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=99cf5173b7e8c3a8320900fafde9ed8df33cbf57;hb=98dfca790cb8fcd3bac11a4f4f58c933f99d2a1a;hpb=526200e44b2ff0c6ad1371bd399a86fd7eaaaa61 diff --git a/src/bin/lttng-sessiond/notification-thread-events.c b/src/bin/lttng-sessiond/notification-thread-events.c index 99cf5173b..ccd285a81 100644 --- a/src/bin/lttng-sessiond/notification-thread-events.c +++ b/src/bin/lttng-sessiond/notification-thread-events.c @@ -21,6 +21,8 @@ #include #include #include +#include +#include #include #include #include @@ -48,6 +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, @@ -125,19 +130,6 @@ struct lttng_condition_list_element { struct cds_list_head node; }; -/* - * Facilities to carry the different notifications type in the action processing - * code path. - */ -struct lttng_event_notifier_notification { - union { - struct lttng_ust_event_notifier_notification *ust; - struct lttng_kernel_event_notifier_notification *kernel; - } notification; - uint64_t token; - enum lttng_domain_type type; -}; - struct channel_state_sample { struct channel_key key; struct cds_lfht_node channel_state_ht_node; @@ -206,6 +198,11 @@ 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); @@ -1993,6 +1990,59 @@ end: 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, @@ -2049,6 +2099,24 @@ int handle_notification_thread_command_remove_tracer_event_source( 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; @@ -4174,37 +4242,30 @@ end: return ret; } -int handle_notification_thread_event_notification(struct notification_thread_state *state, - int notification_pipe_read_fd, - enum lttng_domain_type domain) +static +struct lttng_event_notifier_notification *recv_one_event_notifier_notification( + int notification_pipe_read_fd, enum lttng_domain_type domain) { int ret; - struct lttng_ust_event_notifier_notification ust_notification; - struct lttng_kernel_event_notifier_notification kernel_notification; - struct lttng_evaluation *evaluation = NULL; - struct cds_lfht_node *node; - struct cds_lfht_iter iter; - struct notification_trigger_tokens_ht_element *element; - enum lttng_trigger_status status; - struct lttng_event_notifier_notification notification; + 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; - enum action_executor_status executor_status; - struct notification_client_list *client_list = NULL; - const char *trigger_name; - notification.type = domain; + 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); - notification.notification.ust = &ust_notification; break; case LTTNG_DOMAIN_KERNEL: reception_buffer = (void *) &kernel_notification; reception_size = sizeof(kernel_notification); - notification.notification.kernel = &kernel_notification; break; default: abort(); @@ -4225,20 +4286,79 @@ int handle_notification_thread_event_notification(struct notification_thread_sta switch(domain) { case LTTNG_DOMAIN_UST: - notification.token = ust_notification.token; + token = ust_notification.token; + capture_buffer_size = ust_notification.capture_buf_size; break; case LTTNG_DOMAIN_KERNEL: - notification.token = kernel_notification.token; + 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.token, lttng_ht_seed), - match_trigger_token, ¬ification.token, &iter); + 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)) { /* @@ -4262,15 +4382,37 @@ int handle_notification_thread_event_notification(struct notification_thread_sta lttng_trigger_fire(element->trigger); - status = lttng_trigger_get_name(element->trigger, &trigger_name); - assert(status == LTTNG_TRIGGER_STATUS_OK); - evaluation = lttng_evaluation_event_rule_create(trigger_name); + 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("Failed to create event rule evaluation while creating and enqueuing action executor job"); + 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, @@ -4328,6 +4470,7 @@ next_client: 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"); @@ -4345,6 +4488,40 @@ 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)