From mboxrd@z Thu Jan 1 00:00:00 1970 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=-12.8 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 52103C2D0E4 for ; Thu, 3 Sep 2020 20:38:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3110A20684 for ; Thu, 3 Sep 2020 20:38:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=google.com header.i=@google.com header.b="d3WTta76" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729329AbgICUiM (ORCPT ); Thu, 3 Sep 2020 16:38:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35484 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729522AbgICUcE (ORCPT ); Thu, 3 Sep 2020 16:32:04 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 083DAC061265 for ; Thu, 3 Sep 2020 13:31:20 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id a5so4011838ybh.3 for ; Thu, 03 Sep 2020 13:31:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=v4aEDtr6bLZLPmR/ra6D5NVXgPqHTR+q2+p+53rP8YU=; b=d3WTta769MJh+Bo0VzFx1dIubRn1F3/0OsgdvpRIABs/0F8aoQ0QxN6GC6ogiN8YAt 1n2fy7ycG6neE8i4JP6mcoL5+gOWppxCnH2U8kbhGmk3Ke0U/7qP7lute7a6H0uDoYhQ dWVIqp9Xjw2Q1WEklB8eqrGPTTy0VYDaAb7Vj5vkDxGtzwmgFWOj15UwJBAbJ05tl1sN Q4rZl0DzGVRAuAw5PJyrACjWBxr1NbGCE0oN5TR+pUi+Dq3TH5paoF63RYX5l7QEOrpB +a+BflxQgXchm/xsTBNIInkXUZW2NMgvFiHC7w8tScjlytwkaK3yal7TbaDvFzX+VZKt 2LRg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=v4aEDtr6bLZLPmR/ra6D5NVXgPqHTR+q2+p+53rP8YU=; b=eKr0pKxk8kbhW4fDl6/pfpSIie3Dw081SftsrphRqAUbSBRRUM+eFNTVtELIjyNhOr nvTl1oNMh4Rjr9eSL8msSEyP271OKqAvowBnuaV4bFJ3hpN8gWVzwqjcpVo8i3VSssXO wrqWCZUuiGYj1ilbvnHRiCdCgohN5cSXtSpLgV5HtDYcaMIK0B3kNlaycP/gOL3ZmCwu Jb0afcMOlcbp5t3Cu/dowPWXgueCtu+P7o5zTupsnIcz9L+Nj4CFrEnOqdwh5E1I8hhK gt9PYe6cLSR6hAlXG8+QhGt11t0MQP9b9v3IYfuJDXPIVmXVZbENu9sqfwahl+QQsZ2k Kjxg== X-Gm-Message-State: AOAM530tm5xUuflZFXb6Ct/7rZvvFWTsk55pMDVdbf36kTC1neUn1E3i vzCerzUfQQvQ4h5G1hB9e70SehjZtgfOKOHIUWQ= X-Google-Smtp-Source: ABdhPJxLcteMiXx6yxIAtF7C6LDsd43v+S+v/BljrbTvv0EuuMtNnvGzhvJa2qGTBh5Tw0uOlOWuvZqeImKd2fr7SwI= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a25:a366:: with SMTP id d93mr5081717ybi.415.1599165079173; Thu, 03 Sep 2020 13:31:19 -0700 (PDT) Date: Thu, 3 Sep 2020 13:30:37 -0700 In-Reply-To: <20200903203053.3411268-1-samitolvanen@google.com> Message-Id: <20200903203053.3411268-13-samitolvanen@google.com> Mime-Version: 1.0 References: <20200624203200.78870-1-samitolvanen@google.com> <20200903203053.3411268-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.526.ge36021eeef-goog Subject: [PATCH v2 12/28] kbuild: lto: limit inlining From: Sami Tolvanen To: Masahiro Yamada , Will Deacon Cc: Peter Zijlstra , Steven Rostedt , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This change limits function inlining across translation unit boundaries in order to reduce the binary size with LTO. The -import-instr-limit flag defines a size limit, as the number of LLVM IR instructions, for importing functions from other TUs, defaulting to 100. Based on testing with arm64 defconfig, we found that a limit of 5 is a reasonable compromise between performance and binary size, reducing the size of a stripped vmlinux by 11%. Suggested-by: George Burgess