Hi Jens, This series cleans up various lose ends in the bvec allocator.
bvec_alloc always uses biovec_slabs, and thus always needs to use the same number of inline vecs. Share a single definition for the data and integrity bvecs. Signed-off-by: Christoph Hellwig <hch@lst.de> --- block/bio-integrity.c | 6 ++---- block/bio.c | 6 ------ block/blk.h | 1 + 3 files changed, 3 insertions(+), 10 deletions(-) diff --git a/block/bio-integrity.c b/block/bio-integrity.c index c3e5abcfdc98c3..19617fa326c35f 100644 --- a/block/bio-integrity.c +++ b/block/bio-integrity.c @@ -14,8 +14,6 @@ #include <linux/slab.h> #include "blk.h" -#define BIP_INLINE_VECS 4 - static struct kmem_cache *bip_slab; static struct workqueue_struct *kintegrityd_wq; @@ -63,7 +61,7 @@ struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio, inline_vecs = nr_vecs; } else { bip = mempool_alloc(&bs->bio_integrity_pool, gfp_mask); - inline_vecs = BIP_INLINE_VECS; + inline_vecs = BIO_INLINE_VECS; } if (unlikely(!bip)) @@ -470,6 +468,6 @@ void __init bio_integrity_init(void) bip_slab = kmem_cache_create("bio_integrity_payload", sizeof(struct bio_integrity_payload) + - sizeof(struct bio_vec) * BIP_INLINE_VECS, + sizeof(struct bio_vec) * BIO_INLINE_VECS, 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); } diff --git a/block/bio.c b/block/bio.c index 757fee46cefc79..cee2d310f02e78 100644 --- a/block/bio.c +++ b/block/bio.c @@ -25,12 +25,6 @@ #include "blk.h" #include "blk-rq-qos.h" -/* - * Test patch to inline a certain number of bi_io_vec's inside the bio - * itself, to shrink a bio data allocation from two mempool calls to one - */ -#define BIO_INLINE_VECS 4 - /* * if you change this list, also change bvec_alloc or things will * break badly! cannot be bigger than what you can fit into an diff --git a/block/blk.h b/block/blk.h index 0198335c583881..e022a0d0f2ce45 100644 --- a/block/blk.h +++ b/block/blk.h @@ -55,6 +55,7 @@ void blk_free_flush_queue(struct blk_flush_queue *q); void blk_freeze_queue(struct request_queue *q); +#define BIO_INLINE_VECS 4 struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *); void bvec_free(mempool_t *, struct bio_vec *, unsigned int); unsigned int bvec_nr_vecs(unsigned short idx); -- 2.29.2
struct biovec_slab is only used inside of bio.c, so move it there. Signed-off-by: Christoph Hellwig <hch@lst.de> --- block/bio.c | 6 ++++++ include/linux/bio.h | 6 ------ 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/block/bio.c b/block/bio.c index cee2d310f02e78..2c359dadfdf6dc 100644 --- a/block/bio.c +++ b/block/bio.c @@ -25,6 +25,12 @@ #include "blk.h" #include "blk-rq-qos.h" +struct biovec_slab { + int nr_vecs; + char *name; + struct kmem_cache *slab; +}; + /* * if you change this list, also change bvec_alloc or things will * break badly! cannot be bigger than what you can fit into an diff --git a/include/linux/bio.h b/include/linux/bio.h index c74857cf12528c..4a84207dd99663 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -720,12 +720,6 @@ struct bio_set { struct workqueue_struct *rescue_workqueue; }; -struct biovec_slab { - int nr_vecs; - char *name; - struct kmem_cache *slab; -}; - static inline bool bioset_initialized(struct bio_set *bs) { return bs->bio_slab != NULL; -- 2.29.2
