X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fmain.c;h=ee50db21e38b2c29a400b1ccec0065f72f28900c;hp=489cc9d7646e5643634e04d27e71057beceee930;hb=87597c2c3bbaa1502ad2025cbf16704829f3b464;hpb=d086f507d02078aed618ab291a0bc4a634958fa3 diff --git a/src/bin/lttng-sessiond/main.c b/src/bin/lttng-sessiond/main.c index 489cc9d76..ee50db21e 100644 --- a/src/bin/lttng-sessiond/main.c +++ b/src/bin/lttng-sessiond/main.c @@ -49,6 +49,8 @@ #include #include #include +#include +#include #include "lttng-sessiond.h" #include "buffer-registry.h" @@ -74,7 +76,7 @@ #include "notification-thread.h" #include "notification-thread-commands.h" #include "rotation-thread.h" -#include "syscall.h" +#include "lttng-syscall.h" #include "agent.h" #include "ht-cleanup.h" #include "sessiond-config.h" @@ -299,13 +301,41 @@ struct rotation_thread_handle *rotation_thread_handle; struct lttng_ht *agent_apps_ht_by_sock = NULL; /* - * Whether sessiond is ready for commands/notification channel/health check + * The initialization of the session daemon is done in multiple phases. + * + * While all threads are launched near-simultaneously, only some of them + * are needed to ensure the session daemon can start to respond to client * requests. - * NR_LTTNG_SESSIOND_READY must match the number of calls to - * sessiond_notify_ready(). + * + * There are two important guarantees that we wish to offer with respect + * to the initialisation of the session daemon: + * - When the daemonize/background launcher process exits, the sessiond + * is fully able to respond to client requests, + * - Auto-loaded sessions are visible to clients. + * + * In order to achieve this, a number of support threads have to be launched + * to allow the "client" thread to function properly. Moreover, since the + * "load session" thread needs the client thread, we must provide a way + * for the "load session" thread to know that the "client" thread is up + * and running. + * + * Hence, the support threads decrement the lttng_sessiond_ready counter + * while the "client" threads waits for it to reach 0. Once the "client" thread + * unblocks, it posts the message_thread_ready semaphore which allows the + * "load session" thread to progress. + * + * This implies that the "load session" thread is the last to be initialized + * and will explicitly call sessiond_signal_parents(), which signals the parents + * that the session daemon is fully initialized. + * + * The four (4) support threads are: + * - agent_thread + * - notification_thread + * - rotation_thread + * - health_thread */ -#define NR_LTTNG_SESSIOND_READY 5 -int lttng_sessiond_ready = NR_LTTNG_SESSIOND_READY; +#define NR_LTTNG_SESSIOND_SUPPORT_THREADS 4 +int lttng_sessiond_ready = NR_LTTNG_SESSIOND_SUPPORT_THREADS; int sessiond_check_thread_quit_pipe(int fd, uint32_t events) { @@ -314,28 +344,47 @@ int sessiond_check_thread_quit_pipe(int fd, uint32_t events) /* Notify parents that we are ready for cmd and health check */ LTTNG_HIDDEN -void sessiond_notify_ready(void) +void sessiond_signal_parents(void) { - if (uatomic_sub_return(<tng_sessiond_ready, 1) == 0) { - /* - * Notify parent pid that we are ready to accept command - * for client side. This ppid is the one from the - * external process that spawned us. - */ - if (config.sig_parent) { - kill(ppid, SIGUSR1); - } + /* + * Notify parent pid that we are ready to accept command + * for client side. This ppid is the one from the + * external process that spawned us. + */ + if (config.sig_parent) { + kill(ppid, SIGUSR1); + } - /* - * Notify the parent of the fork() process that we are - * ready. - */ - if (config.daemonize || config.background) { - kill(child_ppid, SIGUSR1); - } + /* + * Notify the parent of the fork() process that we are + * ready. + */ + if (config.daemonize || config.background) { + kill(child_ppid, SIGUSR1); } } +LTTNG_HIDDEN +void sessiond_notify_ready(void) +{ + /* + * This memory barrier is paired with the one performed by + * the client thread after it has seen that 'lttng_sessiond_ready' is 