On 22.11.18 г. 18:16 ч., David Sterba wrote:
> The end_io callback implemented as btrfs_io_bio_endio_readpage only
> calls kfree. Also the callback is set only in case the csum buffer is
> allocated and not pointing to the inline buffer. We can use that
> information to drop the indirection and call a helper that will free the
> csums only in the right case.
>
> This shrinks struct btrfs_io_bio by 8 bytes.
>
> Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Reviewed-by: Nikolay Borisov <nborisov@xxxxxxxx>
> ---
> fs/btrfs/extent_io.c | 3 +--
> fs/btrfs/file-item.c | 9 ---------
> fs/btrfs/inode.c | 7 ++-----
> fs/btrfs/volumes.h | 10 ++++++++--
> 4 files changed, 11 insertions(+), 18 deletions(-)
>
> diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
> index 4ea808d6cfbc..aef3c9866ff0 100644
> --- a/fs/btrfs/extent_io.c
> +++ b/fs/btrfs/extent_io.c
> @@ -2623,8 +2623,7 @@ static void end_bio_extent_readpage(struct bio *bio)
> if (extent_len)
> endio_readpage_release_extent(tree, extent_start, extent_len,
> uptodate);
> - if (io_bio->end_io)
> - io_bio->end_io(io_bio, blk_status_to_errno(bio->bi_status));
> + btrfs_io_bio_free_csum(io_bio);
> bio_put(bio);
> }
>
> diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
> index 1f2d0a6ab634..920bf3b4b0ef 100644
> --- a/fs/btrfs/file-item.c
> +++ b/fs/btrfs/file-item.c
> @@ -142,14 +142,6 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
> return ret;
> }
>
> -static void btrfs_io_bio_endio_readpage(struct btrfs_io_bio *bio, int err)
> -{
> - if (bio->csum != bio->csum_inline) {
> - kfree(bio->csum);
> - bio->csum = NULL;
> - }
> -}
> -
> static blk_status_t __btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio,
> u64 logical_offset, u32 *dst, int dio)
> {
> @@ -184,7 +176,6 @@ static blk_status_t __btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio
> btrfs_free_path(path);
> return BLK_STS_RESOURCE;
> }
> - btrfs_bio->end_io = btrfs_io_bio_endio_readpage;
> } else {
> btrfs_bio->csum = btrfs_bio->csum_inline;
> }
> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> index 26b8bec7c2dc..6bfd37e58924 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -8017,9 +8017,7 @@ static void btrfs_endio_direct_read(struct bio *bio)
>
> dio_bio->bi_status = err;
> dio_end_io(dio_bio);
> -
> - if (io_bio->end_io)
> - io_bio->end_io(io_bio, blk_status_to_errno(err));
> + btrfs_io_bio_free_csum(io_bio);
> bio_put(bio);
> }
>
> @@ -8372,8 +8370,7 @@ static void btrfs_submit_direct(struct bio *dio_bio, struct inode *inode,
> if (!ret)
> return;
>
> - if (io_bio->end_io)
> - io_bio->end_io(io_bio, ret);
> + btrfs_io_bio_free_csum(io_bio);
>
> free_ordered:
> /*
> diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
> index 9a764f2d462e..a13045fcfc45 100644
> --- a/fs/btrfs/volumes.h
> +++ b/fs/btrfs/volumes.h
> @@ -267,14 +267,12 @@ struct btrfs_fs_devices {
> * we allocate are actually btrfs_io_bios. We'll cram as much of
> * struct btrfs_bio as we can into this over time.
> */
> -typedef void (btrfs_io_bio_end_io_t) (struct btrfs_io_bio *bio, int err);
> struct btrfs_io_bio {
> unsigned int mirror_num;
> unsigned int stripe_index;
> u64 logical;
> u8 *csum;
> u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
> - btrfs_io_bio_end_io_t *end_io;
> struct bvec_iter iter;
> /*
> * This member must come last, bio_alloc_bioset will allocate enough
> @@ -288,6 +286,14 @@ static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
> return container_of(bio, struct btrfs_io_bio, bio);
> }
>
> +static inline void btrfs_io_bio_free_csum(struct btrfs_io_bio *io_bio)
> +{
> + if (io_bio->csum != io_bio->csum_inline) {
> + kfree(io_bio->csum);
> + io_bio->csum = NULL;
> + }
> +}
> +
> struct btrfs_bio_stripe {
> struct btrfs_device *dev;
> u64 physical;
>
