From: Nicholas Piggin <npiggin@gmail.com>
To: linuxppc-dev@lists.ozlabs.org
Cc: Nicholas Piggin <npiggin@gmail.com>,
Balbir Singh <bsingharora@gmail.com>
Subject: [PATCH v2 1/2] powerpc/watchdog: don't update the watchdog timestamp if a lockup is detected
Date: Sat, 5 May 2018 17:25:59 +1000 [thread overview]
Message-ID: <20180505072600.13270-2-npiggin@gmail.com> (raw)
In-Reply-To: <20180505072600.13270-1-npiggin@gmail.com>
The watchdog heartbeat timestamp is updated when the local heartbeat
timer fires (or touch_nmi_watchdog() is called).
This is an interesting data point, so don't overwrite it when the
soft-NMI interrupt detects a hard lockup. That code came from a pre-
merge version to prevent hard lockup messages flood, but that's taken
care of with the stuck CPU logic now, so there is no reason to
update the heartbeat timestamp here.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
arch/powerpc/kernel/watchdog.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/arch/powerpc/kernel/watchdog.c b/arch/powerpc/kernel/watchdog.c
index 6256dc3b0087..0bc701f9ab35 100644
--- a/arch/powerpc/kernel/watchdog.c
+++ b/arch/powerpc/kernel/watchdog.c
@@ -245,8 +245,6 @@ void soft_nmi_interrupt(struct pt_regs *regs)
tb = get_tb();
if (tb - per_cpu(wd_timer_tb, cpu) >= wd_panic_timeout_tb) {
- per_cpu(wd_timer_tb, cpu) = tb;
-
wd_smp_lock(&flags);
if (cpumask_test_cpu(cpu, &wd_smp_cpus_stuck)) {
wd_smp_unlock(&flags);
--
2.17.0
next prev parent reply other threads:[~2018-05-05 7:26 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-05-05 7:25 [PATCH v2 0/2] powerpc/watchdog: provide more data in watchdog messages Nicholas Piggin
2018-05-05 7:25 ` Nicholas Piggin [this message]
2018-05-10 14:06 ` [v2, 1/2] powerpc/watchdog: don't update the watchdog timestamp if a lockup is detected Michael Ellerman
2018-05-05 7:26 ` [PATCH v2 2/2] powerpc/watchdog: provide more data in watchdog messages Nicholas Piggin
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