+ lttng_kvfree(filter_node);
+ }
+}
+
+void lttng_event_enabler_destroy(struct lttng_event_enabler_common *event_enabler)
+{
+ lttng_enabler_destroy(event_enabler);
+ if (event_enabler->published)
+ list_del(&event_enabler->node);
+
+ switch (event_enabler->enabler_type) {
+ case LTTNG_EVENT_ENABLER_TYPE_RECORDER:
+ {
+ struct lttng_event_recorder_enabler *event_recorder_enabler =
+ container_of(event_enabler, struct lttng_event_recorder_enabler, parent);
+
+ kfree(event_recorder_enabler);
+ break;
+ }
+ case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER:
+ {
+ struct lttng_event_notifier_enabler *event_notifier_enabler =
+ container_of(event_enabler, struct lttng_event_notifier_enabler, parent);
+
+ kfree(event_notifier_enabler);
+ break;
+ }
+ default:
+ WARN_ON_ONCE(1);
+ }
+}
+
+struct lttng_event_notifier_enabler *lttng_event_notifier_enabler_create(
+ enum lttng_enabler_format_type format_type,
+ struct lttng_kernel_abi_event_notifier *event_notifier_param,
+ struct lttng_event_notifier_group *event_notifier_group)
+{
+ struct lttng_event_notifier_enabler *event_notifier_enabler;
+
+ event_notifier_enabler = kzalloc(sizeof(*event_notifier_enabler), GFP_KERNEL);
+ if (!event_notifier_enabler)
+ return NULL;
+
+ event_notifier_enabler->parent.enabler_type = LTTNG_EVENT_ENABLER_TYPE_NOTIFIER;
+ event_notifier_enabler->parent.format_type = format_type;
+ INIT_LIST_HEAD(&event_notifier_enabler->parent.filter_bytecode_head);
+ INIT_LIST_HEAD(&event_notifier_enabler->capture_bytecode_head);
+
+ event_notifier_enabler->error_counter_index = event_notifier_param->error_counter_index;
+ event_notifier_enabler->num_captures = 0;
+
+ memcpy(&event_notifier_enabler->parent.event_param, &event_notifier_param->event,
+ sizeof(event_notifier_enabler->parent.event_param));
+
+ event_notifier_enabler->parent.enabled = 0;
+ event_notifier_enabler->parent.user_token = event_notifier_param->event.token;
+ event_notifier_enabler->group = event_notifier_group;
+ return event_notifier_enabler;
+}
+
+void lttng_event_notifier_enabler_group_add(struct lttng_event_notifier_group *event_notifier_group,
+ struct lttng_event_notifier_enabler *event_notifier_enabler)
+{
+ mutex_lock(&sessions_mutex);
+ list_add(&event_notifier_enabler->parent.node, &event_notifier_enabler->group->enablers_head);
+ event_notifier_enabler->parent.published = true;
+ lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
+ mutex_unlock(&sessions_mutex);
+}
+
+int lttng_event_notifier_enabler_enable(
+ struct lttng_event_notifier_enabler *event_notifier_enabler)
+{
+ mutex_lock(&sessions_mutex);
+ lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)->enabled = 1;
+ lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
+ mutex_unlock(&sessions_mutex);
+ return 0;
+}
+
+int lttng_event_notifier_enabler_disable(
+ struct lttng_event_notifier_enabler *event_notifier_enabler)
+{
+ mutex_lock(&sessions_mutex);
+ lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)->enabled = 0;
+ lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
+ mutex_unlock(&sessions_mutex);
+ return 0;
+}
+
+int lttng_event_notifier_enabler_attach_capture_bytecode(
+ struct lttng_event_notifier_enabler *event_notifier_enabler,
+ struct lttng_kernel_abi_capture_bytecode __user *bytecode)
+{
+ struct lttng_kernel_bytecode_node *bytecode_node;
+ struct lttng_event_enabler_common *enabler =
+ lttng_event_notifier_enabler_as_enabler(event_notifier_enabler);
