Messages in this thread | | | Date | Wed, 28 Apr 2004 21:19:08 +0200 | From | Dominik Brodowski <> | Subject | Re: [CHECKER] Implementation inconsistencies involving writes |
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On Tue, Apr 27, 2004 at 08:54:15PM -0700, Ken Ashcraft wrote: > I'm trying to cross check implementations of the same interface for > errors. I assume that if functions are assigned to the same function > pointer, they are implementations of a common interface and should be > consistent with each other.
> [BUG] <linux@brodo.de> not writing policy->governor. looks like it is > necessary to write a default value there.
It surely _looks like_ it's a bug, but it isn't. cpufreq drivers can either have a "->target" or a "->setpolicy" function defined in the cpufreq_driver struct. If it's ->target, ->governor needs to be set, if it's ->setpolicy, ->governor may not be set, or at least should not be set. As there's only one ->setpolicy cpufreq driver (longrun), it's not as clear as it should be.
The difference between target and setpolicy cpufreq drivers is the following: on the first type, the CPU can be set to run at a specific frequency. setpolicy drivers can set the CPU to a frequency range; the CPU itself at which frequency to run within this range -- an interesting feature of Transmeta CPUs, which made this distinction necessary.
Dominik [unhandled content-type:application/pgp-signature] | |