Merge remote-tracking branch 'qmp/queue/qmp' into staging

* qmp/queue/qmp:
  build: install qmp-commands.txt
  Add rate limiting of RTC_CHANGE, BALLOON_CHANGE & WATCHDOG events
  Add event notification for guest balloon changes
  Fix some more license versions (GPL2+ instead of GPL2)
  monitor: Fix memory leak with readline completion
  qmp: do not include monitor.h from qapi-types-core.h
  qmp: include monitor.h when needed
  kvm: add missing include files

Makefile

@@ -272,6 +272,7 @@ endif
 install-doc: $(DOCS)
 	$(INSTALL_DIR) "$(DESTDIR)$(qemu_docdir)"
 	$(INSTALL_DATA) qemu-doc.html  qemu-tech.html "$(DESTDIR)$(qemu_docdir)"
+	$(INSTALL_DATA) QMP/qmp-commands.txt "$(DESTDIR)$(qemu_docdir)"
 ifdef CONFIG_POSIX
 	$(INSTALL_DIR) "$(DESTDIR)$(mandir)/man1"
 	$(INSTALL_DATA) qemu.1 qemu-img.1 "$(DESTDIR)$(mandir)/man1"

QMP/qmp-events.txt

@@ -335,3 +335,21 @@ Example:
                "len": 10737418240, "offset": 134217728,
                "speed": 0 },
      "timestamp": { "seconds": 1267061043, "microseconds": 959568 } }
+
+
+BALLOON_CHANGE
+----------
+
+Emitted when the guest changes the actual BALLOON level. This
+value is equivalent to the 'actual' field return by the
+'query-balloon' command
+
+Data:
+
+- "actual": actual level of the guest memory balloon in bytes (json-number)
+
+Example:
+
+{ "event": "BALLOON_CHANGE",
+    "data": { "actual": 944766976 },
+    "timestamp": { "seconds": 1267020223, "microseconds": 435656 } }

balloon.c

@@ -30,6 +30,7 @@
 #include "balloon.h"
 #include "trace.h"
 #include "qmp-commands.h"
+#include "qjson.h"
 
 static QEMUBalloonEvent *balloon_event_fn;
 static QEMUBalloonStatus *balloon_stat_fn;
@@ -80,6 +81,19 @@ static int qemu_balloon_status(BalloonInfo *info)
     return 1;
 }
 
+void qemu_balloon_changed(int64_t actual)
+{
+    QObject *data;
+
+    data = qobject_from_jsonf("{ 'actual': %" PRId64 " }",
+                              actual);
+
+    monitor_protocol_event(QEVENT_BALLOON_CHANGE, data);
+
+    qobject_decref(data);
+}
+
+
 BalloonInfo *qmp_query_balloon(Error **errp)
 {
     BalloonInfo *info;

balloon.h

@@ -24,4 +24,6 @@ int qemu_add_balloon_handler(QEMUBalloonEvent *event_func,
 			     QEMUBalloonStatus *stat_func, void *opaque);
 void qemu_remove_balloon_handler(void *opaque);
 
+void qemu_balloon_changed(int64_t actual);
+
 #endif

hmp.c

@@ -18,6 +18,7 @@
 #include "qemu-option.h"
 #include "qemu-timer.h"
 #include "qmp-commands.h"
+#include "monitor.h"
 
 static void hmp_handle_error(Monitor *mon, Error **errp)
 {

hw/virtio-balloon.c

@@ -146,8 +146,13 @@ static void virtio_balloon_set_config(VirtIODevice *vdev,
 {
     VirtIOBalloon *dev = to_virtio_balloon(vdev);
     struct virtio_balloon_config config;
+    uint32_t oldactual = dev->actual;
     memcpy(&config, config_data, 8);
     dev->actual = le32_to_cpu(config.actual);
+    if (dev->actual != oldactual) {
+        qemu_balloon_changed(ram_size -
+                             (dev->actual << VIRTIO_BALLOON_PFN_SHIFT));
+    }
 }
 
 static uint32_t virtio_balloon_get_features(VirtIODevice *vdev, uint32_t f)

kvm-all.c

@@ -22,6 +22,8 @@
 
 #include "qemu-common.h"
 #include "qemu-barrier.h"
+#include "qemu-option.h"
+#include "qemu-config.h"
 #include "sysemu.h"
 #include "hw/hw.h"
 #include "hw/msi.h"

monitor.c

@@ -66,6 +66,7 @@
 #include "memory.h"
 #include "qmp-commands.h"
 #include "hmp.h"
+#include "qemu-thread.h"
 
