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Date: Mon,  4 Mar 2002 01:33:30 -0500
From: sridharv@ufl.edu
To: linux-kernel@vger.kernel.org
Subject: Re: interrupt - spin lock question
In-Reply-To: <1015219129.3c8303b9e87a7@webmail.health.ufl.edu> <1015219669.868.35.camel@phantasy>
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> Right, that is why you would use a spin_lock ! :)
> 
> Further, you would want to use a spin_lock_irq and related friends.  The
> irq disable prevents the race wrt interrupts and the spin_lock prevents
> racing wrt SMP.
> 

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)

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