Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757734AbcDGVwY (ORCPT ); Thu, 7 Apr 2016 17:52:24 -0400 Received: from casper.infradead.org ([85.118.1.10]:50292 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750925AbcDGVwX (ORCPT ); Thu, 7 Apr 2016 17:52:23 -0400 Date: Thu, 7 Apr 2016 18:52:13 -0300 From: Arnaldo Carvalho de Melo To: David Ahern Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Adrian Hunter , Jiri Olsa , Namhyung Kim , Wang Nan Subject: Re: [PATCH 17/19] perf tools: Build syscall table .c header from kernel's syscall_64.tbl Message-ID: <20160407215213.GD5327@redhat.com> References: <1460062720-21736-1-git-send-email-acme@kernel.org> <1460062720-21736-18-git-send-email-acme@kernel.org> <5706D604.1090508@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5706D604.1090508@gmail.com> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.5.20 (2009-12-10) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1237 Lines: 30 Em Thu, Apr 07, 2016 at 03:49:56PM -0600, David Ahern escreveu: > Upon further review ... > > On 4/7/16 2:58 PM, Arnaldo Carvalho de Melo wrote: > >From: Arnaldo Carvalho de Melo > > > >We used libaudit to map ids to syscall names and vice-versa, but that > >imposes a delay in supporting new syscalls, having to wait for libaudit > >to get those new syscalls on its tables. > > > >To remove that delay, for x86_64 initially, grab a copy of > >arch/x86/entry/syscalls/syscall_64.tbl and use it to generate those > >tables. > > > > tools/perf/Makefile.perf | 11 +- > > tools/perf/arch/x86/Makefile | 23 ++ > > tools/perf/arch/x86/entry/syscalls/syscall_64.tbl | 374 ++++++++++++++++++++++ > > tools/perf/arch/x86/entry/syscalls/syscalltbl.sh | 39 +++ > > Why make a copies of the files? Why can't perf reference the ones 2 > levels up? We did that in the past, but then, after the build broke in tools/ due to changes in the referenced files, we decided to use this "coherency protocol" where we benefit from using the kernel files but don't use it directly, being warned when changes happen so that we can do some analysis before updating our copy. - Arnaldo