 @@ int bioset_init(struct bio_set *bs, 
		int flags)

{

	bs->front_pad = front_pad;

	if (flags & BIOSET_NEED_BVECS)

		bs->back_pad = BIO_INLINE_VECS * sizeof(struct bio_vec);

	else

		bs->back_pad = 0;



	spin_lock_init(&bs->rescue_lock);

	bio_list_init(&bs->rescue_list);

include/linux/bio.h

+1 −0
Original line number Diff line number Diff line
@@ -703,6 +703,7 @@ struct bio_set { 
	mempool_t bvec_integrity_pool;

#endif



	unsigned int back_pad;

	/*

	 * Deadlock avoidance for stacking block drivers: see comments in

	 * bio_alloc_bioset() for details