X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fnotification-thread-events.c;h=1a71131f0f90d398c37468db093372a3449120e8;hp=285bcf951aafe3a5bb2801777e7a13eb06dc5ec7;hb=ac16173e318279dee29504820e3c2ad8ea597712;hpb=505b2d90aa87592186ecc2a119cf67fb3f90d168 diff --git a/src/bin/lttng-sessiond/notification-thread-events.c b/src/bin/lttng-sessiond/notification-thread-events.c index 285bcf951..1a71131f0 100644 --- a/src/bin/lttng-sessiond/notification-thread-events.c +++ b/src/bin/lttng-sessiond/notification-thread-events.c @@ -5,6 +5,8 @@ * */ +#include "lttng/action/action.h" +#include "lttng/trigger/trigger-internal.h" #define _LGPL_SOURCE #include #include @@ -24,7 +26,11 @@ #include #include #include +#include +#include #include +#include +#include #include #include @@ -32,6 +38,7 @@ #include #include +#include "condition-internal.h" #include "notification-thread.h" #include "notification-thread-events.h" #include "notification-thread-commands.h" @@ -50,7 +57,7 @@ enum lttng_object_type { struct lttng_trigger_list_element { /* No ownership of the trigger object is assumed. */ - const struct lttng_trigger *trigger; + struct lttng_trigger *trigger; struct cds_list_head node; }; @@ -108,6 +115,7 @@ struct lttng_session_trigger_list { struct lttng_trigger_ht_element { struct lttng_trigger *trigger; struct cds_lfht_node node; + struct cds_lfht_node node_by_name_uid; /* call_rcu delayed reclaim. */ struct rcu_head rcu_node; }; @@ -117,122 +125,6 @@ struct lttng_condition_list_element { struct cds_list_head node; }; -struct notification_client_list_element { - struct notification_client *client; - struct cds_list_head node; -}; - -/* - * Thread safety of notification_client and notification_client_list. - * - * The notification thread (main thread) and the action executor - * interact through client lists. Hence, when the action executor - * thread looks-up the list of clients subscribed to a given - * condition, it will acquire a reference to the list and lock it - * while attempting to communicate with the various clients. - * - * It is not necessary to reference-count clients as they are guaranteed - * to be 'alive' if they are present in a list and that list is locked. Indeed, - * removing references to the client from those subscription lists is part of - * the work performed on destruction of a client. - * - * No provision for other access scenarios are taken into account; - * this is the bare minimum to make these accesses safe and the - * notification thread's state is _not_ "thread-safe" in any general - * sense. - */ -struct notification_client_list { - pthread_mutex_t lock; - struct urcu_ref ref; - const struct lttng_trigger *trigger; - struct cds_list_head list; - /* Weak reference to container. */ - struct cds_lfht *notification_trigger_clients_ht; - struct cds_lfht_node notification_trigger_clients_ht_node; - /* call_rcu delayed reclaim. */ - struct rcu_head rcu_node; -}; - -struct notification_client { - /* Nests within the notification_client_list lock. */ - pthread_mutex_t lock; - notification_client_id id; - int socket; - /* Client protocol version. */ - uint8_t major, minor; - uid_t uid; - gid_t gid; - /* - * Indicates if the credentials and versions of the client have been - * checked. - */ - bool validated; - /* - * Conditions to which the client's notification channel is subscribed. - * List of struct lttng_condition_list_node. The condition member is - * owned by the client. - */ - struct cds_list_head condition_list; - struct cds_lfht_node client_socket_ht_node; - struct cds_lfht_node client_id_ht_node; - struct { - /* - * If a client's communication is inactive, it means that a - * fatal error has occurred (could be either a protocol error or - * the socket API returned a fatal error). No further - * communication should be attempted; the client is queued for - * clean-up. - */ - bool active; - struct { - /* - * During the reception of a message, the reception - * buffers' "size" is set to contain the current - * message's complete payload. - */ - struct lttng_dynamic_buffer buffer; - /* Bytes left to receive for the current message. */ - size_t bytes_to_receive; - /* Type of the message being received. */ - enum lttng_notification_channel_message_type msg_type; - /* - * Indicates whether or not credentials are expected - * from the client. - */ - bool expect_creds; - /* - * Indicates whether or not credentials were received - * from the client. - */ - bool creds_received; - /* Only used during credentials reception. */ - lttng_sock_cred creds; - } inbound; - struct { - /* - * Indicates whether or not a notification addressed to - * this client was dropped because a command reply was - * already buffered. - * - * A notification is dropped whenever the buffer is not - * empty. - */ - bool dropped_notification; - /* - * Indicates whether or not a command reply is already - * buffered. In this case, it means that the client is - * not consuming command replies before emitting a new - * one. This could be caused by a protocol error or a - * misbehaving/malicious client. - */ - bool queued_command_reply; - struct lttng_dynamic_buffer buffer; - } outbound; - } communication; - /* call_rcu delayed reclaim. */ - struct rcu_head rcu_node; -}; - struct channel_state_sample { struct channel_key key; struct cds_lfht_node channel_state_ht_node; @@ -293,8 +185,16 @@ void lttng_session_trigger_list_destroy( struct lttng_session_trigger_list *list); static int lttng_session_trigger_list_add(struct lttng_session_trigger_list *list, - const struct lttng_trigger *trigger); + struct lttng_trigger *trigger); +static +int client_handle_transmission_status( + struct notification_client *client, + enum client_transmission_status transmission_status, + struct notification_thread_state *state); + +static +void free_lttng_trigger_ht_element_rcu(struct rcu_head *node); static int match_client_socket(struct cds_lfht_node *node, const void *key) @@ -370,18 +270,26 @@ int match_channel_info(struct cds_lfht_node *node, const void *key) } static -int match_condition(struct cds_lfht_node *node, const void *key) +int match_trigger(struct cds_lfht_node *node, const void *key) { - struct lttng_condition *condition_key = (struct lttng_condition *) key; - struct lttng_trigger_ht_element *trigger; - struct lttng_condition *condition; + struct lttng_trigger *trigger_key = (struct lttng_trigger *) key; + struct lttng_trigger_ht_element *trigger_ht_element; - trigger = caa_container_of(node, struct lttng_trigger_ht_element, + trigger_ht_element = caa_container_of(node, struct lttng_trigger_ht_element, node); - condition = lttng_trigger_get_condition(trigger->trigger); - assert(condition); - return !!lttng_condition_is_equal(condition_key, condition); + 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 @@ -410,105 +318,71 @@ int match_session(struct cds_lfht_node *node, const void *key) return !strcmp(session_info->name, name); } +/* + * Match trigger based on name and credentials only. + * Name duplication is NOT allowed for the same uid. + */ static -unsigned long lttng_condition_buffer_usage_hash( - const struct lttng_condition *_condition) +int match_trigger_by_name_uid(struct cds_lfht_node *node, + const void *key) { - 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); + bool match = false; + const char *name; + const char *key_name; + enum lttng_trigger_status status; + const struct lttng_credentials *key_creds; + const struct lttng_credentials *node_creds; + const struct lttng_trigger *trigger_key = + (const struct lttng_trigger *) key; + const struct lttng_trigger_ht_element *trigger_ht_element = + caa_container_of(node, + struct lttng_trigger_ht_element, + node_by_name_uid); + + status = lttng_trigger_get_name(trigger_ht_element->trigger, &name); + assert(status == LTTNG_TRIGGER_STATUS_OK); + + status = lttng_trigger_get_name(trigger_key, &key_name); + assert(status == LTTNG_TRIGGER_STATUS_OK); + + /* Compare the names. */ + if (strcmp(name, key_name) != 0) { + goto end; } - 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; + /* Compare the owners' UIDs. */ + key_creds = lttng_trigger_get_credentials(trigger_key); + node_creds = lttng_trigger_get_credentials(trigger_ht_element->trigger); - val = condition->threshold_bytes.value; - hash ^= hash_key_u64(&val, lttng_ht_seed); - } - return hash; + match = lttng_credentials_is_equal_uid(key_creds, node_creds); + +end: + return match; } +/* + * Hash trigger based on name and credentials only. + */ static -unsigned long lttng_condition_session_consumed_size_hash( - const struct lttng_condition *_condition) +unsigned long hash_trigger_by_name_uid(const struct lttng_trigger *trigger) { - 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); + unsigned long hash = 0; + const struct lttng_credentials *trigger_creds; + const char *trigger_name; + enum lttng_trigger_status status; - hash = hash_key_ulong((void *) condition_type, lttng_ht_seed); - if (condition->session_name) { - hash ^= hash_key_str(condition->session_name, lttng_ht_seed); + status = lttng_trigger_get_name(trigger, &trigger_name); + if (status == LTTNG_TRIGGER_STATUS_OK) { + hash = hash_key_str(trigger_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; + trigger_creds = lttng_trigger_get_credentials(trigger); + hash ^= hash_key_ulong((void *) (unsigned long) LTTNG_OPTIONAL_GET(trigger_creds->uid), + lttng_ht_seed); - 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) { @@ -551,6 +425,8 @@ 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; } @@ -722,7 +598,7 @@ error: return NULL; } -static +LTTNG_HIDDEN bool notification_client_list_get(struct notification_client_list *list) { return urcu_ref_get_unless_zero(&list->ref); @@ -785,6 +661,7 @@ void publish_notification_client_list( lttng_trigger_get_const_condition(list->trigger); assert(!list->notification_trigger_clients_ht); + notification_client_list_get(list); list->notification_trigger_clients_ht = state->notification_trigger_clients_ht; @@ -796,7 +673,7 @@ void publish_notification_client_list( rcu_read_unlock(); } -static +LTTNG_HIDDEN void notification_client_list_put(struct notification_client_list *list) { if (!list) { @@ -1060,6 +937,7 @@ 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: @@ -1292,8 +1170,8 @@ void notification_client_destroy(struct notification_client *client, client->socket = -1; } client->communication.active = false; - lttng_dynamic_buffer_reset(&client->communication.inbound.buffer); - lttng_dynamic_buffer_reset(&client->communication.outbound.buffer); + lttng_payload_reset(&client->communication.inbound.payload); + lttng_payload_reset(&client->communication.outbound.payload); pthread_mutex_destroy(&client->lock); call_rcu(&client->rcu_node, free_notification_client_rcu); } @@ -1326,6 +1204,34 @@ end: return client; } +/* + * Call with rcu_read_lock held (and hold for the lifetime of the returned + * client pointer). + */ +static +struct notification_client *get_client_from_id(notification_client_id id, + struct notification_thread_state *state) +{ + struct cds_lfht_iter iter; + struct cds_lfht_node *node; + struct notification_client *client = NULL; + + cds_lfht_lookup(state->client_id_ht, + hash_client_id(id), + match_client_id, + &id, + &iter); + node = cds_lfht_iter_get_node(&iter); + if (!node) { + goto end; + } + + client = caa_container_of(node, struct notification_client, + client_id_ht_node); +end: + return client; +} + static bool buffer_usage_condition_applies_to_channel( const struct lttng_condition *condition, @@ -1529,7 +1435,7 @@ void lttng_session_trigger_list_destroy(struct lttng_session_trigger_list *list) static int lttng_session_trigger_list_add(struct lttng_session_trigger_list *list, - const struct lttng_trigger *trigger) + struct lttng_trigger *trigger) { int ret = 0; struct lttng_trigger_list_element *new_element = @@ -1886,6 +1792,10 @@ int handle_notification_thread_command_session_rotation( struct lttng_session_trigger_list *trigger_list; struct lttng_trigger_list_element *trigger_list_element; struct session_info *session_info; + const struct lttng_credentials session_creds = { + .uid = LTTNG_OPTIONAL_INIT_VALUE(session_uid), + .gid = LTTNG_OPTIONAL_INIT_VALUE(session_gid), + }; rcu_read_lock(); @@ -1911,12 +1821,11 @@ int handle_notification_thread_command_session_rotation( cds_list_for_each_entry(trigger_list_element, &trigger_list->list, node) { const struct lttng_condition *condition; - const struct lttng_action *action; - const struct lttng_trigger *trigger; + struct lttng_trigger *trigger; struct notification_client_list *client_list; struct lttng_evaluation *evaluation = NULL; enum lttng_condition_type condition_type; - bool client_list_is_empty; + enum action_executor_status executor_status; trigger = trigger_list_element->trigger; condition = lttng_trigger_get_const_condition(trigger); @@ -1931,26 +1840,7 @@ int handle_notification_thread_command_session_rotation( continue; } - action = lttng_trigger_get_const_action(trigger); - - /* Notify actions are the only type currently supported. */ - assert(lttng_action_get_type_const(action) == - LTTNG_ACTION_TYPE_NOTIFY); - client_list = get_client_list_from_condition(state, condition); - assert(client_list); - - pthread_mutex_lock(&client_list->lock); - client_list_is_empty = cds_list_empty(&client_list->list); - pthread_mutex_unlock(&client_list->lock); - if (client_list_is_empty) { - /* - * No clients interested in the evaluation's result, - * skip it. - */ - continue; - } - if (cmd_type == NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING) { evaluation = lttng_evaluation_session_rotation_ongoing_create( trace_archive_chunk_id); @@ -1966,12 +1856,40 @@ int handle_notification_thread_command_session_rotation( goto put_list; } - /* Dispatch evaluation result to all clients. */ - ret = send_evaluation_to_clients(trigger_list_element->trigger, - evaluation, client_list, state, - session_info->uid, - session_info->gid); - lttng_evaluation_destroy(evaluation); + /* + * Ownership of `evaluation` transferred to the action executor + * no matter the result. + */ + executor_status = action_executor_enqueue(state->executor, + trigger, evaluation, &session_creds, + client_list); + evaluation = NULL; + switch (executor_status) { + case ACTION_EXECUTOR_STATUS_OK: + break; + case ACTION_EXECUTOR_STATUS_ERROR: + case ACTION_EXECUTOR_STATUS_INVALID: + /* + * TODO Add trigger identification (name/id) when + * it is added to the API. + */ + ERR("Fatal error occurred while enqueuing action associated with session rotation trigger"); + ret = -1; + goto put_list; + case ACTION_EXECUTOR_STATUS_OVERFLOW: + /* + * TODO Add trigger identification (name/id) when + * it is added to the API. + * + * Not a fatal error. + */ + WARN("No space left when enqueuing action associated with session rotation trigger"); + ret = 0; + goto put_list; + default: + abort(); + } + put_list: notification_client_list_put(client_list); if (caa_unlikely(ret)) { @@ -1986,25 +1904,198 @@ end: } static -int condition_is_supported(struct lttng_condition *condition) +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, + uid_t client_uid, + struct lttng_triggers **triggers, + enum lttng_error_code *_cmd_result) +{ + int ret = 0; + enum lttng_error_code cmd_result = LTTNG_OK; + struct cds_lfht_iter iter; + struct lttng_trigger_ht_element *trigger_ht_element; + struct lttng_triggers *local_triggers = NULL; + const struct lttng_credentials *creds; + + rcu_read_lock(); + + local_triggers = lttng_triggers_create(); + if (!local_triggers) { + /* Not a fatal error. */ + cmd_result = LTTNG_ERR_NOMEM; + goto end; + } + + cds_lfht_for_each_entry(state->triggers_ht, &iter, + trigger_ht_element, node) { + /* + * Only