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Subject: Re: interrupt - spin lock question
From: Robert Love <rml@tech9.net>
To: sridharv@ufl.edu
Cc: linux-kernel@vger.kernel.org
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Date: 04 Mar 2002 02:19:09 -0500
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On Mon, 2002-03-04 at 01:33, sridharv@ufl.edu wrote:

> ok things are clear now. so the spin_lock_irq friends are actually for 2 
> purposes - preventing racing from interrupts and from SMP. so if SMP is not 
> chosen only the local_irq_disable() part works right??
> 
> do { local_irq_disable();         spin_lock(lock); } while (0)

Correct.  Although, you would want to use spin_lock_irqsave most of the
time, not spin_lock_irq (difference is, the stored flags value is used
to restore interrupts to there previous condition instead of
unconditionally reenable them).

Btw, Go Gators!

	Robert Love

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