[PATCH] i386: Add SMP support on i386 to reservation framework

This patch includes the changes to make the nmi watchdog on i386 SMP aware.
A bunch of code was moved around to make it simpler to read.  In addition,
it is now possible to determine if a particular NMI was the result of the
watchdog or not.  This feature allows the kernel to filter out unknown NMIs
easier.
Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Andi Kleen <ak@suse.de>

arch/i386/kernel/apic.c

@@ -586,8 +586,7 @@ void __devinit setup_local_APIC(void)
 			printk("No ESR for 82489DX.\n");
 	}
 
-	if (nmi_watchdog == NMI_LOCAL_APIC)
-		setup_apic_nmi_watchdog();
+	setup_apic_nmi_watchdog(NULL);
 	apic_pm_activate();
 }
 

arch/i386/kernel/traps.c

@@ -724,7 +724,7 @@ static void default_do_nmi(struct pt_regs * regs)
 		 * so it must be the NMI watchdog.
 		 */
 		if (nmi_watchdog) {
-			nmi_watchdog_tick(regs);
+			nmi_watchdog_tick(regs, reason);
 			return;
 		}
 #endif

arch/i386/oprofile/nmi_timer_int.c

@@ -42,9 +42,7 @@ static void timer_stop(void)
 
 int __init op_nmi_timer_init(struct oprofile_operations * ops)
 {
-	extern int nmi_active;
-
-	if (nmi_active <= 0)
+	if (atomic_read(&nmi_active) <= 0)
 		return -ENODEV;
 
 	ops->start = timer_start;

include/asm-i386/nmi.h

@@ -32,13 +32,14 @@ extern void release_perfctr_nmi(unsigned int);
 extern int reserve_evntsel_nmi(unsigned int);
 extern void release_evntsel_nmi(unsigned int);
 
-extern void setup_apic_nmi_watchdog (void);
+extern void setup_apic_nmi_watchdog (void *);
 extern int reserve_lapic_nmi(void);
 extern void release_lapic_nmi(void);
 extern void disable_timer_nmi_watchdog(void);
 extern void enable_timer_nmi_watchdog(void);
-extern void nmi_watchdog_tick (struct pt_regs * regs);
+extern void nmi_watchdog_tick (struct pt_regs * regs, unsigned reason);
 
+extern atomic_t nmi_active;
 extern unsigned int nmi_watchdog;
 #define NMI_DEFAULT     -1
 #define NMI_NONE	0