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Date:   Mon, 25 Apr 2022 11:19:20 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc:     Christoph Hellwig <hch@lst.de>, Josef Bacik <josef@toxicpanda.com>,
        David Sterba <dsterba@suse.com>, Qu Wenruo <wqu@suse.com>,
        Naohiro Aota <naohiro.aota@wdc.com>,
        linux-btrfs@vger.kernel.org
Subject: Re: [PATCH 03/10] btrfs: split btrfs_submit_data_bio
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On Mon, Apr 25, 2022 at 05:11:15PM +0800, Qu Wenruo wrote:
>
>
> On 2022/4/25 15:54, Christoph Hellwig wrote:
>> Split btrfs_submit_data_bio into one helper for reads and one for writes.
>
> If we're splitting the bio mapping, wouldn't it be better to split by
> read/write first, then by data/meta?
>
> Especially for all read bios, we use workqueue to defer to a less strict
> context, which is unrelated to data/metadata.

Splitting the read vs write handling entirely and not allocating a
btrfs_bio for writes will be the next series after this one.  You're
getting ahead of me :)