ich777/linux_media
1
0
Fork 0
mirror of https://github.com/tbsdtv/linux_media.git synced 2025-07-23 20:51:03 +02:00
Code Issues Packages Projects Releases Wiki Activity

block: streamline bvec_alloc

Browse Source 
Avoid the pointless goto by trying the slab allocation first and falling
through to the mempool.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig
2021-02-02 18:19:22 +01:00
committed by Jens Axboe
parent f2c3eb9bb0
commit f007a3d66c
1 changed files with 10 additions and 16 deletions
Download Patch File Download Diff File Expand all files Collapse all files

26
block/bio.c
View File

@@ -172,8 +172,6 @@ static inline gfp_t bvec_alloc_gfp(gfp_t gfp)
struct bio_vec *bvec_alloc(gfp_t gfp_mask, int nr, unsigned long *idx, struct bio_vec *bvec_alloc(gfp_t gfp_mask, int nr, unsigned long *idx,
mempool_t *pool) mempool_t *pool)
{ {
struct bio_vec *bvl;
/* /*
* see comment near bvec_array define! * see comment near bvec_array define!
*/ */
@@ -201,28 +199,24 @@ struct bio_vec *bvec_alloc(gfp_t gfp_mask, int nr, unsigned long *idx,
} }
/* /*
* idx now points to the pool we want to allocate from. only the * Try a slab allocation first for all smaller allocations. If that
* 1-vec entry pool is mempool backed. * fails and __GFP_DIRECT_RECLAIM is set retry with the mempool.
* The mempool is sized to handle up to BIO_MAX_PAGES entries.
*/ */
if (*idx == BVEC_POOL_MAX) { if (*idx < BVEC_POOL_MAX) {
fallback:
bvl = mempool_alloc(pool, gfp_mask);
} else {
struct biovec_slab *bvs = bvec_slabs + *idx; struct biovec_slab *bvs = bvec_slabs + *idx;
struct bio_vec *bvl;
/*
* Try a slab allocation. If this fails and __GFP_DIRECT_RECLAIM
* is set, retry with the 1-entry mempool
*/
bvl = kmem_cache_alloc(bvs->slab, bvec_alloc_gfp(gfp_mask)); bvl = kmem_cache_alloc(bvs->slab, bvec_alloc_gfp(gfp_mask));
if (unlikely(!bvl && (gfp_mask & __GFP_DIRECT_RECLAIM))) { if (likely(bvl) || !(gfp_mask & __GFP_DIRECT_RECLAIM)) {
*idx = BVEC_POOL_MAX; (*idx)++;
goto fallback; return bvl;
} }
*idx = BVEC_POOL_MAX;
} }
(*idx)++; (*idx)++;
return bvl; return mempool_alloc(pool, gfp_mask);
} }
void bio_uninit(struct bio *bio) void bio_uninit(struct bio *bio)