[patch 18/29] lockup_detector: Further simplify sysctl handling

[Thomas Gleixner <tglx@linutronix.de>]

[-- Attachment #1: lockup_detector--Further-simplify-sysfs-handling.patch --]
[-- Type: text/plain, Size: 2662 bytes --]

Use a single function to update sysctl changes. This is not a high
frequency user space interface and it's root only.

Preparatory patch to cleanup the sysctl variable handling.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 kernel/watchdog.c |   27 +++++++--------------------
 1 file changed, 7 insertions(+), 20 deletions(-)

--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -501,11 +501,8 @@ static void softlockup_park_all_threads(
 	softlockup_update_smpboot_threads();
 }
 
-/*
- * Park threads which are not longer enabled and unpark threads which have
- * been newly enabled.
- */
-static void softlockup_update_threads(void)
+/* Unpark enabled threads */
+static void softlockup_unpark_threads(void)
 {
 	cpumask_copy(&watchdog_allowed_mask, &watchdog_cpumask);
 	softlockup_update_smpboot_threads();
@@ -516,7 +513,7 @@ static void softlockup_reconfigure_threa
 	softlockup_park_all_threads();
 	set_sample_period();
 	if (enabled)
-		softlockup_update_threads();
+		softlockup_unpark_threads();
 }
 
 /*
@@ -557,7 +554,6 @@ static inline void watchdog_unpark_threa
 static inline int watchdog_enable_all_cpus(void) { return 0; }
 static inline void watchdog_disable_all_cpus(void) { }
 static inline void softlockup_init_threads(void) { }
-static inline void softlockup_update_threads(void) { }
 static inline void softlockup_reconfigure_threads(bool enabled) { }
 #endif /* !CONFIG_SOFTLOCKUP_DETECTOR */
 
@@ -592,11 +588,11 @@ void lockup_detector_soft_poweroff(void)
 
 #ifdef CONFIG_SYSCTL
 
-/*
- * Update the run state of the lockup detectors.
- */
+/* Propagate any changes to the watchdog threads */
 static void proc_watchdog_update(void)
 {
+	/* Remove impossible cpus to keep sysctl output clean. */
+	cpumask_and(&watchdog_cpumask, &watchdog_cpumask, cpu_possible_mask);
 	softlockup_reconfigure_threads(watchdog_enabled && watchdog_thresh);
 	watchdog_nmi_reconfigure();
 }
@@ -715,15 +711,6 @@ int proc_watchdog_thresh(struct ctl_tabl
 	return err;
 }
 
-static void proc_watchdog_cpumask_update(void)
-{
-	/* Remove impossible cpus to keep sysctl output clean. */
-	cpumask_and(&watchdog_cpumask, &watchdog_cpumask, cpu_possible_mask);
-
-	softlockup_update_threads();
-	watchdog_nmi_reconfigure();
-}
-
 /*
  * The cpumask is the mask of possible cpus that the watchdog can run
  * on, not the mask of cpus it is actually running on.  This allows the
@@ -740,7 +727,7 @@ int proc_watchdog_cpumask(struct ctl_tab
 
 	err = proc_do_large_bitmap(table, write, buffer, lenp, ppos);
 	if (!err && write)
-		proc_watchdog_cpumask_update();
+		proc_watchdog_update();
 
 	mutex_unlock(&watchdog_mutex);
 	cpu_hotplug_enable();