Re: [PATCH] pcmcia event thread. (fwd)

[Jeff Garzik <jgarzik@mandrakesoft.com>]

David Woodhouse wrote:
> jgarzik@mandrakesoft.com said:
> > In any case, we -really- need a wait_for_kernel_thread_to_die()
> > function.
> 
> up_and_exit() would do it. Or preferably passing the address of the
> semaphore as an extra argument to kernel_thread() in the first place.

Any solution which involves a function being called from a kernel
thread, and/or passing another arg to a kernel thread, is a non-starter
...  See the discussion about timer_exit() a while ago.  This sort of
thing should be done at a higher level.  Not only does that eliminate
any possibility of a race between thread function calling
MOD_DEC_USE_COUNT/up_and_exit and module unload, but it also allows us
to more easily implement wait_for_kernel_thread_to_die() without having
to do silly stuff like pass extra args to threads (...modifying the
thread API in the process).

IMHO it is possible to solve this in a generic way without having to
change the code for every single kernel thread.


Thanks for all the explanation, I think I now understand all the stuff
your kernel thread is doing.  Your solution sounds like a decent
solution for the problem described.  I have not looked at the socket
driver code observe parse_events() usage, so I cannot say whether your
problem description is accurate however :)

	Jeff


-- 
Jeff Garzik             |
Building 1024           | The chief enemy of creativity is "good" sense
MandrakeSoft            |          -- Picasso
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