[Qemu-devel] [RFC][PATCH 6/6] i386: implement cpu interface 'cpu_common_unrealizefn'

[Chen Fan]

Implement cpu interface 'cpu_common_unrealizefn' for emiting vcpu-remove
notifier to ACPI, then ACPI could send sci interrupt to OS for hot-remove
vcpu.

Signed-off-by: Chen Fan <chen.fan.f...@cn.fujitsu.com>
---
 hw/i386/pc.c | 19 ++++++++++++++++++-
 qom/cpu.c    | 13 +++++++++++++
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 75fc9bb..9a87ac0 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -960,7 +960,24 @@ void pc_hot_add_cpu(const int64_t id, Error **errp)
 
 void pc_hot_del_cpu(const int64_t id, Error **errp)
 {
-    /* TODO: hot remove VCPU. */
+    CPUState *s = NULL;
+    X86CPU *cpu = NULL;
+    DeviceState *ds = NULL;
+    DeviceClass *dc = NULL;
+
+    s = qemu_get_cpu(id);
+    if (s == NULL) {
+        error_setg(errp, "Unable to find cpu-index: %" PRIi64
+                   ",it non-exists or has been deleted.", id);
+        return;
+    }
+
+    cpu = X86_CPU(s);
+    ds = DEVICE(cpu);
+    dc = DEVICE_GET_CLASS(ds);
+    if (dc->unrealize) {
+        dc->unrealize(ds, errp);
+    }
 }
 
 void pc_cpus_init(const char *cpu_model, DeviceState *icc_bridge)
diff --git a/qom/cpu.c b/qom/cpu.c
index 3439c5d..d2b0c9e 100644
--- a/qom/cpu.c
+++ b/qom/cpu.c
@@ -239,6 +239,18 @@ static void cpu_common_realizefn(DeviceState *dev, Error 
**errp)
     }
 }
 
+static void cpu_common_unrealizefn(DeviceState *dev, Error **errp)
+{
+    CPUNotifier notifier;
+
+    notifier.dev = dev;
+    notifier.type = UNPLUG;
+
+    if (dev->hotplugged) {
+        notifier_list_notify(&cpu_hotplug_notifiers, &notifier);
+     }
+}
+
 static void cpu_common_initfn(Object *obj)
 {
     CPUState *cpu = CPU(obj);
@@ -269,6 +281,7 @@ static void cpu_class_init(ObjectClass *klass, void *data)
     k->gdb_read_register = cpu_common_gdb_read_register;
     k->gdb_write_register = cpu_common_gdb_write_register;
     dc->realize = cpu_common_realizefn;
+    dc->unrealize = cpu_common_unrealizefn;
     dc->no_user = 1;
 }
 
-- 
1.8.1.4