[Qemu-devel] [PATCH v4 09/10] cpu: add device_add foo-x86_64-cpu support

[Zhu Guihua]

From: Chen Fan <address@hidden>

Add support to device_add foo-x86_64-cpu, and additional checks of
apic id are added into x86_cpuid_set_apic_id() to avoid duplicate.
Besides, in order to support "device/device_add foo-x86_64-cpu"
which without specified apic id, we assign cpuid_apic_id with a
default broadcast value (0xFFFFFFFF) in initfn, and a new function
get_free_apic_id() to provide a free apid id to cpuid_apic_id if
it still has the default at realize time (e.g. hot add foo-cpu without
a specified apic id) to avoid apic id duplicates.

Thanks very much for Igor's suggestion.

Signed-off-by: Chen Fan <address@hidden>
Signed-off-by: Gu Zheng <address@hidden>
Signed-off-by: Zhu Guihua <address@hidden>
---
 hw/acpi/cpu_hotplug.c |  6 ++++--
 hw/i386/pc.c          |  6 ------
 target-i386/cpu.c     | 48 +++++++++++++++++++++++++++++++++++++++++++++---
 3 files changed, 49 insertions(+), 11 deletions(-)

diff --git a/hw/acpi/cpu_hotplug.c b/hw/acpi/cpu_hotplug.c
index b8ebfad..8e4ed6e 100644
--- a/hw/acpi/cpu_hotplug.c
+++ b/hw/acpi/cpu_hotplug.c
@@ -59,8 +59,10 @@ void acpi_cpu_plug_cb(ACPIREGS *ar, qemu_irq irq,
         return;
     }
 
-    ar->gpe.sts[0] |= ACPI_CPU_HOTPLUG_STATUS;
-    acpi_update_sci(ar, irq);
+    /* Only trigger sci if cpu is hotplugged */
+    if (dev->hotplugged) {
+        acpi_send_gpe_event(ar, irq, ACPI_CPU_HOTPLUG_STATUS);
+    }
 }
 
 void acpi_cpu_hotplug_init(MemoryRegion *parent, Object *owner,
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 500d369..1187e12 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -1637,13 +1637,7 @@ static void pc_cpu_plug(HotplugHandler *hotplug_dev,
     Error *local_err = NULL;
     PCMachineState *pcms = PC_MACHINE(hotplug_dev);
 
-    if (!dev->hotplugged) {
-        goto out;
-    }
-
     if (!pcms->acpi_dev) {
-        error_setg(&local_err,
-                   "cpu hotplug is not enabled: missing acpi device");
         goto out;
     }
 
diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index 028063c..68a6aa4 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -1703,6 +1703,7 @@ static void x86_cpuid_set_apic_id(Object *obj, Visitor 
*v, void *opaque,
     const int64_t max = UINT32_MAX;
     Error *error = NULL;
     int64_t value;
+    X86CPUTopoInfo topo;
 
     if (dev->realized) {
         error_setg(errp, "Attempt to set property '%s' on '%s' after "
@@ -1722,6 +1723,19 @@ static void x86_cpuid_set_apic_id(Object *obj, Visitor 
*v, void *opaque,
         return;
     }
 
+    if (value > x86_cpu_apic_id_from_index(max_cpus - 1)) {
+        error_setg(errp, "CPU with APIC ID %" PRIi64
+                   " is more than MAX APIC ID limits", value);
+        return;
+    }
+
+    x86_topo_ids_from_apic_id(smp_cores, smp_threads, value, &topo);
+    if (topo.smt_id >= smp_threads || topo.core_id >= smp_cores) {
+        error_setg(errp, "CPU with APIC ID %" PRIi64 " does not match "
+                   "topology configuration.", value);
+        return;
+    }
+
     if ((value != cpu->env.cpuid_apic_id) && cpu_exists(value)) {
         error_setg(errp, "CPU with APIC ID %" PRIi64 " exists", value);
         return;
@@ -2166,8 +2180,10 @@ static void x86_cpu_cpudef_class_init(ObjectClass *oc, 
void *data)
 {
     X86CPUDefinition *cpudef = data;
     X86CPUClass *xcc = X86_CPU_CLASS(oc);
+    DeviceClass *dc = DEVICE_CLASS(oc);
 
     xcc->cpu_def = cpudef;
+    dc->cannot_instantiate_with_device_add_yet = false;
 }
 
 static void x86_register_cpudef_type(X86CPUDefinition *def)
@@ -2176,6 +2192,7 @@ static void x86_register_cpudef_type(X86CPUDefinition 
*def)
     TypeInfo ti = {
         .name = typename,
         .parent = TYPE_X86_CPU,
+        .instance_size = sizeof(X86CPU),
         .class_init = x86_cpu_cpudef_class_init,
         .class_data = def,
     };
@@ -2709,11 +2726,28 @@ static void mce_init(X86CPU *cpu)
 }
 
 #ifndef CONFIG_USER_ONLY
+static uint32_t get_free_apic_id(void)
+{
+    int i;
+
+    for (i = 0; i < max_cpus; i++) {
+        uint32_t id = x86_cpu_apic_id_from_index(i);
+
+        if (!cpu_exists(id)) {
+            return id;
+        }
+    }
+
+    return x86_cpu_apic_id_from_index(max_cpus);
+}
+
+#define APIC_ID_NOT_SET (~0U)
+
 static void x86_cpu_apic_create(X86CPU *cpu, Error **errp)
 {
-    CPUX86State *env = &cpu->env;
     APICCommonState *apic;
     const char *apic_type = "apic";
+    uint32_t apic_id;
 
     if (kvm_irqchip_in_kernel()) {
         apic_type = "kvm-apic";
@@ -2729,7 +2763,15 @@ static void x86_cpu_apic_create(X86CPU *cpu, Error 
**errp)
 
     object_property_add_child(OBJECT(cpu), "apic",
                               OBJECT(cpu->apic_state), NULL);
-    qdev_prop_set_uint8(cpu->apic_state, "id", env->cpuid_apic_id);
+
+    apic_id = object_property_get_int(OBJECT(cpu), "apic-id", NULL);
+    if (apic_id == APIC_ID_NOT_SET) {
+        apic_id = get_free_apic_id();
+        object_property_set_int(OBJECT(cpu), apic_id, "apic-id", errp);
+    }
+
+    qdev_prop_set_uint8(cpu->apic_state, "id", apic_id);
+
     /* TODO: convert to link<> */
     apic = APIC_COMMON(cpu->apic_state);
     apic->cpu = cpu;
@@ -2920,7 +2962,7 @@ static void x86_cpu_initfn(Object *obj)
                         NULL, NULL, (void *)cpu->filtered_features, NULL);
 
     cpu->hyperv_spinlock_attempts = HYPERV_SPINLOCK_NEVER_RETRY;
-    env->cpuid_apic_id = x86_cpu_apic_id_from_index(cs->cpu_index);
+    env->cpuid_apic_id = APIC_ID_NOT_SET;
 
     x86_cpu_load_def(cpu, xcc->cpu_def, &error_abort);
 
-- 
1.9.3