Re: [PATCH] RFC: nomadik: expand timesource to 63 bits

Linus Walleij
2010-11-12T10:38:45Z

Thomas Gleixner wrote:
> On Fri, 12 Nov 2010, Linus Walleij wrote:
>> Uwe Kleine-König wrote:
>>
>>> Instead of implementing sched_clock for each architecture seperatly,
>>> wouldn't it be nice to have a generic sched_clock that uses the
>>> architecture's clocksource? I tried to implement that some time ago,
>>> but tglx shoot it down because of locking problems.
>> I was and still am a big fan of this approach, I am willing to help
>> testing it if you want to dust off this patch set...
>
> sched_clock is not necessarily the same as the current clocksource.

IIRC Uwe:s approach was that if and only if you would want to use
the clocksource for sched_clock() you provide a special flag on
the clocksource, and it will be attempted to be used for sched_clock().

Incidentally the dual use of a single free-running timer as both
single clocksource and sched_clock() baseline seem to creep up in
a lot of embedded platforms...

Yours,
Linus Walleij