[RFC,qom-cpu,v4,05/10] qmp: add 'cpu-del' command support

diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 832c9b2..40d611e 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -956,6 +956,12 @@  void pc_hot_add_cpu(const int64_t id, Error **errp)
     pc_new_cpu(current_cpu_model, apic_id, icc_bridge, errp);
 }
 
+void pc_hot_del_cpu(const int64_t id, Error **errp)
+{
+    /* TODO: hot remove vCPU. */
+    error_setg(errp, "Hot-remove CPU is not supported.");
+}
+
 void pc_cpus_init(const char *cpu_model, DeviceState *icc_bridge)
 {
     int i;
diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index c6042c7..e7039be 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -337,7 +337,8 @@  static void pc_xen_hvm_init(QEMUMachineInitArgs *args)
 #define PC_I440FX_MACHINE_OPTIONS \
     PC_DEFAULT_MACHINE_OPTIONS, \
     .desc = "Standard PC (i440FX + PIIX, 1996)", \
-    .hot_add_cpu = pc_hot_add_cpu
+    .hot_add_cpu = pc_hot_add_cpu, \
+    .hot_del_cpu = pc_hot_del_cpu
 
 #define PC_I440FX_1_7_MACHINE_OPTIONS PC_I440FX_MACHINE_OPTIONS
 static QEMUMachine pc_i440fx_machine_v1_7 = {
diff --git a/include/hw/boards.h b/include/hw/boards.h
index 5a7ae9f..5934828 100644
--- a/include/hw/boards.h
+++ b/include/hw/boards.h
@@ -20,6 +20,7 @@  typedef void QEMUMachineInitFunc(QEMUMachineInitArgs *args);
 typedef void QEMUMachineResetFunc(void);
 
 typedef void QEMUMachineHotAddCPUFunc(const int64_t id, Error **errp);
+typedef void QEMUMachineHotDelCPUFunc(const int64_t id, Error **errp);
 
 typedef struct QEMUMachine {
     const char *name;
@@ -28,6 +29,7 @@  typedef struct QEMUMachine {
     QEMUMachineInitFunc *init;
     QEMUMachineResetFunc *reset;
     QEMUMachineHotAddCPUFunc *hot_add_cpu;
+    QEMUMachineHotDelCPUFunc *hot_del_cpu;
     BlockInterfaceType block_default_type;
     int max_cpus;
     unsigned int no_serial:1,
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index 6083839..e7f4313 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -96,6 +96,7 @@  void pc_acpi_smi_interrupt(void *opaque, int irq, int level);
 
 void pc_cpus_init(const char *cpu_model, DeviceState *icc_bridge);
 void pc_hot_add_cpu(const int64_t id, Error **errp);
+void pc_hot_del_cpu(const int64_t id, Error **errp);
 void pc_acpi_init(const char *default_dsdt);
 
 PcGuestInfo *pc_guest_info_init(ram_addr_t below_4g_mem_size,
diff --git a/qapi-schema.json b/qapi-schema.json
index 145eca8..e2a47ea 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1479,6 +1479,18 @@ 
 ##
 { 'command': 'cpu-add', 'data': {'id': 'int'} }
 
+# @cpu-del
+
+# Deletes CPU with specified ID
+#
+# @id: ID of CPU to be deleted, valid values [0..max_cpus)
+#
+# Returns: Nothing on success
+#
+# Since 1.7
+##
+{ 'command': 'cpu-del', 'data': {'id': 'int'} }
+
 ##
 # @memsave:
 #
diff --git a/qmp-commands.hx b/qmp-commands.hx
index b17c46e..8f2bfdb 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -411,6 +411,29 @@  Example:
 EQMP
 
     {
+        .name       = "cpu-del",
+        .args_type  = "id:i",
+        .mhandler.cmd_new = qmp_marshal_input_cpu_del,
+    },
+
+SQMP
+cpu-del
+-------
+
+Deletes virtual cpu
+
+Arguments:
+
+- "id": cpu id (json-int)
+
+Example:
+
+-> { "execute": "cpu-del", "arguments": { "id": 2 } }
+<- { "return": {} }
+
+EQMP
+
+    {
         .name       = "memsave",
         .args_type  = "val:l,size:i,filename:s,cpu:i?",
         .mhandler.cmd_new = qmp_marshal_input_memsave,
diff --git a/qmp.c b/qmp.c
index 4c149b3..84dc873 100644
--- a/qmp.c
+++ b/qmp.c
@@ -118,6 +118,15 @@  void qmp_cpu_add(int64_t id, Error **errp)
     }
 }
 
+void qmp_cpu_del(int64_t id, Error **errp)
+{
+    if (current_machine->hot_del_cpu) {
+        current_machine->hot_del_cpu(id, errp);
+    } else {
+        error_setg(errp, "Not supported");
+    }
+}
+
 #ifndef CONFIG_VNC
 /* If VNC support is enabled, the "true" query-vnc command is
    defined in the VNC subsystem */