x86/AMD: distinguish compute units from hyper-threads
authorJan Beulich <jbeulich@suse.com>
Thu, 19 Jul 2018 07:42:42 +0000 (09:42 +0200)
committerJan Beulich <jbeulich@suse.com>
Thu, 19 Jul 2018 07:42:42 +0000 (09:42 +0200)
Fam17 replaces CUs by HTs, which we should reflect accordingly, even if
the difference is not very big. The most relevant change (requiring some
code restructuring) is that the topoext feature no longer means there is
a valid CU ID.

Take the opportunity and convert wrongly plain int variables in
set_cpu_sibling_map() to unsigned int.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Brian Woods <brian.woods@amd.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
xen/arch/x86/cpu/amd.c
xen/arch/x86/smpboot.c

index bad5b436287e3bba5ef2e75a26d2be142b5b6bed..a7afa2fa7ae10c8910d6920ba841b98635a80241 100644 (file)
@@ -504,17 +504,23 @@ static void amd_get_topology(struct cpuinfo_x86 *c)
                 u32 eax, ebx, ecx, edx;
 
                 cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
-                c->compute_unit_id = ebx & 0xFF;
                 c->x86_num_siblings = ((ebx >> 8) & 0x3) + 1;
+
+                if (c->x86 < 0x17)
+                        c->compute_unit_id = ebx & 0xFF;
+                else {
+                        c->cpu_core_id = ebx & 0xFF;
+                        c->x86_max_cores /= c->x86_num_siblings;
+                }
         }
         
         if (opt_cpu_info)
                 printk("CPU %d(%d) -> Processor %d, %s %d\n",
                        cpu, c->x86_max_cores, c->phys_proc_id,
-                       cpu_has(c, X86_FEATURE_TOPOEXT) ? "Compute Unit" : 
-                                                         "Core",
-                       cpu_has(c, X86_FEATURE_TOPOEXT) ? c->compute_unit_id :
-                                                         c->cpu_core_id);
+                       c->compute_unit_id != INVALID_CUID ? "Compute Unit"
+                                                          : "Core",
+                       c->compute_unit_id != INVALID_CUID ? c->compute_unit_id
+                                                          : c->cpu_core_id);
 }
 
 static void early_init_amd(struct cpuinfo_x86 *c)
index d4478e61328274fff02897356502f9f64f1e824f..78ba73578a00d3b5a6d407824d6540d638c7e728 100644 (file)
@@ -234,33 +234,41 @@ static void link_thread_siblings(int cpu1, int cpu2)
     cpumask_set_cpu(cpu2, per_cpu(cpu_core_mask, cpu1));
 }
 
-static void set_cpu_sibling_map(int cpu)
+static void set_cpu_sibling_map(unsigned int cpu)
 {
-    int i;
+    unsigned int i;
     struct cpuinfo_x86 *c = cpu_data;
 
     cpumask_set_cpu(cpu, &cpu_sibling_setup_map);
 
     cpumask_set_cpu(cpu, socket_cpumask[cpu_to_socket(cpu)]);
+    cpumask_set_cpu(cpu, per_cpu(cpu_core_mask, cpu));
+    cpumask_set_cpu(cpu, per_cpu(cpu_sibling_mask, cpu));
 
     if ( c[cpu].x86_num_siblings > 1 )
     {
         for_each_cpu ( i, &cpu_sibling_setup_map )
         {
-            if ( cpu_has(c, X86_FEATURE_TOPOEXT) ) {
-                if ( (c[cpu].phys_proc_id == c[i].phys_proc_id) &&
-                     (c[cpu].compute_unit_id == c[i].compute_unit_id) )
+            if ( cpu == i || c[cpu].phys_proc_id != c[i].phys_proc_id )
+                continue;
+            if ( c[cpu].compute_unit_id != INVALID_CUID &&
+                 c[i].compute_unit_id != INVALID_CUID )
+            {
+                if ( c[cpu].compute_unit_id == c[i].compute_unit_id )
+                    link_thread_siblings(cpu, i);
+            }
+            else if ( c[cpu].cpu_core_id != XEN_INVALID_CORE_ID &&
+                      c[i].cpu_core_id != XEN_INVALID_CORE_ID )
+            {
+                if ( c[cpu].cpu_core_id == c[i].cpu_core_id )
                     link_thread_siblings(cpu, i);
-            } else if ( (c[cpu].phys_proc_id == c[i].phys_proc_id) &&
-                        (c[cpu].cpu_core_id == c[i].cpu_core_id) ) {
-                link_thread_siblings(cpu, i);
             }
+            else
+                printk(XENLOG_WARNING
+                       "CPU%u: unclear relationship with CPU%u\n",
+                       cpu, i);
         }
     }
-    else
-    {
-        cpumask_set_cpu(cpu, per_cpu(cpu_sibling_mask, cpu));
-    }
 
     if ( c[cpu].x86_max_cores == 1 )
     {