X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fnotification-thread-events.c;h=823f2a7eb3b2d53a4642844738ebd808445e2f26;hp=a1af9c53526367018c774447837e352f2f349353;hb=b9a8d78fefbc856370939d9eb553d6e9c1fcc86a;hpb=513676343b23fd9743291679cff46756238bf360 diff --git a/src/bin/lttng-sessiond/notification-thread-events.c b/src/bin/lttng-sessiond/notification-thread-events.c index a1af9c535..823f2a7eb 100644 --- a/src/bin/lttng-sessiond/notification-thread-events.c +++ b/src/bin/lttng-sessiond/notification-thread-events.c @@ -26,8 +26,11 @@ #include #include #include +#include +#include #include #include +#include #include #include @@ -35,6 +38,7 @@ #include #include +#include "condition-internal.h" #include "notification-thread.h" #include "notification-thread-events.h" #include "notification-thread-commands.h" @@ -277,6 +281,17 @@ int match_trigger(struct cds_lfht_node *node, const void *key) return !!lttng_trigger_is_equal(trigger_key, trigger_ht_element->trigger); } +static +int match_trigger_token(struct cds_lfht_node *node, const void *key) +{ + const uint64_t *_key = key; + struct notification_trigger_tokens_ht_element *element; + + element = caa_container_of(node, + struct notification_trigger_tokens_ht_element, node); + return *_key == element->token; +} + static int match_client_list_condition(struct cds_lfht_node *node, const void *key) { @@ -303,6 +318,38 @@ int match_session(struct cds_lfht_node *node, const void *key) return !strcmp(session_info->name, name); } +static +const char *notification_command_type_str( + enum notification_thread_command_type type) +{ + switch (type) { + case NOTIFICATION_COMMAND_TYPE_REGISTER_TRIGGER: + return "REGISTER_TRIGGER"; + case NOTIFICATION_COMMAND_TYPE_UNREGISTER_TRIGGER: + return "UNREGISTER_TRIGGER"; + case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL: + return "ADD_CHANNEL"; + case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL: + return "REMOVE_CHANNEL"; + case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING: + return "SESSION_ROTATION_ONGOING"; + case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED: + return "SESSION_ROTATION_COMPLETED"; + case NOTIFICATION_COMMAND_TYPE_ADD_TRACER_EVENT_SOURCE: + return "ADD_TRACER_EVENT_SOURCE"; + case NOTIFICATION_COMMAND_TYPE_REMOVE_TRACER_EVENT_SOURCE: + return "REMOVE_TRACER_EVENT_SOURCE"; + case NOTIFICATION_COMMAND_TYPE_LIST_TRIGGERS: + return "LIST_TRIGGERS"; + case NOTIFICATION_COMMAND_TYPE_QUIT: + return "QUIT"; + case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE: + return "CLIENT_COMMUNICATION_UPDATE"; + default: + abort(); + } +} + /* * Match trigger based on name and credentials only. * Name duplication is NOT allowed for the same uid. @@ -368,105 +415,6 @@ unsigned long hash_trigger_by_name_uid(const struct lttng_trigger *trigger) return hash; } -static -unsigned long lttng_condition_buffer_usage_hash( - const struct lttng_condition *_condition) -{ - unsigned long hash; - unsigned long condition_type; - struct lttng_condition_buffer_usage *condition; - - condition = container_of(_condition, - struct lttng_condition_buffer_usage, parent); - - condition_type = (unsigned long) condition->parent.type; - hash = hash_key_ulong((void *) condition_type, lttng_ht_seed); - if (condition->session_name) { - hash ^= hash_key_str(condition->session_name, lttng_ht_seed); - } - if (condition->channel_name) { - hash ^= hash_key_str(condition->channel_name, lttng_ht_seed); - } - if (condition->domain.set) { - hash ^= hash_key_ulong( - (void *) condition->domain.type, - lttng_ht_seed); - } - if (condition->threshold_ratio.set) { - uint64_t val; - - val = condition->threshold_ratio.value * (double) UINT32_MAX; - hash ^= hash_key_u64(&val, lttng_ht_seed); - } else if (condition->threshold_bytes.set) { - uint64_t