return the triggers to which the client has access. + * The root user has visibility over all triggers. + */ + creds = lttng_trigger_get_credentials(trigger_ht_element->trigger); + if (client_uid != lttng_credentials_get_uid(creds) && client_uid != 0) { + continue; + } + + ret = lttng_triggers_add(local_triggers, + trigger_ht_element->trigger); + if (ret < 0) { + /* Not a fatal error. */ + ret = 0; + cmd_result = LTTNG_ERR_NOMEM; + goto end; + } + } + + /* Transferring ownership to the caller. */ + *triggers = local_triggers; + local_triggers = NULL; + +end: + rcu_read_unlock(); + lttng_triggers_destroy(local_triggers); + *_cmd_result = cmd_result; + return ret; +} + +static +bool condition_is_supported(struct lttng_condition *condition) +{ + 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; } @@ -2012,20 +2103,48 @@ 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. */ static -int bind_trigger_to_matching_session(const struct lttng_trigger *trigger, +int bind_trigger_to_matching_session(struct lttng_trigger *trigger, struct notification_thread_state *state) { int ret = 0; @@ -2071,7 +2190,7 @@ end: /* Must be called with RCU read lock held. */ static -int bind_trigger_to_matching_channels(const struct lttng_trigger *trigger, +int bind_trigger_to_matching_channels(struct lttng_trigger *trigger, struct notification_thread_state *state) { int ret = 0; @@ -2115,19 +2234,100 @@ end: return ret; } -/* - * FIXME A client's credentials are not checked when registering a trigger, nor - * are they stored alongside with the trigger. - * - * The effects of this are benign since: - * - The client will succeed in registering the trigger, as it is valid, - * - The trigger will, internally, be bound to the channel/session, - * - The notifications will not be sent since the client's credentials - * are checked against the channel at that moment. - * - * If this function returns a non-zero value, it means something is - * fundamentally broken and the whole subsystem/thread will be torn down. - * +static +bool is_trigger_action_notify(const struct lttng_trigger *trigger) +{ + bool is_notify = false; + unsigned int i, count; + enum lttng_action_status action_status; + const struct lttng_action *action = + lttng_trigger_get_const_action(trigger); + enum lttng_action_type action_type; + + assert(action); + action_type = lttng_action_get_type(action); + if (action_type == LTTNG_ACTION_TYPE_NOTIFY) { + is_notify = true; + goto end; + } else if (action_type != LTTNG_ACTION_TYPE_GROUP) { + goto end; + } + + action_status = lttng_action_group_get_count(action, &count); + assert(action_status == LTTNG_ACTION_STATUS_OK); + + for (i = 0; i < count; i++) { + const struct lttng_action *inner_action = + lttng_action_group_get_at_index( + action, i); + + action_type = lttng_action_get_type(inner_action); + if (action_type == LTTNG_ACTION_TYPE_NOTIFY) { + is_notify = true; + goto end; + } + } + +end: + return is_notify; +} + +static bool trigger_name_taken(struct notification_thread_state *state, + const struct lttng_trigger *trigger) +{ + struct cds_lfht_iter iter; + + /* + * No duplicata is allowed in the triggers_by_name_uid_ht. + * The match is done against the trigger name and uid. + */ + cds_lfht_lookup(state->triggers_by_name_uid_ht, + hash_trigger_by_name_uid(trigger), + match_trigger_by_name_uid, + trigger, + &iter); + return !!cds_lfht_iter_get_node(&iter); +} + +static +enum lttng_error_code generate_trigger_name( + struct notification_thread_state *state, + struct lttng_trigger *trigger, const char **name) +{ + enum lttng_error_code ret_code = LTTNG_OK; + bool taken = false; + enum lttng_trigger_status status; + + do { + const int ret = lttng_trigger_generate_name(trigger, + state->trigger_id.name_offset++); + if (ret) { + /* The only reason this can fail right now. */ + ret_code = LTTNG_ERR_NOMEM; + break; + } + + status = lttng_trigger_get_name(trigger, name); + assert(status == LTTNG_TRIGGER_STATUS_OK); + + taken = trigger_name_taken(state, trigger); + } while (taken || state->trigger_id.name_offset == UINT64_MAX); + + return ret_code; +} + +/* + * FIXME A client's credentials are not checked when registering a trigger. + * + * The effects of this are benign since: + * - The client will succeed in registering the trigger, as it is valid, + * - The trigger will, internally, be bound to the channel/session, + * - The notifications will not be sent since the client's credentials + * are checked against the channel at that moment. + * + * If this function returns a non-zero value, it means something is + * fundamentally broken and the whole subsystem/thread will be torn down. + * * If a non-fatal error occurs, just set the cmd_result to the appropriate * error code. */ @@ -2142,25 +2342,50 @@ int handle_notification_thread_command_register_trigger( 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, *tmp; + 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; bool free_trigger = true; + struct lttng_evaluation *evaluation = NULL; + struct lttng_credentials object_creds; + uid_t object_uid; + gid_t object_gid; + enum action_executor_status executor_status; + const uint64_t trigger_tracer_token = + state->trigger_id.next_tracer_token++; rcu_read_lock(); + /* Set the trigger's tracer token. */ + lttng_trigger_set_tracer_token(trigger, trigger_tracer_token); + + if (lttng_trigger_get_name(trigger, &trigger_name) == + LTTNG_TRIGGER_STATUS_UNSET) { + const enum lttng_error_code ret_code = generate_trigger_name( + state, trigger, &trigger_name); + + if (ret_code != LTTNG_OK) { + /* Fatal error. */ + ret = -1; + *cmd_result = ret_code; + goto error; + } + } else if (trigger_name_taken(state, trigger)) { + /* Not a fatal error. */ + *cmd_result = LTTNG_ERR_TRIGGER_EXISTS; + ret = 0; + goto error; + } + 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)); @@ -2171,12 +2396,13 @@ int handle_notification_thread_command_register_trigger( /* Add trigger to the trigger_ht. */ cds_lfht_node_init(&trigger_ht_element->node); + cds_lfht_node_init(&trigger_ht_element->node_by_name_uid); trigger_ht_element->trigger = trigger; node = cds_lfht_add_unique(state->triggers_ht, lttng_condition_hash(condition), - match_condition, - condition, + match_trigger, + trigger, &trigger_ht_element->node); if (node != &trigger_ht_element->node) { /* Not a fatal error, simply report it to the client. */ @@ -2184,10 +2410,59 @@ int handle_notification_thread_command_register_trigger( goto error_free_ht_element; } + node = cds_lfht_add_unique(state->triggers_by_name_uid_ht, + hash_trigger_by_name_uid(trigger), + match_trigger_by_name_uid, + trigger, + &trigger_ht_element->node_by_name_uid); + if (node != &trigger_ht_element->node_by_name_uid) { + /* Not a fatal error, simply report it to the client. */ + cds_lfht_del(state->triggers_ht, &trigger_ht_element->node); + *cmd_result = LTTNG_ERR_TRIGGER_EXISTS; + 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; @@ -2196,27 +2471,38 @@ int handle_notification_thread_command_register_trigger( * It is not skipped as this is the only action type currently * supported. */ - client_list = notification_client_list_create(trigger); - 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; + if (is_trigger_action_notify(trigger)) { + client_list = notification_client_list_create(trigger); + if (!client_list) { + ret = -1; + goto error_free_ht_element; } - client_list_element = zmalloc(sizeof(*client_list_element)); - if (!client_list_element) { - ret = -1; - goto error_put_client_list; + /* 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; + } + + CDS_INIT_LIST_HEAD(&client_list_element->node); + client_list_element->client = client; + cds_list_add(&client_list_element->node, + &client_list->list); } - 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); } switch (get_condition_binding_object(condition)) { @@ -2240,15 +2526,18 @@ int handle_notification_thread_command_register_trigger( case LTTNG_OBJECT_TYPE_NONE: break; default: - ERR("[notification-thread] Unknown object type on which to bind a newly registered trigger was encountered"); + ERR("Unknown object type on which to bind a newly registered trigger was encountered"); ret = -1; goto error_put_client_list; } /* - * Since there is nothing preventing clients from subscribing to a - * condition before the corresponding trigger is registered, we have - * to evaluate this new condition right away. + * The new trigger's condition must be evaluated against the current + * state. + * + * In the case of `notify` action, nothing preventing clients from + * subscribing to a condition before the corresponding trigger is + * registered, we have to evaluate this new condition right away. * * At some point, we were waiting for the next "evaluation" (e.g. on * reception of a channel sample) to evaluate this new condition, but @@ -2270,32 +2559,92 @@ int handle_notification_thread_command_register_trigger( * current state. Otherwise, the next evaluation cycle may only see * that the evaluations remain the same (true for samples n-1 and n) and * the client will never know that the condition has been met. - * - * No need to lock the list here as it has not been published yet. */ - cds_list_for_each_entry_safe(client_list_element, tmp, - &client_list->list, node) { - ret = evaluate_condition_for_client(trigger, condition, - client_list_element->client, state); - if (ret) { - goto error_put_client_list; - } + switch (get_condition_binding_object(condition)) { + case LTTNG_OBJECT_TYPE_SESSION: + ret = evaluate_session_condition_for_client(condition, state, + &evaluation, &object_uid, + &object_gid); + break; + case LTTNG_OBJECT_TYPE_CHANNEL: + ret = evaluate_channel_condition_for_client(condition, state, + &evaluation, &object_uid, + &object_gid); + break; + case LTTNG_OBJECT_TYPE_NONE: + ret = 0; + break; + case LTTNG_OBJECT_TYPE_UNKNOWN: + default: + ret = -1; + break; + } + + if (ret) { + /* Fatal error. */ + 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) { + /* Evaluation yielded nothing. Normal exit. */ + ret = 0; + goto end; } /* - * Client list ownership transferred to the - * notification_trigger_clients_ht. + * Ownership of `evaluation` transferred to the action executor + * no matter the result. */ - publish_notification_client_list(state, client_list); - client_list = NULL; + executor_status = action_executor_enqueue(state->executor, trigger, + evaluation, &object_creds, client_list); + evaluation = NULL; + switch (executor_status) { + case ACTION_EXECUTOR_STATUS_OK: + break; + case ACTION_EXECUTOR_STATUS_ERROR: + case ACTION_EXECUTOR_STATUS_INVALID: + /* + * TODO Add trigger identification (name/id) when + * it is added to the API. + */ + ERR("Fatal error occurred while enqueuing action associated to newly registered trigger"); + ret = -1; + goto error_put_client_list; + case ACTION_EXECUTOR_STATUS_OVERFLOW: + /* + * TODO Add trigger identification (name/id) when + * it is added to the API. + * + * Not a fatal error. + */ + WARN("No space left when enqueuing action associated to newly registered trigger"); + ret = 0; + goto end; + default: + abort(); + } +end: *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); error_free_ht_element: - free(trigger_ht_element); + if (trigger_ht_element) { + /* Delayed removal due to RCU constraint on delete. */ + call_rcu(&trigger_ht_element->rcu_node, + free_lttng_trigger_ht_element_rcu); + } + + free(trigger_tokens_ht_element); error: if (free_trigger) { lttng_trigger_destroy(trigger); @@ -2311,10 +2660,17 @@ 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; @@ -2322,7 +2678,7 @@ 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; @@ -2330,8 +2686,8 @@ int handle_notification_thread_command_unregister_trigger( cds_lfht_lookup(state->triggers_ht, lttng_condition_hash(condition), - match_condition, - condition, + match_trigger, + trigger, &iter); triggers_ht_node = cds_lfht_iter_get_node(&iter); if (!triggers_ht_node) { @@ -2348,13 +2704,7 @@ int handle_notification_thread_command_unregister_trigger( cds_list_for_each_entry_safe(trigger_element, tmp, &trigger_list->list, node) { - const struct lttng_condition *current_condition = - lttng_trigger_get_const_condition( - trigger_element->trigger); - - assert(current_condition); - if (!lttng_condition_is_equal(condition, - current_condition)) { + if (!lttng_trigger_is_equal(trigger, trigger_element->trigger)) { continue; } @@ -2365,21 +2715,46 @@ int handle_notification_thread_command_unregister_trigger( } } - /* - * Remove and release the client list from - * notification_trigger_clients_ht. - */ - client_list = get_client_list_from_condition(state, condition); - assert(client_list); + if (lttng_condition_get_type(condition) == + LTTNG_CONDITION_TYPE_EVENT_RULE_HIT) { + struct notification_trigger_tokens_ht_element + *trigger_tokens_ht_element; - /* Put new reference and the hashtable's reference. */ - notification_client_list_put(client_list); - notification_client_list_put(client_list); - client_list = NULL; + 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 + * notification_trigger_clients_ht. + */ + client_list = get_client_list_from_condition(state, condition); + assert(client_list); + + /* Put new reference and the hashtable's reference. */ + notification_client_list_put(client_list); + notification_client_list_put(client_list); + client_list = NULL; + } /* Remove trigger from triggers_ht. */ trigger_ht_element = caa_container_of(triggers_ht_node, struct lttng_trigger_ht_element, node); + cds_lfht_del(state->triggers_by_name_uid_ht, &trigger_ht_element->node_by_name_uid); cds_lfht_del(state->triggers_ht, triggers_ht_node); /* Release the ownership of the trigger. */ @@ -2412,17 +2787,20 @@ int handle_notification_thread_command( pthread_mutex_lock(&handle->cmd_queue.lock); cmd = cds_list_first_entry(&handle->cmd_queue.list, struct notification_thread_command, cmd_list_node); + cds_list_del(&cmd->cmd_list_node); + pthread_mutex_unlock(&handle->cmd_queue.lock); 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: @@ -2460,11 +2838,66 @@ 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; + + ret = handle_notification_thread_command_list_triggers( + handle, + state, + cmd->parameters.list_triggers.uid, + &triggers, + &cmd->reply_code); + cmd->reply.list_triggers.triggers = triggers; + ret = 0; + break; + } case NOTIFICATION_COMMAND_TYPE_QUIT: DBG("[notification-thread] Received quit command"); cmd->reply_code = LTTNG_OK; ret = 1; goto end; + case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE: + { + const enum client_transmission_status client_status = + cmd->parameters.client_communication_update + .status; + const notification_client_id client_id = + cmd->parameters.client_communication_update.id; + struct notification_client *client; + + rcu_read_lock(); + client = get_client_from_id(client_id, state); + + if (!client) { + /* + * Client error was probably already picked-up by the + * notification thread or it has disconnected + * gracefully while this command was queued. + */ + DBG("Failed to find notification client to update communication status, client id = %" PRIu64, + client_id); + ret = 0; + } else { + ret = client_handle_transmission_status( + client, client_status, state); + } + rcu_read_unlock(); + break; + } default: ERR("[notification-thread] Unknown internal command received"); goto error_unlock; @@ -2474,14 +2907,16 @@ int handle_notification_thread_command( goto error_unlock; } end: - cds_list_del(&cmd->cmd_list_node); - lttng_waiter_wake_up(&cmd->reply_waiter); - pthread_mutex_unlock(&handle->cmd_queue.lock); + if (cmd->is_async) { + free(cmd); + cmd = NULL; + } else { + lttng_waiter_wake_up(&cmd->reply_waiter); + } return ret; error_unlock: /* Wake-up and return a fatal error to the calling thread. */ lttng_waiter_wake_up(&cmd->reply_waiter); - pthread_mutex_unlock(&handle->cmd_queue.lock); cmd->reply_code = LTTNG_ERR_FATAL; error: /* Indicate a fatal error to the caller. */ @@ -2511,17 +2946,13 @@ end: return ret; } -/* Client lock must be acquired by caller. */ static int client_reset_inbound_state(struct notification_client *client) { int ret; - ASSERT_LOCKED(client->lock); - ret = lttng_dynamic_buffer_set_size( - &client->communication.inbound.buffer, 0); - assert(!ret); + lttng_payload_clear(&client->communication.inbound.payload); client->communication.inbound.bytes_to_receive = sizeof(struct lttng_notification_channel_message); @@ -2530,8 +2961,9 @@ int client_reset_inbound_state(struct notification_client *client) LTTNG_SOCK_SET_UID_CRED(&client->communication.inbound.creds, -1); LTTNG_SOCK_SET_GID_CRED(&client->communication.inbound.creds, -1); ret = lttng_dynamic_buffer_set_size( - &client->communication.inbound.buffer, + &client->communication.inbound.payload.buffer, client->communication.inbound.bytes_to_receive); + return ret; } @@ -2549,16 +2981,15 @@ int handle_notification_thread_client_connect( ret = -1; goto error; } + pthread_mutex_init(&client->lock, NULL); client->id = state->next_notification_client_id++; CDS_INIT_LIST_HEAD(&client->condition_list); - lttng_dynamic_buffer_init(&client->communication.inbound.buffer); - lttng_dynamic_buffer_init(&client->communication.outbound.buffer); + lttng_payload_init(&client->communication.inbound.payload); + lttng_payload_init(&client->communication.outbound.payload); client->communication.inbound.expect_creds = true; - pthread_mutex_lock(&client->lock); ret = client_reset_inbound_state(client); - pthread_mutex_unlock(&client->lock); if (ret) { ERR("[notification-thread] Failed to reset client communication's inbound state"); ret = 0; @@ -2608,13 +3039,16 @@ int handle_notification_thread_client_connect( rcu_read_unlock(); return ret; + error: notification_client_destroy(client, state); return ret; } -/* RCU read-lock must be held by the caller. */ -/* Client lock must be held by the caller */ +/* + * RCU read-lock must be held by the caller. + * Client lock must _not_ be held by the caller. + */ static int notification_thread_client_disconnect( struct notification_client *client, @@ -2624,16 +3058,18 @@ int notification_thread_client_disconnect( struct lttng_condition_list_element *condition_list_element, *tmp; /* Acquire the client lock to disable its communication atomically. */ + pthread_mutex_lock(&client->lock); client->communication.active = false; + cds_lfht_del(state->client_socket_ht, &client->client_socket_ht_node); + cds_lfht_del(state->client_id_ht, &client->client_id_ht_node); + pthread_mutex_unlock(&client->lock); + ret = lttng_poll_del(&state->events, client->socket); if (ret) { ERR("[notification-thread] Failed to remove client socket %d from poll set", client->socket); } - cds_lfht_del(state->client_socket_ht, &client->client_socket_ht_node); - cds_lfht_del(state->client_id_ht, &client->client_id_ht_node); - /* Release all conditions to which the client was subscribed. */ cds_list_for_each_entry_safe(condition_list_element, tmp, &client->condition_list, node) { @@ -2667,9 +3103,7 @@ int handle_notification_thread_client_disconnect( goto end; } - pthread_mutex_lock(&client->lock); ret = notification_thread_client_disconnect(client, state); - pthread_mutex_unlock(&client->lock); end: rcu_read_unlock(); return ret; @@ -2688,10 +3122,8 @@ int handle_notification_thread_client_disconnect_all( client_socket_ht_node) { int ret; - pthread_mutex_lock(&client->lock); ret = notification_thread_client_disconnect( client, state); - pthread_mutex_unlock(&client->lock); if (ret) { error_encoutered = true; } @@ -2720,80 +3152,186 @@ int handle_notification_thread_trigger_unregister_all( return error_occurred ? -1 : 0; } -/* Client lock must be acquired by caller. */ static -int client_flush_outgoing_queue(struct notification_client *client, +int client_handle_transmission_status( + struct notification_client *client, + enum client_transmission_status transmission_status, struct notification_thread_state *state) +{ + int ret = 0; + + switch (transmission_status) { + case CLIENT_TRANSMISSION_STATUS_COMPLETE: + ret = lttng_poll_mod(&state->events, client->socket, + CLIENT_POLL_MASK_IN); + if (ret) { + goto end; + } + + break; + case CLIENT_TRANSMISSION_STATUS_QUEUED: + /* + * We want to be notified whenever there is buffer space + * available to send the rest of the payload. + */ + ret = lttng_poll_mod(&state->events, client->socket, + CLIENT_POLL_MASK_IN_OUT); + if (ret) { + goto end; + } + break; + case CLIENT_TRANSMISSION_STATUS_FAIL: + ret = notification_thread_client_disconnect(client, state); + if (ret) { + goto end; + } + break; + case CLIENT_TRANSMISSION_STATUS_ERROR: + ret = -1; + goto end; + default: + abort(); + } +end: + return ret; +} + +/* Client lock must be acquired by caller. */ +static +enum client_transmission_status client_flush_outgoing_queue( + struct notification_client *client) { ssize_t ret; size_t to_send_count; + enum client_transmission_status status; + struct lttng_payload_view pv = lttng_payload_view_from_payload( + &client->communication.outbound.payload, 0, -1); + const int fds_to_send_count = + lttng_payload_view_get_fd_handle_count(&pv); ASSERT_LOCKED(client->lock); - assert(client->communication.outbound.buffer.size != 0); - to_send_count = client->communication.outbound.buffer.size; + if (!client->communication.active) { + status = CLIENT_TRANSMISSION_STATUS_FAIL; + goto end; + } + + if (pv.buffer.size == 0) { + /* + * If both data and fds are equal to zero, we are in an invalid + * state. + */ + assert(fds_to_send_count != 0); + goto send_fds; + } + + /* Send data. */ + to_send_count = pv.buffer.size; DBG("[notification-thread] Flushing client (socket fd = %i) outgoing queue", client->socket); ret = lttcomm_send_unix_sock_non_block(client->socket, - client->communication.outbound.buffer.data, + pv.buffer.data, to_send_count); if ((ret >= 0 && ret < to_send_count)) { DBG("[notification-thread] Client (socket fd = %i) outgoing queue could not be completely flushed", client->socket); to_send_count -= max(ret, 0); - memcpy(client->communication.outbound.buffer.data, - client->communication.outbound.buffer.data + - client->communication.outbound.buffer.size - to_send_count, + memmove(client->communication.outbound.payload.buffer.data, + pv.buffer.data + + pv.buffer.size - to_send_count, to_send_count); ret = lttng_dynamic_buffer_set_size( - &client->communication.outbound.buffer, + &client->communication.outbound.payload.buffer, to_send_count); if (ret) { goto error; } - /* - * We want to be notified whenever there is buffer space - * available to send the rest of the payload. - */ - ret = lttng_poll_mod(&state->events, client->socket, - CLIENT_POLL_MASK_IN_OUT); - if (ret) { - goto error; - } + status = CLIENT_TRANSMISSION_STATUS_QUEUED; + goto end; } else if (ret < 0) { - /* Generic error, disconnect the client. */ - ERR("[notification-thread] Failed to send flush outgoing queue, disconnecting client (socket fd = %i)", + /* Generic error, disable the client's communication. */ + ERR("[notification-thread] Failed to flush outgoing queue, disconnecting client (socket fd = %i)", client->socket); - ret = notification_thread_client_disconnect(client, state); - if (ret) { - goto error; - } + client->communication.active = false; + status = CLIENT_TRANSMISSION_STATUS_FAIL; + goto end; } else { - /* No error and flushed the queue completely. */ + /* + * No error and flushed the queue completely. + * + * The payload buffer size is used later to + * check if there is