X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=ltt-sessiond%2Fmain.c;h=6fa89dd1e69ee000797584410aac26bc84aa8212;hp=a3584938134f3cdfb25d865c2d80a67aabacc550;hb=4b2221858653255be812d5a4e55c2ec05ec1819e;hpb=58a97671d5fa65f93126798ded9e5306e3555186 diff --git a/ltt-sessiond/main.c b/ltt-sessiond/main.c index a35849381..6fa89dd1e 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 @@ -21,6 +21,7 @@ #include #include #include +#include #include #include #include @@ -28,6 +29,7 @@ #include #include #include +#include #include #include #include @@ -47,16 +49,8 @@ #include "session.h" #include "traceable-app.h" #include "lttng-kconsumerd.h" -#include "libustctl.h" #include "utils.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. - */ - /* Const values */ const char default_home_dir[] = DEFAULT_HOME_DIR; const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP; @@ -66,6 +60,7 @@ const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE; /* Variables */ 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; @@ -73,6 +68,7 @@ static int opt_daemon; static int is_root; /* Set to 1 if the daemon is running as root */ 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 */ @@ -85,20 +81,57 @@ 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 */ /* - * teardown_kernel_session + * Pointer initialized before thread creation. + * + * 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. * - * Complete teardown of a kernel session. This free all data structure - * related to a kernel session and update counter. + * The lock is nested inside the structure: session_list_ptr->lock. Please use + * lock_session_list and unlock_session_list for lock acquisition. + */ +static struct ltt_session_list *session_list_ptr; + +/* + * Init quit pipe. + * + * Return -1 on error or 0 if all pipes are created. + */ +static int init_thread_quit_pipe(void) +{ + int ret; + + ret = pipe2(thread_quit_pipe, O_CLOEXEC); + if (ret < 0) { + perror("thread quit pipe"); + goto error; + } + +error: + return ret; +} + +/* + * 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) { @@ -107,41 +140,30 @@ static void teardown_kernel_session(struct ltt_session *session) trace_destroy_kernel_session(session->kernel_session); /* Extra precaution */ session->kernel_session = NULL; - /* Decrement session count */ - session->kern_session_count--; } } /* - * cleanup - * - * Cleanup the daemon on exit + * Cleanup the daemon */ static void cleanup() { int ret; char *cmd; - struct ltt_session *sess; + struct ltt_session *sess, *stmp; 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); + 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); /* */ /* Stopping all threads */ DBG("Terminating all threads"); - pthread_cancel(client_thread); - pthread_cancel(apps_thread); - if (kconsumerd_pid != 0) { - pthread_cancel(kconsumerd_thread); - } - - DBG("Unlinking all unix socket"); - unlink(client_unix_sock_path); - unlink(apps_unix_sock_path); - unlink(kconsumerd_err_unix_sock_path); + close(thread_quit_pipe[0]); + close(thread_quit_pipe[1]); DBG("Removing %s directory", LTTNG_RUNDIR); ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR); @@ -156,22 +178,28 @@ static void cleanup() } DBG("Cleaning up all session"); - /* Cleanup ALL session */ - cds_list_for_each_entry(sess, <t_session_list.head, list) { - teardown_kernel_session(sess); - // TODO complete session cleanup (including UST) + + /* Destroy session list mutex */ + if (session_list_ptr != NULL) { + pthread_mutex_destroy(&session_list_ptr->lock); + + /* 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) + } } + pthread_mutex_destroy(&kconsumerd_pid_mutex); + DBG("Closing kernel fd"); close(kernel_tracer_fd); } /* - * send_unix_sock + * Send data on a unix socket using the liblttsessiondcomm API. * - * Send data on a unix socket using the liblttsessiondcomm API. - * - * Return lttcomm error code. + * Return lttcomm error code. */ static int send_unix_sock(int sock, void *buf, size_t len) { @@ -184,43 +212,40 @@ static int send_unix_sock(int sock, void *buf, size_t len) } /* - * clean_command_ctx - * - * Free memory of a command context structure. + * Free memory of a command context structure. */ -static void clean_command_ctx(struct command_ctx *cmd_ctx) +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); + DBG("Clean command context structure"); + if (*cmd_ctx) { + if ((*cmd_ctx)->llm) { + free((*cmd_ctx)->llm); } - if (cmd_ctx->lsm) { - free(cmd_ctx->lsm); + if ((*cmd_ctx)->lsm) { + free((*cmd_ctx)->lsm); } - free(cmd_ctx); - cmd_ctx = NULL; + free(*cmd_ctx); + *cmd_ctx = NULL; } } /* - * send_kconsumerd_fds - * - * Send all stream fds of the kernel session to the consumer. + * Send all stream fds of kernel channel to the consumer. */ -static int send_kconsumerd_fds(int sock, struct ltt_kernel_session *session) +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 ltt_kernel_channel *chan; struct lttcomm_kconsumerd_header lkh; struct lttcomm_kconsumerd_msg lkm; - nb_fd = session->stream_count_global; + DBG("Sending fds of channel %s to kernel consumer", channel->channel->name); + + nb_fd = channel->stream_count; /* Setup header */ - lkh.payload_size = (nb_fd + 1) * sizeof(struct lttcomm_kconsumerd_msg); + lkh.payload_size = nb_fd * sizeof(struct lttcomm_kconsumerd_msg); lkh.cmd_type = ADD_STREAM; DBG("Sending kconsumerd header"); @@ -231,25 +256,11 @@ static int send_kconsumerd_fds(int sock, struct ltt_kernel_session *session) goto error; } - DBG("Sending metadata stream fd"); - - /* 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; - } - - cds_list_for_each_entry(chan, &session->channel_list.head, list) { - cds_list_for_each_entry(stream, &chan->stream_list.head, list) { + 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 = chan->channel->attr.subbuf_size; + 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); @@ -262,7 +273,7 @@ static int send_kconsumerd_fds(int sock, struct ltt_kernel_session *session) } } - DBG("Kconsumerd fds sent"); + DBG("Kconsumerd channel fds sent"); return 0; @@ -271,41 +282,64 @@ error: } /* - * create_trace_dir - * - * Create the trace output directory. + * Send all stream fds of the kernel session to the consumer. */ -static int create_trace_dir(struct ltt_kernel_session *session) +static int send_kconsumerd_fds(int sock, struct ltt_kernel_session *session) { 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; + } + + DBG("Sending metadata stream fd"); + + 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; + } + } - /* Create all channel directories */ cds_list_for_each_entry(chan, &session->channel_list.head, list) { - DBG("Creating trace directory at %s", chan->pathname); - ret = mkdir_recursive(chan->pathname, S_IRWXU | S_IRWXG ); + ret = send_kconsumerd_channel_fds(sock, chan); if (ret < 0) { - if (ret != EEXIST) { - ERR("Trace directory creation error"); - goto error; - } + goto error; } } + 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) { @@ -328,15 +362,14 @@ static int ust_connect_app(pid_t 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) { @@ -362,13 +395,11 @@ 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) { @@ -385,7 +416,7 @@ 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; + cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid; cmd_ctx->llm->data_size = size; cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size; @@ -397,15 +428,220 @@ error: } /* - * thread_manage_kconsumerd + * 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 update_kernel_pollfd(void) +{ + 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("Resizing kernel_pollfd to size %d", nb_fd); + + kernel_pollfd = realloc(kernel_pollfd, nb_fd * sizeof(struct pollfd)); + if (kernel_pollfd == NULL) { + perror("malloc kernel_pollfd"); + 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. * - * This thread manage the kconsumerd error sent - * back to the session daemon. + * 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, ret; + int sock = 0, ret; enum lttcomm_return_code code; + struct pollfd pollfd[2]; DBG("[thread] Manage kconsumerd started"); @@ -414,6 +650,28 @@ static void *thread_manage_kconsumerd(void *data) 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; @@ -451,19 +709,31 @@ static void *thread_manage_kconsumerd(void *data) ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code)); error: - kconsumerd_pid = 0; 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; } /* - * thread_manage_apps - * * This thread manage the application socket communication */ static void *thread_manage_apps(void *data) { - int sock, ret; + 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 @@ -482,18 +752,41 @@ static void *thread_manage_apps(void *data) 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"); - /* Blocking call, waiting for transmission */ + + /* 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 + /* + * 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); @@ -519,15 +812,21 @@ static void *thread_manage_apps(void *data) } error: + DBG("Apps thread dying"); + if (apps_sock) { + close(apps_sock); + } + if (sock) { + close(sock); + } + unlink(apps_unix_sock_path); return NULL; } /* - * spawn_kconsumerd_thread - * - * Start the thread_manage_kconsumerd. This must be done after a kconsumerd - * exec or it will fails. + * Start the thread_manage_kconsumerd. This must be done after a kconsumerd + * exec or it will fails. */ static int spawn_kconsumerd_thread(void) { @@ -558,20 +857,15 @@ error: } /* - * spawn_kconsumerd - * - * Fork and exec a kernel consumer daemon (kconsumerd). - * - * NOTE: It is very important to fork a kconsumerd BEFORE opening any kernel - * file descriptor using the libkernelctl or kernel-ctl functions. So, a - * kernel consumer MUST only be spawned before creating a kernel session. + * Fork and exec a kernel consumer daemon (kconsumerd). * - * Return pid if successful else -1. + * Return pid if successful else -1. */ static pid_t spawn_kconsumerd(void) { int ret; pid_t pid; + const char *verbosity; DBG("Spawning kconsumerd"); @@ -580,7 +874,12 @@ static pid_t spawn_kconsumerd(void) /* * Exec kconsumerd. */ - execlp("kconsumerd", "kconsumerd", "--verbose", NULL); + 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"); } @@ -599,9 +898,7 @@ error: } /* - * start_kconsumerd - * - * Spawn the kconsumerd daemon and session daemon thread. + * Spawn the kconsumerd daemon and session daemon thread. */ static int start_kconsumerd(void) { @@ -609,6 +906,7 @@ static int start_kconsumerd(void) pthread_mutex_lock(&kconsumerd_pid_mutex); if (kconsumerd_pid != 0) { + pthread_mutex_unlock(&kconsumerd_pid_mutex); goto end; } @@ -634,7 +932,6 @@ static int start_kconsumerd(void) } end: - pthread_mutex_unlock(&kconsumerd_pid_mutex); return 0; error: @@ -642,43 +939,146 @@ error: } /* - * init_kernel_tracer - * - * Setup necessary data for kernel tracer action. + * modprobe_kernel_modules */ -static void init_kernel_tracer(void) +static int modprobe_kernel_modules(void) { - /* Set the global kernel tracer fd */ - kernel_tracer_fd = open(DEFAULT_KERNEL_TRACER_PATH, O_RDWR); - if (kernel_tracer_fd < 0) { - WARN("No kernel tracer