X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;ds=sidebyside;f=src%2Fcommon%2Fconsumer.c;h=c1dadddb3dd08854bffd8eef8cca3e9a76e82bed;hb=3f8e211fbe73cbcf69d52af5e839b14d1a951ed7;hp=761ce93753667f1b93d6f151c93a68d014855e7f;hpb=6197aea7399cfe3bb67f8602ba4c3122867ecf52;p=lttng-tools.git

diff --git a/src/common/consumer.c b/src/common/consumer.c
index 761ce9375..c1dadddb3 100644
--- a/src/common/consumer.c
+++ b/src/common/consumer.c
@@ -274,12 +274,19 @@ void consumer_del_stream(struct lttng_consumer_stream *stream)
 		uatomic_dec(&relayd->refcount);
 		assert(uatomic_read(&relayd->refcount) >= 0);
 
+		/* Closing streams requires to lock the control socket. */
+		pthread_mutex_lock(&relayd->ctrl_sock_mutex);
 		ret = relayd_send_close_stream(&relayd->control_sock,
 				stream->relayd_stream_id,
 				stream->next_net_seq_num - 1);
+		pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
 		if (ret < 0) {
-			ERR("Unable to close stream on the relayd. Continuing");
-			/* Continue here. There is nothing we can do for the relayd.*/
+			DBG("Unable to close stream on the relayd. Continuing");
+			/*
+			 * Continue here. There is nothing we can do for the relayd.
+			 * Chances are that the relayd has closed the socket so we just
+			 * continue cleaning up.
+			 */
 		}
 
 		/* Both conditions are met, we destroy the relayd. */
@@ -434,8 +441,10 @@ end:
 }
 
 /*
- * Add relayd socket to global consumer data hashtable.
+ * Add relayd socket to global consumer data hashtable. RCU read side lock MUST
+ * be acquired before calling this.
  */
+
 int consumer_add_relayd(struct consumer_relayd_sock_pair *relayd)
 {
 	int ret = 0;
@@ -447,20 +456,15 @@ int consumer_add_relayd(struct consumer_relayd_sock_pair *relayd)
 		goto end;
 	}
 
-	rcu_read_lock();
-
 	lttng_ht_lookup(consumer_data.relayd_ht,
 			(void *)((unsigned long) relayd->net_seq_idx), &iter);
 	node = lttng_ht_iter_get_node_ulong(&iter);
 	if (node != NULL) {
-		rcu_read_unlock();
 		/* Relayd already exist. Ignore the insertion */
 		goto end;
 	}
 	lttng_ht_add_unique_ulong(consumer_data.relayd_ht, &relayd->node);
 
-	rcu_read_unlock();
-
 end:
 	return ret;
 }
@@ -1095,7 +1099,11 @@ end:
 }
 
 /*
- * Mmap the ring buffer, read it and write the data to the tracefile.
+ * Mmap the ring buffer, read it and write the data to the tracefile. This is a
+ * core function for writing trace buffers to either the local filesystem or
+ * the network.
+ *
+ * Careful review MUST be put if any changes occur!
  *
  * Returns the number of bytes written
  */
@@ -1168,12 +1176,6 @@ ssize_t lttng_consumer_on_read_subbuffer_mmap(
 					written = ret;
 					goto end;
 				}
-
-				/*
-				 * We do this so the return value can match the len passed as
-				 * argument to this function.
-				 */
-				written -= sizeof(stream->relayd_stream_id);
 			}
 		}
 		/* Else, use the default set before which is the filesystem. */