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Miller" , Andreas Larsson , Richard Weinberger , Anton Ivanov , Johannes Berg , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Herbert Xu , Dan Williams , Chris Mason , David Sterba , Arnd Bergmann , Song Liu , Yu Kuai , Li Nan , linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, loongarch@lists.linux.dev, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, linux-crypto@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-arch@vger.kernel.org, linux-raid@vger.kernel.org Subject: Re: cleanup the RAID5 XOR library Message-Id: <20260226102037.b855483efa0bf23c72d130d3@linux-foundation.org> In-Reply-To: <20260226151106.144735-1-hch@lst.de> References: <20260226151106.144735-1-hch@lst.de> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Thu, 26 Feb 2026 07:10:12 -0800 Christoph Hellwig wrote: > the XOR library used for the RAID5 parity is a bit of a mess right now. > The main file sits in crypto/ despite not being cryptography and not > using the crypto API, with the generic implementations sitting in > include/asm-generic and the arch implementations sitting in an asm/ > header in theory. The latter doesn't work for many cases, so > architectures often build the code directly into the core kernel, or > create another module for the architecture code. > > Changes this to a single module in lib/ that also contains the > architecture optimizations, similar to the library work Eric Biggers > has done for the CRC and crypto libraries later. After that it changes > to better calling conventions that allow for smarter architecture > implementations (although none is contained here yet), and uses > static_call to avoid indirection function call overhead. Thanks, I'll add this to mm.git's mm-nonmm-unstable tree for some testing in linux-next.