From de76fd893074ab2cea132c28ac9efd9d0434215e Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 2 Feb 2021 18:19:23 +0100 Subject: block: remove the 1 and 4 vec bvec_slabs entries All bios with up to 4 bvecs use the inline bvecs in the bio itself, so don't bother to define bvec_slabs entries for them. Also decruftify the bvec_slabs definition and initialization while we're at it. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/bio.c | 53 ++++++++++++++++------------------------------------- 1 file changed, 16 insertions(+), 37 deletions(-) (limited to 'block/bio.c') diff --git a/block/bio.c b/block/bio.c index 321b3479a154..ae241252ea14 100644 --- a/block/bio.c +++ b/block/bio.c @@ -25,23 +25,17 @@ #include "blk.h" #include "blk-rq-qos.h" -struct biovec_slab { +static struct biovec_slab { int nr_vecs; char *name; struct kmem_cache *slab; +} bvec_slabs[] __read_mostly = { + { .nr_vecs = 16, .name = "biovec-16" }, + { .nr_vecs = 64, .name = "biovec-64" }, + { .nr_vecs = 128, .name = "biovec-128" }, + { .nr_vecs = BIO_MAX_PAGES, .name = "biovec-max" }, }; -/* - * if you change this list, also change bvec_alloc or things will - * break badly! cannot be bigger than what you can fit into an - * unsigned short - */ -#define BV(x, n) { .nr_vecs = x, .name = "biovec-"#n } -static struct biovec_slab bvec_slabs[BVEC_POOL_NR] __read_mostly = { - BV(1, 1), BV(4, 4), BV(16, 16), BV(64, 64), BV(128, 128), BV(BIO_MAX_PAGES, max), -}; -#undef BV - /* * fs_bio_set is the bio_set containing bio and iovec memory pools used by * IO code that does not need private memory pools. @@ -176,12 +170,7 @@ struct bio_vec *bvec_alloc(gfp_t gfp_mask, int nr, unsigned long *idx, * see comment near bvec_array define! */ switch (nr) { - case 1: - *idx = 0; - break; - case 2 ... 4: - *idx = 1; - break; + /* smaller bios use inline vecs */ case 5 ... 16: *idx = 2; break; @@ -1613,31 +1602,21 @@ int bioset_init_from_src(struct bio_set *bs, struct bio_set *src) } EXPORT_SYMBOL(bioset_init_from_src); -static void __init biovec_init_slabs(void) +static int __init init_bio(void) { int i; - for (i = 0; i < BVEC_POOL_NR; i++) { - int size; - struct biovec_slab *bvs = bvec_slabs + i; - - if (bvs->nr_vecs <= BIO_INLINE_VECS) { - bvs->slab = NULL; - continue; - } - - size = bvs->nr_vecs * sizeof(struct bio_vec); - bvs->slab = kmem_cache_create(bvs->name, size, 0, - SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); - } -} - -static int __init init_bio(void) -{ BUILD_BUG_ON(BIO_FLAG_LAST > BVEC_POOL_OFFSET); bio_integrity_init(); - biovec_init_slabs(); + + for (i = 0; i < ARRAY_SIZE(bvec_slabs); i++) { + struct biovec_slab *bvs = bvec_slabs + i; + + bvs->slab = kmem_cache_create(bvs->name, + bvs->nr_vecs * sizeof(struct bio_vec), 0, + SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL); + } if (bioset_init(&fs_bio_set, BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS)) panic("bio: can't allocate bios\n"); -- cgit v1.2.3-59-g8ed1b