x86: traps_xx: modify default_do_nmi

 - local caching of smp_processor_id() in default_do_nmi()
 - v2: do not split default_do_nmi over two lines

On Wed, Jul 02, 2008 at 08:12:20PM +0400, Cyrill Gorcunov wrote:
> | -static notrace __kprobes void default_do_nmi(struct pt_regs *regs)
> | +static notrace __kprobes void
> | +default_do_nmi(struct pt_regs *regs)
> | [ ... ]
> | -asmlinkage notrace  __kprobes void default_do_nmi(struct pt_regs *regs)
> | +asmlinkage notrace __kprobes void
> | +default_do_nmi(struct pt_regs *regs)
>
> Hi Alexander, good done, thanks! But why did you split default_do_nmi
> definition by two lines? I think it would be better to keep them as it
> was before, ie by a single line
>
> 	static notrace __kprobes void default_do_nmi(struct pt_regs *regs)

Thanks! Here is the replacement patch with default_do_nmi left on
a single line.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Acked-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/traps_32.c

@@ -789,9 +789,12 @@ void notrace __kprobes die_nmi(char *str, struct pt_regs *regs, int do_panic)
 static notrace __kprobes void default_do_nmi(struct pt_regs *regs)
 {
 	unsigned char reason = 0;
+	int cpu;
+
+	cpu = smp_processor_id();
 
-	/* Only the BSP gets external NMIs from the system: */
-	if (!smp_processor_id())
+	/* Only the BSP gets external NMIs from the system. */
+	if (!cpu)
 		reason = get_nmi_reason();
 
 	if (!(reason & 0xc0)) {
@@ -805,7 +808,7 @@ static notrace __kprobes void default_do_nmi(struct pt_regs *regs)
 		 */
 		if (nmi_watchdog_tick(regs, reason))
 			return;
-		if (!do_nmi_callback(regs, smp_processor_id()))
+		if (!do_nmi_callback(regs, cpu))
 			unknown_nmi_error(reason, regs);
 #else
 		unknown_nmi_error(reason, regs);

arch/x86/kernel/traps_64.c

@@ -827,7 +827,7 @@ unknown_nmi_error(unsigned char reason, struct pt_regs * regs)
 
 /* Runs on IST stack. This code must keep interrupts off all the time.
    Nested NMIs are prevented by the CPU. */
-asmlinkage notrace  __kprobes void default_do_nmi(struct pt_regs *regs)
+asmlinkage notrace __kprobes void default_do_nmi(struct pt_regs *regs)
 {
 	unsigned char reason = 0;
 	int cpu;