+ * 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;
+ char modprobe[256];
+
+ for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
+ ret = snprintf(modprobe, sizeof(modprobe),
+ "/sbin/modprobe %s%s",
+ kernel_modules_list[i].required ? "" : "--quiet ",
+ kernel_modules_list[i].name);
+ if (ret < 0) {
+ perror("snprintf modprobe");
+ goto error;
+ }
+ modprobe[sizeof(modprobe) - 1] = '\0';
+ ret = system(modprobe);
+ if (ret == -1) {
+ ERR("Unable to launch modprobe for module %s",
+ kernel_modules_list[i].name);
+ } else if (kernel_modules_list[i].required
+ && WEXITSTATUS(ret) != 0) {
+ ERR("Unable to load module %s",
+ kernel_modules_list[i].name);
+ } else {
+ DBG("Modprobe successfully %s",
+ kernel_modules_list[i].name);
+ }
+ }
+
+error:
+ return ret;
+}
+
+/*
+ * modprobe_remove_kernel_modules
+ * Remove modules in reverse load order.
+ */
+static int modprobe_remove_kernel_modules(void)
+{
+ int ret = 0, i;
+ char modprobe[256];
+
+ for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
+ ret = snprintf(modprobe, sizeof(modprobe),
+ "/sbin/modprobe --remove --quiet %s",
+ kernel_modules_list[i].name);
+ if (ret < 0) {
+ perror("snprintf modprobe --remove");
+ goto error;
+ }
+ modprobe[sizeof(modprobe) - 1] = '\0';
+ ret = system(modprobe);
+ if (ret == -1) {
+ ERR("Unable to launch modprobe --remove for module %s",
+ kernel_modules_list[i].name);
+ } else if (kernel_modules_list[i].required
+ && WEXITSTATUS(ret) != 0) {
+ ERR("Unable to remove module %s",
+ kernel_modules_list[i].name);
+ } else {
+ DBG("Modprobe removal successful %s",
+ kernel_modules_list[i].name);
+ }
+ }
+
+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 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++;
+ }
+}
+
+/*
+ * Fill lttng_channel array of all channels.
+ */
+static void list_lttng_channels(struct ltt_session *session,
+ struct lttng_channel *channels)
+{
+ int i = 0;
+ struct ltt_kernel_channel *kchan;
+
+ DBG("Listing channels for session %s", session->name);
+
+ /* 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++;
+ }
+ }
+
+ /* TODO: Missing UST listing */
+}
+
+/*
+ * 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++;
+ }
+}
+
+/*
+ * 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_TRACEPOINTS:
+ 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 domain type for specifif "pre-action".
+ */
+ switch (cmd_ctx->lsm->domain.type) {
+ case LTTNG_DOMAIN_KERNEL:
+ /* 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_LIST_TRACEPOINTS &&
+ 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;
+ }
+ }
+ }
+ break;
+ default:
+ break;
+ }
+
+ /* Process by command type */
+ switch (cmd_ctx->lsm->cmd_type) {
+ case LTTNG_ADD_CONTEXT:
+ {
+ struct lttng_kernel_context kctx;
+
+ /* Setup lttng message with no payload */
+ ret = setup_lttng_msg(cmd_ctx, 0);
+ if (ret < 0) {
+ goto setup_error;
+ }
+
+ switch (cmd_ctx->lsm->domain.type) {
+ case LTTNG_DOMAIN_KERNEL:
+ /* Create Kernel context */
+ kctx.ctx = cmd_ctx->lsm->u.context.ctx.ctx;
+ kctx.u.perf_counter.type = cmd_ctx->lsm->u.context.ctx.u.perf_counter.type;
+ kctx.u.perf_counter.config = cmd_ctx->lsm->u.context.ctx.u.perf_counter.config;
+ strncpy(kctx.u.perf_counter.name,
+ cmd_ctx->lsm->u.context.ctx.u.perf_counter.name,
+ LTTNG_SYMBOL_NAME_LEN);
+
+ /* Add kernel context to kernel tracer. See context.c */
+ ret = add_kernel_context(cmd_ctx->session->kernel_session, &kctx,
+ cmd_ctx->lsm->u.context.event_name,
+ cmd_ctx->lsm->u.context.channel_name);
+ if (ret != LTTCOMM_OK) {
+ goto error;
+ }
+ break;
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+ break;
+ }
+ case LTTNG_DISABLE_CHANNEL:
+ {
+ struct ltt_kernel_channel *kchan;
+
+ /* Setup lttng message with no payload */
+ ret = setup_lttng_msg(cmd_ctx, 0);
+ if (ret < 0) {
+ goto setup_error;
+ }
+
+ switch (cmd_ctx->lsm->domain.type) {
+ case LTTNG_DOMAIN_KERNEL:
+ kchan = get_kernel_channel_by_name(cmd_ctx->lsm->u.disable.channel_name,
+ cmd_ctx->session->kernel_session);
