On 07/24/2012 11:11 PM, Kent Overstreet wrote:
> 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.
>
> Signed-off-by: Kent Overstreet <koverstreet@xxxxxxxxxx>
<snip>
> diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
> index fd47950..be65582 100644
> --- a/drivers/target/target_core_iblock.c
> +++ b/drivers/target/target_core_iblock.c
> @@ -447,14 +447,6 @@ 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)
> {
> @@ -475,8 +467,15 @@ iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num)
> }
>
> bio->bi_bdev = ib_dev->ibd_bd;
> +<<<<<<< HEAD
> bio->bi_private = cmd;
> bio->bi_destructor = iblock_bio_destructor;
> +||||||| merged common ancestors
> + bio->bi_private = task;
> + bio->bi_destructor = iblock_bio_destructor;
> +=======
> + bio->bi_private = task;
> +>>>>>>> block: Generalized bio pool freeing
> bio->bi_end_io = &iblock_bio_done;
> bio->bi_sector = lba;
> return bio;
You left out a rebase merge conflict. Did you allmodconfig compile
these patches?
Boaz
> diff --git a/fs/bio.c b/fs/bio.c
> index 73922ab..1c6c8b7 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 +409,11 @@ 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);
> +
> + if (bio->bi_pool)
> + bio_free(bio, bio->bi_pool);
> + else
> + bio->bi_destructor(bio);
> }
> }
> EXPORT_SYMBOL(bio_put);
> @@ -473,12 +464,11 @@ 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 0edb65d..293547e 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 */
>
> /*
--
dm-devel mailing list
dm-devel@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/dm-devel
