X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fnotification-thread-events.c;h=ccd285a8103d6a344bcb3344abbd982f079a0c13;hp=de654a4ee8bade30772e1fc73af04174179a8638;hb=98dfca790cb8fcd3bac11a4f4f58c933f99d2a1a;hpb=f2b3ef9f7d7adf6cc0678cd5933b638f5a9e75a6 diff --git a/src/bin/lttng-sessiond/notification-thread-events.c b/src/bin/lttng-sessiond/notification-thread-events.c index de654a4ee..ccd285a81 100644 --- a/src/bin/lttng-sessiond/notification-thread-events.c +++ b/src/bin/lttng-sessiond/notification-thread-events.c @@ -21,12 +21,18 @@ #include #include #include +#include +#include #include #include #include #include #include +#include +#include #include +#include +#include #include #include @@ -34,6 +40,7 @@ #include #include +#include "condition-internal.h" #include "notification-thread.h" #include "notification-thread-events.h" #include "notification-thread-commands.h" @@ -43,6 +50,9 @@ #define CLIENT_POLL_MASK_IN (LPOLLIN | LPOLLERR | LPOLLHUP | LPOLLRDHUP) #define CLIENT_POLL_MASK_IN_OUT (CLIENT_POLL_MASK_IN | LPOLLOUT) +/* The tracers currently limit the capture size to PIPE_BUF (4kb on linux). */ +#define MAX_CAPTURE_SIZE (PIPE_BUF) + enum lttng_object_type { LTTNG_OBJECT_TYPE_UNKNOWN, LTTNG_OBJECT_TYPE_NONE, @@ -110,6 +120,7 @@ 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; }; @@ -187,6 +198,14 @@ int client_handle_transmission_status( enum client_transmission_status transmission_status, struct notification_thread_state *state); +static +int handle_one_event_notifier_notification( + struct notification_thread_state *state, + int pipe, enum lttng_domain_type domain); + +static +void free_lttng_trigger_ht_element_rcu(struct rcu_head *node); + static int match_client_socket(struct cds_lfht_node *node, const void *key) { @@ -261,18 +280,26 @@ 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 @@ -302,102 +329,100 @@ int match_session(struct cds_lfht_node *node, const void *key) } static -unsigned long lttng_condition_buffer_usage_hash( - const struct lttng_condition *_condition) +const char *notification_command_type_str( + enum notification_thread_command_type type) { - 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); + 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(); } - return hash; } +/* + * Match trigger based on name and credentials only. + * Name duplication is NOT allowed for the same uid. + */ static -unsigned long lttng_condition_session_consumed_size_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 = - (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); + 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; } - 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; + /* Compare the owners' UIDs. */ + key_creds = lttng_trigger_get_credentials(trigger_key); + node_creds = lttng_trigger_get_credentials(trigger_ht_element->trigger); - 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; + match = lttng_credentials_is_equal_uid(key_creds, node_creds); + +end: + return match; } /* - * 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. + * Hash trigger based on name and credentials only. */ static -unsigned long lttng_condition_hash(const struct lttng_condition *condition) +unsigned long hash_trigger_by_name_uid(const struct lttng_trigger *trigger) { - 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(); + unsigned long hash = 0; + const struct lttng_credentials *trigger_creds; + const char *trigger_name; + enum lttng_trigger_status status; + + status = lttng_trigger_get_name(trigger, &trigger_name); + if (status == LTTNG_TRIGGER_STATUS_OK) { + hash = hash_key_str(trigger_name, lttng_ht_seed); } + + trigger_creds = lttng_trigger_get_credentials(trigger); + hash ^= hash_key_ulong((void *) (unsigned long) LTTNG_OPTIONAL_GET(trigger_creds->uid), + lttng_ht_seed); + + return hash; } static @@ -442,6 +467,8 @@ 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; } @@ -952,6 +979,7 @@ 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: @@ -1184,8 +1212,8 @@ 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); } @@ -1623,7 +1651,7 @@ 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); @@ -1724,7 +1752,7 @@ 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(); @@ -1807,8 +1835,8 @@ int handle_notification_thread_command_session_rotation( struct