diff mbox series

[RFC,v2,11/19] i386: introduce hv_cpuid_cache

Message ID 20200930134027.1348021-12-vkuznets@redhat.com (mailing list archive)
State New, archived
Headers show
Series i386: KVM: expand Hyper-V features early | expand

Commit Message

Vitaly Kuznetsov Sept. 30, 2020, 1:40 p.m. UTC 
Just like with cpuid_cache, it makes no sense to call
KVM_GET_SUPPORTED_HV_CPUID more than once and instead of (ab)using
env->features[] and/or trying to keep all the code in one place, it is
better to introduce persistent hv_cpuid_cache and hv_cpuid_get_host()
accessor to it.

Note, hv_cpuid_get_fw() is converted to using hv_cpuid_get_host()
just to be removed later with Hyper-V specific feature words.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
 target/i386/kvm.c | 213 +++++++++++++++++++++++-----------------------
 1 file changed, 106 insertions(+), 107 deletions(-)
diff mbox series

Patch

diff --git a/target/i386/kvm.c b/target/i386/kvm.c
index a9823d4af7cb..0e6eef6a52c2 100644
--- a/target/i386/kvm.c
+++ b/target/i386/kvm.c
@@ -124,6 +124,7 @@  static int has_exception_payload;
 static bool has_msr_mcg_ext_ctl;
 
 static struct kvm_cpuid2 *cpuid_cache;
+static struct kvm_cpuid2 *hv_cpuid_cache;
 static struct kvm_msr_list *kvm_feature_msrs;
 
 int kvm_has_pit_state2(void)
@@ -1079,9 +1080,36 @@  static struct kvm_cpuid2 *get_supported_hv_cpuid_legacy(CPUState *cs)
     return cpuid;
 }
 
-static int hv_cpuid_get_fw(struct kvm_cpuid2 *cpuid, int fw, uint32_t *r)
+static uint32_t hv_cpuid_get_host(CPUState *cs, uint32_t func, int reg)
 {
     struct kvm_cpuid_entry2 *entry;
+    struct kvm_cpuid2 *cpuid;
+
+    if (hv_cpuid_cache) {
+        cpuid = hv_cpuid_cache;
+    } else {
+        if (kvm_check_extension(kvm_state, KVM_CAP_HYPERV_CPUID) > 0) {
+            cpuid = get_supported_hv_cpuid(cs);
+        } else {
+            cpuid = get_supported_hv_cpuid_legacy(cs);
+        }
+        hv_cpuid_cache = cpuid;
+    }
+
+    if (!cpuid) {
+        return 0;
+    }
+
+    entry = cpuid_find_entry(cpuid, func, 0);
+    if (!entry) {
+        return 0;
+    }
+
+    return cpuid_entry_get_reg(entry, reg);
+}
+
+static uint32_t hv_cpuid_get_fw(CPUState *cs, int fw)
+{
     uint32_t func;
     int reg;
 
@@ -1099,30 +1127,13 @@  static int hv_cpuid_get_fw(struct kvm_cpuid2 *cpuid, int fw, uint32_t *r)
         func = HV_CPUID_ENLIGHTMENT_INFO;
         break;
     default:
-        return -EINVAL;
-    }
-
-    entry = cpuid_find_entry(cpuid, func, 0);
-    if (!entry) {
-        return -ENOENT;
-    }
-
-    switch (reg) {
-    case R_EAX:
-        *r = entry->eax;
-        break;
-    case R_EDX:
-        *r = entry->edx;
-        break;
-    default:
-        return -EINVAL;
+        return 0;
     }
 
-    return 0;
+    return hv_cpuid_get_host(cs, func, reg);
 }
 
-static int hv_cpuid_check_and_set(CPUState *cs, struct kvm_cpuid2 *cpuid,
-                                  int feature)
+static int hv_cpuid_check_and_set(CPUState *cs, int feature)
 {
     X86CPU *cpu = X86_CPU(cs);
     CPUX86State *env = &cpu->env;
@@ -1155,7 +1166,8 @@  static int hv_cpuid_check_and_set(CPUState *cs, struct kvm_cpuid2 *cpuid,
             continue;
         }
 
