[dpdk-dev] [PATCH v9 04/10] ethdev: add simple power management API

[Thomas Monjalon]

27/10/2020 12:15, Liang, Ma:
> > > --- a/lib/librte_ethdev/rte_ethdev.h
> > > +++ b/lib/librte_ethdev/rte_ethdev.h
> > > +/**
> > > + * Retrieve the wake up address for the receive queue.
> > 
> > I guess how this function should be used,
> > but a bit more explanations would not hurt here.
> agree
> > > + *
> > > + * @param port_id
> > > + *   The port identifier of the Ethernet device.
> > > + * @param queue_id
> > > + *   The Rx queue on the Ethernet device for which information will be
> > > + *   retrieved.
> > > + * @param wake_addr
> > > + *   The pointer to the address which will be monitored.
> > 
> > This function does not make the address monitored, right?
> This function only get the target wakeup address. that does not monitor this address.
> > 
> > > + * @param expected
> > > + *   The pointer to value to be expected when descriptor is set.
> > 
> > Not sure we should restrict it to a "descriptor".
>   actully that is not limited to a descriptor, any writeback content should work.
> > 
> > Expecting a value or some bits looks too much restrictive.
> > I understand it probably fits well for Intel NICs,
> > but in the general case, we can imagine that any change
> > in a byte array could be a wake up signal.
> 
> this parameter doesn not limited user how to use it.
> In fact, current design can support any bits change within 64 bits content.

How the driver can specify that any value change should be monitored?
I understand that it is only a value/mask pair,
it does not give room for "any value".