[PATCH v6 01/13] block: Generalized bio pool freeing
From: Kent Overstreet <hidden>
Date: 2012-08-22 17:07:53
Also in:
dm-devel, lkml
Subsystem:
block layer, device-mapper (lvm), drbd driver, filesystems (vfs and infrastructure), scsi target subsystem, software raid (multiple disks) support, the rest · Maintainers:
Jens Axboe, Alasdair Kergon, Mike Snitzer, Mikulas Patocka, Benjamin Marzinski, Philipp Reisner, Lars Ellenberg, Christoph Böhmwalder, Alexander Viro, Christian Brauner, "Martin K. Petersen", Song Liu, Yu Kuai, Linus Torvalds
With the old code, when you allocate a bio from a bio pool you have to implement your own destructor that knows how to find the bio pool the bio was originally allocated from. This adds a new field to struct bio (bi_pool) and changes bio_alloc_bioset() to use it. This makes various bio destructors unnecessary, so they're then deleted. v6: Explain the temporary if statement in bio_put Signed-off-by: Kent Overstreet <redacted> CC: Jens Axboe <axboe@kernel.dk> CC: NeilBrown <redacted> CC: Alasdair Kergon <agk@redhat.com> CC: Nicholas Bellinger <redacted> CC: Lars Ellenberg <lars.ellenberg@linbit.com> Acked-by: Tejun Heo <tj@kernel.org> --- drivers/block/drbd/drbd_main.c | 13 +------------ drivers/md/dm-crypt.c | 9 --------- drivers/md/dm-io.c | 11 ----------- drivers/md/dm.c | 20 -------------------- drivers/md/md.c | 28 ++++------------------------ drivers/target/target_core_iblock.c | 9 --------- fs/bio.c | 31 +++++++++++++------------------ include/linux/blk_types.h | 3 +++ 8 files changed, 21 insertions(+), 103 deletions(-)
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index dbe6135..5964459 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c@@ -161,23 +161,12 @@ static const struct block_device_operations drbd_ops = { .release = drbd_release, }; -static void bio_destructor_drbd(struct bio *bio) -{ - bio_free(bio, drbd_md_io_bio_set); -} - struct bio *bio_alloc_drbd(gfp_t gfp_mask) { - struct bio *bio; - if (!drbd_md_io_bio_set) return bio_alloc(gfp_mask, 1); - bio = bio_alloc_bioset(gfp_mask, 1, drbd_md_io_bio_set); - if (!bio) - return NULL; - bio->bi_destructor = bio_destructor_drbd; - return bio; + return bio_alloc_bioset(gfp_mask, 1, drbd_md_io_bio_set); } #ifdef __CHECKER__
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 664743d..3c0acba 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c@@ -798,14 +798,6 @@ static int crypt_convert(struct crypt_config *cc, return 0; } -static void dm_crypt_bio_destructor(struct bio *bio) -{ - struct dm_crypt_io *io = bio->bi_private; - struct crypt_config *cc = io->cc; - - bio_free(bio, cc->bs); -} - /* * Generate a new unfragmented bio with the given size * This should never violate the device limitations
@@ -974,7 +966,6 @@ static void clone_init(struct dm_crypt_io *io, struct bio *clone) clone->bi_end_io = crypt_endio; clone->bi_bdev = cc->dev->bdev; clone->bi_rw = io->base_bio->bi_rw; - clone->bi_destructor = dm_crypt_bio_destructor; } static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c
index ea5dd28..1c46f97 100644
--- a/drivers/md/dm-io.c
+++ b/drivers/md/dm-io.c@@ -249,16 +249,6 @@ static void vm_dp_init(struct dpages *dp, void *data) dp->context_ptr = data; } -static void dm_bio_destructor(struct bio *bio) -{ - unsigned region; - struct io *io; - - retrieve_io_and_region_from_bio(bio, &io, ®ion); - - bio_free(bio, io->client->bios); -} - /* * Functions for getting the pages from kernel memory. */
