From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnaldo Carvalho de Melo Subject: Re: [PATCH 1/2] perf report: ensure the perf DSO mapping matches what libdw sees Date: Fri, 2 Jun 2017 16:49:10 -0300 Message-ID: <20170602194910.GB31764@kernel.org> References: <20170602143753.16907-1-milian.wolff@kdab.com> <20170602152341.GB7901@redhat.com> <13986004.8uJxbMKobt@agathebauer> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail.kernel.org ([198.145.29.99]:57838 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750966AbdFBTtO (ORCPT ); Fri, 2 Jun 2017 15:49:14 -0400 Content-Disposition: inline In-Reply-To: <13986004.8uJxbMKobt@agathebauer> Sender: linux-perf-users-owner@vger.kernel.org List-ID: To: Milian Wolff Cc: Arnaldo Carvalho de Melo , Linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Namhyung Kim , Jiri Olsa Em Fri, Jun 02, 2017 at 06:21:44PM +0200, Milian Wolff escreveu: > On Freitag, 2. Juni 2017 17:23:41 CEST Arnaldo Carvalho de Melo wrote: > > Looks ok, having both implementations matching and the callchains making > > sense for your workloads is a good way to verify the sanity, thanks. > > I wonder if we shouldn't somehow script this, i.e. build it with one > > implementation, generate output from some test workload, build it with > > the other, second output, diff it, report when not the same. > That does sound like a good idea, but I'm unsure how to do it. Note that many > "simple" tests work just fine. Only larger complicated workloads trigger this > issue for me. > One potential way to test it would be `perf archive` - i.e. I send you the > binaries involved and then we can use perf script diffing to ensure it all > works... Humm, I'm trying to cook up a: perf data filter --pid 12345 --perf-data-offset 1234567 --output perf.data.subset to allow when finding some case like that to get a small subset of a perf.data file with just the sample we want to get the backtrace from + the mmaps, etc up to that point. With that I could keep a repo of interesting perf.data files to have in my regression tests. - Arnaldo