Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752150Ab3HUPXO (ORCPT ); Wed, 21 Aug 2013 11:23:14 -0400 Received: from merlin.infradead.org ([205.233.59.134]:59683 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751574Ab3HUPXN (ORCPT ); Wed, 21 Aug 2013 11:23:13 -0400 Date: Wed, 21 Aug 2013 17:23:05 +0200 From: Peter Zijlstra To: Steven Rostedt Cc: Jiejing Zhang , Frederic Weisbecker , Ingo Molnar , linux-kernel@vger.kernel.org, Eric Miao , Jiejing Zhang Subject: Re: [PATCH] ftrace: add tgid information in task switch event. Message-ID: <20130821152305.GD31370@twins.programming.kicks-ass.net> References: <1377097520-24898-1-git-send-email-jasozhang@nvidia.com> <20130821110944.32bdf03a@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130821110944.32bdf03a@gandalf.local.home> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1209 Lines: 30 On Wed, Aug 21, 2013 at 11:09:44AM -0400, Steven Rostedt wrote: > > From: Jiejing Zhang > > > > ftrace only report pid in task switch event, which is > > actually thread ID in user space view, the comm of > > the thread will be like "Thread-1", "Compiler", etc > > in android system, it's useful if we can add tgid > > information in ftrace event to find out the process > > id, and the process id's comm will help us to figure > > out the application, which was useful on data analysis > > tools. Meh.. are you telling me you really can't do that otherwise? Adding this information makes the tracepoint slower for everybody else. How about you enable trace_sched_process_fork() and track things that way? Also, last time I tried to change one of these stupid tracepoints userspace broke.. Rostedt says people should be using libtraceevent but I'm sceptical. > > Change-Id: Ia99f58a56d691d770b3beb2f76de0351e6194a4a That needs to die. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/