From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Molnar <mingo@elte.hu>
Date: Mon, 21 Jan 2002 20:32:28 +0000
Subject: Re: [Linux-ia64] Help with Ingo scheduler on IA64
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To: linux-ia64@vger.kernel.org

On Mon, 21 Jan 2002, Erich Focht wrote:

> Unfortunately the context switch in Ingo's scheduler happens with the
> runqueue lock held, which can lead to a deadlock eg. if the timer
> interrupt is called inside and sched_tick spinlocks on the runqueue
> lock held by schedule(). On IA64 (HZ24) this probably happens much
> more frequently than on IA32 (HZ0).

we call context_switch() with irqs disabled. The ia64 version of
switch_to() should not re-enable IRQs or it will deadlock.

	Ingo