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Date: Sat, 31 Jan 2009 21:21:06 +0000
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Alexey Zaytsev <alexey.zaytsev@gmail.com>, Ingo Molnar <mingo@elte.hu>,
       Linus Torvalds <torvalds@linux-foundation.org>,
       linux-kernel@vger.kernel.org, Andrew Morton <akpm@linux-foundation.org>,
       Nick Piggin <npiggin@suse.de>
Subject: Re: [git pull] scheduler fixes
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On Sat, 31 Jan 2009 19:08:47 +0100
Peter Zijlstra <peterz@infradead.org> wrote:

> On Sat, 2009-01-31 at 20:49 +0300, Alexey Zaytsev wrote:
> > 
> > And answering an earlier question, this happens only on i386 and only
> > with 4K stacks because x86_64 dosn't have a separate softirq stack,
> > so the preempt count diring the soft irq is at least IRQ_EXIT_OFFSET.
> 
> What do the other 30 odd architectures that Linux supports do? Is i386
> 4k really the _only_ with separate softirq stacks?

x86-64 and some of the other platforms could do with IRQ stacks but that
is another story.