Clean up bvec_alloc a little by factoring out a helper for the gfp_t manipulations. Signed-off-by: Christoph Hellwig <hch@lst.de> --- block/bio.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/block/bio.c b/block/bio.c index 2c359dadfdf6dc..c2152c4bf8a317 100644 --- a/block/bio.c +++ b/block/bio.c @@ -159,6 +159,16 @@ void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned int idx) } } +/* + * Make the first allocation restricted and don't dump info on allocation + * failures, since we'll fall back to the mempool in case of failure. + */ +static inline gfp_t bvec_alloc_gfp(gfp_t gfp) +{ + return (gfp & ~(__GFP_DIRECT_RECLAIM | __GFP_IO)) | + __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN; +} + struct bio_vec *bvec_alloc(gfp_t gfp_mask, int nr, unsigned long *idx, mempool_t *pool) { @@ -199,20 +209,12 @@ struct bio_vec *bvec_alloc(gfp_t gfp_mask, int nr, unsigned long *idx, bvl = mempool_alloc(pool, gfp_mask); } else { struct biovec_slab *bvs = bvec_slabs + *idx; - gfp_t __gfp_mask = gfp_mask & ~(__GFP_DIRECT_RECLAIM | __GFP_IO); - - /* - * Make this allocation restricted and don't dump info on - * allocation failures, since we'll fallback to the mempool - * in case of failure. - */ - __gfp_mask |= __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN; /* * 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, __gfp_mask); + bvl = kmem_cache_alloc(bvs->slab, bvec_alloc_gfp(gfp_mask)); if (unlikely(!bvl && (gfp_mask & __GFP_DIRECT_RECLAIM))) { *idx = BVEC_POOL_MAX; goto fallback; -- 2.29.2
Avoid the pointless goto by trying the slab allocation first and falling through to the mempool. Signed-off-by: Christoph Hellwig <hch@lst.de> --- block/bio.c | 26 ++++++++++---------------- 1 file changed, 10 insertions(+), 16 deletions(-) diff --git a/block/bio.c b/block/bio.c index c2152c4bf8a317..321b3479a154da 100644 --- a/block/bio.c +++ b/block/bio.c @@ -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, mempool_t *pool) { - struct bio_vec *bvl; - /* * 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 - * 1-vec entry pool is mempool backed. + * Try a slab allocation first for all smaller allocations. If that + * 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) { -fallback: - bvl = mempool_alloc(pool, gfp_mask); - } else { + if (*idx < BVEC_POOL_MAX) { 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)); - if (unlikely(!bvl && (gfp_mask & __GFP_DIRECT_RECLAIM))) { - *idx = BVEC_POOL_MAX; - goto fallback; + if (likely(bvl) || !(gfp_mask & __GFP_DIRECT_RECLAIM)) { + (*idx)++; + return bvl; } + *idx = BVEC_POOL_MAX; } (*idx)++; - return bvl; + return mempool_alloc(pool, gfp_mask); } void bio_uninit(struct bio *bio) -- 2.29.2
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 <hch@lst.de> --- block/bio.c | 53 ++++++++++++++++------------------------------------- 1 file changed, 16 insertions(+), 37 deletions(-) diff --git a/block/bio.c b/block/bio.c index 321b3479a154da..ae241252ea14e5 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"); -- 2.29.2
The bi_max_vecs and bi_vcnt fields are defined as unsigned short, so don't allow passing larger values in. Signed-off-by: Christoph Hellwig <hch@lst.de> --- block/bio.c | 4 ++-- include/linux/bio.h | 7 ++++--- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/block/bio.c b/block/bio.c index ae241252ea14e5..3d28d4723f6f2f 100644 --- a/block/bio.c +++ b/block/bio.c @@ -407,7 +407,7 @@ static void punt_bios_to_rescuer(struct bio_set *bs) * * Returns: Pointer to new bio on success, NULL on failure. */ -struct bio *bio_alloc_bioset(gfp_t gfp_mask, unsigned int nr_iovecs, +struct bio *bio_alloc_bioset(gfp_t gfp_mask, unsigned short nr_iovecs, struct bio_set *bs) { gfp_t saved_gfp = gfp_mask; @@ -493,7 +493,7 @@ EXPORT_SYMBOL(bio_alloc_bioset); * * Returns: Pointer to new bio on success, NULL on failure. */ -struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs) +struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned