On Thu, 2009-10-08 at 16:12 +0530, Arun R Bharadwaj wrote: > > > So cpuidle didn't already have a list of idle functions it takes an > > appropriate one from? > > > > No.. As of now, cpuidle supported only one _set_ of idle states that > can be registered. So in this one set, it would choose the appropriate > idle state. But this list mechanism(actually a stack) allows for > multiple sets. > > This is needed because we have a hierarchy of idle states discovery > in x86. First, select_idle_routine() would select poll/mwait/default/c1e. > It doesn't know of existance of ACPI. Later when ACPI comes up, > it registers a set of routines on top of the earlier set. > > > Then what does this governor do? > > > > The governor would only select the best idle state available from the > set of states which is at the top of the stack. (In the above case, it > would only consider the states registered by ACPI). > > If the top-of-the-stack set of idle states is unregistered, the next > set of states on the stack are considered. > > > Also, does this imply the governor doesn't consider these idle routines? > > > > As i said above, governor would only consider the idle routines which > are at the top of the stack. > > Hope this gave a better idea.. So does it make sense to have a set of sets? Why not integrate them all into one set to be ruled by this governor thing? -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
