[libvirt] [libvirt-glib] RFC: delay event handle freeing to avoid dead lock

30 Sep 2011

Can be reproduced with the updated test.
---
 examples/conn-test.c              |   20 +++++++++++++++-----
 libvirt-glib/libvirt-glib-event.c |   17 +++++++++++++----
 2 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/examples/conn-test.c b/examples/conn-test.c
index 08045a4..8ea5ad7 100644
--- a/examples/conn-test.c
+++ b/examples/conn-test.c
@@ -31,12 +31,19 @@ do_connection_open(GObject *source,
 {
     GVirConnection *conn = GVIR_CONNECTION(source);
     GError *err = NULL;
-    GMainLoop *loop = opaque;
 
     if (!gvir_connection_open_finish(conn, res, &err)) {
         g_error("%s", err->message);
     }
     g_print("Connected to libvirt\n");
+    g_object_unref(conn);
+}
+
+static void quit(gpointer data,
+                 GObject *where_the_object_was)
+{
+    GMainLoop *loop = data;
+
     g_main_loop_quit(loop);
 }
 
@@ -47,19 +54,22 @@ int main(int argc, char **argv)
 
     gvir_init_object(&argc, &argv);
 
-    if (argc != 2)
+    if (argc != 2) {
         g_error("syntax: %s URI", argv[0]);
-
-    conn = gvir_connection_new(argv[1]);
+        return 1;
+    }
 
     loop = g_main_loop_new(g_main_context_default(),
                            TRUE);
 
-    gvir_connection_open_async(conn, NULL, do_connection_open, loop);
+    conn = gvir_connection_new(argv[1]);
+    g_object_weak_ref(G_OBJECT(conn), quit, loop);
+
     gvir_connection_open_async(conn, NULL, do_connection_open, loop);
 
     g_main_loop_run(loop);
 
+
     return 0;
 }
 
diff --git a/libvirt-glib/libvirt-glib-event.c b/libvirt-glib/libvirt-glib-event.c
index a785c93..8b1bddf 100644
--- a/libvirt-glib/libvirt-glib-event.c
+++ b/libvirt-glib/libvirt-glib-event.c
@@ -195,6 +195,18 @@ cleanup:
     g_mutex_unlock(eventlock);
 }
 
+static gboolean
+_handle_remove(gpointer data)
+{
+    struct gvir_event_handle *h = data;
+
+    if (h->ff)
+        (h->ff)(h->opaque);
+    free(h);
+
+    return FALSE;
+}
+
 static int
 gvir_event_handle_remove(int watch)
 {
@@ -217,10 +229,7 @@ gvir_event_handle_remove(int watch)
     g_source_remove(data->source);
     data->source = 0;
     data->events = 0;
-    if (data->ff)
-        (data->ff)(data->opaque);
-    free(data);
-
+    g_idle_add(_handle_remove, data);
     ret = 0;
 
 cleanup:
-- 
1.7.6.2

    

Marc-André Lureau

Daniel P. Berrange

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participants (2)