notifications queued. So albeit that the + * direct caller knows that the transmission is complete, we + * need to set the buffer size to zero. + */ ret = lttng_dynamic_buffer_set_size( - &client->communication.outbound.buffer, 0); - if (ret) { - goto error; - } - ret = lttng_poll_mod(&state->events, client->socket, - CLIENT_POLL_MASK_IN); + &client->communication.outbound.payload.buffer, 0); if (ret) { goto error; } + } + +send_fds: + /* No fds to send, transmission is complete. */ + if (fds_to_send_count == 0) { + status = CLIENT_TRANSMISSION_STATUS_COMPLETE; + goto end; + } + ret = lttcomm_send_payload_view_fds_unix_sock_non_block( + client->socket, &pv); + if (ret < 0) { + /* Generic error, disable the client's communication. */ + ERR("[notification-thread] Failed to flush outgoing fds queue, disconnecting client (socket fd = %i)", + client->socket); + client->communication.active = false; + status = CLIENT_TRANSMISSION_STATUS_FAIL; + goto end; + } else if (ret == 0) { + /* Nothing could be sent. */ + status = CLIENT_TRANSMISSION_STATUS_QUEUED; + } else { + /* Fd passing is an all or nothing kind of thing. */ + status = CLIENT_TRANSMISSION_STATUS_COMPLETE; + /* + * The payload _fd_array count is used later to + * check if there is notifications queued. So although the + * direct caller knows that the transmission is complete, we + * need to clear the _fd_array for the queuing check. + */ + lttng_dynamic_pointer_array_clear( + &client->communication.outbound.payload + ._fd_handles); + } + +end: + if (status == CLIENT_TRANSMISSION_STATUS_COMPLETE) { client->communication.outbound.queued_command_reply = false; client->communication.outbound.dropped_notification = false; + lttng_payload_clear(&client->communication.outbound.payload); } - return 0; + return status; error: - return -1; + return CLIENT_TRANSMISSION_STATUS_ERROR; } -/* Client lock must be acquired by caller. */ +static +bool client_has_outbound_data_left( + const struct notification_client *client) +{ + const struct lttng_payload_view pv = lttng_payload_view_from_payload( + &client->communication.outbound.payload, 0, -1); + const bool has_data = pv.buffer.size != 0; + const bool has_fds = lttng_payload_view_get_fd_handle_count(&pv); + + return has_data || has_fds; +} + +/* Client lock must _not_ be held by the caller. */ static int client_send_command_reply(struct notification_client *client, struct notification_thread_state *state, @@ -2808,37 +3346,43 @@ int client_send_command_reply(struct notification_client *client, .size = sizeof(reply), }; char buffer[sizeof(msg) + sizeof(reply)]; + enum client_transmission_status transmission_status; - ASSERT_LOCKED(client->lock); + memcpy(buffer, &msg, sizeof(msg)); + memcpy(buffer + sizeof(msg), &reply, sizeof(reply)); + DBG("[notification-thread] Send command reply (%i)", (int) status); + pthread_mutex_lock(&client->lock); if (client->communication.outbound.queued_command_reply) { /* Protocol error. */ - goto error; + goto error_unlock; } - memcpy(buffer, &msg, sizeof(msg)); - memcpy(buffer + sizeof(msg), &reply, sizeof(reply)); - DBG("[notification-thread] Send command reply (%i)", (int) status); - /* Enqueue buffer to outgoing queue and flush it. */ ret = lttng_dynamic_buffer_append( - &client->communication.outbound.buffer, + &client->communication.outbound.payload.buffer, buffer, sizeof(buffer)); if (ret) { - goto error; + goto error_unlock; } - ret = client_flush_outgoing_queue(client, state); - if (ret) { - goto error; - } + transmission_status = client_flush_outgoing_queue(client); - if (client->communication.outbound.buffer.size != 0) { + if (client_has_outbound_data_left(client)) { /* Queue could not be emptied. */ client->communication.outbound.queued_command_reply = true; } + pthread_mutex_unlock(&client->lock); + ret = client_handle_transmission_status( + client, transmission_status, state); + if (ret) { + goto error; + } + return 0; +error_unlock: + pthread_mutex_unlock(&client->lock); error: return -1; } @@ -2848,9 +3392,6 @@ int client_handle_message_unknown(struct notification_client *client, struct notification_thread_state *state) { int ret; - - pthread_mutex_lock(&client->lock); - /* * Receiving message header. The function will be called again * once the rest of the message as been received and can be @@ -2858,9 +3399,9 @@ int client_handle_message_unknown(struct notification_client *client, */ const struct lttng_notification_channel_message *msg; - assert(sizeof(*msg) == client->communication.inbound.buffer.size); + assert(sizeof(*msg) == client->communication.inbound.payload.buffer.size); msg = (const struct lttng_notification_channel_message *) - client->communication.inbound.buffer.data; + client->communication.inbound.payload.buffer.data; if (msg->size == 0 || msg->size > DEFAULT_MAX_NOTIFICATION_CLIENT_MESSAGE_PAYLOAD_SIZE) { @@ -2882,12 +3423,15 @@ int client_handle_message_unknown(struct notification_client *client, } client->communication.inbound.bytes_to_receive = msg->size; + client->communication.inbound.fds_to_receive = msg->fds; client->communication.inbound.msg_type = (enum lttng_notification_channel_message_type) msg->type; ret = lttng_dynamic_buffer_set_size( - &client->communication.inbound.buffer, msg->size); + &client->communication.inbound.payload.buffer, msg->size); + + /* msg is not valid anymore due to lttng_dynamic_buffer_set_size. */ + msg = NULL; end: - pthread_mutex_unlock(&client->lock); return ret; } @@ -2909,15 +3453,13 @@ int client_handle_message_handshake(struct notification_client *client, LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; char send_buffer[sizeof(msg_header) + sizeof(handshake_reply)]; - pthread_mutex_lock(&client->lock); - memcpy(send_buffer, &msg_header, sizeof(msg_header)); memcpy(send_buffer + sizeof(msg_header), &handshake_reply, sizeof(handshake_reply)); handshake_client = (struct lttng_notification_channel_command_handshake *) - client->communication.inbound.buffer + client->communication.inbound.payload.buffer .data; client->major = handshake_client->major; client->minor = handshake_client->minor; @@ -2940,37 +3482,38 @@ int client_handle_message_handshake(struct notification_client *client, status = LTTNG_NOTIFICATION_CHANNEL_STATUS_UNSUPPORTED_VERSION; } + pthread_mutex_lock(&client->lock); + /* Outgoing queue will be flushed when the command reply is sent. */ ret = lttng_dynamic_buffer_append( - &client->communication.outbound.buffer, send_buffer, + &client->communication.outbound.payload.buffer, send_buffer, sizeof(send_buffer)); if (ret) { ERR("[notification-thread] Failed to send protocol version to notification channel client"); - goto end; + goto end_unlock; } client->validated = true; client->communication.active = true; + pthread_mutex_unlock(&client->lock); - ret = client_flush_outgoing_queue(client, state); + /* Set reception state to receive the next message header. */ + ret = client_reset_inbound_state(client); if (ret) { + ERR("[notification-thread] Failed to reset client communication's inbound state"); goto end; } + /* Flushes the outgoing queue. */ ret = client_send_command_reply(client, state, status); if (ret) { ERR("[notification-thread] Failed to send reply to notification channel client"); goto end; } - /* Set reception state to receive the next message header. */ - ret = client_reset_inbound_state(client); - if (ret) { - ERR("[notification-thread] Failed to reset client communication's inbound state"); - goto end; - } - -end: + goto end; +end_unlock: pthread_mutex_unlock(&client->lock); +end: return ret; } @@ -2985,15 +3528,17 @@ int client_handle_message_subscription( enum lttng_notification_channel_status status = LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; struct lttng_payload_view condition_view = - lttng_payload_view_from_dynamic_buffer( - &client->communication.inbound.buffer, + lttng_payload_view_from_payload( + &client->communication.inbound.payload, 0, -1); size_t expected_condition_size; - pthread_mutex_lock(&client->lock); - expected_condition_size = client->communication.inbound.buffer.size; - pthread_mutex_unlock(&client->lock); - + /* + * No need to lock client to sample the inbound state as the only + * other thread accessing clients (action executor) only uses the + * outbound state. + */ + expected_condition_size = client->communication.inbound.payload.buffer.size; ret = lttng_condition_create_from_payload(&condition_view, &condition); if (ret != expected_condition_size) { ERR("[notification-thread] Malformed condition received from client"); @@ -3007,26 +3552,24 @@ int client_handle_message_subscription( ret = notification_thread_client_unsubscribe( client, condition, state, &status); } - if (ret) { - goto end; - } - pthread_mutex_lock(&client->lock); - ret = client_send_command_reply(client, state, status); if (ret) { - ERR("[notification-thread] Failed to send reply to notification channel client"); - goto end_unlock; + goto end; } /* Set reception state to receive the next message header. */ ret = client_reset_inbound_state(client); if (ret) { ERR("[notification-thread] Failed to reset client communication's inbound state"); - goto end_unlock; + goto end; + } + + ret = client_send_command_reply(client, state, status); + if (ret) { + ERR("[notification-thread] Failed to send reply to notification channel client"); + goto end; } -end_unlock: - pthread_mutex_unlock(&client->lock); end: return ret; } @@ -3080,8 +3623,8 @@ int handle_notification_thread_client_in( struct notification_client *client; ssize_t recv_ret; size_t offset; - bool message_is_complete = false; + rcu_read_lock(); client = get_client_from_socket(socket, state); if (!client) { /* Internal error, abort. */ @@ -3089,12 +3632,11 @@ int handle_notification_thread_client_in( goto end; } - pthread_mutex_lock(&client->lock); - offset = client->communication.inbound.buffer.size - + offset = client->communication.inbound.payload.buffer.size - client->communication.inbound.bytes_to_receive; if (client->communication.inbound.expect_creds) { recv_ret = lttcomm_recv_creds_unix_sock(socket, - client->communication.inbound.buffer.data + offset, + client->communication.inbound.payload.buffer.data + offset, client->communication.inbound.bytes_to_receive, &client->communication.inbound.creds); if (recv_ret > 0) { @@ -3103,36 +3645,69 @@ int handle_notification_thread_client_in( } } else { recv_ret = lttcomm_recv_unix_sock_non_block(socket, - client->communication.inbound.buffer.data + offset, + client->communication.inbound.payload.buffer.data + offset, client->communication.inbound.bytes_to_receive); } if (recv_ret >= 0) { client->communication.inbound.bytes_to_receive -= recv_ret; - message_is_complete = client->communication.inbound - .bytes_to_receive == 0; - } - pthread_mutex_unlock(&client->lock); - if (recv_ret < 0) { + } else { goto error_disconnect_client; } - if (message_is_complete) { - ret = client_dispatch_message(client, state); - if (ret) { + if (client->communication.inbound.bytes_to_receive != 0) { + /* Message incomplete wait for more data. */ + ret = 0; + goto end; + } + + assert(client->communication.inbound.bytes_to_receive == 0); + + /* Receive fds. */ + if (client->communication.inbound.fds_to_receive != 0) { + ret = lttcomm_recv_payload_fds_unix_sock_non_block( + client->socket, + client->communication.inbound.fds_to_receive, + &client->communication.inbound.payload); + if (ret > 0) { /* - * Only returns an error if this client must be - * disconnected. + * Fds received. non blocking fds passing is all + * or nothing. */ + ssize_t expected_size; + + expected_size = sizeof(int) * + client->communication.inbound + .fds_to_receive; + assert(ret == expected_size); + client->communication.inbound.fds_to_receive = 0; + } else if (ret == 0) { + /* Received nothing. */ + ret = 0; + goto end; + } else { goto error_disconnect_client; } } + + /* At this point the message is complete.*/ + assert(client->communication.inbound.bytes_to_receive == 0 && + client->communication.inbound.fds_to_receive == 0); + ret = client_dispatch_message(client, state); + if (ret) { + /* + * Only returns an error if this client must be + * disconnected. + */ + goto error_disconnect_client; + } + end: + rcu_read_unlock(); return ret; + error_disconnect_client: - pthread_mutex_lock(&client->lock); ret = notification_thread_client_disconnect(client, state); - pthread_mutex_unlock(&client->lock); - return ret; + goto end; } /* Client ready to receive outgoing data. */ @@ -3141,7 +3716,9 @@ int handle_notification_thread_client_out( { int ret; struct notification_client *client; + enum client_transmission_status transmission_status; + rcu_read_lock(); client = get_client_from_socket(socket, state); if (!client) { /* Internal error, abort. */ @@ -3150,12 +3727,16 @@ int handle_notification_thread_client_out( } pthread_mutex_lock(&client->lock); - ret = client_flush_outgoing_queue(client, state); + transmission_status = client_flush_outgoing_queue(client); pthread_mutex_unlock(&client->lock); + + ret = client_handle_transmission_status( + client, transmission_status, state); if (ret) { goto end; } end: + rcu_read_unlock(); return ret; } @@ -3322,22 +3903,66 @@ end: } static -int client_enqueue_dropped_notification(struct notification_client *client) +int client_notification_overflow(struct notification_client *client) { - int ret; - struct lttng_notification_channel_message msg = { + int ret = 0; + const struct lttng_notification_channel_message msg = { .type = (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED, - .size = 0, }; ASSERT_LOCKED(client->lock); + DBG("Dropping notification addressed to client (socket fd = %i)", + client->socket); + if (client->communication.outbound.dropped_notification) { + /* + * The client already has a "notification dropped" message + * in its outgoing queue. Nothing to do since all + * of those messages are coalesced. + */ + goto end; + } + + client->communication.outbound.dropped_notification = true; ret = lttng_dynamic_buffer_append( - &client->communication.outbound.buffer, &msg, + &client->communication.outbound.payload.buffer, &msg, sizeof(msg)); + if (ret) { + PERROR("Failed to enqueue \"dropped notification\" message in client's (socket fd = %i) outgoing queue", + client->socket); + } +end: return ret; } +static int client_handle_transmission_status_wrapper( + struct notification_client *client, + enum client_transmission_status status, + void *user_data) +{ + return client_handle_transmission_status(client, status, + (struct notification_thread_state *) user_data); +} + +static +int send_evaluation_to_clients(const struct lttng_trigger *trigger, + const struct lttng_evaluation *evaluation, + struct notification_client_list* client_list, + struct notification_thread_state *state, + uid_t object_uid, gid_t object_gid) +{ + const struct lttng_credentials creds = { + .uid = LTTNG_OPTIONAL_INIT_VALUE(object_uid), + .gid = LTTNG_OPTIONAL_INIT_VALUE(object_gid), + }; + + return notification_client_list_send_evaluation(client_list, + lttng_trigger_get_const_condition(trigger), evaluation, + lttng_trigger_get_credentials(trigger), + &creds, + client_handle_transmission_status_wrapper, state); +} + /* * Permission checks relative to notification channel clients are performed * here. Notice how object, client, and trigger credentials are involved in @@ -3371,24 +3996,26 @@ int client_enqueue_dropped_notification(struct notification_client *client) * interference from external users (those could, for instance, unregister * their triggers). */ -static -int send_evaluation_to_clients(const struct lttng_trigger *trigger, +LTTNG_HIDDEN +int notification_client_list_send_evaluation( + struct