X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fust-app.c;h=679cace8a79063a07368163b46d7def48704f7f0;hb=a78af745624dfc8bfe90748a1730fecbb4677a17;hp=98ea50fdb250a6f0f89b2c73240eb7dea4df05d9;hpb=5c3c99d75ba81b265ffc4d41a1f27cf926b7157a;p=lttng-tools.git

diff --git a/src/bin/lttng-sessiond/ust-app.c b/src/bin/lttng-sessiond/ust-app.c
index 98ea50fdb..679cace8a 100644
--- a/src/bin/lttng-sessiond/ust-app.c
+++ b/src/bin/lttng-sessiond/ust-app.c
@@ -155,7 +155,7 @@ void delete_ust_app_event(int sock, struct ust_app_event *ua_event)
  * this function.
  */
 static
-void delete_ust_app_stream(int sock, struct ltt_ust_stream *stream)
+void delete_ust_app_stream(int sock, struct ust_app_stream *stream)
 {
 	if (stream->obj) {
 		ustctl_release_object(sock, stream->obj);
@@ -176,7 +176,7 @@ void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan)
 	struct lttng_ht_iter iter;
 	struct ust_app_event *ua_event;
 	struct ust_app_ctx *ua_ctx;
-	struct ltt_ust_stream *stream, *stmp;
+	struct ust_app_stream *stream, *stmp;
 
 	/* Wipe stream */
 	cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
@@ -367,7 +367,13 @@ struct ust_app_channel *alloc_ust_app_channel(char *name,
 
 	/* Copy attributes */
 	if (attr) {
-		memcpy(&ua_chan->attr, attr, sizeof(ua_chan->attr));
+		/* Translate from lttng_ust_channel to lttng_ust_channel_attr.*/
+		ua_chan->attr.subbuf_size = attr->subbuf_size;
+		ua_chan->attr.num_subbuf = attr->num_subbuf;
+		ua_chan->attr.overwrite = attr->overwrite;
+		ua_chan->attr.switch_timer_interval = attr->switch_timer_interval;
+		ua_chan->attr.read_timer_interval = attr->read_timer_interval;
+		ua_chan->attr.output = attr->output;
 	}
 
 	DBG3("UST app channel %s allocated", ua_chan->name);
@@ -378,6 +384,28 @@ error:
 	return NULL;
 }
 
+/*
+ * Allocate and initialize a UST app stream.
+ *
+ * Return newly allocated stream pointer or NULL on error.
+ */
+static struct ust_app_stream *alloc_ust_app_stream(void)
+{
+	struct ust_app_stream *stream = NULL;
+
+	stream = zmalloc(sizeof(*stream));
+	if (stream == NULL) {
+		PERROR("zmalloc ust app stream");
+		goto error;
+	}
+
+	/* Zero could be a valid value for a handle so flag it to -1. */
+	stream->handle = -1;
+
+error:
+	return stream;
+}
+
 /*
  * Alloc new UST app event.
  */
@@ -526,7 +554,7 @@ int create_ust_channel_context(struct ust_app_channel *ua_chan,
 {
 	int ret;
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	ret = ustctl_add_context(app->sock, &ua_ctx->ctx,
 			ua_chan->obj, &ua_ctx->obj);
@@ -539,7 +567,7 @@ int create_ust_channel_context(struct ust_app_channel *ua_chan,
 	DBG2("UST app context created successfully for channel %s", ua_chan->name);
 
 error:
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return ret;
 }
 
@@ -552,7 +580,7 @@ int set_ust_event_filter(struct ust_app_event *ua_event,
 {
 	int ret;
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	if (!ua_event->filter) {
 		ret = 0;
@@ -568,7 +596,7 @@ int set_ust_event_filter(struct ust_app_event *ua_event,
 	DBG2("UST filter set successfully for event %s", ua_event->name);
 
 error:
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return ret;
 }
 
@@ -580,7 +608,7 @@ static int disable_ust_event(struct ust_app *app,
 {
 	int ret;
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	ret = ustctl_disable(app->sock, ua_event->obj);
 	if (ret < 0) {
@@ -594,7 +622,7 @@ static int disable_ust_event(struct ust_app *app,
 			ua_event->attr.name, app->pid);
 
 error:
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return ret;
 }
 
@@ -606,7 +634,7 @@ static int disable_ust_channel(struct ust_app *app,
 {
 	int ret;
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	ret = ustctl_disable(app->sock, ua_chan->obj);
 	if (ret < 0) {
@@ -620,7 +648,7 @@ static int disable_ust_channel(struct ust_app *app,
 			ua_chan->name, app->pid);
 
