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From: Frederic Weisbecker <fweisbec@gmail.com>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
	Don Zickus <dzickus@redhat.com>, Ingo Molnar <mingo@kernel.org>,
	Peter Zijlstra <peterz@infradead.org>
Subject: [RFC PATCH 8/8] watchdog: Fix internal state with boot user disabled watchdog
Date: Mon, 20 May 2013 18:01:56 +0200	[thread overview]
Message-ID: <1369065716-22801-9-git-send-email-fweisbec@gmail.com> (raw)
In-Reply-To: <1369065716-22801-1-git-send-email-fweisbec@gmail.com>

When the watchdog is disabled through the 'nmi_watchdog=0'
boot parameter, the watchdog_running internal state isn't
cleared. Hence further enablements through sysctl/procfs
are ignored because the subsystem spuriously thinks it's
already running.

Initialize it properly on boot.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
---
 kernel/watchdog.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 10776fe..3fa5df20 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -31,7 +31,7 @@
 
 int watchdog_user_enabled = 1;
 int __read_mostly watchdog_thresh = 10;
-static int __read_mostly watchdog_running = 1;
+static int __read_mostly watchdog_running;
 static u64 __read_mostly sample_period;
 
 static DEFINE_PER_CPU(unsigned long, watchdog_touch_ts);
@@ -545,10 +545,10 @@ void __init lockup_detector_init(void)
 {
 #ifdef CONFIG_NO_HZ_FULL
 	watchdog_user_enabled = 0;
-	watchdog_running = 0;
 	pr_warning("Disabled lockup detectors by default because of full dynticks\n");
 	pr_warning("You can overwrite that with 'sysctl -w kernel.watchdog=1'\n");
 #endif
+	watchdog_running = watchdog_user_enabled;
 	set_sample_period();
 	if (smpboot_register_percpu_thread(&watchdog_threads)) {
 		pr_err("Failed to create watchdog threads, disabled\n");
-- 
1.7.5.4


  parent reply	other threads:[~2013-05-20 16:02 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-05-20 16:01 [PATCH 0/8] nohz: Random fixes Frederic Weisbecker
2013-05-20 16:01 ` [PATCH 1/8] nohz: Warn if the machine can not perform nohz_full Frederic Weisbecker
2013-05-20 16:01 ` [PATCH 2/8] vtime: Use consistent clocks among nohz accounting Frederic Weisbecker
2013-06-03  9:47   ` Stefan Seyfried
2013-06-03 13:48     ` Steven Rostedt
2013-06-03 19:48     ` Frederic Weisbecker
2013-06-03 19:51       ` Stefan Seyfried
2013-06-03 20:12         ` Frederic Weisbecker
2013-05-20 16:01 ` [PATCH 3/8] watchdog: Boot-disable by default on full dynticks Frederic Weisbecker
2013-05-20 17:52   ` Don Zickus
2013-05-20 18:14     ` Frederic Weisbecker
2013-05-20 16:01 ` [PATCH 4/8] kvm: Move guest entry/exit APIs to context_tracking Frederic Weisbecker
2013-05-20 16:01 ` [PATCH 5/8] nohz: Fix notifier return val that enforce timekeeping Frederic Weisbecker
2013-05-20 16:01 ` [RFC PATCH 6/8] kthread: Enable parking requests from setup() and unpark() callbacks Frederic Weisbecker
2013-05-21  5:34   ` anish singh
2013-05-21  7:49     ` Srivatsa S. Bhat
2013-05-21  8:58       ` anish singh
2013-05-21  9:07         ` Srivatsa S. Bhat
2013-05-22 15:18         ` Frederic Weisbecker
2013-05-21  6:59   ` Srivatsa S. Bhat
2013-06-05 16:33     ` Frederic Weisbecker
2013-05-20 16:01 ` [RFC PATCH 7/8] watchdog: Rename confusing state variable Frederic Weisbecker
2013-05-20 17:53   ` Don Zickus
2013-05-20 16:01 ` Frederic Weisbecker [this message]
2013-05-20 17:54   ` [RFC PATCH 8/8] watchdog: Fix internal state with boot user disabled watchdog Don Zickus

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