Am Freitag, 30. März 2007 10:39 schrieb Greg KH:
> > To solve this with locking would require both CPU A and CPU B to take
> > the lock, which means that the urb would have to be submitted with
> > GFP_ATOMIC.
>
> Can't this all be solved with a simple:
>
> get port spinlock
> a = urb->status
> write_busy = 0
> unlock spinlock
>
> In the callback, and in the write path:
>
> get port spinlock
> if write_busy
> unlock
> exit
> write_busy = 1
> unlock port spinlock
> submit_urb
>
Oops. You are right. That would work.
If you think that's simpler, yes it can be done.
Regards
Oliver
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