X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fnotification-thread.c;h=62d47ee54182cfc3da2a27d3dbf4ba37638a67f4;hp=c652b6ee8417563c7c45cfec188770af6d2ce94c;hb=8abe313a6c4f251063e4b72ddd47ce8107384d71;hpb=4149ace8fa7c7a8da39272f03923df46039c5ff6 diff --git a/src/bin/lttng-sessiond/notification-thread.c b/src/bin/lttng-sessiond/notification-thread.c index c652b6ee8..62d47ee54 100644 --- a/src/bin/lttng-sessiond/notification-thread.c +++ b/src/bin/lttng-sessiond/notification-thread.c @@ -42,114 +42,6 @@ #include #include -/** - * This thread maintains an internal state associating clients and triggers. - * - * In order to speed-up and simplify queries, hash tables providing the - * following associations are maintained: - * - * - client_socket_ht: associate a client's socket (fd) to its "struct client" - * This hash table owns the "struct client" which must thus be - * disposed-of on removal from the hash table. - * - * - channel_triggers_ht: - * associates a channel key to a list of - * struct lttng_trigger_list_nodes. The triggers in this list are - * those that have conditions that apply to this channel. - * This hash table owns the list, but not the triggers themselves. - * - * - channel_state_ht: - * associates a pair (channel key, channel domain) to its last - * sampled state received from the consumer daemon - * (struct channel_state). - * This previous sample is kept to implement edge-triggered - * conditions as we need to detect the state transitions. - * This hash table owns the channel state. - * - * - notification_trigger_clients_ht: - * associates notification-emitting triggers to clients - * (struct notification_client_list) subscribed to those - * conditions. - * The condition's hash and match functions are used directly since - * all triggers in this hash table have the "notify" action. - * This hash table holds no ownership. - * - * - channels_ht: - * associates a channel_key to a struct channel_info. The hash table - * holds the ownership of the struct channel_info. - * - * - triggers_ht: - * associated a condition to a struct lttng_trigger_ht_element. - * The hash table holds the ownership of the - * lttng_trigger_ht_elements along with the triggers themselves. - * - * The thread reacts to the following internal events: - * 1) creation of a tracing channel, - * 2) destruction of a tracing channel, - * 3) registration of a trigger, - * 4) unregistration of a trigger, - * 5) reception of a channel monitor sample from the consumer daemon. - * - * Events specific to notification-emitting triggers: - * 6) connection of a notification client, - * 7) disconnection of a notification client, - * 8) subscription of a client to a conditions' notifications, - * 9) unsubscription of a client from a conditions' notifications, - * - * - * 1) Creation of a tracing channel - * - notification_trigger_clients_ht is traversed to identify - * triggers which apply to this new channel, - * - triggers identified are added to the channel_triggers_ht. - * - add channel to channels_ht - * - * 2) Destruction of a tracing channel - * - remove entry from channel_triggers_ht, releasing the list wrapper and - * elements, - * - remove entry from the channel_state_ht. - * - remove channel from channels_ht - * - * 3) Registration of a trigger - * - if the trigger's action is of type "notify", - * - traverse the list of conditions of every client to build a list of - * clients which have to be notified when this trigger's condition is met, - * - add list of clients (even if it is empty) to the - * notification_trigger_clients_ht, - * - add trigger to channel_triggers_ht (if applicable), - * - add trigger to triggers_ht - * - * 4) Unregistration of a trigger - * - if the trigger's action is of type "notify", - * - remove the trigger from the notification_trigger_clients_ht, - * - remove trigger from channel_triggers_ht (if applicable), - * - remove trigger from triggers_ht - * - * 5) Reception of a channel monitor sample from the consumer daemon - * - evaluate the conditions associated with the triggers found in - * the channel_triggers_ht, - * - if a condition evaluates to "true" and the condition is of type - * "notify", query the notification_trigger_clients_ht and send - * a notification to the clients. - * - * 6) Connection of a client - * - add client socket to the