From: "Paul E. McKenney" <paulmck@kernel.org>
To: fweisbec@gmail.com, tglx@linutronix.de, mingo@kernel.org
Cc: linux-kernel@vger.kernel.org, luto@kernel.org, kernel-team@fb.com
Subject: [PATCH tick-sched] Clarify "NOHZ: local_softirq_pending" warning
Date: Fri, 26 Jun 2020 14:05:06 -0700 [thread overview]
Message-ID: <20200626210506.GA27189@paulmck-ThinkPad-P72> (raw)
Currently, can_stop_idle_tick() prints "NOHZ: local_softirq_pending HH"
(where "HH" is the hexadecimal softirq vector number) when one or more
non-RCU softirq handlers are still enablded when checking to stop the
scheduler-tick interrupt. This message is not as enlightening as one
might hope, so this commit changes it to "NOHZ tick-stop error: Non-RCU
local softirq work is pending, handler #HH.
Reported-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
tick-sched.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index f0199a4..349a25a 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -927,7 +927,7 @@ static bool can_stop_idle_tick(int cpu, struct tick_sched *ts)
if (ratelimit < 10 &&
(local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK)) {
- pr_warn("NOHZ: local_softirq_pending %02x\n",
+ pr_warn("NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #%02x\n",
(unsigned int) local_softirq_pending());
ratelimit++;
}
next reply other threads:[~2020-06-26 21:05 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-26 21:05 Paul E. McKenney [this message]
2020-06-27 21:02 ` [PATCH tick-sched] Clarify "NOHZ: local_softirq_pending" warning Andy Lutomirski
2020-06-27 21:46 ` Paul E. McKenney
2020-06-27 22:14 ` Andy Lutomirski
2020-06-27 23:44 ` Paul E. McKenney
2020-07-06 16:48 ` Qian Cai
2020-07-06 17:06 ` Paul E. McKenney
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