 error:
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return ret;
 }
 
@@ -632,7 +660,7 @@ static int enable_ust_channel(struct ust_app *app,
 {
 	int ret;
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	ret = ustctl_enable(app->sock, ua_chan->obj);
 	if (ret < 0) {
@@ -648,7 +676,7 @@ static int enable_ust_channel(struct ust_app *app,
 			ua_chan->name, app->pid);
 
 error:
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return ret;
 }
 
@@ -660,7 +688,7 @@ static int enable_ust_event(struct ust_app *app,
 {
 	int ret;
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	ret = ustctl_enable(app->sock, ua_event->obj);
 	if (ret < 0) {
@@ -674,7 +702,7 @@ static int enable_ust_event(struct ust_app *app,
 			ua_event->attr.name, app->pid);
 
 error:
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return ret;
 }
 
@@ -687,7 +715,7 @@ static int open_ust_metadata(struct ust_app *app,
 	int ret;
 	struct lttng_ust_channel_attr uattr;
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	uattr.overwrite = ua_sess->metadata->attr.overwrite;
 	uattr.subbuf_size = ua_sess->metadata->attr.subbuf_size;
@@ -716,19 +744,19 @@ static int open_ust_metadata(struct ust_app *app,
 	ua_sess->metadata->handle = ua_sess->metadata->obj->handle;
 
 error:
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return ret;
 }
 
 /*
- * Create stream onto the UST tracer for a UST session.
+ * Create metadata stream onto the UST tracer for a given session.
  */
-static int create_ust_stream(struct ust_app *app,
+static int create_ust_metadata_stream(struct ust_app *app,
 		struct ust_app_session *ua_sess)
 {
 	int ret;
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	/* We are going to receive 2 fds, we need to reserve them. */
 	ret = lttng_fd_get(LTTNG_FD_APPS, 2);
@@ -739,12 +767,73 @@ static int create_ust_stream(struct ust_app *app,
 	ret = ustctl_create_stream(app->sock, ua_sess->metadata->obj,
 			&ua_sess->metadata->stream_obj);
 	if (ret < 0) {
+		lttng_fd_put(LTTNG_FD_APPS, 2);
 		ERR("UST create metadata stream failed");
 		goto error;
 	}
 
 error:
-	health_code_update(&health_thread_cmd);
+	health_code_update();
+	return ret;
+}
+
+/*
+ * Create stream onto the UST tracer for a given channel.
+ *
+ * Return -ENOENT if no more stream is available for this channel.
+ * On success, return 0.
+ * On error, return a negative value.
+ */
+static int create_ust_stream(struct ust_app *app,
+		struct ust_app_channel *ua_chan, struct ust_app_stream *stream)
+{
+	int ret;
+
+	assert(app);
+	assert(ua_chan);
+	assert(ua_chan->obj);
+	assert(stream);
+
+	health_code_update();
+
+	/* We are going to receive 2 fds, we need to reserve them. */
+	ret = lttng_fd_get(LTTNG_FD_APPS, 2);
+	if (ret < 0) {
+		ERR("Exhausted number of available FD on stream creation");
+		/* Just to make sure we never return -ENOENT. */
+		ret = -1;
+		goto error;
+	}
+
+	/*
+	 * Set the stream name before creating it. On error, we don't have to
+	 * delete it on the tracer side.
+	 */
+	ret = snprintf(stream->name, sizeof(stream->name), "%s_%u",
+			ua_chan->name, ua_chan->streams.count);
+	if (ret < 0) {
+		/* Without the stream name we can't continue using it. */
+		PERROR("snprintf UST create stream");
+		/* Just to make sure we never return -ENOENT. */
+		ret = -1;
+		goto error;
+	}
+
+	ret = ustctl_create_stream(app->sock, ua_chan->obj, &stream->obj);
+	if (ret < 0) {
+		lttng_fd_put(LTTNG_FD_APPS, 2);
+		/* Indicates that there is no more stream for that channel. */
+		if (ret != -LTTNG_UST_ERR_NOENT) {
+			ERR("UST create metadata stream failed (ret: %d)", ret);
+		}
+		goto error;
+	}
+
+	/* Set stream handle with the returned value. */
+	stream->handle = stream->obj->handle;
+
+error:
+	health_code_update();
 	return ret;
 }
 
