From patchwork Thu Jun 1 14:57:07 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 100939 Delivered-To: patch@linaro.org Received: by 10.140.96.100 with SMTP id j91csp845672qge; Thu, 1 Jun 2017 07:58:07 -0700 (PDT) X-Received: by 10.36.28.139 with SMTP id c133mr14903746itc.117.1496329087841; Thu, 01 Jun 2017 07:58:07 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1496329087; cv=none; d=google.com; s=arc-20160816; b=Y4FNUeti/STghY4XqgpXOGYejlopi1Z2aOPK/SlwDDvxaq/j2RRi15JxmkA1g+V+6d lH6TpIzARmKmNS2V0jC8F6lj3aZn4k5o9tVz3nosM6Bpq7LKrUg1WzhbsrEEdRJUbBu1 0vtADb/m4NzFLUWk6Q46IG4lt31i6LFPxGgRdiXkv0GnXN3GVTcPY78gN2qV9y8zZ68S 1dgFMclR5g/A26W3Y6W8IaYwHxJXFEIYtUDuhOHga6L3xqwbEvCO8KD+oFP+IYCkC/dN 1tdhyfJwM6RVMc9g42RCU37X9VINbGTu39YPyr1EHRNcPLHcc46lisqYJATauPCQW8oz tc2Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:message-id:date:subject:cc:to:from :arc-authentication-results; bh=OcxKR0rqoUSX3n1bAx7f9x1DZIiX8s3SF4bWn6zumRU=; b=QXbml5yA0WID7g1VkOMGfvFeoWx42SW0nMlmH05USCdnya5vbzQfsZpQdDdGsPLCr5 0+cGAa/w536w4niKQQ9ILZZfMNqXobD0yxQKUY+nzVxuvAjR73fplRvn24VadHcy2zWr O/DqF5rG+JrSirX1Upv4i867SWxna/WWu+L23pCvCSN8Bo+u/Y1Ow/CPhkwlTxbIYjAz xvIP4dmB0WL5MdSYqrK4Mo7YZDqBBmxTcxLzeWUKBNr0MegU4tW78KWIgux6GqEN6kSm tAbjLdj4/nPEzRaBH6HBI2zvpnoScxIfDNUrG0GzaTw4N6y2kA/hAZCbtjDwbM35J6OS lMQg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id t17si20925088itb.44.2017.06.01.07.58.07; Thu, 01 Jun 2017 07:58:07 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751417AbdFAO5y (ORCPT + 25 others); Thu, 1 Jun 2017 10:57:54 -0400 Received: from mout.kundenserver.de ([212.227.126.133]:49489 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751266AbdFAO5w (ORCPT ); Thu, 1 Jun 2017 10:57:52 -0400 Received: from wuerfel.lan ([78.42.17.5]) by mrelayeu.kundenserver.de (mreue003 [212.227.15.129]) with ESMTPA (Nemesis) id 0MQaxF-1dSqWW12E9-00Tz27; Thu, 01 Jun 2017 16:57:17 +0200 From: Arnd Bergmann To: Masahiro Yamada Cc: Michal Marek , linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, sam@ravnborg.org, Arnd Bergmann Subject: [PATCH] kbuild: speed up checksyscalls.sh Date: Thu, 1 Jun 2017 16:57:07 +0200 Message-Id: <20170601145707.590629-1-arnd@arndb.de> X-Mailer: git-send-email 2.9.0 X-Provags-ID: V03:K0:gUny4YpkV2ZwjCSy0u3V93pW/WPoVLTzQq8HLPUSsHyV9yN4Lgj cFi00OzAQCFnOnYXgleHAtE4KAd8m/4RgBlv8Hd90rD2jXBhcaojUsaqUojKYh2ReFyXZhk M9hMjslQg6uXqgz9I1z+8dUFfbo++SaeovLwjJ6F8mNagRR//pqymGpDoxAGEiDbw5Aa0cV 60cAF89HAbVA7/NKCQMgg== X-UI-Out-Filterresults: notjunk:1; V01:K0:5e5ZnDmMZDA=:cSJQct7MWKpz/QYFX9wfWW XQG1jFxlaK7A+30LLA5Ho4er5ePssy7LcR77ewIptF7GqrI9Gi+i2QGGL5n+M0zYs48JuU8J0 RCzd5ISxzbtvVx2ByTn+iybA9/YRmQuk6W2OpmndoIX+JR+0EJQoR16cDzYk93As5kGVv6s43 5As/dpuoWKnT1FOqN8w/V2AtWB2KKmQ3JO6CUG+/BkpsM4WNXbfsy6YR5EMHjEE8PAtQcfHxu g14kOTGTpjk3RwlZSis/EfjoBMEzdtqFCaOQSwS4AZYcNc9lUiWtzYRWhtmlJ35lE5sZURDSs o2OPhLNT6cpBJodmL68D3Nibqj9pRPCFhpPFxZvvnJfORrtPpp6RUItaDPc7/grFzxyehlswG FeMusJOP9W7s9jt10rZEtQ1hp3wVy1G+a2Ub4jBuGYBYjmOy3o76XIKXAAtTs/1Q0mGCNAqhd hcr7bJGfIUFEhtB1bMedM5EdapkkG8fJEdhUsF1w2dbVt+VOcIpe9mJI5gaDeypV/L0VwF0fZ 7SHcMgFudjKnqbkwOtkAYmb7G0a83Tj8LWyflMLcNSQzpcDoaNLJiVPwOuMWpB/YNk8dI1y6c k5gn7TaeGPITL6jcO9yX/xrflEnb7l0KLtxxqkE9Wz7dZhesVGsfrMJV7rhejOPAR/paOl8v7 GrXilYioNX2ST/bHB9nGtOp5LdMnZ1g+aEMWSKODO5lyb99BzYvpBWmkqxaEgTFZynzs= Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org checksyscalls.sh is run at every "make" run while building the kernel, even if no files have changed. I looked at where we spend time in a trivial empty rebuild and found checksyscalls.sh to be a source of noticeable overhead, as it spawns a lot of child processes just to call 'cat' copying from stdin to stdout, once for each of the over 400 x86 syscalls. Using a shell-builtin (echo) instead of the external command gives us a 13x speedup: Before After real 0m1.018s real 0m0.077s user 0m0.068s user 0m0.048s sys 0m0.156s sys 0m0.024s The time it took to rebuild a single file on my machine dropped from 5.5 seconds to 4.5 seconds. Signed-off-by: Arnd Bergmann --- scripts/checksyscalls.sh | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) -- 2.9.0 diff --git a/scripts/checksyscalls.sh b/scripts/checksyscalls.sh index 0cce56da3706..b8c9d2b04ffc 100755 --- a/scripts/checksyscalls.sh +++ b/scripts/checksyscalls.sh @@ -231,15 +231,12 @@ EOF } syscall_list() { - grep '^[0-9]' "$1" | sort -n | ( + grep '^[0-9]' "$1" | sort -n | while read nr abi name entry ; do - cat <