 /* for pic/irq_info */
 #if defined(TARGET_SPARC)
@@ -145,6 +146,19 @@ typedef struct MonitorControl {
     int command_mode;
 } MonitorControl;
 
+/*
+ * To prevent flooding clients, events can be throttled. The
+ * throttling is calculated globally, rather than per-Monitor
+ * instance.
+ */
+typedef struct MonitorEventState {
+    MonitorEvent event; /* Event being tracked */
+    int64_t rate;       /* Period over which to throttle. 0 to disable */
+    int64_t last;       /* Time at which event was last emitted */
+    QEMUTimer *timer;   /* Timer for handling delayed events */
+    QObject *data;      /* Event pending delayed dispatch */
+} MonitorEventState;
+
 struct Monitor {
     CharDriverState *chr;
     int mux_out;
@@ -443,9 +457,145 @@ static const char *monitor_event_names[] = {
     [QEVENT_DEVICE_TRAY_MOVED] = "DEVICE_TRAY_MOVED",
     [QEVENT_SUSPEND] = "SUSPEND",
     [QEVENT_WAKEUP] = "WAKEUP",
+    [QEVENT_BALLOON_CHANGE] = "BALLOON_CHANGE",
 };
 QEMU_BUILD_BUG_ON(ARRAY_SIZE(monitor_event_names) != QEVENT_MAX)
 
+MonitorEventState monitor_event_state[QEVENT_MAX];
+QemuMutex monitor_event_state_lock;
+
+/*
+ * Emits the event to every monitor instance
+ */
+static void
+monitor_protocol_event_emit(MonitorEvent event,
+                            QObject *data)
+{
+    Monitor *mon;
+
+    trace_monitor_protocol_event_emit(event, data);
+    QLIST_FOREACH(mon, &mon_list, entry) {
+        if (monitor_ctrl_mode(mon) && qmp_cmd_mode(mon)) {
+            monitor_json_emitter(mon, data);
+        }
+    }
+}
+
+
+/*
+ * Queue a new event for emission to Monitor instances,
+ * applying any rate limiting if required.
+ */
+static void
+monitor_protocol_event_queue(MonitorEvent event,
+                             QObject *data)
+{
+    MonitorEventState *evstate;
+    int64_t now = qemu_get_clock_ns(rt_clock);
+    assert(event < QEVENT_MAX);
+
+    qemu_mutex_lock(&monitor_event_state_lock);
+    evstate = &(monitor_event_state[event]);
+    trace_monitor_protocol_event_queue(event,
+                                       data,
+                                       evstate->rate,
+                                       evstate->last,
+                                       now);
+
+    /* Rate limit of 0 indicates no throttling */
+    if (!evstate->rate) {
+        monitor_protocol_event_emit(event, data);
+        evstate->last = now;
+    } else {
+        int64_t delta = now - evstate->last;
+        if (evstate->data ||
+            delta < evstate->rate) {
+            /* If there's an existing event pending, replace
+             * it with the new event, otherwise schedule a
+             * timer for delayed emission
+             */
+            if (evstate->data) {
+                qobject_decref(evstate->data);
+            } else {
+                int64_t then = evstate->last + evstate->rate;
+                qemu_mod_timer_ns(evstate->timer, then);
+            }
+            evstate->data = data;
+            qobject_incref(evstate->data);
+        } else {
+            monitor_protocol_event_emit(event, data);
+            evstate->last = now;
+        }
+    }
+    qemu_mutex_unlock(&monitor_event_state_lock);
+}
+
+
+/*
+ * The callback invoked by QemuTimer when a delayed
+ * event is ready to be emitted
+ */
+static void monitor_protocol_event_handler(void *opaque)
+{
+    MonitorEventState *evstate = opaque;
+    int64_t now = qemu_get_clock_ns(rt_clock);
+
+    qemu_mutex_lock(&monitor_event_state_lock);
+
+    trace_monitor_protocol_event_handler(evstate->event,
+                                         evstate->data,
+                                         evstate->last,
+                                         now);
+    if (evstate->data) {
+        monitor_protocol_event_emit(evstate->event, evstate->data);
+        qobject_decref(evstate->data);
+        evstate->data = NULL;
+    }
+    evstate->last = now;
+    qemu_mutex_unlock(&monitor_event_state_lock);
+}
+
+
+/*
+ * @event: the event ID to be limited
+ * @rate: the rate limit in milliseconds
+ *
+ * Sets a rate limit on a particular event, so no
+ * more than 1 event will be emitted within @rate
+ * milliseconds
+ */
+static void
+monitor_protocol_event_throttle(MonitorEvent event,
+                                int64_t rate)
+{
+    MonitorEventState *evstate;
+    assert(event < QEVENT_MAX);
+
+    evstate = &(monitor_event_state[event]);
+
+    trace_monitor_protocol_event_throttle(event, rate);
+    evstate->event = event;
+    evstate->rate = rate * SCALE_MS;
+    evstate->timer = qemu_new_timer(rt_clock,
+                                    SCALE_MS,
+                                    monitor_protocol_event_handler,
+                                    evstate);
+    evstate->last = 0;
+    evstate->data = NULL;
+}
+
+
+/* Global, one-time initializer to configure the rate limiting
+ * and initialize state */
+static void monitor_protocol_event_init(void)
+{
+    qemu_mutex_init(&monitor_event_state_lock);
+    /* Limit RTC & BALLOON events to 1 per second */
+    monitor_protocol_event_throttle(QEVENT_RTC_CHANGE, 1000);
+    monitor_protocol_event_throttle(QEVENT_BALLOON_CHANGE, 1000);
+    monitor_protocol_event_throttle(QEVENT_WATCHDOG, 1000);
+}
+
 /**
  * monitor_protocol_event(): Generate a Monitor event
  *
@@ -455,7 +605,6 @@ void monitor_protocol_event(MonitorEvent event, QObject *data)
 {
     QDict *qmp;
     const char *event_name;
-    Monitor *mon;
 
