X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=lttng-sessiond%2Fust-app.c;h=35688702602eb4fd5d91b9825da95dc4acaf81fd;hp=a30b01dca37ce7515d183430921e79929d66c391;hb=84cd17c63cde7ea5d7a0ad037dd41e8297658812;hpb=ba767faf163cac5db9de0c36051928f3843ff3f9

diff --git a/lttng-sessiond/ust-app.c b/lttng-sessiond/ust-app.c
index a30b01dca..356887026 100644
--- a/lttng-sessiond/ust-app.c
+++ b/lttng-sessiond/ust-app.c
@@ -47,6 +47,7 @@ static void delete_ust_app_event(int sock, struct ust_app_event *ua_event)
 	//}
 
 	ustctl_release_object(sock, ua_event->obj);
+	free(ua_event->obj);
 	free(ua_event);
 }
 
@@ -56,11 +57,9 @@ static void delete_ust_app_event(int sock, struct ust_app_event *ua_event)
  */
 static void delete_ust_app_stream(int sock, struct ltt_ust_stream *stream)
 {
-	//TODO
-	//stream is used for passing to consumer.
-	//send_channel_streams is responsible for freeing the streams.
-	//note that this will not play well with flight recorder mode:
-	//we might need a criterion to discard the streams.
+	ustctl_release_object(sock, stream->obj);
+	free(stream->obj);
+	free(stream);
 }
 
 /*
@@ -75,6 +74,7 @@ static void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan)
 	struct ltt_ust_stream *stream, *stmp;
 
 	cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
+		cds_list_del(&stream->list);
 		delete_ust_app_stream(sock, stream);
 	}
 
@@ -95,6 +95,9 @@ static void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan)
 		ERR("UST app destroy session hashtable failed");
 		goto error;
 	}
+	ustctl_release_object(sock, ua_chan->obj);
+	free(ua_chan->obj);
+	free(ua_chan);
 
 error:
 	return;
@@ -112,10 +115,10 @@ static void delete_ust_app_session(int sock,
 	struct ust_app_channel *ua_chan;
 
 	if (ua_sess->metadata) {
-		/*
-		 * We do NOT release the stream object and metadata object since they
-		 * are release when fds are sent to the consumer.
-		 */
+		ustctl_release_object(sock, ua_sess->metadata->stream_obj);
+		free(ua_sess->metadata->stream_obj);
+		ustctl_release_object(sock, ua_sess->metadata->obj);
+		free(ua_sess->metadata->obj);
 	}
 
 	cds_lfht_for_each_entry(ua_sess->channels, &iter, ua_chan, node) {
@@ -143,6 +146,7 @@ static void delete_ust_app(struct ust_app *app)
 	struct cds_lfht_node *node;
 	struct cds_lfht_iter iter;
 	struct ust_app_session *ua_sess;
+	int sock;
 
 	rcu_read_lock();
 
@@ -167,9 +171,8 @@ static void delete_ust_app(struct ust_app *app)
 	/* Socket is already closed at this point */
 
 	/* Delete ust app sessions info */
-	if (app->sock_closed) {
-		app->key.sock = -1;
-	}
+	sock = app->key.sock;
+	app->key.sock = -1;
 
 	cds_lfht_for_each_entry(app->sessions, &iter, ua_sess, node) {
 		hashtable_del(app->sessions, &iter);
@@ -182,9 +185,13 @@ static void delete_ust_app(struct ust_app *app)
 		goto end;
 	}
 
-	if (!app->sock_closed) {
-		close(app->key.sock);
-	}
+	/*
+	 * Wait until we have removed the key from the sock hash table
+	 * before closing this socket, otherwise an application could
+	 * re-use the socket ID and race with the teardown, using the
+	 * same hash table entry.
+	 */
+	close(sock);
 
 	DBG2("UST app pid %d deleted", app->key.pid);
 	free(app);
@@ -503,17 +510,37 @@ static void shadow_copy_channel(struct ust_app_channel *ua_chan,
  * Copy data between a UST app session and a regular LTT session.
  */
 static void shadow_copy_session(struct ust_app_session *ua_sess,
-		struct ltt_ust_session *usess)
+		struct ltt_ust_session *usess,
+		struct ust_app *app)
 {
 	struct cds_lfht_node *ua_chan_node;
 	struct cds_lfht_iter iter;
 	struct ltt_ust_channel *uchan;
 	struct ust_app_channel *ua_chan;
+	time_t rawtime;
+	struct tm *timeinfo;
+	char datetime[16];
+	int ret;
+
+	/* Get date and time for unique app path */
+	time(&rawtime);
+	timeinfo = localtime(&rawtime);
+	strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
 
 	DBG2("Shadow copy of session handle %d", ua_sess->handle);
 
 	ua_sess->uid = usess->uid;
 
