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Date:   Wed, 26 Oct 2022 10:34:35 -0600
From:   Keith Busch <kbusch@kernel.org>
To:     Bart Van Assche <bvanassche@acm.org>
Cc:     Dawei Li <set_pte_at@outlook.com>, axboe@kernel.dk, hch@lst.de,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] block: simplify blksize_bits() implementation
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On Wed, Oct 26, 2022 at 09:29:21AM -0700, Bart Van Assche wrote:
> On 10/26/22 08:14, Dawei Li wrote:
> > Convert current looping-based implementation into bit operation,
> > which can bring improvement for:
> > 
> > 1) bitops is more efficient for its arch-level optimization.
> 
> As far as I know blksize_bits() is not used in the hot path so performance
> of this function is not critical.

blksize_bits() is used on every IO going through iomap_dio_bio_iter(),
though the usage there is completely unnecessary and can be removed.