From: Jérémie Galarneau Date: Fri, 30 Nov 2018 19:29:32 +0000 (-0500) Subject: Launch the client management thread using lttng_thread X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=commitdiff_plain;h=917a718d4ec336ca98820f3cf56a2db57fc9b1dd Launch the client management thread using lttng_thread Signed-off-by: Jérémie Galarneau --- diff --git a/src/bin/lttng-sessiond/Makefile.am b/src/bin/lttng-sessiond/Makefile.am index 43962e7df..fa10b79fa 100644 --- a/src/bin/lttng-sessiond/Makefile.am +++ b/src/bin/lttng-sessiond/Makefile.am @@ -45,7 +45,8 @@ lttng_sessiond_SOURCES = utils.c utils.h \ thread-utils.c \ process-utils.c \ thread.c thread.h \ - health.c + health.c \ + client.c client.h if HAVE_LIBLTTNG_UST_CTL lttng_sessiond_SOURCES += trace-ust.c ust-registry.c ust-app.c \ diff --git a/src/bin/lttng-sessiond/client.c b/src/bin/lttng-sessiond/client.c new file mode 100644 index 000000000..119062c15 --- /dev/null +++ b/src/bin/lttng-sessiond/client.c @@ -0,0 +1,2556 @@ +/* + * Copyright (C) 2011 - David Goulet + * Mathieu Desnoyers + * 2013 - Jérémie Galarneau + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2 only, + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "client.h" +#include "lttng-sessiond.h" +#include "cmd.h" +#include "kernel.h" +#include "save.h" +#include "health-sessiond.h" +#include "testpoint.h" +#include "utils.h" + +static bool is_root; + +static struct thread_state { + pthread_cond_t cond; + pthread_mutex_t lock; + bool is_running; +} thread_state = { + .cond = PTHREAD_COND_INITIALIZER, + .lock = PTHREAD_MUTEX_INITIALIZER, + .is_running = false +}; + +void set_thread_state_running(void) +{ + pthread_mutex_lock(&thread_state.lock); + thread_state.is_running = true; + pthread_cond_broadcast(&thread_state.cond); + pthread_mutex_unlock(&thread_state.lock); +} + +static void wait_thread_state_running(void) +{ + pthread_mutex_lock(&thread_state.lock); + while (!thread_state.is_running) { + pthread_cond_wait(&thread_state.cond, + &thread_state.lock); + } + pthread_mutex_unlock(&thread_state.lock); +} + +/* + * 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 0 on success, negative value on error. + */ +static int setup_lttng_msg(struct command_ctx *cmd_ctx, + const void *payload_buf, size_t payload_len, + const void *cmd_header_buf, size_t cmd_header_len) +{ + int ret = 0; + const size_t header_len = sizeof(struct lttcomm_lttng_msg); + const size_t cmd_header_offset = header_len; + const size_t payload_offset = cmd_header_offset + cmd_header_len; + const size_t total_msg_size = header_len + cmd_header_len + payload_len; + + cmd_ctx->llm = zmalloc(total_msg_size); + + if (cmd_ctx->llm == NULL) { + PERROR("zmalloc"); + ret = -ENOMEM; + goto end; + } + + /* Copy common data */ + cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type; + cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid; + cmd_ctx->llm->cmd_header_size = cmd_header_len; + cmd_ctx->llm->data_size = payload_len; + cmd_ctx->lttng_msg_size = total_msg_size; + + /* Copy command header */ + if (cmd_header_len) { + memcpy(((uint8_t *) cmd_ctx->llm) + cmd_header_offset, cmd_header_buf, + cmd_header_len); + } + + /* Copy payload */ + if (payload_len) { + memcpy(((uint8_t *) cmd_ctx->llm) + payload_offset, payload_buf, + payload_len); + } + +end: + return ret; +} + +/* + * Start the thread_manage_consumer. This must be done after a lttng-consumerd + * exec or it will fails. + */ +static int spawn_consumer_thread(struct consumer_data *consumer_data) +{ + int ret, clock_ret; + struct timespec timeout; + + /* + * Make sure we set the readiness flag to 0 because we are NOT ready. + * This access to consumer_thread_is_ready does not need to be + * protected by consumer_data.cond_mutex (yet) since the consumer + * management thread has not been started at this point. + */ + consumer_data->consumer_thread_is_ready = 0; + + /* Setup pthread condition */ + ret = pthread_condattr_init(&consumer_data->condattr); + if (ret) { + errno = ret; + PERROR("pthread_condattr_init consumer data"); + goto error; + } + + /* + * Set the monotonic clock in order to make sure we DO NOT jump in time + * between the clock_gettime() call and the timedwait call. See bug #324 + * for a more details and how we noticed it. + */ + ret = pthread_condattr_setclock(&consumer_data->condattr, CLOCK_MONOTONIC); + if (ret) { + errno = ret; + PERROR("pthread_condattr_setclock consumer data"); + goto error; + } + + ret = pthread_cond_init(&consumer_data->cond, &consumer_data->condattr); + if (ret) { + errno = ret; + PERROR("pthread_cond_init consumer data"); + goto error; + } + + ret = pthread_create(&consumer_data->thread, default_pthread_attr(), + thread_manage_consumer, consumer_data); + if (ret) { + errno = ret; + PERROR("pthread_create consumer"); + ret = -1; + goto error; + } + + /* We are about to wait on a pthread condition */ + pthread_mutex_lock(&consumer_data->cond_mutex); + + /* Get time for sem_timedwait absolute timeout */ + clock_ret = lttng_clock_gettime(CLOCK_MONOTONIC, &timeout); + /* + * Set the timeout for the condition timed wait even if the clock gettime + * call fails since we might loop on that call and we want to avoid to + * increment the timeout too many times. + */ + timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT; + + /* + * The following loop COULD be skipped in some conditions so this is why we + * set ret to 0 in order to make sure at least one round of the loop is + * done. + */ + ret = 0; + + /* + * Loop until the condition is reached or when a timeout is reached. Note + * that the pthread_cond_timedwait(P) man page specifies that EINTR can NOT + * be returned but the pthread_cond(3), from the glibc-doc, says that it is + * possible. This loop does not take any chances and works with both of + * them. + */ + while (!consumer_data->consumer_thread_is_ready && ret != ETIMEDOUT) { + if (clock_ret < 0) { + PERROR("clock_gettime spawn consumer"); + /* Infinite wait for the consumerd thread to be ready */ + ret = pthread_cond_wait(&consumer_data->cond, + &consumer_data->cond_mutex); + } else { + ret = pthread_cond_timedwait(&consumer_data->cond, + &consumer_data->cond_mutex, &timeout); + } + } + + /* Release the pthread condition */ + pthread_mutex_unlock(&consumer_data->cond_mutex); + + if (ret != 0) { + errno = ret; + if (ret == ETIMEDOUT) { + int pth_ret; + + /* + * Call has timed out so we kill the kconsumerd_thread and return + * an error. + */ + ERR("Condition timed out. The consumer thread was never ready." + " Killing it"); + pth_ret = pthread_cancel(consumer_data->thread); + if (pth_ret < 0) { + PERROR("pthread_cancel consumer thread"); + } + } else { + PERROR("pthread_cond_wait failed consumer thread"); + } + /* Caller is expecting a negative value on failure. */ + ret = -1; + goto error; + } + + pthread_mutex_lock(&consumer_data->pid_mutex); + if (consumer_data->pid == 0) { + ERR("Consumerd did not start"); + pthread_mutex_unlock(&consumer_data->pid_mutex); + goto error; + } + pthread_mutex_unlock(&consumer_data->pid_mutex); + + return 0; + +error: + return ret; +} + +/* + * Fork and exec a consumer daemon (consumerd). + * + * Return pid if successful else -1. + */ +static pid_t spawn_consumerd(struct consumer_data *consumer_data) +{ + int ret; + pid_t pid; + const char *consumer_to_use; + const char *verbosity; + struct stat st; + + DBG("Spawning consumerd"); + + pid = fork(); + if (pid == 0) { + /* + * Exec consumerd. + */ + if (config.verbose_consumer) { + verbosity = "--verbose"; + } else if (lttng_opt_quiet) { + verbosity = "--quiet"; + } else { + verbosity = ""; + } + + switch (consumer_data->type) { + case LTTNG_CONSUMER_KERNEL: + /* + * Find out which consumerd to execute. We will first try the + * 64-bit path, then the sessiond's installation directory, and + * fallback on the 32-bit one, + */ + DBG3("Looking for a kernel consumer at these locations:"); + DBG3(" 1) %s", config.consumerd64_bin_path.value ? : "NULL"); + DBG3(" 2) %s/%s", INSTALL_BIN_PATH, DEFAULT_CONSUMERD_FILE); + DBG3(" 3) %s", config.consumerd32_bin_path.value ? : "NULL"); + if (stat(config.consumerd64_bin_path.value, &st) == 0) { + DBG3("Found location #1"); + consumer_to_use = config.consumerd64_bin_path.value; + } else if (stat(INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE, &st) == 0) { + DBG3("Found location #2"); + consumer_to_use = INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE; + } else if (config.consumerd32_bin_path.value && + stat(config.consumerd32_bin_path.value, &st) == 0) { + DBG3("Found location #3"); + consumer_to_use = config.consumerd32_bin_path.value; + } else { + DBG("Could not find any valid consumerd executable"); + ret = -EINVAL; + goto error; + } + DBG("Using kernel consumer at: %s", consumer_to_use); + (void) execl(consumer_to_use, + "lttng-consumerd", verbosity, "-k", + "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path, + "--consumerd-err-sock", consumer_data->err_unix_sock_path, + "--group", config.tracing_group_name.value, + NULL); + break; + case LTTNG_CONSUMER64_UST: + { + if (config.consumerd64_lib_dir.value) { + char *tmp; + size_t tmplen; + char *tmpnew; + + tmp = lttng_secure_getenv("LD_LIBRARY_PATH"); + if (!tmp) { + tmp = ""; + } + tmplen = strlen(config.consumerd64_lib_dir.value) + 1 /* : */ + strlen(tmp); + tmpnew = zmalloc(tmplen + 1 /* \0 */); + if (!tmpnew) { + ret = -ENOMEM; + goto error; + } + strcat(tmpnew, config.consumerd64_lib_dir.value); + if (tmp[0] != '\0') { + strcat(tmpnew, ":"); + strcat(tmpnew, tmp); + } + ret = setenv("LD_LIBRARY_PATH", tmpnew, 1); + free(tmpnew); + if (ret) { + ret = -errno; + goto error; + } + } + DBG("Using 64-bit UST consumer at: %s", config.consumerd64_bin_path.value); + (void) execl(config.consumerd64_bin_path.value, "lttng-consumerd", verbosity, "-u", + "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path, + "--consumerd-err-sock", consumer_data->err_unix_sock_path, + "--group", config.tracing_group_name.value, + NULL); + break; + } + case LTTNG_CONSUMER32_UST: + { + if (config.consumerd32_lib_dir.value) { + char *tmp; + size_t tmplen; + char *tmpnew; + + tmp = lttng_secure_getenv("LD_LIBRARY_PATH"); + if (!tmp) { + tmp = ""; + } + tmplen = strlen(config.consumerd32_lib_dir.value) + 1 /* : */ + strlen(tmp); + tmpnew = zmalloc(tmplen + 1 /* \0 */); + if (!tmpnew) { + ret = -ENOMEM; + goto error; + } + strcat(tmpnew, config.consumerd32_lib_dir.value); + if (tmp[0] != '\0') { + strcat(tmpnew, ":"); + strcat(tmpnew, tmp); + } + ret = setenv("LD_LIBRARY_PATH", tmpnew, 1); + free(tmpnew); + if (ret) { + ret = -errno; + goto error; + } + } + DBG("Using 32-bit UST consumer at: %s", config.consumerd32_bin_path.value); + (void) execl(config.consumerd32_bin_path.value, "lttng-consumerd", verbosity, "-u", + "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path, + "--consumerd-err-sock", consumer_data->err_unix_sock_path, + "--group", config.tracing_group_name.value, + NULL); + break; + } + default: + ERR("unknown consumer type"); + errno = 0; + } + if (errno != 0) { + PERROR("Consumer execl()"); + } + /* Reaching this point, we got a failure on our execl(). */ + exit(EXIT_FAILURE); + } else if (pid > 0) { + ret = pid; + } else { + PERROR("start consumer fork"); + ret = -errno; + } +error: + return ret; +} + +/* + * Spawn the consumerd daemon and session daemon thread. + */ +static int start_consumerd(struct consumer_data *consumer_data) +{ + int ret; + + /* + * Set the listen() state on the socket since there is a possible race + * between the exec() of the consumer daemon and this call if place in the + * consumer thread. See bug #366 for more details. + */ + ret = lttcomm_listen_unix_sock(consumer_data->err_sock); + if (ret < 0) { + goto error; + } + + pthread_mutex_lock(&consumer_data->pid_mutex); + if (consumer_data->pid != 0) { + pthread_mutex_unlock(&consumer_data->pid_mutex); + goto end; + } + + ret = spawn_consumerd(consumer_data); + if (ret < 0) { + ERR("Spawning consumerd failed"); + pthread_mutex_unlock(&consumer_data->pid_mutex); + goto error; + } + + /* Setting up the consumer_data pid */ + consumer_data->pid = ret; + DBG2("Consumer pid %d", consumer_data->pid); + pthread_mutex_unlock(&consumer_data->pid_mutex); + + DBG2("Spawning consumer control thread"); + ret = spawn_consumer_thread(consumer_data); + if (ret < 0) { + ERR("Fatal error spawning consumer control thread"); + goto error; + } + +end: + return 0; + +error: + /* Cleanup already created sockets on error. */ + if (consumer_data->err_sock >= 0) { + int err; + + err = close(consumer_data->err_sock); + if (err < 0) { + PERROR("close consumer data error socket"); + } + } + return ret; +} + +/* + * Copy consumer output from the tracing session to the domain session. The + * function also applies the right modification on a per domain basis for the + * trace files destination directory. + * + * Should *NOT* be called with RCU read-side lock held. + */ +static int copy_session_consumer(int domain, struct ltt_session *session) +{ + int ret; + const char *dir_name; + struct consumer_output *consumer; + + assert(session); + assert(session->consumer); + + switch (domain) { + case LTTNG_DOMAIN_KERNEL: + DBG3("Copying tracing session consumer output in kernel session"); + /* + * XXX: We should audit the session creation and what this function + * does "extra" in order to avoid a destroy since this function is used + * in the domain session creation (kernel and ust) only. Same for UST + * domain. + */ + if (session->kernel_session->consumer) { + consumer_output_put(session->kernel_session->consumer); + } + session->kernel_session->consumer = + consumer_copy_output(session->consumer); + /* Ease our life a bit for the next part */ + consumer = session->kernel_session->consumer; + dir_name = DEFAULT_KERNEL_TRACE_DIR; + break; + case LTTNG_DOMAIN_JUL: + case LTTNG_DOMAIN_LOG4J: + case LTTNG_DOMAIN_PYTHON: + case LTTNG_DOMAIN_UST: + DBG3("Copying tracing session consumer output in UST session"); + if (session->ust_session->consumer) { + consumer_output_put(session->ust_session->consumer); + } + session->ust_session->consumer = + consumer_copy_output(session->consumer); + /* Ease our life a bit for the next part */ + consumer = session->ust_session->consumer; + dir_name = DEFAULT_UST_TRACE_DIR; + break; + default: + ret = LTTNG_ERR_UNKNOWN_DOMAIN; + goto error; + } + + /* Append correct directory to subdir */ + strncat(consumer->subdir, dir_name, + sizeof(consumer->subdir) - strlen(consumer->subdir) - 1); + DBG3("Copy session consumer subdir %s", consumer->subdir); + + ret = LTTNG_OK; + +error: + return ret; +} + +/* + * Create an UST session and add it to the session ust list. + * + * Should *NOT* be called with RCU read-side lock held. + */ +static int create_ust_session(struct ltt_session *session, + struct lttng_domain *domain) +{ + int ret; + struct ltt_ust_session *lus = NULL; + + assert(session); + assert(domain); + assert(session->consumer); + + switch (domain->type) { + case LTTNG_DOMAIN_JUL: + case LTTNG_DOMAIN_LOG4J: + case LTTNG_DOMAIN_PYTHON: + case LTTNG_DOMAIN_UST: + break; + default: + ERR("Unknown UST domain on create session %d", domain->type); + ret = LTTNG_ERR_UNKNOWN_DOMAIN; + goto error; + } + + DBG("Creating UST session"); + + lus = trace_ust_create_session(session->id); + if (lus == NULL) { + ret = LTTNG_ERR_UST_SESS_FAIL; + goto error; + } + + lus->uid = session->uid; + lus->gid = session->gid; + lus->output_traces = session->output_traces; + lus->snapshot_mode = session->snapshot_mode; + lus->live_timer_interval = session->live_timer; + session->ust_session = lus; + if (session->shm_path[0]) { + strncpy(lus->root_shm_path, session->shm_path, + sizeof(lus->root_shm_path)); + lus->root_shm_path[sizeof(lus->root_shm_path) - 1] = '\0'; + strncpy(lus->shm_path, session->shm_path, + sizeof(lus->shm_path)); + lus->shm_path[sizeof(lus->shm_path) - 1] = '\0'; + strncat(lus->shm_path, "/ust", + sizeof(lus->shm_path) - strlen(lus->shm_path) - 1); + } + /* Copy session output to the newly created UST session */ + ret = copy_session_consumer(domain->type, session); + if (ret != LTTNG_OK) { + goto error; + } + + return LTTNG_OK; + +error: + free(lus); + session->ust_session = NULL; + return ret; +} + +/* + * 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 = LTTNG_ERR_KERN_SESS_FAIL; + goto error; + } + + /* Code flow safety */ + assert(session->kernel_session); + + /* Copy session output to the newly created Kernel session */ + ret = copy_session_consumer(LTTNG_DOMAIN_KERNEL, session); + if (ret != LTTNG_OK) { + goto error; + } + + session->kernel_session->uid = session->uid; + session->kernel_session->gid = session->gid; + session->kernel_session->output_traces = session->output_traces; + session->kernel_session->snapshot_mode = session->snapshot_mode; + + return LTTNG_OK; + +error: + trace_kernel_destroy_session(session->kernel_session); + session->kernel_session = NULL; + return ret; +} + +/* + * Count number of session permitted by uid/gid. + */ +static unsigned int lttng_sessions_count(uid_t uid, gid_t gid) +{ + unsigned int i = 0; + struct ltt_session *session; + const struct ltt_session_list *session_list = session_get_list(); + + DBG("Counting number of available session for UID %d GID %d", + uid, gid); + cds_list_for_each_entry(session, &session_list->head, list) { + if (!session_get(session)) { + continue; + } + session_lock(session); + /* Only count the sessions the user can control. */ + if (session_access_ok(session, uid, gid) && + !session->destroyed) { + i++; + } + session_unlock(session); + session_put(session); + } + return i; +} + +static int receive_userspace_probe(struct command_ctx *cmd_ctx, int sock, + int *sock_error, struct lttng_event *event) +{ + int fd, ret; + struct lttng_userspace_probe_location *probe_location; + const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; + struct lttng_dynamic_buffer probe_location_buffer; + struct lttng_buffer_view buffer_view; + + /* + * Create a buffer to store the serialized version of the probe + * location. + */ + lttng_dynamic_buffer_init(&probe_location_buffer); + ret = lttng_dynamic_buffer_set_size(&probe_location_buffer, + cmd_ctx->lsm->u.enable.userspace_probe_location_len); + if (ret) { + ret = LTTNG_ERR_NOMEM; + goto error; + } + + /* + * Receive the probe location. + */ + ret = lttcomm_recv_unix_sock(sock, probe_location_buffer.data, + probe_location_buffer.size); + if (ret <= 0) { + DBG("Nothing recv() from client var len data... continuing"); + *sock_error = 1; + lttng_dynamic_buffer_reset(&probe_location_buffer); + ret = LTTNG_ERR_PROBE_LOCATION_INVAL; + goto error; + } + + buffer_view = lttng_buffer_view_from_dynamic_buffer( + &probe_location_buffer, 0, probe_location_buffer.size); + + /* + * Extract the probe location from the serialized