Re: Add prefetch switch stack hook in scheduler function

Nick Piggin
2005-07-28T08:31:57Z

Keith Owens wrote:
> On Thu, 28 Jul 2005 09:41:18 +0200,
> Ingo Molnar <mingo@elte.hu> wrote:

>>i'm wondering, is the switch_stack at the same/similar place as
>>next->thread_info? If yes then we could simply do a
>>prefetch(next->thread_info).
>
>
> No, they can be up to 30K apart. See include/asm-ia64/ptrace.h.
> thread_info is at ~0xda0, depending on the config. The switch_stack
> can be as high as 0x7bd0 in the kernel stack, depending on why the task
> is sleeping.
>

Just a minor point, I agree with David: I'd like it to be called
prefetch_task(), because some architecture may want to prefetch other
memory.

--
SUSE Labs, Novell Inc.

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