val; - - val = condition->threshold_bytes.value; - hash ^= hash_key_u64(&val, lttng_ht_seed); - } - return hash; -} - -static -unsigned long lttng_condition_session_consumed_size_hash( - const struct lttng_condition *_condition) -{ - unsigned long hash; - unsigned long condition_type = - (unsigned long) LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE; - struct lttng_condition_session_consumed_size *condition; - uint64_t val; - - condition = container_of(_condition, - struct lttng_condition_session_consumed_size, parent); - - hash = hash_key_ulong((void *) condition_type, lttng_ht_seed); - if (condition->session_name) { - hash ^= hash_key_str(condition->session_name, lttng_ht_seed); - } - val = condition->consumed_threshold_bytes.value; - hash ^= hash_key_u64(&val, lttng_ht_seed); - return hash; -} - -static -unsigned long lttng_condition_session_rotation_hash( - const struct lttng_condition *_condition) -{ - unsigned long hash, condition_type; - struct lttng_condition_session_rotation *condition; - - condition = container_of(_condition, - struct lttng_condition_session_rotation, parent); - condition_type = (unsigned long) condition->parent.type; - hash = hash_key_ulong((void *) condition_type, lttng_ht_seed); - assert(condition->session_name); - hash ^= hash_key_str(condition->session_name, lttng_ht_seed); - return hash; -} - -/* - * The lttng_condition hashing code is kept in this file (rather than - * condition.c) since it makes use of GPLv2 code (hashtable utils), which we - * don't want to link in liblttng-ctl. - */ -static -unsigned long lttng_condition_hash(const struct lttng_condition *condition) -{ - switch (condition->type) { - case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW: - case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH: - return lttng_condition_buffer_usage_hash(condition); - case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE: - return lttng_condition_session_consumed_size_hash(condition); - case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING: - case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED: - return lttng_condition_session_rotation_hash(condition); - default: - ERR("[notification-thread] Unexpected condition type caught"); - abort(); - } -} - static unsigned long hash_channel_key(struct channel_key *key) { @@ -509,6 +457,8 @@ enum lttng_object_type get_condition_binding_object( case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING: case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED: return LTTNG_OBJECT_TYPE_SESSION; + case LTTNG_CONDITION_TYPE_EVENT_RULE_HIT: + return LTTNG_OBJECT_TYPE_NONE; default: return LTTNG_OBJECT_TYPE_UNKNOWN; } @@ -1019,6 +969,7 @@ int evaluate_condition_for_client(const struct lttng_trigger *trigger, &evaluation, &object_uid, &object_gid); break; case LTTNG_OBJECT_TYPE_NONE: + DBG("[notification-thread] Newly subscribed-to condition not bound to object, nothing to evaluate"); ret = 0; goto end; case LTTNG_OBJECT_TYPE_UNKNOWN: @@ -1690,7 +1641,7 @@ 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); @@ -1791,7 +1742,7 @@ 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(); @@ -1984,6 +1935,126 @@ end: return ret; } +static +int handle_notification_thread_command_add_tracer_event_source( + struct notification_thread_state *state, + int tracer_event_source_fd, + enum lttng_domain_type domain_type, + enum lttng_error_code *_cmd_result) +{ + int ret = 0; + enum lttng_error_code cmd_result = LTTNG_OK; + struct notification_event_tracer_event_source_element *element = NULL; + + element = zmalloc(sizeof(*element)); + if (!element) { + cmd_result = LTTNG_ERR_NOMEM; + ret = -1; + goto end; + } + + element->fd = tracer_event_source_fd; + element->domain = domain_type; + + cds_list_add(&element->node, &state->tracer_event_sources_list); + + DBG3("[notification-thread] Adding tracer event source fd to poll set: tracer_event_source_fd = %d, domain = '%s'", + tracer_event_source_fd, + lttng_domain_type_str(domain_type)); + + /* Adding the read side pipe to the event poll. */ + ret = lttng_poll_add(&state->events, tracer_event_source_fd, LPOLLIN | LPOLLERR); + if (ret < 0) { + ERR("[notification-thread] Failed to add tracer event source to poll set: tracer_event_source_fd = %d, domain = '%s'", + tracer_event_source_fd, + lttng_domain_type_str(element->domain)); + cds_list_del(&element->node); + free(element); + goto end; + } + + element->is_fd_in_poll_set = true; + +end: + *_cmd_result = cmd_result; + return ret; +} + +static +int handle_notification_thread_command_remove_tracer_event_source( + struct notification_thread_state *state, + int tracer_event_source_fd, + enum lttng_error_code *_cmd_result) +{ + int ret = 0; + bool found = false; + enum lttng_error_code cmd_result = LTTNG_OK; + struct notification_event_tracer_event_source_element *source_element = NULL, *tmp; + + cds_list_for_each_entry_safe(source_element, tmp, + &state->tracer_event_sources_list, node) { + if (source_element->fd != tracer_event_source_fd) { + continue; + } + + DBG("[notification-thread] Removed tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'", + tracer_event_source_fd, + lttng_domain_type_str(source_element->domain)); + cds_list_del(&source_element->node); + found = true; + break; + } + + if (!found) { + /* + * This is temporarily allowed since the poll activity set is + * not properly cleaned-up for the moment. This is adressed in + * an upcoming fix. + */ + source_element = NULL; + goto end; + } + + if (!source_element->is_fd_in_poll_set) { + /* Skip the poll set removal. */ + goto end; + } + + DBG3("[notification-thread] Removing tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'", + tracer_event_source_fd, + lttng_domain_type_str(source_element->domain)); + + /* Removing the fd from the event poll set. */ + ret = lttng_poll_del(&state->events, tracer_event_source_fd); + if (ret < 0) { + ERR("[notification-thread] Failed to remove tracer event source from poll set: 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; + } + + source_element->is_fd_in_poll_set = false; + +end: + free(source_element); + *_cmd_result = cmd_result; + return ret; +} + +int handle_notification_thread_remove_tracer_event_source_no_result( + struct notification_thread_state *state, + int tracer_event_source_fd) +{ + int ret; + enum lttng_error_code cmd_result; + + ret = handle_notification_thread_command_remove_tracer_event_source( + state, tracer_event_source_fd, &cmd_result); + (void) cmd_result; + return ret; +} + static int handle_notification_thread_command_list_triggers( struct notification_thread_handle *handle, struct notification_thread_state *state, @@ -2040,25 +2111,23 @@ end: } static -int condition_is_supported(struct lttng_condition *condition) +bool condition_is_supported(struct lttng_condition *condition) { - int ret; + bool is_supported; switch (lttng_condition_get_type(condition)) { case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW: case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH: { + int ret; enum lttng_domain_type domain; ret = lttng_condition_buffer_usage_get_domain_type(condition, &domain); - if (ret) { - ret = -1; - goto end; - } + assert(ret == 0); if (domain != LTTNG_DOMAIN_KERNEL) { - ret = 1; + is_supported = true; goto end; } @@ -2066,15 +2135,43 @@ int condition_is_supported(struct lttng_condition *condition) * Older kernel tracers don't expose the API to monitor their * buffers. Therefore, we reject triggers that require that * mechanism to be available to be evaluated. + * + * Assume unsupported on