-        if (hv_cpuid_get_fw(cpuid, fw, &r) || (r & bits) != bits) {
+        r = hv_cpuid_get_fw(cs, fw);
+        if ((r & bits) != bits) {
             if (hyperv_feat_enabled(cpu, feature)) {
                 fprintf(stderr,
                         "Hyper-V %s is not supported by kernel\n",
@@ -1186,7 +1198,6 @@  static int hyperv_handle_properties(CPUState *cs,
 {
     X86CPU *cpu = X86_CPU(cs);
     CPUX86State *env = &cpu->env;
-    struct kvm_cpuid2 *cpuid;
     struct kvm_cpuid_entry2 *c;
     uint32_t cpuid_i = 0;
     int r;
@@ -1214,92 +1225,85 @@  static int hyperv_handle_properties(CPUState *cs,
         }
     }
 
-    if (kvm_check_extension(cs->kvm_state, KVM_CAP_HYPERV_CPUID) > 0) {
-        cpuid = get_supported_hv_cpuid(cs);
-    } else {
-        cpuid = get_supported_hv_cpuid_legacy(cs);
-    }
-
     if (cpu->hyperv_passthrough) {
-        c = cpuid_find_entry(cpuid, HV_CPUID_VENDOR_AND_MAX_FUNCTIONS, 0);
-        if (c) {
-            cpu->hyperv_vendor_id[0] = c->ebx;
-            cpu->hyperv_vendor_id[1] = c->ecx;
-            cpu->hyperv_vendor_id[2] = c->edx;
-            cpu->hyperv_vendor = g_realloc(cpu->hyperv_vendor,
-                                           sizeof(cpu->hyperv_vendor_id) + 1);
-            memcpy(cpu->hyperv_vendor, cpu->hyperv_vendor_id,
-                   sizeof(cpu->hyperv_vendor_id));
-        }
-
-        c = cpuid_find_entry(cpuid, HV_CPUID_INTERFACE, 0);
-        if (c) {
-            cpu->hyperv_interface_id[0] = c->eax;
-            cpu->hyperv_interface_id[1] = c->ebx;
-            cpu->hyperv_interface_id[2] = c->ecx;
-            cpu->hyperv_interface_id[3] = c->edx;
-        }
-
-        c = cpuid_find_entry(cpuid, HV_CPUID_VERSION, 0);
-        if (c) {
-            cpu->hyperv_version_id[0] = c->eax;
-            cpu->hyperv_version_id[1] = c->ebx;
-            cpu->hyperv_version_id[2] = c->ecx;
-            cpu->hyperv_version_id[3] = c->edx;
-        }
-
-        c = cpuid_find_entry(cpuid, HV_CPUID_FEATURES, 0);
-        if (c) {
-            env->features[FEAT_HYPERV_EAX] = c->eax;
-            env->features[FEAT_HYPERV_EBX] = c->ebx;
-            env->features[FEAT_HYPERV_EDX] = c->edx;
-        }
-
-        c = cpuid_find_entry(cpuid, HV_CPUID_IMPLEMENT_LIMITS, 0);
-        if (c) {
-            cpu->hv_max_vps = c->eax;
-            cpu->hyperv_limits[0] = c->ebx;
-            cpu->hyperv_limits[1] = c->ecx;
-            cpu->hyperv_limits[2] = c->edx;
-        }
-
-        c = cpuid_find_entry(cpuid, HV_CPUID_ENLIGHTMENT_INFO, 0);
-        if (c) {
-            env->features[FEAT_HV_RECOMM_EAX] = c->eax;
-            cpu->hyperv_spinlock_attempts = c->ebx;
