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Subject: Re: [git pull] scheduler fixes
From: Peter Zijlstra <peterz@infradead.org>
To: Alexey Zaytsev <alexey.zaytsev@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>,
       Linus Torvalds <torvalds@linux-foundation.org>,
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       Nick Piggin <npiggin@suse.de>
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Date: Sat, 31 Jan 2009 19:08:47 +0100
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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?