Re: [PATCH] sched/clock: Remove pointless test in cpu_clock/local_clock

[Daniel Lezcano]

On 04/01/2016 05:10 PM, Peter Zijlstra wrote:
> On Fri, Apr 01, 2016 at 03:46:48PM +0200, Daniel Lezcano wrote:
>
> > Remove the duplicate test by directly calling sched_clock_cpu() and let the
> > static key act in this function instead. We can assume gcc is smart enough to
> > inline cpu_clock()/local_clock() to sched_clock_cpu().
>
> Why assume if you can easily check; so does it indeed inline?

Actually, no. They are not inlined.

With this patch we end up with one line functions:

#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK

u64 cpu_clock(int cpu)
{
	return sched_clock_cpu(cpu);
}

u64 local_clock(void)
{
	return sched_clock_cpu(raw_smp_processor_id());
}

#else

u64 cpu_clock(int cpu)
{
	return sched_clock();
}

u64 local_clock(void)
{
	return sched_clock();
}

#endif

is it worth to convert them to static inline function ?

(static inline does effectively inline those functions).

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