short nr_iovecs) { struct bio *bio; diff --git a/include/linux/bio.h b/include/linux/bio.h index 4a84207dd99663..9ceeb8ecdb7f23 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -407,8 +407,9 @@ extern void bioset_exit(struct bio_set *); extern int biovec_init_pool(mempool_t *pool, int pool_entries); extern int bioset_init_from_src(struct bio_set *bs, struct bio_set *src); -extern struct bio *bio_alloc_bioset(gfp_t, unsigned int, struct bio_set *); -struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs); +struct bio *bio_alloc_bioset(gfp_t gfp, unsigned short nr_iovecs, + struct bio_set *bs); +struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned short nr_iovecs); extern void bio_put(struct bio *); extern void __bio_clone_fast(struct bio *, struct bio *); @@ -416,7 +417,7 @@ extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *); extern struct bio_set fs_bio_set; -static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs) +static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned short nr_iovecs) { return bio_alloc_bioset(gfp_mask, nr_iovecs, &fs_bio_set); } -- 2.29.2
Remove a pointless layer of indentation after a return statement. Signed-off-by: Christoph Hellwig <hch@lst.de> --- block/bio.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/block/bio.c b/block/bio.c index 3d28d4723f6f2f..dd3b2a01c9bfaa 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1081,15 +1081,15 @@ int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) bio_iov_bvec_set(bio, iter); bio_set_flag(bio, BIO_NO_PAGE_REF); return 0; - } else { - do { - if (bio_op(bio) == REQ_OP_ZONE_APPEND) - ret = __bio_iov_append_get_pages(bio, iter); - else - ret = __bio_iov_iter_get_pages(bio, iter); - } while (!ret && iov_iter_count(iter) && !bio_full(bio, 0)); } + do { + if (bio_op(bio) == REQ_OP_ZONE_APPEND) + ret = __bio_iov_append_get_pages(bio, iter); + else + ret = __bio_iov_iter_get_pages(bio, iter); + } while (!ret && iov_iter_count(iter) && !bio_full(bio, 0)); + /* don't account direct I/O as memory stall */ bio_clear_flag(bio, BIO_WORKINGSET); return bio->bi_vcnt ? 0 : ret; -- 2.29.2
bio_iov_bvec_set assigns the foreign bvec, so setting the NO_PAGE_REF directly there seems like the best fit. Signed-off-by: Christoph Hellwig <hch@lst.de> --- block/bio.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/block/bio.c b/block/bio.c index dd3b2a01c9bfaa..f753201238273b 100644 --- a/block/bio.c +++ b/block/bio.c @@ -941,6 +941,7 @@ static int bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter) bio->bi_io_vec = (struct bio_vec *)iter->bvec; bio->bi_iter.bi_bvec_done = iter->iov_offset; bio->bi_iter.bi_size = iter->count; + bio_set_flag(bio, BIO_NO_PAGE_REF); iov_iter_advance(iter, iter->count); return 0; @@ -1078,9 +1079,7 @@ int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) if (iov_iter_is_bvec(iter)) { if (WARN_ON_ONCE(bio_op(bio) == REQ_OP_ZONE_APPEND)) return -EINVAL; - bio_iov_bvec_set(bio, iter); - bio_set_flag(bio, BIO_NO_PAGE_REF); - return 0; + return bio_iov_bvec_set(bio, iter); } do { -- 2.29.2
bio_iov_bvec_set clones the bio_vecs from the iter, and thus should be treated like a cloned bio in every respect. That also includes not touching bi_max_vecs as that is a property of the bio allocation and not its current payload. Signed-off-by: Christoph Hellwig <hch@lst.de> --- block/bio.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/bio.c b/block/bio.c index f753201238273b..a36f955cd120b0 100644 --- a/block/bio.c +++ b/block/bio.c @@ -937,11 +937,11 @@ static int bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter) WARN_ON_ONCE(BVEC_POOL_IDX(bio) != 0); bio->bi_vcnt = iter->nr_segs; - bio->bi_max_vecs = iter->nr_segs; bio->bi_io_vec = (struct bio_vec *)iter->bvec; bio->bi_iter.bi_bvec_done = iter->iov_offset; bio->bi_iter.bi_size = iter->count; bio_set_flag(bio, BIO_NO_PAGE_REF); + bio_set_flag(bio, BIO_CLONED); iov_iter_advance(iter, iter->count); return 0; -- 2.29.2
