X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fevent.c;h=8cca21391d43dd9b20b877bc920e14d10c1a348e;hp=0fec563ad63c41c9db8e063fe98b87dbcde5b129;hb=fb27f84c28e9d8ec7c8ce5ac1b541b0671a4569e;hpb=5bcdda4ff7e938d320b497470c8c33c84e996370

diff --git a/src/bin/lttng-sessiond/event.c b/src/bin/lttng-sessiond/event.c
index 0fec563ad..8cca21391 100644
--- a/src/bin/lttng-sessiond/event.c
+++ b/src/bin/lttng-sessiond/event.c
@@ -16,6 +16,7 @@
  */
 
 #define _GNU_SOURCE
+#define _LGPL_SOURCE
 #include <errno.h>
 #include <urcu/list.h>
 #include <string.h>
@@ -27,10 +28,12 @@
 #include "channel.h"
 #include "event.h"
 #include "kernel.h"
+#include "lttng-sessiond.h"
 #include "ust-ctl.h"
 #include "ust-app.h"
 #include "trace-kernel.h"
 #include "trace-ust.h"
+#include "agent.h"
 
 /*
  * Add unique UST event based on the event name, filter bytecode and loglevel.
@@ -47,7 +50,9 @@ static void add_unique_ust_event(struct lttng_ht *ht,
 
 	key.name = event->attr.name;
 	key.filter = (struct lttng_filter_bytecode *) event->filter;
-	key.loglevel = event->attr.loglevel;
+	key.loglevel_type = event->attr.loglevel_type;
+	key.loglevel_value = event->attr.loglevel;
+	key.exclusion = event->exclusion;
 
 	node_ptr = cds_lfht_add_unique(ht->ht,
 			ht->hash_fct(event->node.key, lttng_ht_seed),
@@ -55,29 +60,19 @@ static void add_unique_ust_event(struct lttng_ht *ht,
 	assert(node_ptr == &event->node.node);
 }
 
-/*
- * Setup a lttng_event used to enable *all* syscall tracing.
- */
-static void init_syscalls_kernel_event(struct lttng_event *event)
-{
-	event->name[0] = '\0';
-	/*
-	 * We use LTTNG_EVENT* here since the trace kernel creation will make the
-	 * right changes for the kernel.
-	 */
-	event->type = LTTNG_EVENT_SYSCALL;
-}
-
 /*
  * Disable kernel tracepoint event for a channel from the kernel session.
  */
-int event_kernel_disable_tracepoint(struct ltt_kernel_session *ksession,
-		struct ltt_kernel_channel *kchan, char *event_name)
+int event_kernel_disable_event(struct ltt_kernel_channel *kchan,
+		char *event_name)
 {
 	int ret;
 	struct ltt_kernel_event *kevent;
 
-	kevent = trace_kernel_get_event_by_name(event_name, kchan);
+	assert(kchan);
+
+	kevent = trace_kernel_get_event_by_name(event_name, kchan,
+			LTTNG_EVENT_ALL);
 	if (kevent == NULL) {
 		ret = LTTNG_ERR_NO_EVENT;
 		goto error;
@@ -101,14 +96,18 @@ error:
 /*
  * Disable kernel tracepoint events for a channel from the kernel session.
  */
-int event_kernel_disable_all_tracepoints(struct ltt_kernel_session *ksession,
-		struct ltt_kernel_channel *kchan)
+int event_kernel_disable_event_type(struct ltt_kernel_channel *kchan,
+		enum lttng_event_type type)
 {
 	int ret;
 	struct ltt_kernel_event *kevent;
 
+	assert(kchan);
+
 	/* For each event in the kernel session */
 	cds_list_for_each_entry(kevent, &kchan->events_list.head, list) {
+		if (type != LTTNG_EVENT_ALL && kevent->type != type)
+			continue;
 		ret = kernel_disable_event(kevent);
 		if (ret < 0) {
 			/* We continue disabling the rest */
@@ -119,43 +118,36 @@ int event_kernel_disable_all_tracepoints(struct ltt_kernel_session *ksession,
 	return ret;
 }
 
