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* [PATCH] Add comments to explain watchdog_disabled variable
@ 2013-03-12 18:44 Don Zickus
  2013-03-18 11:00 ` [tip:perf/core] watchdog: Add comments to explain the " tip-bot for anish kumar
  0 siblings, 1 reply; 2+ messages in thread
From: Don Zickus @ 2013-03-12 18:44 UTC (permalink / raw)
  To: akpm; +Cc: LKML, mingo, chuansheng.liu, paulmck, anish kumar, Don Zickus

From: anish kumar <anish198519851985@gmail.com>

This watchdog_disabled flag is a bit cryptic. However it's usefulness is multifold.
Uses are:
1. Check if smpboot_register_percpu_thread function passed.
2. Makes sure that user enables and disables the watchdog in sequence
   i.e. enable watchdog->disable watchdog->enable watchdog
   Unlike enable watchdog->enable watchdog which is wrong.

Signed-off-by: anish kumar <anish198519851985@gmail.com>
[small text cleanups]
Signed-off-by: Don Zickus <dzickus@redhat.com>
---
 kernel/watchdog.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 75a2ab3..238477b 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -518,6 +518,11 @@ int proc_dowatchdog(struct ctl_table *table, int write,
 		return ret;
 
 	set_sample_period();
+	/*
+	 * Watchdog threads shouldn't be enabled if they are
+	 * disabled. The 'watchdog_disabled' variable check in
+	 * watchdog_*_all_cpus() function takes care of this.
+	 */
 	if (watchdog_enabled && watchdog_thresh)
 		watchdog_enable_all_cpus();
 	else
-- 
1.7.1


^ permalink raw reply related	[flat|nested] 2+ messages in thread

* [tip:perf/core] watchdog: Add comments to explain the watchdog_disabled variable
  2013-03-12 18:44 [PATCH] Add comments to explain watchdog_disabled variable Don Zickus
@ 2013-03-18 11:00 ` tip-bot for anish kumar
  0 siblings, 0 replies; 2+ messages in thread
From: tip-bot for anish kumar @ 2013-03-18 11:00 UTC (permalink / raw)
  To: linux-tip-commits
  Cc: linux-kernel, hpa, mingo, anish198519851985, tglx, dzickus

Commit-ID:  b66a2356d7108a15b8b5c9b8e6213e05ead22cd6
Gitweb:     http://git.kernel.org/tip/b66a2356d7108a15b8b5c9b8e6213e05ead22cd6
Author:     anish kumar <anish198519851985@gmail.com>
AuthorDate: Tue, 12 Mar 2013 14:44:08 -0400
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Thu, 14 Mar 2013 08:24:05 +0100

watchdog: Add comments to explain the watchdog_disabled variable

The watchdog_disabled flag is a bit cryptic. However it's
usefulness is multifold. Uses are:

 1. Check if smpboot_register_percpu_thread function passed.

 2. Makes sure that user enables and disables the watchdog in
    sequence i.e. enable watchdog->disable watchdog->enable watchdog
    Unlike enable watchdog->enable watchdog which is wrong.

Signed-off-by: anish kumar <anish198519851985@gmail.com>
[small text cleanups]
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: chuansheng.liu@intel.com
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1363113848-18344-1-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 kernel/watchdog.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 4a94467..05039e3 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -517,6 +517,11 @@ int proc_dowatchdog(struct ctl_table *table, int write,
 		return ret;
 
 	set_sample_period();
+	/*
+	 * Watchdog threads shouldn't be enabled if they are
+	 * disabled. The 'watchdog_disabled' variable check in
+	 * watchdog_*_all_cpus() function takes care of this.
+	 */
 	if (watchdog_enabled && watchdog_thresh)
 		watchdog_enable_all_cpus();
 	else

^ permalink raw reply related	[flat|nested] 2+ messages in thread

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