notification_client_list *client_list, + const struct lttng_condition *condition, const struct lttng_evaluation *evaluation, - struct notification_client_list* client_list, - struct notification_thread_state *state, - uid_t object_uid, gid_t object_gid) + const struct lttng_credentials *trigger_creds, + const struct lttng_credentials *source_object_creds, + report_client_transmission_result_cb client_report, + void *user_data) { int ret = 0; struct lttng_payload msg_payload; struct notification_client_list_element *client_list_element, *tmp; const struct lttng_notification notification = { - .condition = (struct lttng_condition *) lttng_trigger_get_const_condition(trigger), + .condition = (struct lttng_condition *) condition, .evaluation = (struct lttng_evaluation *) evaluation, }; struct lttng_notification_channel_message msg_header = { .type = (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION, }; - const struct lttng_credentials *trigger_creds = lttng_trigger_get_credentials(trigger); lttng_payload_init(&msg_payload); @@ -3410,29 +4037,56 @@ int send_evaluation_to_clients(const struct lttng_trigger *trigger, ->size = (uint32_t)( msg_payload.buffer.size - sizeof(msg_header)); + /* Update the payload number of fds. */ + { + const struct lttng_payload_view pv = lttng_payload_view_from_payload( + &msg_payload, 0, -1); + + ((struct lttng_notification_channel_message *) + msg_payload.buffer.data)->fds = (uint32_t) + lttng_payload_view_get_fd_handle_count(&pv); + } + 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; ret = 0; pthread_mutex_lock(&client->lock); - if (client->uid != object_uid && client->gid != object_gid && - client->uid != 0) { - /* Client is not allowed to monitor this channel. */ - DBG("[notification-thread] Skipping client at it does not have the object permission to receive notification for this trigger"); - goto unlock_client; + if (!client->communication.active) { + /* + * Skip inactive client (protocol error or + * disconnecting). + */ + DBG("Skipping client at it is marked as inactive"); + goto skip_client; + } + + if (source_object_creds) { + if (client->uid != lttng_credentials_get_uid(source_object_creds) && + client->gid != lttng_credentials_get_gid(source_object_creds) && + client->uid != 0) { + /* + * Client is not allowed to monitor this + * object. + */ + DBG("[notification-thread] Skipping client at it does not have the object permission to receive notification for this trigger"); + goto skip_client; + } } - if (client->uid != trigger_creds->uid && client->gid != trigger_creds->gid) { + if (client->uid != lttng_credentials_get_uid(trigger_creds) && client->gid != lttng_credentials_get_gid(trigger_creds)) { DBG("[notification-thread] Skipping client at it does not have the permission to receive notification for this trigger"); - goto unlock_client; + goto skip_client; } DBG("[notification-thread] Sending notification to client (fd = %i, %zu bytes)", client->socket, msg_payload.buffer.size); - if (client->communication.outbound.buffer.size) { + + if (client_has_outbound_data_left(client)) { /* * Outgoing data is already buffered for this client; * drop the notification and enqueue a "dropped @@ -3440,33 +4094,33 @@ int send_evaluation_to_clients(const struct lttng_trigger *trigger, * notification since the socket spilled-over to the * queue. */ - DBG("[notification-thread] Dropping notification addressed to client (socket fd = %i)", - client->socket); - if (!client->communication.outbound.dropped_notification) { - client->communication.outbound.dropped_notification = true; - ret = client_enqueue_dropped_notification( - client); - if (ret) { - goto unlock_client; - } + ret = client_notification_overflow(client); + if (ret) { + /* Fatal error. */ + goto skip_client; } - goto unlock_client; } - ret = lttng_dynamic_buffer_append_buffer( - &client->communication.outbound.buffer, - &msg_payload.buffer); + ret = lttng_payload_copy(&msg_payload, &client->communication.outbound.payload); if (ret) { - goto unlock_client; + /* Fatal error. */ + goto skip_client; } - ret = client_flush_outgoing_queue(client, state); + transmission_status = client_flush_outgoing_queue(client); + pthread_mutex_unlock(&client->lock); + ret = client_report(client, transmission_status, user_data); if (ret) { - goto unlock_client; + /* Fatal error. */ + goto end_unlock_list; } -unlock_client: + + continue; + +skip_client: pthread_mutex_unlock(&client->lock); if (ret) { + /* Fatal error. */ goto end_unlock_list; } } @@ -3493,6 +4147,7 @@ int handle_notification_thread_channel_sample( bool previous_sample_available = false; struct channel_state_sample previous_sample, latest_sample; uint64_t previous_session_consumed_total, latest_session_consumed_total; + struct lttng_credentials channel_creds; /* * The monitoring pipe only holds messages smaller than PIPE_BUF, @@ -3611,41 +4266,31 @@ int handle_notification_thread_channel_sample( goto end_unlock; } + channel_creds = (typeof(channel_creds)) { + .uid = LTTNG_OPTIONAL_INIT_VALUE(channel_info->session_info->uid), + .gid = LTTNG_OPTIONAL_INIT_VALUE(channel_info->session_info->gid), + }; + trigger_list = caa_container_of(node, struct lttng_channel_trigger_list, channel_triggers_ht_node); cds_list_for_each_entry(trigger_list_element, &trigger_list->list, node) { const struct lttng_condition *condition; - const struct lttng_action *action; - const struct lttng_trigger *trigger; + struct lttng_trigger *trigger; struct notification_client_list *client_list = NULL; struct lttng_evaluation *evaluation = NULL; - bool client_list_is_empty; + enum action_executor_status executor_status; ret = 0; trigger = trigger_list_element->trigger; condition = lttng_trigger_get_const_condition(trigger); assert(condition); - action = lttng_trigger_get_const_action(trigger); - - /* Notify actions are the only type currently supported. */ - assert(lttng_action_get_type_const(action) == - LTTNG_ACTION_TYPE_NOTIFY); /* * Check if any client is subscribed to the result of this * evaluation. */ client_list = get_client_list_from_condition(state, condition); - assert(client_list); - client_list_is_empty = cds_list_empty(&client_list->list); - if (client_list_is_empty) { - /* - * No clients interested in the evaluation's result, - * skip it. - */ - goto put_list; - } ret = evaluate_buffer_condition(condition, &evaluation, state, previous_sample_available ? &previous_sample : NULL, @@ -3661,12 +4306,46 @@ int handle_notification_thread_channel_sample( goto put_list; } - /* Dispatch evaluation result to all clients. */ - ret = send_evaluation_to_clients(trigger_list_element->trigger, - evaluation, client_list, state, - channel_info->session_info->uid, - channel_info->session_info->gid); - lttng_evaluation_destroy(evaluation); + if (!lttng_trigger_should_fire(trigger)) { + goto put_list; + } + + lttng_trigger_fire(trigger); + + /* + * Ownership of `evaluation` transferred to the action executor + * no matter the result. + */ + executor_status = action_executor_enqueue(state->executor, + trigger, evaluation, &channel_creds, + client_list); + evaluation = NULL; + switch (executor_status) { + case ACTION_EXECUTOR_STATUS_OK: + break; + case ACTION_EXECUTOR_STATUS_ERROR: + case ACTION_EXECUTOR_STATUS_INVALID: + /* + * TODO Add trigger identification (name/id) when + * it is added to the API. + */ + ERR("Fatal error occurred while enqueuing action associated with buffer-condition trigger"); + ret = -1; + goto put_list; + case ACTION_EXECUTOR_STATUS_OVERFLOW: + /* + * TODO Add trigger identification (name/id) when + * it is added to the API. + * + * Not a fatal error. + */ + WARN("No space left when enqueuing action associated with buffer-condition trigger"); + ret = 0; + goto put_list; + default: + abort(); + } + put_list: notification_client_list_put(client_list); if (caa_unlikely(ret)) {