Re: [PATCH 2/4] sched/core: Export symbols used by cpuidle governors

[Peter Zijlstra]

On Thu, Nov 25, 2021 at 07:01:44PM +0530, Maulik Shah wrote:
> Hi Peter,
> 
> On 11/25/2021 3:05 PM, Peter Zijlstra wrote:
> > On Thu, Nov 25, 2021 at 02:24:39PM +0530, Maulik Shah wrote:
> > > Export symbols that are used by cpuidle menu governor in preparation
> > > to allow cpuidle governors to be compiled as modules.
> > > 
> > > Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> > > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> > > Cc: Juri Lelli <juri.lelli@xxxxxxxxxx>
> > > Cc: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
> > > Signed-off-by: Maulik Shah <quic_mkshah@xxxxxxxxxxx>
> > > ---
> > >   kernel/sched/core.c | 1 +
> > >   1 file changed, 1 insertion(+)
> > > 
> > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> > > index 8cffe31..1d031e0 100644
> > > --- a/kernel/sched/core.c
> > > +++ b/kernel/sched/core.c
> > > @@ -5047,6 +5047,7 @@ unsigned int nr_iowait_cpu(int cpu)
> > >   {
> > >   	return atomic_read(&cpu_rq(cpu)->nr_iowait);
> > >   }
> > > +EXPORT_SYMBOL(nr_iowait_cpu);
> > NACK, that function is batshit insane, exporting it serves nobody.
> Thanks for the review.
> Exporting is to serve cpuidle menu governor when its compiled as module
> (last patch in this series).
> 
> otherwise we get below error during compilation,
> ERROR: modpost: "nr_iowait_cpu" [drivers/cpuidle/governors/menu.ko]
> undefined!
> 
> Do you suggest to use something else instead of this?

Yeah, schedutil :-)