-/*
- * Disable kernel syscall events for a channel from the kernel session.
- */
-int event_kernel_disable_all_syscalls(struct ltt_kernel_session *ksession,
-		struct ltt_kernel_channel *kchan)
-{
-	ERR("Cannot disable syscall tracing for existing session. Please destroy session instead.");
-	return LTTNG_OK;	/* Return OK so disable all succeeds */
-}
-
 /*
  * Disable all kernel event for a channel from the kernel session.
  */
-int event_kernel_disable_all(struct ltt_kernel_session *ksession,
-		struct ltt_kernel_channel *kchan)
+int event_kernel_disable_event_all(struct ltt_kernel_channel *kchan)
 {
-	int ret;
-
-	ret = event_kernel_disable_all_tracepoints(ksession, kchan);
-	if (ret != LTTNG_OK)
-		return ret;
-	ret = event_kernel_disable_all_syscalls(ksession, kchan);
-	return ret;
+	return event_kernel_disable_event_type(kchan, LTTNG_EVENT_ALL);
 }
 
 /*
  * Enable kernel tracepoint event for a channel from the kernel session.
+ * We own filter_expression and filter.
  */
-int event_kernel_enable_tracepoint(struct ltt_kernel_session *ksession,
-		struct ltt_kernel_channel *kchan, struct lttng_event *event)
+int event_kernel_enable_event(struct ltt_kernel_channel *kchan,
+		struct lttng_event *event, char *filter_expression,
+		struct lttng_filter_bytecode *filter)
 {
 	int ret;
 	struct ltt_kernel_event *kevent;
 
-	kevent = trace_kernel_get_event_by_name(event->name, kchan);
+	assert(kchan);
+	assert(event);
+
+	kevent = trace_kernel_find_event(event->name, kchan,
+			event->type, filter);
 	if (kevent == NULL) {
-		ret = kernel_create_event(event, kchan);
+		ret = kernel_create_event(event, kchan,
+			filter_expression, filter);
+		/* We have passed ownership */
+		filter_expression = NULL;
+		filter = NULL;
 		if (ret < 0) {
 			switch (-ret) {
 			case EEXIST:
@@ -184,240 +176,46 @@ int event_kernel_enable_tracepoint(struct ltt_kernel_session *ksession,
 
 	ret = LTTNG_OK;
 end:
+	free(filter_expression);
+	free(filter);
 	return ret;
 }
 
-/*
- * Enable all kernel tracepoint events of a channel of the kernel session.
- */
-int event_kernel_enable_all_tracepoints(struct ltt_kernel_session *ksession,
-		struct ltt_kernel_channel *kchan, int kernel_tracer_fd)
-{
-	int size, i, ret;
-	struct ltt_kernel_event *kevent;
-	struct lttng_event *event_list = NULL;
-
-	/* For each event in the kernel session */
-	cds_list_for_each_entry(kevent, &kchan->events_list.head, list) {
-		if (kevent->enabled == 0) {
-			ret = kernel_enable_event(kevent);
-			if (ret < 0) {
-				/* Enable failed but still continue */
-				continue;
-			}
-		}
-	}
-
-	size = kernel_list_events(kernel_tracer_fd, &event_list);
-	if (size < 0) {
-		ret = LTTNG_ERR_KERN_LIST_FAIL;
-		goto end;
-	}
-
-	for (i = 0; i < size; i++) {
-		kevent = trace_kernel_get_event_by_name(event_list[i].name, kchan);
-		if (kevent == NULL) {
-			/* Default event type for enable all */
-			event_list[i].type = LTTNG_EVENT_TRACEPOINT;
-			/* Enable each single tracepoint event */
-			ret = kernel_create_event(&event_list[i], kchan);
-			if (ret < 0) {
-				/* Ignore error here and continue */
-			}
-		}
-	}
-	free(event_list);
-
-	ret = LTTNG_OK;
-end:
-	return ret;
-
-}
-
-/*
- * Enable all kernel tracepoint events of a channel of the kernel session.
- */
-int event_kernel_enable_all_syscalls(struct ltt_kernel_session *ksession,
-		struct ltt_kernel_channel *kchan, int kernel_tracer_fd)
-{
-	int ret;
-	struct lttng_event event;
-
-	init_syscalls_kernel_event(&event);
-
-	DBG("Enabling all syscall tracing");
-
-	ret = kernel_create_event(&event, kchan);
-	if (ret < 0) {
-		if (ret == -EEXIST) {
-			ret = LTTNG_ERR_KERN_EVENT_EXIST;
-		} else {
-			ret = LTTNG_ERR_KERN_ENABLE_FAIL;
-		}
-		goto end;
-	}
-
-	ret = LTTNG_OK;
-end:
-	return ret;
-}
-
-/*
- * Enable all kernel events of a channel of the kernel session.
- */
-int event_kernel_enable_all(struct ltt_kernel_session *ksession,
-		struct ltt_kernel_channel *kchan, int kernel_tracer_fd)
-{
-	int tp_ret;
-
-	tp_ret = event_kernel_enable_all_tracepoints(ksession, kchan, kernel_tracer_fd);
-	if (tp_ret != LTTNG_OK) {
-		goto end;
-	}
-
-	/*
-	 * Reaching this code path means that all tracepoints were enabled without
-	 * errors so we ignore the error value of syscalls.
-	 *
-	 * At the moment, failing to enable syscalls on "lttng enable-event -a -k"
-	 * is not considered an error that need to be returned to the client since
-	 * tracepoints did not fail. Future work will allow us to send back
-	 * multiple errors to the client in one API call.
-	 */
-	(void) event_kernel_enable_all_syscalls(ksession, kchan, kernel_tracer_fd);
-
-end:
-	return tp_ret;
-}
-
 /*
  * ============================
  * UST : The Ultimate Frontier!
  * ============================
  */
 
