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Subject: Re: question on spinlocks
From: Robert Love <rml@tech9.net>
To: Oliver Neukum <oliver@neukum.name>
Cc: Thunder from the hill <thunder@lightweight.ods.org>,
       Ralf Baechle <ralf@uni-koblenz.de>, linux-kernel@vger.kernel.org
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	<200209020002.41381.oliver@neukum.name>
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On Sun, 2002-09-01 at 18:02, Oliver Neukum wrote:
> 
> > > No; spin_lock_irqsave/spin_unlock_irqrestore and spin_lock/spin_unlock
> > > have to be used in matching pairs.
> >
> > If it was his least problem! He'll run straight into a "schedule w/IRQs
> > disabled" bug.
> 
> OK, how do I drop an irqsave spinlock if I don't have flags?

See my previous message.

Do not do what you are trying to do.  Dropping a lock and calling
schedule is fine.  Ditto with the interrupt part.

But note:

	- interrupts will be reenabled when you reschedule and still
	  enabled when your task is finally running again.

	- Since interrupts are going to magically restore, if you are
	  worried about the state of interrupts previous to your
	  function... you have a problem.

OK?

	Robert Love

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