IV Signed-off-by: Sami Tolvanen --- Makefile | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/Makefile b/Makefile index 2752be67b460..c69e07bd506a 100644 --- a/Makefile +++ b/Makefile @@ -917,6 +917,10 @@ else CC_FLAGS_LTO_CLANG := -flto endif CC_FLAGS_LTO_CLANG += -fvisibility=default + +# Limit inlining across translation units to reduce binary size +LD_FLAGS_LTO_CLANG := -mllvm -import-instr-limit=5 +KBUILD_LDFLAGS += $(LD_FLAGS_LTO_CLANG) endif ifdef CONFIG_LTO -- 2.28.0.402.g5ffc5be6b7-goog From mboxrd@z Thu Jan 1 00:00:00 1970 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=-12.8 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 B3DF5C2D0E1 for ; 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Thu, 03 Sep 2020 13:31:19 -0700 (PDT) Date: Thu, 3 Sep 2020 13:30:37 -0700 In-Reply-To: <20200903203053.3411268-1-samitolvanen@google.com> Message-Id: <20200903203053.3411268-13-samitolvanen@google.com> Mime-Version: 1.0 References: <20200624203200.78870-1-samitolvanen@google.com> <20200903203053.3411268-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.526.ge36021eeef-goog Subject: [PATCH v2 12/28] kbuild: lto: limit inlining From: Sami Tolvanen To: Masahiro Yamada , Will Deacon X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200903_213123_680873_E9B255CD X-CRM114-Status: GOOD ( 12.70 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, x86@kernel.org, Kees Cook , "Paul E. McKenney" , kernel-hardening@lists.openwall.com, Peter Zijlstra , Greg Kroah-Hartman , linux-kbuild@vger.kernel.org, Nick Desaulniers , linux-kernel@vger.kernel.org, Steven Rostedt , clang-built-linux@googlegroups.com, Sami Tolvanen , linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org This change limits function inlining across translation unit boundaries in order to reduce the binary size with LTO. The -import-instr-limit flag defines a size limit, as the number of LLVM IR instructions, for importing functions from other TUs, defaulting to 100. Based on testing with arm64 defconfig, we found that a limit of 5 is a reasonable compromise between performance and binary size, reducing the size of a stripped vmlinux by 11%. Suggested-by: George Burgess IV Signed-off-by: Sami Tolvanen --- Makefile | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/Makefile b/Makefile index 2752be67b460..c69e07bd506a 100644 --- a/Makefile +++ b/Makefile @@ -917,6 +917,10 @@ else CC_FLAGS_LTO_CLANG := -flto endif CC_FLAGS_LTO_CLANG += -fvisibility=default + +# Limit inlining across translation units to reduce binary size +LD_FLAGS_LTO_CLANG := -mllvm -import-instr-limit=5 +KBUILD_LDFLAGS += $(LD_FLAGS_LTO_CLANG) endif ifdef CONFIG_LTO -- 2.28.0.402.g5ffc5be6b7-goog _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel From mboxrd@z Thu Jan 1 00:00:00 1970 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=-12.8 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 12E78C2D0A6 for ; Thu, 3 Sep 2020 20:33:33 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 6C268208C7 for ; Thu, 3 Sep 2020 20:33:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="d3WTta76" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6C268208C7 