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[73.224.175.84]) by smtp.gmail.com with ESMTPSA id 00721157ae682-6fd3ca41e81sm16218887b3.29.2025.03.02.07.47.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 02 Mar 2025 07:47:43 -0800 (PST) Date: Sun, 2 Mar 2025 10:47:41 -0500 From: Yury Norov To: David Laight Cc: Kuan-Wei Chiu , tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, jk@ozlabs.org, joel@jms.id.au, eajames@linux.ibm.com, andrzej.hajda@intel.com, neil.armstrong@linaro.org, rfoss@kernel.org, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, airlied@gmail.com, simona@ffwll.ch, dmitry.torokhov@gmail.com, mchehab@kernel.org, awalls@md.metrocast.net, hverkuil@xs4all.nl, miquel.raynal@bootlin.com, richard@nod.at, vigneshr@ti.com, louis.peens@corigine.com, andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, pabeni@redhat.com, parthiban.veerasooran@microchip.com, arend.vanspriel@broadcom.com, johannes@sipsolutions.net, gregkh@linuxfoundation.org, jirislaby@kernel.org, akpm@linux-foundation.org, hpa@zytor.com, alistair@popple.id.au, linux@rasmusvillemoes.dk, Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@gmail.com, kuba@kernel.org, linux-kernel@vger.kernel.org, linux-fsi@lists.ozlabs.org, dri-devel@lists.freedesktop.org, linux-input@vger.kernel.org, linux-media@vger.kernel.org, linux-mtd@lists.infradead.org, oss-drivers@corigine.com, netdev@vger.kernel.org, linux-wireless@vger.kernel.org, brcm80211@lists.linux.dev, brcm80211-dev-list.pdl@broadcom.com, linux-serial@vger.kernel.org, bpf@vger.kernel.org, jserv@ccns.ncku.edu.tw, Yu-Chun Lin Subject: Re: [PATCH 02/17] bitops: Add generic parity calculation for u64 Message-ID: References: <20250223164217.2139331-1-visitorckw@gmail.com> <20250223164217.2139331-3-visitorckw@gmail.com> <20250226222911.22cb0c18@pumpkin> <20250227215741.1c2e382f@pumpkin> Precedence: bulk X-Mailing-List: linux-input@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250227215741.1c2e382f@pumpkin> 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