From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933327AbcLIOJd (ORCPT ); Fri, 9 Dec 2016 09:09:33 -0500 Received: from merlin.infradead.org ([205.233.59.134]:46518 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932375AbcLIOJc (ORCPT ); Fri, 9 Dec 2016 09:09:32 -0500 Date: Fri, 9 Dec 2016 15:09:13 +0100 From: Peter Zijlstra To: Hari Bathini Cc: ast@fb.com, lkml , acme@kernel.org, alexander.shishkin@linux.intel.com, mingo@redhat.com, daniel@iogearbox.net, rostedt@goodmis.org, Ananth N Mavinakayanahalli , ebiederm@xmission.com, sargun@sargun.me, Aravinda Prasad , brendan.d.gregg@gmail.com Subject: Re: [PATCH v2 1/3] perf: add PERF_RECORD_NAMESPACES to include namespaces related info Message-ID: <20161209140913.GO3107@twins.programming.kicks-ass.net> References: <147999860459.15705.11450781745380950795.stgit@hbathini.in.ibm.com> <147999864851.15705.3363371034116608966.stgit@hbathini.in.ibm.com> <20161124151011.GG3092@twins.programming.kicks-ass.net> <3d42dd8c-446d-f0de-1853-b78190a109c6@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3d42dd8c-446d-f0de-1853-b78190a109c6@linux.vnet.ibm.com> User-Agent: Mutt/1.5.23.1 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 09, 2016 at 12:10:20AM +0530, Hari Bathini wrote: > Hi Peter, > > > Sorry for taking so long to respond... > > > On Thursday 24 November 2016 08:40 PM, Peter Zijlstra wrote: > >On Thu, Nov 24, 2016 at 08:14:29PM +0530, Hari Bathini wrote: > >>@@ -862,6 +875,19 @@ enum perf_event_type { > >> */ > >> PERF_RECORD_SWITCH_CPU_WIDE = 15, > >>+ /* > >>+ * struct { > >>+ * struct perf_event_header header; > >>+ * > >>+ * u32 pid, tid; > >>+ * u64 time; > >pid,tid and time are already present in sample_id. Many of the 'legacy' > >record have redundant information since we added sample_id, but most of > >the new ones haven't and rely on sample_all being set. > > I tried using pid/tid from sample data, but realized that pid/tid in > event_id > could be different from the one in sample data, at least for fork/namespaces > events, since __perf_event_header__init_id( ) that updates the sample data > is getting the pid/tid of current task. Ah indeed. Yes please disregard my comment then.