0. + * + * The purpose of these memory barriers is to ensure that all + * initialization operations of the various threads that call this + * function to signal that they are ready are commited/published + * before the client thread can see the 'lttng_sessiond_ready' counter + * reach 0. + * + * Note that this could be a 'write' memory barrier, but a full barrier + * is used in case the code using this utility changes. The performance + * implications of this choice are minimal since this is a slow path. + */ + cmm_smp_mb(); + uatomic_sub(<tng_sessiond_ready, 1); +} + static int __sessiond_set_thread_pollset(struct lttng_poll_event *events, size_t size, int *a_pipe) @@ -544,15 +593,9 @@ static void sessiond_cleanup(void) */ utils_close_pipe(thread_quit_pipe); - /* - * If config.pid_file_path.value is undefined, the default file will be - * wiped when removing the rundir. - */ - if (config.pid_file_path.value) { - ret = remove(config.pid_file_path.value); - if (ret < 0) { - PERROR("remove pidfile %s", config.pid_file_path.value); - } + ret = remove(config.pid_file_path.value); + if (ret < 0) { + PERROR("remove pidfile %s", config.pid_file_path.value); } DBG("Removing sessiond and consumerd content of directory %s", @@ -595,7 +638,8 @@ static void sessiond_cleanup(void) /* Cleanup ALL session */ cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) { - cmd_destroy_session(sess, kernel_poll_pipe[1]); + cmd_destroy_session(sess, kernel_poll_pipe[1], + notification_thread_handle); } } @@ -630,21 +674,6 @@ static void sessiond_cleanup(void) free(load_info); } - /* - * Cleanup lock file by deleting it and finaly closing it which will - * release the file system lock. - */ - if (lockfile_fd >= 0) { - ret = remove(config.lock_file_path.value); - if (ret < 0) { - PERROR("remove lock file"); - } - ret = close(lockfile_fd); - if (ret < 0) { - PERROR("close lock file"); - } - } - /* * We do NOT rmdir rundir because there are other processes * using it, for instance lttng-relayd, which can start in @@ -825,7 +854,7 @@ error: * * Useful for CPU hotplug feature. */ -static int update_kernel_stream(struct consumer_data *consumer_data, int fd) +static int update_kernel_stream(int fd) { int ret = 0; struct ltt_session *session; @@ -874,7 +903,7 @@ static int update_kernel_stream(struct consumer_data *consumer_data, int fd) cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, socket, node.node) { pthread_mutex_lock(socket->lock); - ret = kernel_consumer_send_channel_stream(socket, + ret = kernel_consumer_send_channel_streams(socket, channel, ksess, session->output_traces ? 1 : 0); pthread_mutex_unlock(socket->lock); @@ -1059,7 +1088,7 @@ static void *thread_manage_kernel(void *data) * New CPU detected by the kernel. Adding kernel stream to * kernel session and updating the kernel consumer */ - ret = update_kernel_stream(&kconsumer_data, pollfd); + ret = update_kernel_stream(pollfd); if (ret < 0) { continue; } @@ -2903,6 +2932,128 @@ static unsigned int lttng_sessions_count(uid_t uid, gid_t gid) return i; } +static int receive_userspace_probe(struct command_ctx *cmd_ctx, int sock, + int *sock_error, struct lttng_event *event) +{ + int fd, ret; + struct lttng_userspace_probe_location *probe_location; + const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; + struct lttng_dynamic_buffer probe_location_buffer; + struct lttng_buffer_view buffer_view; + + /* + * Create a buffer to store the serialized version of the probe + * location. + */ + lttng_dynamic_buffer_init(&probe_location_buffer); + ret = lttng_dynamic_buffer_set_size(&probe_location_buffer, + cmd_ctx->lsm->u.enable.userspace_probe_location_len); + if (ret) { + ret = LTTNG_ERR_NOMEM; + goto error; + } + + /* + * Receive the probe location. + */ + ret = lttcomm_recv_unix_sock(sock, probe_location_buffer.data, + probe_location_buffer.size); + if (ret <= 0) { + DBG("Nothing recv() from client var len data... continuing"); + *sock_error = 1; + lttng_dynamic_buffer_reset(&probe_location_buffer); + ret = LTTNG_ERR_PROBE_LOCATION_INVAL; + goto error; + } + + buffer_view = lttng_buffer_view_from_dynamic_buffer( + &probe_location_buffer, 0, probe_location_buffer.size); + + /* + * Extract the probe location from the serialized version. + */ + ret = lttng_userspace_probe_location_create_from_buffer( + &buffer_view, &probe_location); + if (ret < 0) { + WARN("Failed to create a userspace probe location from the received buffer"); + lttng_dynamic_buffer_reset( &probe_location_buffer); + ret = LTTNG_ERR_PROBE_LOCATION_INVAL; + goto error; + } + + /* + * Receive the file descriptor to the target binary from the client. + */ + DBG("Receiving userspace probe target FD from client ..."); + ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1); + if (ret <= 0) { + DBG("Nothing recv() from client userspace probe fd... continuing"); + *sock_error = 1; + ret = LTTNG_ERR_PROBE_LOCATION_INVAL; + goto error; + } + + /* + * Set the file descriptor received from the client through the unix + * socket in the probe location. + */ + lookup = lttng_userspace_probe_location_get_lookup_method(probe_location); + if (!lookup) { + ret = LTTNG_ERR_PROBE_LOCATION_INVAL; + goto error; + } + + /* + * From the kernel tracer's perspective, all userspace probe event types + * are all the same: a file and an offset. + */ + switch (lttng_userspace_probe_location_lookup_method_get_type(lookup)) { + case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF: + ret = lttng_userspace_probe_location_function_set_binary_fd( + probe_location, fd); + break; + case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT: + ret = lttng_userspace_probe_location_tracepoint_set_binary_fd( + probe_location, fd); + break; + default: + ret = LTTNG_ERR_PROBE_LOCATION_INVAL; + goto error; + } + + if (ret) { + ret = LTTNG_ERR_PROBE_LOCATION_INVAL; + goto error; + } + + /* Attach the probe location to the event. */ + ret = lttng_event_set_userspace_probe_location(event, probe_location); + if (ret) { + ret = LTTNG_ERR_PROBE_LOCATION_INVAL; + goto error; + } + + lttng_dynamic_buffer_reset(&probe_location_buffer); +error: + return ret; +} + +/* + * Check if the current kernel tracer supports the session rotation feature. + * Return 1 if it does, 0 otherwise. + */ +static int check_rotate_compatible(void) +{ + int ret = 1; + + if (kernel_tracer_version.major != 2 || kernel_tracer_version.minor < 11) { + DBG("Kernel tracer version is not compatible with the rotation feature"); + ret = 0; + } + + return ret; +} + /* * Process the command requested by the lttng client within the command * context structure. This function make sure that the return structure (llm) @@ -2947,6 +3098,11 @@ static int process_client_msg(struct command_ctx *cmd_ctx, int sock, case LTTNG_REGENERATE_STATEDUMP: case LTTNG_REGISTER_TRIGGER: case LTTNG_UNREGISTER_TRIGGER: + case LTTNG_ROTATE_SESSION: + case LTTNG_ROTATION_GET_INFO: + case LTTNG_SESSION_GET_CURRENT_OUTPUT: + case LTTNG_ROTATION_SET_SCHEDULE: + case LTTNG_SESSION_LIST_ROTATION_SCHEDULES: need_domain = 0; break; default: @@ -2989,6 +3145,9 @@ static int process_client_msg(struct command_ctx *cmd_ctx, int sock, case LTTNG_LIST_SYSCALLS: case LTTNG_LIST_TRACKER_PIDS: case LTTNG_DATA_PENDING: + case LTTNG_ROTATE_SESSION: + case LTTNG_ROTATION_GET_INFO: + case LTTNG_SESSION_LIST_ROTATION_SCHEDULES: break; default: /* Setup lttng message with no payload */ @@ -3417,6 +3576,7 @@ error_add_context: } case LTTNG_ENABLE_EVENT: { + struct lttng_event *ev = NULL; struct lttng_event_exclusion *exclusion = NULL; struct lttng_filter_bytecode *bytecode = NULL; char *filter_expression = NULL; @@ -3468,7 +3628,7 @@ error_add_context: ret = lttcomm_recv_unix_sock(sock, filter_expression, expression_len); if (ret <= 0) { - DBG("Nothing recv() from client car len data... continuing"); + DBG("Nothing recv() from client var len data... continuing"); *sock_error = 1; free(filter_expression); free(exclusion); @@ -3500,7 +3660,7 @@ error_add_context: DBG("Receiving var len filter's bytecode from client ..."); ret = lttcomm_recv_unix_sock(sock, bytecode, bytecode_len); if (ret <= 0) { - DBG("Nothing recv() from client car len data... continuing"); + DBG("Nothing recv() from client var len data... continuing"); *sock_error = 1; free(filter_expression); free(bytecode); @@ -3518,11 +3678,30 @@ error_add_context: } } + ev = lttng_event_copy(&cmd_ctx->lsm->u.enable.event); + if (!ev) { + DBG("Failed to copy event: %s", + cmd_ctx->lsm->u.enable.event.name); + ret = LTTNG_ERR_NOMEM; + goto error; + } + + + if (cmd_ctx->lsm->u.enable.userspace_probe_location_len > 0) { + /* Expect a userspace probe description. */ + ret = receive_userspace_probe(cmd_ctx, sock, sock_error, ev); + if (ret) { + lttng_event_destroy(ev); + goto error; + } + } + ret = cmd_enable_event(cmd_ctx->session, &cmd_ctx->lsm->domain, cmd_ctx->lsm->u.enable.channel_name, - &cmd_ctx->lsm->u.enable.event, + ev, filter_expression, bytecode, exclusion, kernel_poll_pipe[1]); + lttng_event_destroy(ev); break; } case LTTNG_LIST_TRACEPOINTS: @@ -3680,6 +3859,20 @@ error_add_context: } case LTTNG_START_TRACE: { + /* + * On the first start, if we have a kernel session and we have + * enabled time or size-based rotations, we have to make sure + * the kernel tracer supports it. + */ + if (!cmd_ctx->session->has_been_started && \ + cmd_ctx->session->kernel_session && \ + (cmd_ctx->session->rotate_timer_period || \ + cmd_ctx->session->rotate_size) && \ + !check_rotate_compatible()) { + DBG("Kernel tracer version is not compatible with the rotation feature"); + ret = LTTNG_ERR_ROTATION_WRONG_VERSION; + goto error; + } ret = cmd_start_trace(cmd_ctx->session); break; } @@ -3731,7 +3924,8 @@ error_add_context: } case LTTNG_DESTROY_SESSION: { - ret = cmd_destroy_session(cmd_ctx->session, kernel_poll_pipe[1]); + ret = cmd_destroy_session(cmd_ctx->session, kernel_poll_pipe[1], + notification_thread_handle); /* Set session to NULL so we do not unlock it after free. */ cmd_ctx->session = NULL; @@ -4077,6 +4271,125 @@ error_add_context: notification_thread_handle); break; } + case LTTNG_ROTATE_SESSION: + { + struct lttng_rotate_session_return rotate_return; + + DBG("Client rotate session \"%s\"", cmd_ctx->session->name); + + memset(&rotate_return, 0, sizeof(rotate_return)); + if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) { + DBG("Kernel tracer version is not compatible with the rotation feature"); + ret = LTTNG_ERR_ROTATION_WRONG_VERSION; + goto error; + } + + ret = cmd_rotate_session(cmd_ctx->session, &rotate_return); + if (ret < 0) { + ret = -ret; + goto error; + } + + ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &rotate_return, + sizeof(rotate_return)); + if (ret < 0) { + ret = -ret; + goto error; + } + + ret = LTTNG_OK; + break; + } + case LTTNG_ROTATION_GET_INFO: + { + struct lttng_rotation_get_info_return get_info_return; + + memset(&get_info_return, 0, sizeof(get_info_return)); + ret = cmd_rotate_get_info(cmd_ctx->session, &get_info_return, + cmd_ctx->lsm->u.get_rotation_info.rotation_id); + if (ret < 0) { + ret = -ret; + goto error; + } + + ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &get_info_return, + sizeof(get_info_return)); + if (ret < 0) { + ret = -ret; + goto error; + } + + ret = LTTNG_OK; + break; + } + case LTTNG_SESSION_GET_CURRENT_OUTPUT: + { + struct lttng_session_get_current_output_return output_return; + + memset(&output_return, 0, sizeof(output_return)); + ret = cmd_session_get_current_output(cmd_ctx->session, + &output_return); + if (ret < 0) { + ret = -ret; + goto error; + } + + ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &output_return, + sizeof(output_return)); + if (ret < 0) { + ret = -ret; + goto error; + } + + ret = LTTNG_OK; + break; + } + case LTTNG_ROTATION_SET_SCHEDULE: + { + bool set_schedule; + enum lttng_rotation_schedule_type schedule_type; + uint64_t value; + + if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) { + DBG("Kernel tracer version does not support session rotations"); + ret = LTTNG_ERR_ROTATION_WRONG_VERSION; + goto error; + } + + set_schedule = cmd_ctx->lsm->u.rotation_set_schedule.set == 1; + schedule_type = (enum lttng_rotation_schedule_type) cmd_ctx->lsm->u.rotation_set_schedule.type; + value = cmd_ctx->lsm->u.rotation_set_schedule.value; + + ret = cmd_rotation_set_schedule(cmd_ctx->session, + set_schedule, + schedule_type, + value, + notification_thread_handle); + if (ret != LTTNG_OK) { + goto error; + } + + break; + } + case LTTNG_SESSION_LIST_ROTATION_SCHEDULES: + { + struct lttng_session_list_schedules_return schedules = { + .periodic.set = !!cmd_ctx->session->rotate_timer_period, + .periodic.value = cmd_ctx->session->rotate_timer_period, + .size.set = !!cmd_ctx->session->rotate_size, + .size.value = cmd_ctx->session->rotate_size, + }; + + ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &schedules, + sizeof(schedules)); + if (ret < 0) { + ret = -ret; + goto error; + } + + ret = LTTNG_OK; + break; + } default: ret = LTTNG_ERR_UND; break; @@ -4333,13 +4646,50 @@ static void *thread_manage_clients(void *data) goto error; } - sessiond_notify_ready(); ret = sem_post(&load_info->message_thread_ready); if (ret) { PERROR("sem_post message_thread_ready"); goto error; } + /* + * Wait until all support threads are initialized before accepting + * commands. + */ + while (uatomic_read(<tng_sessiond_ready) != 0) { + fd_set read_fds; + struct timeval timeout; + + FD_ZERO(&read_fds); + FD_SET(thread_quit_pipe[0], &read_fds); + memset(&timeout, 0, sizeof(timeout)); + timeout.tv_usec = 1000; + + /* + * If a support thread failed to launch, it may signal that + * we must exit and the sessiond would never be marked as + * "ready". + * + * The timeout is set to 1ms, which serves as a way to + * pace down this check. + */ + ret = select(thread_quit_pipe[0] + 1, &read_fds, NULL, NULL, + &timeout); + if (ret > 0 || (ret < 0 && errno != EINTR)) { + goto exit; + } + } + /* + * This barrier is paired with the one in sessiond_notify_ready() to + * ensure that loads accessing data initialized by the other threads, + * on which this thread was waiting, are not performed before this point. + * + * Note that this could be a 'read' memory barrier, but a full barrier + * is used in case the code changes. The performance implications of + * this choice are minimal since this is a slow path. + */ + cmm_smp_mb(); + /* This testpoint is after we signal readiness to the parent. */ if (testpoint(sessiond_thread_manage_clients)) { goto error; @@ -4352,6 +4702,8 @@ static void *thread_manage_clients(void *data) health_code_update(); while (1) { + const struct cmd_completion_handler *cmd_completion_handler; + DBG("Accepting client command ..."); /* Inifinite blocking call, waiting for transmission */ @@ -4494,6 +4846,18 @@ static void *thread_manage_clients(void *data) continue; } + cmd_completion_handler = cmd_pop_completion_handler(); + if (cmd_completion_handler) { + enum lttng_error_code completion_code; + + completion_code = cmd_completion_handler->run( + cmd_completion_handler->data); + if (completion_code != LTTNG_OK) { + clean_command_ctx(&cmd_ctx); + continue; + } + } + health_code_update(); DBG("Sending response (size: %d, retcode: %s (%d))", @@ -4752,7 +5116,7 @@ static int set_option(int opt, const char *arg, const char *optname) } else if (string_match(optname, "no-kernel")) { config.no_kernel = true; } else if (string_match(optname, "quiet") || opt == 'q') { - lttng_opt_quiet = true; + config.quiet = true; } else if (string_match(optname, "verbose") || opt == 'v') { /* Verbose level can increase using multiple -v */ if (arg) { @@ -4871,8 +5235,8 @@ static int set_option(int opt, const char *arg, const char *optname) ERR("Port overflow in --agent-tcp-port parameter: %s", arg); return -1; } - config.agent_tcp_port = (uint32_t) v; - DBG3("Agent TCP port set to non default: %u", config.agent_tcp_port); + config.agent_tcp_port.begin = config.agent_tcp_port.end = (int) v; + DBG3("Agent TCP port set to non default: %i", (int) v); } } else if (string_match(optname, "load") || opt == 'l') { if (!arg || *arg == '\0') { @@ -5155,18 +5519,57 @@ end: return ret; } +/* + * Create lockfile using the rundir and return its fd. + */ +static int create_lockfile(void) +{ + return utils_create_lock_file(config.lock_file_path.value); +} + /* * Check if the global socket is available, and if a daemon is answering at the * other side. If yes, error is returned. + * + * Also attempts to create and hold the lock file. */ static int check_existing_daemon(void) { + int ret = 0; + /* Is there anybody out there ? */ if (lttng_session_daemon_alive()) { - return -EEXIST; + ret = -EEXIST; + goto end; } - return 0; + lockfile_fd = create_lockfile(); + if (lockfile_fd < 0) { + ret = -EEXIST; + goto end; + } +end: + return ret; +} + +static void sessiond_cleanup_lock_file(void) +{ + int ret; + + /* + * Cleanup lock file by deleting it and finaly closing it which will + * release the file system lock. + */ + if (lockfile_fd >= 0) { + ret = remove(config.lock_file_path.value); + if (ret < 0) { + PERROR("remove lock file"); + } + ret = close(lockfile_fd); + if (ret < 0) { + PERROR("close lock file"); + } + } } /* @@ -5425,23 +5828,6 @@ static int write_pidfile(void) return utils_create_pid_file(getpid(), config.pid_file_path.value); } -/* - * Create lockfile using the rundir and return its fd. - */ -static int create_lockfile(void) -{ - return utils_create_lock_file(config.lock_file_path.value); -} - -/* - * Write agent TCP port using the rundir. - */ -static int write_agent_port(void) -{ - return utils_create_pid_file(config.agent_tcp_port, - config.agent_port_file_path.value); -} - static int set_clock_plugin_env(void) { int ret = 0; @@ -5524,15 +5910,16 @@ int main(int argc, char **argv) struct lttng_pipe *ust32_channel_monitor_pipe = NULL, *ust64_channel_monitor_pipe = NULL, *kernel_channel_monitor_pipe = NULL; - bool notification_thread_running = false; - bool rotation_thread_running = false; - bool timer_thread_running = false; + bool notification_thread_launched = false; + bool rotation_thread_launched = false; + bool timer_thread_launched = false; struct lttng_pipe *ust32_channel_rotate_pipe = NULL, *ust64_channel_rotate_pipe = NULL, *kernel_channel_rotate_pipe = NULL; struct timer_thread_parameters timer_thread_ctx; /* Queue of rotation jobs populated by the sessiond-timer. */ struct rotation_thread_timer_queue *rotation_timer_queue = NULL; + sem_t notification_thread_ready; init_kernel_workarounds(); @@ -5561,6 +5948,12 @@ int main(int argc, char **argv) goto exit_set_signal_handler; } + /* + * Init config from environment variables. + * Command line option override env configuration per-doc. Do env first. + */ + sessiond_config_apply_env_config(&config); + /* * Parse arguments and load the daemon configuration file. * @@ -5575,9 +5968,6 @@ int main(int argc, char **argv) goto exit_options; } - /* Init config from environment variables. */ - sessiond_config_apply_env_config(&config); - /* * Resolve all paths received as arguments, configuration option, or * through environment variable as absolute paths. This is necessary @@ -5608,6 +5998,18 @@ int main(int argc, char **argv) sessiond_config_log(&config); + if (create_lttng_rundir()) { + retval = -1; + goto exit_options; + } + + /* Abort launch if a session daemon is already running. */ + if (check_existing_daemon()) { + ERR("A session daemon is already running."); + retval = -1; + goto exit_options; + } + /* Daemonize */ if (config.daemonize || config.background) { int i; @@ -5622,9 +6024,12 @@ int main(int argc, char **argv) /* * We are in the child. Make sure all other file descriptors are * closed, in case we are called with more opened file - * descriptors than the standard ones. + * descriptors than the standard ones and the lock file. */ for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) { + if (i == lockfile_fd) { + continue; + } (void) close(i); } } @@ -5663,12 +6068,6 @@ int main(int argc, char **argv) /* Check if daemon is UID = 0 */ is_root = !getuid(); - - if (create_lttng_rundir()) { - retval = -1; - goto exit_init_data; - } - if (is_root) { /* Create global run dir with root access */ @@ -5700,12 +6099,6 @@ int main(int argc, char **argv) } } - lockfile_fd = create_lockfile(); - if (lockfile_fd < 0) { - retval = -1; - goto exit_init_data; - } - /* Set consumer initial state */ kernel_consumerd_state = CONSUMER_STOPPED; ust_consumerd_state = CONSUMER_STOPPED; @@ -5772,19 +6165,6 @@ int main(int argc, char **argv) goto exit_init_data; } - /* - * See if daemon already exist. - */ - if (check_existing_daemon()) { - ERR("Already running daemon.