powerpc/smp: Disable MC domain for shared processor

Like L2-cache info, coregroup information which is used to determine MC
sched domains is only present on dedicated LPARs. i.e PowerVM doesn't
export coregroup information for shared processor LPARs. Hence disable
creating MC domains on shared LPAR Systems.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231214180720.310852-3-srikar@linux.vnet.ibm.com

diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 3fc8ad9646a442676cb751fd34e300339f574bc3..2cebc53e97f950ab57d3b9af337f2ea0ded9decf 100644 (file)
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -1055,6 +1055,10 @@ static struct cpumask *cpu_coregroup_mask(int cpu)
 
 static bool has_coregroup_support(void)
 {
+       /* Coregroup identification not available on shared systems */
+       if (is_shared_processor())
+               return 0;
+
        return coregroup_enabled;
 }