Peter Zijlstra [off-list ref] writes:

On Thu, 2012-10-18 at 08:51 +0300, Felipe Balbi wrote:

quoted

quoted

So the primary question remains: is RT runtime supposed to include the
time spent suspended?  I suspect not. 

you might be right there, though we need Thomas or Peter to answer :-s 

re, sorry both tglx and I have been traveling, he still is, I'm trying
to play catch-up :-)

No worries, thanks for the help.

Anyway, yeah I'm somewhat surprised the clock is 'running' when the
machine isn't. From what I could gather, this is !x86 hardware, right?

x86 explicitly makes sure our clocks are 'stopped' during suspend, see
commit cd7240c0b900eb6d690ccee088a6c9b46dae815a.

Can you do something similar for ARM? A quick look at
arch/arm/kernel/sched_clock.c shows there's already suspend/resume
hooks, do they do the wrong thing?

No, they do the right thing, but only if they're asked by the
SoC-specific code that registers a sched_clock.  Changing the SoC
specific code to use the 'needs_suspend' API gets things working
perfectly.

Thanks,

Kevin