From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932065AbZEDPWA (ORCPT ); Mon, 4 May 2009 11:22:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757234AbZEDPUZ (ORCPT ); Mon, 4 May 2009 11:20:25 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.124]:45334 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756156AbZEDPUV (ORCPT ); Mon, 4 May 2009 11:20:21 -0400 Message-Id: <20090504152021.349097001@goodmis.org> References: <20090504151933.728781787@goodmis.org> User-Agent: quilt/0.46-1 Date: Mon, 04 May 2009 11:19:39 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Frederic Weisbecker Subject: [PATCH 6/6] ring-buffer: disable writers when resetting buffers Content-Disposition: inline; filename=0006-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 7ff1f57..24372d1 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -2649,6 +2649,8 @@ 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); @@ -2658,6 +2660,8 @@ 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 --