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Date: Wed, 06 Sep 2006 22:09:25 +0800
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Subject: sleep for ever ?
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Hi ,
    Take a look at following code :

DECLARE_WAITQUEUE(wait, current);

add_wait_queue(q, &wait);
while (!condition) {
        /* if there is an interrupt here , and the interrupt
           is just the one the sleeping process wait
           for , is this process sleep for the interrupt
           for ever ?*/
        set_current_state(TASK_INTERRUPTIBLE);
        if (signal_pending(current))
                /* handle signal */
        schedule();
}
set_current_state(TASK_RUNNING);
remove_wait_queue(q, &wait);

Suppose the process just want to sleep for an hardware
event , but before the set_current_state() call , the event
come , is the process sleep for ever ?