X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=blobdiff_plain;f=ltt-sessiond%2Fmain.c;h=7603ffd1417e466f60847c7173092e24038ffc35;hp=de601b6f86746ba295b50ba335b44eb68acf537b;hb=ed8f384d7db2a09cdbd651c0298bfa31992b5a2e;hpb=847177cda88eed885da0b5f0b66b03ffcd06c8f6 diff --git a/ltt-sessiond/main.c b/ltt-sessiond/main.c index de601b6f8..7603ffd14 100644 --- a/ltt-sessiond/main.c +++ b/ltt-sessiond/main.c @@ -3,8 +3,8 @@ * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version 2 - * of the License, or (at your option) any later version. + * as published by the Free Software Foundation; only version 2 + * of the License. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of @@ -21,306 +21,325 @@ #include #include #include +#include #include +#include #include #include #include #include #include +#include #include #include #include #include +#include +#include #include #include /* URCU list library (-lurcu) */ -#include /* UST control lib (-lust) */ #include #include "liblttsessiondcomm.h" #include "ltt-sessiond.h" #include "lttngerr.h" +#include "kernel-ctl.h" +#include "ust-ctl.h" #include "session.h" -#include "trace.h" #include "traceable-app.h" - -/* - * TODO: - * teardown: signal SIGTERM handler -> write into pipe. Threads waits - * with epoll on pipe and on other pipes/sockets for commands. Main - * simply waits on pthread join. - */ +#include "lttng-kconsumerd.h" +#include "utils.h" /* Const values */ const char default_home_dir[] = DEFAULT_HOME_DIR; -const char default_tracing_group[] = DEFAULT_TRACING_GROUP; +const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP; const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR; const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE; -/* Static functions */ -static int check_existing_daemon(void); -static int ust_connect_app(pid_t pid); -static int init_daemon_socket(void); -static int notify_apps(const char* name); -static int process_client_msg(struct command_ctx *cmd_ctx); -static int send_unix_sock(int sock, void *buf, size_t len); -static int set_signal_handler(void); -static int set_permissions(void); -static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size); -static int create_lttng_rundir(void); -static int set_kconsumerd_sockets(void); -static void cleanup(void); -static void sighandler(int sig); -static void clean_command_ctx(struct command_ctx *cmd_ctx); - -static void *thread_manage_clients(void *data); -static void *thread_manage_apps(void *data); -static void *thread_manage_kconsumerd(void *data); - /* Variables */ -int opt_verbose; -int opt_quiet; +int opt_verbose; /* Not static for lttngerr.h */ +int opt_quiet; /* Not static for lttngerr.h */ + const char *progname; const char *opt_tracing_group; static int opt_sig_parent; static int opt_daemon; static int is_root; /* Set to 1 if the daemon is running as root */ -static pid_t ppid; +static pid_t ppid; /* Parent PID for --sig-parent option */ +static pid_t kconsumerd_pid; +static struct pollfd *kernel_pollfd; static char apps_unix_sock_path[PATH_MAX]; /* Global application Unix socket path */ static char client_unix_sock_path[PATH_MAX]; /* Global client Unix socket path */ static char kconsumerd_err_unix_sock_path[PATH_MAX]; /* kconsumerd error Unix socket path */ static char kconsumerd_cmd_unix_sock_path[PATH_MAX]; /* kconsumerd command Unix socket path */ +/* Sockets and FDs */ static int client_sock; static int apps_sock; static int kconsumerd_err_sock; +static int kconsumerd_cmd_sock; +static int kernel_tracer_fd; +static int kernel_poll_pipe[2]; + +/* + * Quit pipe for all threads. This permits a single cancellation point + * for all threads when receiving an event on the pipe. + */ +static int thread_quit_pipe[2]; + +/* Pthread, Mutexes and Semaphores */ +static pthread_t kconsumerd_thread; +static pthread_t apps_thread; +static pthread_t client_thread; +static pthread_t kernel_thread; +static sem_t kconsumerd_sem; + +static pthread_mutex_t kconsumerd_pid_mutex; /* Mutex to control kconsumerd pid assignation */ /* - * thread_manage_kconsumerd + * Pointer initialized before thread creation. * - * This thread manage the kconsumerd error sent - * back to the session daemon. + * This points to the tracing session list containing the session count and a + * mutex lock. The lock MUST be taken if you iterate over the list. The lock + * MUST NOT be taken if you call a public function in session.c. + * + * The lock is nested inside the structure: session_list_ptr->lock. Please use + * lock_session_list and unlock_session_list for lock acquisition. */ -static void *thread_manage_kconsumerd(void *data) -{ - int sock, ret; +static struct ltt_session_list *session_list_ptr; - DBG("[thread] Manage kconsumerd started"); +/* + * Init quit pipe. + * + * Return -1 on error or 0 if all pipes are created. + */ +static int init_thread_quit_pipe(void) +{ + int ret; - ret = lttcomm_listen_unix_sock(kconsumerd_err_sock); + ret = pipe2(thread_quit_pipe, O_CLOEXEC); if (ret < 0) { + perror("thread quit pipe"); goto error; } - sock = lttcomm_accept_unix_sock(kconsumerd_err_sock); - if (sock < 0) { - goto error; - } +error: + return ret; +} - while (1) { - //ret = lttcomm_recv_unix_sock(sock, &lsm, sizeof(lsm)); - if (ret <= 0) { - /* TODO: Consumerd died? */ - continue; - } +/* + * Complete teardown of a kernel session. This free all data structure related + * to a kernel session and update counter. + */ +static void teardown_kernel_session(struct ltt_session *session) +{ + if (session->kernel_session != NULL) { + DBG("Tearing down kernel session"); + trace_destroy_kernel_session(session->kernel_session); + /* Extra precaution */ + session->kernel_session = NULL; } - -error: - return NULL; } /* - * thread_manage_apps - * - * This thread manage the application socket communication + * Cleanup the daemon */ -static void *thread_manage_apps(void *data) +static void cleanup() { - int sock, ret; + int ret; + char *cmd; + struct ltt_session *sess, *stmp; - /* TODO: Something more elegant is needed but fine for now */ - /* FIXME: change all types to either uint8_t, uint32_t, uint64_t - * for 32-bit vs 64-bit compat processes. */ - /* replicate in ust with version number */ - struct { - int reg; /* 1:register, 0:unregister */ - pid_t pid; - uid_t uid; - } reg_msg; + DBG("Cleaning up"); - DBG("[thread] Manage apps started"); + /* */ + MSG("\n%c[%d;%dm*** assert failed *** ==> %c[%dm%c[%d;%dm" + "Matthew, BEET driven development works!%c[%dm", + 27, 1, 31, 27, 0, 27, 1, 33, 27, 0); + /* */ - ret = lttcomm_listen_unix_sock(apps_sock); + /* Stopping all threads */ + DBG("Terminating all threads"); + close(thread_quit_pipe[0]); + close(thread_quit_pipe[1]); + + DBG("Removing %s directory", LTTNG_RUNDIR); + ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR); if (ret < 0) { - goto error; + ERR("asprintf failed. Something is really wrong!"); } - /* Notify all applications to register */ - notify_apps(default_global_apps_pipe); + /* Remove lttng run directory */ + ret = system(cmd); + if (ret < 0) { + ERR("Unable to clean " LTTNG_RUNDIR); + } - while (1) { - /* Blocking call, waiting for transmission */ - sock = lttcomm_accept_unix_sock(apps_sock); - if (sock < 0) { - goto error; - } + DBG("Cleaning up all session"); - /* Basic recv here to handle the very simple data - * that the libust send to register (reg_msg). - */ - ret = recv(sock, ®_msg, sizeof(reg_msg), 0); - if (ret < 0) { - perror("recv"); - continue; - } + /* Destroy session list mutex */ + if (session_list_ptr != NULL) { + pthread_mutex_destroy(&session_list_ptr->lock); - /* Add application to the global traceable list */ - if (reg_msg.reg == 1) { - /* Registering */ - ret = register_traceable_app(reg_msg.pid, reg_msg.uid); - if (ret < 0) { - /* register_traceable_app only return an error with - * ENOMEM. At this point, we better stop everything. - */ - goto error; - } - } else { - /* Unregistering */ - unregister_traceable_app(reg_msg.pid); + /* Cleanup ALL session */ + cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) { + teardown_kernel_session(sess); + // TODO complete session cleanup (including UST) } } -error: + pthread_mutex_destroy(&kconsumerd_pid_mutex); - return NULL; + DBG("Closing kernel fd"); + close(kernel_tracer_fd); } /* - * thread_manage_clients + * Send data on a unix socket using the liblttsessiondcomm API. * - * This thread manage all clients request using the unix - * client socket for communication. + * Return lttcomm error code. */ -static void *thread_manage_clients(void *data) +static int send_unix_sock(int sock, void *buf, size_t len) { - int sock, ret; - struct command_ctx *cmd_ctx; + /* Check valid length */ + if (len <= 0) { + return -1; + } - DBG("[thread] Manage client started"); + return lttcomm_send_unix_sock(sock, buf, len); +} - ret = lttcomm_listen_unix_sock(client_sock); - if (ret < 0) { - goto error; +/* + * Free memory of a command context structure. + */ +static void clean_command_ctx(struct command_ctx **cmd_ctx) +{ + DBG("Clean command context structure"); + if (*cmd_ctx) { + if ((*cmd_ctx)->llm) { + free((*cmd_ctx)->llm); + } + if ((*cmd_ctx)->lsm) { + free((*cmd_ctx)->lsm); + } + free(*cmd_ctx); + *cmd_ctx = NULL; } +} - /* Notify parent pid that we are ready - * to accept command for client side. - */ - if (opt_sig_parent) { - kill(ppid, SIGCHLD); - } +/* + * Send all stream fds of kernel channel to the consumer. + */ +static int send_kconsumerd_channel_fds(int sock, struct ltt_kernel_channel *channel) +{ + int ret; + size_t nb_fd; + struct ltt_kernel_stream *stream; + struct lttcomm_kconsumerd_header lkh; + struct lttcomm_kconsumerd_msg lkm; - while (1) { - /* Blocking call, waiting for transmission */ - DBG("Accepting client command ..."); - sock = lttcomm_accept_unix_sock(client_sock); - if (sock < 0) { - goto error; - } + DBG("Sending fds of channel %s to kernel consumer", channel->channel->name); - /* Allocate context command to process the client request */ - cmd_ctx = malloc(sizeof(struct command_ctx)); + nb_fd = channel->stream_count; - /* Allocate data buffer for reception */ - cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg)); - cmd_ctx->llm = NULL; - cmd_ctx->session = NULL; + /* Setup header */ + lkh.payload_size = nb_fd * sizeof(struct lttcomm_kconsumerd_msg); + lkh.cmd_type = ADD_STREAM; - /* - * Data is received from the lttng client. The struct - * lttcomm_session_msg (lsm) contains the command and data request of - * the client. - */ - DBG("Receiving data from client ..."); - ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm, sizeof(struct lttcomm_session_msg)); - if (ret <= 0) { - continue; - } + DBG("Sending kconsumerd header"); - /* - * This function dispatch the work to the kernel or userspace tracer - * libs and fill the lttcomm_lttng_msg data structure of all the needed - * informations for the client. The command context struct contains - * everything this function may needs. - */ - ret = process_client_msg(cmd_ctx); - if (ret < 0) { - /* TODO: Inform client somehow of the fatal error. At this point, - * ret < 0 means that a malloc failed (ENOMEM). */ - /* Error detected but still accept command */ - clean_command_ctx(cmd_ctx); - continue; - } + ret = lttcomm_send_unix_sock(sock, &lkh, sizeof(struct lttcomm_kconsumerd_header)); + if (ret < 0) { + perror("send kconsumerd header"); + goto error; + } - DBG("Sending response to client (size: %d)", cmd_ctx->lttng_msg_size); - ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size); - if (ret < 0) { - ERR("Failed to send data back to client"); - } + cds_list_for_each_entry(stream, &channel->stream_list.head, list) { + if (stream->fd != 0) { + lkm.fd = stream->fd; + lkm.state = stream->state; + lkm.max_sb_size = channel->channel->attr.subbuf_size; + strncpy(lkm.path_name, stream->pathname, PATH_MAX); + + DBG("Sending fd %d to kconsumerd", lkm.fd); - clean_command_ctx(cmd_ctx); + ret = lttcomm_send_fds_unix_sock(sock, &lkm, &lkm.fd, 1, sizeof(lkm)); + if (ret < 0) { + perror("send kconsumerd fd"); + goto error; + } + } } + DBG("Kconsumerd channel fds sent"); + + return 0; + error: - return NULL; + return ret; } /* - * send_unix_sock - * - * Send data on a unix socket using the liblttsessiondcomm API. - * - * Return lttcomm error code. + * Send all stream fds of the kernel session to the consumer. */ -static int send_unix_sock(int sock, void *buf, size_t len) +static int send_kconsumerd_fds(int sock, struct ltt_kernel_session *session) { - /* Check valid length */ - if (len <= 0) { - return -1; + int ret; + struct ltt_kernel_channel *chan; + struct lttcomm_kconsumerd_header lkh; + struct lttcomm_kconsumerd_msg lkm; + + /* Setup header */ + lkh.payload_size = sizeof(struct lttcomm_kconsumerd_msg); + lkh.cmd_type = ADD_STREAM; + + DBG("Sending kconsumerd header for metadata"); + + ret = lttcomm_send_unix_sock(sock, &lkh, sizeof(struct lttcomm_kconsumerd_header)); + if (ret < 0) { + perror("send kconsumerd header"); + goto error; } - return lttcomm_send_unix_sock(sock, buf, len); -} + DBG("Sending metadata stream fd"); -/* - * clean_command_ctx - * - * Free memory of a command context structure. - */ -static void clean_command_ctx(struct command_ctx *cmd_ctx) -{ - DBG("Clean command context structure %p", cmd_ctx); - if (cmd_ctx) { - if (cmd_ctx->llm) { - free(cmd_ctx->llm); + if (session->metadata_stream_fd != 0) { + /* Send metadata stream fd first */ + lkm.fd = session->metadata_stream_fd; + lkm.state = ACTIVE_FD; + lkm.max_sb_size = session->metadata->conf->attr.subbuf_size; + strncpy(lkm.path_name, session->metadata->pathname, PATH_MAX); + + ret = lttcomm_send_fds_unix_sock(sock, &lkm, &lkm.fd, 1, sizeof(lkm)); + if (ret < 0) { + perror("send kconsumerd fd"); + goto error; } - if (cmd_ctx->lsm) { - free(cmd_ctx->lsm); + } + + cds_list_for_each_entry(chan, &session->channel_list.head, list) { + ret = send_kconsumerd_channel_fds(sock, chan); + if (ret < 0) { + goto error; } - free(cmd_ctx); - cmd_ctx = NULL; } + + DBG("Kconsumerd fds (metadata and channel streams) sent"); + + return 0; + +error: + return ret; } +#ifdef DISABLED /* - * ust_connect_app + * Return a socket connected to the libust communication socket of the + * application identified by the pid. * - * Return a socket connected to the libust communication socket - * of the application identified by the pid. - * - * If the pid is not found in the traceable list, - * return -1 to indicate error. + * If the pid is not found in the traceable list, return -1 to indicate error. */ static int ust_connect_app(pid_t pid) { @@ -338,20 +357,19 @@ static int ust_connect_app(pid_t pid) sock = ustctl_connect_pid(lta->pid); if (sock < 0) { - ERR("Fail connecting to the PID %d\n", pid); + ERR("Fail connecting to the PID %d", pid); } return sock; } +#endif /* DISABLED */ /* - * notify_apps - * - * Notify apps by writing 42 to a named pipe using name. - * Every applications waiting for a ltt-sessiond will be notified - * and re-register automatically to the session daemon. + * Notify apps by writing 42 to a named pipe using name. Every applications + * waiting for a ltt-sessiond will be notified and re-register automatically to + * the session daemon. * - * Return open or write error value. + * Return open or write error value. */ static int notify_apps(const char *name) { @@ -377,24 +395,17 @@ error: } /* - * setup_lttng_msg + * Setup the outgoing data buffer for the response (llm) by allocating the + * right amount of memory and copying the original information from the lsm + * structure. * - * Setup the outgoing data buffer for the response (llm) by allocating the - * right amount of memory and copying the original information from the lsm - * structure. - * - * Return total size of the buffer pointed by buf. + * Return total size of the buffer pointed by buf. */ static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size) { - int ret, buf_size, trace_name_size; + int ret, buf_size; - /* - * Check for the trace_name. If defined, it's part of the payload data of - * the llm structure. - */ - trace_name_size = strlen(cmd_ctx->lsm->trace_name); - buf_size = trace_name_size + size; + buf_size = size; cmd_ctx->llm = malloc(sizeof(struct lttcomm_lttng_msg) + buf_size); if (cmd_ctx->llm == NULL) { @@ -406,17 +417,10 @@ static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size) /* Copy common data */ cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type; cmd_ctx->llm->pid = cmd_ctx->lsm->pid; - if (!uuid_is_null(cmd_ctx->lsm->session_uuid)) { - uuid_copy(cmd_ctx->llm->session_uuid, cmd_ctx->lsm->session_uuid); - } - cmd_ctx->llm->trace_name_offset = trace_name_size; cmd_ctx->llm->data_size = size; cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size; - /* Copy trace name to the llm structure. Begining of the payload. */ - memcpy(cmd_ctx->llm->payload, cmd_ctx->lsm->trace_name, trace_name_size); - return buf_size; error: @@ -424,47 +428,1369 @@ error: } /* - * process_client_msg - * - * Process the command requested by the lttng client within the command - * context structure. This function make sure that the return structure (llm) - * is set and ready for transmission before returning. - * - * Return any error encountered or 0 for success. + * Update the kernel pollfd set of all channel fd available over all tracing + * session. Add the wakeup pipe at the end of the set. */ -static int process_client_msg(struct command_ctx *cmd_ctx) +static int update_kernel_pollfd(void) { - int ret; + int i = 0; + /* + * The wakup pipe and the quit pipe are needed so the number of fds starts + * at 2 for those pipes. + */ + unsigned int nb_fd = 2; + struct ltt_session *session; + struct ltt_kernel_channel *channel; + + DBG("Updating kernel_pollfd"); + + /* Get the number of channel of all kernel session */ + lock_session_list(); + cds_list_for_each_entry(session, &session_list_ptr->head, list) { + lock_session(session); + if (session->kernel_session == NULL) { + unlock_session(session); + continue; + } + nb_fd += session->kernel_session->channel_count; + unlock_session(session); + } - DBG("Processing client command %d", cmd_ctx->lsm->cmd_type); + DBG("Resizing kernel_pollfd to size %d", nb_fd); - /* Check command that needs a session */ - switch (cmd_ctx->lsm->cmd_type) { - case LTTNG_CREATE_SESSION: - case LTTNG_LIST_SESSIONS: - case UST_LIST_APPS: - break; - default: - cmd_ctx->session = find_session_by_uuid(cmd_ctx->lsm->session_uuid); - if (cmd_ctx->session == NULL) { - ret = LTTCOMM_SELECT_SESS; - goto error; - } - break; + kernel_pollfd = realloc(kernel_pollfd, nb_fd * sizeof(struct pollfd)); + if (kernel_pollfd == NULL) { + perror("malloc kernel_pollfd"); + goto error; } - /* Connect to ust apps if available pid */ - if (cmd_ctx->lsm->pid > 0) { - /* Connect to app using ustctl API */ - cmd_ctx->ust_sock = ust_connect_app(cmd_ctx->lsm->pid); - if (cmd_ctx->ust_sock < 0) { - ret = LTTCOMM_NO_TRACEABLE; - goto error; + cds_list_for_each_entry(session, &session_list_ptr->head, list) { + lock_session(session); + if (session->kernel_session == NULL) { + unlock_session(session); + continue; + } + if (i >= nb_fd) { + ERR("To much channel for kernel_pollfd size"); + unlock_session(session); + break; } + cds_list_for_each_entry(channel, &session->kernel_session->channel_list.head, list) { + kernel_pollfd[i].fd = channel->fd; + kernel_pollfd[i].events = POLLIN | POLLRDNORM; + i++; + } + unlock_session(session); + } + unlock_session_list(); + + /* Adding wake up pipe */ + kernel_pollfd[nb_fd - 2].fd = kernel_poll_pipe[0]; + kernel_pollfd[nb_fd - 2].events = POLLIN; + + /* Adding the quit pipe */ + kernel_pollfd[nb_fd - 1].fd = thread_quit_pipe[0]; + + return nb_fd; + +error: + unlock_session_list(); + return -1; +} + +/* + * Find the channel fd from 'fd' over all tracing session. When found, check + * for new channel stream and send those stream fds to the kernel consumer. + * + * Useful for CPU hotplug feature. + */ +static int update_kernel_stream(int fd) +{ + int ret = 0; + struct ltt_session *session; + struct ltt_kernel_channel *channel; + + DBG("Updating kernel streams for channel fd %d", fd); + + lock_session_list(); + cds_list_for_each_entry(session, &session_list_ptr->head, list) { + lock_session(session); + if (session->kernel_session == NULL) { + unlock_session(session); + continue; + } + cds_list_for_each_entry(channel, &session->kernel_session->channel_list.head, list) { + if (channel->fd == fd) { + DBG("Channel found, updating kernel streams"); + ret = kernel_open_channel_stream(channel); + if (ret < 0) { + goto end; + } + /* + * Have we already sent fds to the consumer? If yes, it means that + * tracing is started so it is safe to send our updated stream fds. + */ + if (session->kernel_session->kconsumer_fds_sent == 1) { + ret = send_kconsumerd_channel_fds(kconsumerd_cmd_sock, channel); + if (ret < 0) { + goto end; + } + } + goto end; + } + } + unlock_session(session); + } + +end: + unlock_session_list(); + if (session) { + unlock_session(session); + } + return ret; +} + +/* + * This thread manage event coming from the kernel. + * + * Features supported in this thread: + * -) CPU Hotplug + */ +static void *thread_manage_kernel(void *data) +{ + int ret, i, nb_fd = 0; + char tmp; + int update_poll_flag = 1; + + DBG("Thread manage kernel started"); + + while (1) { + if (update_poll_flag == 1) { + nb_fd = update_kernel_pollfd(); + if (nb_fd < 0) { + goto error; + } + update_poll_flag = 0; + } + + DBG("Polling on %d fds", nb_fd); + + /* Poll infinite value of time */ + ret = poll(kernel_pollfd, nb_fd, -1); + if (ret < 0) { + perror("poll kernel thread"); + goto error; + } else if (ret == 0) { + /* Should not happen since timeout is infinite */ + continue; + } + + /* Thread quit pipe has been closed. Killing thread. */ + if (kernel_pollfd[nb_fd - 1].revents == POLLNVAL) { + goto error; + } + + DBG("Kernel poll event triggered"); + + /* + * Check if the wake up pipe was triggered. If so, the kernel_pollfd + * must be updated. + */ + switch (kernel_pollfd[nb_fd - 2].revents) { + case POLLIN: + ret = read(kernel_poll_pipe[0], &tmp, 1); + update_poll_flag = 1; + continue; + case POLLERR: + goto error; + default: + break; + } + + for (i = 0; i < nb_fd; i++) { + switch (kernel_pollfd[i].revents) { + /* + * New CPU detected by the kernel. Adding kernel stream to kernel + * session and updating the kernel consumer + */ + case POLLIN | POLLRDNORM: + ret = update_kernel_stream(kernel_pollfd[i].fd); + if (ret < 0) { + continue; + } + break; + } + } + } + +error: + DBG("Kernel thread dying"); + if (kernel_pollfd) { + free(kernel_pollfd); + } + + close(kernel_poll_pipe[0]); + close(kernel_poll_pipe[1]); + return NULL; +} + +/* + * This thread manage the kconsumerd error sent back to the session daemon. + */ +static void *thread_manage_kconsumerd(void *data) +{ + int sock = 0, ret; + enum lttcomm_return_code code; + struct pollfd pollfd[2]; + + DBG("[thread] Manage kconsumerd started"); + + ret = lttcomm_listen_unix_sock(kconsumerd_err_sock); + if (ret < 0) { + goto error; + } + + /* First fd is always the quit pipe */ + pollfd[0].fd = thread_quit_pipe[0]; + + /* Apps socket */ + pollfd[1].fd = kconsumerd_err_sock; + pollfd[1].events = POLLIN; + + /* Inifinite blocking call, waiting for transmission */ + ret = poll(pollfd, 2, -1); + if (ret < 0) { + perror("poll kconsumerd thread"); + goto error; + } + + /* Thread quit pipe has been closed. Killing thread. */ + if (pollfd[0].revents == POLLNVAL) { + goto error; + } else if (pollfd[1].revents == POLLERR) { + ERR("Kconsumerd err socket poll error"); + goto error; + } + + sock = lttcomm_accept_unix_sock(kconsumerd_err_sock); + if (sock < 0) { + goto error; + } + + /* Getting status code from kconsumerd */ + ret = lttcomm_recv_unix_sock(sock, &code, sizeof(enum lttcomm_return_code)); + if (ret <= 0) { + goto error; + } + + if (code == KCONSUMERD_COMMAND_SOCK_READY) { + kconsumerd_cmd_sock = lttcomm_connect_unix_sock(kconsumerd_cmd_unix_sock_path); + if (kconsumerd_cmd_sock < 0) { + sem_post(&kconsumerd_sem); + perror("kconsumerd connect"); + goto error; + } + /* Signal condition to tell that the kconsumerd is ready */ + sem_post(&kconsumerd_sem); + DBG("Kconsumerd command socket ready"); + } else { + DBG("Kconsumerd error when waiting for SOCK_READY : %s", + lttcomm_get_readable_code(-code)); + goto error; + } + + /* Wait for any kconsumerd error */ + ret = lttcomm_recv_unix_sock(sock, &code, sizeof(enum