From: Mark Brown broonie@linaro.org
As a legacy of the way 32 bit ARM did things the topology code uses a null topology map by default and then overwrites it by mapping cores with no information to a cluster by themselves later. In order to make it simpler to reset things as part of recovering from parse failures in firmware information directly set this configuration on init. A core will always be its own sibling so there should be no risk of confusion with firmware provided information.
Signed-off-by: Mark Brown broonie@linaro.org --- arch/arm64/kernel/topology.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index 3e06b0be4ec8..ff662b23af5f 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -43,9 +43,6 @@ static void update_siblings_masks(unsigned int cpuid) * reset it to default behaviour */ pr_debug("CPU%u: No topology information configured\n", cpuid); - cpuid_topo->core_id = 0; - cpumask_set_cpu(cpuid, &cpuid_topo->core_sibling); - cpumask_set_cpu(cpuid, &cpuid_topo->thread_sibling); return; }
@@ -87,9 +84,12 @@ void __init init_cpu_topology(void) struct cpu_topology *cpu_topo = &cpu_topology[cpu];
cpu_topo->thread_id = -1; - cpu_topo->core_id = -1; + cpu_topo->core_id = 0; cpu_topo->cluster_id = -1; + cpumask_clear(&cpu_topo->core_sibling); + cpumask_set_cpu(cpu, &cpu_topo->core_sibling); cpumask_clear(&cpu_topo->thread_sibling); + cpumask_set_cpu(cpu, &cpu_topo->thread_sibling); } }