[Qemu-devel] [RFC] [PATCHv8 11/30] aio / timers: Add a notify callback to QEMUTimerList

[Alex Bligh <alex@alex.org.uk>]

Add a notify pointer to QEMUTimerList so it knows what to notify
on a timer change.

Signed-off-by: Alex Bligh <alex@alex.org.uk>
---
 async.c              |    7 ++++++-
 include/qemu/timer.h |   35 ++++++++++++++++++++++++++++++++---
 qemu-timer.c         |   24 ++++++++++++++++++++++--
 3 files changed, 60 insertions(+), 6 deletions(-)

diff --git a/async.c b/async.c
index 99fb5a8..2051921 100644
--- a/async.c
+++ b/async.c
@@ -234,6 +234,11 @@ void aio_notify(AioContext *ctx)
     event_notifier_set(&ctx->notifier);
 }
 
+static void aio_timerlist_notify(void *opaque)
+{
+    aio_notify(opaque);
+}
+
 AioContext *aio_context_new(void)
 {
     AioContext *ctx;
@@ -245,7 +250,7 @@ AioContext *aio_context_new(void)
     aio_set_event_notifier(ctx, &ctx->notifier, 
                            (EventNotifierHandler *)
                            event_notifier_test_and_clear, NULL);
-    timerlistgroup_init(ctx->tlg);
+    timerlistgroup_init(ctx->tlg, aio_timerlist_notify, ctx);
 
     return ctx;
 }
diff --git a/include/qemu/timer.h b/include/qemu/timer.h
index 3b46f60..07e6d9e 100644
--- a/include/qemu/timer.h
+++ b/include/qemu/timer.h
@@ -54,6 +54,7 @@ typedef struct QEMUClock QEMUClock;
 typedef struct QEMUTimerList QEMUTimerList;
 typedef QEMUTimerList *QEMUTimerListGroup[QEMU_CLOCK_MAX];
 typedef void QEMUTimerCB(void *opaque);
+typedef void QEMUTimerListNotifyCB(void *opaque);
 
 extern QEMUTimerListGroup main_loop_tlg;
 extern QEMUClock *qemu_clocks[QEMU_CLOCK_MAX];
@@ -213,13 +214,41 @@ QEMUClock *timerlist_get_clock(QEMUTimerList *timer_list);
 bool timerlist_run_timers(QEMUTimerList *timer_list);
 
 /**
+ * timerlist_set_notify_cb:
+ * @timer_list: the timer list to use
+ * @cb: the callback to call on notification
+ * @opaque: the opaque pointer to pass to the callback
+ *
+ * Set the notify callback for a timer list. The notifier
+ * callback is called when the clock is reenabled or a timer
+ * on the list is modified.
+ */
+void timerlist_set_notify_cb(QEMUTimerList *timer_list,
+                             QEMUTimerListNotifyCB *cb, void *opaque);
+
+/**
+ * timerlist_notify:
+ * @timer_list: the timer list to use
+ *
+ * call the notifier callback associated with the timer list.
+ */
+void timerlist_notify(QEMUTimerList *timer_list);
+
+/**
  * timerlistgroup_init:
  * @tlg: the timer list group
+ * @cb: the callback to call when a notify is required
+ * @opaque: the opaque pointer to be passed to the callback.
  *
  * Initialise a timer list group. This must already be
- * allocated in memory and zeroed.
- */
-void timerlistgroup_init(QEMUTimerListGroup tlg);
+ * allocated in memory and zeroed. The notifier callback is
+ * called whenever a clock in the timer list group is
+ * reenabled or whenever a timer associated with any timer
+ * list is modified. If @cb is specified as null, qemu_notify()
+ * is used instead.
+ */
+void timerlistgroup_init(QEMUTimerListGroup tlg,
+                         QEMUTimerListNotifyCB *cb, void *opaque);
 
 /**
  * timerlistgroup_deinit:
diff --git a/qemu-timer.c b/qemu-timer.c
index e151d24..14cb433 100644
--- a/qemu-timer.c
+++ b/qemu-timer.c
@@ -73,6 +73,8 @@ struct QEMUTimerList {
     QEMUClock *clock;
     QEMUTimer *active_timers;
     QLIST_ENTRY(QEMUTimerList) list;
+    QEMUTimerListNotifyCB *notify_cb;
+    void *notify_opaque;
 };
 
 struct QEMUTimer {
@@ -394,6 +396,22 @@ QEMUTimerList *qemu_clock_get_main_loop_timerlist(QEMUClock *clock)
     return clock->main_loop_timerlist;
 }
 
+void timerlist_set_notify_cb(QEMUTimerList *timer_list,
+                             QEMUTimerListNotifyCB *cb, void *opaque)
+{
+    timer_list->notify_cb = cb;
+    timer_list->notify_opaque = opaque;
+}
+
+void timerlist_notify(QEMUTimerList *timer_list)
+{
+    if (timer_list->notify_cb) {
+        timer_list->notify_cb(timer_list->notify_opaque);
+    } else {
+        qemu_notify_event();
+    }
+}
+
 /* Transition function to convert a nanosecond timeout to ms
  * This is used where a system does not support ppoll
  */
@@ -518,7 +536,7 @@ void qemu_mod_timer_ns(QEMUTimer *ts, int64_t expire_time)
         /* Interrupt execution to force deadline recalculation.  */
         qemu_clock_warp(ts->timer_list->clock);
         if (use_icount) {
-            qemu_notify_event();
+            timerlist_notify(ts->timer_list);
         }
     }
 }
@@ -576,11 +594,13 @@ bool qemu_run_timers(QEMUClock *clock)
     return timerlist_run_timers(clock->main_loop_timerlist);
 }
 
-void timerlistgroup_init(QEMUTimerListGroup tlg)
+void timerlistgroup_init(QEMUTimerListGroup tlg,
+                         QEMUTimerListNotifyCB *cb, void *opaque)
 {
     QEMUClockType type;
     for (type = 0; type < QEMU_CLOCK_MAX; type++) {
         tlg[type] = timerlist_new(type);
+        timerlist_set_notify_cb(tlg[type], cb, opaque);
     }
 }
 
-- 
1.7.9.5