lttcomm_return_code)); + if (ret <= 0) { + ERR("Kconsumerd closed the command socket"); + goto error; + } + + ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code)); + +error: + DBG("Kconsumerd thread dying"); + if (kconsumerd_err_sock) { + close(kconsumerd_err_sock); + } + if (kconsumerd_cmd_sock) { + close(kconsumerd_cmd_sock); + } + if (sock) { + close(sock); + } + + unlink(kconsumerd_err_unix_sock_path); + unlink(kconsumerd_cmd_unix_sock_path); + + kconsumerd_pid = 0; + return NULL; +} + +/* + * This thread manage the application socket communication + */ +static void *thread_manage_apps(void *data) +{ + int sock = 0, ret; + struct pollfd pollfd[2]; + + /* TODO: Something more elegant is needed but fine for now */ + /* FIXME: change all types to either uint8_t, uint32_t, uint64_t + * for 32-bit vs 64-bit compat processes. */ + /* replicate in ust with version number */ + struct { + int reg; /* 1:register, 0:unregister */ + pid_t pid; + uid_t uid; + } reg_msg; + + DBG("[thread] Manage apps started"); + + ret = lttcomm_listen_unix_sock(apps_sock); + if (ret < 0) { + goto error; + } + + /* First fd is always the quit pipe */ + pollfd[0].fd = thread_quit_pipe[0]; + + /* Apps socket */ + pollfd[1].fd = apps_sock; + pollfd[1].events = POLLIN; + + /* Notify all applications to register */ + notify_apps(default_global_apps_pipe); + + while (1) { + DBG("Accepting application registration"); + + /* Inifinite blocking call, waiting for transmission */ + ret = poll(pollfd, 2, -1); + if (ret < 0) { + perror("poll apps thread"); + goto error; + } + + /* Thread quit pipe has been closed. Killing thread. */ + if (pollfd[0].revents == POLLNVAL) { + goto error; + } else if (pollfd[1].revents == POLLERR) { + ERR("Apps socket poll error"); + goto error; + } + + sock = lttcomm_accept_unix_sock(apps_sock); + if (sock < 0) { + goto error; + } + + /* + * Basic recv here to handle the very simple data + * that the libust send to register (reg_msg). + */ + ret = recv(sock, ®_msg, sizeof(reg_msg), 0); + if (ret < 0) { + perror("recv"); + continue; + } + + /* Add application to the global traceable list */ + if (reg_msg.reg == 1) { + /* Registering */ + ret = register_traceable_app(reg_msg.pid, reg_msg.uid); + if (ret < 0) { + /* register_traceable_app only return an error with + * ENOMEM. At this point, we better stop everything. + */ + goto error; + } + } else { + /* Unregistering */ + unregister_traceable_app(reg_msg.pid); + } + } + +error: + DBG("Apps thread dying"); + if (apps_sock) { + close(apps_sock); + } + if (sock) { + close(sock); + } + + unlink(apps_unix_sock_path); + return NULL; +} + +/* + * Start the thread_manage_kconsumerd. This must be done after a kconsumerd + * exec or it will fails. + */ +static int spawn_kconsumerd_thread(void) +{ + int ret; + + /* Setup semaphore */ + sem_init(&kconsumerd_sem, 0, 0); + + ret = pthread_create(&kconsumerd_thread, NULL, thread_manage_kconsumerd, (void *) NULL); + if (ret != 0) { + perror("pthread_create kconsumerd"); + goto error; + } + + /* Wait for the kconsumerd thread to be ready */ + sem_wait(&kconsumerd_sem); + + if (kconsumerd_pid == 0) { + ERR("Kconsumerd did not start"); + goto error; + } + + return 0; + +error: + ret = LTTCOMM_KERN_CONSUMER_FAIL; + return ret; +} + +/* + * Fork and exec a kernel consumer daemon (kconsumerd). + * + * Return pid if successful else -1. + */ +static pid_t spawn_kconsumerd(void) +{ + int ret; + pid_t pid; + const char *verbosity; + + DBG("Spawning kconsumerd"); + + pid = fork(); + if (pid == 0) { + /* + * Exec kconsumerd. + */ + if (opt_verbose > 1) { + verbosity = "--verbose"; + } else { + verbosity = "--quiet"; + } + execl(INSTALL_BIN_PATH "/ltt-kconsumerd", "ltt-kconsumerd", verbosity, NULL); + if (errno != 0) { + perror("kernel start consumer exec"); + } + exit(EXIT_FAILURE); + } else if (pid > 0) { + ret = pid; + goto error; + } else { + perror("kernel start consumer fork"); + ret = -errno; + goto error; + } + +error: + return ret; +} + +/* + * Spawn the kconsumerd daemon and session daemon thread. + */ +static int start_kconsumerd(void) +{ + int ret; + + pthread_mutex_lock(&kconsumerd_pid_mutex); + if (kconsumerd_pid != 0) { + pthread_mutex_unlock(&kconsumerd_pid_mutex); + goto end; + } + + ret = spawn_kconsumerd(); + if (ret < 0) { + ERR("Spawning kconsumerd failed"); + ret = LTTCOMM_KERN_CONSUMER_FAIL; + pthread_mutex_unlock(&kconsumerd_pid_mutex); + goto error; + } + + /* Setting up the global kconsumerd_pid */ + kconsumerd_pid = ret; + pthread_mutex_unlock(&kconsumerd_pid_mutex); + + DBG("Kconsumerd pid %d", ret); + + DBG("Spawning kconsumerd thread"); + ret = spawn_kconsumerd_thread(); + if (ret < 0) { + ERR("Fatal error spawning kconsumerd thread"); + goto error; + } + +end: + return 0; + +error: + return ret; +} + +/* + * modprobe_kernel_modules + */ +static int modprobe_kernel_modules(void) +{ + int ret = 0, i = 0; + char modprobe[256]; + + while (kernel_modules_list[i] != NULL) { + ret = snprintf(modprobe, sizeof(modprobe), "/sbin/modprobe %s", + kernel_modules_list[i]); + if (ret < 0) { + perror("snprintf modprobe"); + goto error; + } + ret = system(modprobe); + if (ret < 0) { + ERR("Unable to load module %s", kernel_modules_list[i]); + } + DBG("Modprobe successfully %s", kernel_modules_list[i]); + i++; + } + +error: + return ret; +} + +/* + * mount_debugfs + */ +static int mount_debugfs(char *path) +{ + int ret; + char *type = "debugfs"; + + ret = mkdir_recursive(path, S_IRWXU | S_IRWXG); + if (ret < 0) { + goto error; + } + + ret = mount(type, path, type, 0, NULL); + if (ret < 0) { + perror("mount debugfs"); + goto error; + } + + DBG("Mounted debugfs successfully at %s", path); + +error: + return ret; +} + +/* + * Setup necessary data for kernel tracer action. + */ +static void init_kernel_tracer(void) +{ + int ret; + char *proc_mounts = "/proc/mounts"; + char line[256]; + char *debugfs_path = NULL, *lttng_path; + FILE *fp; + + /* Detect debugfs */ + fp = fopen(proc_mounts, "r"); + if (fp == NULL) { + ERR("Unable to probe %s", proc_mounts); + goto error; + } + + while (fgets(line, sizeof(line), fp) != NULL) { + if (strstr(line, "debugfs") != NULL) { + /* Remove first string */ + strtok(line, " "); + /* Dup string here so we can reuse line later on */ + debugfs_path = strdup(strtok(NULL, " ")); + DBG("Got debugfs path : %s", debugfs_path); + break; + } + } + + fclose(fp); + + /* Mount debugfs if needded */ + if (debugfs_path == NULL) { + ret = asprintf(&debugfs_path, "/mnt/debugfs"); + if (ret < 0) { + perror("asprintf debugfs path"); + goto error; + } + ret = mount_debugfs(debugfs_path); + if (ret < 0) { + goto error; + } + } + + /* Modprobe lttng kernel modules */ + ret = modprobe_kernel_modules(); + if (ret < 0) { + goto error; + } + + /* Setup lttng kernel path */ + ret = asprintf(<tng_path, "%s/lttng", debugfs_path); + if (ret < 0) { + perror("asprintf lttng path"); + goto error; + } + + /* Open debugfs lttng */ + kernel_tracer_fd = open(lttng_path, O_RDWR); + if (kernel_tracer_fd < 0) { + DBG("Failed to open %s", lttng_path); + goto error; + } + + free(lttng_path); + free(debugfs_path); + DBG("Kernel tracer fd %d", kernel_tracer_fd); + return; + +error: + if (lttng_path) { + free(lttng_path); + } + if (debugfs_path) { + free(debugfs_path); + } + WARN("No kernel tracer available"); + kernel_tracer_fd = 0; + return; +} + +/* + * Start tracing by creating trace directory and sending FDs to the kernel + * consumer. + */ +static int start_kernel_trace(struct ltt_kernel_session *session) +{ + int ret = 0; + + if (session->kconsumer_fds_sent == 0) { + ret = send_kconsumerd_fds(kconsumerd_cmd_sock, session); + if (ret < 0) { + ERR("Send kconsumerd fds failed"); + ret = LTTCOMM_KERN_CONSUMER_FAIL; + goto error; + } + + session->kconsumer_fds_sent = 1; + } + +error: + return ret; +} + +/* + * Notify kernel thread to update it's pollfd. + */ +static int notify_kernel_pollfd(void) +{ + int ret; + + /* Inform kernel thread of the new kernel channel */ + ret = write(kernel_poll_pipe[1], "!", 1); + if (ret < 0) { + perror("write kernel poll pipe"); + } + + return ret; +} + +/* + * Allocate a channel structure and