Re: [PATCH] btrfs: Remove pair of bio_get/put in btrfs_schedule_bio

[Liu Bo <bo.li.liu@oracle.com>]

On Mon, Dec 11, 2017 at 04:38:48PM +0200, Nikolay Borisov wrote:
> This code was added in 492bb6deee34 ("Btrfs: Hold a reference on bios
> during submit_bio, add some extra bio checks"). However, holding a
> reference on a bio is necessary only if it's going to be referenced
> after the submit_bio returns and the bio is completed. In this
> particular instance this is not the case so there is no need to hold
> an extra reference since we directly return.
>

Looks good.  If possible, please also drop other unnecessary bio_get()
in btrfs.

Reviewed-by: Liu Bo <bo.li.liu@oracle.com>

-liubo
> Signed-off-by: Nikolay Borisov <nborisov@suse.com>
> ---
>  fs/btrfs/volumes.c | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
> index 49810b70afd3..13827ff648ec 100644
> --- a/fs/btrfs/volumes.c
> +++ b/fs/btrfs/volumes.c
> @@ -6069,9 +6069,7 @@ static noinline void btrfs_schedule_bio(struct btrfs_device *device,
>  
>  	/* don't bother with additional async steps for reads, right now */
>  	if (bio_op(bio) == REQ_OP_READ) {
> -		bio_get(bio);
>  		btrfsic_submit_bio(bio);
> -		bio_put(bio);
>  		return;
>  	}
>  
> -- 
> 2.7.4
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html