-/*
- * Enable all UST tracepoints for a channel from a UST session.
- */
-int event_ust_enable_all_tracepoints(struct ltt_ust_session *usess, int domain,
-		struct ltt_ust_channel *uchan, struct lttng_filter_bytecode *filter)
-{
-	int ret, i, size;
-	struct lttng_ht_iter iter;
-	struct ltt_ust_event *uevent = NULL;
-	struct lttng_event *events = NULL;
-
-	rcu_read_lock();
-
-	switch (domain) {
-	case LTTNG_DOMAIN_UST:
-	{
-		/* Enable existing events */
-		cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent,
-				node.node) {
-			if (uevent->enabled == 0) {
-				ret = ust_app_enable_event_glb(usess, uchan, uevent);
-				if (ret < 0) {
-					continue;
-				}
-				uevent->enabled = 1;
-			}
-		}
-
-		/* Get all UST available events */
-		size = ust_app_list_events(&events);
-		if (size < 0) {
-			ret = LTTNG_ERR_UST_LIST_FAIL;
-			goto error;
-		}
-
-		for (i = 0; i < size; i++) {
-			/*
-			 * Check if event exist and if so, continue since it was enable
-			 * previously.
-			 */
-			uevent = trace_ust_find_event(uchan->events, events[i].name, filter,
-					events[i].loglevel);
-			if (uevent != NULL) {
-				ret = ust_app_enable_event_pid(usess, uchan, uevent,
-						events[i].pid);
-				if (ret < 0) {
-					if (ret != -LTTNG_UST_ERR_EXIST) {
-						ret = LTTNG_ERR_UST_ENABLE_FAIL;
-						goto error;
-					}
-				}
-				continue;
-			}
-
-			/* Create ust event */
-			uevent = trace_ust_create_event(&events[i], filter);
-			if (uevent == NULL) {
-				ret = LTTNG_ERR_FATAL;
-				goto error_destroy;
-			}
-
-			/* Create event for the specific PID */
-			ret = ust_app_enable_event_pid(usess, uchan, uevent,
-					events[i].pid);
-			if (ret < 0) {
-				if (ret == -LTTNG_UST_ERR_EXIST) {
-					ret = LTTNG_ERR_UST_EVENT_EXIST;
-					goto error;
-				} else {
-					ret = LTTNG_ERR_UST_ENABLE_FAIL;
-					goto error_destroy;
-				}
-			}
-
-			uevent->enabled = 1;
-			/* Add ltt ust event to channel */
-			rcu_read_lock();
-			add_unique_ust_event(uchan->events, uevent);
-			rcu_read_unlock();
-		}
-
-		free(events);
-		break;
-	}
-#if 0
-	case LTTNG_DOMAIN_UST_EXEC_NAME:
-	case LTTNG_DOMAIN_UST_PID:
-	case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
-#endif
-	default:
-		ret = LTTNG_ERR_UND;
-		goto error;
-	}
-
-	rcu_read_unlock();
-	return LTTNG_OK;
-
-error_destroy:
-	trace_ust_destroy_event(uevent);
-
-error:
-	free(events);
-	rcu_read_unlock();
-	return ret;
-}
-
 /*
  * Enable UST tracepoint event for a channel from a UST session.
+ * We own filter_expression, filter, and exclusion.
  */
-int event_ust_enable_tracepoint(struct ltt_ust_session *usess, int domain,
+int event_ust_enable_tracepoint(struct ltt_ust_session *usess,
 		struct ltt_ust_channel *uchan, struct lttng_event *event,
-		struct lttng_filter_bytecode *filter)
+		char *filter_expression,
+		struct lttng_filter_bytecode *filter,
+		struct lttng_event_exclusion *exclusion,
+		bool internal_event)
 {
 	int ret = LTTNG_OK, to_create = 0;
 	struct ltt_ust_event *uevent;
 