fill it. + */ +static struct lttng_channel *init_default_channel(char *name) +{ + struct lttng_channel *chan; + + chan = malloc(sizeof(struct lttng_channel)); + if (chan == NULL) { + perror("init channel malloc"); + goto error; + } + + if (snprintf(chan->name, NAME_MAX, "%s", name) < 0) { + perror("snprintf defautl channel name"); + return NULL; + } + + chan->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE; + chan->attr.subbuf_size = DEFAULT_CHANNEL_SUBBUF_SIZE; + chan->attr.num_subbuf = DEFAULT_CHANNEL_SUBBUF_NUM; + chan->attr.switch_timer_interval = DEFAULT_CHANNEL_SWITCH_TIMER; + chan->attr.read_timer_interval = DEFAULT_CHANNEL_READ_TIMER; + chan->attr.output = DEFAULT_KERNEL_CHANNEL_OUTPUT; + +error: + return chan; +} + +/* + * Create a kernel tracer session then create the default channel. + */ +static int create_kernel_session(struct ltt_session *session) +{ + int ret; + + DBG("Creating kernel session"); + + ret = kernel_create_session(session, kernel_tracer_fd); + if (ret < 0) { + ret = LTTCOMM_KERN_SESS_FAIL; + goto error; + } + + ret = mkdir_recursive(session->path, S_IRWXU | S_IRWXG ); + if (ret < 0) { + if (ret != EEXIST) { + ERR("Trace directory creation error"); + goto error; + } + } + +error: + return ret; +} + +/* + * Using the session list, filled a lttng_session array to send back to the + * client for session listing. + * + * The session list lock MUST be acquired before calling this function. Use + * lock_session_list() and unlock_session_list(). + */ +static void list_lttng_sessions(struct lttng_session *sessions) +{ + int i = 0; + struct ltt_session *session; + + DBG("Getting all available session"); + /* + * Iterate over session list and append data after the control struct in + * the buffer. + */ + cds_list_for_each_entry(session, &session_list_ptr->head, list) { + strncpy(sessions[i].path, session->path, PATH_MAX); + strncpy(sessions[i].name, session->name, NAME_MAX); + i++; + } +} + +/* + * Process the command requested by the lttng client within the command + * context structure. This function make sure that the return structure (llm) + * is set and ready for transmission before returning. + * + * Return any error encountered or 0 for success. + */ +static int process_client_msg(struct command_ctx *cmd_ctx) +{ + int ret = LTTCOMM_OK; + + DBG("Processing client command %d", cmd_ctx->lsm->cmd_type); + + /* Listing commands don't need a session */ + switch (cmd_ctx->lsm->cmd_type) { + case LTTNG_CREATE_SESSION: + case LTTNG_LIST_SESSIONS: + case LTTNG_LIST_EVENTS: + case LTTNG_KERNEL_LIST_EVENTS: + case LTTNG_LIST_TRACEABLE_APPS: + break; + default: + DBG("Getting session %s by name", cmd_ctx->lsm->session_name); + cmd_ctx->session = find_session_by_name(cmd_ctx->lsm->session_name); + if (cmd_ctx->session == NULL) { + /* If session name not found */ + if (cmd_ctx->lsm->session_name != NULL) { + ret = LTTCOMM_SESS_NOT_FOUND; + } else { /* If no session name specified */ + ret = LTTCOMM_SELECT_SESS; + } + goto error; + } else { + /* Acquire lock for the session */ + lock_session(cmd_ctx->session); + } + break; + } + + /* + * Check kernel command for kernel session. + */ + switch (cmd_ctx->lsm->cmd_type) { + case LTTNG_KERNEL_ADD_CONTEXT: + case LTTNG_KERNEL_DISABLE_ALL_EVENT: + case LTTNG_KERNEL_DISABLE_CHANNEL: + case LTTNG_KERNEL_DISABLE_EVENT: + case LTTNG_KERNEL_ENABLE_ALL_EVENT: + case LTTNG_KERNEL_ENABLE_CHANNEL: + case LTTNG_KERNEL_ENABLE_EVENT: + case LTTNG_KERNEL_LIST_EVENTS: + /* Kernel tracer check */ + if (kernel_tracer_fd == 0) { + init_kernel_tracer(); + if (kernel_tracer_fd == 0) { + ret = LTTCOMM_KERN_NA; + goto error; + } + } + + /* Need a session for kernel command */ + if (cmd_ctx->lsm->cmd_type != LTTNG_KERNEL_LIST_EVENTS && + cmd_ctx->session->kernel_session == NULL) { + + ret = create_kernel_session(cmd_ctx->session); + if (ret < 0) { + ret = LTTCOMM_KERN_SESS_FAIL; + goto error; + } + + /* Start the kernel consumer daemon */ + if (kconsumerd_pid == 0) { + ret = start_kconsumerd(); + if (ret < 0) { + goto error; + } + } + } + } + +#ifdef DISABLED + /* Connect to ust apps if available pid */ + if (cmd_ctx->lsm->pid > 0) { + /* Connect to app using ustctl API */ + cmd_ctx->ust_sock = ust_connect_app(cmd_ctx->lsm->pid); + if (cmd_ctx->ust_sock < 0) { + ret = LTTCOMM_NO_TRACEABLE; + goto error; + } + } +#endif /* DISABLED */ + + /* Process by command type */ + switch (cmd_ctx->lsm->cmd_type) { + case LTTNG_KERNEL_ADD_CONTEXT: + { + int found = 0, no_event = 0; + struct ltt_kernel_channel *chan; + struct ltt_kernel_event *event; + struct lttng_kernel_context ctx; + + /* Setup lttng message with no payload */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; + } + + /* Check if event name is given */ + if (strlen(cmd_ctx->lsm->u.context.event_name) == 0) { + no_event = 1; + } + + /* Create Kernel context */ + ctx.ctx = cmd_ctx->lsm->u.context.ctx.ctx; + ctx.u.perf_counter.type = cmd_ctx->lsm->u.context.ctx.u.perf_counter.type; + ctx.u.perf_counter.config = cmd_ctx->lsm->u.context.ctx.u.perf_counter.config; + strncpy(ctx.u.perf_counter.name, + cmd_ctx->lsm->u.context.ctx.u.perf_counter.name, + sizeof(ctx.u.perf_counter.name)); + + if (strlen(cmd_ctx->lsm->u.context.channel_name) == 0) { + /* Go over all channels */ + DBG("Adding context to all channels"); + cds_list_for_each_entry(chan, + &cmd_ctx->session->kernel_session->channel_list.head, list) { + if (no_event) { + ret = kernel_add_channel_context(chan, &ctx); + if (ret < 0) { + continue; + } + } else { + event = get_kernel_event_by_name(cmd_ctx->lsm->u.context.event_name, chan); + if (event != NULL) { + ret = kernel_add_event_context(event, &ctx); + if (ret < 0) { + ret = LTTCOMM_KERN_CONTEXT_FAIL; + goto error; + } + found = 1; + break; + } + } + } + } else { + chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.context.channel_name, + cmd_ctx->session->kernel_session); + if (chan == NULL) { + ret = LTTCOMM_KERN_CHAN_NOT_FOUND; + goto error; + } + + if (no_event) { + ret = kernel_add_channel_context(chan, &ctx); + if (ret < 0) { + ret = LTTCOMM_KERN_CONTEXT_FAIL; + goto error; + } + } else { + event = get_kernel_event_by_name(cmd_ctx->lsm->u.context.event_name, chan); + if (event != NULL) { + ret = kernel_add_event_context(event, &ctx); + if (ret < 0) { + ret = LTTCOMM_KERN_CONTEXT_FAIL; + goto error; + } + } + } + } + + if (!found && !no_event) { + ret = LTTCOMM_NO_EVENT; + goto error; + } + + ret = LTTCOMM_OK; + break; + } + case LTTNG_KERNEL_DISABLE_CHANNEL: + { + struct ltt_kernel_channel *chan; + + /* Setup lttng message with no payload */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; + } + + chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.disable.channel_name, + cmd_ctx->session->kernel_session); + if (chan == NULL) { + ret = LTTCOMM_KERN_CHAN_NOT_FOUND; + goto error; + } else if (chan->enabled == 1) { + ret = kernel_disable_channel(chan); + if (ret < 0) { + if (ret != EEXIST) { + ret = LTTCOMM_KERN_CHAN_DISABLE_FAIL; + } + goto error; + } + } + + kernel_wait_quiescent(kernel_tracer_fd); + ret = LTTCOMM_OK; + break; + } + case LTTNG_KERNEL_DISABLE_EVENT: + { + struct ltt_kernel_channel *chan; + struct ltt_kernel_event *ev; + + /* Setup lttng message with no payload */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; + } + + chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.disable.channel_name, + cmd_ctx->session->kernel_session); + if (chan == NULL) { + ret = LTTCOMM_KERN_CHAN_NOT_FOUND; + goto error; + } + + ev = get_kernel_event_by_name(cmd_ctx->lsm->u.disable.name, chan); + if (ev != NULL) { + DBG("Disabling kernel event %s for channel %s.", + cmd_ctx->lsm->u.disable.name, cmd_ctx->lsm->u.disable.channel_name); + ret = kernel_disable_event(ev); + if (ret < 0) { + ret = LTTCOMM_KERN_ENABLE_FAIL; + goto error; + } + } + + kernel_wait_quiescent(kernel_tracer_fd); + ret = LTTCOMM_OK; + break; + } + case LTTNG_KERNEL_DISABLE_ALL_EVENT: + { + struct ltt_kernel_channel *chan; + struct ltt_kernel_event *ev; + + /* Setup lttng message with no payload */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; + } + + DBG("Disabling all enabled kernel