lttng_trigger_list_element *trigger_list_element; struct session_info *session_info; const struct lttng_credentials session_creds = { - .uid = session_uid, - .gid = session_gid, + .uid = LTTNG_OPTIONAL_INIT_VALUE(session_uid), + .gid = LTTNG_OPTIONAL_INIT_VALUE(session_gid), }; rcu_read_lock(); @@ -1918,25 +1946,269 @@ 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 drain_event_notifier_notification_pipe( + struct notification_thread_state *state, + int pipe, enum lttng_domain_type domain) +{ + struct lttng_poll_event events = {0}; + int ret; + + ret = lttng_poll_create(&events, 1, LTTNG_CLOEXEC); + if (ret < 0) { + ERR("[notification-thread] Error creating lttng_poll_event"); + goto end; + } + + ret = lttng_poll_add(&events, pipe, LPOLLIN); + if (ret < 0) { + ERR("[notification-thread] Error adding fd event notifier notification pipe to lttng_poll_event: fd = %d", + pipe); + goto end; + } + + while (true) { + /* + * Continue to consume notifications as long as there are new + * ones coming in. The tracer has been asked to stop producing + * them. + * + * LPOLLIN is explicitly checked since LPOLLHUP is implicitly + * monitored (on Linux, at least) and will be returned when + * the pipe is closed but empty. + */ + ret = lttng_poll_wait_interruptible(&events, 0); + if (ret == 0 || (LTTNG_POLL_GETEV(&events, 0) & LPOLLIN) == 0) { + /* No more notification to be read on this pipe. */ + ret = 0; + goto end; + } else if (ret < 0) { + PERROR("Failed on lttng_poll_wait_interruptible() call"); + ret = -1; + goto end; + } + + ret = handle_one_event_notifier_notification(state, pipe, domain); + if (ret) { + ERR("[notification-thread] Error consuming an event notifier notification from pipe: fd = %d", + pipe); + } + } +end: + lttng_poll_clean(&events); + return ret; +} + +static +int handle_notification_thread_command_remove_tracer_event_source( + struct notification_thread_state *state, + 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; + + ret = drain_event_notifier_notification_pipe(state, tracer_event_source_fd, + source_element->domain); + if (ret) { + ERR("[notification-thread] Error draining event notifier notification: tracer_event_source_fd = %d, domain = %s", + tracer_event_source_fd, + lttng_domain_type_str(source_element->domain)); + cmd_result = LTTNG_ERR_FATAL; + goto end; + } + + /* + * The drain_event_notifier_notification_pipe() call might have read + * data from an fd that we received in event in the latest _poll_wait() + * call. Make sure the thread call poll_wait() again to ensure we have + * a clean state. + */ + state->restart_poll = true; + +end: + free(source_element); + *_cmd_result = cmd_result; + 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; } @@ -1944,15 +2216,43 @@ 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. */ @@ -2058,7 +2358,7 @@ bool is_trigger_action_notify(const struct lttng_trigger *trigger) enum lttng_action_type action_type; assert(action); - action_type = lttng_action_get_type_const(action); + action_type = lttng_action_get_type(action); if (action_type == LTTNG_ACTION_TYPE_NOTIFY) { is_notify = true; goto end; @@ -2074,7 +2374,7 @@ bool is_trigger_action_notify(const struct lttng_trigger *trigger) lttng_action_group_get_at_index( action, i); - action_type = lttng_action_get_type_const(inner_action); + action_type = lttng_action_get_type(inner_action); if (action_type == LTTNG_ACTION_TYPE_NOTIFY) { is_notify = true; goto end; @@ -2085,6 +2385,50 @@ 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. * @@ -2112,27 +2456,49 @@ 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; 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)); @@ -2143,12 +2509,13 @@ 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. */ @@ -2156,14 +2523,63 @@ int handle_notification_thread_command_register_trigger( goto error_free_ht_element; } - /* - * Ownership of the trigger and of its wrapper was transfered to - * the triggers_ht. - */ - trigger_ht_element = NULL; - free_trigger = false; + 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. Same for token ht element if necessary. + */ + trigger_tokens_ht_element = NULL; + trigger_ht_element = NULL; + free_trigger = false; + + /* * The rest only applies to triggers that