X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fcmd.c;h=1a3c22a6c8f87715dc85c878ec5b0c3443d7d1e3;hp=a295059fbf487ef237e97d31ffccbd9fb248fdd1;hb=9a699f7bb912d287630c8940459069a4b04d2399;hpb=0f3d405741c89373f9eb51969f5cf9fccc5ce10d

diff --git a/src/bin/lttng-sessiond/cmd.c b/src/bin/lttng-sessiond/cmd.c
index a295059fb..1a3c22a6c 100644
--- a/src/bin/lttng-sessiond/cmd.c
+++ b/src/bin/lttng-sessiond/cmd.c
@@ -907,6 +907,8 @@ error:
 
 /*
  * Connect to the relayd using URI and send the socket to the right consumer.
+ *
+ * The consumer socket lock must be held by the caller.
  */
 static int send_consumer_relayd_socket(enum lttng_domain_type domain,
 		unsigned int session_id, struct lttng_uri *relayd_uri,
@@ -920,7 +922,7 @@ static int send_consumer_relayd_socket(enum lttng_domain_type domain,
 	/* Connect to relayd and make version check if uri is the control. */
 	ret = create_connect_relayd(relayd_uri, &rsock, consumer);
 	if (ret != LTTNG_OK) {
-		goto error;
+		goto relayd_comm_error;
 	}
 	assert(rsock);
 
@@ -960,10 +962,6 @@ static int send_consumer_relayd_socket(enum lttng_domain_type domain,
 	 */
 
 close_sock:
-	(void) relayd_close(rsock);
-	free(rsock);
-
-error:
 	if (ret != LTTNG_OK) {
 		/*
 		 * The consumer output for this session should not be used anymore
@@ -972,6 +970,10 @@ error:
 		 */
 		consumer->enabled = 0;
 	}
+	(void) relayd_close(rsock);
+	free(rsock);
+
+relayd_comm_error:
 	return ret;
 }
 
@@ -979,6 +981,8 @@ error:
  * Send both relayd sockets to a specific consumer and domain.  This is a
  * helper function to facilitate sending the information to the consumer for a
  * session.
+ *
+ * The consumer socket lock must be held by the caller.
  */
 static int send_consumer_relayd_sockets(enum lttng_domain_type domain,
 		unsigned int session_id, struct consumer_output *consumer,
@@ -1650,6 +1654,16 @@ int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
 	int ret, chan_kern_created = 0, chan_ust_created = 0;
 	char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
 
+	/*
+	 * Don't try to add a context if the session has been started at
+	 * some point in time before. The tracer does not allow it and would
+	 * result in a corrupted trace.
+	 */
+	if (session->has_been_started) {
+		ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
+		goto end;
+	}
+
 	if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
 		app_ctx_provider_name = ctx->u.app_ctx.provider_name;
 		app_ctx_name = ctx->u.app_ctx.ctx_name;
@@ -3706,10 +3720,12 @@ static int set_relayd_for_snapshot(struct consumer_output *consumer,
 	rcu_read_lock();
 	cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
 			socket, node.node) {
+		pthread_mutex_lock(socket->lock);
 		ret = send_consumer_relayd_sockets(0, session->id,
 				snap_output->consumer, socket,
 				session->name, session->hostname,
 				session->live_timer);
+		pthread_mutex_unlock(socket->lock);
 		if (ret != LTTNG_OK) {
 			rcu_read_unlock();
 			goto error;