+ if (kchan == NULL) {
+ ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
+ goto error;
+ } else if (kchan->enabled == 1) {
+ ret = kernel_disable_channel(kchan);
+ if (ret < 0) {
+ if (ret != EEXIST) {
+ ret = LTTCOMM_KERN_CHAN_DISABLE_FAIL;
+ }
+ goto error;
+ }
+ }
+ kernel_wait_quiescent(kernel_tracer_fd);
+ break;
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+ break;
+ }
+ case LTTNG_DISABLE_EVENT:
+ {
+ struct ltt_kernel_channel *kchan;
+ struct ltt_kernel_event *kevent;
+
+ /* Setup lttng message with no payload */
+ ret = setup_lttng_msg(cmd_ctx, 0);
+ if (ret < 0) {
+ goto setup_error;
+ }
+
+ switch (cmd_ctx->lsm->domain.type) {
+ case LTTNG_DOMAIN_KERNEL:
+ kchan = get_kernel_channel_by_name(cmd_ctx->lsm->u.disable.channel_name,
+ cmd_ctx->session->kernel_session);
+ if (kchan == NULL) {
+ ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
+ goto error;
+ }
+
+ kevent = get_kernel_event_by_name(cmd_ctx->lsm->u.disable.name, kchan);
+ if (kevent != NULL) {
+ DBG("Disabling kernel event %s for channel %s.", kevent->event->name,
+ kchan->channel->name);
+ ret = kernel_disable_event(kevent);
+ if (ret < 0) {
+ ret = LTTCOMM_KERN_ENABLE_FAIL;
+ goto error;
+ }
+ }
+
+ kernel_wait_quiescent(kernel_tracer_fd);
+ break;
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+ break;
+ }
+ case LTTNG_DISABLE_ALL_EVENT:
+ {
+ struct ltt_kernel_channel *kchan;
+ struct ltt_kernel_event *kevent;
+
+ /* Setup lttng message with no payload */
+ ret = setup_lttng_msg(cmd_ctx, 0);
+ if (ret < 0) {
+ goto setup_error;
+ }
+
+ switch (cmd_ctx->lsm->domain.type) {
+ case LTTNG_DOMAIN_KERNEL:
+ DBG("Disabling all enabled kernel events");
+ kchan = get_kernel_channel_by_name(cmd_ctx->lsm->u.disable.channel_name,
+ cmd_ctx->session->kernel_session);
+ if (kchan == NULL) {
+ ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
+ goto error;
+ }
+
+ /* For each event in the kernel session */
+ cds_list_for_each_entry(kevent, &kchan->events_list.head, list) {
+ DBG("Disabling kernel event %s for channel %s.",
+ kevent->event->name, kchan->channel->name);
+ ret = kernel_disable_event(kevent);
+ if (ret < 0) {
+ continue;
+ }
+ }
+
+ /* Quiescent wait after event disable */
+ kernel_wait_quiescent(kernel_tracer_fd);
+ break;
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+ break;
+ }
+ case LTTNG_ENABLE_CHANNEL:
+ {
+ struct ltt_kernel_channel *kchan;
+
+ /* Setup lttng message with no payload */
+ ret = setup_lttng_msg(cmd_ctx, 0);
+ if (ret < 0) {
+ goto setup_error;
+ }
+
+ switch (cmd_ctx->lsm->domain.type) {
+ case LTTNG_DOMAIN_KERNEL:
+ kchan = get_kernel_channel_by_name(cmd_ctx->lsm->u.enable.channel_name,
+ cmd_ctx->session->kernel_session);
+ if (kchan == 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 (kchan->enabled == 0) {
+ ret = kernel_enable_channel(kchan);
+ if (ret < 0) {
+ if (ret != EEXIST) {
+ ret = LTTCOMM_KERN_CHAN_ENABLE_FAIL;
+ }
+ goto error;
+ }
+ }
+
+ kernel_wait_quiescent(kernel_tracer_fd);
+ break;
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+ break;
+ }
+ case LTTNG_ENABLE_EVENT:
+ {
+ char *channel_name;
+ struct ltt_kernel_channel *kchan;
+ struct ltt_kernel_event *kevent;
+ 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;
+
+ switch (cmd_ctx->lsm->domain.type) {
+ case LTTNG_DOMAIN_KERNEL:
+ 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);
+
+ kevent = get_kernel_event_by_name(cmd_ctx->lsm->u.enable.event.name, kchan);
+ if (kevent == 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.",
+ kevent->event->name, channel_name);
+ ret = kernel_enable_event(kevent);
+ 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);
+ break;
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+ ret = LTTCOMM_OK;
+ break;
+ }
+ case LTTNG_ENABLE_ALL_EVENT:
+ {
+ int size, i;
+ char *channel_name;
+ struct ltt_kernel_channel *kchan;
+ struct ltt_kernel_event *kevent;
+ struct lttng_event *event_list;
+ 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;
+
+ switch (cmd_ctx->lsm->domain.type) {
