From patchwork Mon Dec 6 03:23:03 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "H.J. Lu" X-Patchwork-Id: 48522 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 04968385840D for ; Mon, 6 Dec 2021 03:23:29 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 04968385840D DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1638761009; bh=ixL3y7QbGgc35bW3eNv/1WpBCkq+TjUJH1H3kxLjj1E=; h=To:Subject:Date:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:From; b=qD4AYHnzC7NqZeav4ErFBkXCDiHRIK81rcFCV4rz/eWA1+O1etZKbwa0botCnGPjt efu73OX3DN3KDq4K+nMRQvNYnNI78twK9DJg1AJkJJQhJyoCBcceNiIJibTkexm0GE EDm1q91TLAMTOkszfFDcMla+jMP9V0FqvE0g078w= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail-pl1-x62e.google.com (mail-pl1-x62e.google.com [IPv6:2607:f8b0:4864:20::62e]) by sourceware.org (Postfix) with ESMTPS id 51A3C3858D28 for ; Mon, 6 Dec 2021 03:23:06 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 51A3C3858D28 Received: by mail-pl1-x62e.google.com with SMTP id u11so6187356plf.3 for ; Sun, 05 Dec 2021 19:23:06 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:subject:date:message-id:mime-version :content-transfer-encoding; bh=ixL3y7QbGgc35bW3eNv/1WpBCkq+TjUJH1H3kxLjj1E=; b=pPt/2w0y/XY0W5DYCBpKuvUdehbeXzx2/VADx9hhFZcselEbOYVb0Fcbw/e+N3dZT1 +Bzkd+qCAGFHpJLxjxo+REusQlzA5ZgGkgCiDCO4plgqVLIsmCFRCzRr1OWDsYSSsWyR yKEDsqD9DF2NHo2bJ0PoU/qWBPDWPrYqiXAH9hPz9RR7pIE7yNGnmnfEbSu01Wzuc0zi zh7VKSZ8SGmj5xHzqudJ/ul0nuYGiE9qyoSurQm6G+t7SBeFcHKZW4ZzoU19/1TopD4D XphRofKxtWD4fHOLQprX42gKVsjKzL+qtls7PTMIc8/jeC8ZSEWWGC9cWkf5FJ3It0th zkmA== X-Gm-Message-State: AOAM533DerGQSMFvhd1ZtEy0m8n/eS7L/BelqEWlyFLZNzsbP+hR8Jik zfIrja8lvYD9oLFMcLxADNMqAYbcFsY= X-Google-Smtp-Source: ABdhPJx9rN0J1CYu49Q/bsc0NIJ+saUBo9CVpTqX3MUtXujSZT9iuLkNEoPVgriCAvVPegAvVr++2w== X-Received: by 2002:a17:90a:6bc2:: with SMTP id w60mr33968420pjj.88.1638760985323; Sun, 05 Dec 2021 19:23:05 -0800 (PST) Received: from gnu-cfl-2.localdomain ([172.58.35.133]) by smtp.gmail.com with ESMTPSA id y6sm10867230pfi.154.2021.12.05.19.23.05 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 05 Dec 2021 19:23:05 -0800 (PST) Received: from gnu-cfl-2.. (localhost [IPv6:::1]) by gnu-cfl-2.localdomain (Postfix) with ESMTP id 0AE7C1A00E1 for ; Sun, 5 Dec 2021 19:23:04 -0800 (PST) To: libc-alpha@sourceware.org Subject: [PATCH] x86: Don't set Prefer_No_AVX512 for processors with AVX512 and AVX-VNNI Date: Sun, 5 Dec 2021 19:23:03 -0800 Message-Id: <20211206032303.7159-1-hjl.tools@gmail.com> X-Mailer: git-send-email 2.33.1 MIME-Version: 1.0 X-Spam-Status: No, score=-3029.5 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_FROM, GIT_PATCH_0, RCVD_IN_BARRACUDACENTRAL, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: "H.J. Lu via Libc-alpha" From: "H.J. Lu" Reply-To: "H.J. Lu" Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" Don't set Prefer_No_AVX512 on processors with AVX512 and AVX-VNNI since they won't lower CPU frequency when ZMM load and store instructions are used. --- sysdeps/x86/cpu-features.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c index be2498b2e7..311ade1f26 100644 --- a/sysdeps/x86/cpu-features.c +++ b/sysdeps/x86/cpu-features.c @@ -538,8 +538,11 @@ init_cpu_features (struct cpu_features *cpu_features) |= bit_arch_Prefer_No_VZEROUPPER; else { - cpu_features->preferred[index_arch_Prefer_No_AVX512] - |= bit_arch_Prefer_No_AVX512; + /* Processors with AVX512 and AVX-VNNI won't lower CPU frequency + when ZMM load and store instructions are used. */ + if (!CPU_FEATURES_CPU_P (cpu_features, AVX_VNNI)) + cpu_features->preferred[index_arch_Prefer_No_AVX512] + |= bit_arch_Prefer_No_AVX512; /* Avoid RTM abort triggered by VZEROUPPER inside a transactionally executing RTM region. */