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-19731-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 21810 invoked by uid 550); 3 Sep 2020 20:31:31 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 21724 invoked from network); 3 Sep 2020 20:31:30 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=v4aEDtr6bLZLPmR/ra6D5NVXgPqHTR+q2+p+53rP8YU=; b=d3WTta769MJh+Bo0VzFx1dIubRn1F3/0OsgdvpRIABs/0F8aoQ0QxN6GC6ogiN8YAt 1n2fy7ycG6neE8i4JP6mcoL5+gOWppxCnH2U8kbhGmk3Ke0U/7qP7lute7a6H0uDoYhQ dWVIqp9Xjw2Q1WEklB8eqrGPTTy0VYDaAb7Vj5vkDxGtzwmgFWOj15UwJBAbJ05tl1sN Q4rZl0DzGVRAuAw5PJyrACjWBxr1NbGCE0oN5TR+pUi+Dq3TH5paoF63RYX5l7QEOrpB +a+BflxQgXchm/xsTBNIInkXUZW2NMgvFiHC7w8tScjlytwkaK3yal7TbaDvFzX+VZKt 2LRg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=v4aEDtr6bLZLPmR/ra6D5NVXgPqHTR+q2+p+53rP8YU=; b=ZDrmgiPyijVA+h2G/75YxbkiGqOAKV69CwpsmOLqpzJ0s/N3uXiAFKsWtZsrdwaaxd Ixcckl5aTLV0qPLH4ctUWpgG1OPbRzbUJjxJNp6gMMZRQskYwuh7HkvhcEwG5J9hzifo V879hW4Yur9ugaAKcTFEWUgNmRaEC/lWmCZe+I1btUeXVmx4CdOLu2KSk7gp6VsJe6Qo QBRiLtdOS4zkWidhKNVLG0GBB+cFtWOHgyzU91DfcC3cxGb8y0wPUPCnvRIi8PIrrFeL my9Gm9mLfpBodR4HrBysMqb72GB9u040E0ethzIXc2WVmju2w4mbvPipPPR3xVpwv0Yj nEuA== X-Gm-Message-State: AOAM532FCJSSh/4LaTnjRZQi69MRs6+HJF0IbrBBjzZ5AI0rMtAdpDLP IXmeWJSoirpy3wsyPvTm489PNnpaTxLV/W2P+R0= X-Google-Smtp-Source: ABdhPJxLcteMiXx6yxIAtF7C6LDsd43v+S+v/BljrbTvv0EuuMtNnvGzhvJa2qGTBh5Tw0uOlOWuvZqeImKd2fr7SwI= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a25:a366:: with SMTP id d93mr5081717ybi.415.1599165079173; Thu, 03 Sep 2020 13:31:19 -0700 (PDT) Date: Thu, 3 Sep 2020 13:30:37 -0700 In-Reply-To: <20200903203053.3411268-1-samitolvanen@google.com> Message-Id: <20200903203053.3411268-13-samitolvanen@google.com> Mime-Version: 1.0 References: <20200624203200.78870-1-samitolvanen@google.com> <20200903203053.3411268-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.526.ge36021eeef-goog Subject: [PATCH v2 12/28] kbuild: lto: limit inlining From: Sami Tolvanen To: Masahiro Yamada , Will Deacon Cc: Peter Zijlstra , Steven Rostedt , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen Content-Type: text/plain; charset="UTF-8" This change limits function inlining across translation unit boundaries in order to reduce the binary size with LTO. The -import-instr-limit flag defines a size limit, as the number of LLVM IR instructions, for importing functions from other TUs, defaulting to 100. Based on testing with arm64 defconfig, we found that a limit of 5 is a reasonable compromise between performance and binary size, reducing the size of a stripped vmlinux by 11%. Suggested-by: George Burgess IV Signed-off-by: Sami Tolvanen --- Makefile | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/Makefile b/Makefile index 2752be67b460..c69e07bd506a 100644 --- a/Makefile +++ b/Makefile @@ -917,6 +917,10 @@ else CC_FLAGS_LTO_CLANG := -flto endif CC_FLAGS_LTO_CLANG += -fvisibility=default + +# Limit inlining across translation units to reduce binary size +LD_FLAGS_LTO_CLANG := -mllvm -import-instr-limit=5 +KBUILD_LDFLAGS += $(LD_FLAGS_LTO_CLANG) endif ifdef CONFIG_LTO -- 2.28.0.402.g5ffc5be6b7-goog