From d0d9c7e547306caa5aa9687153aaf47b7ac2d3f6 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Mon, 11 Jan 2021 11:05:54 +0800 Subject: [PATCH] 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: Christoph Hellwig Signed-off-by: Ming Lei Reviewed-by: Pavel Begunkov Tested-by: Pavel Begunkov Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe --- block/bio.c | 7 +++++-- include/linux/bio.h | 1 + 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/block/bio.c b/block/bio.c index 87bf16460e0ea..8ccda51dd831b 100644 --- a/block/bio.c +++ b/block/bio.c @@ -89,8 +89,7 @@ fail_alloc_slab: 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); diff --git a/include/linux/bio.h b/include/linux/bio.h index 2f1155eabaff2..5d8977aafa199 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -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 -- 2.39.5