@@ -317,7 +307,6 @@ static void do_region(int rw, unsigned region, struct dm_io_region *where, bio->bi_sector = where->sector + (where->count - remaining); bio->bi_bdev = where->bdev; bio->bi_end_io = endio; - bio->bi_destructor = dm_bio_destructor; store_io_and_region_in_bio(bio, io, region); if (rw & REQ_DISCARD) {
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 4e09b6f..0c3d6dd 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c@@ -681,11 +681,6 @@ static void clone_endio(struct bio *bio, int error) } } - /* - * Store md for cleanup instead of tio which is about to get freed. - */ - bio->bi_private = md->bs; - free_tio(md, tio); bio_put(bio); dec_pending(io, error);
@@ -1032,11 +1027,6 @@ static void __map_bio(struct dm_target *ti, struct bio *clone, /* error the io and bail out, or requeue it if needed */ md = tio->io->md; dec_pending(tio->io, r); - /* - * Store bio_set for cleanup. - */ - clone->bi_end_io = NULL; - clone->bi_private = md->bs; bio_put(clone); free_tio(md, tio); } else if (r) {
@@ -1055,13 +1045,6 @@ struct clone_info { unsigned short idx; }; -static void dm_bio_destructor(struct bio *bio) -{ - struct bio_set *bs = bio->bi_private; - - bio_free(bio, bs); -} - /* * Creates a little bio that just does part of a bvec. */
@@ -1073,7 +1056,6 @@ static struct bio *split_bvec(struct bio *bio, sector_t sector, struct bio_vec *bv = bio->bi_io_vec + idx; clone = bio_alloc_bioset(GFP_NOIO, 1, bs); - clone->bi_destructor = dm_bio_destructor; *clone->bi_io_vec = *bv; clone->bi_sector = sector;
@@ -1105,7 +1087,6 @@ static struct bio *clone_bio(struct bio *bio, sector_t sector, clone = bio_alloc_bioset(GFP_NOIO, bio->bi_max_vecs, bs); __bio_clone(clone, bio); - clone->bi_destructor = dm_bio_destructor; clone->bi_sector = sector; clone->bi_idx = idx; clone->bi_vcnt = idx + bv_count;
@@ -1150,7 +1131,6 @@ static void __issue_target_request(struct clone_info *ci, struct dm_target *ti, */ clone = bio_alloc_bioset(GFP_NOIO, ci->bio->bi_max_vecs, ci->md->bs); __bio_clone(clone, ci->bio); - clone->bi_destructor = dm_bio_destructor; if (len) { clone->bi_sector = ci->sector; clone->bi_size = to_bytes(len);
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 3f6203a..b8eebe3 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c@@ -155,32 +155,17 @@ static int start_readonly; * like bio_clone, but with a local bio set */ -static void mddev_bio_destructor(struct bio *bio) -{ - struct mddev *mddev, **mddevp; - - mddevp = (void*)bio; - mddev = mddevp[-1]; - - bio_free(bio, mddev->bio_set); -} - struct bio *bio_alloc_mddev(gfp_t gfp_mask, int nr_iovecs, struct mddev *mddev) { struct bio *b; - struct mddev **mddevp; if (!mddev || !mddev->bio_set) return bio_alloc(gfp_mask, nr_iovecs); - b = bio_alloc_bioset(gfp_mask, nr_iovecs, - mddev->bio_set); + b = bio_alloc_bioset(gfp_mask, nr_iovecs, mddev->bio_set); if (!b) return NULL; - mddevp = (void*)b; - mddevp[-1] = mddev; - b->bi_destructor = mddev_bio_destructor; return b; } EXPORT_SYMBOL_GPL(bio_alloc_mddev);
@@ -189,18 +174,14 @@ struct bio *bio_clone_mddev(struct bio *bio, gfp_t gfp_mask, struct mddev *mddev) { struct bio *b; - struct mddev **mddevp; if (!mddev || !mddev->bio_set) return bio_clone(bio, gfp_mask); - b = bio_alloc_bioset(gfp_mask, bio->bi_max_vecs, - mddev->bio_set); + b = bio_alloc_bioset(gfp_mask, bio->bi_max_vecs, mddev->bio_set); if (!b) return NULL; - mddevp = (void*)b; - mddevp[-1] = mddev; - b->bi_destructor = mddev_bio_destructor; + __bio_clone(b, bio); if (bio_integrity(bio)) { int ret;
