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{ "id": 2215565, "url": "http://patchwork.ozlabs.org/api/covers/2215565/?format=api", "web_url": "http://patchwork.ozlabs.org/project/glibc/cover/20260324191707.3676629-1-sajan.karumanchi@amd.com/", "project": { "id": 41, "url": "http://patchwork.ozlabs.org/api/projects/41/?format=api", "name": "GNU C Library", "link_name": "glibc", "list_id": "libc-alpha.sourceware.org", "list_email": "libc-alpha@sourceware.org", "web_url": "", "scm_url": "", "webscm_url": "", "list_archive_url": "", "list_archive_url_format": "", "commit_url_format": "" }, "msgid": "<20260324191707.3676629-1-sajan.karumanchi@amd.com>", "list_archive_url": null, "date": "2026-03-24T19:17:06", "name": "[v2,0/1] x86_64: Prefer EVEX512 code-path on AMD Zen5 CPUs", "submitter": { "id": 79912, "url": "http://patchwork.ozlabs.org/api/people/79912/?format=api", "name": "Sajan Karumanchi", "email": "sajan.karumanchi@gmail.com" }, "mbox": "http://patchwork.ozlabs.org/project/glibc/cover/20260324191707.3676629-1-sajan.karumanchi@amd.com/mbox/", "series": [ { "id": 497334, "url": "http://patchwork.ozlabs.org/api/series/497334/?format=api", "web_url": "http://patchwork.ozlabs.org/project/glibc/list/?series=497334", "date": "2026-03-24T19:17:06", "name": "x86_64: Prefer EVEX512 code-path on AMD Zen5 CPUs", "version": 2, "mbox": "http://patchwork.ozlabs.org/series/497334/mbox/" } ], "comments": "http://patchwork.ozlabs.org/api/covers/2215565/comments/", "headers": { "Return-Path": "<libc-alpha-bounces~incoming=patchwork.ozlabs.org@sourceware.org>", "X-Original-To": [ "incoming@patchwork.ozlabs.org", "libc-alpha@sourceware.org" ], "Delivered-To": [ "patchwork-incoming@legolas.ozlabs.org", "libc-alpha@sourceware.org" ], "Authentication-Results": [ "legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256\n header.s=20251104 header.b=hC7gO8t1;\n\tdkim-atps=neutral", "legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org\n (client-ip=2620:52:6:3111::32; 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Simplified AVX-512 feature detection in cpu-features.c:\n2. Added tunable support in cpu-tunables.c:\n - Users can now enable/disable Prefer_EVEX512 flag at runtime\n - Syntax: GLIBC_TUNABLES=glibc.cpu.x86_cpu_features.preferred=Prefer_EVEX512\n3. More consistent with existing naming conventions in glibc codebase\n with minimal changes for maintainability.\n\nNo functional changes to the optimization logic itself - the performance\nimprovements and affected functions remain the same as v1.\n\nThank you for your review and consideration.\n\nBest regards,\nSajan Karumanchi\nAMD\n\n\nSajan Karumanchi (1):\n x86_64: Prefer EVEX512 code-path on AMD Zen5 CPUs\n\n sysdeps/x86/cpu-features.c | 8 ++++++++\n sysdeps/x86/cpu-tunables.c | 6 ++++++\n .../cpu-features-preferred_feature_index_1.def | 1 +\n sysdeps/x86_64/multiarch/ifunc-avx2.h | 15 ++++++++++++---\n sysdeps/x86_64/multiarch/ifunc-evex.h | 11 ++++++++++-\n sysdeps/x86_64/multiarch/memchr.c | 1 +\n sysdeps/x86_64/multiarch/strchr.c | 8 +++++++-\n sysdeps/x86_64/multiarch/strchrnul.c | 1 +\n sysdeps/x86_64/multiarch/strlen.c | 1 +\n sysdeps/x86_64/multiarch/strnlen.c | 1 +\n sysdeps/x86_64/multiarch/strrchr.c | 1 +\n 11 files changed, 49 insertions(+), 5 deletions(-)" }