Re: [PATCH 6/7] cputime: Introduce vtime accounting check for readers

Frederic Weisbecker
2015-11-23T14:19:25Z

On Thu, Nov 19, 2015 at 09:28:28PM +0100, Peter Zijlstra wrote:
> On Thu, Nov 19, 2015 at 04:47:33PM +0100, Frederic Weisbecker wrote:
> > +++ b/include/linux/vtime.h
> > @@ -17,9 +17,20 @@ static inline bool vtime_accounting_cpu_enabled(void) { return true; }
> > #endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
> >
> > #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
> > +/*
> > + * Checks if vtime is enabled on some CPU. Cputime readers want to be careful
> > + * in that case and compute the tickless cputime.
> > + * For now vtime state is tied to context tracking. We might want to decouple
> > + * those later if necessary.
> > + */
> > +static inline bool vtime_accounting_enabled(void)
> > +{
> > + return context_tracking_is_enabled();
> > +}
>
> Should this not also include a definition of this function for
> CONFIG_VIRT_CPU_ACCOUNTING_NATIVE and CONFIG_VIRT_CPU_ACCOUNTING ?

I could but I haven't found any user of it yet for others than
CONFIG_VIRT_CPU_ACCOUNTING_GEN. The NATIVE version, when enabled, runs on
all CPUs anyway.