+ uint32_t bytecode_len;
+ int ret;
+
+ ret = get_user(bytecode_len, &bytecode->len);
+ if (ret)
+ return ret;
+
+ bytecode_node = lttng_kvzalloc(sizeof(*bytecode_node) + bytecode_len,
+ GFP_KERNEL);
+ if (!bytecode_node)
+ return -ENOMEM;
+
+ ret = copy_from_user(&bytecode_node->bc, bytecode,
+ sizeof(*bytecode) + bytecode_len);
+ if (ret)
+ goto error_free;
+
+ bytecode_node->type = LTTNG_KERNEL_BYTECODE_TYPE_CAPTURE;
+ bytecode_node->enabler = enabler;
+
+ /* Enforce length based on allocated size */
+ bytecode_node->bc.len = bytecode_len;
+ list_add_tail(&bytecode_node->node, &event_notifier_enabler->capture_bytecode_head);
+
+ event_notifier_enabler->num_captures++;
+
+ lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
+ goto end;
+
+error_free:
+ lttng_kvfree(bytecode_node);
+end:
+ return ret;
+}
+
+static
+void lttng_event_sync_filter_state(struct lttng_kernel_event_common *event)
+{
+ int has_enablers_without_filter_bytecode = 0, nr_filters = 0;
+ struct lttng_kernel_bytecode_runtime *runtime;
+ struct lttng_enabler_ref *enabler_ref;
+
+ /* Check if has enablers without bytecode enabled */
+ list_for_each_entry(enabler_ref, &event->priv->enablers_ref_head, node) {
+ if (enabler_ref->ref->enabled
+ && list_empty(&enabler_ref->ref->filter_bytecode_head)) {
+ has_enablers_without_filter_bytecode = 1;
+ break;
+ }
+ }
+ event->priv->has_enablers_without_filter_bytecode = has_enablers_without_filter_bytecode;
+
+ /* Enable filters */
+ list_for_each_entry(runtime, &event->priv->filter_bytecode_runtime_head, node) {
+ lttng_bytecode_sync_state(runtime);
+ nr_filters++;
+ }
+ WRITE_ONCE(event->eval_filter, !(has_enablers_without_filter_bytecode || !nr_filters));
+}
+
+static
+void lttng_event_sync_capture_state(struct lttng_kernel_event_common *event)
+{
+ switch (event->type) {
+ case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
+ break;
+ case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
+ {
+ struct lttng_kernel_event_notifier *event_notifier =
+ container_of(event, struct lttng_kernel_event_notifier, parent);
+ struct lttng_kernel_bytecode_runtime *runtime;
+ int nr_captures = 0;
+
+ /* Enable captures */
+ list_for_each_entry(runtime, &event_notifier->priv->capture_bytecode_runtime_head, node) {
+ lttng_bytecode_sync_state(runtime);
+ nr_captures++;
+ }
+ WRITE_ONCE(event_notifier->eval_capture, !!nr_captures);
+ break;
+ }
+ default:
+ WARN_ON_ONCE(1);
+ }
+}
+
+static
+bool lttng_get_event_enabled_state(struct lttng_kernel_event_common *event)
+{
+ struct lttng_enabler_ref *enabler_ref;
+ bool enabled = false;
+
+ switch (event->priv->instrumentation) {
+ case LTTNG_KERNEL_ABI_TRACEPOINT:
+ lttng_fallthrough;
+ case LTTNG_KERNEL_ABI_SYSCALL:
+ /* Enable events */
+ list_for_each_entry(enabler_ref, &event->priv->enablers_ref_head, node) {
+ if (enabler_ref->ref->enabled) {
+ enabled = true;
+ break;
+ }
+ }
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ return false;
+ }
+
+ switch (event->type) {
+ case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
+ {
+ struct lttng_kernel_event_recorder *event_recorder =
+ container_of(event, struct lttng_kernel_event_recorder, parent);
+
+ /*
+ * Enabled state is based on union of enablers, with
+ * intersection of session and channel transient enable
+ * states.
+ */
+ return enabled && event_recorder->chan->parent.session->priv->tstate && event_recorder->chan->priv->parent.tstate;