watchdog: use suspend/resume interface in fixup_ht_bug()

Remove watchdog_nmi_disable_all() and watchdog_nmi_enable_all() since
these functions are no longer needed.  If a subsystem has a need to
deactivate the watchdog temporarily, it should utilize the
watchdog_suspend() and watchdog_resume() functions.

[akpm@linux-foundation.org: fix build with CONFIG_LOCKUP_DETECTOR=m]
Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Stephane Eranian <eranian@google.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/x86/kernel/cpu/perf_event_intel.c

@@ -3627,7 +3627,10 @@ static __init int fixup_ht_bug(void)
 		return 0;
 	}
 
-	watchdog_nmi_disable_all();
+	if (watchdog_suspend() != 0) {
+		pr_debug("failed to disable PMU erratum BJ122, BV98, HSD29 workaround\n");
+		return 0;
+	}
 
 	x86_pmu.flags &= ~(PMU_FL_EXCL_CNTRS | PMU_FL_EXCL_ENABLED);
 
@@ -3635,7 +3638,7 @@ static __init int fixup_ht_bug(void)
 	x86_pmu.commit_scheduling = NULL;
 	x86_pmu.stop_scheduling = NULL;
 
-	watchdog_nmi_enable_all();
+	watchdog_resume();
 
 	get_online_cpus();
 

include/linux/nmi.h

@@ -26,12 +26,8 @@ static inline void touch_nmi_watchdog(void)
 
 #if defined(CONFIG_HARDLOCKUP_DETECTOR)
 extern void hardlockup_detector_disable(void);
-void watchdog_nmi_disable_all(void);
-void watchdog_nmi_enable_all(void);
 #else
 static inline void hardlockup_detector_disable(void) {}
-static inline void watchdog_nmi_disable_all(void) {}
-static inline void watchdog_nmi_enable_all(void) {}
 #endif
 
 /*
@@ -84,6 +80,15 @@ extern int proc_watchdog_cpumask(struct ctl_table *, int,
 				 void __user *, size_t *, loff_t *);
 extern int watchdog_suspend(void);
 extern void watchdog_resume(void);
+#else
+static inline int watchdog_suspend(void)
+{
+	return 0;
+}
+
+static inline void watchdog_resume(void)
+{
+}
 #endif
 
 #ifdef CONFIG_HAVE_ACPI_APEI_NMI

kernel/watchdog.c

@@ -615,41 +615,6 @@ static void watchdog_nmi_disable(unsigned int cpu)
 	}
 }
 
-void watchdog_nmi_enable_all(void)
-{
-	int cpu;
-
-	mutex_lock(&watchdog_proc_mutex);
-
-	if (!(watchdog_enabled & NMI_WATCHDOG_ENABLED))
-		goto unlock;
-
-	get_online_cpus();
-	for_each_watchdog_cpu(cpu)
-		watchdog_nmi_enable(cpu);
-	put_online_cpus();
-
-unlock:
-	mutex_unlock(&watchdog_proc_mutex);
-}
-
-void watchdog_nmi_disable_all(void)
-{
-	int cpu;
-
-	mutex_lock(&watchdog_proc_mutex);
-
-	if (!watchdog_running)
-		goto unlock;
-
-	get_online_cpus();
-	for_each_watchdog_cpu(cpu)
-		watchdog_nmi_disable(cpu);
-	put_online_cpus();
-
-unlock:
-	mutex_unlock(&watchdog_proc_mutex);
-}
 #else
 static int watchdog_nmi_enable(unsigned int cpu) { return 0; }
 static void watchdog_nmi_disable(unsigned int cpu) { return; }