+	ret = snprintf(ua_sess->path, PATH_MAX,
+			"%s/%s-%d-%s",
+			usess->pathname, app->name, app->key.pid,
+			datetime);
+	if (ret < 0) {
+		PERROR("asprintf UST shadow copy session");
+		/* TODO: We cannot return an error from here.. */
+		assert(0);
+	}
+
 	/* TODO: support all UST domain */
 
 	/* Iterate over all channels in global domain. */
@@ -541,6 +568,16 @@ static void shadow_copy_session(struct ust_app_session *ua_sess,
 	}
 }
 
+static
+void __lookup_session_by_app(struct ltt_ust_session *usess,
+			struct ust_app *app, struct cds_lfht_iter *iter)
+{
+	/* Get right UST app session from app */
+	(void) hashtable_lookup(app->sessions,
+			(void *) ((unsigned long) usess->uid), sizeof(void *),
+			iter);
+}
+
 /*
  * Return ust app session from the app session hashtable using the UST session
  * uid.
@@ -551,9 +588,8 @@ static struct ust_app_session *lookup_session_by_app(
 	struct cds_lfht_iter iter;
 	struct cds_lfht_node *node;
 
-	/* Get right UST app session from app */
-	node = hashtable_lookup(app->sessions,
-			(void *) ((unsigned long) usess->uid), sizeof(void *), &iter);
+	__lookup_session_by_app(usess, app, &iter);
+	node = hashtable_iter_get_node(&iter);
 	if (node == NULL) {
 		goto error;
 	}
@@ -585,7 +621,7 @@ static struct ust_app_session *create_ust_app_session(
 			/* Only malloc can failed so something is really wrong */
 			goto error;
 		}
-		shadow_copy_session(ua_sess, usess);
+		shadow_copy_session(ua_sess, usess, app);
 	}
 
 	if (ua_sess->handle == -1) {
@@ -727,21 +763,14 @@ static int create_ust_app_metadata(struct ust_app_session *ua_sess,
 			goto error;
 		}
 
-		ret = snprintf(ua_sess->metadata->pathname, PATH_MAX, "%s/%s-%d",
-				pathname, app->name, app->key.pid);
-		if (ret < 0) {
-			PERROR("asprintf UST create stream");
-			goto error;
-		}
-
-		ret = mkdir(ua_sess->metadata->pathname, S_IRWXU | S_IRWXG);
+		ret = mkdir(ua_sess->path, S_IRWXU | S_IRWXG);
 		if (ret < 0) {
 			PERROR("mkdir UST metadata");
 			goto error;
 		}
 
-		ret = snprintf(ua_sess->metadata->pathname, PATH_MAX, "%s/%s-%d/metadata",
-				pathname, app->name, app->key.pid);
+		ret = snprintf(ua_sess->metadata->pathname, PATH_MAX,
+				"%s/metadata", ua_sess->path);
 		if (ret < 0) {
 			PERROR("asprintf UST create stream");
 			goto error;
@@ -868,10 +897,6 @@ void ust_app_unregister(int sock)
 		goto error;
 	}
 
-	/* We got called because the socket was closed on the remote end. */
-	close(sock);
-	/* Using a flag because we still need "sock" as a key. */
-	lta->sock_closed = 1;
 	hashtable_del(ust_app_ht, &iter);
 	call_rcu(&node->head, delete_ust_app_rcu);
 error:
@@ -970,8 +995,6 @@ void ust_app_clean_list(void)
 
 	cds_lfht_for_each(ust_app_ht, &iter, node) {
 		app = caa_container_of(node, struct ust_app, node);
-		close(app->key.sock);
-		app->sock_closed = 1;
 
 		ret = hashtable_del(ust_app_ht, &iter);
 		if (!ret) {
@@ -1111,6 +1134,10 @@ int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
 		goto error_rcu_unlock;
 	}
 
+	/* upon restart, we skip the setup, already done */
+	if (ua_sess->started)
+		goto skip_setup;
+
 	ret = create_ust_app_metadata(ua_sess, usess->pathname, app);
 	if (ret < 0) {
 		goto error_rcu_unlock;
@@ -1137,9 +1164,9 @@ int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
 
 			/* Order is important */
 			cds_list_add_tail(&ustream->list, &ua_chan->streams.head);
-			ret = snprintf(ustream->pathname, PATH_MAX, "%s/%s-%d/%s_%u",
-					usess->pathname, app->name, app->key.pid,
-					ua_chan->name, ua_chan->streams.count++);
+			ret = snprintf(ustream->pathname, PATH_MAX, "%s/%s_%u",
+					ua_sess->path, ua_chan->name,
+					ua_chan->streams.count++);
 			if (ret < 0) {
 				PERROR("asprintf UST create stream");
 				continue;
@@ -1154,7 +1181,9 @@ int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
 	if (ret < 0) {
 		goto error_rcu_unlock;
 	}
+	ua_sess->started = 1;
 
