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[82.69.66.36]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4804dbbb3c4sm16602415e9.13.2026.01.23.02.16.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 23 Jan 2026 02:16:08 -0800 (PST) Date: Fri, 23 Jan 2026 10:16:02 +0000 From: David Laight To: Feng Jiang Cc: Andy Shevchenko , Andy Shevchenko , pjw@kernel.org, palmer@dabbelt.com, aou@eecs.berkeley.edu, alex@ghiti.fr, akpm@linux-foundation.org, kees@kernel.org, andy@kernel.org, ebiggers@kernel.org, martin.petersen@oracle.com, ardb@kernel.org, charlie@rivosinc.com, conor.dooley@microchip.com, ajones@ventanamicro.com, linus.walleij@linaro.org, nathan@kernel.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH v3 0/8] riscv: optimize string functions and add kunit tests Message-ID: <20260123101602.111c6210@pumpkin> In-Reply-To: <26d08954-2826-4c48-a540-6e0857faf5ec@kylinos.cn> References: <20260120065852.166857-1-jiangfeng@kylinos.cn> <691a0183-6f41-4956-82da-abb69a449919@kylinos.cn> <20260121105717.04853c5d@pumpkin> <26d08954-2826-4c48-a540-6e0857faf5ec@kylinos.cn> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; arm-unknown-linux-gnueabihf) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Fri, 23 Jan 2026 11:12:00 +0800 Feng Jiang wrote: >... > I am still exploring some of the finer points of these low-level performance > trade-offs, so your input is very helpful. I will definitely spend some time > studying this further and experiment with the approaches you mentioned. You can spend a long time micro-optimising small functions. I know, I've done it.... Then you need to test on as many cpu variants as you can find. David