Fix: snapshot should fail if no successful snapshot is taken

[lttng-tools.git] / src / bin / lttng-sessiond / cmd.c

diff --git a/src/bin/lttng-sessiond/cmd.c b/src/bin/lttng-sessiond/cmd.c
index e9fa3b462d29d533583815296d3ed20c6723ce8e..17dcfc41685a2562aa7d01f297cabe324af7354c 100644 (file)
--- a/src/bin/lttng-sessiond/cmd.c
+++ b/src/bin/lttng-sessiond/cmd.c
@@ -859,15 +859,6 @@ 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->started) {
-               ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
-               goto error;
-       }
-
        switch (domain->type) {
        case LTTNG_DOMAIN_KERNEL:
        {
@@ -876,6 +867,15 @@ 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->started) {
+                               ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
+                               goto error;
+                       }
                        ret = channel_kernel_create(session->kernel_session, attr, wpipe);
                        if (attr->name[0] != '\0') {
                                session->kernel_session->has_non_default_channel = 1;
@@ -899,6 +899,15 @@ 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->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;
@@ -1115,17 +1124,6 @@ int cmd_add_context(struct ltt_session *session, int domain,
        case LTTNG_DOMAIN_KERNEL:
                assert(session->kernel_session);
 
-               /*
-                * If a non-default channel has been created in the
-                * session, explicitely require that -c chan_name needs
-                * to be provided.
-                */
-               if (session->kernel_session->has_non_default_channel
-                               && channel_name[0] == '\0') {
-                       ret = LTTNG_ERR_NEED_CHANNEL_NAME;
-                       goto error;
-               }
-
                if (session->kernel_session->channel_count == 0) {
                        /* Create default channel */
                        ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
@@ -1147,16 +1145,6 @@ int cmd_add_context(struct ltt_session *session, int domain,
 
                assert(usess);
 
-               /*
-                * If a non-default channel has been created in the
-                * session, explicitely require that -c chan_name needs
-                * to be provided.
-                */
-               if (usess->has_non_default_channel && channel_name[0] == '\0') {
-                       ret = LTTNG_ERR_NEED_CHANNEL_NAME;
-                       goto error;
-               }
-
                chan_count = lttng_ht_get_count(usess->domain_global.channels);
                if (chan_count == 0) {
                        struct lttng_channel *attr;
@@ -2848,6 +2836,8 @@ int cmd_snapshot_record(struct ltt_session *session,
 
        if (snapshot_success) {
                session->snapshot.nb_snapshot++;
+       } else {
+               ret = LTTNG_ERR_SNAPSHOT_FAIL;
        }
 
 error: