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<P><FONT SIZE=2>Hi,<BR>
<BR>
I had asked a similar question before, but I've some doubts regarding the correctness of the following code. Please see the following code snippet from the file linux-2.6.37/arch/x86/kernel/apm_32.c. This is the core function of apm thread.<BR>
<BR>
<BR>
Question:<BR>
Suppose the apm thread has just completed execution of the line 1442 and the scheduling happens for some reason, AFAIK, since the apm thread's state has been set to TASK_INTERRUPTIBLE, it will be removed from the run-queue. So there is a chance for the apm thread to remain suspended indefinitely as nobody is there to wakeup the apm thread, correct?<BR>
<BR>
I'm asking this because the same function has been given as an example in the following link and would like to confirm the accuracy of the example.<BR>
<BR>
<A HREF="http://www.linuxjournal.com/node/8144/print">http://www.linuxjournal.com/node/8144/print</A><BR>
<BR>
<BR>
<BR>
1437 static void apm_mainloop(void)<BR>
1438 {<BR>
1439 DECLARE_WAITQUEUE(wait, current);<BR>
1440<BR>
1441 add_wait_queue(&apm_waitqueue, &wait);<BR>
1442 set_current_state(TASK_INTERRUPTIBLE);<BR>
1443 for (;;) {<BR>
1444 schedule_timeout(APM_CHECK_TIMEOUT);<BR>
1445 if (kthread_should_stop())<BR>
1446 break;<BR>
1447 /*<BR>
1448 * Ok, check all events, check for idle (and mark us sleeping<BR>
1449 * so as not to count towards the load average)..<BR>
1450 */<BR>
1451 set_current_state(TASK_INTERRUPTIBLE);<BR>
1452 apm_event_handler();<BR>
1453 }<BR>
1454 remove_wait_queue(&apm_waitqueue, &wait);<BR>
1455 }<BR>
<BR>
<BR>
--<BR>
Thanks,<BR>
Sudheer<BR>
<BR>
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