@@ -5006,8 +4987,7 @@ int md_run(struct mddev *mddev) } if (mddev->bio_set == NULL) - mddev->bio_set = bioset_create(BIO_POOL_SIZE, - sizeof(struct mddev *)); + mddev->bio_set = bioset_create(BIO_POOL_SIZE, 0); spin_lock(&pers_lock); pers = find_pers(mddev->level, mddev->clevel);
diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index 76db75e..e58cd7d 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c@@ -543,14 +543,6 @@ static void iblock_complete_cmd(struct se_cmd *cmd) kfree(ibr); } -static void iblock_bio_destructor(struct bio *bio) -{ - struct se_cmd *cmd = bio->bi_private; - struct iblock_dev *ib_dev = cmd->se_dev->dev_ptr; - - bio_free(bio, ib_dev->ibd_bio_set); -} - static struct bio * iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num) {
@@ -572,7 +564,6 @@ iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num) bio->bi_bdev = ib_dev->ibd_bd; bio->bi_private = cmd; - bio->bi_destructor = iblock_bio_destructor; bio->bi_end_io = &iblock_bio_done; bio->bi_sector = lba; return bio;
diff --git a/fs/bio.c b/fs/bio.c
index 5eaa70c..86e0534 100644
--- a/fs/bio.c
+++ b/fs/bio.c@@ -271,10 +271,6 @@ EXPORT_SYMBOL(bio_init); * bio_alloc_bioset will try its own mempool to satisfy the allocation. * If %__GFP_WAIT is set then we will block on the internal pool waiting * for a &struct bio to become free. - * - * Note that the caller must set ->bi_destructor on successful return - * of a bio, to do the appropriate freeing of the bio once the reference - * count drops to zero. **/ struct bio *bio_alloc_bioset(gfp_t gfp_mask, int nr_iovecs, struct bio_set *bs) {
@@ -289,6 +285,7 @@ struct bio *bio_alloc_bioset(gfp_t gfp_mask, int nr_iovecs, struct bio_set *bs) bio = p + bs->front_pad; bio_init(bio); + bio->bi_pool = bs; if (unlikely(!nr_iovecs)) goto out_set;
@@ -315,11 +312,6 @@ err_free: } EXPORT_SYMBOL(bio_alloc_bioset); -static void bio_fs_destructor(struct bio *bio) -{ - bio_free(bio, fs_bio_set); -} - /** * bio_alloc - allocate a new bio, memory pool backed * @gfp_mask: allocation mask to use
@@ -341,12 +333,7 @@ static void bio_fs_destructor(struct bio *bio) */ struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs) { - struct bio *bio = bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set); - - if (bio) - bio->bi_destructor = bio_fs_destructor; - - return bio; + return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set); } EXPORT_SYMBOL(bio_alloc);
@@ -422,7 +409,16 @@ void bio_put(struct bio *bio) if (atomic_dec_and_test(&bio->bi_cnt)) { bio_disassociate_task(bio); bio->bi_next = NULL; - bio->bi_destructor(bio); + + /* + * This if statement is temporary - bi_pool is replacing + * bi_destructor, but bi_destructor will be taken out in another + * patch. + */ + if (bio->bi_pool) + bio_free(bio, bio->bi_pool); + else + bio->bi_destructor(bio); } } EXPORT_SYMBOL(bio_put);
@@ -473,12 +469,11 @@ EXPORT_SYMBOL(__bio_clone); */ struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask) { - struct bio *b = bio_alloc_bioset(gfp_mask, bio->bi_max_vecs, fs_bio_set); + struct bio *b = bio_alloc(gfp_mask, bio->bi_max_vecs); if (!b) return NULL; - b->bi_destructor = bio_fs_destructor; __bio_clone(b, bio); if (bio_integrity(bio)) {
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 7b7ac9c..af9dd9d 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h@@ -80,6 +80,9 @@ struct bio { struct bio_integrity_payload *bi_integrity; /* data integrity */ #endif + /* If bi_pool is non NULL, bi_destructor is not called */ + struct bio_set *bi_pool; + bio_destructor_t *bi_destructor; /* destructor */ /*
--
1.7.12