From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754365AbZCRJTc (ORCPT ); Wed, 18 Mar 2009 05:19:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755850AbZCRJTH (ORCPT ); Wed, 18 Mar 2009 05:19:07 -0400 Received: from hera.kernel.org ([140.211.167.34]:57618 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755637AbZCRJTF (ORCPT ); Wed, 18 Mar 2009 05:19:05 -0400 Date: Wed, 18 Mar 2009 09:18:28 GMT From: Thomas Gleixner To: linux-tip-commits@vger.kernel.org Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, fweisbec@gmail.com, srostedt@redhat.com, tglx@linutronix.de, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, fweisbec@gmail.com, srostedt@redhat.com, tglx@linutronix.de, mingo@elte.hu In-Reply-To: References: Subject: [tip:tracing/tasks] tracing: stop command line recording when tracing is disabled Message-ID: Git-Commit-ID: 18aecd362a1c991fbf5f7919ae051a77532ba2f8 X-Mailer: tip-git-log-daemon MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.0 (hera.kernel.org [127.0.0.1]); Wed, 18 Mar 2009 09:18:30 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 18aecd362a1c991fbf5f7919ae051a77532ba2f8 Gitweb: http://git.kernel.org/tip/18aecd362a1c991fbf5f7919ae051a77532ba2f8 Author: Thomas Gleixner AuthorDate: Wed, 18 Mar 2009 08:56:58 +0100 Commit: Ingo Molnar CommitDate: Wed, 18 Mar 2009 10:10:16 +0100 tracing: stop command line recording when tracing is disabled Impact: prevent overwrite of command line entries When the tracer is stopped the command line recording continues to record. The check for tracing_is_on() is not sufficient here as the ringbuffer status is not affected by setting debug/tracing/tracing_enabled to 0. On a non idle system this can result in the loss of the command line information for the stopped trace, which makes the trace harder to read and analyse. Check tracer_enabled to allow further recording. Signed-off-by: Thomas Gleixner Cc: Steven Rostedt Cc: Frederic Weisbecker LKML-Reference: Signed-off-by: Ingo Molnar --- kernel/trace/trace.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 1ce6208..7b6043e 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -797,7 +797,8 @@ void trace_find_cmdline(int pid, char comm[]) void tracing_record_cmdline(struct task_struct *tsk) { - if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) + if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || + !tracing_is_on()) return; trace_save_cmdline(tsk);