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

[Samuel Thibault]

Andi Kleen, le Fri 22 May 2009 23:59:39 +0200, a écrit :
> > > - You got bus master DMA in your test machine?
> > 
> > That's not related to the LOCK_PREFIX concern, which is about the
> > processor only, not interaction with other devices.
> 
> Actually it's related to other devices; but only very few (most MMIO
> doesn't support atomic cycles and is uncached anyways). But there's no driver 
> for real hardware in Linux that relies on it to my knowledge.

That's what I meant: AIUI, LOCK_PREFIX has always only been used for
inter-processor interaction (atomic variables, spinlocks, etc.), not for
processor-device interaction.

Samuel
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