From patchwork Mon Jun 27 18:28:26 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rabin Vincent X-Patchwork-Id: 9201089 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 70392607D3 for ; Mon, 27 Jun 2016 18:28:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 672022859F for ; Mon, 27 Jun 2016 18:28:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5BF50285AB; Mon, 27 Jun 2016 18:28:56 +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=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID 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 9644A2859F for ; Mon, 27 Jun 2016 18:28:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751906AbcF0S2y (ORCPT ); Mon, 27 Jun 2016 14:28:54 -0400 Received: from mail-wm0-f68.google.com ([74.125.82.68]:33101 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751891AbcF0S2y (ORCPT ); Mon, 27 Jun 2016 14:28:54 -0400 Received: by mail-wm0-f68.google.com with SMTP id r201so27022841wme.0; Mon, 27 Jun 2016 11:28:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id; bh=FBSFcZNNQgC957moim4GeAqVroDK41ClnHkEvvGmxGo=; b=R2kE0oZW683+gi9cGPZ6DMEzPHD1uF0LM5OrNxSxjGeFKLkmVymKaiqH39tbnU5wzI QLEedKRHQ0SHWfmTU9kb6sr6r/cOhZjB+6rQPiuOGqqHVhol5HQ7If1Xy/FKl0MdqBdF 3QjuJ574rcK+Lnfg0I2NPtCLb352FiwX+sivenLwEUGsicXHiYljWgTZ1mNUnJLRFI9u KkQN8SApVUj64ewkGwsM7UGlz1wu8kvTpL9QOMtjAgHpPRuMkfB+M/llNe45JE7kRVGq dshN9seNp6y6pxRh3x6gXRZ6cbHz+CovZWTLl8shM+LDuPU6I6SI2Jb8Dw+vLspnpyj1 JYqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id; bh=FBSFcZNNQgC957moim4GeAqVroDK41ClnHkEvvGmxGo=; b=aGgM49rutvKFxNITCMOaiLp5T0bscEV7E6YS8tbYpXTpe29yDkMb4Givvfp2HYH8+l VXOQr3P7Sdv+n3EE5EmGxkBAnemah04Pb7ZYebI1Jm8JG/5XZ5/1/EtEuGq8u+ChVK0z Y7xa+wkDFqdJFisuOZ2UjT7eIYl0Ec9GocqNFB6itUe0jmVAjnIqYwACML5A+BzpmcYl o9RfC4Uikeg09ACL34tAEDjjlpFwnoWqpefd94D6Ao09KZU2JWkSHefdZs06zrfx6aZH IugsnZriID+U+k124efMp7CVjtkT6W/ZziuBLihcFqG3BWJIh75otTy2RWea3SvZ7yJ/ Yjdw== X-Gm-Message-State: ALyK8tLQ4bdJFAfoE1nq/GSxHYEC4wv8a5BhuGEVUzHmwyvgX+D8UlZdo9J7EtraizP1zw== X-Received: by 10.194.79.228 with SMTP id m4mr2066938wjx.171.1467052132275; Mon, 27 Jun 2016 11:28:52 -0700 (PDT) Received: from localhost.localdomain (90-231-144-194-no56.tbcn.telia.com. [90.231.144.194]) by smtp.gmail.com with ESMTPSA id q69sm226848wmd.4.2016.06.27.11.28.51 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 27 Jun 2016 11:28:51 -0700 (PDT) From: Rabin Vincent To: mmarek@suse.com Cc: linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, Rabin Vincent Subject: [PATCH 1/2] Makefile: evaluate LDFLAGS_BUILD_ID only once Date: Mon, 27 Jun 2016 20:28:26 +0200 Message-Id: <1467052107-26735-1-git-send-email-rabin@rab.in> X-Mailer: git-send-email 2.8.1 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 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 on my machine: $ make -j8 && perf stat -r5 make -j8 Before: 1,086617617 seconds time elapsed ( +- 0,37% ) After: 0,864487173 seconds time elapsed ( +- 0,35% ) Signed-off-by: Rabin Vincent --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Makefile b/Makefile index 6471f20ca400..91baa282f3fa 100644 --- a/Makefile +++ b/Makefile @@ -814,7 +814,7 @@ KBUILD_AFLAGS += $(ARCH_AFLAGS) $(KAFLAGS) KBUILD_CFLAGS += $(ARCH_CFLAGS) $(KCFLAGS) # Use --build-id when available. -LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\ +LDFLAGS_BUILD_ID := $(patsubst -Wl$(comma)%,%,\ $(call cc-ldoption, -Wl$(comma)--build-id,)) KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID) LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)