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From: Laurent Pinchart <laurentp@cse-semaphore.com>
To: linuxppc-embedded@ozlabs.org
Subject: Re: basic and stupid question on wait_event and wake_up
Date: Mon, 13 Aug 2007 11:30:11 +0200
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On Monday 13 August 2007 11:22, Ming Liu wrote:
> Dear Momen,
> OK. I see now. So you mean condition is only to judge whether a sleeping
> process could be waken up or not when wake_up() is executed in other
> processes or interrupt handlers. What really wakes the process up is still
> the function of wake_up, right? We just execute wake_up() and then check if
> condition is true. If yes, the process will leave its sleeping and wake up;
> if not, it keep sleeping. Am I right?

Actually, the process will wake up every time you call wake_up(). It will then 
evaluate the condition. If the condition is true, the process will return 
from wait_event. If the condition is false, it will go back to sleep.

Best regards,

Laurent Pinchart