Re: [PATCH v2 2/3] PM / DEVFREQ: add example governors

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Wednesday, May 18, 2011, MyungJoo Ham wrote:
> 2011/5/18 Rafael J. Wysocki <rjw@xxxxxxx>:
> > On Wednesday, May 11, 2011, MyungJoo Ham wrote:
> >> Three CPUFREQ-like governors are provided as examples.
> >>
> >> powersave: use the lowest frequency possible. The user (device) should
> >> set the polling_ms as 0 because polling is useless for this governor.
> >>
> >> performance: use the highest freqeuncy possible. The user (device)
> >> should set the polling_ms as 0 because polling is useless for this
> >> governor.
> >>
> >> simple_ondemand: simplified version of CPUFREQ's ONDEMAND governor.
> >>
> >> When a user updates OPP entries (enable/disable/add), OPP framework
> >> automatically notifies DEVFREQ to update operating frequency
> >> accordingly. Thus, DEVFREQ users (device drivers) do not need to update
> >> DEVFREQ manually with OPP entry updates or set polling_ms for powersave
> >> , performance, or any other "static" governors.
> >
> > Well, do you expect anyone to actually use them?  If not, it would make
> > more sense to put them into a doc.
> 
> According to our experiences of DVFS(although this "DEVFREQ" is not
> applied to them, yet) in memory-bus and GPU,
> I expect most DEVFREQ users might use "simple_ondemand" and
> expect "powersave" and "performance" will probably mostly used while
> testing and debugging.
> ("userspace"-like governor would be also useful for that purpose, but
> I'd add it later)

It would be good to have at least one in-tree user for each of them
(not necessarily from the start, but at one point in the future at least).

So if you have any _specific_ users in mind, please let me know.

Thanks,
Rafael
_______________________________________________
linux-pm mailing list
linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx
https://lists.linux-foundation.org/mailman/listinfo/linux-pm


[Index of Archives]     [Linux ACPI]     [Netdev]     [Ethernet Bridging]     [Linux Wireless]     [CPU Freq]     [Kernel Newbies]     [Fedora Kernel]     [Security]     [Linux for Hams]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux RAID]     [Linux Admin]     [Samba]

  Powered by Linux