From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian Hunter Subject: Re: [PATCH 11/16] perf intel-pt: Add support for synthesizing callchains for regular events Date: Fri, 17 Apr 2020 16:50:00 +0300 Message-ID: <5b8f28f5-968f-bfff-68af-ed0350a90765@intel.com> References: <20200401101613.6201-1-adrian.hunter@intel.com> <20200401101613.6201-12-adrian.hunter@intel.com> <20200416151443.GA2650@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20200416151443.GA2650@kernel.org> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Arnaldo Carvalho de Melo Cc: Jiri Olsa , Andi Kleen , linux-kernel@vger.kernel.org, Namhyung Kim , linux-perf-users@vger.kernel.org List-Id: linux-perf-users.vger.kernel.org On 16/04/20 6:14 pm, Arnaldo Carvalho de Melo wrote: > Em Wed, Apr 01, 2020 at 01:16:08PM +0300, Adrian Hunter escreveu: >> Currently, callchains can be synthesized only for synthesized events. >> Support also synthesizing callchains for regular events. > > This is super cool, I wonder if we shouldn't do it automatically or just > adding a new type of callchains, i.e.: > > perf record --call-graph pt uname > > Should take care of all the details, i.e. do the extra steps below > behind the scenes. > > Possibly even find out that the workload specified was built with > -fomit-frame-pointers, that the hardware has Intel PT and do all behind > the scenes for: > > perf record -g uname > > Alternatively we could take some less seemingly far fetched approach and > make this configurable via: > > perf config call-graph.record-mode=pt > > What do you think? Adding a --call-graph option sounds reasonable, and config to define default callgraph options. But this was done at Andi Kleen's request, so he may want to comment.