From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751461AbdECEts (ORCPT ); Wed, 3 May 2017 00:49:48 -0400 Received: from conssluserg-04.nifty.com ([210.131.2.83]:65499 "EHLO conssluserg-04.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751010AbdECEtk (ORCPT ); Wed, 3 May 2017 00:49:40 -0400 DKIM-Filter: OpenDKIM Filter v2.10.3 conssluserg-04.nifty.com v434nU7U030312 X-Nifty-SrcIP: [209.85.213.171] MIME-Version: 1.0 In-Reply-To: <20170430161600.15845-1-rabin@rab.in> References: <20170430161600.15845-1-rabin@rab.in> From: Masahiro Yamada Date: Wed, 3 May 2017 13:49:29 +0900 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] Makefile: evaluate LDFLAGS_BUILD_ID only once To: Rabin Vincent Cc: Michal Marek , Linux Kbuild mailing list , Linux Kernel Mailing List Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2017-05-01 1:16 GMT+09:00 Rabin Vincent : > Evaluate LDFLAGS_BUILD_ID (which involves invoking the compiler) only > once instead of over and over. > > This provides a ~20% reduction in null build time with x86 allnoconfig: > > $ make allnoconfig && make -j8 > $ perf stat -r5 -e sched:sched_process_exec make -j8 > - 2 119 sched:sched_process_exec > + 1 878 sched:sched_process_exec > > - 1,238817018 seconds time elapsed > + 0,971020553 seconds time elapsed > > Signed-off-by: Rabin Vincent Applied to linux-kbuild/kbuild. Thanks! -- Best Regards Masahiro Yamada