From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753713AbbLILJj (ORCPT ); Wed, 9 Dec 2015 06:09:39 -0500 Received: from mx1.redhat.com ([209.132.183.28]:50727 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751436AbbLILJi (ORCPT ); Wed, 9 Dec 2015 06:09:38 -0500 Subject: Re: [Questions] perf c2c: What's the current status of perf c2c? To: Peter Zijlstra , Jiri Olsa References: <5667A8D4.4090601@huawei.com> <20151209080440.GA17211@krava.brq.redhat.com> <20151209093402.GM6356@twins.programming.kicks-ass.net> Cc: Yunlong Song , dzickus@redhat.com, dsahern@gmail.com, fweisbec@gmail.com, efault@gmx.de, paulus@samba.org, rfowles@redhat.com, eranian@google.com, "acme@kernel.org >> Arnaldo Carvalho de Melo" , mingo@redhat.com, Linux Kernel Mailing List , Jiri Olsa , "wangnan0@huawei.com >> Wang Nan" , fowles@inreach.com, Namhyung Kim , andi@firstfloor.org From: Joe Mario Message-ID: <56680BEF.7090502@redhat.com> Date: Wed, 9 Dec 2015 06:09:35 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 MIME-Version: 1.0 In-Reply-To: <20151209093402.GM6356@twins.programming.kicks-ass.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [RESEND - this time w/o html junk] On 12/09/2015 04:34 AM, Peter Zijlstra wrote: > On Wed, Dec 09, 2015 at 09:04:40AM +0100, Jiri Olsa wrote: >> On Wed, Dec 09, 2015 at 12:06:44PM +0800, Yunlong Song wrote: >>> Hi, Don, >>> I am interested in the perf c2c tool, which is introduced in: http://lwn.net/Articles/588866/ >>> However, I found that this tool has not been applied to the mainline tree of perf, Why? It was first >>> introduced in Feb. 2014. What's its current status now? Does it have a new version or a repository >>> somewhere else? And does it support Haswell? >> >> hi, >> not sure Don made any progress on this field, but I'm having >> his c2c sources rebased current perf sources ATM. >> > So I never really liked the c2c tool because it was so narrowly > focussed, it only works on NUMA thingies IIRC. > > I would much rather see a tool that uses PEBS events and does a dwarf > decode of the exact instruction's data reference -- without relying on > data address bits. Peter: Yes, that would be a great enhancement, but is it any reason to hold up the current implementation? I've been using "perf c2c" heavily with customers over the past two years and after they see what it can do, their first question is why it hasn't been checked in upstream yet. Joe