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Date: Mon, 28 Jan 2002 20:21:56 +0100 (CET)
From: Ingo Molnar <mingo@elte.hu>
Reply-To: <mingo@elte.hu>
To: Martin Josefsson <gandalf@wlug.westbo.se>
Cc: Linus Torvalds <torvalds@transmeta.com>,
        linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [patch] [sched] yield speedup, 2.5.3-pre5
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On Mon, 28 Jan 2002, Martin Josefsson wrote:

> > -	spin_unlock_irq(&rq->lock);
> > +	spin_unlock(&rq->lock);

> I'm not an spinlock expert but shouldn't you use spin_unlock_irq()
> when it was locked with spin_lock_irq() ?

normally yes, but in this case it's an optimization: schedule() will
disable interrupts within a few cycles, so there is no point in enabling
irqs for a short amount of time.

	Ingo

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