Darren New <dne### [at] sanrrcom> wrote:
> I always wondered why nobody makes a CPU with a non-privileged instruction 
> that says something like "turn off interrupts for the next N instructions", 
> where N < 8 or so. Then you wouldn't need "test-and-set" or atomic writes or 
> any of that sort of specialized instructions.

> Of course, I guess the time for that idea has come and gone with the rise of 
> multicore machines where interrupts aren't the only thing you have to lock.

  I think it would cause security problems if a userland program could turn
off interrupts, even if for a limited period of time.

  Besides, most/all CPU designs (especially Intel's) have always supported
multiprocessor setups, so having to support true multitasking has always
been there.

-- 
                                                          - Warp

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