From 0df71650c051ab106c921de257f4b38e9e3dd251 Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Thu, 24 Mar 2022 16:35:24 -0400 Subject: block: allow using the per-cpu bio cache from bio_alloc_bioset Replace the BIO_PERCPU_CACHE bio-internal flag with a REQ_ALLOC_CACHE one that can be passed to bio_alloc / bio_alloc_bioset, and implement the percpu cache allocation logic in a helper called from bio_alloc_bioset. This allows any bio_alloc_bioset user to use the percpu caches instead of having the functionality tied to struct kiocb. Signed-off-by: Mike Snitzer [hch: refactored a bit] Signed-off-by: Christoph Hellwig Link: https://lore.kernel.org/r/20220324203526.62306-2-snitzer@kernel.org Signed-off-by: Jens Axboe --- block/bio.c | 86 +++++++++++++++++++++++++++++-------------------------------- 1 file changed, 41 insertions(+), 45 deletions(-) (limited to 'block/bio.c') diff --git a/block/bio.c b/block/bio.c index 4259125e16ab..c67f47c6cc8c 100644 --- a/block/bio.c +++ b/block/bio.c @@ -419,6 +419,28 @@ static void punt_bios_to_rescuer(struct bio_set *bs) queue_work(bs->rescue_workqueue, &bs->rescue_work); } +static struct bio *bio_alloc_percpu_cache(struct block_device *bdev, + unsigned short nr_vecs, unsigned int opf, gfp_t gfp, + struct bio_set *bs) +{ + struct bio_alloc_cache *cache; + struct bio *bio; + + cache = per_cpu_ptr(bs->cache, get_cpu()); + if (!cache->free_list) { + put_cpu(); + return NULL; + } + bio = cache->free_list; + cache->free_list = bio->bi_next; + cache->nr--; + put_cpu(); + + bio_init(bio, bdev, nr_vecs ? bio->bi_inline_vecs : NULL, nr_vecs, opf); + bio->bi_pool = bs; + return bio; +} + /** * bio_alloc_bioset - allocate a bio for I/O * @bdev: block device to allocate the bio for (can be %NULL) @@ -451,6 +473,9 @@ static void punt_bios_to_rescuer(struct bio_set *bs) * submit_bio_noacct() should be avoided - instead, use bio_set's front_pad * for per bio allocations. * + * If REQ_ALLOC_CACHE is set, the final put of the bio MUST be done from process + * context, not hard/soft IRQ. + * * Returns: Pointer to new bio on success, NULL on failure. */ struct bio *bio_alloc_bioset(struct block_device *bdev, unsigned short nr_vecs, @@ -465,6 +490,21 @@ struct bio *bio_alloc_bioset(struct block_device *bdev, unsigned short nr_vecs, if (WARN_ON_ONCE(!mempool_initialized(&bs->bvec_pool) && nr_vecs > 0)) return NULL; + if (opf & REQ_ALLOC_CACHE) { + if (bs->cache && nr_vecs <= BIO_INLINE_VECS) { + bio = bio_alloc_percpu_cache(bdev, nr_vecs, opf, + gfp_mask, bs); + if (bio) + return bio; + /* + * No cached bio available, bio returned below marked with + * REQ_ALLOC_CACHE to particpate in per-cpu alloc cache. + */ + } else { + opf &= ~REQ_ALLOC_CACHE; + } + } + /* * submit_bio_noacct() converts recursion to iteration; this means if * we're running beneath it, any bios we allocate and submit will not be @@ -711,7 +751,7 @@ void bio_put(struct bio *bio) return; } - if (bio_flagged(bio, BIO_PERCPU_CACHE)) { + if (bio->bi_opf & REQ_ALLOC_CACHE) { struct bio_alloc_cache *cache; bio_uninit(bio); @@ -1732,50 +1772,6 @@ int bioset_init_from_src(struct bio_set *bs, struct bio_set *src) } EXPORT_SYMBOL(bioset_init_from_src); -/** - * bio_alloc_kiocb - Allocate a bio from bio_set based on kiocb - * @kiocb: kiocb describing the IO - * @bdev: block device to allocate the bio for (can be %NULL) - * @nr_vecs: number of iovecs to pre-allocate - * @opf: operation and flags for bio - * @bs: bio_set to allocate from - * - * Description: - * Like @bio_alloc_bioset, but pass in the kiocb. The kiocb is only - * used to check if we should dip into the per-cpu bio_set allocation - * cache. The allocation uses GFP_KERNEL internally. On return, the - * bio is marked BIO_PERCPU_CACHEABLE, and the final put of the bio - * MUST be done from process context, not hard/soft IRQ. - * - */ -struct bio *bio_alloc_kiocb(struct kiocb *kiocb, struct block_device *bdev, - unsigned short nr_vecs, unsigned int opf, struct bio_set *bs) -{ - struct bio_alloc_cache *cache; - struct bio *bio; - - if (!(kiocb->ki_flags & IOCB_ALLOC_CACHE) || nr_vecs > BIO_INLINE_VECS) - return bio_alloc_bioset(bdev, nr_vecs, opf, GFP_KERNEL, bs); - - cache = per_cpu_ptr(bs->cache, get_cpu()); - if (cache->free_list) { - bio = cache->free_list; - cache->free_list = bio->bi_next; - cache->nr--; - put_cpu(); - bio_init(bio, bdev, nr_vecs ? bio->bi_inline_vecs : NULL, - nr_vecs, opf); - bio->bi_pool = bs; - bio_set_flag(bio, BIO_PERCPU_CACHE); - return bio; - } - put_cpu(); - bio = bio_alloc_bioset(bdev, nr_vecs, opf, GFP_KERNEL, bs); - bio_set_flag(bio, BIO_PERCPU_CACHE); - return bio; -} -EXPORT_SYMBOL_GPL(bio_alloc_kiocb); - static int __init init_bio(void) { int i; -- cgit v1.2.3