X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fsession.c;h=c3a65aafbfa6b44e327b32b165e155200afcdfbb;hb=700741dccd632e2520da055406582f39ab403795;hp=88bbe1309c4a1270cbbf418a97af3d5aeee57fb5;hpb=a7ceb342d473cc37e00d74c45b04b5378965e055;p=lttng-tools.git

diff --git a/src/bin/lttng-sessiond/session.c b/src/bin/lttng-sessiond/session.c
index 88bbe1309..c3a65aafb 100644
--- a/src/bin/lttng-sessiond/session.c
+++ b/src/bin/lttng-sessiond/session.c
@@ -1,18 +1,8 @@
 /*
- * Copyright (C)  2011 - David Goulet <david.goulet@polymtl.ca>
+ * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License, version 2 only,
- * as published by the Free Software Foundation.
+ * SPDX-License-Identifier: GPL-2.0-only
  *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
 #define _LGPL_SOURCE
@@ -802,6 +792,83 @@ end:
 	return 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.
+ */
+static
+enum lttng_error_code session_kernel_open_packets(struct ltt_session *session)
+{
+	enum lttng_error_code ret = LTTNG_OK;
+	struct consumer_socket *socket;
+	struct lttng_ht_iter iter;
+	struct cds_lfht_node *node;
+	struct ltt_kernel_channel *chan;
+
+	rcu_read_lock();
+
+	cds_lfht_first(session->kernel_session->consumer->socks->ht, &iter.iter);
+	node = cds_lfht_iter_get_node(&iter.iter);
+	socket = container_of(node, typeof(*socket), node.node);
+
+	cds_list_for_each_entry(chan,
+			&session->kernel_session->channel_list.head, list) {
+		int open_ret;
+
+		DBG("Open packet of kernel channel: channel key = %" PRIu64
+				", session name = %s, session_id = %" PRIu64,
+				chan->key, session->name, session->id);
+
+		open_ret = consumer_open_channel_packets(socket, chan->key);
+		if (open_ret < 0) {
+			/* General error (no known error expected). */
+			ret = LTTNG_ERR_UNK;
+			goto end;
+		}
+	}
+
+end:
+	rcu_read_unlock();
+	return ret;
+}
+
+enum lttng_error_code session_open_packets(struct ltt_session *session)
+{
+	enum lttng_error_code ret = LTTNG_OK;
+
+	DBG("Opening packets of session channels: session name = %s, session id = %" PRIu64,
+			session->name, session->id);
+
+	if (session->ust_session) {
+		ret = ust_app_open_packets(session);
+		if (ret != LTTNG_OK) {
+			goto end;
+		}
+	}
+
+	if (session->kernel_session) {
+		ret = session_kernel_open_packets(session);
+		if (ret != LTTNG_OK) {
+			goto end;
+		}
+	}
+
+end:
+	return ret;
+}
+
 /*
  * Set a session's current trace chunk.
  *