events"); + + chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.disable.channel_name, + cmd_ctx->session->kernel_session); + if (chan == NULL) { + ret = LTTCOMM_KERN_CHAN_NOT_FOUND; + goto error; + } + + /* For each event in the kernel session */ + cds_list_for_each_entry(ev, &chan->events_list.head, list) { + DBG("Disabling kernel event %s for channel %s.", + ev->event->name, cmd_ctx->lsm->u.disable.channel_name); + ret = kernel_disable_event(ev); + if (ret < 0) { + continue; + } + } + + /* Quiescent wait after event disable */ + kernel_wait_quiescent(kernel_tracer_fd); + ret = LTTCOMM_OK; + break; + } + case LTTNG_KERNEL_ENABLE_CHANNEL: + { + struct ltt_kernel_channel *chan; + + /* Setup lttng message with no payload */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; + } + + chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.enable.channel_name, + cmd_ctx->session->kernel_session); + if (chan == NULL) { + /* Channel not found, creating it */ + DBG("Creating kernel channel"); + + ret = kernel_create_channel(cmd_ctx->session->kernel_session, + &cmd_ctx->lsm->u.channel.chan, cmd_ctx->session->path); + if (ret < 0) { + ret = LTTCOMM_KERN_CHAN_FAIL; + goto error; + } + + /* Notify kernel thread that there is a new channel */ + ret = notify_kernel_pollfd(); + if (ret < 0) { + ret = LTTCOMM_FATAL; + goto error; + } + } else if (chan->enabled == 0) { + ret = kernel_enable_channel(chan); + if (ret < 0) { + if (ret != EEXIST) { + ret = LTTCOMM_KERN_CHAN_ENABLE_FAIL; + } + goto error; + } + } + + kernel_wait_quiescent(kernel_tracer_fd); + ret = LTTCOMM_OK; + break; + } + case LTTNG_KERNEL_ENABLE_EVENT: + { + char *channel_name; + struct ltt_kernel_channel *kchan; + struct ltt_kernel_event *ev; + struct lttng_channel *chan; + + /* Setup lttng message with no payload */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; + } + + channel_name = cmd_ctx->lsm->u.enable.channel_name; + + do { + kchan = get_kernel_channel_by_name(channel_name, + cmd_ctx->session->kernel_session); + if (kchan == NULL) { + DBG("Channel not found. Creating channel %s", channel_name); + + chan = init_default_channel(channel_name); + if (chan == NULL) { + ret = LTTCOMM_FATAL; + goto error; + } + + ret = kernel_create_channel(cmd_ctx->session->kernel_session, + chan, cmd_ctx->session->path); + if (ret < 0) { + ret = LTTCOMM_KERN_CHAN_FAIL; + goto error; + } + } + } while (kchan == NULL); + + ev = get_kernel_event_by_name(cmd_ctx->lsm->u.enable.event.name, kchan); + if (ev == NULL) { + DBG("Creating kernel event %s for channel %s.", + cmd_ctx->lsm->u.enable.event.name, channel_name); + ret = kernel_create_event(&cmd_ctx->lsm->u.enable.event, kchan); + } else { + DBG("Enabling kernel event %s for channel %s.", + cmd_ctx->lsm->u.enable.event.name, channel_name); + ret = kernel_enable_event(ev); + if (ret == -EEXIST) { + ret = LTTCOMM_KERN_EVENT_EXIST; + goto error; + } + } + + if (ret < 0) { + ret = LTTCOMM_KERN_ENABLE_FAIL; + goto error; + } + + kernel_wait_quiescent(kernel_tracer_fd); + ret = LTTCOMM_OK; + break; + } + case LTTNG_KERNEL_ENABLE_ALL_EVENT: + { + int pos, size; + char *event_list, *event, *ptr, *channel_name; + struct ltt_kernel_channel *kchan; + struct ltt_kernel_event *ev; + struct lttng_event ev_attr; + struct lttng_channel *chan; + + /* Setup lttng message with no payload */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; + } + + DBG("Enabling all kernel event"); + + channel_name = cmd_ctx->lsm->u.enable.channel_name; + + do { + kchan = get_kernel_channel_by_name(channel_name, + cmd_ctx->session->kernel_session); + if (kchan == NULL) { + DBG("Channel not found. Creating channel %s", channel_name); + + chan = init_default_channel(channel_name); + if (chan == NULL) { + ret = LTTCOMM_FATAL; + goto error; + } + + ret = kernel_create_channel(cmd_ctx->session->kernel_session, + chan, cmd_ctx->session->path); + if (ret < 0) { + ret = LTTCOMM_KERN_CHAN_FAIL; + goto error; + } + } + } while (kchan == NULL); + + /* For each event in the kernel session */ + cds_list_for_each_entry(ev, &kchan->events_list.head, list) { + DBG("Enabling kernel event %s for channel %s.", + ev->event->name, channel_name); + ret = kernel_enable_event(ev); + if (ret < 0) { + continue; + } + } + + size = kernel_list_events(kernel_tracer_fd, &event_list); + if (size < 0) { + ret = LTTCOMM_KERN_LIST_FAIL; + goto error; + } + + ptr = event_list; + while ((size = sscanf(ptr, "event { name = %m[^;]; };%n\n", &event, &pos)) == 1) { + ev = get_kernel_event_by_name(event, kchan); + if (ev == NULL) { + strncpy(ev_attr.name, event, LTTNG_SYM_NAME_LEN); + /* Default event type for enable all */ + ev_attr.type = LTTNG_EVENT_TRACEPOINT; + /* Enable each single tracepoint event */ + ret = kernel_create_event(&ev_attr, kchan); + if (ret < 0) { + /* Ignore error here and continue */ + } + } + + /* Move pointer to the next line */ + ptr += pos + 1; + free(event); + } + + free(event_list); + + /* Quiescent wait after event enable */ + kernel_wait_quiescent(kernel_tracer_fd); + ret = LTTCOMM_OK; + break; + } + case LTTNG_KERNEL_LIST_EVENTS: + { + char *event_list; + ssize_t size = 0; + + DBG("Listing kernel events"); + + size = kernel_list_events(kernel_tracer_fd, &event_list); + if (size < 0) { + ret = LTTCOMM_KERN_LIST_FAIL; + goto error; + } + + /* + * Setup lttng message with payload size set to the event list size in + * bytes and then copy list into the llm payload. + */ + ret = setup_lttng_msg(cmd_ctx, size); + if (ret < 0) { + goto setup_error; + } + + /* Copy event list into message payload */ + memcpy(cmd_ctx->llm->payload, event_list, size); + + free(event_list); + + ret = LTTCOMM_OK; + break; + } + case LTTNG_START_TRACE: + { + struct ltt_kernel_channel *chan; + + /* Setup lttng message with no payload */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; + } + + /* Kernel tracing */ + if (cmd_ctx->session->kernel_session != NULL) { + if (cmd_ctx->session->kernel_session->metadata == NULL) { + DBG("Open kernel metadata"); + ret = kernel_open_metadata(cmd_ctx->session->kernel_session, + cmd_ctx->session->path); + if (ret < 0) { + ret = LTTCOMM_KERN_META_FAIL; + goto error; + } + } + + if (cmd_ctx->session->kernel_session->metadata_stream_fd == 0) { + DBG("Opening kernel metadata stream"); + if (cmd_ctx->session->kernel_session->metadata_stream_fd == 0) { + ret = kernel_open_metadata_stream(cmd_ctx->session->kernel_session); + if (ret < 0) { + ERR("Kernel create metadata stream failed"); + ret = LTTCOMM_KERN_STREAM_FAIL; + goto error; + } + } + } + + /* For each channel */ + cds_list_for_each_entry(chan, &cmd_ctx->session->kernel_session->channel_list.head, list) { + if (chan->stream_count == 0) { + ret = kernel_open_channel_stream(chan); + if (ret < 0) { + ERR("Kernel create channel stream failed"); + ret = LTTCOMM_KERN_STREAM_FAIL; + goto error; + } + /* Update the stream global counter */ + cmd_ctx->session->kernel_session->stream_count_global += ret; + } + } + + DBG("Start kernel tracing"); + ret = kernel_start_session(cmd_ctx->session->kernel_session); + if (ret < 0) { + ERR("Kernel start session failed"); + ret = LTTCOMM_KERN_START_FAIL; + goto error; + } + + ret = start_kernel_trace(cmd_ctx->session->kernel_session); + if (ret < 0) { + ret = LTTCOMM_KERN_START_FAIL; + goto error; + } + + /* Quiescent wait after starting trace */ + kernel_wait_quiescent(kernel_tracer_fd); + } + + /* TODO: Start all UST traces */ + + ret = LTTCOMM_OK; + break; + } + case LTTNG_STOP_TRACE: + { + struct ltt_kernel_channel *chan; + /* Setup lttng message with no payload */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; + } + + /* Kernel tracer */ + if (cmd_ctx->session->kernel_session != NULL) { + DBG("Stop kernel tracing"); + + ret = kernel_metadata_flush_buffer(cmd_ctx->session->kernel_session->metadata_stream_fd); + if (ret < 0) { + ERR("Kernel metadata flush failed"); + } + + cds_list_for_each_entry(chan, &cmd_ctx->session->kernel_session->channel_list.head, list) { + ret = kernel_flush_buffer(chan); + if (ret < 0) { + ERR("Kernel flush buffer error"); + } + } + + ret = kernel_stop_session(cmd_ctx->session->kernel_session); + if (ret < 0) { + ERR("Kernel stop