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=-21.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL 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 00DF7C282C2 for ; Thu, 7 Feb 2019 22:02:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BFD2921721 for ; Thu, 7 Feb 2019 22:02:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="hT0sOTj7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727191AbfBGWCz (ORCPT ); Thu, 7 Feb 2019 17:02:55 -0500 Received: from mail-qk1-f201.google.com ([209.85.222.201]:43184 "EHLO mail-qk1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727174AbfBGWCy (ORCPT ); Thu, 7 Feb 2019 17:02:54 -0500 Received: by mail-qk1-f201.google.com with SMTP id z126so1388603qka.10 for ; Thu, 07 Feb 2019 14:02:53 -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=o+AJ8QXrg2DBnZGy5ZK6HlHEP2OPjBoRWVCrnuFEEho=; b=hT0sOTj7b3PLD8UwlhjluEWCgaUqFcwBupSFo+rIsarXYKEEWRH8u5FdyH7Xyl9LMI BzEnQsTHoKZJRQxb6hXGp7lQh0jmZm3p0FYgvxRFytFo6ty1cwfFm3I+I4L4j+PNQH3a gz33UvMVgKqYwpyW7oeYb8bcxcbe+sOBeFgWf5nnPwdONZq/izCL3HqA4tP4mhgnqGAq se5QlTXVg+Jfy5sonuqLJR4zqRK768Pt6ayAIESLzTLDpKkHDCxl1BGzCjwCOHsVcQfN RR8BQfIeBGdlTq30stNQ0Oi8PfTYdErpUaW/zDoFT+nFtJGLGkHwP73oPrd4SRZzqhLI dKWg== 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=o+AJ8QXrg2DBnZGy5ZK6HlHEP2OPjBoRWVCrnuFEEho=; b=qstcMYN0NtGEHUTffHYmohaPqcgZntJPo8T755339nlkMsC5WrpXJJWy7Pba8xf7rp HKkyV+p1IN/vrNKqM2a5klX64Re17YeN8UIWK1tYlBCrlnabTAdN/hGiTtLoVPnuvgr2 W+gJsQbZsAt1JG40o2mHTQdqU6jtTm4laX9OgxR9p/2uFG6YBV6pBmu2kdZZb3fWwCUe 0Qd3izQSCH7+m0qZDoa7hDkWiPgjYu7/ZnOwudR+56zCwqz5gSmY+if++BfZfunu9CZp IUl0FvdYv7cd8CNsZJaLMY7pYNyouT+c6YMdmagouROq/xkh0q01FBIScgZhdsbYM20T 2iPw== X-Gm-Message-State: AHQUAuZfljyP4f15rkaFB7UP9Np6DWGxorw+Bw1z6FXKrHUIZISYxa05 5rNsZmeGR6WE8d5xPi8Nc4lSZHmSzzou2+N3iJw= X-Google-Smtp-Source: AHgI3IZpSTvveps4gw9Ymi9LhC8L0aj58ECu2QXXZgpry+dP6rog7BE3nXSvtl0Om6ewMCVDLY3yy1gx+yqMFm/NSvc= X-Received: by 2002:a0c:b0b6:: with SMTP id o51mr10787701qvc.40.1549576972858; Thu, 07 Feb 2019 14:02:52 -0800 (PST) Date: Thu, 7 Feb 2019 14:01:52 -0800 In-Reply-To: <20190207220155.81351-1-ndesaulniers@google.com> Message-Id: <20190207220155.81351-4-ndesaulniers@google.com> Mime-Version: 1.0 References: <20190207220155.81351-1-ndesaulniers@google.com> X-Mailer: git-send-email 2.20.1.791.gb4d0f1c61a-goog Subject: [PATCH 4/4] Makefile: lld: set -O2 linker flag when linking with LLD From: ndesaulniers@google.com To: yamada.masahiro@socionext.com Cc: Nick Desaulniers , Rui Ueyama , Nathan Chancellor , Michal Marek , linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org 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 -O2 enables tail merging of string table strings. For arm64: 0.34% size improvement with lld -O2 over lld for vmlinux. 3.30% 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 Signed-off-by: Nick Desaulniers --- Makefile | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/Makefile b/Makefile index 6307c17259ea..c07208ec49d4 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 -- 2.20.1.791.gb4d0f1c61a-goog