health_code_update();
/*
- * Now get the channel from the consumer. This call wil populate the stream
+ * Now get the channel from the consumer. This call will populate the stream
* list of that channel and set the ust objects.
*/
if (usess->consumer->enabled) {
ret = ust_app_channel_allocate(ua_sess, uchan,
LTTNG_UST_CHAN_PER_CPU, usess,
&ua_chan);
- if (ret == 0) {
- ret = ust_app_channel_send(app, usess,
- ua_sess, ua_chan);
- } else {
- goto end;
+ if (ret < 0) {
+ goto error;
+ }
+
+ ret = ust_app_channel_send(app, usess,
+ ua_sess, ua_chan);
+ if (ret) {
+ goto error;
}
/* Add contexts. */
ret = create_ust_app_channel_context(ua_chan,
&uctx->ctx, app);
if (ret) {
- goto end;
+ goto error;
}
}
}
+
+error:
if (ret < 0) {
switch (ret) {
case -ENOTCONN:
break;
}
}
-end:
+
if (ret == 0 && _ua_chan) {
/*
* Only return the application's channel on success. Note
goto skip_setup;
}
- /*
- * Create the metadata for the application. This returns gracefully if a
- * metadata was already set for the session.
- */
- ret = create_ust_app_metadata(ua_sess, app, usess->consumer);
- if (ret < 0) {
- goto error_unlock;
- }
-
health_code_update();
skip_setup:
/*
* The caller must ensure that the application is compatible and is tracked
- * by the PID tracker.
+ * by the process attribute trackers.
*/
static
void ust_app_synchronize(struct ltt_ust_session *usess,
}
rcu_read_lock();
+
cds_lfht_for_each_entry(usess->domain_global.channels->ht, &uchan_iter,
uchan, node.node) {
struct ust_app_channel *ua_chan;
}
}
}
+
+ /*
+ * Create the metadata for the application. This returns gracefully if a
+ * metadata was already set for the session.
+ *
+ * The metadata channel must be created after the data channels as the
+ * consumer daemon assumes this ordering. When interacting with a relay
+ * daemon, the consumer will use this assumption to send the
+ * "STREAMS_SENT" message to the relay daemon.
+ */
+ ret = create_ust_app_metadata(ua_sess, app, usess->consumer);
+ if (ret < 0) {
+ goto error_unlock;
+ }
+
rcu_read_unlock();
end:
struct buffer_reg_channel *reg_chan;
struct consumer_socket *socket;
- if (!reg->registry->reg.ust->metadata_key) {
- /* Skip since no metadata is present */
- continue;
- }
-
/* Get consumer socket to use to push the metadata.*/
socket = consumer_find_socket_by_bitness(reg->bits_per_long,
usess->consumer);
}
}
+ /*
+ * The metadata channel might not be present.
+ *
+ * Consumer stream allocation can be done
+ * asynchronously and can fail on intermediary
+ * operations (i.e add context) and lead to data
+ * channels created with no metadata channel.
+ */
+ if (!reg->registry->reg.ust->metadata_key) {
+ /* Skip since no metadata is present. */
+ continue;
+ }
+
(void) push_metadata(reg->registry->reg.ust, usess->consumer);
ret = consumer_rotate_channel(socket,
rcu_read_unlock();
return cmd_ret;
}
+
+/*
+ * This function skips the metadata channel as the begin/end timestamps of a
+ * metadata packet are useless.
+ *
+ * Moreover, opening a packet after a "clear" will cause problems for live
+ * sessions as it will introduce padding that was not part of the first trace
+ * chunk. The relay daemon expects the content of the metadata stream of
+ * successive metadata trace chunks to be strict supersets of one another.
+ *
+ * For example, flushing a packet at the beginning of the metadata stream of
+ * a trace chunk resulting from a "clear" session command will cause the
+ * size of the metadata stream of the new trace chunk to not match the size of
+ * the metadata stream of the original chunk. This will confuse the relay
+ * daemon as the same "offset" in a metadata stream will no longer point
+ * to the same content.
+ */
+enum lttng_error_code ust_app_open_packets(struct ltt_session *session)
+{
+ enum lttng_error_code ret = LTTNG_OK;
+ struct lttng_ht_iter iter;
+ struct ltt_ust_session *usess = session->ust_session;
+
+ assert(usess);
+
+ rcu_read_lock();
+
+ switch (usess->buffer_type) {
+ case LTTNG_BUFFER_PER_UID:
+ {
+ struct buffer_reg_uid *reg;
+
+ cds_list_for_each_entry (
+ reg, &usess->buffer_reg_uid_list, lnode) {
+ struct buffer_reg_channel *reg_chan;
+ struct consumer_socket *socket;
+
+ socket = consumer_find_socket_by_bitness(
+ reg->bits_per_long, usess->consumer);
+ if (!socket) {
+ ret = LTTNG_ERR_FATAL;
+ goto error;
+ }
+
+ cds_lfht_for_each_entry(reg->registry->channels->ht,
+ &iter.iter, reg_chan, node.node) {
+ const int open_ret =
+ consumer_open_channel_packets(
+ socket,
+ reg_chan->consumer_key);
+
+ if (open_ret < 0) {
+ ret = LTTNG_ERR_UNK;
+ goto error;
+ }
+ }
+ }
+ break;
+ }
+ case LTTNG_BUFFER_PER_PID:
+ {
+ struct ust_app *app;
+
+ cds_lfht_for_each_entry (
+ ust_app_ht->ht, &iter.iter, app, pid_n.node) {
+ struct consumer_socket *socket;
+ struct lttng_ht_iter chan_iter;
+ struct ust_app_channel *ua_chan;
+ struct ust_app_session *ua_sess;
+ struct ust_registry_session *registry;
+
+ ua_sess = lookup_session_by_app(usess, app);
+ if (!ua_sess) {
+ /* Session not associated with this app. */
+ continue;
+ }
+
+ /* Get the right consumer socket for the application. */
+ socket = consumer_find_socket_by_bitness(
+ app->bits_per_long, usess->consumer);
+ if (!socket) {
+ ret = LTTNG_ERR_FATAL;
+ goto error;
+ }
+
+ registry = get_session_registry(ua_sess);
+ if (!registry) {
+ DBG("Application session is being torn down. Skip application.");
+ continue;
+ }
+
+ cds_lfht_for_each_entry(ua_sess->channels->ht,
+ &chan_iter.iter, ua_chan, node.node) {
+ const int open_ret =
+ consumer_open_channel_packets(
+ socket,
+ ua_chan->key);
+
+ if (open_ret < 0) {
+ /*
+ * Per-PID buffer and application going
+ * away.
+ */
+ if (open_ret == -LTTNG_ERR_CHAN_NOT_FOUND) {
+ continue;
+ }
+
+ ret = LTTNG_ERR_UNK;
+ goto error;
+ }
+ }
+ }
+ break;
+ }
+ default:
+ abort();
+ break;
+ }
+
+error:
+ rcu_read_unlock();
+ return ret;
+}
projects / lttng-tools.git / blobdiff