Hello Jacob, Srinivas, On Wed, Nov 04, 2015 at 09:05:52AM -0800, Srinivas Pandruvada wrote: > On Wed, 2015-11-04 at 08:58 -0800, Jacob Pan wrote:
<cut> > > > > I have two choices for this code: > > > > 1) be part of existing powerclamp driver but require exporting some > > > > sched APIs. > > > > 2) be part of sched since the genernal rule applies when it comes > > > > down to sycnhronized idle time for best power savings. > > > > > > > > The patches below are for #2. There is a known problem with LOW RES > > > > timer mode that I am working on. But I am hoping to get review > > > > earlier. > > > > > > > > > > I also like #2 too. Specially now that it is not limited to a specific > > > platform. One question though, could you still keep the cooling device > > > support of it? In some systems, it might make sense to enable / > > > disable idle injections based on temperature. > > > > > One of the key difference between 1 and 2 is that #2 is open loop > > control, since we don't have CPU c-states info baked into scheduler. To > > close the loop, perhaps we can export some internal APIs to the thermal > > subsystem then the thermal governors can pick the condition to inject > > idle. Jacob, I also like this direction. Having the proper APIs exported, creating a cooling device that use them would be natural path. Then, one could create a thermal zone plugging a governor and the idle injection cooling device that uses the exported APIs. > > > Was there any particular reason you dropped the cooling device > > > support? > > > > > I did sysctl instead of thermal sysfs to conform the rest of the sched > > tuning knobs. We could also have a proxy cooling device to call > > internal APIs mentioned above. Agreed here then. > I think we should have cooling device as we are already using this > cooling device. Once it pass RFC stage,I think we should consider add > this. Srinivas, Yes, that seens to be a good path to follow. Thanks. > Thanks, > Srinivas > > > > Another reason is that, I intend to extend beyond thermal. Where we can > > consolidate/sync idle work in semi-active and balanced workload. I see. BR, Eduardo Valentin -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
