X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fust-app.c;h=b30089dbc2fd6029f590adf8c05752ddda2d3225;hp=b07bf684bcf870c59a2a212712ffec25db037af4;hb=da8734126339713603c25799dcd1dd72726730de;hpb=faa88ea855741f5c356d223011ff4b347576c7d2

diff --git a/src/bin/lttng-sessiond/ust-app.c b/src/bin/lttng-sessiond/ust-app.c
index b07bf684b..b30089dbc 100644
--- a/src/bin/lttng-sessiond/ust-app.c
+++ b/src/bin/lttng-sessiond/ust-app.c
@@ -921,6 +921,28 @@ void delete_ust_app(struct ust_app *app)
 	ht_cleanup_push(app->ust_sessions_objd);
 	ht_cleanup_push(app->ust_objd);
 
+	/*
+	 * This could be NULL if the event notifier setup failed (e.g the app
+	 * was killed or the tracer does not support this feature).
+	 */
+	if (app->event_notifier_group.object) {
+		enum lttng_error_code ret_code;
+		const int event_notifier_read_fd = lttng_pipe_get_readfd(
+				app->event_notifier_group.event_pipe);
+
+		ret_code = notification_thread_command_remove_tracer_event_source(
+				notification_thread_handle,
+				event_notifier_read_fd);
+		if (ret_code != LTTNG_OK) {
+			ERR("Failed to remove application tracer event source from notification thread");
+		}
+
+		ustctl_release_object(sock, app->event_notifier_group.object);
+		free(app->event_notifier_group.object);
+	}
+
+	lttng_pipe_destroy(app->event_notifier_group.event_pipe);
+
 	/*
 	 * Wait until we have deleted the application from the sock hash table
 	 * before closing this socket, otherwise an application could re-use the
@@ -3312,6 +3334,7 @@ error:
 struct ust_app *ust_app_create(struct ust_register_msg *msg, int sock)
 {
 	struct ust_app *lta = NULL;
+	struct lttng_pipe *event_notifier_event_source_pipe = NULL;
 
 	assert(msg);
 	assert(sock >= 0);
@@ -3328,12 +3351,21 @@ struct ust_app *ust_app_create(struct ust_register_msg *msg, int sock)
 		goto error;
 	}
 
+	event_notifier_event_source_pipe = lttng_pipe_open(FD_CLOEXEC);
+	if (!event_notifier_event_source_pipe) {
+		PERROR("Failed to open application event source pipe: '%s' (ppid = %d)",
+				msg->name, msg->ppid);
+		goto error;
+	}
+
 	lta = zmalloc(sizeof(struct ust_app));
 	if (lta == NULL) {
 		PERROR("malloc");
-		goto error;
+		goto error_free_pipe;
 	}
 
+	lta->event_notifier_group.event_pipe = event_notifier_event_source_pipe;
+
 	lta->ppid = msg->ppid;
 	lta->uid = msg->uid;
 	lta->gid = msg->gid;
@@ -3371,8 +3403,12 @@ struct ust_app *ust_app_create(struct ust_register_msg *msg, int sock)
 	lttng_ht_node_init_ulong(&lta->sock_n, (unsigned long) lta->sock);
 
 	CDS_INIT_LIST_HEAD(&lta->teardown_head);
-error:
 	return lta;
+
+error_free_pipe:
+	lttng_pipe_destroy(event_notifier_event_source_pipe);
+error:
+	return NULL;
 }
 
 /*
@@ -3438,6 +3474,61 @@ int ust_app_version(struct ust_app *app)
 	return ret;
 }
 
+/*
+ * Setup the base event notifier group.
+ *
+ * Return 0 on success else a negative value either an errno code or a
+ * LTTng-UST error code.
+ */
+int ust_app_setup_event_notifier_group(struct ust_app *app)
+{
+	int ret;
+	int event_pipe_write_fd;
+	struct lttng_ust_object_data *event_notifier_group = NULL;
+	enum lttng_error_code lttng_ret;
+
+	assert(app);
+
+	/* Get the write side of the pipe. */
+	event_pipe_write_fd = lttng_pipe_get_writefd(
+			app->event_notifier_group.event_pipe);
+
+	pthread_mutex_lock(&app->sock_lock);
+	ret = ustctl_create_event_notifier_group(app->sock,
+			event_pipe_write_fd, &event_notifier_group);
+	pthread_mutex_unlock(&app->sock_lock);
+	if (ret < 0) {
+		if (ret != -LTTNG_UST_ERR_EXITING && ret != -EPIPE) {
+			ERR("Failed to create application event notifier group: ret = %d, app socket fd = %d, event_pipe_write_fd = %d",
+					ret, app->sock, event_pipe_write_fd);
+		} else {
+			DBG("Failed to create application event notifier group (application is dead): app socket fd = %d",
+					app->sock);
+		}
+
+		goto error;
+	}
+
+	lttng_ret = notification_thread_command_add_tracer_event_source(
+			notification_thread_handle,
+			lttng_pipe_get_readfd(app->event_notifier_group.event_pipe),
+			LTTNG_DOMAIN_UST);
+	if (lttng_ret != LTTNG_OK) {
+		ERR("Failed to add tracer event source to notification thread");
+		ret = - 1;
+		goto error;
+	}
+
+	/* Assign handle only when the complete setup is valid. */
+	app->event_notifier_group.object = event_notifier_group;
+	return ret;
+
+error:
+	ustctl_release_object(app->sock, app->event_notifier_group.object);
+	free(app->event_notifier_group.object);
+	return ret;
+}
+
 /*
  * Unregister app by removing it from the global traceable app list and freeing
  * the data struct.