Re: [Linux-ia64] Help with Ingo scheduler on IA64

Ingo Molnar
2002-01-21T22:11:49Z

On Mon, 21 Jan 2002, David Mosberger wrote:

> Ingo> we call context_switch() with irqs disabled. The ia64 version
> Ingo> of switch_to() should not re-enable IRQs or it will deadlock.
>
> The existing switch_to() enables interrupts if the new task's stack is
> on a different (kernel-) page.

oh, i see. Why were irqs enabled explicitly? The old scheduler called
switch_to() with irqs enabled, all the time.

> [...] If the new scheduler guarantees to call switch_to() with irqs
> disabled, we can simply drop the relevant code.

yes. And this should fix the lockup as well.

Ingo