From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757199AbZJHCJO (ORCPT ); Wed, 7 Oct 2009 22:09:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756597AbZJHCJA (ORCPT ); Wed, 7 Oct 2009 22:09:00 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.125]:45094 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756804AbZJHCI6 (ORCPT ); Wed, 7 Oct 2009 22:08:58 -0400 Message-Id: <20091008020700.433266812@goodmis.org> User-Agent: quilt/0.48-1 Date: Wed, 07 Oct 2009 22:06:27 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Frederic Weisbecker , Li Zefan Subject: [PATCH 2/2] [PATCH 2/2] tracing: user local buffer variable for trace branch tracer References: <20091008020625.084181867@goodmis.org> Content-Disposition: inline; filename=0002-tracing-user-local-buffer-variable-for-trace-branch-.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Steven Rostedt Just using the tr->buffer for the API to trace_buffer_lock_reserve is not good enough. This is because the tr->buffer may change, and we do not want to commit with a different buffer that we reserved from. This patch uses a local variable to hold the buffer that was used to reserve and commit with. Signed-off-by: Steven Rostedt --- kernel/trace/trace_branch.c | 8 +++++--- 1 files changed, 5 insertions(+), 3 deletions(-) diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c index 216e2dd..4a194f0 100644 --- a/kernel/trace/trace_branch.c +++ b/kernel/trace/trace_branch.c @@ -34,6 +34,7 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect) struct trace_array *tr = branch_tracer; struct ring_buffer_event *event; struct trace_branch *entry; + struct ring_buffer *buffer; unsigned long flags; int cpu, pc; const char *p; @@ -54,7 +55,8 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect) goto out; pc = preempt_count(); - event = trace_buffer_lock_reserve(tr->buffer, TRACE_BRANCH, + buffer = tr->buffer; + event = trace_buffer_lock_reserve(buffer, TRACE_BRANCH, sizeof(*entry), flags, pc); if (!event) goto out; @@ -74,8 +76,8 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect) entry->line = f->line; entry->correct = val == expect; - if (!filter_check_discard(call, entry, tr->buffer, event)) - ring_buffer_unlock_commit(tr->buffer, event); + if (!filter_check_discard(call, entry, buffer, event)) + ring_buffer_unlock_commit(buffer, event); out: atomic_dec(&tr->data[cpu]->disabled); -- 1.6.3.3