session failed"); + ret = LTTCOMM_KERN_STOP_FAIL; + goto error; + } + + /* Quiescent wait after stopping trace */ + kernel_wait_quiescent(kernel_tracer_fd); + } + + /* TODO : User-space tracer */ + + ret = LTTCOMM_OK; + break; } - - /* Process by command type */ - switch (cmd_ctx->lsm->cmd_type) { case LTTNG_CREATE_SESSION: { /* Setup lttng message with no payload */ @@ -473,9 +1799,9 @@ static int process_client_msg(struct command_ctx *cmd_ctx) goto setup_error; } - ret = create_session(cmd_ctx->lsm->session_name, &cmd_ctx->llm->session_uuid); + ret = create_session(cmd_ctx->lsm->session_name, cmd_ctx->lsm->path); if (ret < 0) { - if (ret == -1) { + if (ret == -EEXIST) { ret = LTTCOMM_EXIST_SESS; } else { ret = LTTCOMM_FATAL; @@ -494,15 +1820,29 @@ static int process_client_msg(struct command_ctx *cmd_ctx) goto setup_error; } - ret = destroy_session(&cmd_ctx->lsm->session_uuid); + /* Clean kernel session teardown */ + teardown_kernel_session(cmd_ctx->session); + + ret = destroy_session(cmd_ctx->lsm->session_name); + if (ret < 0) { + ret = LTTCOMM_FATAL; + goto error; + } + + /* + * Must notify the kernel thread here to update it's pollfd in order to + * remove the channel(s)' fd just destroyed. + */ + ret = notify_kernel_pollfd(); if (ret < 0) { - ret = LTTCOMM_NO_SESS; + ret = LTTCOMM_FATAL; goto error; } ret = LTTCOMM_OK; break; } + /* case LTTNG_LIST_TRACES: { unsigned int trace_count; @@ -524,9 +1864,10 @@ static int process_client_msg(struct command_ctx *cmd_ctx) ret = LTTCOMM_OK; break; } + */ + /* case UST_CREATE_TRACE: { - /* Setup lttng message with no payload */ ret = setup_lttng_msg(cmd_ctx, 0); if (ret < 0) { goto setup_error; @@ -534,11 +1875,12 @@ static int process_client_msg(struct command_ctx *cmd_ctx) ret = ust_create_trace(cmd_ctx); if (ret < 0) { - goto setup_error; + goto error; } break; } - case UST_LIST_APPS: + */ + case LTTNG_LIST_TRACEABLE_APPS: { unsigned int app_count; @@ -559,9 +1901,9 @@ static int process_client_msg(struct command_ctx *cmd_ctx) ret = LTTCOMM_OK; break; } + /* case UST_START_TRACE: { - /* Setup lttng message with no payload */ ret = setup_lttng_msg(cmd_ctx, 0); if (ret < 0) { goto setup_error; @@ -575,7 +1917,6 @@ static int process_client_msg(struct command_ctx *cmd_ctx) } case UST_STOP_TRACE: { - /* Setup lttng message with no payload */ ret = setup_lttng_msg(cmd_ctx, 0); if (ret < 0) { goto setup_error; @@ -587,22 +1928,26 @@ static int process_client_msg(struct command_ctx *cmd_ctx) } break; } + */ case LTTNG_LIST_SESSIONS: { - unsigned int session_count; + lock_session_list(); - session_count = get_session_count(); - if (session_count == 0) { - ret = LTTCOMM_NO_SESS; + if (session_list_ptr->count == 0) { + ret = LTTCOMM_NO_SESSION; goto error; } - ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * session_count); + ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * + session_list_ptr->count); if (ret < 0) { goto setup_error; } - get_lttng_session((struct lttng_session *)(cmd_ctx->llm->payload)); + /* Filled the session array */ + list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload)); + + unlock_session_list(); ret = LTTCOMM_OK; break; @@ -621,15 +1966,16 @@ static int process_client_msg(struct command_ctx *cmd_ctx) /* Set return code */ cmd_ctx->llm->ret_code = ret; + if (cmd_ctx->session) { + unlock_session(cmd_ctx->session); + } + return ret; error: - DBG("Return code to client %d", ret); - if (cmd_ctx->llm == NULL) { DBG("Missing llm structure. Allocating one."); - ret = setup_lttng_msg(cmd_ctx, 0); - if (ret < 0) { + if (setup_lttng_msg(cmd_ctx, 0) < 0) { goto setup_error; } } @@ -637,9 +1983,131 @@ error: cmd_ctx->llm->ret_code = ret; setup_error: + if (cmd_ctx->session) { + unlock_session(cmd_ctx->session); + } return ret; } +/* + * This thread manage all clients request using the unix client socket for + * communication. + */ +static void *thread_manage_clients(void *data) +{ + int sock = 0, ret; + struct command_ctx *cmd_ctx = NULL; + struct pollfd pollfd[2]; + + DBG("[thread] Manage client started"); + + ret = lttcomm_listen_unix_sock(client_sock); + if (ret < 0) { + goto error; + } + + /* First fd is always the quit pipe */ + pollfd[0].fd = thread_quit_pipe[0]; + + /* Apps socket */ + pollfd[1].fd = client_sock; + pollfd[1].events = POLLIN; + + /* Notify parent pid that we are ready + * to accept command for client side. + */ + if (opt_sig_parent) { + kill(ppid, SIGCHLD); + } + + while (1) { + DBG("Accepting client command ..."); + + /* Inifinite blocking call, waiting for transmission */ + ret = poll(pollfd, 2, -1); + if (ret < 0) { + perror("poll client thread"); + goto error; + } + + /* Thread quit pipe has been closed. Killing thread. */ + if (pollfd[0].revents == POLLNVAL) { + goto error; + } else if (pollfd[1].revents == POLLERR) { + ERR("Client socket poll error"); + goto error; + } + + sock = lttcomm_accept_unix_sock(client_sock); + if (sock < 0) { + goto error; + } + + /* Allocate context command to process the client request */ + cmd_ctx = malloc(sizeof(struct command_ctx)); + + /* Allocate data buffer for reception */ + cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg)); + cmd_ctx->llm = NULL; + cmd_ctx->session = NULL; + + /* + * Data is received from the lttng client. The struct + * lttcomm_session_msg (lsm) contains the command and data request of + * the client. + */ + DBG("Receiving data from client ..."); + ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm, sizeof(struct lttcomm_session_msg)); + if (ret <= 0) { + continue; + } + + // TODO: Validate cmd_ctx including sanity check for security purpose. + + /* + * This function dispatch the work to the kernel or userspace tracer + * libs and fill the lttcomm_lttng_msg data structure of all the needed + * informations for the client. The command context struct contains + * everything this function may needs. + */ + ret = process_client_msg(cmd_ctx); + if (ret < 0) { + /* TODO: Inform client somehow of the fatal error. At this point, + * ret < 0 means that a malloc failed (ENOMEM). */ + /* Error detected but still accept command */ + clean_command_ctx(&cmd_ctx); + continue; + } + + DBG("Sending response (size: %d, retcode: %d)", + cmd_ctx->lttng_msg_size, cmd_ctx->llm->ret_code); + ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size); + if (ret < 0) { + ERR("Failed to send data back to client"); + } + + clean_command_ctx(&cmd_ctx); + + /* End of transmission */ + close(sock); + } + +error: + DBG("Client thread dying"); + if (client_sock) { + close(client_sock); + } + if (sock) { + close(sock); + } + + unlink(client_unix_sock_path); + + clean_command_ctx(&cmd_ctx); + return NULL; +} + + /* * usage function on stderr */ @@ -726,7 +2194,8 @@ static int parse_args(int argc, char **argv) opt_quiet = 1; break; case 'v': - opt_verbose = 1; + /* Verbose level can increase using multiple -v */ + opt_verbose += 1; break; default: /* Unknown option or other error. @@ -739,9 +2208,7 @@ static int parse_args(int argc, char **argv) } /* - * init_daemon_socket - * - * Creates the two needed socket by the daemon. + * Creates the two needed socket by the daemon. * apps_sock - The communication socket for all UST apps. * client_sock - The communication of the cli tool (lttng). */ @@ -790,10 +2257,7 @@ end: } /* - * check_existing_daemon - * - * Check if the global socket is available. - * If yes, error is returned. + * Check if the global socket is available. If yes, error is returned. */ static int check_existing_daemon() { @@ -808,31 +2272,10 @@ static int check_existing_daemon() } /* - * get_home_dir - * - * Return pointer to home directory path using - * the env variable HOME. - * - * Default : /tmp - */ -static const char *get_home_dir(void) -{ - const char *home_path; - - if ((home_path = (const char *) getenv("HOME")) == NULL) { - home_path = default_home_dir; - } - - return home_path; -} - -/* - * set_permissions + * Set the tracing group gid onto the client socket. * - * Set the tracing group gid onto the client socket. - * - * Race window between mkdir and chown is OK because we are going from - * less permissive (root.root) to more permissive (root.tracing). + * Race window between mkdir and chown is OK because we are going from more + * permissive (root.root) to les permissive (root.tracing). */ static int set_permissions(void) { @@ -845,8 +2288,13 @@ static int set_permissions(void) (grp = getgrnam(default_tracing_group)); if (grp == NULL) { - ERR("Missing tracing group. Aborting execution.