@@ -756,9 +845,7 @@ static int create_ust_channel(struct ust_app *app,
 {
 	int ret;
 
-	health_code_update(&health_thread_cmd);
-
-	/* TODO: remove cast and use lttng-ust-abi.h */
+	health_code_update();
 
 	/* We are going to receive 2 fds, we need to reserve them. */
 	ret = lttng_fd_get(LTTNG_FD_APPS, 2);
@@ -767,10 +854,10 @@ static int create_ust_channel(struct ust_app *app,
 		goto error;
 	}
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
-	ret = ustctl_create_channel(app->sock, ua_sess->handle,
-			(struct lttng_ust_channel_attr *)&ua_chan->attr, &ua_chan->obj);
+	ret = ustctl_create_channel(app->sock, ua_sess->handle, &ua_chan->attr,
+			&ua_chan->obj);
 	if (ret < 0) {
 		ERR("Creating channel %s for app (pid: %d, sock: %d) "
 				"and session handle %d with ret %d",
@@ -785,7 +872,7 @@ static int create_ust_channel(struct ust_app *app,
 	DBG2("UST app channel %s created successfully for pid:%d and sock:%d",
 			ua_chan->name, app->pid, app->sock);
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	/* If channel is not enabled, disable it on the tracer */
 	if (!ua_chan->enabled) {
@@ -796,7 +883,7 @@ static int create_ust_channel(struct ust_app *app,
 	}
 
 error:
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return ret;
 }
 
@@ -809,7 +896,7 @@ int create_ust_event(struct ust_app *app, struct ust_app_session *ua_sess,
 {
 	int ret = 0;
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	/* Create UST event on tracer */
 	ret = ustctl_create_event(app->sock, &ua_event->attr, ua_chan->obj,
@@ -825,7 +912,7 @@ int create_ust_event(struct ust_app *app, struct ust_app_session *ua_sess,
 	DBG2("UST app event %s created successfully for pid:%d",
 			ua_event->attr.name, app->pid);
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	/* Set filter if one is present. */
 	if (ua_event->filter) {
@@ -860,7 +947,7 @@ int create_ust_event(struct ust_app *app, struct ust_app_session *ua_sess,
 	}
 
 error:
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return ret;
 }
 
@@ -1030,17 +1117,28 @@ error:
 }
 
 /*
- * Create a UST session onto the tracer of app and add it the session
- * hashtable.
+ * Create a session on the tracer side for the given app.
+ *
+ * On success, ua_sess_ptr is populated with the session pointer or else left
+ * untouched. If the session was created, is_created is set to 1. On error,
+ * it's left untouched. Note that ua_sess_ptr is mandatory but is_created can
+ * be NULL.
  *
- * Return ust app session or NULL on error.
+ * Returns 0 on success or else a negative code which is either -ENOMEM or
+ * -ENOTCONN which is the default code if the ustctl_create_session fails.
  */
-static struct ust_app_session *create_ust_app_session(
-		struct ltt_ust_session *usess, struct ust_app *app)
+static int create_ust_app_session(struct ltt_ust_session *usess,
+		struct ust_app *app, struct ust_app_session **ua_sess_ptr,
+		int *is_created)
 {
+	int ret, created = 0;
 	struct ust_app_session *ua_sess;
 
-	health_code_update(&health_thread_cmd);
+	assert(usess);
+	assert(app);
+	assert(ua_sess_ptr);
+
+	health_code_update();
 
 	ua_sess = lookup_session_by_app(usess, app);
 	if (ua_sess == NULL) {
@@ -1049,23 +1147,28 @@ static struct ust_app_session *create_ust_app_session(
 		ua_sess = alloc_ust_app_session();
 		if (ua_sess == NULL) {
 			/* Only malloc can failed so something is really wrong */
-			goto end;
+			ret = -ENOMEM;
+			goto error;
 		}
 		shadow_copy_session(ua_sess, usess, app);
+		created = 1;
 	}
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	if (ua_sess->handle == -1) {
-		int ret;
-
 		ret = ustctl_create_session(app->sock);
 		if (ret < 0) {
 			ERR("Creating session for app pid %d", app->pid);
 			delete_ust_app_session(-1, ua_sess);
-			/* This means that the tracer is gone... */
-			ua_sess = (void*) -1UL;
-			goto end;
+			if (ret != -ENOMEM) {
+				/*
+				 * Tracer is probably gone or got an internal error so let's
+				 * behave like it will soon unregister or not usable.
+				 */
+				ret = -ENOTCONN;
+			}
+			goto error;
 		}
 
 		ua_sess->handle = ret;
@@ -1077,9 +1180,16 @@ static struct ust_app_session *create_ust_app_session(
 		DBG2("UST app session created successfully with handle %d", ret);
 	}
 
