Re: [ham] Re: Gracefully killing kswapd, or any kernel thread

["linux-os \(Dick Johnson\)" <linux-os@analogic.com>]

On Fri, 9 Sep 2005, Kristis Makris wrote:

> On Wed, 2005-09-07 at 18:36 -0400, linux-os (Dick Johnson) wrote:
>> On Wed, 7 Sep 2005, Kristis Makris wrote:
>>
>>>> To kill a kernel thread, you need to make __it__ call exit(). It must be
>
> I was able to make it call do_exit(). However, even if I recompile a
> kernel to have kswapd issued a do_exit(), I still see from ps:
>
> root         4  0.0  0.0     0    0 ?        Z    06:20   0:00 [kswapd
> <defunct>]
>
> Why isn't the task_struct for it gone ?
>

Because it's now defunct <Z>, a zombie, waiting for somebody to
reap its return status. You are almost there, you need to issue
the kernel equivalent of waitpid() (sys_waitpid) to grab that
status and throw it away. That's what the code I showed you
did when it would shut down and remove a module that had
a kernel thread.

Cheers,
Dick Johnson
Penguin : Linux version 2.6.13 on an i686 machine (5589.53 BogoMips).
Warning : 98.36% of all statistics are fiction.
.
I apologize for the following. I tried to kill it with the above dot :

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