watchdog/sysctl: Clean up sysctl variable name space

Reflect that these variables are user interface related and remove the
whitespace damage in the sysctl table while at it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Link: http://lkml.kernel.org/r/20170912194147.783210221@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

include/linux/nmi.h

@@ -17,8 +17,8 @@ void lockup_detector_cleanup(void);
 bool is_hardlockup(void);
 
 extern int watchdog_user_enabled;
-extern int nmi_watchdog_enabled;
-extern int soft_watchdog_enabled;
+extern int nmi_watchdog_user_enabled;
+extern int soft_watchdog_user_enabled;
 extern int watchdog_thresh;
 extern unsigned long watchdog_enabled;
 
@@ -62,12 +62,12 @@ static inline void reset_hung_task_detector(void) { }
  * 'watchdog_enabled' variable. Each lockup detector has its dedicated bit -
  * bit 0 for the hard lockup detector and bit 1 for the soft lockup detector.
  *
- * 'watchdog_user_enabled', 'nmi_watchdog_enabled' and 'soft_watchdog_enabled'
- * are variables that are only used as an 'interface' between the parameters
- * in /proc/sys/kernel and the internal state bits in 'watchdog_enabled'. The
- * 'watchdog_thresh' variable is handled differently because its value is not
- * boolean, and the lockup detectors are 'suspended' while 'watchdog_thresh'
- * is equal zero.
+ * 'watchdog_user_enabled', 'nmi_watchdog_user_enabled' and
+ * 'soft_watchdog_user_enabled' are variables that are only used as an
+ * 'interface' between the parameters in /proc/sys/kernel and the internal
+ * state bits in 'watchdog_enabled'. The 'watchdog_thresh' variable is
+ * handled differently because its value is not boolean, and the lockup
+ * detectors are 'suspended' while 'watchdog_thresh' is equal zero.
  */
 #define NMI_WATCHDOG_ENABLED_BIT   0
 #define SOFT_WATCHDOG_ENABLED_BIT  1

kernel/sysctl.c

@@ -889,7 +889,7 @@ static struct ctl_table kern_table[] = {
 	},
 	{
 		.procname       = "nmi_watchdog",
-		.data           = &nmi_watchdog_enabled,
+		.data		= &nmi_watchdog_user_enabled,
 		.maxlen		= sizeof(int),
 		.mode		= NMI_WATCHDOG_SYSCTL_PERM,
 		.proc_handler   = proc_nmi_watchdog,
@@ -906,7 +906,7 @@ static struct ctl_table kern_table[] = {
 #ifdef CONFIG_SOFTLOCKUP_DETECTOR
 	{
 		.procname       = "soft_watchdog",
-		.data           = &soft_watchdog_enabled,
+		.data		= &soft_watchdog_user_enabled,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
 		.proc_handler   = proc_soft_watchdog,

kernel/watchdog.c

@@ -31,8 +31,6 @@
 
 static DEFINE_MUTEX(watchdog_mutex);
 
-int __read_mostly nmi_watchdog_enabled;
-
 #if defined(CONFIG_HARDLOCKUP_DETECTOR) || defined(CONFIG_HAVE_NMI_WATCHDOG)
 unsigned long __read_mostly watchdog_enabled = SOFT_WATCHDOG_ENABLED |
 						NMI_WATCHDOG_ENABLED;
@@ -40,6 +38,17 @@ unsigned long __read_mostly watchdog_enabled = SOFT_WATCHDOG_ENABLED |
 unsigned long __read_mostly watchdog_enabled = SOFT_WATCHDOG_ENABLED;
 #endif
 
+int __read_mostly nmi_watchdog_user_enabled;
+int __read_mostly soft_watchdog_user_enabled;
+int __read_mostly watchdog_user_enabled;
+int __read_mostly watchdog_thresh = 10;
+
+struct cpumask watchdog_allowed_mask __read_mostly;
+static bool softlockup_threads_initialized __read_mostly;
+
+struct cpumask watchdog_cpumask __read_mostly;
+unsigned long *watchdog_cpumask_bits = cpumask_bits(&watchdog_cpumask);
+
 #ifdef CONFIG_HARDLOCKUP_DETECTOR
 /*
  * Should we panic when a soft-lockup or hard-lockup occurs:
@@ -85,12 +94,6 @@ __setup("hardlockup_all_cpu_backtrace=", hardlockup_all_cpu_backtrace_setup);
 # endif /* CONFIG_SMP */
 #endif /* CONFIG_HARDLOCKUP_DETECTOR */
 
-int __read_mostly watchdog_user_enabled;
-int __read_mostly watchdog_thresh = 10;
-
-struct cpumask watchdog_cpumask __read_mostly;
-unsigned long *watchdog_cpumask_bits = cpumask_bits(&watchdog_cpumask);
-
 /*
  * These functions can be overridden if an architecture implements its
  * own hardlockup detector.
@@ -113,7 +116,7 @@ void __weak watchdog_nmi_disable(unsigned int cpu)
  * watchdog_nmi_reconfigure can be implemented to be notified after any
  * watchdog configuration change. The arch hardlockup watchdog should
  * respond to the following variables:
- * - nmi_watchdog_enabled
+ * - watchdog_enabled
  * - watchdog_thresh
  * - watchdog_cpumask
  * - sysctl_hardlockup_all_cpu_backtrace
@@ -126,10 +129,6 @@ void __weak watchdog_nmi_reconfigure(void) { }
 /* Global variables, exported for sysctl */
 unsigned int __read_mostly softlockup_panic =
 			CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC_VALUE;
-int __read_mostly soft_watchdog_enabled;
-
-struct cpumask watchdog_allowed_mask __read_mostly;
-static bool softlockup_threads_initialized __read_mostly;
 
 static u64 __read_mostly sample_period;
 
@@ -606,14 +605,14 @@ static void proc_watchdog_update(void)
 /*
  * common function for watchdog, nmi_watchdog and soft_watchdog parameter
  *
- * caller             | table->data points to | 'which' contains the flag(s)
- * -------------------|-----------------------|-----------------------------
- * proc_watchdog      | watchdog_user_enabled | NMI_WATCHDOG_ENABLED or'ed
- *                    |                       | with SOFT_WATCHDOG_ENABLED
- * -------------------|-----------------------|-----------------------------
- * proc_nmi_watchdog  | nmi_watchdog_enabled  | NMI_WATCHDOG_ENABLED
- * -------------------|-----------------------|-----------------------------
- * proc_soft_watchdog | soft_watchdog_enabled | SOFT_WATCHDOG_ENABLED
+ * caller             | table->data points to      | 'which'
+ * -------------------|----------------------------|--------------------------
+ * proc_watchdog      | watchdog_user_enabled      | NMI_WATCHDOG_ENABLED |
+ *                    |                            | SOFT_WATCHDOG_ENABLED
+ * -------------------|----------------------------|--------------------------
+ * proc_nmi_watchdog  | nmi_watchdog_user_enabled  | NMI_WATCHDOG_ENABLED
+ * -------------------|----------------------------|--------------------------
+ * proc_soft_watchdog | soft_watchdog_user_enabled | SOFT_WATCHDOG_ENABLED
  */
 static int proc_watchdog_common(int which, struct ctl_table *table, int write,
 				void __user *buffer, size_t *lenp, loff_t *ppos)