-end:
-	health_code_update(&health_thread_cmd);
-	return ua_sess;
+	*ua_sess_ptr = ua_sess;
+	if (is_created) {
+		*is_created = created;
+	}
+	/* Everything went well. */
+	ret = 0;
+
+error:
+	health_code_update();
+	return ret;
 }
 
 /*
@@ -1352,13 +1462,13 @@ static int create_ust_app_metadata(struct ust_app_session *ua_sess,
 
 	/* Open UST metadata stream */
 	if (ua_sess->metadata->stream_obj == NULL) {
-		ret = create_ust_stream(app, ua_sess);
+		ret = create_ust_metadata_stream(app, ua_sess);
 		if (ret < 0) {
 			goto error;
 		}
 
 		ret = snprintf(ua_sess->metadata->pathname, PATH_MAX,
-				"%s/metadata", ua_sess->path);
+				"%s/" DEFAULT_METADATA_NAME, ua_sess->path);
 		if (ret < 0) {
 			PERROR("asprintf UST create stream");
 			goto error;
@@ -1604,7 +1714,7 @@ int ust_app_list_events(struct lttng_event **events)
 	cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
 		struct lttng_ust_tracepoint_iter uiter;
 
-		health_code_update(&health_thread_cmd);
+		health_code_update();
 
 		if (!app->compatible) {
 			/*
@@ -1622,7 +1732,7 @@ int ust_app_list_events(struct lttng_event **events)
 
 		while ((ret = ustctl_tracepoint_list_get(app->sock, handle,
 					&uiter)) != -LTTNG_UST_ERR_NOENT) {
-			health_code_update(&health_thread_cmd);
+			health_code_update();
 			if (count >= nbmem) {
 				/* In case the realloc fails, we free the memory */
 				void *ptr;
@@ -1656,7 +1766,7 @@ int ust_app_list_events(struct lttng_event **events)
 rcu_error:
 	rcu_read_unlock();
 error:
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return ret;
 }
 
@@ -1684,7 +1794,7 @@ int ust_app_list_event_fields(struct lttng_event_field **fields)
 	cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
 		struct lttng_ust_field_iter uiter;
 
-		health_code_update(&health_thread_cmd);
+		health_code_update();
 
 		if (!app->compatible) {
 			/*
@@ -1702,7 +1812,7 @@ int ust_app_list_event_fields(struct lttng_event_field **fields)
 
 		while ((ret = ustctl_tracepoint_field_list_get(app->sock, handle,
 					&uiter)) != -LTTNG_UST_ERR_NOENT) {
-			health_code_update(&health_thread_cmd);
+			health_code_update();
 			if (count >= nbmem) {
 				/* In case the realloc fails, we free the memory */
 				void *ptr;
@@ -1741,7 +1851,7 @@ int ust_app_list_event_fields(struct lttng_event_field **fields)
 rcu_error:
 	rcu_read_unlock();
 error:
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return ret;
 }
 
@@ -2030,10 +2140,10 @@ int ust_app_disable_all_event_glb(struct ltt_ust_session *usess,
 int ust_app_create_channel_glb(struct ltt_ust_session *usess,
 		struct ltt_ust_channel *uchan)
 {
-	int ret = 0;
+	int ret = 0, created;
 	struct lttng_ht_iter iter;
 	struct ust_app *app;
-	struct ust_app_session *ua_sess;
+	struct ust_app_session *ua_sess = NULL;
 
 	/* Very wrong code flow */
 	assert(usess);
@@ -2058,25 +2168,34 @@ int ust_app_create_channel_glb(struct ltt_ust_session *usess,
 		 * that if session exist, it will simply return a pointer to the ust
 		 * app session.
 		 */
-		ua_sess = create_ust_app_session(usess, app);
-		if (ua_sess == NULL) {
-			/* The malloc() failed. */
-			ret = -ENOMEM;
-			goto error_rcu_unlock;
-		} else if (ua_sess == (void *) -1UL) {
-			/*
-			 * The application's socket is not valid. Either a bad socket or a
-			 * timeout on it. We can't inform yet the caller that for a
-			 * specific app, the session failed so we continue here.
-			 */
-			continue;
+		ret = create_ust_app_session(usess, app, &ua_sess, &created);
+		if (ret < 0) {
+			switch (ret) {
+			case -ENOTCONN:
+				/*
+				 * The application's socket is not valid. Either a bad socket
+				 * or a timeout on it. We can't inform the caller that for a
+				 * specific app, the session failed so lets continue here.
+				 */
+				continue;
+			case -ENOMEM:
+			default:
+				goto error_rcu_unlock;
+			}
 		}
+		assert(ua_sess);
 
