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From:   Christoph Hellwig <hch@lst.de>
To:     Greg KH <gregkh@linuxfoundation.org>
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Subject: Re: [PATCH v2] blkdev: Replace blksize_bits() with ilog2()
Message-ID: <20200602055152.GA11620@lst.de>
References: <20200529141100.37519-1-pilgrimtao@gmail.com> <c8412d98-0328-0976-e5f9-5beddc148a35@kernel.dk> <CAAWJmAZOQQQeNiTr48OSRRdO2pG+q4c=6gjT55CkWC5FN=HXmA@mail.gmail.com> <20200601084426.GB1667318@kroah.com>
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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.