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Subject: Re: [PATCH 1/1] blk-mq: reuse code in blk_mq_check_inflight*()
To:     Christoph Hellwig <hch@infradead.org>
Cc:     Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <11ebb046bf422facf6e438672799306b80038173.1569830385.git.asml.silence@gmail.com>
 <20190930083324.GA24152@infradead.org>
From:   Pavel Begunkov <asml.silence@gmail.com>
Message-ID: <97498865-bb36-7367-4cf3-de6d812b23cb@gmail.com>
Date:   Mon, 30 Sep 2019 12:20:18 +0300
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On 9/30/2019 11:33 AM, Christoph Hellwig wrote:
> On Mon, Sep 30, 2019 at 11:27:32AM +0300, Pavel Begunkov (Silence) wrote:
>> From: Pavel Begunkov <asml.silence@gmail.com>
>>
>> 1. Reuse the same walker callback for both blk_mq_in_flight() and
>> blk_mq_in_flight_rw().
>>
>> 2. Store inflight counters immediately in struct mq_inflight.
>> It's type-safer and removes extra indirection.
> 
> You really want to split this into two patches.  Part 2 looks very

Good point, diff is peculiarly aligned indeed. I will resend it.

> sensible to me, but I don't really see how 1 is qn equivalent
> transformation right now.  Splitting it out and writing a non-trivial
> changelog might help understanding it if you think it really is
> equivalent as-is.
> 

blk_mq_check_inflight() increments only inflight[0].
blk_mq_check_inflight_rw() increments inflight[0] or inflight[1]
depending on a flag, so summing them gives what the first function returns.

-- 
Yours sincerely,
Pavel Begunkov