From: Anna-Maria Behnsen <anna-maria@xxxxxxxxxxxxx>
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 additionaly 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@xxxxxxxxxxxxx>
Reviewed-by: Benedikt Spranger <b.spranger@xxxxxxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
kernel/rcu/rcutorture.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 7120165a93426..3032dd7c7ad35 100644
--- 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);
--
2.31.1.189.g2e36527f23