+ case LTTNG_DOMAIN_KERNEL:
+ 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(kevent, &kchan->events_list.head, list) {
+ DBG("Enabling kernel event %s for channel %s.",
+ kevent->event->name, channel_name);
+ ret = kernel_enable_event(kevent);
+ if (ret < 0) {
+ continue;
+ }
+ }
+
+ size = kernel_list_events(kernel_tracer_fd, &event_list);
+ if (size < 0) {
+ ret = LTTCOMM_KERN_LIST_FAIL;
+ goto error;
+ }
+
+ for (i = 0; i < size; i++) {
+ kevent = get_kernel_event_by_name(event_list[i].name, kchan);
+ if (kevent == NULL) {
+ /* Default event type for enable all */
+ event_list[i].type = LTTNG_EVENT_TRACEPOINT;
+ /* Enable each single tracepoint event */
+ ret = kernel_create_event(&event_list[i], kchan);
+ if (ret < 0) {
+ /* Ignore error here and continue */
+ }
+ }
+ }
+
+ free(event_list);
+
+ /* Quiescent wait after event enable */
+ kernel_wait_quiescent(kernel_tracer_fd);
+ break;
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+ break;
+ }
+ case LTTNG_LIST_TRACEPOINTS:
+ {
+ struct lttng_event *events;
+ ssize_t nb_events = 0;
+
+ switch (cmd_ctx->lsm->domain.type) {
+ case LTTNG_DOMAIN_KERNEL:
+ DBG("Listing kernel events");
+ nb_events = kernel_list_events(kernel_tracer_fd, &events);
+ if (nb_events < 0) {
+ ret = LTTCOMM_KERN_LIST_FAIL;
+ goto error;
+ }
+ break;
+ default:
+ /* TODO: Userspace listing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ break;
+ }
+
+ /*
+ * 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, sizeof(struct lttng_event) * nb_events);
+ if (ret < 0) {
+ free(events);
+ goto setup_error;
+ }
+
+ /* Copy event list into message payload */
+ memcpy(cmd_ctx->llm->payload, events,
+ sizeof(struct lttng_event) * nb_events);
+
+ free(events);
+
+ 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;
+ }
+ case LTTNG_CREATE_SESSION:
+ {
+ /* Setup lttng message with no payload */
+ ret = setup_lttng_msg(cmd_ctx, 0);
+ if (ret < 0) {
+ goto setup_error;
+ }
+
+ ret = create_session(cmd_ctx->lsm->session.name, cmd_ctx->lsm->session.path);
+ if (ret < 0) {
+ if (ret == -EEXIST) {
+ ret = LTTCOMM_EXIST_SESS;
+ } else {
+ ret = LTTCOMM_FATAL;
+ }
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+ break;
+ }
+ case LTTNG_DESTROY_SESSION:
+ {
+ /* Setup lttng message with no payload */
+ ret = setup_lttng_msg(cmd_ctx, 0);
+ if (ret < 0) {
+ goto setup_error;
+ }
+
+ /* 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_FATAL;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+ break;
+ }
+ case LTTNG_LIST_DOMAINS:
+ {
+ size_t nb_dom = 0;
+
+ if (cmd_ctx->session->kernel_session != NULL) {
+ nb_dom++;
+ }
+
+ 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;
+ }
+
+ ((struct lttng_domain *)(cmd_ctx->llm->payload))[0].type =
+ LTTNG_DOMAIN_KERNEL;
+
+ /* TODO: User-space tracer domain support */
+ ret = LTTCOMM_OK;
+ break;
+ }
+ case LTTNG_LIST_CHANNELS:
+ {
+ /*
+ * 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 = 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 LTTNG_LIST_EVENTS:
+ {
+ /*
+ * 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 = 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:
+ {
+ lock_session_list();
+
+ 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_list_ptr->count);
+ if (ret < 0) {
+ unlock_session_list();
+ goto setup_error;
+ }
+
+ /* Filled the session array */
+ list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload));
+
+ unlock_session_list();
+
+ ret = LTTCOMM_OK;
+ break;
+ }
+ default:
+ /* Undefined command */
+ ret = setup_lttng_msg(cmd_ctx, 0);
+ if (ret < 0) {
+ goto setup_error;
+ }
+
+ ret = LTTCOMM_UND;
+ break;
+ }
+
+ /* Set return code */
+ cmd_ctx->llm->ret_code = ret;
+
+ if (cmd_ctx->session) {
+ unlock_session(cmd_ctx->session);
+ }
+
+ return ret;
+
+error:
+ if (cmd_ctx->llm == NULL) {
+ DBG("Missing llm structure. Allocating one.");
+ if (setup_lttng_msg(cmd_ctx, 0) < 0) {
+ goto setup_error;
+ }
+ }
+ /* Notify client of 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.