\n"); - /* - * We do not goto exit because we must not cleanup() - * because a daemon is already running. - */ - retval = -1; - goto exit_init_data; - } - /* * Init UST app hash table. Alloc hash table before this point since * cleanup() can get called after that point. @@ -5912,12 +6292,6 @@ int main(int argc, char **argv) retval = -1; goto exit_init_data; } - ret = write_agent_port(); - if (ret) { - ERR("Error in write_agent_port"); - retval = -1; - goto exit_init_data; - } /* Initialize communication library */ lttcomm_init(); @@ -5940,11 +6314,19 @@ int main(int argc, char **argv) goto exit_health; } + /* + * The rotation thread needs the notification thread to be ready before + * creating the rotate_notification_channel, so we use this semaphore as + * a rendez-vous point. + */ + sem_init(¬ification_thread_ready, 0, 0); + /* notification_thread_data acquires the pipes' read side. */ notification_thread_handle = notification_thread_handle_create( ust32_channel_monitor_pipe, ust64_channel_monitor_pipe, - kernel_channel_monitor_pipe); + kernel_channel_monitor_pipe, + ¬ification_thread_ready); if (!notification_thread_handle) { retval = -1; ERR("Failed to create notification thread shared data"); @@ -5962,7 +6344,7 @@ int main(int argc, char **argv) stop_threads(); goto exit_notification; } - notification_thread_running = true; + notification_thread_launched = true; /* Create timer thread. */ ret = pthread_create(&timer_thread, default_pthread_attr(), @@ -5974,7 +6356,7 @@ int main(int argc, char **argv) stop_threads(); goto exit_notification; } - timer_thread_running = true; + timer_thread_launched = true; /* rotation_thread_data acquires the pipes' read side. */ rotation_thread_handle = rotation_thread_handle_create( @@ -5982,7 +6364,9 @@ int main(int argc, char **argv) ust64_channel_rotate_pipe, kernel_channel_rotate_pipe, thread_quit_pipe[0], - rotation_timer_queue); + rotation_timer_queue, + notification_thread_handle, + ¬ification_thread_ready); if (!rotation_thread_handle) { retval = -1; ERR("Failed to create rotation thread shared data"); @@ -6000,7 +6384,7 @@ int main(int argc, char **argv) stop_threads(); goto exit_rotation; } - rotation_thread_running = true; + rotation_thread_launched = true; /* Create thread to manage the client socket */ ret = pthread_create(&client_thread, default_pthread_attr(), @@ -6170,6 +6554,7 @@ exit_dispatch: exit_client: exit_rotation: exit_notification: + sem_destroy(¬ification_thread_ready); ret = pthread_join(health_thread, &status); if (ret) { errno = ret; @@ -6205,7 +6590,7 @@ exit_init_data: * of the active session and channels at the moment of the teardown. */ if (notification_thread_handle) { - if (notification_thread_running) { + if (notification_thread_launched) { notification_thread_command_quit( notification_thread_handle); ret = pthread_join(notification_thread, &status); @@ -6219,7 +6604,7 @@ exit_init_data: } if (rotation_thread_handle) { - if (rotation_thread_running) { + if (rotation_thread_launched) { ret = pthread_join(rotation_thread, &status); if (ret) { errno = ret; @@ -6230,7 +6615,7 @@ exit_init_data: rotation_thread_handle_destroy(rotation_thread_handle); } - if (timer_thread_running) { + if (timer_thread_launched) { kill(getpid(), LTTNG_SESSIOND_SIG_EXIT); ret = pthread_join(timer_thread, &status); if (ret) { @@ -6266,6 +6651,7 @@ exit_health_sessiond_cleanup: exit_create_run_as_worker_cleanup: exit_options: + sessiond_cleanup_lock_file(); sessiond_cleanup_options(); exit_set_signal_handler: