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Date:   Thu, 16 Jun 2022 08:36:18 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc:     Christoph Hellwig <hch@lst.de>, David Sterba <dsterba@suse.com>,
        Josef Bacik <josef@toxicpanda.com>, Qu Wenruo <wqu@suse.com>,
        linux-btrfs@vger.kernel.org
Subject: Re: [PATCH 4/5] btrfs: remove the raid56_parity_{write,recover}
 return value
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On Thu, Jun 16, 2022 at 09:06:50AM +0800, Qu Wenruo wrote:
>> But at this branch, we don't yet have called
>> `btrfs_bio_counter_inc_noblocked()`.
>>
>> Wouldn't this cause underflow?
>>

>>>       rbio->operation = BTRFS_RBIO_WRITE;
>>>       rbio_add_bio(rbio, bio);
>>>
>>> -    btrfs_bio_counter_inc_noblocked(fs_info);
>
> And this line is removed completely, any reason for the removal?

This is all part of making these functions consume the bio counter
as documented in the changelog.  But I guess splitting that from
the pure prototype change should help to able to understand the
changes, so I'll do that for the next version.