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Date:   Tue, 2 Jun 2020 07:51:52 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Greg KH <gregkh@linuxfoundation.org>
Cc:     Tao pilgrim <pilgrimtao@gmail.com>, Jens Axboe <axboe@kernel.dk>,
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Subject: Re: [PATCH v2] blkdev: Replace blksize_bits() with ilog2()
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On Mon, Jun 01, 2020 at 10:44:26AM +0200, Greg KH wrote:
> But does this code path actually show up anywhere that is actually
> measurable as mattering?
> 
> If so, please show that benchmark results.

I think the requests are starting to be a bit unreasonable.  Tao is
replacing a reimplementation of a standard function with that standard
function / compiler builtin.  We don't put such a high burden on that.

And once the proper existing fields are used where possible as shown
in my reply just replacing the rest seems totally obvious - quite
contrary I think keeping a reimplementation would need a high bar.