have a "notify" action. * It is not skipped as this is the only action type currently * supported. @@ -2260,21 +2676,25 @@ int handle_notification_thread_command_register_trigger( switch (get_condition_binding_object(condition)) { case LTTNG_OBJECT_TYPE_SESSION: ret = evaluate_session_condition_for_client(condition, state, - &evaluation, &object_creds.uid, - &object_creds.gid); + &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_creds.uid, - &object_creds.gid); + &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; - goto error_put_client_list; + break; case LTTNG_OBJECT_TYPE_UNKNOWN: default: ret = -1; - goto error_put_client_list; + break; } if (ret) { @@ -2287,7 +2707,7 @@ int handle_notification_thread_command_register_trigger( if (!evaluation) { /* Evaluation yielded nothing. Normal exit. */ ret = 0; - goto error_put_client_list; + goto end; } /* @@ -2318,18 +2738,27 @@ int handle_notification_thread_command_register_trigger( */ WARN("No space left when enqueuing action associated to newly registered trigger"); ret = 0; - goto error_put_client_list; + 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); @@ -2345,10 +2774,17 @@ 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; @@ -2356,7 +2792,7 @@ 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; @@ -2364,8 +2800,8 @@ 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) { @@ -2382,13 +2818,7 @@ 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; } @@ -2399,21 +2829,46 @@ 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. */ @@ -2448,21 +2903,22 @@ 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, @@ -2475,7 +2931,6 @@ 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, @@ -2483,9 +2938,6 @@ 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, @@ -2496,8 +2948,34 @@ 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; @@ -2523,10 +3001,8 @@ int handle_notification_thread_command( client_id); ret = 0; } else { - pthread_mutex_lock(&client->lock); ret = client_handle_transmission_status( client, client_status, state); - pthread_mutex_unlock(&client->lock); } rcu_read_unlock(); break; @@ -2579,17 +3055,13 @@ 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); @@ -2598,8 +3070,9 @@ 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; } @@ -2617,16 +3090,15 @@ 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; @@ -2676,13 +3148,16 @@ 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, @@ -2692,16 +3167,18 @@ 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) { @@ -2735,9 +3212,7 @@ 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; @@ -2756,10 +3231,8 @@ 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; } @@ -2804,8 +3277,6 @@ int client_handle_transmission_status( goto end; } - client->communication.outbound.queued_command_reply = false; - client->communication.outbound.dropped_notification = false; break; case CLIENT_TRANSMISSION_STATUS_QUEUED: /* @@ -2842,6 +3313,10 @@ enum client_transmission_status client_flush_outgoing_queue( 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); @@ -2850,51 +3325,122 @@ enum client_transmission_status client_flush_outgoing_queue( goto end; } - assert(client->communication.outbound.buffer.size != 0); - to_send_count = client->communication.outbound.buffer.size; + 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; } + status = CLIENT_TRANSMISSION_STATUS_QUEUED; + goto end; } else if (ret < 0) { - /* Generic error, disconnect the client. */ + /* Generic error, disable the client's communication. */ ERR("[notification-thread] Failed to flush outgoing queue, disconnecting client (socket fd = %i)", client->socket); + 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); + &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 status; error: 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, @@ -2911,38 +3457,41 @@ int client_send_command_reply(struct notification_client *client, 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; } transmission_status = client_flush_outgoing_queue(client); + + 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; } - if (client->communication.outbound.buffer.size != 0) { - /* Queue could not be emptied. */ - client->communication.outbound.queued_command_reply = true; - } - return 0; +error_unlock: + pthread_mutex_unlock(&client->lock); error: return -1; } @@ -2952,9 +3501,6 @@ 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 @@ -2962,9 +3508,9 @@ 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) { @@ -2986,12 +3532,15 @@ 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; } @@ -3012,9 +3561,6 @@ int client_handle_message_handshake(struct notification_client *client, enum lttng_notification_channel_status status = LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; char send_buffer[sizeof(msg_header) + sizeof(handshake_reply)]; - enum client_transmission_status transmission_status; - - pthread_mutex_lock(&client->lock); memcpy(send_buffer, &msg_header, sizeof(msg_header)); memcpy(send_buffer + sizeof(msg_header), &handshake_reply, @@ -3022,7 +3568,7 @@ int client_handle_message_handshake(struct notification_client *client, 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; @@ -3045,39 +3591,38 @@ 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); - transmission_status = client_flush_outgoing_queue(client); - ret = client_handle_transmission_status( - client, transmission_status, 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; } @@ -3092,15 +3637,17 @@ 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"); @@ -3114,26 +3661,24 @@ 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; } @@ -3187,8 +3732,8 @@ 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. */ @@ -3196,12 +3741,11 @@ 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) { @@ -3210,36 +3754,69 @@ 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. */ @@ -3250,6 +3827,7 @@ int handle_notification_thread_client_out( 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. */ @@ -3259,13 +3837,15 @@ int handle_notification_thread_client_out( pthread_mutex_lock(&client->lock); transmission_status = client_flush_outgoing_queue(client); + pthread_mutex_unlock(&client->lock); + ret = client_handle_transmission_status( client, transmission_status, state); - pthread_mutex_unlock(&client->lock); if (ret) { goto end; } end: + rcu_read_unlock(); return ret; } @@ -3454,7 +4034,7 @@ int client_notification_overflow(struct notification_client *client) 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", @@ -3480,11 +4060,15 @@ int send_evaluation_to_clients(const struct lttng_trigger *trigger, 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), - &(struct lttng_credentials){ - .uid = object_uid, .gid = object_gid}, + &creds, client_handle_transmission_status_wrapper, state); } @@ -3562,6 +4146,16 @@ int notification_client_list_send_evaluation( ->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) { @@ -3571,27 +4165,37 @@ int notification_client_list_send_evaluation( ret = 0; pthread_mutex_lock(&client->lock); + 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 != source_object_creds->uid && - client->gid != source_object_creds->gid && + 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 unlock_client; + 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 @@ -3601,25 +4205,31 @@ int notification_client_list_send_evaluation( */ ret = client_notification_overflow(client); if (ret) { - goto unlock_client; + /* Fatal error. */ + goto skip_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; } 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; } } @@ -3632,6 +4242,286 @@ end: return ret; } +static +struct lttng_event_notifier_notification *recv_one_event_notifier_notification( + int notification_pipe_read_fd, enum lttng_domain_type domain) +{ + int ret; + uint64_t token; + struct lttng_event_notifier_notification *notification = NULL; + char *capture_buffer = NULL; + size_t capture_buffer_size; + void *reception_buffer; + size_t reception_size; + + struct lttng_ust_abi_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; + capture_buffer_size = ust_notification.capture_buf_size; + break; + case LTTNG_DOMAIN_KERNEL: + token = kernel_notification.token; + capture_buffer_size = 0; + break; + default: + abort(); + } + + if (capture_buffer_size == 0) { + capture_buffer = NULL; + goto skip_capture; + } + + if (capture_buffer_size > MAX_CAPTURE_SIZE) { + ERR("[notification-thread] Event notifier has a capture payload size which exceeds the maximum allowed size: capture_payload_size = %zu bytes, max allowed size = %d bytes", + capture_buffer_size, MAX_CAPTURE_SIZE); + goto end; + } + + capture_buffer = zmalloc(capture_buffer_size); + if (!capture_buffer) { + ERR("[notification-thread] Failed to allocate capture buffer"); + goto end; + } + + /* Fetch additional payload (capture). */ + ret = lttng_read(notification_pipe_read_fd, capture_buffer, capture_buffer_size); + if (ret != capture_buffer_size) { + ERR("[notification-thread] Failed to read from event source pipe (fd = %i)", + notification_pipe_read_fd); + goto end; + } + +skip_capture: + notification = lttng_event_notifier_notification_create(token, domain, + capture_buffer, capture_buffer_size); + if (notification == NULL) { + goto end; + } + + /* + * Ownership transfered to the lttng_event_notifier_notification object. + */ + capture_buffer = NULL; + +end: + free(capture_buffer); + return notification; +} + +static +int dispatch_one_event_notifier_notification(struct notification_thread_state *state, + struct lttng_event_notifier_notification *notification) +{ + struct cds_lfht_node *node; + struct cds_lfht_iter iter; + struct notification_trigger_tokens_ht_element *element; + enum lttng_trigger_status trigger_status; + struct lttng_evaluation *evaluation = NULL; + enum action_executor_status executor_status; + struct notification_client_list *client_list = NULL; + const char *trigger_name; + int ret; + unsigned int capture_count = 0; + + /* 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); + + if (lttng_condition_event_rule_get_capture_descriptor_count( + lttng_trigger_get_const_condition(element->trigger), + &capture_count) != LTTNG_CONDITION_STATUS_OK) { + ERR("Failed to get capture count"); + ret = -1; + goto end; + } + + if (!notification->capture_buffer && capture_count != 0) { + ERR("Expected capture but capture buffer is null"); + ret = -1; + goto end; + } + + evaluation = lttng_evaluation_event_rule_create( + container_of(lttng_trigger_get_const_condition( + element->trigger), + struct lttng_condition_event_rule, + parent), + trigger_name, + notification->capture_buffer, + notification->capture_buf_size, false); + + 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_INVALID: + case ACTION_EXECUTOR_STATUS_ERROR: + /* Fatal error, shut down everything. */ + ERR("Fatal error encoutered while enqueuing action to the action executor"); + ret = -1; + goto end_unlock; + default: + /* Unhandled error. */ + abort(); + } + +end_unlock: + notification_client_list_put(client_list); + rcu_read_unlock(); +end: + return ret; +} + +static +int handle_one_event_notifier_notification( + struct notification_thread_state *state, + int pipe, enum lttng_domain_type domain) +{ + int ret = 0; + struct lttng_event_notifier_notification *notification = NULL; + + notification = recv_one_event_notifier_notification(pipe, domain); + if (notification == NULL) { + /* Reception failed, don't consider it fatal. */ + ERR("[notification-thread] Error receiving an event notifier notification from tracer: fd = %i, domain = %s", + pipe, lttng_domain_type_str(domain)); + goto end; + } + + ret = dispatch_one_event_notifier_notification(state, notification); + if (ret) { + ERR("[notification-thread] Error dispatching an event notifier notification from tracer: fd = %i, domain = %s", + pipe, lttng_domain_type_str(domain)); + goto end; + } + +end: + lttng_event_notifier_notification_destroy(notification); + return ret; +} + +int handle_notification_thread_event_notification(struct notification_thread_state *state, + int pipe, enum lttng_domain_type domain) +{ + return handle_one_event_notifier_notification(state, pipe, domain); +} + int handle_notification_thread_channel_sample( struct notification_thread_state *state, int pipe, enum lttng_domain_type domain) @@ -3685,8 +4575,7 @@ 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, @@ -3766,8 +4655,8 @@ int handle_notification_thread_channel_sample( } channel_creds = (typeof(channel_creds)) { - .uid = channel_info->session_info->uid, - .gid = channel_info->session_info->gid, + .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, @@ -3805,6 +4694,12 @@ int handle_notification_thread_channel_sample( goto put_list; } + 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.