+skip_setup:
 	/* This start the UST tracing */
 	ret = ustctl_start_session(app->key.sock, ua_sess->handle);
 	if (ret < 0) {
@@ -1174,6 +1203,100 @@ error_rcu_unlock:
 	return -1;
 }
 
+/*
+ * Stop tracing for a specific UST session and app.
+ */
+int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app)
+{
+	int ret = 0;
+	struct ust_app_session *ua_sess;
+
+	DBG("Stopping tracing for ust app pid %d", app->key.pid);
+
+	rcu_read_lock();
+
+	ua_sess = lookup_session_by_app(usess, app);
+	if (ua_sess == NULL) {
+		/* Only malloc can failed so something is really wrong */
+		goto error_rcu_unlock;
+	}
+
+#if 0	/* only useful when periodical flush will be supported */
+	/* need to keep a handle on shm in session for this. */
+	/* Flush all buffers before stopping */
+	ret = ustctl_flush_buffer(usess->sock, usess->metadata->obj);
+	if (ret < 0) {
+		ERR("UST metadata flush failed");
+	}
+
+	cds_list_for_each_entry(ustchan, &usess->channels.head, list) {
+		ret = ustctl_flush_buffer(usess->sock, ustchan->obj);
+		if (ret < 0) {
+			ERR("UST flush buffer error");
+		}
+	}
+#endif
+
+	/* This inhibits UST tracing */
+	ret = ustctl_stop_session(app->key.sock, ua_sess->handle);
+	if (ret < 0) {
+		ERR("Error stopping tracing for app pid: %d", app->key.pid);
+		goto error_rcu_unlock;
+	}
+
+	rcu_read_unlock();
+
+	/* Quiescent wait after stopping trace */
+	ustctl_wait_quiescent(app->key.sock);
+
+	return 0;
+
+error_rcu_unlock:
+	rcu_read_unlock();
+	return -1;
+}
+
+/*
+ * Destroy a specific UST session in apps.
+ */
+int ust_app_destroy_trace(struct ltt_ust_session *usess, struct ust_app *app)
+{
+	struct ust_app_session *ua_sess;
+	struct lttng_ust_object_data obj;
+	struct cds_lfht_iter iter;
+	struct cds_lfht_node *node;
+
+	DBG("Destroy tracing for ust app pid %d", app->key.pid);
+
+	rcu_read_lock();
+
+	__lookup_session_by_app(usess, app, &iter);
+	node = hashtable_iter_get_node(&iter);
+	if (node == NULL) {
+		/* Only malloc can failed so something is really wrong */
+		goto error_rcu_unlock;
+	}
+	ua_sess = caa_container_of(node, struct ust_app_session, node);
+	hashtable_del(app->sessions, &iter);
+	delete_ust_app_session(app->key.sock, ua_sess);
+	obj.handle = ua_sess->handle;
+	obj.shm_fd = -1;
+	obj.wait_fd = -1;
+	obj.memory_map_size = 0;
+	ustctl_release_object(app->key.sock, &obj);
+
+	rcu_read_unlock();
+
+	/* Quiescent wait after stopping trace */
+	ustctl_wait_quiescent(app->key.sock);
+
+	return 0;
+
+error_rcu_unlock:
+	rcu_read_unlock();
+	return -1;
+}
+
 /*
  * Start tracing for the UST session.
  */
@@ -1200,6 +1323,58 @@ int ust_app_start_trace_all(struct ltt_ust_session *usess)
 	return 0;
 }
 
+/*
+ * Start tracing for the UST session.
+ */
+int ust_app_stop_trace_all(struct ltt_ust_session *usess)
+{
+	int ret = 0;
+	struct cds_lfht_iter iter;
+	struct ust_app *app;
+
+	DBG("Stopping all UST traces");
+
+	rcu_read_lock();
+
+	cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
+		ret = ust_app_stop_trace(usess, app);
+		if (ret < 0) {
+			/* Continue to next apps even on error */
+			continue;
+		}
+	}
+
+	rcu_read_unlock();
+
+	return 0;
+}
+
+/*
+ * Destroy app UST session.
+ */
+int ust_app_destroy_trace_all(struct ltt_ust_session *usess)
+{
+	int ret = 0;
+	struct cds_lfht_iter iter;
+	struct ust_app *app;
+
+	DBG("Destroy all UST traces");
+
+	rcu_read_lock();
+
+	cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
+		ret = ust_app_destroy_trace(usess, app);
+		if (ret < 0) {
+			/* Continue to next apps even on error */
+			continue;
+		}
+	}
+
+	rcu_read_unlock();
+
+	return 0;
+}
+
 /*
  * Add channels/events from UST global domain to registered apps at sock.
  */