error. + */ + is_supported = kernel_supports_ring_buffer_snapshot_sample_positions() == 1; + break; + } + case LTTNG_CONDITION_TYPE_EVENT_RULE_HIT: + { + const struct lttng_event_rule *event_rule; + enum lttng_domain_type domain; + const enum lttng_condition_status status = + lttng_condition_event_rule_get_rule( + condition, &event_rule); + + assert(status == LTTNG_CONDITION_STATUS_OK); + + domain = lttng_event_rule_get_domain_type(event_rule); + if (domain != LTTNG_DOMAIN_KERNEL) { + is_supported = true; + goto end; + } + + /* + * Older kernel tracers can't emit notification. Therefore, we + * reject triggers that require that mechanism to be available + * to be evaluated. + * + * Assume unsupported on error. */ - ret = kernel_supports_ring_buffer_snapshot_sample_positions(); + is_supported = kernel_supports_event_notifiers() == 1; break; } default: - ret = 1; + is_supported = true; } end: - return ret; + return is_supported; } /* Must be called with RCU read lock held. */ @@ -2278,6 +2375,7 @@ int handle_notification_thread_command_register_trigger( 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 notification_trigger_tokens_ht_element *trigger_tokens_ht_element = NULL; struct cds_lfht_node *node; struct cds_lfht_iter iter; const char* trigger_name; @@ -2316,15 +2414,10 @@ int handle_notification_thread_command_register_trigger( condition = lttng_trigger_get_condition(trigger); assert(condition); - ret = condition_is_supported(condition); - if (ret < 0) { - goto error; - } else if (ret == 0) { + /* Some conditions require tracers to implement a minimal ABI version. */ + if (!condition_is_supported(condition)) { *cmd_result = LTTNG_ERR_NOT_SUPPORTED; goto error; - } else { - /* Feature is supported, continue. */ - ret = 0; } trigger_ht_element = zmalloc(sizeof(*trigger_ht_element)); @@ -2361,10 +2454,47 @@ int handle_notification_thread_command_register_trigger( goto error_free_ht_element; } + if (lttng_condition_get_type(condition) == LTTNG_CONDITION_TYPE_EVENT_RULE_HIT) { + trigger_tokens_ht_element = zmalloc(sizeof(*trigger_tokens_ht_element)); + if (!trigger_tokens_ht_element) { + /* Fatal error. */ + ret = -1; + cds_lfht_del(state->triggers_ht, + &trigger_ht_element->node); + cds_lfht_del(state->triggers_by_name_uid_ht, + &trigger_ht_element->node_by_name_uid); + goto error_free_ht_element; + } + + /* Add trigger token to the trigger_tokens_ht. */ + cds_lfht_node_init(&trigger_tokens_ht_element->node); + trigger_tokens_ht_element->token = + LTTNG_OPTIONAL_GET(trigger->tracer_token); + trigger_tokens_ht_element->trigger = trigger; + + node = cds_lfht_add_unique(state->trigger_tokens_ht, + hash_key_u64(&trigger_tokens_ht_element->token, + lttng_ht_seed), + match_trigger_token, + &trigger_tokens_ht_element->token, + &trigger_tokens_ht_element->node); + if (node != &trigger_tokens_ht_element->node) { + /* Internal corruption, fatal error. */ + ret = -1; + *cmd_result = LTTNG_ERR_TRIGGER_EXISTS; + cds_lfht_del(state->triggers_ht, + &trigger_ht_element->node); + cds_lfht_del(state->triggers_by_name_uid_ht, + &trigger_ht_element->node_by_name_uid); + goto error_free_ht_element; + } + } + /* * Ownership of the trigger and of its wrapper was transfered to - * the triggers_ht. + * the triggers_ht. Same for token ht element if necessary. */ + trigger_tokens_ht_element = NULL; trigger_ht_element = NULL; free_trigger = false; @@ -2467,11 +2597,15 @@ 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; @@ -2487,9 +2621,6 @@ 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) { @@ -2546,6 +2677,7 @@ error_free_ht_element: free_lttng_trigger_ht_element_rcu); } + free(trigger_tokens_ht_element); error: if (free_trigger) { lttng_trigger_destroy(trigger); @@ -2561,10 +2693,17 @@ void free_lttng_trigger_ht_element_rcu(struct