-        }
-        c = cpuid_find_entry(cpuid, HV_CPUID_NESTED_FEATURES, 0);
-        if (c) {
-            env->features[FEAT_HV_NESTED_EAX] = c->eax;
-        }
+        cpu->hyperv_vendor_id[0] =
+            hv_cpuid_get_host(cs, HV_CPUID_VENDOR_AND_MAX_FUNCTIONS, R_EBX);
+        cpu->hyperv_vendor_id[1] =
+            hv_cpuid_get_host(cs, HV_CPUID_VENDOR_AND_MAX_FUNCTIONS, R_ECX);
+        cpu->hyperv_vendor_id[2] =
+            hv_cpuid_get_host(cs, HV_CPUID_VENDOR_AND_MAX_FUNCTIONS, R_EDX);
+        cpu->hyperv_vendor = g_realloc(cpu->hyperv_vendor,
+                                       sizeof(cpu->hyperv_vendor_id) + 1);
+        memcpy(cpu->hyperv_vendor, cpu->hyperv_vendor_id,
+               sizeof(cpu->hyperv_vendor_id));
+
+        cpu->hyperv_interface_id[0] =
+            hv_cpuid_get_host(cs, HV_CPUID_INTERFACE, R_EAX);
+        cpu->hyperv_interface_id[1] =
+            hv_cpuid_get_host(cs, HV_CPUID_INTERFACE, R_EBX);
+        cpu->hyperv_interface_id[2] =
+            hv_cpuid_get_host(cs, HV_CPUID_INTERFACE, R_ECX);
+        cpu->hyperv_interface_id[3] =
+            hv_cpuid_get_host(cs, HV_CPUID_INTERFACE, R_EDX);
+
+        cpu->hyperv_version_id[0] =
+            hv_cpuid_get_host(cs, HV_CPUID_VERSION, R_EAX);
+        cpu->hyperv_version_id[1] =
+            hv_cpuid_get_host(cs, HV_CPUID_VERSION, R_EBX);
+        cpu->hyperv_version_id[2] =
+            hv_cpuid_get_host(cs, HV_CPUID_VERSION, R_ECX);
+        cpu->hyperv_version_id[3] =
+            hv_cpuid_get_host(cs, HV_CPUID_VERSION, R_EDX);
+
+        env->features[FEAT_HYPERV_EAX] =
+            hv_cpuid_get_host(cs, HV_CPUID_FEATURES, R_EAX);
+        env->features[FEAT_HYPERV_EBX] =
+            hv_cpuid_get_host(cs, HV_CPUID_FEATURES, R_EBX);
+        env->features[FEAT_HYPERV_EDX] =
+            hv_cpuid_get_host(cs, HV_CPUID_FEATURES, R_EDX);
+
+        cpu->hv_max_vps = hv_cpuid_get_host(cs, HV_CPUID_IMPLEMENT_LIMITS,
+                                            R_EAX);
+        cpu->hyperv_limits[0] =
+            hv_cpuid_get_host(cs, HV_CPUID_IMPLEMENT_LIMITS, R_EBX);
+        cpu->hyperv_limits[1] =
+            hv_cpuid_get_host(cs, HV_CPUID_IMPLEMENT_LIMITS, R_ECX);
+        cpu->hyperv_limits[2] =
+            hv_cpuid_get_host(cs, HV_CPUID_IMPLEMENT_LIMITS, R_EDX);
+
+        env->features[FEAT_HV_RECOMM_EAX] =
+            hv_cpuid_get_host(cs, HV_CPUID_ENLIGHTMENT_INFO, R_EAX);
+        cpu->hyperv_spinlock_attempts =
+            hv_cpuid_get_host(cs, HV_CPUID_ENLIGHTMENT_INFO, R_EBX);
+
+        env->features[FEAT_HV_NESTED_EAX] =
+            hv_cpuid_get_host(cs, HV_CPUID_NESTED_FEATURES, R_EAX);
     }
 
