[PATCHv2 6/7] x86: traps_xx: modify default_do_nmi

Alexander van Heukelum
2008-07-02T16:41:25Z

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

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>

---

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. Patch 7 applies with 1 line fuzz.

Greetings,
Alexander

> - Cyrill -

diff --git a/arch/x86/kernel/traps_32.c b/arch/x86/kernel/traps_32.c
index bed6e72..9e3b0c4 100644
--- a/arch/x86/kernel/traps_32.c
+++ b/arch/x86/kernel/traps_32.c
@@ -793,9 +793,12 @@ 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)) {
@@ -809,7 +812,7 @@ 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);
diff --git a/arch/x86/kernel/traps_64.c b/arch/x86/kernel/traps_64.c
index 7511553..26ab0be 100644
--- a/arch/x86/kernel/traps_64.c
+++ b/arch/x86/kernel/traps_64.c
@@ -832,7 +832,7 @@ 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;