Subject: Re: Interrupt starvation points
From: Daniel Walker <dwalker@mvista.com>
Reply-To: dwalker@mvista.com
To: Ingo Molnar <mingo@elte.hu>
Cc: linux-kernel@vger.kernel.org
In-Reply-To: <20050211173025.GA17387@elte.hu>
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	 <20050211173025.GA17387@elte.hu>
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Date: 11 Feb 2005 09:36:42 -0800
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On Fri, 2005-02-11 at 09:30, Ingo Molnar wrote:
> 
> i'm wondering what the best approach would be. Right now if
> DIRECT_PREEMPT is enabled [it's disabled currently] and a higher-prio
> task has been woken up we switch to it without ever enabling interrupts
> again. Re-enabling interrupts during schedule() will reduce irq
> latencies but will lengthen critical sections.


	Yeah, it's a trade off .. The longest points that I observed involved
kernel threads like desched . Things that the scheduler() regularly
wakes up anyways. I would imagine there is an upper bound on the number
of tasks the scheduler can wake up.

Daniel

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