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Date: Thu, 5 Feb 2009 01:28:37 +0300
Message-ID: <f19298770902041428m6a23846fud8cfba8bb3deab4@mail.gmail.com>
Subject: Re: [git pull] scheduler fixes
From: Alexey Zaytsev <alexey.zaytsev@gmail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: 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>
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On Mon, Feb 2, 2009 at 12:52, 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.
>
> Which suggests that an initial preempt_count offset of 1 should suffice
> to fix this issue and not confuse the softirq tracing, hmm?

Can't we just copy the preempt count when switching stacks?