From f2e7c2fc8945943699f745c405be82ac7e698275 Mon Sep 17 00:00:00 2001
From: Yang Weijiang <weijiang.yang@intel.com>
Date: Tue, 15 Feb 2022 14:52:57 -0500
Subject: [PATCH] target/i386: Enable Arch LBR migration states in vmstate

The Arch LBR record MSRs and control MSRs will be migrated
to destination guest if the vcpus were running with Arch
LBR active.

Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
Message-Id: <20220215195258.29149-8-weijiang.yang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 target/i386/machine.c | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/target/i386/machine.c b/target/i386/machine.c
index 7c54bada81..cecd476e98 100644
--- a/target/i386/machine.c
+++ b/target/i386/machine.c
@@ -136,6 +136,22 @@ static const VMStateDescription vmstate_mtrr_var = {
 #define VMSTATE_MTRR_VARS(_field, _state, _n, _v)                    \
     VMSTATE_STRUCT_ARRAY(_field, _state, _n, _v, vmstate_mtrr_var, MTRRVar)
 
+static const VMStateDescription vmstate_lbr_records_var = {
+    .name = "lbr_records_var",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT64(from, LBREntry),
+        VMSTATE_UINT64(to, LBREntry),
+        VMSTATE_UINT64(info, LBREntry),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+#define VMSTATE_LBR_VARS(_field, _state, _n, _v)                    \
+    VMSTATE_STRUCT_ARRAY(_field, _state, _n, _v, vmstate_lbr_records_var, \
+                         LBREntry)
+
 typedef struct x86_FPReg_tmp {
     FPReg *parent;
     uint64_t tmp_mant;
@@ -1525,6 +1541,27 @@ static const VMStateDescription vmstate_amx_xtile = {
 };
 #endif
 
+static bool arch_lbr_needed(void *opaque)
+{
+    X86CPU *cpu = opaque;
+    CPUX86State *env = &cpu->env;
+
+    return !!(env->features[FEAT_7_0_EDX] & CPUID_7_0_EDX_ARCH_LBR);
+}
+
+static const VMStateDescription vmstate_arch_lbr = {
+    .name = "cpu/arch_lbr",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .needed = arch_lbr_needed,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT64(env.msr_lbr_ctl, X86CPU),
+        VMSTATE_UINT64(env.msr_lbr_depth, X86CPU),
+        VMSTATE_LBR_VARS(env.lbr_records, X86CPU, ARCH_LBR_NR_ENTRIES, 1),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
 const VMStateDescription vmstate_x86_cpu = {
     .name = "cpu",
     .version_id = 12,
@@ -1668,6 +1705,7 @@ const VMStateDescription vmstate_x86_cpu = {
 #ifdef TARGET_X86_64
         &vmstate_amx_xtile,
 #endif
+        &vmstate_arch_lbr,
         NULL
     }
 };