A bio allocated by bio_alloc_bioset comes pre-zeroed, no need to clear random fields. Signed-off-by: Christoph Hellwig <hch@lst.de> --- drivers/md/raid10.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index e1eefbec15d444..a9ae7d113492c9 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -4539,10 +4539,6 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, read_bio->bi_private = r10_bio; read_bio->bi_end_io = end_reshape_read; bio_set_op_attrs(read_bio, REQ_OP_READ, 0); - read_bio->bi_flags &= (~0UL << BIO_RESET_BITS); - read_bio->bi_status = 0; - read_bio->bi_vcnt = 0; - read_bio->bi_iter.bi_size = 0; r10_bio->master_bio = read_bio; r10_bio->read_slot = r10_bio->devs[r10_bio->read_slot].devnum; -- 2.29.2
Instead of encoding of the bvec pool using magic bio flags, just use a helper to find the pool based on the max_vecs value. Signed-off-by: Christoph Hellwig <hch@lst.de> --- block/bio-integrity.c | 11 ++-- block/bio.c | 104 ++++++++++++++++---------------------- block/blk.h | 6 +-- include/linux/bio.h | 1 - include/linux/blk_types.h | 29 +---------- 5 files changed, 51 insertions(+), 100 deletions(-) diff --git a/block/bio-integrity.c b/block/bio-integrity.c index 19617fa326c35f..dfa652122a2dc8 100644 --- a/block/bio-integrity.c +++ b/block/bio-integrity.c @@ -28,7 +28,7 @@ static void __bio_integrity_free(struct bio_set *bs, if (bs && mempool_initialized(&bs->bio_integrity_pool)) { if (bip->bip_vec) bvec_free(&bs->bvec_integrity_pool, bip->bip_vec, - bip->bip_slab); + bip->bip_max_vcnt); mempool_free(bip, &bs->bio_integrity_pool); } else { kfree(bip); @@ -70,14 +70,11 @@ struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio, memset(bip, 0, sizeof(*bip)); if (nr_vecs > inline_vecs) { - unsigned long idx = 0; - - bip->bip_vec = bvec_alloc(gfp_mask, nr_vecs, &idx, - &bs->bvec_integrity_pool); + bip->bip_max_vcnt = nr_vecs; + bip->bip_vec = bvec_alloc(&bs->bvec_integrity_pool, + &bip->bip_max_vcnt, gfp_mask); if (!bip->bip_vec) goto err; - bip->bip_max_vcnt = bvec_nr_vecs(idx); - bip->bip_slab = idx; } else { bip->bip_vec = bip->bip_inline_vecs; bip->bip_max_vcnt = inline_vecs; diff --git a/block/bio.c b/block/bio.c index a36f955cd120b0..a0eabe2f8b07a5 100644 --- a/block/bio.c +++ b/block/bio.c @@ -36,6 +36,24 @@ static struct biovec_slab { { .nr_vecs = BIO_MAX_PAGES, .name = "biovec-max" }, }; +static struct biovec_slab *biovec_slab(unsigned short nr_vecs) +{ + switch (nr_vecs) { + /* smaller bios use inline vecs */ + case 5 ... 16: + return &bvec_slabs[0]; + case 17 ... 64: + return &bvec_slabs[1]; + case 65 ... 128: + return &bvec_slabs[2]; + case 129 ... BIO_MAX_PAGES: + return &bvec_slabs[3]; + default: + BUG(); + return NULL; + } +} + /* * fs_bio_set is the bio_set containing bio and iovec memory pools used by * IO code that does not need private memory pools. @@ -131,26 +149,14 @@ static void bio_put_slab(struct bio_set *bs) mutex_unlock(&bio_slab_lock); } -unsigned int bvec_nr_vecs(unsigned short idx) +void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned short nr_vecs) { - return bvec_slabs[--idx].nr_vecs; -} + BIO_BUG_ON(nr_vecs > BIO_MAX_PAGES); -void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned int idx) -{ - if (!idx) - return; - idx--; - - BIO_BUG_ON(idx >= BVEC_POOL_NR); - - if (idx == BVEC_POOL_MAX) { + if (nr_vecs == BIO_MAX_PAGES) mempool_free(bv, pool); - } else { - struct biovec_slab *bvs = bvec_slabs + idx; - - kmem_cache_free(bvs->slab, bv); - } + else if (nr_vecs > BIO_INLINE_VECS) + kmem_cache_free(biovec_slab(nr_vecs)->slab, bv); } /* @@ -163,48 +169,34 @@ static inline gfp_t bvec_alloc_gfp(gfp_t gfp) __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN; } -struct bio_vec *bvec_alloc(gfp_t gfp_mask, int nr, unsigned long *idx, - mempool_t *pool) +struct bio_vec *bvec_alloc(mempool_t *pool, unsigned short *nr_vecs, + gfp_t gfp_mask) { + struct biovec_slab *bvs = biovec_slab(*nr_vecs); + + if (WARN_ON_ONCE(!bvs)) + return NULL; + /* - * see comment near bvec_array define! + * Upgrade the nr_vecs request to take full advantage of the allocation. + * We also rely on this in the bvec_free path. */ - switch (nr) { - /* smaller bios use inline vecs */ - case 5 ... 16: - *idx = 2; - break; - case 17 ... 64: - *idx = 3; - break; - case 65 ... 128: - *idx = 4; - break; - case 129 ... BIO_MAX_PAGES: - *idx = 5; - break; - default: - return NULL; - } + *nr_vecs = bvs->nr_vecs; /* * Try a slab allocation first for all smaller allocations. If that * 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) { - struct biovec_slab *bvs = bvec_slabs + *idx; + if (*nr_vecs < BIO_MAX_PAGES) { struct bio_vec *bvl; bvl = kmem_cache_alloc(bvs->slab, bvec_alloc_gfp(gfp_mask)); - if (likely(bvl) || !(gfp_mask & __GFP_DIRECT_RECLAIM)) { - (*idx)++; + if (likely(bvl) || !(gfp_mask & __GFP_DIRECT_RECLAIM)) return bvl; - } - *idx = BVEC_POOL_MAX; + *nr_vecs = BIO_MAX_PAGES; } - (*idx)++; return mempool_alloc(pool, gfp_mask); } @@ -231,7 +223,7 @@ static void bio_free(struct bio *bio) bio_uninit(bio); if (bs) { - bvec_free(&bs->bvec_pool, bio->bi_io_vec, BVEC_POOL_IDX(bio)); + bvec_free(&bs->bvec_pool, bio->bi_io_vec, bio->bi_max_vecs); /* * If we have front padding, adjust the bio pointer before freeing @@ -275,12 +267,8 @@ EXPORT_SYMBOL(bio_init); */ void bio_reset(struct bio *bio) { - unsigned long flags = bio->bi_flags & (~0UL << BIO_RESET_BITS); - bio_uninit(bio); - memset(bio, 0, BIO_RESET_BYTES); - bio->bi_flags = flags; atomic_set(&bio->__bi_remaining, 1); } EXPORT_SYMBOL(bio_reset); @@ -453,22 +441,18 @@ struct bio *bio_alloc_bioset(gfp_t gfp_mask, unsigned short nr_iovecs, bio = p + bs->front_pad; if (nr_iovecs > BIO_INLINE_VECS) { - unsigned long idx = 0; struct bio_vec *bvl = NULL; - bvl = bvec_alloc(gfp_mask, nr_iovecs, &idx, &bs->bvec_pool); + bvl = bvec_alloc(&bs->bvec_pool, &nr_iovecs, gfp_mask); if (!bvl && gfp_mask != saved_gfp) { punt_bios_to_rescuer(bs); gfp_mask = saved_gfp; - bvl = bvec_alloc(gfp_mask, nr_iovecs, &idx, - &bs->bvec_pool); + bvl = bvec_alloc(&bs->bvec_pool, &nr_iovecs, gfp_mask); } - if (unlikely(!bvl)) goto err_free; - bio_init(bio, bvl, bvec_nr_vecs(idx)); - bio->bi_flags |= idx << BVEC_POOL_OFFSET; + bio_init(bio, bvl, nr_iovecs); } else if (nr_iovecs) { bio_init(bio, bio->bi_inline_vecs, BIO_INLINE_VECS); } else { @@ -644,7 +628,7 @@ EXPORT_SYMBOL(bio_put); */ void __bio_clone_fast(struct bio *bio, struct bio *bio_src) { - BUG_ON(bio->bi_pool && BVEC_POOL_IDX(bio)); + WARN_ON_ONCE(bio->bi_pool && bio->bi_max_vecs); /* * most users will be overriding ->bi_bdev with a new target, @@ -934,7 +918,7 @@ EXPORT_SYMBOL_GPL(bio_release_pages); static int bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter) { - WARN_ON_ONCE(BVEC_POOL_IDX(bio) != 