Re: What does atomic_read actually do?

From: Arjan van de Ven
Date: Sat Dec 18 2004 - 14:58:42 EST


On Sat, 2004-12-18 at 14:20 -0500, Joseph Seigh wrote:
> I mean atomic in the either old or new sense. I'm wondering what
> guarantees
> the atomicity. Not the C standard. I can see the gcc compiler uses a MOV
> instruction to load the atomic_t from memory which is guaranteed atomic by
> the architecture if aligned properly. But gcc does that for any old int
> as far as I can see, so why use atomic_read?

it does so on *x86*.
On other architectures, something else might be needed..

also it makes the api more symetric as well.



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