Re: [BUG FIX] Make x86_32 uni-processor Atomic ops, Atomic

From: Michael S. Zick
Date: Fri May 22 2009 - 15:00:57 EST


On Fri May 22 2009, you wrote:
> "Michael S. Zick" <lkml@xxxxxxxxxxxx> writes:
>
> > Found in the bit-rot for 32-bit, x86, Uni-processor builds:
>
> Actually uni processor should not use the lock prefix
> because it doesn't need it; the only exception are some special
> ops used in para-virtualization which are special cased.
>

Unless you have interrupts enabled, then you have two contexts.
Only xchg is "naturally" atomic.

Mike
> -Andi
>


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