From patchwork Mon Feb 11 19:30:06 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nick Desaulniers X-Patchwork-Id: 10806729 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B811F6C2 for ; Mon, 11 Feb 2019 19:31:01 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A73DE2B093 for ; Mon, 11 Feb 2019 19:31:01 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9AD4C2B0A8; Mon, 11 Feb 2019 19:31:01 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, USER_IN_DEF_DKIM_WL autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4F74E2B093 for ; Mon, 11 Feb 2019 19:31:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388295AbfBKTat (ORCPT ); Mon, 11 Feb 2019 14:30:49 -0500 Received: from mail-qk1-f201.google.com ([209.85.222.201]:43771 "EHLO mail-qk1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388289AbfBKTat (ORCPT ); Mon, 11 Feb 2019 14:30:49 -0500 Received: by mail-qk1-f201.google.com with SMTP id a11so2119358qkk.10 for ; Mon, 11 Feb 2019 11:30:48 -0800 (PST) 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=fgo15CY3NgYRpF97TzDUfVV2bSFDYAqgksNtaJxXuEA=; b=P33ZEVn9lWw4ExXF0pVb2kRhsMzsHIZnSCIoTjgHA67m1TBvJkvTccmmchHplJnzYi tK2h0WoALbgU2nZkZBJ2SxgLYpjlLfwsyM0qPDqW+WBGaVbVrCsDmIH6NfN+z6JfOa8G T+CWOFyTf+3H6TpEGTUvVR3EWZKAFrVXa/1HeoxRLcFre021WqnSEaB0okT2cdrUH/Zp j6/LfS6vWUOX8eAWpEshZ9EdhfKAPlTBxfbG9fyzxahFURQCfQqWoyJvynTy4bLNZmAd Fru81lvlu6FIits75GNMSWZETZYzfa/xtYGwkz6eLWKT5EO6vuFx7ZpACi8+YI0l12y3 10LQ== 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=fgo15CY3NgYRpF97TzDUfVV2bSFDYAqgksNtaJxXuEA=; b=XLe5o26ZchfqSkFFA2KORkLVcCvlQYpVsT4e1GaLpiDumVEPbTRHj4H5meJvaD42Rw WM+AlH0dDMht5wUBV6P0ZE46afbZxxbb0cebGz1fPkWfDtLLenIOP1RRg2udi6YyCHEQ OGlvb3wrqievU8fn/OskOFU0PgDpIn94Wi6QCnYaj8LVa1+d1EWzau/NLs+5pRV7jEAY t7SfJ7Vs9jMkNrM/SoiK9YCxFcSkyfSSh0x0rbu1EKmWuW/lxgnw6MHFedbqcWEeyJNm Lg5GxzAQpdtfEu0jQb3OMAhMNyN8Vz3vWyJetwFB6QgktBhJJZO31sk/O3bA9y5e+Pdj eyHA== X-Gm-Message-State: AHQUAubcQltc/JrFy658eyh64wqMaKy4BNeTqv7DGCpNYBMf3hoQT3pN xiovifUiCCnvViKCUtR50RdLuULYIrfc9scKO9c= X-Google-Smtp-Source: AHgI3IY6emNTamoLiOwa6pdZ0u5LLMBlSN9RZx8mrz70CAMQpxHxS0uzBm81DdK35Kw3x7EGXJpyDAJvrnUO/HSEvdc= X-Received: by 2002:a0c:add8:: with SMTP id x24mr21936434qvc.16.1549913448304; Mon, 11 Feb 2019 11:30:48 -0800 (PST) Date: Mon, 11 Feb 2019 11:30:06 -0800 In-Reply-To: <20190211193008.24101-1-ndesaulniers@google.com> Message-Id: <20190211193008.24101-4-ndesaulniers@google.com> Mime-Version: 1.0 References: <20190211193008.24101-1-ndesaulniers@google.com> X-Mailer: git-send-email 2.20.1.791.gb4d0f1c61a-goog Subject: [PATCH v2 4/4] Makefile: lld: set -O2 linker flag when linking with LLD From: ndesaulniers@google.com To: yamada.masahiro@socionext.com Cc: natechancellor@gmail.com, sedat.dilek@gmail.com, keescook@chromium.org, samitolvanen@google.com, michal.lkml@markovi.net, akpm@linux-foundation.org, hannes@cmpxchg.org, peterz@infradead.org, linux@dominikbrodowski.net, npiggin@gmail.com, mathieu.desnoyers@efficios.com, gor@linux.ibm.com, adrian@lisas.de, rgb@redhat.com, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, Nick Desaulniers , Rui Ueyama Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP For arm64: 0.34% size improvement with lld -O2 over lld for vmlinux. 3.3% size improvement with lld -O2 over lld for Image.lz4-dtb. Link: https://github.com/ClangBuiltLinux/linux/issues/343 Suggested-by: Rui Ueyama Suggested-by: Nathan Chancellor Reviewed-by: Nathan Chancellor Tested-by: Nathan Chancellor Signed-off-by: Nick Desaulniers --- Changes V1->V2: * add tested and reviewed by tags. Makefile | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/Makefile b/Makefile index 00e8e01d23fc..8011555745aa 100644 --- a/Makefile +++ b/Makefile @@ -718,6 +718,10 @@ else KBUILD_CFLAGS += -Wno-unused-but-set-variable endif +ifdef CONFIG_LD_IS_LLD +KBUILD_LDFLAGS += -O2 +endif + KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable) ifdef CONFIG_FRAME_POINTER KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls