X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fnotification-thread-events.c;h=747902612d93059705cd9d987cde39e1cc757a31;hp=a878c0dbef96b57c3555672b1324d2b9ae6bd9fe;hb=a17b133bc868e046f285146e26a5bbe2a569b892;hpb=6900ae815e88b89e381a9c20021c5adbca46e468 diff --git a/src/bin/lttng-sessiond/notification-thread-events.c b/src/bin/lttng-sessiond/notification-thread-events.c index a878c0dbe..747902612 100644 --- a/src/bin/lttng-sessiond/notification-thread-events.c +++ b/src/bin/lttng-sessiond/notification-thread-events.c @@ -125,19 +125,6 @@ struct lttng_condition_list_element { struct cds_list_head node; }; -/* - * Facilities to carry the different notifications type in the action processing - * code path. - */ -struct lttng_event_notifier_notification { - union { - struct lttng_ust_event_notifier_notification *ust; - struct lttng_kernel_event_notifier_notification *kernel; - } notification; - uint64_t token; - enum lttng_domain_type type; -}; - struct channel_state_sample { struct channel_key key; struct cds_lfht_node channel_state_ht_node; @@ -206,6 +193,11 @@ int client_handle_transmission_status( enum client_transmission_status transmission_status, struct notification_thread_state *state); +static +int handle_one_event_notifier_notification( + struct notification_thread_state *state, + int pipe, enum lttng_domain_type domain); + static void free_lttng_trigger_ht_element_rcu(struct rcu_head *node); @@ -1654,7 +1646,7 @@ int handle_notification_thread_command_add_channel( DBG("[notification-thread] Adding channel %s from session %s, channel key = %" PRIu64 " in %s domain", channel_name, session_name, channel_key_int, - channel_domain == LTTNG_DOMAIN_KERNEL ? "kernel" : "user space"); + lttng_domain_type_str(channel_domain)); CDS_INIT_LIST_HEAD(&trigger_list); @@ -1755,7 +1747,7 @@ int handle_notification_thread_command_remove_channel( struct channel_info *channel_info; DBG("[notification-thread] Removing channel key = %" PRIu64 " in %s domain", - channel_key, domain == LTTNG_DOMAIN_KERNEL ? "kernel" : "user space"); + channel_key, lttng_domain_type_str(domain)); rcu_read_lock(); @@ -1993,6 +1985,59 @@ end: return ret; } +static +int drain_event_notifier_notification_pipe( + struct notification_thread_state *state, + int pipe, enum lttng_domain_type domain) +{ + struct lttng_poll_event events = {0}; + int ret; + + ret = lttng_poll_create(&events, 1, LTTNG_CLOEXEC); + if (ret < 0) { + ERR("[notification-thread] Error creating lttng_poll_event"); + goto end; + } + + ret = lttng_poll_add(&events, pipe, LPOLLIN); + if (ret < 0) { + ERR("[notification-thread] Error adding fd event notifier notification pipe to lttng_poll_event: fd = %d", + pipe); + goto end; + } + + while (true) { + /* + * Continue to consume notifications as long as there are new + * ones coming in. The tracer has been asked to stop producing + * them. + * + * LPOLLIN is explicitly checked since LPOLLHUP is implicitly + * monitored (on Linux, at least) and will be returned when + * the pipe is closed but empty. + */ + ret = lttng_poll_wait_interruptible(&events, 0); + if (ret == 0 || (LTTNG_POLL_GETEV(&events, 0) & LPOLLIN) == 0) { + /* No more notification to be read on this pipe. */ + ret = 0; + goto end; + } else if (ret < 0) { + PERROR("Failed on lttng_poll_wait_interruptible() call"); + ret = -1; + goto end; + } + + ret = handle_one_event_notifier_notification(state, pipe, domain); + if (ret) { + ERR("[notification-thread] Error consuming an event notifier notification from pipe: fd = %d", + pipe); + } + } +end: + lttng_poll_clean(&events); + return ret; +} + static int handle_notification_thread_command_remove_tracer_event_source( struct notification_thread_state *state, @@ -2049,6 +2094,24 @@ int handle_notification_thread_command_remove_tracer_event_source( source_element->is_fd_in_poll_set = false; + ret = drain_event_notifier_notification_pipe(state, tracer_event_source_fd, + source_element->domain); + if (ret) { + ERR("[notification-thread] Error draining event notifier notification: tracer_event_source_fd = %d, domain = %s", + tracer_event_source_fd, + lttng_domain_type_str(source_element->domain)); + cmd_result = LTTNG_ERR_FATAL; + goto end; + } + + /* + * The drain_event_notifier_notification_pipe() call might have read + * data from an fd that we received in event in the latest _poll_wait() + * call. Make sure the thread