Re: [block IO crash] Re: 2.6.39-rc5-git2 boot crashs

From: Linus Torvalds
Date: Wed May 04 2011 - 15:45:52 EST


On Wed, May 4, 2011 at 12:30 PM, Christoph Lameter <cl@xxxxxxxxx> wrote:
>
> The naming convention came about from the existing this_cpu_xxx
> operations

You're missing my point.

An "add" operation makes sense even if it isn't atomic, because
atomicity isn't a part of the definition of "add".

But cmpxchg DOES NOT MAKE SENSE without atomicity guarantees.

The whole operation is about atomicity.

Having a version that isn't atomic is STUPID. It's misleading. It's _wrong_.

In contrast, having a non-atomic "add" version is understandable.

So when you say "naming convention", you're missing the much bigger
naming convention. Namely the "cmpxchg" part!

Linus
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