On Tuesday, February 28, 2012, Antti P Miettinen wrote: > Adding people that were part of the thread in the beginning.. > > mark gross <markgross@xxxxxxxxxxx> writes: > > On Mon, Feb 27, 2012 at 04:04:00PM +0100, Antti Miettinen wrote: > >> To the lists too.. > >> > >> On 02/27/2012 04:49 PM, Kevin Hilman wrote: > >> > mark gross <markgross@xxxxxxxxxxx> writes: > >> > > >> > >> Current QoS settings could be thought of as performance constraints > >> > >> too. It's just that they determine minimum performance. Adding > >> > >> constraints for maxium performance is not a big stretch in my mind. > >> > > > >> > > Its not a big stretch to me either. I just think its a bit of a hack > >> > > and there is a bigger more interesting issue getting overlooked. > >> > > > >> > > Lastly why not simply make cpufreq thermal aware and talk directly to > >> > > it if you even need too? > >> > > >> > In fact, making a thermal framework "cooling device" that talks directly > >> > to CPUfreq is already what's being done by the Linaro PMWG folks. > >> > > >> > The problem is that CPUfreq only controls the CPU frequency. > >> > > >> > There are other devices that could be scaled back to reduce heat as well > >> > (DSP, and especially GPU), so having a more generic per-device > >> > constraint interface that can cap the frequency for *any* scalable > >> > device is a better framework IMO. > >> > > >> > It just so happens that pm_qos is already a good per-device constraint > >> > framework and can easily modified to cap performance as well as request > >> > a minimum performance. > >> > > >> > Kevin > > > > ok I'll stop trying to block it. > > > > I want to re-do the whole works anyway. If this helps in the mean time > > then go for it. > > Great :-) > > So what do other people think? Could we merge global CPU frequency > constraints for now? Not without an ACK from Dave (the cpufreq maintainer), that's for sure. > I agree that more work is needed for e.g. per CPU constraints, user > space interface and more complete thermal management. Actually for > future I think the constraints could also become more general than just > min/max "reduction operators". For e.g. core online status you might > want union/intersection of bitmaps. Also, the more complete thermal > management is related to load management in general (power budgeting for > other reasons than just thermal). Then perhaps let's not merge "temporary" stuff and figure out how to implement what we _really_ want. Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
