Li, Aubrey wrote: > Mark Haywood wrote: > > >> Eric Saxe wrote: >> >>> Mark Haywood wrote: >>> >>> >>>> Beautiful. Thanks for doing that. Anup and I just took a quick look >>>> at the webrev and had a question about cpupm_num_groups() in >>>> cpu_pm.c. We didn't understand the comment at the top of the >>>> routine and weren't sure how to provide you with the "guts" for the >>>> routine. >>>> >>>> >>> I was initially trying to provide for the possibility that there are >>> multiple levels of CPU power management for a given CPU. For >>> example, if we're able to quiesce an entire core, perhaps we'll drop >>> the frequency...but if we can quiesce the socket, we (or at least >>> the CPU) can also drop the voltage. This interface returns the >>> number of "levels"...since the PG framework could create multiple >>> levels of groupings to implement scheduling policy against... >>> >>> But I actually think I can get away with just having the second >>> interface alone...please see below.. >>> >>> Does ACPI define distinct domains for logical CPUs which can share a >>> frequency change, and logical CPUs which can share a voltage change? >>> >>> >> I assume that you are referring to P-state domains. If so, no the >> P-state domains combine both frequency and voltage in the domain. >> > > I guess Eric means P-state and C-state. > If so, _PSD describes P-State Dependency and _CSD describes C-state > Dependency. >
Ah. Sorry. I'm familiar with the _CSD (and of course the _PSD), but didn't recognize what Eric was referring to. So, I assume that means _PSD defines the CPUs that share frequency change and C-state dependency defines the CPUs that share a voltage change? I'm not sure that's how I'd think of it, but OK. > Thanks, > -Aubrey > _______________________________________________ > tesla-dev mailing list > tesla-dev at opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/tesla-dev >
