X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fnotification-thread-events.c;h=ee20725dd318c3a167053d20b6da2fb03f8fed64;hp=5ec3ed279636cc3ce70a66b05108a68c7510762f;hb=091fa780af74dc1a93eaeff50d8c0baf1de8c41f;hpb=6487ad53bfafc764c432a4378c06d0d840f000ea diff --git a/src/bin/lttng-sessiond/notification-thread-events.c b/src/bin/lttng-sessiond/notification-thread-events.c index 5ec3ed279..ee20725dd 100644 --- a/src/bin/lttng-sessiond/notification-thread-events.c +++ b/src/bin/lttng-sessiond/notification-thread-events.c @@ -122,6 +122,7 @@ struct lttng_trigger_ht_element { struct lttng_trigger *trigger; struct cds_lfht_node node; struct cds_lfht_node node_by_name_uid; + struct cds_list_head client_list_trigger_node; /* call_rcu delayed reclaim. */ struct rcu_head rcu_node; }; @@ -314,7 +315,7 @@ int match_client_list_condition(struct cds_lfht_node *node, const void *key) client_list = caa_container_of(node, struct notification_client_list, notification_trigger_clients_ht_node); - condition = lttng_trigger_get_const_condition(client_list->trigger); + condition = client_list->condition; return !!lttng_condition_is_equal(condition_key, condition); } @@ -661,62 +662,121 @@ void notification_client_list_release(struct urcu_ref *list_ref) container_of(list_ref, typeof(*list), ref); struct notification_client_list_element *client_list_element, *tmp; + lttng_condition_put(list->condition); + if (list->notification_trigger_clients_ht) { rcu_read_lock(); + cds_lfht_del(list->notification_trigger_clients_ht, &list->notification_trigger_clients_ht_node); rcu_read_unlock(); list->notification_trigger_clients_ht = NULL; } cds_list_for_each_entry_safe(client_list_element, tmp, - &list->list, node) { + &list->clients_list, node) { free(client_list_element); } + + assert(cds_list_empty(&list->triggers_list)); + pthread_mutex_destroy(&list->lock); call_rcu(&list->rcu_node, free_notification_client_list_rcu); } +static +bool condition_applies_to_client(const struct lttng_condition *condition, + struct notification_client *client) +{ + bool applies = false; + struct lttng_condition_list_element *condition_list_element; + + cds_list_for_each_entry(condition_list_element, &client->condition_list, + node) { + applies = lttng_condition_is_equal( + condition_list_element->condition, + condition); + if (applies) { + break; + } + } + + return applies; +} + static struct notification_client_list *notification_client_list_create( - const struct lttng_trigger *trigger) + struct notification_thread_state *state, + const struct lttng_condition *condition) { - struct notification_client_list *client_list = - zmalloc(sizeof(*client_list)); + struct notification_client *client; + struct cds_lfht_iter iter; + struct notification_client_list *client_list; + client_list = zmalloc(sizeof(*client_list)); if (!client_list) { - goto error; + PERROR("Failed to allocate notification client list"); + goto end; } + pthread_mutex_init(&client_list->lock, NULL); + /* + * The trigger that owns the condition has the first reference to this + * client list. + */ urcu_ref_init(&client_list->ref); cds_lfht_node_init(&client_list->notification_trigger_clients_ht_node); - CDS_INIT_LIST_HEAD(&client_list->list); - client_list->trigger = trigger; -error: - return client_list; -} + CDS_INIT_LIST_HEAD(&client_list->clients_list); + CDS_INIT_LIST_HEAD(&client_list->triggers_list); -static -void publish_notification_client_list( - struct notification_thread_state *state, - struct notification_client_list *list) -{ - const struct lttng_condition *condition = - lttng_trigger_get_const_condition(list->trigger); + /* + * Create a copy of the condition so that it's independent of any + * trigger. The client list may outlive the trigger object (which owns + * the condition) that is used to create it. + */ + client_list->condition = lttng_condition_copy(condition); + + /* Build a list of clients to which this new condition applies. */ + cds_lfht_for_each_entry (state->client_socket_ht, &iter, client, + client_socket_ht_node) { + struct notification_client_list_element *client_list_element; - assert(!list->notification_trigger_clients_ht); - notification_client_list_get(list); + if (!condition_applies_to_client(condition, client)) { + continue; + } + + client_list_element = zmalloc(sizeof(*client_list_element)); + if (!client_list_element) { + goto error_put_client_list; + } - list->notification_trigger_clients_ht = + CDS_INIT_LIST_HEAD(&client_list_element->node); + client_list_element->client = client; + cds_list_add(&client_list_element->node, &client_list->clients_list); + } + + client_list->notification_trigger_clients_ht = state->notification_trigger_clients_ht; rcu_read_lock(); - cds_lfht_add(state->notification_trigger_clients_ht, - lttng_condition_hash(condition), - &list->notification_trigger_clients_ht_node); + /* + * Add the client list to the global list of client list. + */ + cds_lfht_add_unique(state->notification_trigger_clients_ht, + lttng_condition_hash(client_list->condition), + match_client_list_condition, + client_list->condition, + &client_list->notification_trigger_clients_ht_node); rcu_read_unlock(); + goto end; + +error_put_client_list: + notification_client_list_put(client_list); + client_list = NULL; + +end: + return client_list; } -LTTNG_HIDDEN void notification_client_list_put(struct notification_client_list *list) { if (!list) { @@ -1004,12 +1064,11 @@ int evaluate_condition_for_client(const struct lttng_trigger *trigger, * subscribing. */ cds_lfht_node_init(&client_list.notification_trigger_clients_ht_node); - CDS_INIT_LIST_HEAD(&client_list.list); - client_list.trigger = trigger; + CDS_INIT_LIST_HEAD(&client_list.clients_list); CDS_INIT_LIST_HEAD(&client_list_element.node); client_list_element.client = client; - cds_list_add(&client_list_element.node, &client_list.list); + cds_list_add(&client_list_element.node, &client_list.clients_list); /* Send evaluation result to the newly-subscribed client. */ DBG("[notification-thread] Newly subscribed-to condition evaluated to true, notifying client"); @@ -1083,13 +1142,19 @@ int notification_thread_client_subscribe(struct notification_client *client, * This is correct since the list doesn't own the trigger and the * object is immutable. */ - if (evaluate_condition_for_client(client_list->trigger, condition, - client, state)) { - WARN("[notification-thread] Evaluation of a condition on client subscription failed, aborting."); - ret = -1; - free(client_list_element); - goto end; + struct lttng_trigger_ht_element *trigger_ht_element; + pthread_mutex_lock(&client_list->lock); + cds_list_for_each_entry(trigger_ht_element, + &client_list->triggers_list, client_list_trigger_node) { + if (evaluate_condition_for_client(trigger_ht_element->trigger, condition, + client, state)) { + WARN("[notification-thread] Evaluation of a condition on client subscription failed, aborting."); + ret = -1; + free(client_list_element); + goto end; + } } + pthread_mutex_unlock(&client_list->lock); /* * Add the client to the list of clients interested in a given trigger @@ -1100,7 +1165,7 @@ int notification_thread_client_subscribe(struct notification_client *client, CDS_INIT_LIST_HEAD(&client_list_element->node); pthread_mutex_lock(&client_list->lock); - cds_list_add(&client_list_element->node, &client_list->list); + cds_list_add(&client_list_element->node, &client_list->clients_list); pthread_mutex_unlock(&client_list->lock); end: if (_status) { @@ -1171,7 +1236,7 @@ int notification_thread_client_unsubscribe( pthread_mutex_lock(&client_list->lock); cds_list_for_each_entry_safe(client_list_element, client_tmp, - &client_list->list, node) { + &client_list->clients_list, node) { if (client_list_element->client->id != client->id) { continue; } @@ -1364,25 +1429,6 @@ fail: return false; } -static -bool trigger_applies_to_client(struct lttng_trigger *trigger, - struct notification_client *client) -{ - bool applies = false; - struct lttng_condition_list_element *condition_list_element; - - cds_list_for_each_entry(condition_list_element, &client->condition_list, - node) { - applies = lttng_condition_is_equal( - condition_list_element->condition, - lttng_trigger_get_condition(trigger)); - if (applies) { - break; - } - } - return applies; -} - /* Must be called with RCU read lock held. */ static struct lttng_session_trigger_list *get_session_trigger_list( @@ -2566,12 +2612,9 @@ int handle_notification_thread_command_register_trigger( { int ret = 0; struct lttng_condition *condition; - struct notification_client *client; struct notification_client_list *client_list = NULL; struct lttng_trigger_ht_element *trigger_ht_element = NULL; - struct notification_client_list_element *client_list_element; struct cds_lfht_node *node; - struct cds_lfht_iter iter; const char* trigger_name; bool free_trigger = true; struct lttng_evaluation *evaluation = NULL; @@ -2670,58 +2713,50 @@ int handle_notification_thread_command_register_trigger( } } - /* - * Ownership of the trigger and of its wrapper was transfered to - * the triggers_ht. Same for token ht element if necessary. - */ - trigger_ht_element = NULL; - free_trigger = false; - /* * The rest only applies to triggers that have a "notify" action. * It is not skipped as this is the only action type currently * supported. */ if (is_trigger_action_notify(trigger)) { - client_list = notification_client_list_create(trigger); + /* + * Find or create the client list of this condition. It may + * already be present if another trigger is already registered + * with the same condition. + */ + client_list = get_client_list_from_condition(state, condition); if (!client_list) { - ret = -1; - goto error_free_ht_element; - } - - /* Build a list of clients to which this new trigger applies. */ - cds_lfht_for_each_entry (state->client_socket_ht, &iter, client, - client_socket_ht_node) { - if (!trigger_applies_to_client(trigger, client)) { - continue; - } - - client_list_element = - zmalloc(sizeof(*client_list_element)); - if (!client_list_element) { - ret = -1; - goto error_put_client_list; + /* + * No client list for this condition yet. We create new + * one and build it up. + */ + client_list = notification_client_list_create(state, condition); + if (!client_list) { + ERR("Error creating notification client list for trigger %s", trigger->name); + goto error_free_ht_element; } - - CDS_INIT_LIST_HEAD(&client_list_element->node); - client_list_element->client = client; - cds_list_add(&client_list_element->node, - &client_list->list); } - /* - * Client list ownership transferred to the - * notification_trigger_clients_ht. - */ - publish_notification_client_list(state, client_list); + CDS_INIT_LIST_HEAD(&trigger_ht_element->client_list_trigger_node); + + pthread_mutex_lock(&client_list->lock); + cds_list_add(&trigger_ht_element->client_list_trigger_node, &client_list->triggers_list); + pthread_mutex_unlock(&client_list->lock); } + /* + * Ownership of the trigger and of its wrapper was transfered to + * the triggers_ht. Same for token ht element if necessary. + */ + trigger_ht_element = NULL; + free_trigger = false; + switch (get_condition_binding_object(condition)) { case LTTNG_OBJECT_TYPE_SESSION: /* Add the trigger to the list if it matches a known session. */ ret = bind_trigger_to_matching_session(trigger, state); if (ret) { - goto error_put_client_list; + goto error_free_ht_element; } break; case LTTNG_OBJECT_TYPE_CHANNEL: @@ -2731,7 +2766,7 @@ int handle_notification_thread_command_register_trigger( */ ret = bind_trigger_to_matching_channels(trigger, state); if (ret) { - goto error_put_client_list; + goto error_free_ht_element; } break; case LTTNG_OBJECT_TYPE_NONE: @@ -2739,7 +2774,7 @@ int handle_notification_thread_command_register_trigger( default: ERR("Unknown object type on which to bind a newly registered trigger was encountered"); ret = -1; - goto error_put_client_list; + goto error_free_ht_element; } /* @@ -2797,7 +2832,7 @@ int handle_notification_thread_command_register_trigger( if (ret) { /* Fatal error. */ - goto error_put_client_list; + goto error_free_ht_element; } DBG("Newly registered trigger's condition evaluated to %s", @@ -2805,7 +2840,7 @@ int handle_notification_thread_command_register_trigger( if (!evaluation) { /* Evaluation yielded nothing. Normal exit. */ ret = 0; - goto end; + goto success; } /* @@ -2826,7 +2861,7 @@ int handle_notification_thread_command_register_trigger( */ ERR("Fatal error occurred while enqueuing action associated to newly registered trigger"); ret = -1; - goto error_put_client_list; + goto error_free_ht_element; case ACTION_EXECUTOR_STATUS_OVERFLOW: /* * TODO Add trigger identification (name/id) when @@ -2836,18 +2871,16 @@ int handle_notification_thread_command_register_trigger( */ WARN("No space left when enqueuing action associated to newly registered trigger"); ret = 0; - goto end; + goto success; default: abort(); } -end: +success: *cmd_result = LTTNG_OK; DBG("Registered trigger: name = `%s`, tracer token = %" PRIu64, trigger_name, trigger_tracer_token); - -error_put_client_list: - notification_client_list_put(client_list); + goto end; error_free_ht_element: if (trigger_ht_element) { @@ -2859,6 +2892,7 @@ error: if (free_trigger) { lttng_trigger_destroy(trigger); } +end: rcu_read_unlock(); return ret; } @@ -2959,6 +2993,9 @@ int handle_notification_thread_command_unregister_trigger( teardown_tracer_notifier(state, trigger); } + trigger_ht_element = caa_container_of(triggers_ht_node, + struct lttng_trigger_ht_element, node); + if (is_trigger_action_notify(trigger)) { /* * Remove and release the client list from @@ -2967,15 +3004,16 @@ int handle_notification_thread_command_unregister_trigger( client_list = get_client_list_from_condition(state, condition); assert(client_list); + pthread_mutex_lock(&client_list->lock); + cds_list_del(&trigger_ht_element->client_list_trigger_node); + pthread_mutex_unlock(&client_list->lock); + /* Put new reference and the hashtable's reference. */ notification_client_list_put(client_list); notification_client_list_put(client_list); client_list = NULL; } - trigger_ht_element = caa_container_of(triggers_ht_node, - struct lttng_trigger_ht_element, node); - /* Remove trigger from triggers_ht. */ notif_thread_state_remove_trigger_ht_elem(state, trigger_ht_element); @@ -4266,7 +4304,7 @@ int notification_client_list_send_evaluation( pthread_mutex_lock(&client_list->lock); cds_list_for_each_entry_safe(client_list_element, tmp, - &client_list->list, node) { + &client_list->clients_list, node) { enum client_transmission_status transmission_status; struct notification_client *client = client_list_element->client; @@ -4548,7 +4586,7 @@ int dispatch_one_event_notifier_notification(struct notification_thread_state *s /* 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) { + &client_list->clients_list, node) { enum client_transmission_status transmission_status; struct notification_client *client = client_list_element->client;