Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933298AbbFJGvv (ORCPT ); Wed, 10 Jun 2015 02:51:51 -0400 Received: from mail-wi0-f182.google.com ([209.85.212.182]:36227 "EHLO mail-wi0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751431AbbFJGvo (ORCPT ); Wed, 10 Jun 2015 02:51:44 -0400 Date: Wed, 10 Jun 2015 08:51:39 +0200 From: Ingo Molnar To: Steven Rostedt Cc: Vince Weaver , David Ahern , linux-kernel@vger.kernel.org, Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Stephane Eranian , Jiri Olsa , Arnaldo Carvalho de Melo Subject: Re: perf/ftrace: does PERF_EVENT_IOC_SET_FILTER serve any purpose? Message-ID: <20150610065139.GA10200@gmail.com> References: <55773DA3.6070808@gmail.com> <20150609155506.3c7d5fc3@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150609155506.3c7d5fc3@gandalf.local.home> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1830 Lines: 51 * Steven Rostedt wrote: > On Tue, 9 Jun 2015 15:51:53 -0400 (EDT) > Vince Weaver wrote: > > > On Tue, 9 Jun 2015, David Ahern wrote: > > > > > On 6/9/15 12:30 PM, Vince Weaver wrote: > > > > Hello > > > > > > > > I've been working on documenting the PERF_EVENT_IOC_SET_FILTER ioctl. > > > > > > > > I've been trying for the past 2 days and have been unable to get any > > > > result except EINVAL. > > > > > > > > Does anyone ever use this ioctl? Does anyone know how to use this ioctl? > > > > > > yes and yes it works. > > > > > > perf record -e irq:irq_handler_entry --filter irq==28 \ > > > -e irq:softirq_entry --filter vec==6 -a \ > > > -- sleep 5 > > > > # perf record -e irq:irq_handler_entry --filter irq==28 -e irq:softirq_entry --filter vec==6 -a -- sleep 5 > > invalid or unsupported event: 'irq:irq_handler_entry' > > Run 'perf list' for a list of valid events > > > > perf list doesn't show any tracepoint events, despite having debugfs > > mounted and running as root and /sys/kernel/debug/tracing/events/ being > > populated. > > > > What kernel are you using? You may need to update perf. > > We switched to a tracefs filesystem, but the old perf wont read any events if > it's not located in debugfs. That is, it actually tested which filesystem the > event files were mounted on, and if they didn't match the debugfs mount type, it > ignored them. That was fixed recently. That fix should probably be backported to stable kernels, to keep old instances working. Thanks, Ingo -- 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/