[Drbd-dev] [PATCH v5 05/12] block: Kill bi_destructor
Kent Overstreet
koverstreet at google.com
Tue Aug 7 00:08:34 CEST 2012
Now that we've got generic code for freeing bios allocated from bio
pools, this isn't needed anymore.
This also changes the semantics of bio_free() a bit - it now also frees
bios allocated by bio_kmalloc(). It's also no longer exported, as
without bi_destructor there should be no need for it to be called
anywhere else.
v5: Switch to BIO_KMALLOC_POOL ((void *)~0), per Boaz
Signed-off-by: Kent Overstreet <koverstreet at google.com>
---
Documentation/block/biodoc.txt | 5 -----
block/blk-core.c | 2 +-
drivers/block/drbd/drbd_main.c | 13 +------------
fs/bio.c | 31 ++++++++++++++++---------------
include/linux/bio.h | 2 +-
include/linux/blk_types.h | 3 ---
6 files changed, 19 insertions(+), 37 deletions(-)
diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt
index e418dc0..8df5e8e 100644
--- a/Documentation/block/biodoc.txt
+++ b/Documentation/block/biodoc.txt
@@ -465,7 +465,6 @@ struct bio {
bio_end_io_t *bi_end_io; /* bi_end_io (bio) */
atomic_t bi_cnt; /* pin count: free when it hits zero */
void *bi_private;
- bio_destructor_t *bi_destructor; /* bi_destructor (bio) */
};
With this multipage bio design:
@@ -647,10 +646,6 @@ for a non-clone bio. There are the 6 pools setup for different size biovecs,
so bio_alloc(gfp_mask, nr_iovecs) will allocate a vec_list of the
given size from these slabs.
-The bi_destructor() routine takes into account the possibility of the bio
-having originated from a different source (see later discussions on
-n/w to block transfers and kvec_cb)
-
The bio_get() routine may be used to hold an extra reference on a bio prior
to i/o submission, if the bio fields are likely to be accessed after the
i/o is issued (since the bio may otherwise get freed in case i/o completion
diff --git a/block/blk-core.c b/block/blk-core.c
index 93eb3e4..e9058c2 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -2794,7 +2794,7 @@ int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
free_and_out:
if (bio)
- bio_free(bio, bs);
+ bio_free(bio);
blk_rq_unprep_clone(rq);
return -ENOMEM;
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 920ede2..19bf632 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/fs/bio.c b/fs/bio.c
index c7f3442..ebc7309 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -56,6 +56,8 @@ static struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly = {
*/
struct bio_set *fs_bio_set;
+#define BIO_KMALLOC_POOL ((void *) ~0)
+
/*
* Our slab pool management
*/
@@ -232,10 +234,21 @@ fallback:
return bvl;
}
-void bio_free(struct bio *bio, struct bio_set *bs)
+void bio_free(struct bio *bio)
{
+ struct bio_set *bs = bio->bi_pool;
void *p;
+ BUG_ON(!bs);
+
+ if (bs == BIO_KMALLOC_POOL) {
+ /* Bio was allocated by bio_kmalloc() */
+ if (bio_integrity(bio))
+ bio_integrity_free(bio, fs_bio_set);
+ kfree(bio);
+ return;
+ }
+
if (bio_has_allocated_vec(bio))
bvec_free_bs(bs, bio->bi_io_vec, BIO_POOL_IDX(bio));
@@ -346,13 +359,6 @@ struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
}
EXPORT_SYMBOL(bio_alloc);
-static void bio_kmalloc_destructor(struct bio *bio)
-{
- if (bio_integrity(bio))
- bio_integrity_free(bio, fs_bio_set);
- kfree(bio);
-}
-
/**
* bio_kmalloc - allocate a bio for I/O using kmalloc()
* @gfp_mask: the GFP_ mask given to the slab allocator
@@ -379,7 +385,7 @@ struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
bio->bi_flags |= BIO_POOL_NONE << BIO_POOL_OFFSET;
bio->bi_max_vecs = nr_iovecs;
bio->bi_io_vec = bio->bi_inline_vecs;
- bio->bi_destructor = bio_kmalloc_destructor;
+ bio->bi_pool = BIO_KMALLOC_POOL;
return bio;
}
@@ -417,12 +423,7 @@ void bio_put(struct bio *bio)
*/
if (atomic_dec_and_test(&bio->bi_cnt)) {
bio_disassociate_task(bio);
- bio->bi_next = NULL;
-
- if (bio->bi_pool)
- bio_free(bio, bio->bi_pool);
- else
- bio->bi_destructor(bio);
+ bio_free(bio);
}
}
EXPORT_SYMBOL(bio_put);
diff --git a/include/linux/bio.h b/include/linux/bio.h
index ba60319..393c87e 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -216,7 +216,7 @@ extern struct bio *bio_alloc(gfp_t, unsigned int);
extern struct bio *bio_kmalloc(gfp_t, unsigned int);
extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
extern void bio_put(struct bio *);
-extern void bio_free(struct bio *, struct bio_set *);
+extern void bio_free(struct bio *);
extern void bio_endio(struct bio *, int);
struct request_queue;
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 401c573..d10c2e49 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -84,11 +84,8 @@ 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 */
-
/*
* We can inline a number of vecs at the end of the bio, to avoid
* double allocations for a small number of bio_vecs. This member
--
1.7.7.3
More information about the drbd-dev
mailing list