+	assert(usess);
+	assert(uchan);
+	assert(event);
+
 	rcu_read_lock();
 
 	uevent = trace_ust_find_event(uchan->events, event->name, filter,
-			event->loglevel);
-	if (uevent == NULL) {
-		uevent = trace_ust_create_event(event, filter);
+			event->loglevel_type, event->loglevel, exclusion);
+	if (!uevent) {
+		uevent = trace_ust_create_event(event, filter_expression,
+				filter, exclusion, internal_event);
+		/* We have passed ownership */
+		filter_expression = NULL;
+		filter = NULL;
+		exclusion = NULL;
 		if (uevent == NULL) {
 			ret = LTTNG_ERR_UST_ENABLE_FAIL;
 			goto error;
@@ -435,36 +233,22 @@ int event_ust_enable_tracepoint(struct ltt_ust_session *usess, int domain,
 
 	uevent->enabled = 1;
 
-	switch (domain) {
-	case LTTNG_DOMAIN_UST:
-	{
-		if (to_create) {
-			/* Create event on all UST registered apps for session */
-			ret = ust_app_create_event_glb(usess, uchan, uevent);
-		} else {
-			/* Enable event on all UST registered apps for session */
-			ret = ust_app_enable_event_glb(usess, uchan, uevent);
-		}
+	if (to_create) {
+		/* Create event on all UST registered apps for session */
+		ret = ust_app_create_event_glb(usess, uchan, uevent);
+	} else {
+		/* Enable event on all UST registered apps for session */
+		ret = ust_app_enable_event_glb(usess, uchan, uevent);
+	}
 
-		if (ret < 0) {
-			if (ret == -LTTNG_UST_ERR_EXIST) {
-				ret = LTTNG_ERR_UST_EVENT_EXIST;
-				goto end;
-			} else {
-				ret = LTTNG_ERR_UST_ENABLE_FAIL;
-				goto error;
-			}
+	if (ret < 0) {
+		if (ret == -LTTNG_UST_ERR_EXIST) {
+			ret = LTTNG_ERR_UST_EVENT_EXIST;
+			goto end;
+		} else {
+			ret = LTTNG_ERR_UST_ENABLE_FAIL;
+			goto error;
 		}
-		break;
-	}
-#if 0
-	case LTTNG_DOMAIN_UST_EXEC_NAME:
-	case LTTNG_DOMAIN_UST_PID:
-	case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
-#endif
-	default:
-		ret = LTTNG_ERR_UND;
-		goto end;
 	}
 
 	if (to_create) {
@@ -479,6 +263,9 @@ int event_ust_enable_tracepoint(struct ltt_ust_session *usess, int domain,
 
 end:
 	rcu_read_unlock();
+	free(filter_expression);
+	free(filter);
+	free(exclusion);
 	return ret;
 
 error:
@@ -494,13 +281,16 @@ error:
 		trace_ust_destroy_event(uevent);
 	}
 	rcu_read_unlock();
+	free(filter_expression);
+	free(filter);
+	free(exclusion);
 	return ret;
 }
 
 /*
  * Disable UST tracepoint of a channel from a UST session.
  */
-int event_ust_disable_tracepoint(struct ltt_ust_session *usess, int domain,
+int event_ust_disable_tracepoint(struct ltt_ust_session *usess,
 		struct ltt_ust_channel *uchan, char *event_name)
 {
 	int ret;
@@ -509,6 +299,10 @@ int event_ust_disable_tracepoint(struct ltt_ust_session *usess, int domain,
 	struct lttng_ht_iter iter;
 	struct lttng_ht *ht;
 
