linux-kernel - Re: [PATCH 02/17] bitops: Add generic parity calculation for u64

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Message-ID: <Z8R9nQmfeVvfDiOn@thinkpad>
Date: Sun, 2 Mar 2025 10:47:41 -0500
From: Yury Norov <yury.norov@...il.com>
To: David Laight <david.laight.linux@...il.com>
Cc: Kuan-Wei Chiu <visitorckw@...il.com>, tglx@...utronix.de,
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	Yu-Chun Lin <eleanor15x@...il.com>
Subject: Re: [PATCH 02/17] bitops: Add generic parity calculation for u64

On Thu, Feb 27, 2025 at 09:57:41PM +0000, David Laight wrote:
> > It's still unclear to me that this parity thing is used in hot paths.
> > If that holds, it's unclear that your hand-made version is better than
> > what's generated by GCC.
> 
> I wasn't seriously considering doing that optimisation.
> Perhaps just hoping is might make a compiler person think :-)

David, can you suggest only things you're seriously considered to do?
Random suggestions distract my contributors and make them doing unneeded
work and experiments.

In the other thread you asked I Hsin to try your approach to GENMASK()
macro, saying you're lazy. I don't think this is the right way to
communicate, not mentioning that if you're lazy to try your own
approach, it doesn't sound nice to ask someone else to try it.

Thanks for understanding,
Yury