On Thu, Aug 05, 2010 at 06:18:42AM -0700, david@xxxxxxx wrote: > On Wed, 4 Aug 2010, Paul E. McKenney wrote: > > >Continuing to rush in where angels fear to tread... > > here here :-) > > >o "PM-driving application" are applications that are permitted > > to acquire suspend blockers on Android. Verion 8 of the > > suspend-blocker patch seems to use group permissions to determine > > which applications are classified as power aware. More generally, > > PM-driving applications seem to be those that have permission > > to exert some control over the system's sleep state. > > > > Note that an application might be power-oblivious on one Android > > device and PM-driving on another, depending on whether the user > > allows that application to acquire suspend blockers. The > > classification might even change over time. For example, a > > user might give an application PM-driving status initially, > > but change his or her mind after some experience with that > > application. > > One thing that I think it's important to document here is > theinformation that Brian provided in response to your question > about how many (or actually how few) applications fall into this > catefory Agreed!!! I have added this, and it will appear in the next version. Thanx, Paul > David Lang > > Quote: > > >I should have asked this earlier... What exactly are the apps' > >compatibility constraints? Source-level APIs? Byte-code class-library > >invocations? C/C++ dynamic linking? C/C++ static linking (in other > >words, syscall)? > > For Java/Dalvik apps, the wakelock API is pertty high level -- it > talks to a service via RPC (Binder) that actually interacts with the > kernel. Changing the basic kernel<->userspace interface (within > reason) is not unthinkable. For example, Arve's suspend_blocker patch > provides a device interface rather than the proc interface the older > wakelock patches use. We'd have to make some userspace changes to > support that but they're pretty low level and minor. > > In the current model, only a few processes need to specifically > interact with the kernel (the power management service in the > system_server, possibly the media_server and the radio interface > glue). A model where every process needs to have a bunch of > instrumentation is not very desirable from our point of view. We > definitely do need reasonable statistics in order to enable debugging > and to enable reporting to endusers (through the Battery Usage UI) > what's keeping the device awake. > > Brian > _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
