[patch V2 12/29] lockup_detector: Cleanup stub functions

[Thomas Gleixner]

Having stub functions which take a full page is not helping the
readablility of code.

Condense them and move the doubled #ifdef variant into the SYSFS section.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Don Zickus <dzickus@xxxxxxxxxx>
Cc: Chris Metcalf <cmetcalf@xxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Sebastian Siewior <bigeasy@xxxxxxxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Ulrich Obergfell <uobergfe@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/20170831073053.941973023@xxxxxxxxxxxxx

---
 kernel/watchdog.c |   68 +++++++++++++++++-------------------------------------
 1 file changed, 22 insertions(+), 46 deletions(-)

--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -125,10 +125,7 @@ void __weak watchdog_nmi_disable(unsigne
  * - sysctl_hardlockup_all_cpu_backtrace
  * - hardlockup_panic
  */
-void __weak watchdog_nmi_reconfigure(void)
-{
-}
-
+void __weak watchdog_nmi_reconfigure(void) { }
 
 #ifdef CONFIG_SOFTLOCKUP_DETECTOR
 
@@ -136,6 +133,11 @@ void __weak watchdog_nmi_reconfigure(voi
 #define for_each_watchdog_cpu(cpu) \
 	for_each_cpu_and((cpu), cpu_online_mask, &watchdog_cpumask)
 
+/* Global variables, exported for sysctl */
+unsigned int __read_mostly softlockup_panic =
+			CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC_VALUE;
+int __read_mostly soft_watchdog_enabled;
+
 static u64 __read_mostly sample_period;
 
 static DEFINE_PER_CPU(unsigned long, watchdog_touch_ts);
@@ -149,13 +151,9 @@ static DEFINE_PER_CPU(struct task_struct
 static DEFINE_PER_CPU(unsigned long, hrtimer_interrupts_saved);
 static unsigned long soft_lockup_nmi_warn;
 
-unsigned int __read_mostly softlockup_panic =
-			CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC_VALUE;
-
 static int __init softlockup_panic_setup(char *str)
 {
 	softlockup_panic = simple_strtoul(str, NULL, 0);
-
 	return 1;
 }
 __setup("softlockup_panic=", softlockup_panic_setup);
@@ -593,44 +591,13 @@ static void watchdog_disable_all_cpus(vo
 	}
 }
 
-#ifdef CONFIG_SYSCTL
-static int watchdog_update_cpus(void)
-{
-	return smpboot_update_cpumask_percpu_thread(
-		    &watchdog_threads, &watchdog_cpumask);
-}
-#endif
-
-#else /* SOFTLOCKUP */
-static int watchdog_park_threads(void)
-{
-	return 0;
-}
-
-static void watchdog_unpark_threads(void)
-{
-}
-
-static int watchdog_enable_all_cpus(void)
-{
-	return 0;
-}
-
-static void watchdog_disable_all_cpus(void)
-{
-}
-
-#ifdef CONFIG_SYSCTL
-static int watchdog_update_cpus(void)
-{
-	return 0;
-}
-#endif
-
-static void set_sample_period(void)
-{
-}
-#endif /* SOFTLOCKUP */
+#else /* CONFIG_SOFTLOCKUP_DETECTOR */
+static inline int watchdog_park_threads(void) { return 0; }
+static inline void watchdog_unpark_threads(void) { }
+static inline int watchdog_enable_all_cpus(void) { return 0; }
+static inline void watchdog_disable_all_cpus(void) { }
+static inline void set_sample_period(void) { }
+#endif /* !CONFIG_SOFTLOCKUP_DETECTOR */
 
 static void __lockup_detector_cleanup(void)
 {
@@ -827,6 +794,15 @@ int proc_watchdog_thresh(struct ctl_tabl
 	return err;
 }
 
+static int watchdog_update_cpus(void)
+{
+	if (IS_ENABLED(CONFIG_SOFTLOCKUP_DETECTOR)) {
+		return smpboot_update_cpumask_percpu_thread(&watchdog_threads,
+							    &watchdog_cpumask);
+	}
+	return 0;
+}
+
 /*
  * 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