Re: msleep() on recursivly locked mutexes

On Friday 27 April 2007 02:32:20 pm Hans Petter Selasky wrote:
P0 unlock(1);
P0 unlock(2);

this looks "interesting".
Can you give a more concrete example of this?
what work is done in the upcall? WHo is upcalling to who?

For example an USB device driver might be up-calling to the USB host
controller driver. Down call is when the transfer finishes.

I think in this case you don't want to keep the periph locked while you ask
the controller to process requests. Instead, the periph drivers should queue
requests to the controller and receive replies, but they should be considered
as two independent objects. For example, network drivers drop their lock
when passing a packet (request) up the stack.

--
John Baldwin
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