client_socket_ht. - * - * 7) Disconnection of a client - * - remove client socket from the client_socket_ht, - * - traverse all conditions to which the client is subscribed and remove - * the client from the notification_trigger_clients_ht. - * - * 8) Subscription of a client to a condition's notifications - * - Add the condition to the client's list of subscribed conditions, - * - Look-up notification_trigger_clients_ht and add the client to - * list of clients. - * - * 9) Unsubscription of a client to a condition's notifications - * - Remove the condition from the client's list of subscribed conditions, - * - Look-up notification_trigger_clients_ht and remove the client - * from the list of clients. - */ - /* * Destroy the thread data previously created by the init function. */ @@ -162,17 +54,12 @@ void notification_thread_handle_destroy( goto end; } - if (handle->cmd_queue.event_fd < 0) { - goto end; - } - ret = close(handle->cmd_queue.event_fd); - if (ret < 0) { - PERROR("close notification command queue event_fd"); - } - assert(cds_list_empty(&handle->cmd_queue.list)); pthread_mutex_destroy(&handle->cmd_queue.lock); + if (handle->cmd_queue.event_pipe) { + lttng_pipe_destroy(handle->cmd_queue.event_pipe); + } if (handle->channel_monitoring_pipes.ust32_consumer >= 0) { ret = close(handle->channel_monitoring_pipes.ust32_consumer); if (ret) { @@ -202,18 +89,22 @@ struct notification_thread_handle *notification_thread_handle_create( { int ret; struct notification_thread_handle *handle; + struct lttng_pipe *event_pipe = NULL; handle = zmalloc(sizeof(*handle)); if (!handle) { goto end; } - /* FIXME Replace eventfd by a pipe to support older kernels. */ - handle->cmd_queue.event_fd = eventfd(0, EFD_CLOEXEC | EFD_SEMAPHORE); - if (handle->cmd_queue.event_fd < 0) { - PERROR("eventfd notification command queue"); + event_pipe = lttng_pipe_open(FD_CLOEXEC); + if (!event_pipe) { + ERR("event_pipe creation"); goto error; } + + handle->cmd_queue.event_pipe = event_pipe; + event_pipe = NULL; + CDS_INIT_LIST_HEAD(&handle->cmd_queue.list); ret = pthread_mutex_init(&handle->cmd_queue.lock, NULL); if (ret) { @@ -253,6 +144,7 @@ struct notification_thread_handle *notification_thread_handle_create( end: return handle; error: + lttng_pipe_destroy(event_pipe); notification_thread_handle_destroy(handle); return NULL; } @@ -344,7 +236,7 @@ int notification_channel_socket_create(void) if (getuid() == 0) { ret = chown(sock_path, 0, - utils_get_group_id(tracing_group_name)); + utils_get_group_id(config.tracing_group_name.value)); if (ret) { ERR("Failed to set the notification channel socket's group"); ret = -1; @@ -390,7 +282,7 @@ int init_poll_set(struct lttng_poll_event *poll_set, ERR("[notification-thread] Failed to add notification channel socket to pollset"); goto error; } - ret = lttng_poll_add(poll_set, handle->cmd_queue.event_fd, + ret = lttng_poll_add(poll_set, lttng_pipe_get_readfd(handle->cmd_queue.event_pipe), LPOLLIN | LPOLLERR); if (ret < 0) { ERR("[notification-thread] Failed to add notification command queue event fd to pollset"); @@ -458,11 +350,13 @@ void fini_thread_state(struct notification_thread_state *state) assert(!ret); } if (state->channels_ht) { - ret = cds_lfht_destroy(state->channels_ht, - NULL); + ret = cds_lfht_destroy(state->channels_ht, NULL); + assert(!ret); + } + if (state->sessions_ht) { + ret = cds_lfht_destroy(state->sessions_ht, NULL); assert(!ret); } - if (state->notification_channel_socket >= 0) { notification_channel_socket_destroy( state->notification_channel_socket); @@ -528,7 +422,11 @@ int init_thread_state(struct notification_thread_handle *handle, if (!state->channels_ht) { goto error; } - + state->sessions_ht = cds_lfht_new(DEFAULT_HT_SIZE, + 1, 0, CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL); + if (!state->sessions_ht) { + goto error; + } state->triggers_ht = cds_lfht_new(DEFAULT_HT_SIZE, 1, 0, CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL); if (!state->triggers_ht) { @@ -652,7 +550,7 @@ void *thread_notification(void *data) ERR("[notification-thread] Unexpected poll events %u for notification socket %i", revents, fd); goto error; } - } else if (fd == handle->cmd_queue.event_fd) { + } else if (fd == lttng_pipe_get_readfd(handle->cmd_queue.event_pipe)) { ret = handle_notification_thread_command(handle, &state); if (ret < 0) {