From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758882AbZEFE01 (ORCPT ); Wed, 6 May 2009 00:26:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751114AbZEFEXm (ORCPT ); Wed, 6 May 2009 00:23:42 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.125]:39814 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751014AbZEFEXe (ORCPT ); Wed, 6 May 2009 00:23:34 -0400 Message-Id: <20090506042334.272154001@goodmis.org> References: <20090506042101.231470089@goodmis.org> User-Agent: quilt/0.46-1 Date: Wed, 06 May 2009 00:21:08 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Frederic Weisbecker Subject: [PATCH 07/11] ring-buffer: disable writers when resetting buffers Content-Disposition: inline; filename=0007-ring-buffer-disable-writers-when-resetting-buffers.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Steven Rostedt As a precaution, it is best to disable writing to the ring buffers when reseting them. [ Impact: prevent weird things if write happens during reset ] Signed-off-by: Steven Rostedt --- kernel/trace/ring_buffer.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 9e42a74..7876df0 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -2650,6 +2650,8 @@ void ring_buffer_reset_cpu(struct ring_buffer *buffer, int cpu) if (!cpumask_test_cpu(cpu, buffer->cpumask)) return; + atomic_inc(&cpu_buffer->record_disabled); + spin_lock_irqsave(&cpu_buffer->reader_lock, flags); __raw_spin_lock(&cpu_buffer->lock); @@ -2659,6 +2661,8 @@ void ring_buffer_reset_cpu(struct ring_buffer *buffer, int cpu) __raw_spin_unlock(&cpu_buffer->lock); spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); + + atomic_dec(&cpu_buffer->record_disabled); } EXPORT_SYMBOL_GPL(ring_buffer_reset_cpu); -- 1.6.2.4 --