[v11,12/21] i386: Introduce module level cpu topology to CPUX86State

Commit Message

Zhao Liu April 24, 2024, 3:49 p.m. UTC

Intel CPUs implement module level on hybrid client products (e.g.,
ADL-N, MTL, etc) and E-core server products.

A module contains a set of cores that share certain resources (in
current products, the resource usually includes L2 cache, as well as
module scoped features and MSRs).

Module level support is the prerequisite for L2 cache topology on
module level. With module level, we can implement the Guest's CPU
topology and future cache topology to be consistent with the Host's on
Intel hybrid client/E-core server platforms.

Tested-by: Yongwei Ma <[e-mail]>
Co-developed-by: Zhuocheng Ding <[e-mail]>
Signed-off-by: Zhuocheng Ding <[e-mail]>
Signed-off-by: Zhao Liu <[e-mail]>
Tested-by: Babu Moger <[e-mail]>
---
Changes since v7:
 * Mapped x86 module to smp module instead of cluster.
 * Re-wrote the commit message to explain the reason why we needs module
   level.
 * Dropped Michael/Babu's ACKed/Tested tags since the code change.
 * Re-added Yongwei's Tested tag For his re-testing.

Changes since v1:
 * The background of the introduction of the "cluster" parameter and its
   exact meaning were revised according to Yanan's explanation. (Yanan)
---
 hw/i386/x86.c     | 5 +++++
 target/i386/cpu.c | 1 +
 target/i386/cpu.h | 3 +++
 3 files changed, 9 insertions(+)

Patch

diff --git a/hw/i386/x86.c b/hw/i386/x86.c
index 004627fa8985..3b5cf75d5bf3 100644
--- a/hw/i386/x86.c
+++ b/hw/i386/x86.c
@@ -313,6 +313,11 @@  void x86_cpu_pre_plug(HotplugHandler *hotplug_dev,
 
     init_topo_info(&topo_info, x86ms);
 
+    if (ms->smp.modules > 1) {
+        env->nr_modules = ms->smp.modules;
+        /* TODO: Expose module level in CPUID[0x1F]. */
+    }
+
     if (ms->smp.dies > 1) {
         env->nr_dies = ms->smp.dies;
         set_bit(CPU_TOPO_LEVEL_DIE, env->avail_cpu_topo);
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 504ec569e0b2..8f34a5b8d726 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -7871,6 +7871,7 @@  static void x86_cpu_init_default_topo(X86CPU *cpu)
 {
     CPUX86State *env = &cpu->env;
 
+    env->nr_modules = 1;
     env->nr_dies = 1;
 
     /* SMT, core and package levels are set by default. */
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index fa9b6679387e..630129838c08 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -1899,6 +1899,9 @@  typedef struct CPUArchState {
     /* Number of dies within this CPU package. */
     unsigned nr_dies;
 
+    /* Number of modules within one die. */
+    unsigned nr_modules;
+
     /* Bitmap of available CPU topology levels for this CPU. */
     DECLARE_BITMAP(avail_cpu_topo, CPU_TOPO_LEVEL_MAX);
 } CPUX86State;