From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756428AbZAUX7l (ORCPT ); Wed, 21 Jan 2009 18:59:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754586AbZAUX6M (ORCPT ); Wed, 21 Jan 2009 18:58:12 -0500 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.124]:60387 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754309AbZAUX6I (ORCPT ); Wed, 21 Jan 2009 18:58:08 -0500 Message-Id: <20090121235805.992357373@goodmis.org> References: <20090121235306.224764198@goodmis.org> User-Agent: quilt/0.46-1 Date: Wed, 21 Jan 2009 18:53:08 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Frederic Weisbecker , Steven Rostedt Subject: [PATCH 2/5] ring-buffer: do not swap if recording is disabled Content-Disposition: inline; filename=0002-ring-buffer-do-not-swap-if-recording-is-disabled.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Steven Rostedt If the ring buffer recording has been disabled. Do not let swapping of ring buffers occur. Simply return -EAGAIN. Signed-off-by: Steven Rostedt --- kernel/trace/ring_buffer.c | 15 +++++++++++++++ kernel/trace/trace.c | 2 +- 2 files changed, 16 insertions(+), 1 deletions(-) diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 8de026d..cb260dd 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -2266,9 +2266,24 @@ int ring_buffer_swap_cpu(struct ring_buffer *buffer_a, if (buffer_a->pages != buffer_b->pages) return -EINVAL; + if (ring_buffer_flags != RB_BUFFERS_ON) + return -EAGAIN; + + if (atomic_read(&buffer_a->record_disabled)) + return -EAGAIN; + + if (atomic_read(&buffer_b->record_disabled)) + return -EAGAIN; + cpu_buffer_a = buffer_a->buffers[cpu]; cpu_buffer_b = buffer_b->buffers[cpu]; + if (atomic_read(&cpu_buffer_a->record_disabled)) + return -EAGAIN; + + if (atomic_read(&cpu_buffer_b->record_disabled)) + return -EAGAIN; + /* * We can't do a synchronize_sched here because this * function can be called in atomic context. diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 220c264..757ae6f 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -415,7 +415,7 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) ftrace_enable_cpu(); - WARN_ON_ONCE(ret); + WARN_ON_ONCE(ret && ret != -EAGAIN); __update_max_tr(tr, tsk, cpu); __raw_spin_unlock(&ftrace_max_lock); -- 1.5.6.5 --