From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752287AbdBHX3V (ORCPT ); Wed, 8 Feb 2017 18:29:21 -0500 Received: from mga01.intel.com ([192.55.52.88]:40740 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752047AbdBHX3S (ORCPT ); Wed, 8 Feb 2017 18:29:18 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.35,348,1484035200"; d="scan'208";a="41735018" Message-ID: <1486596530.2871.22.camel@tzanussi-mobl.amr.corp.intel.com> Subject: Re: [RFC][PATCH 00/21] tracing: Inter-event (e.g. latency) support From: Tom Zanussi To: Steven Rostedt Cc: tglx@linutronix.de, mhiramat@kernel.org, namhyung@kernel.org, linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org Date: Wed, 08 Feb 2017 17:28:50 -0600 In-Reply-To: <20170208150109.5919a2ea@gandalf.local.home> References: <20170208150109.5919a2ea@gandalf.local.home> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4 (3.10.4-4.fc20) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2017-02-08 at 15:01 -0500, Steven Rostedt wrote: > On Wed, 8 Feb 2017 11:24:56 -0600 > Tom Zanussi wrote: > > > # echo 'wakeup_latency lat=sched_switch:wakeup_lat \ > > pid=sched_switch:woken_pid \ > > prio=sched_switch:woken_prio' >> \ > > /sys/kernel/debug/tracing/synthetic_events > > I applied all your patches, did the above and then: > > BUG: unable to handle kernel NULL pointer dereference at 0000000000000034 > IP: free_synthetic_event+0x46/0xb0 > PGD 0 > OK, well, the problem is actually the '\' 'continuation' characters in the above string. I'll fix that properly, but in the meantime, removing those chars in the documentation strings will let you try it out i.e. # echo 'wakeup_latency lat=sched_switch:wakeup_lat pid=sched_switch:woken_pid prio=sched_switch:woken_prio' >> /sys/kernel/debug/tracing/synthetic_events Tom