Re: [PATCH v11 19/40] btrfs: extract page adding function

From: Josef Bacik <josef@toxicpanda.com>
To: Naohiro Aota <naohiro.aota@wdc.com>,
	linux-btrfs@vger.kernel.org, dsterba@suse.com
Cc: hare@suse.com, linux-fsdevel@vger.kernel.org,
	Jens Axboe <axboe@kernel.dk>,
	Christoph Hellwig <hch@infradead.org>,
	"Darrick J. Wong" <darrick.wong@oracle.com>
Subject: Re: [PATCH v11 19/40] btrfs: extract page adding function
Date: Mon, 11 Jan 2021 11:22:34 -0500	[thread overview]
Message-ID: <429b0dc8-d02e-40e1-6d86-ad3788c3beba@toxicpanda.com> (raw)
In-Reply-To: <a442f64e5fd84a823993e81f81f29287cd4ec274.1608608848.git.naohiro.aota@wdc.com>

On 12/21/20 10:49 PM, Naohiro Aota wrote:
> This commit extract page adding to bio part from submit_extent_page(). The
> page is added only when bio_flags are the same, contiguous and the added
> page fits in the same stripe as pages in the bio.
> 
> Condition checkings are reordered to allow early return to avoid possibly
> heavy btrfs_bio_fits_in_stripe() calling.
> 
> Reviewed-by: Josef Bacik <josef@toxicpanda.com>
> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
> ---
>   fs/btrfs/extent_io.c | 56 ++++++++++++++++++++++++++++++++------------
>   1 file changed, 41 insertions(+), 15 deletions(-)
> 
> diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
> index 129d571a5c1a..2f070a9e5b22 100644
> --- a/fs/btrfs/extent_io.c
> +++ b/fs/btrfs/extent_io.c
> @@ -3061,6 +3061,44 @@ struct bio *btrfs_bio_clone_partial(struct bio *orig, int offset, int size)
>   	return bio;
>   }
>   
> +/**
> + * btrfs_bio_add_page	-	attempt to add a page to bio
> + * @bio:	destination bio
> + * @page:	page to add to the bio
> + * @logical:	offset of the new bio or to check whether we are adding
> + *              a contiguous page to the previous one
> + * @pg_offset:	starting offset in the page
> + * @size:	portion of page that we want to write
> + * @prev_bio_flags:  flags of previous bio to see if we can merge the current one
> + * @bio_flags:	flags of the current bio to see if we can merge them

Just a nit, you're missing @return here, the commit flags caught this, I'd 
recommend adding our commit flags to your local repo so you can preemptively 
catch these sort of things

https://github.com/btrfs/btrfs-workflow/blob/master/patch-submission.md

under the "Git config options" section.  If you have to respin you can add it 
then.  Thanks,

Josef