Am Mittwoch, 13. Februar 2008 schrieb Karsten Wiese:
>
> ITDs can be detached from urbs, before the active frame elapses. Now those
> ITDs are immediately recycled.
> If the ITD is reused then, transactions based on its new usage can already
> happen while the frame is still active, too early.
Hi Dave,
your patch that moves ITD-recycling past URB-completion solves the
"common case": completion callback resubmits urb.
It misses
a) client driver delays urb resubmission past completion callback.
I only know my us122l driver doing this.
b) stream stops midframe: ITDs are put back into the dma_pool.
Things go wrong, if another urb_submit() picks up the ITD that has just
been recycled from a still active frame.
This will happen once an ehci client driver starts using uframe precise
scheduling.
Hmm?
Karsten
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