From: Steven Rostedt (Red Hat) <rostedt@goodmis.org>
Date: Mon, 26 Oct 2015 07:45:22 +0000 (-0400)
Subject: tracing: Fix sparse RCU warning
X-Git-Tag: v4.4-rc1~85^2~27
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;ds=sidebyside;h=fb662288284e8f2ec26f13d50a6b0d5781771648;p=linux.git

tracing: Fix sparse RCU warning

p_start() and p_stop() are seq_file functions that match. Teach sparse to
know that rcu_read_lock_sched() that is taken by p_start() is released by
p_stop.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---

diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 2b7fccd499c6..fb0261e90acc 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -938,6 +938,7 @@ static void t_stop(struct seq_file *m, void *p)
 }
 
 static void *p_start(struct seq_file *m, loff_t *pos)
+	__acquires(RCU)
 {
 	struct trace_pid_list *pid_list;
 	struct trace_array *tr = m->private;
@@ -960,6 +961,7 @@ static void *p_start(struct seq_file *m, loff_t *pos)
 }
 
 static void p_stop(struct seq_file *m, void *p)
+	__releases(RCU)
 {
 	rcu_read_unlock_sched();
 	mutex_unlock(&event_mutex);