On Thu, Jul 22, 2004 at 11:49:27 +0530, RSudharsanan@xxxxxxxxxxxxxx wrote: > > hi, > thanks to Jan for the help it worked fine i was really confused with > many data structures waitiqueue/wokqueue/taskqueue.Now I am able to create > threads.But i have some more doubts > > *How shall i kill the thread i created with kernel_thread > I tried using > send_sig(SIGKILL,thread_task,1); > thread_task i am initialising with > thread_task = current ; > when the thread starts.Is it the right way of killing the thread. > But even after killing i find the thread as <defunct> with the ps viewer > under the application using the driver. Especialy for modules, you must make sure the thread has exited before you return from module_done(). And there is only one way to do it -- use complete_and_exit() to end the thread and wait_for_completion() in module_dome(). That means, that the thread must exit actively. Now the question comes down to how to tell the thread to exit. There are generaly two ways: 1) Have a flag somewhere. Wake up the thread (by setting it's state to running or using a waitqueue) and have it check that flag and complete_and_exit() if it's set. 2) Use a signal. You can send the thread a signal and it will cause it to wake up from interruptible sleep automaticaly. But you must check signal_pending() yourself and complete_and_exit() if appropriate bit is set. Normaly, signals are handled during return to userspace, but kernel threads never return to userspace. Thus you have to check for them manualy. ------------------------------------------------------------------------------- Jan 'Bulb' Hudec <bulb@xxxxxx>
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