 		/* Create channel onto application. We don't need the chan ref. */
 		ret = create_ust_app_channel(ua_sess, uchan, app, NULL);
-		if (ret < 0 && ret == -ENOMEM) {
-			/* No more memory is a fatal error. Stop right now. */
-			goto error_rcu_unlock;
+		if (ret < 0) {
+			if (ret == -ENOMEM) {
+				/* No more memory is a fatal error. Stop right now. */
+				goto error_rcu_unlock;
+			}
+			/* Cleanup the created session if it's the case. */
+			if (created) {
+				delete_ust_app_session(app->sock, ua_sess);
+			}
 		}
 	}
 
@@ -2221,7 +2340,7 @@ int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
 	struct lttng_ht_iter iter;
 	struct ust_app_session *ua_sess;
 	struct ust_app_channel *ua_chan;
-	struct ltt_ust_stream *ustream;
+	struct ust_app_stream *ustream;
 	struct consumer_socket *socket;
 
 	DBG("Starting tracing for ust app pid %d", app->pid);
@@ -2269,53 +2388,37 @@ int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
 		/* Create all streams */
 		while (1) {
 			/* Create UST stream */
-			ustream = zmalloc(sizeof(*ustream));
+			ustream = alloc_ust_app_stream();
 			if (ustream == NULL) {
-				PERROR("zmalloc ust stream");
-				goto error_rcu_unlock;
-			}
-
-			/* We are going to receive 2 fds, we need to reserve them. */
-			ret = lttng_fd_get(LTTNG_FD_APPS, 2);
-			if (ret < 0) {
-				ERR("Exhausted number of available FD upon stream create");
-				free(ustream);
 				goto error_rcu_unlock;
 			}
 
-			health_code_update(&health_thread_cmd);
+			health_code_update();
 
-			ret = ustctl_create_stream(app->sock, ua_chan->obj,
-					&ustream->obj);
+			ret = create_ust_stream(app, ua_chan, ustream);
 			if (ret < 0) {
-				/* Got all streams */
-				lttng_fd_put(LTTNG_FD_APPS, 2);
+				/* Free unused memory after this point. */
 				free(ustream);
+				if (ret == -LTTNG_UST_ERR_NOENT) {
+					/* Got all streams. Continue normal execution. */
+					break;
+				}
+				/* Error at this point. Stop everything. */
 				ret = LTTNG_ERR_UST_STREAM_FAIL;
-				break;
+				goto error_rcu_unlock;
 			}
-			ustream->handle = ustream->obj->handle;
 
-			health_code_update(&health_thread_cmd);
+			health_code_update();
 
-			/* Order is important */
+			/* Order is important this is why a list is used. */
 			cds_list_add_tail(&ustream->list, &ua_chan->streams.head);
-			ret = snprintf(ustream->name, sizeof(ustream->name), "%s_%u",
-					ua_chan->name, ua_chan->streams.count);
 			ua_chan->streams.count++;
-			if (ret < 0) {
-				PERROR("asprintf UST create stream");
-				/*
-				 * XXX what should we do here with the
-				 * stream ?
-				 */
-				continue;
-			}
+
 			DBG2("UST stream %d ready (handle: %d)", ua_chan->streams.count,
 					ustream->handle);
 		}
 
-		health_code_update(&health_thread_cmd);
+		health_code_update();
 	}
 
 	switch (app->bits_per_long) {
@@ -2344,7 +2447,7 @@ int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
 		goto error_rcu_unlock;
 	}
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 skip_setup:
 	/* This start the UST tracing */
@@ -2357,19 +2460,19 @@ skip_setup:
 	/* Indicate that the session has been started once */
 	ua_sess->started = 1;
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	/* Quiescent wait after starting trace */
 	ustctl_wait_quiescent(app->sock);
 
 end:
 	rcu_read_unlock();
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return 0;
 
 error_rcu_unlock:
 	rcu_read_unlock();
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return -1;
 }
 
