[tip:timers/core] watchdog: Mark watchdog_hrtimer to expire in hard interrupt context - tip-bot for Sebastian Andrzej Siewior

From: tip-bot for Sebastian Andrzej Siewior <tipbot@zytor.com>
To: linux-tip-commits@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, bigeasy@linutronix.de,
	mingo@kernel.org, hpa@zytor.com, peterz@infradead.org,
	tglx@linutronix.de
Subject: [tip:timers/core] watchdog: Mark watchdog_hrtimer to expire in hard interrupt context
Date: Thu, 1 Aug 2019 12:00:24 -0700	[thread overview]
Message-ID: <tip-d2ab4cf4943576fb060b8a69341d9e0c2a952ba7@git.kernel.org> (raw)
In-Reply-To: <20190726185753.262895510@linutronix.de>

Commit-ID:  d2ab4cf4943576fb060b8a69341d9e0c2a952ba7
Gitweb:     https://git.kernel.org/tip/d2ab4cf4943576fb060b8a69341d9e0c2a952ba7
Author:     Sebastian Andrzej Siewior <bigeasy@linutronix.de>
AuthorDate: Fri, 26 Jul 2019 20:30:54 +0200
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Thu, 1 Aug 2019 20:51:20 +0200

watchdog: Mark watchdog_hrtimer to expire in hard interrupt context

The watchdog hrtimer must expire in hard interrupt context even on
PREEMPT_RT=y kernels as otherwise the hard/softlockup detection logic would
not work.

No functional change.

[ tglx: Split out from larger combo patch. Added changelog ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.262895510@linutronix.de



---
 kernel/watchdog.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 7f9e7b9306fe..f41334ef0971 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -490,10 +490,10 @@ static void watchdog_enable(unsigned int cpu)
 	 * Start the timer first to prevent the NMI watchdog triggering
 	 * before the timer has a chance to fire.
 	 */
-	hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD);
 	hrtimer->function = watchdog_timer_fn;
 	hrtimer_start(hrtimer, ns_to_ktime(sample_period),
-		      HRTIMER_MODE_REL_PINNED);
+		      HRTIMER_MODE_REL_PINNED_HARD);
 
 	/* Initialize timestamp */
 	__touch_watchdog();