     assert(event < QEVENT_MAX);
 
@@ -470,11 +619,8 @@ void monitor_protocol_event(MonitorEvent event, QObject *data)
         qdict_put_obj(qmp, "data", data);
     }
 
-    QLIST_FOREACH(mon, &mon_list, entry) {
-        if (monitor_ctrl_mode(mon) && qmp_cmd_mode(mon)) {
-            monitor_json_emitter(mon, QOBJECT(qmp));
-        }
-    }
+    trace_monitor_protocol_event(event, event_name, qmp);
+    monitor_protocol_event_queue(event, QOBJECT(qmp));
     QDECREF(qmp);
 }
 
@@ -4570,6 +4716,7 @@ void monitor_init(CharDriverState *chr, int flags)
 
     if (is_first_init) {
         key_timer = qemu_new_timer_ns(vm_clock, release_keys, NULL);
+        monitor_protocol_event_init();
         is_first_init = 0;
     }
 

monitor.h

@@ -41,6 +41,7 @@ typedef enum MonitorEvent {
     QEVENT_DEVICE_TRAY_MOVED,
     QEVENT_SUSPEND,
     QEVENT_WAKEUP,
+    QEVENT_BALLOON_CHANGE,
 
     /* Add to 'monitor_event_names' array in monitor.c when
      * defining new events here */

net/tap.c

@@ -34,6 +34,7 @@
 #include <net/if.h>
 
 #include "net.h"
+#include "monitor.h"
 #include "sysemu.h"
 #include "qemu-char.h"
 #include "qemu-common.h"

qapi/qapi-types-core.h

@@ -16,8 +16,6 @@
 
 #include "qemu-common.h"
 #include "error.h"
-
-/* FIXME this is temporary until we remove middle mode */
-#include "monitor.h"
+#include "qerror.h"
 
 #endif

trace-events

@@ -677,6 +677,11 @@ esp_mem_writeb_cmd_ensel(uint32_t val) "Enable selection (%2.2x)"
 # monitor.c
 handle_qmp_command(void *mon, const char *cmd_name) "mon %p cmd_name \"%s\""
 monitor_protocol_emitter(void *mon) "mon %p"
+monitor_protocol_event(uint32_t event, const char *evname, void *data) "event=%d name \"%s\" data %p"
+monitor_protocol_event_handler(uint32_t event, void *data, uint64_t last, uint64_t now) "event=%d data=%p last=%" PRId64 " now=%" PRId64
+monitor_protocol_event_emit(uint32_t event, void *data) "event=%d data=%p"
+monitor_protocol_event_queue(uint32_t event, void *data, uint64_t rate, uint64_t last, uint64_t now) "event=%d data=%p rate=%" PRId64 " last=%" PRId64 " now=%" PRId64
+monitor_protocol_event_throttle(uint32_t event, uint64_t rate) "event=%d rate=%" PRId64
 
 # hw/opencores_eth.c
 open_eth_mii_write(unsigned idx, uint16_t v) "MII[%02x] <- %04x"