x86, amd: Use compute unit information to determine thread siblings

This information is vital for different load balancing policies.

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
LKML-Reference: <20100930124156.GF20545@loge.amd.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

1 files changed, 20 insertions, 8 deletions

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 8b3bfc4dd708..bc2cc444844a 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -397,6 +397,19 @@ void __cpuinit smp_store_cpu_info(int id)
                 identify_secondary_cpu(c);
 }
 
+static void __cpuinit link_thread_siblings(int cpu1, int cpu2)
+{
+        struct cpuinfo_x86 *c1 = &cpu_data(cpu1);
+        struct cpuinfo_x86 *c2 = &cpu_data(cpu2);
+
+        cpumask_set_cpu(cpu1, cpu_sibling_mask(cpu2));
+        cpumask_set_cpu(cpu2, cpu_sibling_mask(cpu1));
+        cpumask_set_cpu(cpu1, cpu_core_mask(cpu2));
+        cpumask_set_cpu(cpu2, cpu_core_mask(cpu1));
+        cpumask_set_cpu(cpu1, c2->llc_shared_map);
+        cpumask_set_cpu(cpu2, c1->llc_shared_map);
+}
+
 
 void __cpuinit set_cpu_sibling_map(int cpu)
 {
@@ -409,14 +422,13 @@ void __cpuinit set_cpu_sibling_map(int cpu)
                 for_each_cpu(i, cpu_sibling_setup_mask) {
                         struct cpuinfo_x86 *o = &cpu_data(i);
 
-                        if (c->phys_proc_id == o->phys_proc_id &&
-                            c->cpu_core_id == o->cpu_core_id) {
-                                cpumask_set_cpu(i, cpu_sibling_mask(cpu));
-                                cpumask_set_cpu(cpu, cpu_sibling_mask(i));
-                                cpumask_set_cpu(i, cpu_core_mask(cpu));
-                                cpumask_set_cpu(cpu, cpu_core_mask(i));
-                                cpumask_set_cpu(i, c->llc_shared_map);
-                                cpumask_set_cpu(cpu, o->llc_shared_map);
+                        if (cpu_has(c, X86_FEATURE_TOPOEXT)) {
+                                if (c->phys_proc_id == o->phys_proc_id &&
+                                    c->compute_unit_id == o->compute_unit_id)
+                                        link_thread_siblings(cpu, i);
+                        } else if (c->phys_proc_id == o->phys_proc_id &&
+                                   c->cpu_core_id == o->cpu_core_id) {
+                                link_thread_siblings(cpu, i);
                         }
                 }
         } else {