Re: [PATCH v2 x86 1/2] fix page faults by nmiaction in nmi if kmemcheck is enabled

Don Zickus
2012-03-05T21:46:32Z

On Mon, Mar 05, 2012 at 06:49:07PM +0100, Peter Zijlstra wrote:
> On Mon, 2012-03-05 at 18:05 +0800, Li Zhong wrote:
> > +static struct nmiaction arch_trigger_all_cpu_bt_nmiaction = {
> > + .handler = arch_trigger_all_cpu_backtrace_handler,
> > + .name = "arch_bt",
> > +};
> > +
> > static int __init register_trigger_all_cpu_backtrace(void)
> > {
> > - register_nmi_handler(NMI_LOCAL, arch_trigger_all_cpu_backtrace_handler,
> > - 0, "arch_bt");
> > + register_nmi_handler(NMI_LOCAL, &arch_trigger_all_cpu_bt_nmiaction);
> > return 0;
> > }
>
> If you look at things like cpu_notifier() you can shorten this still:
>
> #define nmi_notifier(t, fn, n) \
> do { \
> static struct nmiaction fn##_na = { \
> .handler = (fn), \
> .name = (n), \
> }; \
> register_nmi_handler((t), &fn##_na); \
> } while (0)
>
> The whole thing then becomes:
>
> nmi_notifier(NMI_LOCAL, arch_trigger_all_cpu_backtrace_handler, "arch_bt");

Hi Li,

I would be open to this suggestion. If you want to modify the patch for
this approach.

Cheers,
Don