X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=liblttng-ust%2Flttng-events.c;h=6196fc6a59fbbd89a8336f4526e62c5060109875;hb=c0c0989ab70574e09b2f7e8b48c2da6af664a849;hp=53bb1100cab922b7fd86a0349c69ce3b057bfb98;hpb=cab88ff8cb13622233f1e0ed338d8d10a229370d;p=lttng-ust.git

diff --git a/liblttng-ust/lttng-events.c b/liblttng-ust/lttng-events.c
index 53bb1100..6196fc6a 100644
--- a/liblttng-ust/lttng-events.c
+++ b/liblttng-ust/lttng-events.c
@@ -1,23 +1,9 @@
 /*
- * lttng-events.c
- *
- * Holds LTTng per-session event registry.
+ * SPDX-License-Identifier: LGPL-2.1-only
  *
  * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; only
- * version 2.1 of the License.
- *
- * This library 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
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ * Holds LTTng per-session event registry.
  */
 
 #define _LGPL_SOURCE
@@ -1456,14 +1442,16 @@ int lttng_event_enabler_disable(struct lttng_event_enabler *event_enabler)
 
 static
 void _lttng_enabler_attach_filter_bytecode(struct lttng_enabler *enabler,
-		struct lttng_ust_bytecode_node *bytecode)
+		struct lttng_ust_bytecode_node **bytecode)
 {
-	bytecode->enabler = enabler;
-	cds_list_add_tail(&bytecode->node, &enabler->filter_bytecode_head);
+	(*bytecode)->enabler = enabler;
+	cds_list_add_tail(&(*bytecode)->node, &enabler->filter_bytecode_head);
+	/* Take ownership of bytecode */
+	*bytecode = NULL;
 }
 
 int lttng_event_enabler_attach_filter_bytecode(struct lttng_event_enabler *event_enabler,
-		struct lttng_ust_bytecode_node *bytecode)
+		struct lttng_ust_bytecode_node **bytecode)
 {
 	_lttng_enabler_attach_filter_bytecode(
 		lttng_event_enabler_as_enabler(event_enabler), bytecode);
@@ -1474,14 +1462,16 @@ int lttng_event_enabler_attach_filter_bytecode(struct lttng_event_enabler *event
 
 static
 void _lttng_enabler_attach_exclusion(struct lttng_enabler *enabler,
-		struct lttng_ust_excluder_node *excluder)
+		struct lttng_ust_excluder_node **excluder)
 {
-	excluder->enabler = enabler;
-	cds_list_add_tail(&excluder->node, &enabler->excluder_head);
+	(*excluder)->enabler = enabler;
+	cds_list_add_tail(&(*excluder)->node, &enabler->excluder_head);
+	/* Take ownership of excluder */
+	*excluder = NULL;
 }
 
 int lttng_event_enabler_attach_exclusion(struct lttng_event_enabler *event_enabler,
-		struct lttng_ust_excluder_node *excluder)
+		struct lttng_ust_excluder_node **excluder)
 {
 	_lttng_enabler_attach_exclusion(
 		lttng_event_enabler_as_enabler(event_enabler), excluder);
@@ -1510,7 +1500,7 @@ int lttng_event_notifier_enabler_disable(
 
 int lttng_event_notifier_enabler_attach_filter_bytecode(
 		struct lttng_event_notifier_enabler *event_notifier_enabler,
-		struct lttng_ust_bytecode_node *bytecode)
+		struct lttng_ust_bytecode_node **bytecode)
 {
 	_lttng_enabler_attach_filter_bytecode(
 		lttng_event_notifier_enabler_as_enabler(event_notifier_enabler),
@@ -1522,12 +1512,14 @@ int lttng_event_notifier_enabler_attach_filter_bytecode(
 
 int lttng_event_notifier_enabler_attach_capture_bytecode(
 		struct lttng_event_notifier_enabler *event_notifier_enabler,
-		struct lttng_ust_bytecode_node *bytecode)
+		struct lttng_ust_bytecode_node **bytecode)
 {
-	bytecode->enabler = lttng_event_notifier_enabler_as_enabler(
+	(*bytecode)->enabler = lttng_event_notifier_enabler_as_enabler(
 			event_notifier_enabler);
-	cds_list_add_tail(&bytecode->node,
+	cds_list_add_tail(&(*bytecode)->node,
 			&event_notifier_enabler->capture_bytecode_head);
+	/* Take ownership of bytecode */
+	*bytecode = NULL;
 	event_notifier_enabler->num_captures++;
 
 	lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
@@ -1536,7 +1528,7 @@ int lttng_event_notifier_enabler_attach_capture_bytecode(
 
 int lttng_event_notifier_enabler_attach_exclusion(
 		struct lttng_event_notifier_enabler *event_notifier_enabler,
-		struct lttng_ust_excluder_node *excluder)
+		struct lttng_ust_excluder_node **excluder)
 {
 	_lttng_enabler_attach_exclusion(
 		lttng_event_notifier_enabler_as_enabler(event_notifier_enabler),
@@ -1708,6 +1700,13 @@ void lttng_session_sync_event_enablers(struct lttng_session *session)
 	__tracepoint_probe_prune_release_queue();
 }
 
+/* Support for event notifier is introduced by probe provider major version 2. */
+static
+bool lttng_ust_probe_supports_event_notifier(struct lttng_probe_desc *probe_desc)
+{
+	return probe_desc->major >= 2;
+}
+
 static
 void lttng_create_event_notifier_if_missing(
 		struct lttng_event_notifier_enabler *event_notifier_enabler)
@@ -1759,6 +1758,18 @@ void lttng_create_event_notifier_if_missing(
 			if (found)
 				continue;
 
+			/* Check that the probe supports event notifiers, else report the error. */
+			if (!lttng_ust_probe_supports_event_notifier(probe_desc)) {
+				ERR("Probe \"%s\" contains event \"%s\" which matches an enabled event notifier, "
+					"but its version (%u.%u) is too old and does not implement event notifiers. "
+					"It needs to be recompiled against a newer version of LTTng-UST, otherwise "
+					"this event will not generate any notification.",
+					probe_desc->provider,
+					desc->name,
+					probe_desc->major,
+					probe_desc->minor);
+				continue;
+			}
 			/*
 			 * We need to create a event_notifier for this event probe.
 			 */