On Tue, 7 May 2019 15:31:27 +0100 Quentin Perret <quentin.per...@arm.com> wrote:
> On Tuesday 07 May 2019 at 16:25:23 (+0200), luca abeni wrote: > > On Tue, 7 May 2019 14:48:52 +0100 > > Quentin Perret <quentin.per...@arm.com> wrote: > > > > > Hi Luca, > > > > > > On Monday 06 May 2019 at 06:48:31 (+0200), Luca Abeni wrote: > > > > diff --git a/drivers/base/arch_topology.c > > > > b/drivers/base/arch_topology.c index edfcf8d982e4..646d6d349d53 > > > > 100644 --- a/drivers/base/arch_topology.c > > > > +++ b/drivers/base/arch_topology.c > > > > @@ -36,6 +36,7 @@ DEFINE_PER_CPU(unsigned long, cpu_scale) = > > > > SCHED_CAPACITY_SCALE; > > > > void topology_set_cpu_scale(unsigned int cpu, unsigned long > > > > capacity) { > > > > + topology_update_cpu_capacity(cpu, per_cpu(cpu_scale, > > > > cpu), capacity); > > > > > > Why is that one needed ? Don't you end up re-building the sched > > > domains after this anyways ? > > > > If I remember correctly, this function was called at boot time when > > the capacities are assigned to the CPU cores. > > > > I do not remember if the sched domain was re-built after this call, > > but I admit I do not know this part of the kernel very well... > > Right and things moved recently in this area, see bb1fbdd3c3fd > ("sched/topology, drivers/base/arch_topology: Rebuild the sched_domain > hierarchy when capacities change") Ah, thanks! I missed this change when rebasing the patchset. I guess this part of the patch has to be updated (and probably became useless?), then. Thanks, Luca > > > This achieved the effect of correctly setting up the "rd_capacity" > > field, but I do not know if there is a better/simpler way to achieve > > the same result :) > > OK, that's really an implementation detail, so no need to worry too > much about it at the RFC stage I suppose :-) > > Thanks, > Quentin