     if (cpu->hyperv_no_nonarch_cs == ON_OFF_AUTO_ON) {
         env->features[FEAT_HV_RECOMM_EAX] |= HV_NO_NONARCH_CORESHARING;
     } else if (cpu->hyperv_no_nonarch_cs == ON_OFF_AUTO_AUTO) {
-        c = cpuid_find_entry(cpuid, HV_CPUID_ENLIGHTMENT_INFO, 0);
-        if (c) {
-            env->features[FEAT_HV_RECOMM_EAX] |=
-                c->eax & HV_NO_NONARCH_CORESHARING;
-        }
+        env->features[FEAT_HV_RECOMM_EAX] |=
+            hv_cpuid_get_host(cs, HV_CPUID_ENLIGHTMENT_INFO, R_EAX) &
+            HV_NO_NONARCH_CORESHARING;
     }
 
     /* Features */
-    r = hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_RELAXED);
-    r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_VAPIC);
-    r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_TIME);
-    r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_CRASH);
-    r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_RESET);
-    r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_VPINDEX);
-    r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_RUNTIME);
-    r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_SYNIC);
-    r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_STIMER);
-    r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_FREQUENCIES);
-    r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_REENLIGHTENMENT);
-    r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_TLBFLUSH);
-    r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_EVMCS);
-    r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_IPI);
-    r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_STIMER_DIRECT);
+    r = hv_cpuid_check_and_set(cs, HYPERV_FEAT_RELAXED);
+    r |= hv_cpuid_check_and_set(cs, HYPERV_FEAT_VAPIC);
+    r |= hv_cpuid_check_and_set(cs, HYPERV_FEAT_TIME);
+    r |= hv_cpuid_check_and_set(cs, HYPERV_FEAT_CRASH);
+    r |= hv_cpuid_check_and_set(cs, HYPERV_FEAT_RESET);
+    r |= hv_cpuid_check_and_set(cs, HYPERV_FEAT_VPINDEX);
+    r |= hv_cpuid_check_and_set(cs, HYPERV_FEAT_RUNTIME);
+    r |= hv_cpuid_check_and_set(cs, HYPERV_FEAT_SYNIC);
+    r |= hv_cpuid_check_and_set(cs, HYPERV_FEAT_STIMER);
+    r |= hv_cpuid_check_and_set(cs, HYPERV_FEAT_FREQUENCIES);
+    r |= hv_cpuid_check_and_set(cs, HYPERV_FEAT_REENLIGHTENMENT);
+    r |= hv_cpuid_check_and_set(cs, HYPERV_FEAT_TLBFLUSH);
+    r |= hv_cpuid_check_and_set(cs, HYPERV_FEAT_EVMCS);
+    r |= hv_cpuid_check_and_set(cs, HYPERV_FEAT_IPI);
+    r |= hv_cpuid_check_and_set(cs, HYPERV_FEAT_STIMER_DIRECT);
 
     /* Additional dependencies not covered by kvm_hyperv_properties[] */
     if (hyperv_feat_enabled(cpu, HYPERV_FEAT_SYNIC) &&
@@ -1315,8 +1319,7 @@  static int hyperv_handle_properties(CPUState *cs,
     env->features[FEAT_HYPERV_EDX] |= HV_CPU_DYNAMIC_PARTITIONING_AVAILABLE;
 
     if (r) {
-        r = -ENOSYS;
-        goto free;
+        return -ENOSYS;
     }
 
     c = &cpuid_ent[cpuid_i++];
@@ -1373,12 +1376,8 @@  static int hyperv_handle_properties(CPUState *cs,
         c->function = HV_CPUID_NESTED_FEATURES;
         c->eax = env->features[FEAT_HV_NESTED_EAX];
     }
-    r = cpuid_i;
-
-free:
-    g_free(cpuid);
 
-    return r;
+    return cpuid_i;
 }
 
 static Error *hv_passthrough_mig_blocker;