x86/numa: Hard partition cpu topology masks on node boundaries

When using numa=fake= you can get weird topologies where LLCs can span
nodes and other such nonsense. Cure this by hard partitioning these
masks on node boundaries.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/n/tip-di5vwjm96q5vrb76opwuflwx@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 11 insertions, 0 deletions

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 6e1e406038c2..edfd03a9e390 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -337,6 +337,11 @@ void __cpuinit set_cpu_sibling_map(int cpu)
                 for_each_cpu(i, cpu_sibling_setup_mask) {
                         struct cpuinfo_x86 *o = &cpu_data(i);
 
+#ifdef CONFIG_NUMA_EMU
+                        if (cpu_to_node(cpu) != cpu_to_node(i))
+                                continue;
+#endif
+
                         if (cpu_has(c, X86_FEATURE_TOPOEXT)) {
                                 if (c->phys_proc_id == o->phys_proc_id &&
                                     per_cpu(cpu_llc_id, cpu) == per_cpu(cpu_llc_id, i) &&
@@ -360,11 +365,17 @@ void __cpuinit set_cpu_sibling_map(int cpu)
         }
 
         for_each_cpu(i, cpu_sibling_setup_mask) {
+#ifdef CONFIG_NUMA_EMU
+                if (cpu_to_node(cpu) != cpu_to_node(i))
+                        continue;
+#endif
+
                 if (per_cpu(cpu_llc_id, cpu) != BAD_APICID &&
                     per_cpu(cpu_llc_id, cpu) == per_cpu(cpu_llc_id, i)) {
                         cpumask_set_cpu(i, cpu_llc_shared_mask(cpu));
                         cpumask_set_cpu(cpu, cpu_llc_shared_mask(i));
                 }
+
                 if (c->phys_proc_id == cpu_data(i).phys_proc_id) {
                         cpumask_set_cpu(i, cpu_core_mask(cpu));
                         cpumask_set_cpu(cpu, cpu_core_mask(i));