On Fri, 28 May 2010, Rafael J. Wysocki wrote: > > And the forced-suspend design relies on the fact that processes remain > > frozen throughout. If we leave some processes unfrozen and one of them > > somehow becomes runnable, that means we have to abort the forced > > suspend before the process is allowed to run. > > We could avoid that if drivers could block tasks, but there are questions to > answer. First off, how a driver is supposed to know when to block the task > using it and when to do its power management transparently for the task? > Second, how to intercept and block all possible interfaces that user space > can use to talk to drivers (how to intercept a task using mmapped device, for > example)? We talked about this a few years ago and decided it was not feasible. It would require substantial changes to every device driver. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
