X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fcmd.c;fp=src%2Fbin%2Flttng-sessiond%2Fcmd.c;h=5868c829f689d7015fc839ff8048197e182b5ea0;hb=19bfbd16a509837bbe57f9c00d6c2a1f0933a5a9;hp=a635c6511e3722a1356a66ccc337a760693f9c13;hpb=77ef9153bfe46228f4f5d2c02d7e89ce76d5658b;p=lttng-tools.git

diff --git a/src/bin/lttng-sessiond/cmd.c b/src/bin/lttng-sessiond/cmd.c
index a635c6511..5868c829f 100644
--- a/src/bin/lttng-sessiond/cmd.c
+++ b/src/bin/lttng-sessiond/cmd.c
@@ -1507,15 +1507,6 @@ int cmd_enable_channel(struct ltt_session *session,
 
 	rcu_read_lock();
 
-	/*
-	 * Don't try to enable a channel if the session has been started at
-	 * some point in time before. The tracer does not allow it.
-	 */
-	if (session->has_been_started) {
-		ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
-		goto error;
-	}
-
 	/*
 	 * If the session is a live session, remove the switch timer, the
 	 * live timer does the same thing but sends also synchronisation
@@ -1564,6 +1555,15 @@ int cmd_enable_channel(struct ltt_session *session,
 		kchan = trace_kernel_get_channel_by_name(attr.name,
 				session->kernel_session);
 		if (kchan == NULL) {
+			/*
+			 * Don't try to create a channel if the session has been started at
+			 * some point in time before. The tracer does not allow it.
+			 */
+			if (session->has_been_started) {
+				ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
+				goto error;
+			}
+
 			if (session->snapshot.nb_output > 0 ||
 					session->snapshot_mode) {
 				/* Enforce mmap output for snapshot sessions. */
@@ -1623,6 +1623,15 @@ int cmd_enable_channel(struct ltt_session *session,
 
 		uchan = trace_ust_find_channel_by_name(chan_ht, attr.name);
 		if (uchan == NULL) {
+			/*
+			 * Don't try to create a channel if the session has been started at
+			 * some point in time before. The tracer does not allow it.
+			 */
+			if (session->has_been_started) {
+				ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
+				goto error;
+			}
+
 			ret = channel_ust_create(usess, &attr, domain->buf_type);
 			if (attr.name[0] != '\0') {
 				usess->has_non_default_channel = 1;