On Thu, Aug 19, 2010 at 04:51:20PM -0400, Fenghua Yu wrote: > On Thu, Aug 19, 2010 at 09:27:19AM -0700, Guenter Roeck wrote: > > On Thu, Aug 19, 2010 at 11:46:32AM -0400, Jean Delvare wrote: > > > Hi Fenghua, Guenter, > > > > > > Sorry for joining the discussion a little late, I was on vacation when > > > it happened. I'll comment now, it's probably "too late" as the patch > > > set was merged meanwhile, but still... > > > > > There was no discussion at all, unfortunately. > > > > > On Thu, 22 Jul 2010 14:21:11 -0700, Fenghua Yu wrote: > > > > On Thu, Jul 22, 2010 at 11:58:14AM -0700, Guenter Roeck wrote: > > > > > You use the argument that there may be other package level sensors in the future. > > > > > Are there any plans for this, or is this just a theory ? > > > > > > > > Not just a theory. Sandy Bridge already implements other package level sensors. > > > > If really need to know exactly which sensors are implemented, we might go > > > > through a channel before releasing the info. > > > > > > > > > Next question is how to handle future sensor types. One hwmon instance per sensor, > > > > > additional sensors in this driver, or even a new driver ? > > > > > > > > Currently package level thermal just reports the maximum temperature across > > > > the package. Which sensor is reporting the highest temperature is not exposed. > > > > > > So this isn't a real physical sensor, but more of a meta-sensor? If > > > this is a case, then we don't need support for this at all. User-space > > > can compute a maximum by itself, we don't need a dedicated kernel > > > driver for that. > > > > The pkgtemp reports thermal status for a set of sensors in a package. Please > note the sensors in a package are not limited to processor sensors which are > handled by coretemp. The sensors in a package also include gfx sensors, cache > sensors, memory controllor sensors which are not handled by any hwmon drivers. > > OS gets maximum package thermal status only from MSR PACKAGE_THERM_STATUS. > There is no detailed thermal info for each sensor in a package. User-space > can't compute a maximum by itself. So a piece of kernel driver code, whether > a seperate driver or a integrated driver, is necessary if user-space wants to > know thermal status of a package. > > > > > > We had was a separate discussion if the coretemp driver should be redesigned > > > > > to one instance per CPU. The package sensor would fit into that model, > > > > > since you would have > > > > > > > > > > coretemp-isa-0000 > > > > > Core0 > > > > > Core1 > > > > > ... > > > > > CoreN > > > > > Package > > > > > > > > > > coretemp-isa-0001 > > > > > Core0 > > > > > Core1 > > > > > ... > > > > > CoreM > > > > > Package > > > > > > > > > > I personally would prefer that approach. It would avoid ambiguity associating Package X > > > > > with specific cores, and it would also easily expand to additional non-core future sensors. > > > > > > For the records, I totally support this approach. I want the coretemp > > > driver to be updated to present a single hwmon device per CPU, no > > > matter what happens to the "package temperature". > > > > > I might spend some time rewriting the coretemp driver as described above, > > unless someone else picks it up, and unless there is opposition. > > Obviously, that won't include the package sensor since there is now > > a separate driver for it. > I agree with this method too. On a multiple socket system, the current coretemp > output will cause confusion since it only outputs core# without package#. > > If it's ok for you, I can rewrite this part to have hwmon device per CPU with > both core and package thermal info and send out RFC patch soon. > Sounds good to me. Guenter _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
