Merge remote-tracking branch 'remotes/mcayland/tags/qemu-sparc.for-upstream-20180820...

[qemu.git] / monitor.c

diff --git a/monitor.c b/monitor.c
index 3c9c97b73f92c0208115c1be09a2d218f622c2be..a1999e396ca04b75c316843f1ae8e82d285ee765 100644 (file)
--- a/monitor.c
+++ b/monitor.c
@@ -290,7 +290,7 @@ static mon_cmd_t info_cmds[];
 
 QmpCommandList qmp_commands, qmp_cap_negotiation_commands;
 
-Monitor *cur_mon;
+__thread Monitor *cur_mon;
 
 static void monitor_command_cb(void *opaque, const char *cmdline,
                                void *readline_opaque);
@@ -633,7 +633,7 @@ static void monitor_qapi_event_handler(void *opaque);
  * applying any rate limiting if required.
  */
 static void
-monitor_qapi_event_queue(QAPIEvent event, QDict *qdict, Error **errp)
+monitor_qapi_event_queue_no_reenter(QAPIEvent event, QDict *qdict)
 {
     MonitorQAPIEventConf *evconf;
     MonitorQAPIEventState *evstate;
@@ -688,6 +688,48 @@ monitor_qapi_event_queue(QAPIEvent event, QDict *qdict, Error **errp)
     qemu_mutex_unlock(&monitor_lock);
 }
 
+static void
+monitor_qapi_event_queue(QAPIEvent event, QDict *qdict, Error **errp)
+{
+    /*
+     * monitor_qapi_event_queue_no_reenter() is not reentrant: it
+     * would deadlock on monitor_lock.  Work around by queueing
+     * events in thread-local storage.
+     * TODO: remove this, make it re-enter safe.
+     */
+    typedef struct MonitorQapiEvent {
+        QAPIEvent event;
+        QDict *qdict;
+        QSIMPLEQ_ENTRY(MonitorQapiEvent) entry;
+    } MonitorQapiEvent;
+    static __thread QSIMPLEQ_HEAD(, MonitorQapiEvent) event_queue;
+    static __thread bool reentered;
+    MonitorQapiEvent *ev;
+
+    if (!reentered) {
+        QSIMPLEQ_INIT(&event_queue);
+    }
+
+    ev = g_new(MonitorQapiEvent, 1);
+    ev->qdict = qobject_ref(qdict);
+    ev->event = event;
+    QSIMPLEQ_INSERT_TAIL(&event_queue, ev, entry);
+    if (reentered) {
+        return;
+    }
+
+    reentered = true;
+
+    while ((ev = QSIMPLEQ_FIRST(&event_queue)) != NULL) {
+        QSIMPLEQ_REMOVE_HEAD(&event_queue, entry);
+        monitor_qapi_event_queue_no_reenter(ev->event, ev->qdict);
+        qobject_unref(ev->qdict);
+        g_free(ev);
+    }
+
+    reentered = false;
+}
+
 /*
  * This function runs evconf->rate ns after sending a throttled
  * event.
@@ -4186,6 +4228,7 @@ static void monitor_qmp_bh_dispatcher(void *data)
     } else {
         assert(req_obj->err);
         rsp = qmp_error_response(req_obj->err);
+        req_obj->err = NULL;
         monitor_qmp_respond(req_obj->mon, rsp, NULL);
         qobject_unref(rsp);
     }
@@ -4223,7 +4266,7 @@ static void handle_qmp_command(JSONMessageParser *parser, GQueue *tokens)
         qdict_del(qdict, "id");
     } /* else will fail qmp_dispatch() */
 
-    if (trace_event_get_state_backends(TRACE_HANDLE_QMP_COMMAND)) {
+    if (req && trace_event_get_state_backends(TRACE_HANDLE_QMP_COMMAND)) {
         QString *req_json = qobject_to_json(req);
         trace_handle_qmp_command(mon, qstring_get_str(req_json));
         qobject_unref(req_json);
@@ -4234,6 +4277,8 @@ static void handle_qmp_command(JSONMessageParser *parser, GQueue *tokens)
         trace_monitor_qmp_cmd_out_of_band(qobject_get_try_str(id)
                                           ?: "");
         monitor_qmp_dispatch(mon, req, id);
+        qobject_unref(req);
+        qobject_unref(id);
         return;
     }