From patchwork Fri Jun 18 23:30:23 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nick Desaulniers X-Patchwork-Id: 12332411 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6784DC48BE8 for ; Fri, 18 Jun 2021 23:30:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 506AE613C1 for ; Fri, 18 Jun 2021 23:30:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234838AbhFRXdB (ORCPT ); Fri, 18 Jun 2021 19:33:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234647AbhFRXdA (ORCPT ); Fri, 18 Jun 2021 19:33:00 -0400 Received: from mail-qk1-x74a.google.com (mail-qk1-x74a.google.com [IPv6:2607:f8b0:4864:20::74a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D0C42C061760 for ; Fri, 18 Jun 2021 16:30:49 -0700 (PDT) Received: by mail-qk1-x74a.google.com with SMTP id t144-20020a3746960000b02903ad9c5e94baso6996839qka.16 for ; Fri, 18 Jun 2021 16:30:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=K5IKvJejgNpA3AFkHBDCXpqjsqKJvtxs1XINxFL+/80=; b=Xv1vHb+6WsCa/m6Vu4jkUgfv1Vfd65hhIYj1E3ovZR0PeSnobLEZ8/fkUe0eW4cw9K yDZ7kCLjXQ7qoo6HDD6UtUX371UzqR+Ln4OgvkHTaIzVLvh8NPmG67ec4obfZhhR9D1r wG/Zpu1orD+4NmfnjCqPZjGf9nOuo0lVIUYkhbYV6FPjdHnZmHKd3veFeTf14H4CGmlv v/PwyJLYCw7Xq/GwW4fgY8vwlddErA6HThDqWuFyK9CR8Y83dz1jVNtwk+2vNcDVJV1U pQu2txUobp7XJW2tyungb03WIolNt1xZvhhD5A+rWy5p/xWtqYE38+HOv9Xf/4asOGv3 KIDQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=K5IKvJejgNpA3AFkHBDCXpqjsqKJvtxs1XINxFL+/80=; b=piT0r5vKE2JenLFfvQgCuyrJh7AF3URpmfebsCFpRV7ROrEhWYVvhU89G7mh2Ck4li ODOo3wOppRIWASa4BxTpZlkRu+QBl5zO1wFW13rpg6iHJd0cfp6/Mh50fSxezQL6wIQ3 HM6zPL5OiWq/gSLqELEFqLVuZAUio5F9czCylVw9i4XrjVKT2jDpygx7+08CQS4FnOvz Ro+QCfPxHs/esrke9BNUvCMwuICNZFIsiltwwpoXbv13vifrUcgUwx2dkD997f6TBqmq 4aITEHVJ4TryuYzwueCgKQr2gEpTJTczyIBrMH+2mvl3M9KhbP6ogM6rsi0A08oEdwj5 A3gA== X-Gm-Message-State: AOAM532D1OD9rBprjhIVLJ2+8aY1bpY7mdiSkxJdSRusbzR89QeAUXI3 NCG8XQ+fVckcWiHjaL86kFyYPHrRNLVlCctAcHk= X-Google-Smtp-Source: ABdhPJzv3iuu4rmC8ir3YJzvMzMIGBJAAJJhBB51vid/gVjQPP1e/24XhYkWkAPDbTnLwPxLy7jP+XAcFn4lE+v0wXI= X-Received: from ndesaulniers1.mtv.corp.google.com ([2620:15c:211:202:7c41:e84c:8fcb:6664]) (user=ndesaulniers job=sendgmr) by 2002:a25:d257:: with SMTP id j84mr16278281ybg.404.1624059048916; Fri, 18 Jun 2021 16:30:48 -0700 (PDT) Date: Fri, 18 Jun 2021 16:30:23 -0700 In-Reply-To: <20210618233023.1360185-1-ndesaulniers@google.com> Message-Id: <20210618233023.1360185-3-ndesaulniers@google.com> Mime-Version: 1.0 References: <20210618233023.1360185-1-ndesaulniers@google.com> X-Mailer: git-send-email 2.32.0.288.g62a8d224e6-goog Subject: [PATCH 2/2] Kconfig: CC_HAS_NO_PROFILE_FN_ATTR, depend on for GCOV and PGO From: Nick Desaulniers To: Kees Cook Cc: Peter Zijlstra , Bill Wendling , Sami Tolvanen , Peter Oberparleiter , Masahiro Yamada , Miguel Ojeda , Nathan Chancellor , Luc Van Oostenryck , Ard Biesheuvel , Will Deacon , Arnd Bergmann , Andrew Morton , Rasmus Villemoes , linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, x86@kernel.org, Borislav Petkov , Martin Liska , Marco Elver , Jonathan Corbet , Fangrui Song , linux-doc@vger.kernel.org, linux-kbuild@vger.kernel.org, Dmitry Vyukov , johannes.berg@intel.com, linux-toolchains@vger.kernel.org, Nick Desaulniers Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org We don't want compiler instrumentation to touch noinstr functions, which are annotated with the no_profile function attribute. Add a Kconfig test for this and make PGO and GCOV depend on it. Cc: Masahiro Yamada Cc: Peter Oberparleiter Link: https://lore.kernel.org/lkml/YMTn9yjuemKFLbws@hirez.programming.kicks-ass.net/ Link: https://lore.kernel.org/lkml/YMcssV%2Fn5IBGv4f0@hirez.programming.kicks-ass.net/ Suggested-by: Peter Zijlstra Signed-off-by: Nick Desaulniers --- init/Kconfig | 3 +++ kernel/gcov/Kconfig | 1 + kernel/pgo/Kconfig | 3 ++- 3 files changed, 6 insertions(+), 1 deletion(-) diff --git a/init/Kconfig b/init/Kconfig index 1ea12c64e4c9..540f862b40c6 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -83,6 +83,9 @@ config TOOLS_SUPPORT_RELR config CC_HAS_ASM_INLINE def_bool $(success,echo 'void foo(void) { asm inline (""); }' | $(CC) -x c - -c -o /dev/null) +config CC_HAS_NO_PROFILE_FN_ATTR + def_bool $(success,echo '__attribute__((no_profile)) int x();' | $(CC) -x c - -c -o /dev/null -Werror) + config CONSTRUCTORS bool diff --git a/kernel/gcov/Kconfig b/kernel/gcov/Kconfig index 58f87a3092f3..19facd4289cd 100644 --- a/kernel/gcov/Kconfig +++ b/kernel/gcov/Kconfig @@ -5,6 +5,7 @@ config GCOV_KERNEL bool "Enable gcov-based kernel profiling" depends on DEBUG_FS depends on !CC_IS_CLANG || CLANG_VERSION >= 110000 + depends on !X86 || (X86 && CC_HAS_NO_PROFILE_FN_ATTR) select CONSTRUCTORS default n help diff --git a/kernel/pgo/Kconfig b/kernel/pgo/Kconfig index d2053df1111c..26f75ac4c6c1 100644 --- a/kernel/pgo/Kconfig +++ b/kernel/pgo/Kconfig @@ -8,7 +8,8 @@ config PGO_CLANG bool "Enable clang's PGO-based kernel profiling" depends on DEBUG_FS depends on ARCH_SUPPORTS_PGO_CLANG - depends on CC_IS_CLANG && CLANG_VERSION >= 120000 + depends on CC_IS_CLANG + depends on CC_HAS_NO_PROFILE_FN_ATTR help This option enables clang's PGO (Profile Guided Optimization) based code profiling to better optimize the kernel.