From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756158Ab1KBSWu (ORCPT ); Wed, 2 Nov 2011 14:22:50 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.124]:53062 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753382Ab1KBSWt (ORCPT ); Wed, 2 Nov 2011 14:22:49 -0400 X-Authority-Analysis: v=1.1 cv=rFxaVhpzdNKRsWyFDFmDbYx/QEtlW7L1Gw9MiLxO4aw= c=1 sm=0 a=DJOu6W8zkUMA:10 a=5SG0PmZfjMsA:10 a=Q9fys5e9bTEA:10 a=ZycB6UtQUfgMyuk2+PxD7w==:17 a=d91OG6ziQ8P09lIm3SsA:9 a=PUjeQqilurYA:10 a=ZycB6UtQUfgMyuk2+PxD7w==:117 X-Cloudmark-Score: 0 X-Originating-IP: 74.67.80.29 Message-ID: <1320258167.4793.45.camel@gandalf.stny.rr.com> Subject: Re: [PATCH] tracing: Restore system filter behavior From: Steven Rostedt To: Li Zefan Cc: LKML Date: Wed, 02 Nov 2011 14:22:47 -0400 In-Reply-To: <4EAF46CF.8040408@cn.fujitsu.com> References: <4EAF46CF.8040408@cn.fujitsu.com> Content-Type: text/plain; charset="ISO-8859-15" X-Mailer: Evolution 3.0.3-2 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2011-11-01 at 09:09 +0800, Li Zefan wrote: > Though not all events have field 'prev_pid', it was allowed to do this: > > # echo 'prev_pid == 100' > events/sched/filter > > but commit 75b8e98263fdb0bfbdeba60d4db463259f1fe8a2 (tracing/filter: Swap > entire filter of events) broke it without any reason. I wouldn't say "without any reason" as there was a reason. But I'm not pleased with the way this all works still. # echo 'prev_pid == 100' > /debug/tracing/events/sched/filter # cat /debug/tracing/events/sched/filter prev_pid == 100 # cat /debug/tracing/events/sched/sched_migrate_task/filter none # echo 'orig_cpu == 1' > /debug/tracing/events/sched/sched_migrate_task/filter # cat /debug/tracing/events/sched/sched_migrate_task/filter orig_cpu == 1 # cat /debug/tracing/events/sched/filter prev_pid == 100 The above shows how things are just ambiguous. I have no problem in using the top filter to set multiple events. But the top filter should not keep the state of what was set. Perhaps just have system event filters always show default text. Like: # cat /debug/tracing/events/sched/filter ### global filter ### # Use this to set multiple event filters # Only affects events that have the event fields specified in the filter I'll add your patch, but are you OK with the above always printing for system event filters? Just to remove the ambiguous state. -- Steve