[PATCH rcu 1/9] rcutorture: Dump grace-period state upon rtort_pipe_count incidents

From: Paul E. McKenney
Date: Mon Jul 17 2023 - 14:20:50 EST


The rtort_pipe_count WARN() indicates that grace periods were unable
to invoke all callbacks during a stutter_wait() interval. But it is
sometimes helpful to have a bit more information as to why. This commit
therefore invokes show_rcu_gp_kthreads() immediately before that WARN()
in order to dump out some relevant information.

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
kernel/rcu/rcutorture.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 147551c23baf..d291a1438c30 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -1581,6 +1581,7 @@ rcu_torture_writer(void *arg)
rcu_access_pointer(rcu_torture_current) !=
&rcu_tortures[i]) {
tracing_off();
+ show_rcu_gp_kthreads();
WARN(1, "%s: rtort_pipe_count: %d\n", __func__, rcu_tortures[i].rtort_pipe_count);
rcu_ftrace_dump(DUMP_ALL);
}
--
2.40.1