rcu_head *node) rcu_node)); } +static +void free_notification_trigger_tokens_ht_element_rcu(struct rcu_head *node) +{ + free(caa_container_of(node, struct notification_trigger_tokens_ht_element, + rcu_node)); +} + static int handle_notification_thread_command_unregister_trigger( struct notification_thread_state *state, - struct lttng_trigger *trigger, + const struct lttng_trigger *trigger, enum lttng_error_code *_cmd_reply) { struct cds_lfht_iter iter; @@ -2572,7 +2711,7 @@ int handle_notification_thread_command_unregister_trigger( struct lttng_channel_trigger_list *trigger_list; struct notification_client_list *client_list; struct lttng_trigger_ht_element *trigger_ht_element = NULL; - struct lttng_condition *condition = lttng_trigger_get_condition( + const struct lttng_condition *condition = lttng_trigger_get_const_condition( trigger); enum lttng_error_code cmd_reply; @@ -2609,6 +2748,28 @@ int handle_notification_thread_command_unregister_trigger( } } + if (lttng_condition_get_type(condition) == + LTTNG_CONDITION_TYPE_EVENT_RULE_HIT) { + struct notification_trigger_tokens_ht_element + *trigger_tokens_ht_element; + + cds_lfht_for_each_entry (state->trigger_tokens_ht, &iter, + trigger_tokens_ht_element, node) { + if (!lttng_trigger_is_equal(trigger, + trigger_tokens_ht_element->trigger)) { + continue; + } + + DBG("[notification-thread] Removed trigger from tokens_ht"); + cds_lfht_del(state->trigger_tokens_ht, + &trigger_tokens_ht_element->node); + call_rcu(&trigger_tokens_ht_element->rcu_node, + free_notification_trigger_tokens_ht_element_rcu); + + break; + } + } + if (is_trigger_action_notify(trigger)) { /* * Remove and release the client list from @@ -2661,21 +2822,22 @@ int handle_notification_thread_command( struct notification_thread_command, cmd_list_node); cds_list_del(&cmd->cmd_list_node); pthread_mutex_unlock(&handle->cmd_queue.lock); + + DBG("[notification-thread] Received `%s` command", + notification_command_type_str(cmd->type)); switch (cmd->type) { case NOTIFICATION_COMMAND_TYPE_REGISTER_TRIGGER: - DBG("[notification-thread] Received register trigger command"); - ret = handle_notification_thread_command_register_trigger( - state, cmd->parameters.trigger, + ret = handle_notification_thread_command_register_trigger(state, + cmd->parameters.register_trigger.trigger, &cmd->reply_code); break; case NOTIFICATION_COMMAND_TYPE_UNREGISTER_TRIGGER: - DBG("[notification-thread] Received unregister trigger command"); ret = handle_notification_thread_command_unregister_trigger( - state, cmd->parameters.trigger, + state, + cmd->parameters.unregister_trigger.trigger, &cmd->reply_code); break; case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL: - DBG("[notification-thread] Received add channel command"); ret = handle_notification_thread_command_add_channel( state, cmd->parameters.add_channel.session.name, @@ -2688,7 +2850,6 @@ int handle_notification_thread_command( &cmd->reply_code); break; case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL: - DBG("[notification-thread] Received remove channel command"); ret = handle_notification_thread_command_remove_channel( state, cmd->parameters.remove_channel.key, cmd->parameters.remove_channel.domain, @@ -2696,9 +2857,6 @@ int handle_notification_thread_command( break; case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING: case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED: - DBG("[notification-thread] Received session rotation %s command", - cmd->type == NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING ? - "ongoing" : "completed"); ret = handle_notification_thread_command_session_rotation( state, cmd->type, @@ -2709,6 +2867,19 @@ int handle_notification_thread_command( cmd->parameters.session_rotation.location, &cmd->reply_code); break; + case