On Tuesday, 3 July 2007 16:21, Johannes Berg wrote: > On Tue, 2007-07-03 at 14:56 +0200, Rafael J. Wysocki wrote: > > > Still, can you please read this post from Alan Stern: > > > > https://lists.linux-foundation.org/pipermail/linux-pm/2007-June/012847.html > > > > ? I don't think I'm able to repeat the arguments given in there in a > > convincing way. > > As I read it, Alan basically has two objections: > (1) drivers shouldn't need to worry about this > (2) suspend should be transparent to userspace > > His proposed solution (freezing tasks when they cross the kernel > boundary) helps for the s-t-r case, but in fact doesn't solve (1) > because devices can be suspended at runtime This is a different thing and a different infrastructure is needed for it (not present at the moment). > and then you certainly do not want to freeze tasks that try to access the > device. > > (2) is related but not identical, what if you have a device suspended at > runtime and some tasks tries to access it; should the task block until > you wake up that device? I think the device should be woken up in that case. > I think the core of the discussion isn't appreciated by everybody here > yet---we need to solve both run-time and suspend-to-ram-time device > suspend, not just one of them. For now, we're discussing the suspend-to-ram-time suspend only, for which we have (some) infrastrcuture (and which should be supported by all drivers, IMO). Greetings, Rafael -- "Premature optimization is the root of all evil." - Donald Knuth _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