@@ -2406,7 +2509,7 @@ int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app)
 		goto error_rcu_unlock;
 	}
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	/* This inhibits UST tracing */
 	ret = ustctl_stop_session(app->sock, ua_sess->handle);
@@ -2415,17 +2518,17 @@ int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app)
 		goto error_rcu_unlock;
 	}
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	/* Quiescent wait after stopping trace */
 	ustctl_wait_quiescent(app->sock);
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	/* Flushing buffers */
 	cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
 			node.node) {
-		health_code_update(&health_thread_cmd);
+		health_code_update();
 		ret = ustctl_sock_flush_buffer(app->sock, ua_chan->obj);
 		if (ret < 0) {
 			ERR("UST app PID %d channel %s flush failed with ret %d",
@@ -2435,7 +2538,7 @@ int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app)
 		}
 	}
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	/* Flush all buffers before stopping */
 	ret = ustctl_sock_flush_buffer(app->sock, ua_sess->metadata->obj);
@@ -2446,12 +2549,12 @@ int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app)
 
 end:
 	rcu_read_unlock();
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return 0;
 
 error_rcu_unlock:
 	rcu_read_unlock();
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return -1;
 }
 
@@ -2491,10 +2594,10 @@ static int destroy_trace(struct ltt_ust_session *usess, struct ust_app *app)
 	obj.shm_fd = -1;
 	obj.wait_fd = -1;
 	obj.memory_map_size = 0;
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	ustctl_release_object(app->sock, &obj);
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	delete_ust_app_session(app->sock, ua_sess);
 
 	/* Quiescent wait after stopping trace */
@@ -2502,7 +2605,7 @@ static int destroy_trace(struct ltt_ust_session *usess, struct ust_app *app)
 
 end:
 	rcu_read_unlock();
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return 0;
 }
 
@@ -2592,7 +2695,7 @@ void ust_app_global_update(struct ltt_ust_session *usess, int sock)
 	int ret = 0;
 	struct lttng_ht_iter iter, uiter, iter_ctx;
 	struct ust_app *app;
-	struct ust_app_session *ua_sess;
+	struct ust_app_session *ua_sess = NULL;
 	struct ust_app_channel *ua_chan;
 	struct ust_app_event *ua_event;
 	struct ust_app_ctx *ua_ctx;
@@ -2614,11 +2717,12 @@ void ust_app_global_update(struct ltt_ust_session *usess, int sock)
 		goto error;
 	}
 
-	ua_sess = create_ust_app_session(usess, app);
-	if (ua_sess == NULL || ua_sess == (void *) -1UL) {
-		/* Tracer is gone for this session and has been freed */
+	ret = create_ust_app_session(usess, app, &ua_sess, NULL);
+	if (ret < 0) {
+		/* Tracer is probably gone or ENOMEM. */
 		goto error;
 	}
+	assert(ua_sess);
 
 	/*
 	 * We can iterate safely here over all UST app session sicne the create ust
@@ -2651,12 +2755,6 @@ void ust_app_global_update(struct ltt_ust_session *usess, int sock)
 				/* FIXME: Should we quit here or continue... */
 				continue;
 			}
-
-			ret = set_ust_event_filter(ua_event, app);
-			if (ret < 0) {
-				/* FIXME: Should we quit here or continue... */
-				continue;
-			}
 		}
 	}
 
@@ -2860,7 +2958,7 @@ int ust_app_validate_version(int sock)
 	app = find_app_by_sock(sock);
 	assert(app);
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	ret = ustctl_tracer_version(sock, &app->version);
 	if (ret < 0) {
@@ -2877,7 +2975,7 @@ int ust_app_validate_version(int sock)
 			UST_APP_MAJOR_VERSION);
 	app->compatible = 1;
 	rcu_read_unlock();
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return 0;
 
 error:
@@ -2886,7 +2984,7 @@ error:
 			UST_APP_MAJOR_VERSION);
 	app->compatible = 0;
 	rcu_read_unlock();
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 	return -1;
 }
 
@@ -2910,7 +3008,7 @@ int ust_app_calibrate_glb(struct lttng_ust_calibrate *calibrate)
 			continue;
 		}
 
-		health_code_update(&health_thread_cmd);
+		health_code_update();
 
 		ret = ustctl_calibrate(app->sock, calibrate);
 		if (ret < 0) {
@@ -2932,7 +3030,7 @@ int ust_app_calibrate_glb(struct lttng_ust_calibrate *calibrate)
 
 	rcu_read_unlock();
 
-	health_code_update(&health_thread_cmd);
+	health_code_update();
 
 	return ret;
 }