On Fri, 1 Oct 2010, Rafael J. Wysocki wrote: > > > In my opinion the _irq operations should really be one-shot, without > > > any looping, waking up parents etc. I mean, if the parent is not RPM_ACTIVE, > > > the _irq resume should immediately fail and analogously for the _irq > > > suspend. And so on. As simple as reasonably possible. > > > > But what if the device's own status is currently SUSPENDING or > > RESUMING? Do you want to fail when that happens, instead of waiting > > for the concurrent operation to finish? > > Yes. IMO an _irq() suspend should only be allowed if the status is RPM_ACTIVE > and an _irq() resume should fail if the status is not RPM_SUSPENDED. The > error code returned should depend on the situation, though. > > > There's no way to prevent this > > on SMP systems, because a wakeup request can arrive while a > > software-initiated resume is in progress. > > I know that. :-) I suspect Kevin will not want to live with this restriction, but I'd like to hear from him. Kevin? > > What you are describing is basically what autosuspend was intended to > > accomplish (that is, formalizing the difference between "the device > > just became idle, you should consider when to suspend it" and "the > > device has been idle for a sufficiently long time, please suspend it > > now"). Would the r8169 driver be simplified if it used autosuspend? > > At the moment it suspends when the network cable is removed from the device > and the hack I mentioned is used during the resume after the cable has been > reinserted (it checks if the cable is still there and schedules suspend if not). That does seem like a strange hack. Instead of scheduling a suspend, why not simply do a suspend as soon as you learn that the cable has been removed again? Is there a problem about the connection status bouncing? > If we removed the immediate idle notification after a successful resume, it > might need to be reworked slightly. My suggestion was that we remove the idle notification after a failed suspend, not the notification after a successful resume. Alan Stern _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
