X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=liblttng-ust%2Flttng-events.c;h=6196fc6a59fbbd89a8336f4526e62c5060109875;hb=c0c0989ab70574e09b2f7e8b48c2da6af664a849;hp=66ec7b2ca7862715ca3295a179462266eaad4493;hpb=d37ecb3fc622dee6f80f84c21f38d32eef407262;p=lttng-ust.git

diff --git a/liblttng-ust/lttng-events.c b/liblttng-ust/lttng-events.c
index 66ec7b2c..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
@@ -34,9 +20,9 @@
 #include <time.h>
 #include <stdbool.h>
 #include <unistd.h>
+#include <dlfcn.h>
 #include <lttng/ust-endian.h>
 
-#include <urcu-bp.h>
 #include <urcu/arch.h>
 #include <urcu/compiler.h>
 #include <urcu/hlist.h>
@@ -67,6 +53,7 @@
 #include "ust-events-internal.h"
 #include "wait.h"
 #include "../libringbuffer/shm.h"
+#include "../libcounter/counter.h"
 #include "jhash.h"
 #include <lttng/ust-abi.h>
 
@@ -142,11 +129,6 @@ int lttng_loglevel_match(int loglevel,
 	}
 }
 
-void synchronize_trace(void)
-{
-	synchronize_rcu();
-}
-
 struct lttng_session *lttng_session_create(void)
 {
 	struct lttng_session *session;
@@ -171,6 +153,46 @@ struct lttng_session *lttng_session_create(void)
 	return session;
 }
 
+struct lttng_counter *lttng_ust_counter_create(
+		const char *counter_transport_name,
+		size_t number_dimensions, const struct lttng_counter_dimension *dimensions)
+{
+	struct lttng_counter_transport *counter_transport = NULL;
+	struct lttng_counter *counter = NULL;
+
+	counter_transport = lttng_counter_transport_find(counter_transport_name);
+	if (!counter_transport)
+		goto notransport;
+	counter = zmalloc(sizeof(struct lttng_counter));
+	if (!counter)
+		goto nomem;
+
+	counter->ops = &counter_transport->ops;
+	counter->transport = counter_transport;
+
+	counter->counter = counter->ops->counter_create(
+			number_dimensions, dimensions, 0,
+			-1, 0, NULL, false);
+	if (!counter->counter) {
+		goto create_error;
+	}
+
+	return counter;
+
+create_error:
+	free(counter);
+nomem:
+notransport:
+	return NULL;
+}
+
+static
+void lttng_ust_counter_destroy(struct lttng_counter *counter)
+{
+	counter->ops->counter_destroy(counter->counter);
+	free(counter);
+}
+
 struct lttng_event_notifier_group *lttng_event_notifier_group_create(void)
 {
 	struct lttng_event_notifier_group *event_notifier_group;
@@ -309,7 +331,7 @@ void lttng_session_destroy(struct lttng_session *session)
 	cds_list_for_each_entry(event, &session->events_head, node) {
 		_lttng_event_unregister(event);
 	}
-	synchronize_trace();	/* Wait for in-flight events to complete */
+	lttng_ust_synchronize_trace();	/* Wait for in-flight events to complete */
 	__tracepoint_probe_prune_release_queue();
 	cds_list_for_each_entry_safe(event_enabler, event_tmpenabler,
 			&session->enablers_head, node)
@@ -342,7 +364,7 @@ void lttng_event_notifier_group_destroy(
 			&event_notifier_group->event_notifiers_head, node)
 		_lttng_event_notifier_unregister(notifier);
 
-	synchronize_trace();
+	lttng_ust_synchronize_trace();
 
 	cds_list_for_each_entry_safe(notifier_enabler, tmpnotifier_enabler,
 			&event_notifier_group->enablers_head, node)
@@ -352,7 +374,10 @@ void lttng_event_notifier_group_destroy(
 			&event_notifier_group->event_notifiers_head, node)
 		_lttng_event_notifier_destroy(notifier);
 
-	/* Close the notification fd to the listener of event notifiers. */
+	if (event_notifier_group->error_counter)
+		lttng_ust_counter_destroy(event_notifier_group->error_counter);
+
+	/* Close the notification fd to the listener of event_notifiers. */
 
 	lttng_ust_lock_fd_tracker();
 	close_ret = close(event_notifier_group->notification_fd);
@@ -797,7 +822,7 @@ socket_error:
 
 static
 int lttng_event_notifier_create(const struct lttng_event_desc *desc,
-		uint64_t token,
+		uint64_t token, uint64_t error_counter_index,
 		struct lttng_event_notifier_group *event_notifier_group)
 {
 	struct lttng_event_notifier *event_notifier;
@@ -820,6 +845,7 @@ int lttng_event_notifier_create(const struct lttng_event_desc *desc,
 
 	event_notifier->group = event_notifier_group;
 	event_notifier->user_token = token;
+	event_notifier->error_counter_index = error_counter_index;
 
 	/* Event notifier will be enabled by enabler sync. */
 	event_notifier->enabled = 0;
@@ -829,6 +855,7 @@ int lttng_event_notifier_create(const struct lttng_event_desc *desc,
 	CDS_INIT_LIST_HEAD(&event_notifier->capture_bytecode_runtime_head);
 	CDS_INIT_LIST_HEAD(&event_notifier->enablers_ref_head);
 	event_notifier->desc = desc;
+	event_notifier->notification_send = lttng_event_notifier_notification_send;
 
 	cds_list_add(&event_notifier->node,
 			&event_notifier_group->event_notifiers_head);
@@ -1174,7 +1201,7 @@ void lttng_probe_provider_unregister_events(
 		_lttng_event_notifier_unregister);
 
 	/* Wait for grace period. */
-	synchronize_trace();
+	lttng_ust_synchronize_trace();
 	/* Prune the unregistration queue. */
 	__tracepoint_probe_prune_release_queue();
 
@@ -1373,6 +1400,7 @@ struct lttng_event_notifier_enabler *lttng_event_notifier_enabler_create(
 	CDS_INIT_LIST_HEAD(&event_notifier_enabler->base.excluder_head);
 
 	event_notifier_enabler->user_token = event_notifier_param->event.token;
+	event_notifier_enabler->error_counter_index = event_notifier_param->error_counter_index;
 	event_notifier_enabler->num_captures = 0;
 
 	memcpy(&event_notifier_enabler->base.event_param.name,
@@ -1414,14 +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);
@@ -1432,14 +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);
@@ -1468,7 +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),
@@ -1480,12 +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);
@@ -1494,7 +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),
@@ -1666,6 +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)
@@ -1717,11 +1758,24 @@ 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.
 			 */
 			ret = lttng_event_notifier_create(desc,
 				event_notifier_enabler->user_token,
+				event_notifier_enabler->error_counter_index,
 				event_notifier_group);
 			if (ret) {
 				DBG("Unable to create event_notifier %s, error %d\n",