available"); - kernel_tracer_fd = 0; + 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++; } - DBG("Kernel tracer fd %d", kernel_tracer_fd); +error: + return ret; } /* - * start_kernel_trace - * - * Start tracing by creating trace directory and sending FDs to the kernel - * consumer. + * mount_debugfs */ -static int start_kernel_trace(struct ltt_kernel_session *session) +static int mount_debugfs(char *path) { int ret; + char *type = "debugfs"; - /* Create trace directory */ - ret = create_trace_dir(session); + ret = mkdir_recursive(path, S_IRWXU | S_IRWXG); if (ret < 0) { - if (ret == -EEXIST) { - ret = LTTCOMM_KERN_DIR_EXIST; - } else { - ret = LTTCOMM_KERN_DIR_FAIL; + 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) { @@ -695,11 +1095,25 @@ error: } /* - * init_default_channel - * - * Allocate a channel structure and fill it. + * Notify kernel thread to update it's pollfd. */ -static struct lttng_channel *init_default_channel(void) +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; @@ -709,8 +1123,8 @@ static struct lttng_channel *init_default_channel(void) goto error; } - if (snprintf(chan->name, NAME_MAX, DEFAULT_CHANNEL_NAME) < 0) { - perror("snprintf defautl channel name"); + if (snprintf(chan->name, NAME_MAX, "%s", name) < 0) { + perror("snprintf channel name"); return NULL; } @@ -726,53 +1140,128 @@ error: } /* - * create_kernel_session - * - * Create a kernel tracer session then create the default channel. + * 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++; + } +} + +/* + * Fill lttng_channel array of all channels. */ -static int create_kernel_session(struct ltt_session *session) +static void list_lttng_channels(struct ltt_session *session, + struct lttng_channel *channels) { - int ret; - struct lttng_channel *chan; + int i = 0; + struct ltt_kernel_channel *kchan; - DBG("Creating kernel session"); - - ret = kernel_create_session(session, kernel_tracer_fd); - if (ret < 0) { - ret = LTTCOMM_KERN_SESS_FAIL; - goto error; - } + DBG("Listing channels for session %s", session->name); - chan = init_default_channel(); - if (chan == NULL) { - ret = LTTCOMM_FATAL; - goto error; + /* Kernel channels */ + if (session->kernel_session != NULL) { + cds_list_for_each_entry(kchan, &session->kernel_session->channel_list.head, list) { + /* Copy lttng_channel struct to array */ + memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel)); + channels[i].enabled = kchan->enabled; + i++; + } } - DBG("Creating default kernel channel %s", DEFAULT_CHANNEL_NAME); + /* TODO: Missing UST listing */ +} - ret = kernel_create_channel(session->kernel_session, chan, session->path); - if (ret < 0) { - ret = LTTCOMM_KERN_CHAN_FAIL; - goto error; +/* + * Fill lttng_event array of all events in the channel. + */ +static void list_lttng_events(struct ltt_kernel_channel *kchan, + struct lttng_event *events) +{ + /* + * TODO: This is ONLY kernel. Need UST support. + */ + int i = 0; + struct ltt_kernel_event *event; + + DBG("Listing events for channel %s", kchan->channel->name); + + /* Kernel channels */ + cds_list_for_each_entry(event, &kchan->events_list.head , list) { + strncpy(events[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN); + events[i].enabled = event->enabled; + switch (event->event->instrumentation) { + case LTTNG_KERNEL_TRACEPOINT: + events[i].type = LTTNG_EVENT_TRACEPOINT; + break; + case LTTNG_KERNEL_KPROBE: + case LTTNG_KERNEL_KRETPROBE: + events[i].type = LTTNG_EVENT_PROBE; + memcpy(&events[i].attr.probe, &event->event->u.kprobe, + sizeof(struct lttng_kernel_kprobe)); + break; + case LTTNG_KERNEL_FUNCTION: + events[i].type = LTTNG_EVENT_FUNCTION; + memcpy(&events[i].attr.ftrace, &event->event->u.ftrace, + sizeof(struct