rcu/torture: Change order of warning and trace dump

Dumping a big ftrace buffer could lead to a RCU stall. So there is the
ftrace buffer and the stall information which needs to be printed. When
there is additionally a WARN_ON() which describes the reason for the ftrace
buffer dump and the WARN_ON() is executed _after_ ftrace buffer dump, the
information get lost in the middle of the RCU stall information.

Therefore print WARN_ON() message before dumping the ftrace buffer in
rcu_torture_writer().

[ paulmck: Add tracing_off() to avoid cruft from WARN(). ]

Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Reviewed-by: Benedikt Spranger <b.spranger@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 7120165a93426c282c7d9f6d3a87a4738ac52905..3032dd7c7ad350c5501aa64387759aff7b324896 100644 (file)
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -1321,8 +1321,9 @@ rcu_torture_writer(void *arg)
                                if (list_empty(&rcu_tortures[i].rtort_free) &&
                                    rcu_access_pointer(rcu_torture_current) !=
                                    &rcu_tortures[i]) {
-                                       rcu_ftrace_dump(DUMP_ALL);
+                                       tracing_off();
                                        WARN(1, "%s: rtort_pipe_count: %d\n", __func__, rcu_tortures[i].rtort_pipe_count);
+                                       rcu_ftrace_dump(DUMP_ALL);
                                }
                if (stutter_waited)
                        sched_set_normal(current, oldnice);