NOTIFICATION_COMMAND_TYPE_ADD_TRACER_EVENT_SOURCE: + ret = handle_notification_thread_command_add_tracer_event_source( + state, + cmd->parameters.tracer_event_source.tracer_event_source_fd, + cmd->parameters.tracer_event_source.domain, + &cmd->reply_code); + break; + case NOTIFICATION_COMMAND_TYPE_REMOVE_TRACER_EVENT_SOURCE: + ret = handle_notification_thread_command_remove_tracer_event_source( + state, + cmd->parameters.tracer_event_source.tracer_event_source_fd, + &cmd->reply_code); + break; case NOTIFICATION_COMMAND_TYPE_LIST_TRIGGERS: { struct lttng_triggers *triggers = NULL; @@ -2724,7 +2895,6 @@ int handle_notification_thread_command( break; } case NOTIFICATION_COMMAND_TYPE_QUIT: - DBG("[notification-thread] Received quit command"); cmd->reply_code = LTTNG_OK; ret = 1; goto end; @@ -3991,6 +4161,199 @@ end: return ret; } +static struct lttng_event_notifier_notification *receive_notification( + int notification_pipe_read_fd, enum lttng_domain_type domain) +{ + int ret; + uint64_t token; + struct lttng_event_notifier_notification *notification = NULL; + void *reception_buffer; + size_t reception_size; + + 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); + break; + case LTTNG_DOMAIN_KERNEL: + reception_buffer = (void *) &kernel_notification; + reception_size = sizeof(kernel_notification); + break; + default: + abort(); + } + + /* + * The monitoring pipe only holds messages smaller than PIPE_BUF, + * ensuring that read/write of tracer notifications are atomic. + */ + ret = lttng_read(notification_pipe_read_fd, reception_buffer, + reception_size); + if (ret != reception_size) { + PERROR("Failed to read from event source notification pipe: fd = %d, size to read = %zu, ret = %d", + notification_pipe_read_fd, reception_size, ret); + ret = -1; + goto end; + } + + switch(domain) { + case LTTNG_DOMAIN_UST: + token = ust_notification.token; + break; + case LTTNG_DOMAIN_KERNEL: + token = kernel_notification.token; + break; + default: + abort(); + } + + notification = lttng_event_notifier_notification_create( + token, domain); +end: + return notification; +} + +int handle_notification_thread_event_notification(struct notification_thread_state *state, + int pipe, + enum lttng_domain_type domain) +{ + int ret; + enum lttng_trigger_status trigger_status; + struct cds_lfht_node *node; + struct cds_lfht_iter iter; + struct notification_trigger_tokens_ht_element *element; + struct lttng_evaluation *evaluation = NULL; + struct lttng_event_notifier_notification *notification = NULL; + enum action_executor_status executor_status; + struct notification_client_list *client_list = NULL; + const char *trigger_name; + + notification = receive_notification(pipe, domain); + if (notification == NULL) { + ERR("[notification-thread] Error receiving notification from tracer (fd = %i, domain = %s)", + pipe, lttng_domain_type_str(domain)); + ret = -1; + goto end; + } + + /* Find triggers associated with this token. */ + rcu_read_lock(); + cds_lfht_lookup(state->trigger_tokens_ht, + 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_unlikely(!node)) { + /* + * 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; + } + + element = caa_container_of(node, + struct notification_trigger_tokens_ht_element, + node); + + if (!lttng_trigger_should_fire(element->trigger)) { + ret = 0; + goto end_unlock; + } + + lttng_trigger_fire(element->trigger); + + 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: + lttng_event_notifier_notification_destroy(notification); + notification_client_list_put(client_list); + rcu_read_unlock(); +end: + return ret; +} + int handle_notification_thread_channel_sample( struct notification_thread_state *state, int pipe, enum lttng_domain_type domain) @@ -4044,8 +4407,7 @@ 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,