\n"); - ret = -1; + if (is_root) { + WARN("No tracing group detected"); + ret = 0; + } else { + ERR("Missing tracing group. Aborting execution."); + ret = -1; + } goto end; } @@ -878,10 +2326,15 @@ end: } /* - * create_lttng_rundir - * - * Create the lttng run directory needed for all - * global sockets and pipe. + * Create the pipe used to wake up the kernel thread. + */ +static int create_kernel_poll_pipe(void) +{ + return pipe2(kernel_poll_pipe, O_CLOEXEC); +} + +/* + * Create the lttng run directory needed for all global sockets and pipe. */ static int create_lttng_rundir(void) { @@ -889,8 +2342,12 @@ static int create_lttng_rundir(void) ret = mkdir(LTTNG_RUNDIR, S_IRWXU | S_IRWXG ); if (ret < 0) { - ERR("Unable to create " LTTNG_RUNDIR); - goto error; + if (errno != EEXIST) { + ERR("Unable to create " LTTNG_RUNDIR); + goto error; + } else { + ret = 0; + } } error: @@ -898,10 +2355,8 @@ error: } /* - * set_kconsumerd_sockets - * - * Setup sockets and directory needed by the kconsumerd - * communication with the session daemon. + * Setup sockets and directory needed by the kconsumerd communication with the + * session daemon. */ static int set_kconsumerd_sockets(void) { @@ -917,8 +2372,11 @@ static int set_kconsumerd_sockets(void) ret = mkdir(KCONSUMERD_PATH, S_IRWXU | S_IRWXG); if (ret < 0) { - ERR("Failed to create " KCONSUMERD_PATH); - goto error; + if (errno != EEXIST) { + ERR("Failed to create " KCONSUMERD_PATH); + goto error; + } + ret = 0; } /* Create the kconsumerd error unix socket */ @@ -942,9 +2400,31 @@ error: } /* - * set_signal_handler - * - * Setup signal handler for : + * Signal handler for the daemon + */ +static void sighandler(int sig) +{ + switch (sig) { + case SIGPIPE: + DBG("SIGPIPE catched"); + return; + case SIGINT: + DBG("SIGINT catched"); + cleanup(); + break; + case SIGTERM: + DBG("SIGTERM catched"); + cleanup(); + break; + default: + break; + } + + exit(EXIT_SUCCESS); +} + +/* + * Setup signal handler for : * SIGINT, SIGTERM, SIGPIPE */ static int set_signal_handler(void) @@ -981,62 +2461,22 @@ static int set_signal_handler(void) return ret; } -/** - * sighandler - * - * Signal handler for the daemon - */ -static void sighandler(int sig) -{ - switch (sig) { - case SIGPIPE: - DBG("SIGPIPE catched"); - return; - case SIGINT: - DBG("SIGINT catched"); - cleanup(); - break; - case SIGTERM: - DBG("SIGTERM catched"); - cleanup(); - break; - default: - break; - } - - exit(EXIT_SUCCESS); -} - /* - * cleanup - * - * Cleanup the daemon on exit + * Set open files limit to unlimited. This daemon can open a large number of + * file descriptors in order to consumer multiple kernel traces. */ -static void cleanup() +static void set_ulimit(void) { int ret; - char *cmd; - - DBG("Cleaning up"); - - /* */ - MSG("\n%c[%d;%dm*** assert failed *** ==> %c[%dm", 27,1,31,27,0); - MSG("%c[%d;%dmMatthew, BEET driven development works!%c[%dm",27,1,33,27,0); - /* */ - - unlink(client_unix_sock_path); - unlink(apps_unix_sock_path); - unlink(kconsumerd_err_unix_sock_path); + struct rlimit lim; - ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR); - if (ret < 0) { - ERR("asprintf failed. Something is really wrong!"); - } + /* The kernel does not allowed an infinite limit for open files */ + lim.rlim_cur = 65535; + lim.rlim_max = 65535; - /* Remove lttng run directory */ - ret = system(cmd); + ret = setrlimit(RLIMIT_NOFILE, &lim); if (ret < 0) { - ERR("Unable to clean " LTTNG_RUNDIR); + perror("failed to set open files limit"); } } @@ -1045,15 +2485,19 @@ static void cleanup() */ int main(int argc, char **argv) { - int i; int ret = 0; void *status; - pthread_t threads[2]; + const char *home_path; + + /* Create thread quit pipe */ + if (init_thread_quit_pipe() < 0) { + goto exit; + } /* Parse arguments */ progname = argv[0]; if ((ret = parse_args(argc, argv) < 0)) { - goto error; + goto exit; } /* Daemonize */ @@ -1061,18 +2505,17 @@ int main(int argc, char **argv) ret = daemon(0, 0); if (ret < 0) { perror("daemon"); - goto error; + goto exit; } } /* Check if daemon is UID = 0 */ is_root = !getuid(); - /* Set all sockets path */ if (is_root) { ret = create_lttng_rundir(); if (ret < 0) { - goto error; + goto exit; } if (strlen(apps_unix_sock_path) == 0) { @@ -1084,36 +2527,62 @@ int main(int argc, char **argv) snprintf(client_unix_sock_path, PATH_MAX, DEFAULT_GLOBAL_CLIENT_UNIX_SOCK); } - - ret = set_kconsumerd_sockets(); - if (ret < 0) { - goto error; - } } else { + home_path = get_home_dir(); + if (home_path == NULL) { + /* TODO: Add --socket PATH option */ + ERR("Can't get HOME directory for sockets creation."); + goto exit; + } + if (strlen(apps_unix_sock_path) == 0) { snprintf(apps_unix_sock_path, PATH_MAX, - DEFAULT_HOME_APPS_UNIX_SOCK, get_home_dir()); + DEFAULT_HOME_APPS_UNIX_SOCK, home_path); } /* Set the cli tool unix socket path */ if (strlen(client_unix_sock_path) == 0) { snprintf(client_unix_sock_path, PATH_MAX, - DEFAULT_HOME_CLIENT_UNIX_SOCK, get_home_dir()); + DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path); } } DBG("Client socket path %s", client_unix_sock_path); DBG("Application socket path %s", apps_unix_sock_path); - /* See if daemon already exist. If any of the two - * socket needed by the daemon are present, this test fails + /* + * See if daemon already exist. If any of the two socket needed by the + * daemon are present, this test fails. However, if the daemon is killed + * with a SIGKILL, those unix socket must be unlinked by hand. */ if ((ret = check_existing_daemon()) == 0) { ERR("Already running daemon.\n"); - /* We do not goto error because we must not - * cleanup() because a daemon is already running. + /* + * We do not goto error because we must not cleanup() because a daemon + * is already running. */ - exit(EXIT_FAILURE); + goto exit; + } + + /* After this point, we can safely call cleanup() so goto error is used */ + + /* + * These actions must be executed as root. We do that *after* setting up + * the sockets path because we MUST make the check for another daemon using + * those paths *before* trying to set the kernel consumer sockets and init + * kernel tracer. + */ + if (is_root) { + ret = set_kconsumerd_sockets(); + if (ret < 0) { + goto error; + } + + /* Setup kernel tracer */ + init_kernel_tracer(); + + /* Set ulimit for open files */ + set_ulimit(); } if (set_signal_handler() < 0) { @@ -1135,27 +2604,43 @@ int main(int argc, char **argv) ppid = getppid(); } + /* Setup the kernel pipe for waking up the kernel thread */ + if (create_kernel_poll_pipe() < 0) { + goto error; + } + + /* + * Get session list pointer. This pointer MUST NOT be free(). + * This list is statically declared in session.c + */ + session_list_ptr = get_session_list(); + while (1) { /* Create thread to manage the client socket */ - ret = pthread_create(&threads[0], NULL, thread_manage_clients, (void *) NULL); + ret = pthread_create(&client_thread, NULL, thread_manage_clients, (void *) NULL); if (ret != 0) { perror("pthread_create"); goto error; } /* Create thread to manage application socket */ - ret = pthread_create(&threads[1], NULL, thread_manage_apps, (void *) NULL); + ret = pthread_create(&apps_thread, NULL, thread_manage_apps, (void *) NULL); if (ret != 0) { perror("pthread_create"); goto error; } - for (i = 0; i < 2; i++) { - ret = pthread_join(threads[i], &status); - if (ret != 0) { - perror("pthread_join"); - goto error; - } + /* Create kernel thread to manage kernel event */ + ret = pthread_create(&kernel_thread, NULL, thread_manage_kernel, (void *) NULL); + if (ret != 0) { + perror("pthread_create"); + goto error; + } + + ret = pthread_join(client_thread, &status); + if (ret != 0) { + perror("pthread_join"); + goto error; } } @@ -1164,5 +2649,7 @@ int main(int argc, char **argv) error: cleanup(); + +exit: exit(EXIT_FAILURE); }