Hi! > > There are two things I believe. There's a generic issue with usermode > > helpers that make no sense to call between pre-suspend and > > post-resume, and there's the specific issue of adding/removing > > devices. > > > > I believe that "bus" drivers such as USB should indeed get a first > > round of notifications to tell them to stop performing bus > > plug/unplug operations (it's debatable whether we want to keep unplug > > going provided we can stack up the usermode events and re-send them > > later though, but let's say no for the sake of simplicity). > > Yes. Rafael, how close is your new notifier chain to mainline? Can it > at least be added to Greg KH's development tree so that I can start > using it? It should be in -mm, IIRC. > > I think it's a fairly significant change from the current freezer and I > > also think it's a very good idea. The more I think about it, the more I > > like it, in the sense that it's a simple drop-in that you could put in a > > lot of the ioctl path of drivers to just block tasks that are trying to > > call in while suspending, and could be used selectively by things like > > the USB hub threads. > > That's what I had in mind. Rafael, can we add an "icebox" routine? > Like Ben says, it doesn't need to be much more than a waitqueue > that the current task puts itself on if a suspend is in progress. > Callers arriving at a time when the icebox isn't activated should > simply return without blocking. Basically the icebox should be active > at the same times as the existing freezer. You could use try_to_freeze(), but you want it to be separate routine so it can be grepped for... Can you #define icebox_me try_to_freeze for testing? Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