+	assert(usess);
+	assert(uchan);
+	assert(event_name);
+
 	ht = uchan->events;
 
 	rcu_read_lock();
@@ -532,33 +326,20 @@ int event_ust_disable_tracepoint(struct ltt_ust_session *usess, int domain,
 
 		if (uevent->enabled == 0) {
 			/* It's already disabled so everything is OK */
-			ret = LTTNG_OK;
-			continue;
+			goto next;
 		}
 
-		switch (domain) {
-		case LTTNG_DOMAIN_UST:
-			ret = ust_app_disable_event_glb(usess, uchan, uevent);
-			if (ret < 0 && ret != -LTTNG_UST_ERR_EXIST) {
-				ret = LTTNG_ERR_UST_DISABLE_FAIL;
-				goto error;
-			}
-			break;
-#if 0
-		case LTTNG_DOMAIN_UST_EXEC_NAME:
-		case LTTNG_DOMAIN_UST_PID:
-		case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
-#endif
-		default:
-			ret = LTTNG_ERR_UND;
+		ret = ust_app_disable_event_glb(usess, uchan, uevent);
+		if (ret < 0 && ret != -LTTNG_UST_ERR_EXIST) {
+			ret = LTTNG_ERR_UST_DISABLE_FAIL;
 			goto error;
 		}
-
 		uevent->enabled = 0;
 
 		DBG2("Event UST %s disabled in channel %s", uevent->attr.name,
 				uchan->name);
 
+next:
 		/* Get next duplicate event by name. */
 		cds_lfht_next_duplicate(ht->ht, trace_ust_ht_match_event_by_name,
 				event_name, &iter.iter);
@@ -573,67 +354,303 @@ error:
 }
 
 /*
- * Disable all UST tracepoints for a channel from a UST session.
+ * Enable all agent event for a given UST session.
+ *
+ * Return LTTNG_OK on success or else a LTTNG_ERR* code.
  */
-int event_ust_disable_all_tracepoints(struct ltt_ust_session *usess, int domain,
-		struct ltt_ust_channel *uchan)
+int event_agent_enable_all(struct ltt_ust_session *usess,
+		struct agent *agt, struct lttng_event *event,
+		struct lttng_filter_bytecode *filter ,char *filter_expression)
 {
-	int ret, i, size;
+	int ret;
+	struct agent_event *aevent;
 	struct lttng_ht_iter iter;
-	struct ltt_ust_event *uevent = NULL;
-	struct lttng_event *events = NULL;
 
+	assert(usess);
+
+	DBG("Event agent enabling ALL events for session %" PRIu64, usess->id);
+
+	/* Enable event on agent application through TCP socket. */
+	ret = event_agent_enable(usess, agt, event, filter, filter_expression);
+	if (ret != LTTNG_OK) {
+		goto error;
+	}
+
+	/* Flag every event that they are now enabled. */
 	rcu_read_lock();
+	cds_lfht_for_each_entry(agt->events->ht, &iter.iter, aevent,
+			node.node) {
+		aevent->enabled = 1;
+	}
+	rcu_read_unlock();
 
-	switch (domain) {
-	case LTTNG_DOMAIN_UST:
-	{
-		/* Disabling existing events */
-		cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent,
-				node.node) {
-			if (uevent->enabled == 1) {
-				ret = event_ust_disable_tracepoint(usess, domain, uchan,
-						uevent->attr.name);
-				if (ret < 0) {
-					continue;
-				}
-			}
-		}
+	ret = LTTNG_OK;
 
