Re: [PATCH 18/25] x86: move the XOR code to lib/raid/
From: Peter Zijlstra <peterz@infradead.org>
Date: 2026-02-28 10:31:21
Also in:
linux-alpha, linux-arch, linux-btrfs, linux-crypto, linux-raid, linux-riscv, linux-s390, linux-um, lkml, loongarch, sparclinux
On Fri, Feb 27, 2026 at 03:55:29PM -0800, Eric Biggers wrote:
On Fri, Feb 27, 2026 at 03:30:16PM +0100, Peter Zijlstra wrote:quoted
On Thu, Feb 26, 2026 at 07:10:30AM -0800, Christoph Hellwig wrote:quoted
Move the optimized XOR code out of line into lib/raid. Signed-off-by: Christoph Hellwig <hch@lst.de> --- arch/x86/include/asm/xor.h | 518 ++---------------- arch/x86/include/asm/xor_64.h | 32 -- lib/raid/xor/Makefile | 8 + .../xor_avx.h => lib/raid/xor/x86/xor-avx.c | 14 +- .../xor_32.h => lib/raid/xor/x86/xor-mmx.c | 60 +- lib/raid/xor/x86/xor-sse.c | 476 ++++++++++++++++I gotta ask, why lib/raid/xor/$arch/ instead of something like arch/$arch/lib/xor ?Similar to lib/crypto/ and lib/crc/, it allows the translation units (either .c or .S files) containing architecture-optimized XOR code to be included directly in the xor.ko module, where they should be. Previously, these were always built into the core kernel even if XOR_BLOCKS was 'n' or 'm', or they were built into a separate module xor-neon.ko which xor.ko depended on. So either the code was included unnecessarily, or there was an extra module. Technically we could instead have the lib makefile compile stuff in arch/, but that would be unusual. It's much cleaner to have the directory structure match the build system.
Hmm, I suppose. Its just weird that we now have to look in both arch/$foo and lib/*/$foo/ to find all arch code. And I don't suppose symlinks would make it better?