0); + WARN_ON_ONCE(bio->bi_max_vecs); bio->bi_vcnt = iter->nr_segs; bio->bi_io_vec = (struct bio_vec *)iter->bvec; @@ -1495,7 +1479,7 @@ EXPORT_SYMBOL_GPL(bio_trim); */ int biovec_init_pool(mempool_t *pool, int pool_entries) { - struct biovec_slab *bp = bvec_slabs + BVEC_POOL_MAX; + struct biovec_slab *bp = bvec_slabs + ARRAY_SIZE(bvec_slabs) - 1; return mempool_init_slab_pool(pool, pool_entries, bp->slab); } @@ -1605,8 +1589,6 @@ static int __init init_bio(void) { int i; - BUILD_BUG_ON(BIO_FLAG_LAST > BVEC_POOL_OFFSET); - bio_integrity_init(); for (i = 0; i < ARRAY_SIZE(bvec_slabs); i++) { diff --git a/block/blk.h b/block/blk.h index e022a0d0f2ce45..bfc4d526f6261c 100644 --- a/block/blk.h +++ b/block/blk.h @@ -56,9 +56,9 @@ void blk_free_flush_queue(struct blk_flush_queue *q); void blk_freeze_queue(struct request_queue *q); #define BIO_INLINE_VECS 4 -struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *); -void bvec_free(mempool_t *, struct bio_vec *, unsigned int); -unsigned int bvec_nr_vecs(unsigned short idx); +struct bio_vec *bvec_alloc(mempool_t *pool, unsigned short *nr_vecs, + gfp_t gfp_mask); +void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned short nr_vecs); static inline bool biovec_phys_mergeable(struct request_queue *q, struct bio_vec *vec1, struct bio_vec *vec2) diff --git a/include/linux/bio.h b/include/linux/bio.h index 9ceeb8ecdb7f23..3cbbaf76906edb 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -329,7 +329,6 @@ struct bio_integrity_payload { struct bvec_iter bip_iter; - unsigned short bip_slab; /* slab the bip came from */ unsigned short bip_vcnt; /* # of integrity bio_vecs */ unsigned short bip_max_vcnt; /* integrity bio_vec slots */ unsigned short bip_flags; /* control flags */ diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 1bc6f6a01070fc..db026b6ec15ab7 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -227,7 +227,7 @@ struct bio { * top bits REQ_OP. Use * accessors. */ - unsigned short bi_flags; /* status, etc and bvec pool number */ + unsigned short bi_flags; /* BIO_* below */ unsigned short bi_ioprio; unsigned short bi_write_hint; blk_status_t bi_status; @@ -307,33 +307,6 @@ enum { BIO_FLAG_LAST }; -/* See BVEC_POOL_OFFSET below before adding new flags */ - -/* - * We support 6 different bvec pools, the last one is magic in that it - * is backed by a mempool. - */ -#define BVEC_POOL_NR 6 -#define BVEC_POOL_MAX (BVEC_POOL_NR - 1) - -/* - * Top 3 bits of bio flags indicate the pool the bvecs came from. We add - * 1 to the actual index so that 0 indicates that there are no bvecs to be - * freed. - */ -#define BVEC_POOL_BITS (3) -#define BVEC_POOL_OFFSET (16 - BVEC_POOL_BITS) -#define BVEC_POOL_IDX(bio) ((bio)->bi_flags >> BVEC_POOL_OFFSET) -#if (1<< BVEC_POOL_BITS) < (BVEC_POOL_NR+1) -# error "BVEC_POOL_BITS is too small" -#endif - -/* - * Flags starting here get preserved by bio_reset() - this includes - * only BVEC_POOL_IDX() - */ -#define BIO_RESET_BITS BVEC_POOL_OFFSET - typedef __u32 __bitwise blk_mq_req_flags_t; /* -- 2.29.2
On Tue, Feb 2, 2021 at 9:19 AM Christoph Hellwig <hch@lst.de> wrote:
>
> A bio allocated by bio_alloc_bioset comes pre-zeroed, no need to
> clear random fields.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
On Tue, Feb 02, 2021 at 06:19:18PM +0100, Christoph Hellwig wrote:
> Hi Jens,
>
> This series cleans up various lose ends in the bvec allocator.
Any comments?
On 2/2/21 10:19 AM, Christoph Hellwig wrote:
> Hi Jens,
>
> This series cleans up various lose ends in the bvec allocator.
Applied, thanks.
--
Jens Axboe