Re: [BUG] Variable stopmachine_state should be volatile

Hi!

> The model to access variable stopmachine_state is that a main thread
> writes it and other threads read it. Its declaration has no sign
> volatile. In the while loop in function stopmachine, this variable is
> read, and compiler might optimize it by reading it once before the loop
> and not reading it again in the loop, so the thread might enter dead
> loop.

No. volatile may look like a solution, but it usually is not. You may
need some barriers, atomic_t or locking.
								Pavel
-- 
Thanks, Sharp!
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• References:
  • [BUG] Variable stopmachine_state should be volatile
    • From: "Zhang, Yanmin" <[email protected]>

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