Re: [PATCH] arm64: topology: Drop the useless update to per-cpu cycles

From: Catalin Marinas
Date: Tue Dec 15 2020 - 07:31:56 EST


On Fri, Dec 11, 2020 at 12:18:50PM +0530, Viresh Kumar wrote:
> On 10-12-20, 11:17, Viresh Kumar wrote:
> > The previous call to update_freq_counters_refs() has already updated the
> > per-cpu variables, don't overwrite them with the same value again.
> >
> > Fixes: 4b9cf23c179a ("arm64: wrap and generalise counter read functions")
> > Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> > ---
> > arch/arm64/kernel/topology.c | 6 +-----
> > 1 file changed, 1 insertion(+), 5 deletions(-)
> >
> > diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c
> > index c8308befdb1e..f6faa697e83e 100644
> > --- a/arch/arm64/kernel/topology.c
> > +++ b/arch/arm64/kernel/topology.c
> > @@ -314,7 +314,7 @@ void topology_scale_freq_tick(void)
> >
> > if (unlikely(core_cnt <= prev_core_cnt ||
> > const_cnt <= prev_const_cnt))
> > - goto store_and_exit;
> > + return;
> >
> > /*
> > * /\core arch_max_freq_scale
> > @@ -331,10 +331,6 @@ void topology_scale_freq_tick(void)
> >
> > scale = min_t(unsigned long, scale, SCHED_CAPACITY_SCALE);
> > this_cpu_write(freq_scale, (unsigned long)scale);
> > -
> > -store_and_exit:
> > - this_cpu_write(arch_core_cycles_prev, core_cnt);
> > - this_cpu_write(arch_const_cycles_prev, const_cnt);
> > }
> >
> > #ifdef CONFIG_ACPI_CPPC_LIB
>
> Catalin: Can you please pick this up for 5.11-rc1, the earlier patch
> (from fixes) is already in your tree. Thanks.

I will add it to the second pull request this merging window. Thanks.

--
Catalin