Re: [PATCH] CPU frequency display in /proc/cpuinfo

[Dave Jones]

On Tue, Dec 06, 2005 at 12:13:49PM +0100, Erik Mouw wrote:
 > On Mon, Dec 05, 2005 at 12:25:13PM -0500, Dave Jones wrote:
 > > On Mon, Dec 05, 2005 at 02:02:24PM +0100, Erik Mouw wrote:
 > >  > If you want a userspace governor to change the CPU speed, you need to
 > >  > export the value to userland. 
 > > 
 > > We have sysfs files for that.
 > 
 > Earlier in this thread you said (I should have quoted that, my fault):
 > 
 >   Adding any other interface to obtain this value is equally as broken.
 > 
 > So I'm confused, sysfs one of the "any other interfaces"...

userspace governors need to know the available frequencies to scale to, 
which they obtain from sysfs. In addition, we maintain an index as to
which of those is currently chosen.  However, programs should not rely
on this to be a "how fast is my CPU" status, as it's totally meaningless.
It's there purely for humans to see "Yes, X < Y, so I'm going at the
lower of the frequencies my CPU can do", not for programs to calculate
delays loops and such.

		Dave


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