Re: [PATCH] Only process_die notifier in ia64_do_page_fault if KPROBES is configured.

Andi Kleen
2005-08-30T23:38:19Z

On Wednesday 31 August 2005 01:05, Luck, Tony wrote:
> >Please do not generate any code if the feature cannot ever be
> >used (CONFIG_KPROBES off). With this patch we still have lots of
> >unnecessary code being executed on each page fault.
>
> I can (eventually) wrap this call inside the #ifdef CONFIG_KPROBES.

At least the original die notifiers were designed as a generic debugger
interface, not a kprobes specific thing. So I don't think it's a good idea.
Given most debuggers don't need the early page fault hook and it's
mostly needed for a special case in kprobes, but it doesn't seem nice to only
offer a subset of the hooks with specific config options.

Also with the inline the test should be essentially a single test of
a global variable and jump. Hardly a big performance issue, no?

-Andi