lttng_kernel_function)); + break; + } + i++; } - -error: - return ret; } /* - * 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. + * 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; + int ret = LTTCOMM_OK; DBG("Processing client command %d", cmd_ctx->lsm->cmd_type); @@ -780,9 +1269,7 @@ static int process_client_msg(struct command_ctx *cmd_ctx) 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); @@ -795,6 +1282,9 @@ static int process_client_msg(struct command_ctx *cmd_ctx) ret = LTTCOMM_SELECT_SESS; } goto error; + } else { + /* Acquire lock for the session */ + lock_session(cmd_ctx->session); } break; } @@ -804,7 +1294,6 @@ static int process_client_msg(struct command_ctx *cmd_ctx) */ switch (cmd_ctx->lsm->cmd_type) { case LTTNG_KERNEL_ADD_CONTEXT: - case LTTNG_KERNEL_CREATE_CHANNEL: case LTTNG_KERNEL_DISABLE_ALL_EVENT: case LTTNG_KERNEL_DISABLE_CHANNEL: case LTTNG_KERNEL_DISABLE_EVENT: @@ -841,6 +1330,7 @@ static int process_client_msg(struct command_ctx *cmd_ctx) } } +#ifdef DISABLED /* Connect to ust apps if available pid */ if (cmd_ctx->lsm->pid > 0) { /* Connect to app using ustctl API */ @@ -850,6 +1340,7 @@ static int process_client_msg(struct command_ctx *cmd_ctx) goto error; } } +#endif /* DISABLED */ /* Process by command type */ switch (cmd_ctx->lsm->cmd_type) { @@ -858,6 +1349,7 @@ static int process_client_msg(struct command_ctx *cmd_ctx) 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); @@ -870,22 +1362,29 @@ static int process_client_msg(struct command_ctx *cmd_ctx) 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, - &cmd_ctx->lsm->u.context.ctx); + ret = kernel_add_channel_context(chan, &ctx); if (ret < 0) { - continue; + 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, - &cmd_ctx->lsm->u.context.ctx); + ret = kernel_add_event_context(event, &ctx); if (ret < 0) { ret = LTTCOMM_KERN_CONTEXT_FAIL; goto error; @@ -904,8 +1403,7 @@ static int process_client_msg(struct command_ctx *cmd_ctx) } if (no_event) { - ret = kernel_add_channel_context(chan, - &cmd_ctx->lsm->u.context.ctx); + ret = kernel_add_channel_context(chan, &ctx); if (ret < 0) { ret = LTTCOMM_KERN_CONTEXT_FAIL; goto error; @@ -913,8 +1411,7 @@ static int process_client_msg(struct command_ctx *cmd_ctx) } else { event = get_kernel_event_by_name(cmd_ctx->lsm->u.context.event_name, chan); if (event != NULL) { - ret = kernel_add_event_context(event, - &cmd_ctx->lsm->u.context.ctx); + ret = kernel_add_event_context(event, &ctx); if (ret < 0) { ret = LTTCOMM_KERN_CONTEXT_FAIL; goto error; @@ -931,27 +1428,6 @@ static int process_client_msg(struct command_ctx *cmd_ctx) ret = LTTCOMM_OK; break; } - case LTTNG_KERNEL_CREATE_CHANNEL: - { - /* Setup lttng message with no payload */ - ret = setup_lttng_msg(cmd_ctx, 0); - if (ret < 0) { - goto setup_error; - } - - /* Kernel tracer */ - 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; - } - - ret = LTTCOMM_OK; - break; - } case LTTNG_KERNEL_DISABLE_CHANNEL: { struct ltt_kernel_channel *chan; @@ -1062,8 +1538,22 @@ static int process_client_msg(struct command_ctx *cmd_ctx) chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.enable.channel_name, cmd_ctx->session->kernel_session); if (chan == NULL) { - ret = LTTCOMM_KERN_CHAN_NOT_FOUND; - goto error; + /* 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) { @@ -1080,8 +1570,10 @@ static int process_client_msg(struct command_ctx *cmd_ctx) } case LTTNG_KERNEL_ENABLE_EVENT: { - struct ltt_kernel_channel *chan; + 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); @@ -1089,22 +1581,42 @@ static int process_client_msg(struct command_ctx *cmd_ctx) goto setup_error; } - chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.enable.channel_name, - cmd_ctx->session->kernel_session); - if (chan == NULL) { - ret = LTTCOMM_KERN_CHAN_NOT_FOUND; - goto 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; + } - ev = get_kernel_event_by_name(cmd_ctx->lsm->u.enable.event.name, chan); + 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, chan->channel->name); - ret = kernel_create_event(&cmd_ctx->lsm->u.enable.event, chan); + 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, chan->channel->name); + 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) { @@ -1118,11 +1630,12 @@ static int process_client_msg(struct command_ctx *cmd_ctx) } case LTTNG_KERNEL_ENABLE_ALL_EVENT: { - int pos, size; - char *event_list, *event, *ptr; - struct ltt_kernel_channel *chan; + int size, i; + char *channel_name; + struct ltt_kernel_channel *kchan; struct ltt_kernel_event *ev; - struct lttng_event ev_attr; + struct lttng_event *event_list; + struct lttng_channel *chan; /* Setup lttng message with no payload */ ret = setup_lttng_msg(cmd_ctx, 0); @@ -1132,17 +1645,33 @@ static int process_client_msg(struct command_ctx *cmd_ctx) DBG("Enabling all kernel event"); - chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.enable.channel_name, - cmd_ctx->session->kernel_session); - if (chan == NULL) { - ret = LTTCOMM_KERN_CHAN_NOT_FOUND; - goto 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); /* For each event in the kernel session */ - cds_list_for_each_entry(ev, &chan->events_list.head, list) { + cds_list_for_each_entry(ev, &kchan->events_list.head, list) { DBG("Enabling kernel event %s for channel %s.", - ev->event->name, chan->channel->name); + ev->event->name, channel_name); ret = kernel_enable_event(ev); if (ret < 0) { continue; @@ -1155,23 +1684,17 @@ static int process_client_msg(struct command_ctx *cmd_ctx) goto error; } - ptr = event_list; - while ((size = sscanf(ptr, "event { name = %m[^;]; };%n\n", &event, &pos)) == 1) { - ev = get_kernel_event_by_name(event, chan); + for (i = 0; i < size; i++) { + ev = get_kernel_event_by_name(event_list[i].name, kchan); if (ev == NULL) { - strncpy(ev_attr.name, event, LTTNG_SYM_NAME_LEN); /* Default event type for enable all */ - ev_attr.type = LTTNG_EVENT_TRACEPOINTS; + event_list[i].type = LTTNG_EVENT_TRACEPOINT; /* Enable each single tracepoint event */ - ret = kernel_create_event(&ev_attr, chan); + ret = kernel_create_event(&event_list[i], kchan); if (ret < 0) { /* Ignore error here and continue */ } } - - /* Move pointer to the next line */ - ptr += pos + 1; - free(event); } free(event_list); @@ -1183,12 +1706,12 @@ static int process_client_msg(struct command_ctx *cmd_ctx) } case LTTNG_KERNEL_LIST_EVENTS: { - char *event_list; + struct lttng_event *events; ssize_t size = 0; DBG("Listing kernel events"); - size = kernel_list_events(kernel_tracer_fd, &event_list); + size = kernel_list_events(kernel_tracer_fd, &events); if (size < 0) { ret = LTTCOMM_KERN_LIST_FAIL; goto error; @@ -1198,15 +1721,16 @@ static int process_client_msg(struct command_ctx *cmd_ctx) * 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); + ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * size); if (ret < 0) { goto setup_error; } /* Copy event list into message payload */ - memcpy(cmd_ctx->llm->payload, event_list, size); + memcpy(cmd_ctx->llm->payload, events, + sizeof(struct lttng_event) * size); - free(event_list); + free(events); ret = LTTCOMM_OK; break; @@ -1361,112 +1885,159 @@ static int process_client_msg(struct command_ctx *cmd_ctx) 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_FATAL; + goto error; + } + ret = LTTCOMM_OK; break; } /* - case LTTNG_LIST_TRACES: + case UST_CREATE_TRACE: { - unsigned int trace_count; + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; + } - trace_count = get_trace_count_per_session(cmd_ctx->session); - if (trace_count == 0) { - ret = LTTCOMM_NO_TRACE; + ret = ust_create_trace(cmd_ctx); + if (ret < 0) { goto error; } - - ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_trace) * trace_count); + break; + } + case UST_START_TRACE: + { + ret = setup_lttng_msg(cmd_ctx, 0); if (ret < 0) { goto setup_error; } - get_traces_per_session(cmd_ctx->session, - (struct lttng_trace *)(cmd_ctx->llm->payload)); - - ret = LTTCOMM_OK; + ret = ust_start_trace(cmd_ctx); + if (ret < 0) { + goto setup_error; + } break; } - */ - /* - case UST_CREATE_TRACE: + case UST_STOP_TRACE: { ret = setup_lttng_msg(cmd_ctx, 0); if (ret < 0) { goto setup_error; } - ret = ust_create_trace(cmd_ctx); + ret = ust_stop_trace(cmd_ctx); if (ret < 0) { - goto error; + goto setup_error; } break; } */ - case LTTNG_LIST_TRACEABLE_APPS: + case LTTNG_LIST_DOMAINS: { - unsigned int app_count; + size_t nb_dom = 0; - app_count = get_app_count(); - DBG("Traceable application count : %d", app_count); - if (app_count == 0) { - ret = LTTCOMM_NO_APPS; - goto error; + if (cmd_ctx->session->kernel_session != NULL) { + nb_dom++; } - ret = setup_lttng_msg(cmd_ctx, sizeof(pid_t) * app_count); + nb_dom += cmd_ctx->session->ust_trace_count; + + ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_domain) * nb_dom); if (ret < 0) { goto setup_error; } - get_app_list_pids((pid_t *)(cmd_ctx->llm->payload)); + ((struct lttng_domain *)(cmd_ctx->llm->payload))[0].type = + LTTNG_DOMAIN_KERNEL; + /* TODO: User-space tracer domain support */ ret = LTTCOMM_OK; break; } - /* - case UST_START_TRACE: + case LTTNG_LIST_CHANNELS: { - ret = setup_lttng_msg(cmd_ctx, 0); - if (ret < 0) { - goto setup_error; + /* + * TODO: Only kernel channels are listed here. UST listing + * is needed on lttng-ust 2.0 release. + */ + size_t nb_chan = 0; + if (cmd_ctx->session->kernel_session != NULL) { + nb_chan += cmd_ctx->session->kernel_session->channel_count; } - ret = ust_start_trace(cmd_ctx); + ret = setup_lttng_msg(cmd_ctx, + sizeof(struct lttng_channel) * nb_chan); if (ret < 0) { goto setup_error; } + + list_lttng_channels(cmd_ctx->session, + (struct lttng_channel *)(cmd_ctx->llm->payload)); + + ret = LTTCOMM_OK; break; } - case UST_STOP_TRACE: + case LTTNG_LIST_EVENTS: { - ret = setup_lttng_msg(cmd_ctx, 0); - if (ret < 0) { - goto setup_error; + /* + * TODO: Only kernel events are listed here. UST listing + * is needed on lttng-ust 2.0 release. + */ + size_t nb_event = 0; + struct ltt_kernel_channel *kchan = NULL; + + if (cmd_ctx->session->kernel_session != NULL) { + kchan = get_kernel_channel_by_name(cmd_ctx->lsm->u.list.channel_name, + cmd_ctx->session->kernel_session); + if (kchan == NULL) { + ret = LTTCOMM_KERN_CHAN_NOT_FOUND; + goto error; + } + nb_event += kchan->event_count; } - ret = ust_stop_trace(cmd_ctx); + ret = setup_lttng_msg(cmd_ctx, + sizeof(struct lttng_event) * nb_event); if (ret < 0) { goto setup_error; } + + DBG("Listing events (%ld events)", nb_event); + + list_lttng_events(kchan, + (struct lttng_event *)(cmd_ctx->llm->payload)); + + ret = LTTCOMM_OK; break; } - */ case LTTNG_LIST_SESSIONS: { - unsigned int session_count; + lock_session_list(); - session_count = get_session_count(); - if (session_count == 0) { + if (session_list_ptr->count == 0) { ret = LTTCOMM_NO_SESSION; + unlock_session_list(); 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) { + unlock_session_list(); 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; @@ -1485,6 +2056,10 @@ 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: @@ -1498,19 +2073,21 @@ error: cmd_ctx->llm->ret_code = ret; setup_error: + if (cmd_ctx->session) { + unlock_session(cmd_ctx->session); + } return ret; } /* - * thread_manage_clients - * - * This thread manage all clients request using the unix - * client socket for communication. + * This thread manage all clients request using the unix client socket for + * communication. */ static void *thread_manage_clients(void *data) { - int sock, ret; - struct command_ctx *cmd_ctx; + int sock = 0, ret; + struct command_ctx *cmd_ctx = NULL; + struct pollfd pollfd[2]; DBG("[thread] Manage client started"); @@ -1519,6 +2096,13 @@ static void *thread_manage_clients(void *data) 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. */ @@ -1527,8 +2111,23 @@ static void *thread_manage_clients(void *data) } while (1) { - /* Blocking call, waiting for transmission */ 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; @@ -1566,7 +2165,7 @@ static void *thread_manage_clients(void *data) /* 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); + clean_command_ctx(&cmd_ctx); continue; } @@ -1577,13 +2176,24 @@ static void *thread_manage_clients(void *data) ERR("Failed to send data back to client"); } - clean_command_ctx(cmd_ctx); + 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; } @@ -1674,7 +2284,8 @@ 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. @@ -1687,9 +2298,7 @@ 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). */ @@ -1738,10 +2347,7 @@ 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() { @@ -1756,12 +2362,10 @@ static int check_existing_daemon() } /* - * 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) { @@ -1774,8 +2378,13 @@ 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; } @@ -1807,10 +2416,15 @@ 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) { @@ -1831,10 +2445,8 @@ 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) { @@ -1878,9 +2490,7 @@ error: } /* - * sighandler - * - * Signal handler for the daemon + * Signal handler for the daemon */ static void sighandler(int sig) { @@ -1904,9 +2514,7 @@ static void sighandler(int sig) } /* - * set_signal_handler - * - * Setup signal handler for : + * Setup signal handler for : * SIGINT, SIGTERM, SIGPIPE */ static int set_signal_handler(void) @@ -1944,16 +2552,15 @@ static int set_signal_handler(void) } /* - * set_ulimit - * - * Set open files limit to unlimited. This daemon can open a large number of - * file descriptors in order to consumer multiple kernel traces. + * 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 set_ulimit(void) { int ret; struct rlimit lim; + /* The kernel does not allowed an infinite limit for open files */ lim.rlim_cur = 65535; lim.rlim_max = 65535; @@ -1972,10 +2579,15 @@ int main(int argc, char **argv) void *status; 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 */ @@ -1983,18 +2595,17 @@ 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) { @@ -2006,23 +2617,12 @@ 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; - } - - /* Setup kernel tracer */ - init_kernel_tracer(); - - /* Set ulimit for open files */ - set_ulimit(); } else { home_path = get_home_dir(); if (home_path == NULL) { - ERR("Can't get HOME directory for sockets creation.\n \ - Please specify --socket PATH."); - goto error; + /* TODO: Add --socket PATH option */ + ERR("Can't get HOME directory for sockets creation."); + goto exit; } if (strlen(apps_unix_sock_path) == 0) { @@ -2040,15 +2640,39 @@ int main(int argc, char **argv) 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) { @@ -2070,6 +2694,17 @@ 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(&client_thread, NULL, thread_manage_clients, (void *) NULL); @@ -2085,6 +2720,13 @@ int main(int argc, char **argv) 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"); @@ -2097,5 +2739,7 @@ int main(int argc, char **argv) error: cleanup(); + +exit: exit(EXIT_FAILURE); }