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From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     rcu@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, kernel-team@meta.com,
        rostedt@goodmis.org, "Paul E. McKenney" <paulmck@kernel.org>
Subject: [PATCH rcu 1/9] rcutorture: Dump grace-period state upon rtort_pipe_count incidents
Date:   Mon, 17 Jul 2023 11:20:34 -0700
Message-Id: <20230717182042.1098651-1-paulmck@kernel.org>
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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@kernel.org>
---
 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