X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fcmd.c;h=f76a4422ea644b6997b46a6ed8620f27d9ad49b2;hb=bfeab1106e53d1c5648f18a4cef0c40aa82f7714;hp=8f8278eecd0d4515eda282495918c0c279e813f2;hpb=56fa021be759b10596877bd1766e7a6cff234bfb;p=lttng-tools.git

diff --git a/src/bin/lttng-sessiond/cmd.c b/src/bin/lttng-sessiond/cmd.c
index 8f8278eec..f76a4422e 100644
--- a/src/bin/lttng-sessiond/cmd.c
+++ b/src/bin/lttng-sessiond/cmd.c
@@ -1805,7 +1805,9 @@ int cmd_start_trace(struct ltt_session *session)
 	 * possible to enable channel thus inform the client.
 	 */
 	if (usess && usess->domain_global.channels) {
+		rcu_read_lock();
 		nb_chan += lttng_ht_get_count(usess->domain_global.channels);
+		rcu_read_unlock();
 	}
 	if (ksession) {
 		nb_chan += ksession->channel_count;
@@ -2384,16 +2386,18 @@ ssize_t cmd_list_channels(int domain, struct ltt_session *session,
 		break;
 	case LTTNG_DOMAIN_UST:
 		if (session->ust_session != NULL) {
+			rcu_read_lock();
 			nb_chan = lttng_ht_get_count(
-					session->ust_session->domain_global.channels);
+				session->ust_session->domain_global.channels);
+			rcu_read_unlock();
 		}
 		DBG3("Number of UST global channels %zd", nb_chan);
-		if (nb_chan <= 0) {
+		if (nb_chan < 0) {
 			ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
+			goto error;
 		}
 		break;
 	default:
-		*channels = NULL;
 		ret = LTTNG_ERR_UND;
 		goto error;
 	}
@@ -2406,10 +2410,6 @@ ssize_t cmd_list_channels(int domain, struct ltt_session *session,
 		}
 
 		list_lttng_channels(domain, session, *channels);
-	} else {
-		*channels = NULL;
-		/* Ret value was set in the domain switch case */
-		goto error;
 	}
 
 	return nb_chan;
@@ -2695,7 +2695,7 @@ ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
 		struct lttng_snapshot_output **outputs)
 {
 	int ret, idx = 0;
-	struct lttng_snapshot_output *list;
+	struct lttng_snapshot_output *list = NULL;
 	struct lttng_ht_iter iter;
 	struct snapshot_output *output;
 
@@ -2709,7 +2709,7 @@ ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
 	 * set in no output mode.
 	 */
 	if (session->output_traces) {
-		ret = LTTNG_ERR_EPERM;
+		ret = -LTTNG_ERR_EPERM;
 		goto error;
 	}
 
@@ -2720,11 +2720,12 @@ ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
 
 	list = zmalloc(session->snapshot.nb_output * sizeof(*list));
 	if (!list) {
-		ret = LTTNG_ERR_NOMEM;
+		ret = -LTTNG_ERR_NOMEM;
 		goto error;
 	}
 
 	/* Copy list from session to the new list object. */
+	rcu_read_lock();
 	cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
 			output, node.node) {
 		assert(output->consumer);
@@ -2739,28 +2740,28 @@ ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
 			ret = uri_to_str_url(&output->consumer->dst.net.control,
 					list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
 			if (ret < 0) {
-				ret = LTTNG_ERR_NOMEM;
-				goto free_error;
+				ret = -LTTNG_ERR_NOMEM;
+				goto error;
 			}
 
 			/* Data URI. */
 			ret = uri_to_str_url(&output->consumer->dst.net.data,
 					list[idx].data_url, sizeof(list[idx].data_url));
 			if (ret < 0) {
-				ret = LTTNG_ERR_NOMEM;
-				goto free_error;
+				ret = -LTTNG_ERR_NOMEM;
+				goto error;
 			}
 		}
 		idx++;
 	}
 
 	*outputs = list;
-	return session->snapshot.nb_output;
-
-free_error:
-	free(list);
+	list = NULL;
+	ret = session->snapshot.nb_output;
 error:
-	return -ret;
+	free(list);
+	rcu_read_unlock();
+	return ret;
 }
 
 /*