diff mbox series

[v6,08/16] i386: Expose module level in CPUID[0x1F]

Message ID 20231117075106.432499-9-zhao1.liu@linux.intel.com (mailing list archive)
State New, archived
Headers show
Series Support smp.clusters for x86 in QEMU | expand

Commit Message

Zhao Liu Nov. 17, 2023, 7:50 a.m. UTC 
From: Zhao Liu <zhao1.liu@intel.com>

Linux kernel (from v6.4, with commit edc0a2b595765 ("x86/topology: Fix
erroneous smp_num_siblings on Intel Hybrid platforms") is able to
handle platforms with Module level enumerated via CPUID.1F.

Expose the module level in CPUID[0x1F] if the machine has more than 1
modules.

(Tested CPU topology in CPUID[0x1F] leaf with various die/cluster
configurations in "-smp".)

Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Tested-by: Yongwei Ma <yongwei.ma@intel.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
---
Changes since v3:
 * New patch to expose module level in 0x1F.
 * Add Tested-by tag from Yongwei.
---
 target/i386/cpu.c     | 12 +++++++++++-
 target/i386/cpu.h     |  2 ++
 target/i386/kvm/kvm.c |  2 +-
 3 files changed, 14 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index b4055e4dd62e..0fcdd6f5f349 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -277,6 +277,8 @@  static uint32_t num_cpus_by_topo_level(X86CPUTopoInfo *topo_info,
         return 1;
     case CPU_TOPO_LEVEL_CORE:
         return topo_info->threads_per_core;
+    case CPU_TOPO_LEVEL_MODULE:
+        return topo_info->threads_per_core * topo_info->cores_per_module;
     case CPU_TOPO_LEVEL_DIE:
         return topo_info->threads_per_core * topo_info->cores_per_module *
                topo_info->modules_per_die;
@@ -297,6 +299,8 @@  static uint32_t apicid_offset_by_topo_level(X86CPUTopoInfo *topo_info,
         return 0;
     case CPU_TOPO_LEVEL_CORE:
         return apicid_core_offset(topo_info);
+    case CPU_TOPO_LEVEL_MODULE:
+        return apicid_module_offset(topo_info);
     case CPU_TOPO_LEVEL_DIE:
         return apicid_die_offset(topo_info);
     case CPU_TOPO_LEVEL_PACKAGE:
@@ -316,6 +320,8 @@  static uint32_t cpuid1f_topo_type(enum CPUTopoLevel topo_level)
         return CPUID_1F_ECX_TOPO_LEVEL_SMT;
     case CPU_TOPO_LEVEL_CORE:
         return CPUID_1F_ECX_TOPO_LEVEL_CORE;
+    case CPU_TOPO_LEVEL_MODULE:
+        return CPUID_1F_ECX_TOPO_LEVEL_MODULE;
     case CPU_TOPO_LEVEL_DIE:
         return CPUID_1F_ECX_TOPO_LEVEL_DIE;
     default:
@@ -347,6 +353,10 @@  static void encode_topo_cpuid1f(CPUX86State *env, uint32_t count,
         if (env->nr_dies > 1) {
             set_bit(CPU_TOPO_LEVEL_DIE, topo_bitmap);
         }
+
+        if (env->nr_modules > 1) {
+            set_bit(CPU_TOPO_LEVEL_MODULE, topo_bitmap);
+        }
     }
 
     *ecx = count & 0xff;
@@ -6393,7 +6403,7 @@  void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
         break;
     case 0x1F:
         /* V2 Extended Topology Enumeration Leaf */
-        if (topo_info.dies_per_pkg < 2) {
+        if (topo_info.modules_per_die < 2 && topo_info.dies_per_pkg < 2) {
             *eax = *ebx = *ecx = *edx = 0;
             break;
         }
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index da58d41c9969..95cbbb1de906 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -1018,6 +1018,7 @@  enum CPUTopoLevel {
     CPU_TOPO_LEVEL_INVALID,
     CPU_TOPO_LEVEL_SMT,
     CPU_TOPO_LEVEL_CORE,
+    CPU_TOPO_LEVEL_MODULE,
     CPU_TOPO_LEVEL_DIE,
     CPU_TOPO_LEVEL_PACKAGE,
     CPU_TOPO_LEVEL_MAX,
@@ -1032,6 +1033,7 @@  enum CPUTopoLevel {
 #define CPUID_1F_ECX_TOPO_LEVEL_INVALID  CPUID_B_ECX_TOPO_LEVEL_INVALID
 #define CPUID_1F_ECX_TOPO_LEVEL_SMT      CPUID_B_ECX_TOPO_LEVEL_SMT
 #define CPUID_1F_ECX_TOPO_LEVEL_CORE     CPUID_B_ECX_TOPO_LEVEL_CORE
+#define CPUID_1F_ECX_TOPO_LEVEL_MODULE   3
 #define CPUID_1F_ECX_TOPO_LEVEL_DIE      5
 
 /* MSR Feature Bits */
diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index 11b8177eff21..b6d297aff730 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -1913,7 +1913,7 @@  int kvm_arch_init_vcpu(CPUState *cs)
             break;
         }
         case 0x1f:
-            if (env->nr_dies < 2) {
+            if (env->nr_modules < 2 && env->nr_dies < 2) {
                 break;
             }
             /* fallthrough */