-		/* Get all UST available events */
-		size = ust_app_list_events(&events);
-		if (size < 0) {
-			ret = LTTNG_ERR_UST_LIST_FAIL;
+error:
+	return ret;
+}
+
+/*
+ * Enable a single agent event for a given UST session.
+ *
+ * Return LTTNG_OK on success or else a LTTNG_ERR* code.
+ */
+int event_agent_enable(struct ltt_ust_session *usess,
+		struct agent *agt, struct lttng_event *event,
+		struct lttng_filter_bytecode *filter,
+		char *filter_expression)
+{
+	int ret, created = 0;
+	struct agent_event *aevent;
+
+	assert(usess);
+	assert(event);
+	assert(agt);
+
+	DBG("Event agent enabling %s for session %" PRIu64 " with loglevel type %d "
+			", loglevel %d and filter \"%s\"", event->name,
+			usess->id, event->loglevel_type, event->loglevel,
+			filter_expression ? filter_expression : "NULL");
+
+	aevent = agent_find_event(event->name, event->loglevel_type,
+		event->loglevel, agt);
+	if (!aevent) {
+		aevent = agent_create_event(event->name, event->loglevel_type,
+				event->loglevel, filter,
+				filter_expression);
+		if (!aevent) {
+			ret = LTTNG_ERR_NOMEM;
 			goto error;
 		}
+		created = 1;
+	}
 
-		for (i = 0; i < size; i++) {
-			ret = event_ust_disable_tracepoint(usess, domain, uchan,
-					events[i].name);
-			if (ret != LTTNG_OK) {
-				/* Continue to disable the rest... */
-				continue;
-			}
-		}
+	/* Already enabled? */
+	if (aevent->enabled) {
+		goto end;
+	}
 
-		free(events);
-		break;
+	ret = agent_enable_event(aevent, agt->domain);
+	if (ret != LTTNG_OK) {
+		goto error;
+	}
+
+	/* If the event was created prior to the enable, add it to the domain. */
+	if (created) {
+		agent_add_event(aevent, agt);
+	}
+
+end:
+	return LTTNG_OK;
+
+error:
+	if (created) {
+		agent_destroy_event(aevent);
 	}
-#if 0
-	case LTTNG_DOMAIN_UST_EXEC_NAME:
-	case LTTNG_DOMAIN_UST_PID:
-	case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
-#endif
+	return ret;
+}
+
+/*
+ * Return the default event name associated with the provided UST domain. Return
+ * NULL on error.
+ */
+const char *event_get_default_agent_ust_name(enum lttng_domain_type domain)
+{
+	const char *default_event_name = NULL;
+
+	switch (domain) {
+	case LTTNG_DOMAIN_LOG4J:
+		default_event_name = DEFAULT_LOG4J_EVENT_NAME;
+		break;
+	case LTTNG_DOMAIN_JUL:
+		default_event_name = DEFAULT_JUL_EVENT_NAME;
+		break;
+	case LTTNG_DOMAIN_PYTHON:
+		default_event_name = DEFAULT_PYTHON_EVENT_NAME;
+		break;
 	default:
-		ret = LTTNG_ERR_UND;
+		assert(0);
+	}
+
+	return default_event_name;
+}
+
+/*
+ * Disable a given agent event for a given UST session.
+ *
+ * Must be called with the RCU read lock held.
+ * Return LTTNG_OK on success or else a LTTNG_ERR* code.
+ */
+static int event_agent_disable_one(struct ltt_ust_session *usess,
+		struct agent *agt, struct agent_event *aevent)
+{
+	int ret;
+	struct ltt_ust_event *uevent = NULL;
+	struct ltt_ust_channel *uchan = NULL;
+	const char *ust_event_name, *ust_channel_name;
+
+	assert(agt);
+	assert(usess);
+	assert(aevent);
+
+	DBG("Event agent disabling %s (loglevel type %d, loglevel value %d) for session %" PRIu64,
+		aevent->name, aevent->loglevel_type, aevent->loglevel_value,
+		usess->id);
+
+	/* Already disabled? */
+	if (!aevent->enabled) {
+		goto end;
+	}
+
+	if (agt->domain == LTTNG_DOMAIN_JUL) {
+		ust_channel_name = DEFAULT_JUL_CHANNEL_NAME;
+	} else if (agt->domain == LTTNG_DOMAIN_LOG4J) {
+		ust_channel_name = DEFAULT_LOG4J_CHANNEL_NAME;
+	} else if (agt->domain == LTTNG_DOMAIN_PYTHON) {
+		ust_channel_name = DEFAULT_PYTHON_CHANNEL_NAME;
+	} else {
+		ret = LTTNG_ERR_INVALID;
 		goto error;
 	}
 
