Re: SMP share data declaration

[Jesper Juhl]

On 14/07/06, wyb@xxxxxxxxxxxxx <wyb@xxxxxxxxxxxxx> wrote:
> I know that an integer variable should be declared volatile to share between
> CPUs.

NO. volatile won't protect you sufficiently.

Use spinlocks, mutexes, semaphores, barriers and the like to protect
variables from concurrent access. Using volatile for this is a BUG and
it won't work correctly.


--
Jesper Juhl <jesper.juhl@xxxxxxxxx>
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