On Tue, Aug 26, 2025 at 06:49:29AM +0200, Christophe Leroy wrote: > > > Le 26/08/2025 à 06:13, K Prateek Nayak a écrit : > > PowerPC enables the MC scheduling domain by default on systems with > > coregroup support without having a SCHED_MC config in Kconfig. > > > > The scheduler uses CONFIG_SCHED_MC to introduce the MC domain in the > > default topology (core) and to optimize the default CPU selection > > routine (sched-ext). > > > > Introduce CONFIG_SCHED_MC for powerpc and note that it should be > > preferably enabled given the current default behavior. This also ensures > > PowerPC is tested during future developments that come to depend on > > CONFIG_SCHED_MC. > > > > Signed-off-by: K Prateek Nayak <kprateek.na...@amd.com> > > --- > > arch/powerpc/Kconfig | 9 +++++++++ > > arch/powerpc/include/asm/smp.h | 2 ++ > > arch/powerpc/kernel/smp.c | 4 ++++ > > 3 files changed, 15 insertions(+) > > > > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig > > index 93402a1d9c9f..e954ab3f635f 100644 > > --- a/arch/powerpc/Kconfig > > +++ b/arch/powerpc/Kconfig > > @@ -971,6 +971,15 @@ config SCHED_SMT > > when dealing with POWER5 cpus at a cost of slightly increased > > overhead in some places. If unsure say N here. > > +config SCHED_MC > > + bool "Multi-Core Cache (MC) scheduler support" > > + depends on PPC64 && SMP > > + default y > > + help > > + MC scheduler support improves the CPU scheduler's decision making > > + when dealing with POWER systems that contain multiple Last Level > > + Cache instances on the same socket. If unsure say Y here. > > + > > You shouldn't duplicate CONFIG_SCHED_MC in every architecture, instead you > should define a CONFIG_ARCH_HAS_SCHED_MC in arch/Kconfig that gets selected > by architectures then have CONFIG_SCHED_MC defined in init/Kconfig or > kernel/Kconfig or so.
Let me add this first -- it is currently duplicated. Then I'll see about merging the thing across architectures.
