i386: use the right wrapper to disable the NMI watchdog

When disabled through /proc/sys/kernel/nmi_watchdog, the NMI watchdog uses the
stop() method directly, which does not decrement the activity counter, leading
to a BUG(). Use the wrapper function instead to fix that.

Signed-off-by: Björn Steinbrink <[e-mail]>
Cc: Andi Kleen <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

arch/i386/kernel/cpu/perfctr-watchdog.c

···
 	void (*unreserve)(void);
 	int (*setup)(unsigned nmi_hz);
 	void (*rearm)(struct nmi_watchdog_ctlblk *wd, unsigned nmi_hz);
-	void (*stop)(void *);
+	void (*stop)(void);
 	unsigned perfctr;
 	unsigned evntsel;
 	u64 checkbit;
···
 	if (atomic_read(&nmi_active) <= 0)
 		return;
 
-	on_each_cpu(wd_ops->stop, NULL, 0, 1);
+	on_each_cpu(stop_apic_nmi_watchdog, NULL, 0, 1);
 	wd_ops->unreserve();
 
 	BUG_ON(atomic_read(&nmi_active) != 0);
···
 	return 1;
 }
 
-static void single_msr_stop_watchdog(void *arg)
+static void single_msr_stop_watchdog(void)
 {
 	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);
 
···
 	return 1;
 }
 
-static void stop_p4_watchdog(void *arg)
+static void stop_p4_watchdog(void)
 {
 	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);
 	wrmsr(wd->cccr_msr, 0, 0);
···
 void lapic_watchdog_stop(void)
 {
 	if (wd_ops)
-		wd_ops->stop(NULL);
+		wd_ops->stop();
 }
 
 unsigned lapic_adjust_nmi_hz(unsigned hz)