From 6cdff51fb3043043320d89ec38cf088f8eba1ca2 Mon Sep 17 00:00:00 2001
From: Peter Krempa <pkrempa@redhat.com>
Date: Mon, 27 May 2013 16:08:30 +0200
Subject: [PATCH] qemu: Implement new QMP command for cpu hotplug

This patch implements support for the "cpu-add" QMP command that plugs
CPUs into a live guest. The "cpu-add" command was introduced in QEMU
1.5. For the hotplug to work machine type "pc-i440fx-1.5" is required.

(cherry picked from commit c12b2be5169298708cf727ed9ccd42e9d89a9737)
---
 src/qemu/qemu_monitor_json.c | 37 ++++++++++++++++++++++++++++++++++--
 1 file changed, 35 insertions(+), 2 deletions(-)

diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c
index 6fdd650d88..7f3e0a6012 100644
--- a/src/qemu/qemu_monitor_json.c
+++ b/src/qemu/qemu_monitor_json.c
@@ -2086,9 +2086,42 @@ cleanup:
 int qemuMonitorJSONSetCPU(qemuMonitorPtr mon,
                           int cpu, int online)
 {
-    /* XXX Update to use QMP, if QMP ever adds support for cpu hotplug */
+    int ret = -1;
+    virJSONValuePtr cmd = NULL;
+    virJSONValuePtr reply = NULL;
+
+    if (online) {
+        cmd = qemuMonitorJSONMakeCommand("cpu-add",
+                                         "i:id", cpu,
+                                         NULL);
+    } else {
+        /* offlining is not yet implemented in qmp */
+        goto fallback;
+    }
+    if (!cmd)
+        goto cleanup;
+
+    if ((ret = qemuMonitorJSONCommand(mon, cmd, &reply)) < 0)
+        goto cleanup;
+
+    if (qemuMonitorJSONHasError(reply, "CommandNotFound"))
+        goto fallback;
+    else
+        ret = qemuMonitorJSONCheckError(cmd, reply);
+
+    /* this function has non-standard return values, so adapt it */
+    if (ret == 0)
+        ret = 1;
+
+cleanup:
+    virJSONValueFree(cmd);
+    virJSONValueFree(reply);
+    return ret;
+
+fallback:
     VIR_DEBUG("no QMP support for cpu_set, trying HMP");
-    return qemuMonitorTextSetCPU(mon, cpu, online);
+    ret = qemuMonitorTextSetCPU(mon, cpu, online);
+    goto cleanup;
 }