call poll_wait() again to ensure we have + * a clean state. + */ + state->restart_poll = true; + end: free(source_element); *_cmd_result = cmd_result; @@ -2610,11 +2673,15 @@ int handle_notification_thread_command_register_trigger( ret = evaluate_session_condition_for_client(condition, state, &evaluation, &object_uid, &object_gid); + LTTNG_OPTIONAL_SET(&object_creds.uid, object_uid); + LTTNG_OPTIONAL_SET(&object_creds.gid, object_gid); break; case LTTNG_OBJECT_TYPE_CHANNEL: ret = evaluate_channel_condition_for_client(condition, state, &evaluation, &object_uid, &object_gid); + LTTNG_OPTIONAL_SET(&object_creds.uid, object_uid); + LTTNG_OPTIONAL_SET(&object_creds.gid, object_gid); break; case LTTNG_OBJECT_TYPE_NONE: ret = 0; @@ -2630,9 +2697,6 @@ int handle_notification_thread_command_register_trigger( goto error_put_client_list; } - LTTNG_OPTIONAL_SET(&object_creds.uid, object_uid); - LTTNG_OPTIONAL_SET(&object_creds.gid, object_gid); - DBG("Newly registered trigger's condition evaluated to %s", evaluation ? "true" : "false"); if (!evaluation) { @@ -4173,34 +4237,28 @@ end: return ret; } -int handle_notification_thread_event_notification(struct notification_thread_state *state, - int notification_pipe_read_fd, - enum lttng_domain_type domain) +static +struct lttng_event_notifier_notification *recv_one_event_notifier_notification( + int notification_pipe_read_fd, enum lttng_domain_type domain) { int ret; - struct lttng_ust_event_notifier_notification ust_notification; - struct lttng_kernel_event_notifier_notification kernel_notification; - struct cds_lfht_node *node; - struct cds_lfht_iter iter; - struct notification_trigger_tokens_ht_element *element; - enum lttng_action_type action_type; - const struct lttng_action *action; - struct lttng_event_notifier_notification notification; + uint64_t token; + struct lttng_event_notifier_notification *notification = NULL; void *reception_buffer; size_t reception_size; - notification.type = domain; + struct lttng_ust_event_notifier_notification ust_notification; + struct lttng_kernel_event_notifier_notification kernel_notification; + /* Init lttng_event_notifier_notification */ switch(domain) { case LTTNG_DOMAIN_UST: reception_buffer = (void *) &ust_notification; reception_size = sizeof(ust_notification); - notification.notification.ust = &ust_notification; break; case LTTNG_DOMAIN_KERNEL: reception_buffer = (void *) &kernel_notification; reception_size = sizeof(kernel_notification); - notification.notification.kernel = &kernel_notification; break; default: abort(); @@ -4221,26 +4279,47 @@ int handle_notification_thread_event_notification(struct notification_thread_sta switch(domain) { case LTTNG_DOMAIN_UST: - notification.token = ust_notification.token; + token = ust_notification.token; break; case LTTNG_DOMAIN_KERNEL: - notification.token = kernel_notification.token; + token = kernel_notification.token; break; default: abort(); } + notification = lttng_event_notifier_notification_create( + token, domain); +end: + return notification; +} + +static +int dispatch_one_event_notifier_notification(struct notification_thread_state *state, + struct lttng_event_notifier_notification *notification) +{ + struct cds_lfht_node *node; + struct cds_lfht_iter iter; + struct notification_trigger_tokens_ht_element *element; + enum lttng_trigger_status trigger_status; + struct lttng_evaluation *evaluation = NULL; + enum action_executor_status executor_status; + struct notification_client_list *client_list = NULL; + const char *trigger_name; + int ret; + /* Find triggers associated with this token. */ rcu_read_lock(); cds_lfht_lookup(state->trigger_tokens_ht, - hash_key_u64(¬ification.token, lttng_ht_seed), - match_trigger_token, ¬ification.token, &iter); + hash_key_u64(¬ification->tracer_token, lttng_ht_seed), + match_trigger_token, ¬ification->tracer_token, &iter); node = cds_lfht_iter_get_node(&iter); - if (caa_likely(!node)) { + if (caa_unlikely(!node)) { /* - * This is not an error, slow consumption of the pipe can lead - * to situations where a trigger is removed but we still get - * tracer notification matching to a previous trigger. + * This is not an error, slow consumption of the tracer + * notifications can lead to situations where a trigger is + * removed but we still get tracer notifications matching a + * trigger that no longer exists. */ ret = 0; goto end_unlock; @@ -4250,22 +4329,131 @@ int handle_notification_thread_event_notification(struct notification_thread_sta struct notification_trigger_tokens_ht_element, node); - action = lttng_trigger_get_const_action(element->trigger); - action_type = lttng_action_get_type(action); - DBG("Received message from tracer event source: event source fd = %d, token = %" PRIu64 ", action type = '%s'", - notification_pipe_read_fd, notification.token, - lttng_action_type_string(action_type)); + if (!lttng_trigger_should_fire(element->trigger)) { + ret = 0; + goto end_unlock; + } - /* TODO: Perform actions */ + lttng_trigger_fire(element->trigger); - ret = 0; + trigger_status = lttng_trigger_get_name(element->trigger, &trigger_name); + assert(trigger_status == LTTNG_TRIGGER_STATUS_OK); + + evaluation = lttng_evaluation_event_rule_create( + trigger_name); + if (evaluation == NULL) { + ERR("[notification-thread] Failed to create event rule hit evaluation while creating and enqueuing action executor job"); + ret = -1; + goto end_unlock; + } + + client_list = get_client_list_from_condition(state, + lttng_trigger_get_const_condition(element->trigger)); + executor_status = action_executor_enqueue(state->executor, + element->trigger, evaluation, NULL, client_list); + switch (executor_status) { + case ACTION_EXECUTOR_STATUS_OK: + ret = 0; + break; + case ACTION_EXECUTOR_STATUS_OVERFLOW: + { + struct notification_client_list_element *client_list_element, + *tmp; + + /* + * Not a fatal error; this is expected and simply means the + * executor has too much work queued already. + */ + ret = 0; + + /* No clients subscribed to notifications for this trigger. */ + if (!client_list) { + break; + } + + /* Warn clients that a notification (or more) was dropped. */ + pthread_mutex_lock(&client_list->lock); + cds_list_for_each_entry_safe(client_list_element, tmp, + &client_list->list, node) { + enum client_transmission_status transmission_status; + struct notification_client *client = + client_list_element->client; + + pthread_mutex_lock(&client->lock); + ret = client_notification_overflow(client); + if (ret) { + /* Fatal error. */ + goto next_client; + } + + transmission_status = + client_flush_outgoing_queue(client); + ret = client_handle_transmission_status( + client, transmission_status, state); + if (ret) { + /* Fatal error. */ + goto next_client; + } +next_client: + pthread_mutex_unlock(&client->lock); + if (ret) { + break; + } + } + + pthread_mutex_unlock(&client_list->lock); + break; + } + case ACTION_EXECUTOR_STATUS_ERROR: + /* Fatal error, shut down everything. */ + ERR("Fatal error encoutered while enqueuing action to the action executor"); + ret = -1; + goto end_unlock; + default: + /* Unhandled error. */ + abort(); + } end_unlock: + notification_client_list_put(client_list); rcu_read_unlock(); + return ret; +} + +static +int handle_one_event_notifier_notification( + struct notification_thread_state *state, + int pipe, enum lttng_domain_type domain) +{ + int ret; + struct lttng_event_notifier_notification *notification = NULL; + + notification = recv_one_event_notifier_notification(pipe, domain); + if (notification == NULL) { + ERR("[notification-thread] Error receiving an event notifier notification from tracer: fd = %i, domain = %s", + pipe, lttng_domain_type_str(domain)); + ret = -1; + goto end; + } + + ret = dispatch_one_event_notifier_notification(state, notification); + if (ret) { + ERR("[notification-thread] Error dispatching an event notifier notification from tracer: fd = %i, domain = %s", + pipe, lttng_domain_type_str(domain)); + goto end; + } + end: + lttng_event_notifier_notification_destroy(notification); return ret; } +int handle_notification_thread_event_notification(struct notification_thread_state *state, + int pipe, enum lttng_domain_type domain) +{ + return handle_one_event_notifier_notification(state, pipe, domain); +} + int handle_notification_thread_channel_sample( struct notification_thread_state *state, int pipe, enum lttng_domain_type domain) @@ -4319,8 +4507,7 @@ int handle_notification_thread_channel_sample( */ DBG("[notification-thread] Received a sample for an unknown channel from consumerd, key = %" PRIu64 " in %s domain", latest_sample.key.key, - domain == LTTNG_DOMAIN_KERNEL ? "kernel" : - "user space"); + lttng_domain_type_str(domain)); goto end_unlock; } channel_info = caa_container_of(node, struct channel_info,