-	rcu_read_unlock();
+	/*
+	 * Disable it on the UST side. First get the channel reference then find
+	 * the event and finally disable it.
+	 */
+	uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
+			(char *) ust_channel_name);
+	if (!uchan) {
+		ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
+		goto error;
+	}
+
+	ust_event_name = event_get_default_agent_ust_name(agt->domain);
+	if (!ust_event_name) {
+		ret = LTTNG_ERR_FATAL;
+		goto error;
+	}
+
+	/*
+	 * Agent UST event has its loglevel type forced to
+	 * LTTNG_UST_LOGLEVEL_ALL. The actual loglevel type/value filtering
+	 * happens thanks to an UST filter. The following -1 is actually
+	 * ignored since the type is LTTNG_UST_LOGLEVEL_ALL.
+	 */
+	uevent = trace_ust_find_event(uchan->events, (char *) ust_event_name,
+			aevent->filter, LTTNG_UST_LOGLEVEL_ALL, -1, NULL);
+	/* If the agent event exists, it must be available on the UST side. */
+	assert(uevent);
+
+	ret = ust_app_disable_event_glb(usess, uchan, uevent);
+	if (ret < 0 && ret != -LTTNG_UST_ERR_EXIST) {
+		ret = LTTNG_ERR_UST_DISABLE_FAIL;
+		goto error;
+	}
+
+	/*
+	 * Flag event that it's disabled so the shadow copy on the ust app side
+	 * will disable it if an application shows up.
+	 */
+	uevent->enabled = 0;
+
+	ret = agent_disable_event(aevent, agt->domain);
+	if (ret != LTTNG_OK) {
+		goto error;
+	}
+
+end:
 	return LTTNG_OK;
 
 error:
-	free(events);
+	return ret;
+}
+
+/*
+ * Disable all agent events matching a given name for a given UST session.
+ *
+ * Return LTTNG_OK on success or else a LTTNG_ERR* code.
+ */
+int event_agent_disable(struct ltt_ust_session *usess, struct agent *agt,
+		char *event_name)
+{
+	int ret = LTTNG_OK;
+	struct agent_event *aevent;
+	struct lttng_ht_iter iter;
+	struct lttng_ht_node_str *node;
+
+	assert(agt);
+	assert(usess);
+	assert(event_name);
+
+	DBG("Event agent disabling %s (all loglevels) for session %" PRIu64, event_name, usess->id);
+
+	rcu_read_lock();
+	agent_find_events_by_name(event_name, agt, &iter);
+	node = lttng_ht_iter_get_node_str(&iter);
+
+	if (node == NULL) {
+		DBG2("Event agent NOT found by name %s", event_name);
+		ret = LTTNG_ERR_UST_EVENT_NOT_FOUND;
+		goto end;
+	}
+
+	do {
+		aevent = caa_container_of(node, struct agent_event, node);
+		ret = event_agent_disable_one(usess, agt, aevent);
+
+		if (ret != LTTNG_OK) {
+			goto end;
+		}
+
+		/* Get next duplicate agent event by name. */
+		agent_event_next_duplicate(event_name, agt, &iter);
+		node = lttng_ht_iter_get_node_str(&iter);
+	} while (node);
+end:
 	rcu_read_unlock();
 	return ret;
 }
+/*
+ * Disable all agent event for a given UST session.
+ *
+ * Return LTTNG_OK on success or else a LTTNG_ERR* code.
+ */
+int event_agent_disable_all(struct ltt_ust_session *usess,
+		struct agent *agt)
+{
+	int ret;
+	struct agent_event *aevent;
+	struct lttng_ht_iter iter;
+
+	assert(agt);
+	assert(usess);
+
+	/*
+	 * Disable event on agent application. Continue to disable all other events
+	 * if the * event is not found.
+	 */
+	ret = event_agent_disable(usess, agt, "*");
+	if (ret != LTTNG_OK && ret != LTTNG_ERR_UST_EVENT_NOT_FOUND) {
+		goto error;
+	}
+
+	/* Disable every event. */
+	rcu_read_lock();
+	cds_lfht_for_each_entry(agt->events->ht, &iter.iter, aevent,
+			node.node) {
+		if (!aevent->enabled) {
+			continue;
+		}
+
+		ret = event_agent_disable(usess, agt, aevent->name);
+		if (ret != LTTNG_OK) {
+			goto error_unlock;
+		}
+	}
+	ret = LTTNG_OK;
+
+error_unlock:
+	rcu_read_unlock();
+error:
+	return ret;
+}