rcu_read_lock();
session = session_find_by_id(ua_chan->session->tracing_id);
- if (!session) {
- ERR("Missing LTT session to get discarded events");
- goto end;
- }
- if (!session->ust_session) {
- ERR("Missing UST session to get discarded events");
+ if (!session || !session->ust_session) {
+ /*
+ * Not finding the session is not an error because there are
+ * multiple ways the channels can be torn down.
+ *
+ * 1) The session daemon can initiate the destruction of the
+ * ust app session after receiving a destroy command or
+ * during its shutdown/teardown.
+ * 2) The application, since we are in per-pid tracing, is
+ * unregistering and tearing down its ust app session.
+ *
+ * Both paths are protected by the session list lock which
+ * ensures that the accounting of lost packets and discarded
+ * events is done exactly once. The session is then unpublished
+ * from the session list, resulting in this condition.
+ */
goto end;
}
char *metadata_str = NULL;
size_t len, offset, new_metadata_len_sent;
ssize_t ret_val;
- uint64_t metadata_key;
+ uint64_t metadata_key, metadata_version;
assert(registry);
assert(socket);
offset = registry->metadata_len_sent;
len = registry->metadata_len - registry->metadata_len_sent;
new_metadata_len_sent = registry->metadata_len;
+ metadata_version = registry->metadata_version;
if (len == 0) {
DBG3("No metadata to push for metadata key %" PRIu64,
registry->metadata_key);
* different bidirectionnal communication sockets.
*/
ret = consumer_push_metadata(socket, metadata_key,
- metadata_str, len, offset);
+ metadata_str, len, offset, metadata_version);
pthread_mutex_lock(®istry->lock);
if (ret < 0) {
/*
if (overwrite) {
ret = consumer_get_lost_packets(ust_session_id,
consumer_chan_key, consumer, lost);
+ *discarded = 0;
} else {
ret = consumer_get_discarded_events(ust_session_id,
consumer_chan_key, consumer, discarded);
+ *lost = 0;
}
end:
if (overwrite) {
ret = consumer_get_lost_packets(usess->id, ua_chan->key,
consumer, lost);
+ *discarded = 0;
goto end;
} else {
ret = consumer_get_discarded_events(usess->id,
ua_chan->key, consumer, discarded);
+ *lost = 0;
goto end;
}
}