version. + */ + ret = lttng_userspace_probe_location_create_from_buffer( + &buffer_view, &probe_location); + if (ret < 0) { + WARN("Failed to create a userspace probe location from the received buffer"); + lttng_dynamic_buffer_reset( &probe_location_buffer); + ret = LTTNG_ERR_PROBE_LOCATION_INVAL; + goto error; + } + + /* + * Receive the file descriptor to the target binary from the client. + */ + DBG("Receiving userspace probe target FD from client ..."); + ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1); + if (ret <= 0) { + DBG("Nothing recv() from client userspace probe fd... continuing"); + *sock_error = 1; + ret = LTTNG_ERR_PROBE_LOCATION_INVAL; + goto error; + } + + /* + * Set the file descriptor received from the client through the unix + * socket in the probe location. + */ + lookup = lttng_userspace_probe_location_get_lookup_method(probe_location); + if (!lookup) { + ret = LTTNG_ERR_PROBE_LOCATION_INVAL; + goto error; + } + + /* + * From the kernel tracer's perspective, all userspace probe event types + * are all the same: a file and an offset. + */ + switch (lttng_userspace_probe_location_lookup_method_get_type(lookup)) { + case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF: + ret = lttng_userspace_probe_location_function_set_binary_fd( + probe_location, fd); + break; + case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT: + ret = lttng_userspace_probe_location_tracepoint_set_binary_fd( + probe_location, fd); + break; + default: + ret = LTTNG_ERR_PROBE_LOCATION_INVAL; + goto error; + } + + if (ret) { + ret = LTTNG_ERR_PROBE_LOCATION_INVAL; + goto error; + } + + /* Attach the probe location to the event. */ + ret = lttng_event_set_userspace_probe_location(event, probe_location); + if (ret) { + ret = LTTNG_ERR_PROBE_LOCATION_INVAL; + goto error; + } + + lttng_dynamic_buffer_reset(&probe_location_buffer); +error: + return ret; +} + +/* + * Join consumer thread + */ +static int join_consumer_thread(struct consumer_data *consumer_data) +{ + void *status; + + /* Consumer pid must be a real one. */ + if (consumer_data->pid > 0) { + int ret; + ret = kill(consumer_data->pid, SIGTERM); + if (ret) { + PERROR("Error killing consumer daemon"); + return ret; + } + return pthread_join(consumer_data->thread, &status); + } else { + return 0; + } +} + +/* + * Version of setup_lttng_msg() without command header. + */ +static int setup_lttng_msg_no_cmd_header(struct command_ctx *cmd_ctx, + void *payload_buf, size_t payload_len) +{ + return setup_lttng_msg(cmd_ctx, payload_buf, payload_len, NULL, 0); +} + +/* + * 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; + } +} + +/* + * Check if the current kernel tracer supports the session rotation feature. + * Return 1 if it does, 0 otherwise. + */ +static int check_rotate_compatible(void) +{ + int ret = 1; + + if (kernel_tracer_version.major != 2 || kernel_tracer_version.minor < 11) { + DBG("Kernel tracer version is not compatible with the rotation feature"); + ret = 0; + } + + return ret; +} + +/* + * Send data on a unix socket using the liblttsessiondcomm API. + * + * Return lttcomm error code. + */ +static int send_unix_sock(int sock, void *buf, size_t len) +{ + /* Check valid length */ + if (len == 0) { + return -1; + } + + return lttcomm_send_unix_sock(sock, buf, len); +} + +/* + * 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. + * + * "sock" is only used for special-case var. len data. + * + * Should *NOT* be called with RCU read-side lock held. + */ +static int process_client_msg(struct command_ctx *cmd_ctx, int sock, + int *sock_error) +{ + int ret = LTTNG_OK; + int need_tracing_session = 1; + int need_domain; + + DBG("Processing client command %d", cmd_ctx->lsm->cmd_type); + + assert(!rcu_read_ongoing()); + + *sock_error = 0; + + switch (cmd_ctx->lsm->cmd_type) { + case LTTNG_CREATE_SESSION: + case LTTNG_CREATE_SESSION_SNAPSHOT: + case LTTNG_CREATE_SESSION_LIVE: + case LTTNG_DESTROY_SESSION: + case LTTNG_LIST_SESSIONS: + case LTTNG_LIST_DOMAINS: + case LTTNG_START_TRACE: + case LTTNG_STOP_TRACE: + case LTTNG_DATA_PENDING: + case LTTNG_SNAPSHOT_ADD_OUTPUT: + case LTTNG_SNAPSHOT_DEL_OUTPUT: + case LTTNG_SNAPSHOT_LIST_OUTPUT: + case LTTNG_SNAPSHOT_RECORD: + case LTTNG_SAVE_SESSION: + case LTTNG_SET_SESSION_SHM_PATH: + case LTTNG_REGENERATE_METADATA: + case LTTNG_REGENERATE_STATEDUMP: + case LTTNG_REGISTER_TRIGGER: + case LTTNG_UNREGISTER_TRIGGER: + case LTTNG_ROTATE_SESSION: + case LTTNG_ROTATION_GET_INFO: + case LTTNG_ROTATION_SET_SCHEDULE: + case LTTNG_SESSION_LIST_ROTATION_SCHEDULES: + need_domain = 0; + break; + default: + need_domain = 1; + } + + if (config.no_kernel && need_domain + && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) { + if (!is_root) { + ret = LTTNG_ERR_NEED_ROOT_SESSIOND; + } else { + ret = LTTNG_ERR_KERN_NA; + } + goto error; + } + + /* Deny register consumer if we already have a spawned consumer. */ + if (cmd_ctx->lsm->cmd_type == LTTNG_REGISTER_CONSUMER) { + pthread_mutex_lock(&kconsumer_data.pid_mutex); + if (kconsumer_data.pid > 0) { + ret = LTTNG_ERR_KERN_CONSUMER_FAIL; + pthread_mutex_unlock(&kconsumer_data.pid_mutex); + goto error; + } + pthread_mutex_unlock(&kconsumer_data.pid_mutex); + } + + /* + * Check for command that don't needs to allocate a returned payload. We do + * this here so we don't have to make the call for no payload at each + * command. + */ + switch(cmd_ctx->lsm->cmd_type) { + case LTTNG_LIST_SESSIONS: + case LTTNG_LIST_TRACEPOINTS: + case LTTNG_LIST_TRACEPOINT_FIELDS: + case LTTNG_LIST_DOMAINS: + case LTTNG_LIST_CHANNELS: + case LTTNG_LIST_EVENTS: + case LTTNG_LIST_SYSCALLS: + case LTTNG_LIST_TRACKER_PIDS: + case LTTNG_DATA_PENDING: + case LTTNG_ROTATE_SESSION: + case LTTNG_ROTATION_GET_INFO: + case LTTNG_SESSION_LIST_ROTATION_SCHEDULES: + break; + default: + /* Setup lttng message with no payload */ + ret = setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0); + if (ret < 0) { + /* This label does not try to unlock the session */ + goto init_setup_error; + } + } + + /* Commands that DO NOT need a session. */ + switch (cmd_ctx->lsm->cmd_type) { + case LTTNG_CREATE_SESSION: + case LTTNG_CREATE_SESSION_SNAPSHOT: + case LTTNG_CREATE_SESSION_LIVE: + case LTTNG_LIST_SESSIONS: + case LTTNG_LIST_TRACEPOINTS: + case LTTNG_LIST_SYSCALLS: + case LTTNG_LIST_TRACEPOINT_FIELDS: + case LTTNG_SAVE_SESSION: + case LTTNG_REGISTER_TRIGGER: + case LTTNG_UNREGISTER_TRIGGER: + need_tracing_session = 0; + break; + default: + DBG("Getting session %s by name", cmd_ctx->lsm->session.name); + /* + * We keep the session list lock across _all_ commands + * for now, because the per-session lock does not + * handle teardown properly. + */ + session_lock_list(); + cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name); + if (cmd_ctx->session == NULL) { + ret = LTTNG_ERR_SESS_NOT_FOUND; + goto error; + } else { + /* Acquire lock for the session */ + session_lock(cmd_ctx->session); + } + break; + } + + /* + * Commands that need a valid session but should NOT create one if none + * exists. Instead of creating one and destroying it when the command is + * handled, process that right before so we save some round trip in useless + * code path. + */ + switch (cmd_ctx->lsm->cmd_type) { + case LTTNG_DISABLE_CHANNEL: + case LTTNG_DISABLE_EVENT: + switch (cmd_ctx->lsm->domain.type) { + case LTTNG_DOMAIN_KERNEL: + if (!cmd_ctx->session->kernel_session) { + ret = LTTNG_ERR_NO_CHANNEL; + goto error; + } + break; + case LTTNG_DOMAIN_JUL: + case LTTNG_DOMAIN_LOG4J: + case LTTNG_DOMAIN_PYTHON: + case LTTNG_DOMAIN_UST: + if (!cmd_ctx->session->ust_session) { + ret = LTTNG_ERR_NO_CHANNEL; + goto error; + } + break; + default: + ret = LTTNG_ERR_UNKNOWN_DOMAIN; + goto error; + } + default: + break; + } + + if (!need_domain) { + goto skip_domain; + } + + /* + * Check domain type for specific "pre-action". + */ + switch (cmd_ctx->lsm->domain.type) { + case LTTNG_DOMAIN_KERNEL: + if (!is_root) { + ret = LTTNG_ERR_NEED_ROOT_SESSIOND; + goto error; + } + + /* Consumer is in an ERROR state. Report back to client */ + if (uatomic_read(&kernel_consumerd_state) == CONSUMER_ERROR) { + ret = LTTNG_ERR_NO_KERNCONSUMERD; + goto error; + } + + /* Need a session for kernel command */ + if (need_tracing_session) { + if (cmd_ctx->session->kernel_session == NULL) { + ret = create_kernel_session(cmd_ctx->session); + if (ret < 0) { + ret = LTTNG_ERR_KERN_SESS_FAIL; + goto error; + } + } + + /* Start the kernel consumer daemon */ + pthread_mutex_lock(&kconsumer_data.pid_mutex); + if (kconsumer_data.pid == 0 && + cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) { + pthread_mutex_unlock(&kconsumer_data.pid_mutex); + ret = start_consumerd(&kconsumer_data); + if (ret < 0) { + ret = LTTNG_ERR_KERN_CONSUMER_FAIL; + goto error; + } + uatomic_set(&kernel_consumerd_state, CONSUMER_STARTED); + } else { + pthread_mutex_unlock(&kconsumer_data.pid_mutex); + } + + /* + * The consumer was just spawned so we need to add the socket to + * the consumer output of the session if exist. + */ + ret = consumer_create_socket(&kconsumer_data, + cmd_ctx->session->kernel_session->consumer); + if (ret < 0) { + goto error; + } + } + + break; + case LTTNG_DOMAIN_JUL: + case LTTNG_DOMAIN_LOG4J: + case LTTNG_DOMAIN_PYTHON: + case LTTNG_DOMAIN_UST: + { + if (!ust_app_supported()) { + ret = LTTNG_ERR_NO_UST; + goto error; + } + /* Consumer is in an ERROR state. Report back to client */ + if (uatomic_read(&ust_consumerd_state) == CONSUMER_ERROR) { + ret = LTTNG_ERR_NO_USTCONSUMERD; + goto error; + } + + if (need_tracing_session) { + /* Create UST session if none exist. */ + if (cmd_ctx->session->ust_session == NULL) { + ret = create_ust_session(cmd_ctx->session, + &cmd_ctx->lsm->domain); + if (ret != LTTNG_OK) { + goto error; + } + } + + /* Start the UST consumer daemons */ + /* 64-bit */ + pthread_mutex_lock(&ustconsumer64_data.pid_mutex); + if (config.consumerd64_bin_path.value && + ustconsumer64_data.pid == 0 && + cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) { + pthread_mutex_unlock(&ustconsumer64_data.pid_mutex); + ret = start_consumerd(&ustconsumer64_data); + if (ret < 0) { + ret = LTTNG_ERR_UST_CONSUMER64_FAIL; + uatomic_set(&ust_consumerd64_fd, -EINVAL); + goto error; + } + + uatomic_set(&ust_consumerd64_fd, ustconsumer64_data.cmd_sock); + uatomic_set(&ust_consumerd_state, CONSUMER_STARTED); + } else { + pthread_mutex_unlock(&ustconsumer64_data.pid_mutex); + } + + /* + * Setup socket for consumer 64 bit. No need for atomic access + * since it was set above and can ONLY be set in this thread. + */ + ret = consumer_create_socket(&ustconsumer64_data, + cmd_ctx->session->ust_session->consumer); + if (ret < 0) { + goto error; + } + + /* 32-bit */ + pthread_mutex_lock(&ustconsumer32_data.pid_mutex); + if (config.consumerd32_bin_path.value && + ustconsumer32_data.pid == 0 && + cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) { + pthread_mutex_unlock(&ustconsumer32_data.pid_mutex); + ret = start_consumerd(&ustconsumer32_data); + if (ret < 0) { + ret = LTTNG_ERR_UST_CONSUMER32_FAIL; + uatomic_set(&ust_consumerd32_fd, -EINVAL); + goto error; + } + + uatomic_set(&ust_consumerd32_fd, ustconsumer32_data.cmd_sock); + uatomic_set(&ust_consumerd_state, CONSUMER_STARTED); + } else { + pthread_mutex_unlock(&ustconsumer32_data.pid_mutex); + } + + /* + * Setup socket for consumer 32 bit. No need for atomic access + * since it was set above and can ONLY be set in this thread. + */ + ret = consumer_create_socket(&ustconsumer32_data, + cmd_ctx->session->ust_session->consumer); + if (ret < 0) { + goto error; + } + } + break; + } + default: + break; + } +skip_domain: + + /* Validate consumer daemon state when start/stop trace command */ + if (cmd_ctx->lsm->cmd_type == LTTNG_START_TRACE || + cmd_ctx->lsm->cmd_type == LTTNG_STOP_TRACE) { + switch (cmd_ctx->lsm->domain.type) { + case LTTNG_DOMAIN_NONE: + break; + case LTTNG_DOMAIN_JUL: + case LTTNG_DOMAIN_LOG4J: + case LTTNG_DOMAIN_PYTHON: + case LTTNG_DOMAIN_UST: + if (uatomic_read(&ust_consumerd_state) != CONSUMER_STARTED) { + ret = LTTNG_ERR_NO_USTCONSUMERD; + goto error; + } + break; + case LTTNG_DOMAIN_KERNEL: + if (uatomic_read(&kernel_consumerd_state) != CONSUMER_STARTED) { + ret = LTTNG_ERR_NO_KERNCONSUMERD; + goto error; + } + break; + default: + ret = LTTNG_ERR_UNKNOWN_DOMAIN; + goto error; + } + } + + /* + * Check that the UID or GID match that of the tracing session. + * The root user can interact with all sessions. + */ + if (need_tracing_session) { + if (!session_access_ok(cmd_ctx->session, + LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds), + LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds)) || + cmd_ctx->session->destroyed) { + ret = LTTNG_ERR_EPERM; + goto error; + } + } + + /* + * Send relayd information to consumer as soon as we have a domain and a + * session defined. + */ + if (cmd_ctx->session && need_domain) { + /* + * Setup relayd if not done yet. If the relayd information was already + * sent to the consumer, this call will gracefully return. + */ + ret = cmd_setup_relayd(cmd_ctx->session); + if (ret != LTTNG_OK) { + goto error; + } + } + + /* Process by command type */ + switch (cmd_ctx->lsm->cmd_type) { + case LTTNG_ADD_CONTEXT: + { + /* + * An LTTNG_ADD_CONTEXT command might have a supplementary + * payload if the context being added is an application context. + */ + if (cmd_ctx->lsm->u.context.ctx.ctx == + LTTNG_EVENT_CONTEXT_APP_CONTEXT) { + char *provider_name = NULL, *context_name = NULL; + size_t provider_name_len = + cmd_ctx->lsm->u.context.provider_name_len; + size_t context_name_len = + cmd_ctx->lsm->u.context.context_name_len; + + if (provider_name_len == 0 || context_name_len == 0) { + /* + * Application provider and context names MUST + * be provided. + */ + ret = -LTTNG_ERR_INVALID; + goto error; + } + + provider_name = zmalloc(provider_name_len + 1); + if (!provider_name) { + ret = -LTTNG_ERR_NOMEM; + goto error; + } + cmd_ctx->lsm->u.context.ctx.u.app_ctx.provider_name = + provider_name; + + context_name = zmalloc(context_name_len + 1); + if (!context_name) { + ret = -LTTNG_ERR_NOMEM; + goto error_add_context; + } + cmd_ctx->lsm->u.context.ctx.u.app_ctx.ctx_name = + context_name; + + ret = lttcomm_recv_unix_sock(sock, provider_name, + provider_name_len); + if (ret < 0) { + goto error_add_context; + } + + ret = lttcomm_recv_unix_sock(sock, context_name, + context_name_len); + if (ret < 0) { + goto error_add_context; + } + } + + /* + * cmd_add_context assumes ownership of the provider and context + * names. + */ + ret = cmd_add_context(cmd_ctx->session, + cmd_ctx->lsm->domain.type, + cmd_ctx->lsm->u.context.channel_name, + &cmd_ctx->lsm->u.context.ctx, + kernel_poll_pipe[1]); + + cmd_ctx->lsm->u.context.ctx.u.app_ctx.provider_name = NULL; + cmd_ctx->lsm->u.context.ctx.u.app_ctx.ctx_name = NULL; +error_add_context: + free(cmd_ctx->lsm->u.context.ctx.u.app_ctx.provider_name); + free(cmd_ctx->lsm->u.context.ctx.u.app_ctx.ctx_name); + if (ret < 0) { + goto error; + } + break; + } + case LTTNG_DISABLE_CHANNEL: + { + ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type, + cmd_ctx->lsm->u.disable.channel_name); + break; + } + case LTTNG_DISABLE_EVENT: + { + + /* + * FIXME: handle filter; for now we just receive the filter's + * bytecode along with the filter expression which are sent by + * liblttng-ctl and discard them. + * + * This fixes an issue where the client may block while sending + * the filter payload and encounter an error because the session + * daemon closes the socket without ever handling this data. + */ + size_t count = cmd_ctx->lsm->u.disable.expression_len + + cmd_ctx->lsm->u.disable.bytecode_len; + + if (count) { + char data[LTTNG_FILTER_MAX_LEN]; + + DBG("Discarding disable event command payload of size %zu", count); + while (count) { + ret = lttcomm_recv_unix_sock(sock, data, + count > sizeof(data) ? sizeof(data) : count); + if (ret < 0) { + goto error; + } + + count -= (size_t) ret; + } + } + /* FIXME: passing packed structure to non-packed pointer */ + ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type, + cmd_ctx->lsm->u.disable.channel_name, + &cmd_ctx->lsm->u.disable.event); + break; + } + case LTTNG_ENABLE_CHANNEL: + { + cmd_ctx->lsm->u.channel.chan.attr.extended.ptr = + (struct lttng_channel_extended *) &cmd_ctx->lsm->u.channel.extended; + ret = cmd_enable_channel(cmd_ctx->session, &cmd_ctx->lsm->domain, + &cmd_ctx->lsm->u.channel.chan, + kernel_poll_pipe[1]); + break; + } + case LTTNG_TRACK_PID: + { + ret = cmd_track_pid(cmd_ctx->session, + cmd_ctx->lsm->domain.type, + cmd_ctx->lsm->u.pid_tracker.pid); + break; + } + case LTTNG_UNTRACK_PID: + { + ret = cmd_untrack_pid(cmd_ctx->session, + cmd_ctx->lsm->domain.type, + cmd_ctx->lsm->u.pid_tracker.pid); + break; + } + case LTTNG_ENABLE_EVENT: + { + struct lttng_event *ev = NULL; + struct lttng_event_exclusion *exclusion = NULL; + struct lttng_filter_bytecode *bytecode = NULL; + char *filter_expression = NULL; + + /* Handle exclusion events and receive it from the client. */ + if (cmd_ctx->lsm->u.enable.exclusion_count > 0) { + size_t count = cmd_ctx->lsm->u.enable.exclusion_count; + + exclusion = zmalloc(sizeof(struct lttng_event_exclusion) + + (count * LTTNG_SYMBOL_NAME_LEN)); + if (!exclusion) { + ret = LTTNG_ERR_EXCLUSION_NOMEM; + goto error; + } + + DBG("Receiving var len exclusion event list from client ..."); + exclusion->count = count; + ret = lttcomm_recv_unix_sock(sock, exclusion->names, + count * LTTNG_SYMBOL_NAME_LEN); + if (ret <= 0) { + DBG("Nothing recv() from client var len data... continuing"); + *sock_error = 1; + free(exclusion); + ret = LTTNG_ERR_EXCLUSION_INVAL; + goto error; + } + } + + /* Get filter expression from client. */ + if (cmd_ctx->lsm->u.enable.expression_len > 0) { + size_t expression_len = + cmd_ctx->lsm->u.enable.expression_len; + + if (expression_len > LTTNG_FILTER_MAX_LEN) { + ret = LTTNG_ERR_FILTER_INVAL; + free(exclusion); + goto error; + } + + filter_expression = zmalloc(expression_len); + if (!filter_expression) { + free(exclusion); + ret = LTTNG_ERR_FILTER_NOMEM; + goto error; + } + + /* Receive var. len. data */ + DBG("Receiving var len filter's expression from client ..."); + ret = lttcomm_recv_unix_sock(sock, filter_expression, + expression_len); + if (ret <= 0) { + DBG("Nothing recv() from client var len data... continuing"); + *sock_error = 1; + free(filter_expression); + free(exclusion); + ret = LTTNG_ERR_FILTER_INVAL; + goto error; + } + } + + /* Handle filter and get bytecode from client. */ + if (cmd_ctx->lsm->u.enable.bytecode_len > 0) { + size_t bytecode_len = cmd_ctx->lsm->u.enable.bytecode_len; + + if (bytecode_len > LTTNG_FILTER_MAX_LEN) { + ret = LTTNG_ERR_FILTER_INVAL; + free(filter_expression); + free(exclusion); + goto error; + } + + bytecode = zmalloc(bytecode_len); + if (!bytecode) { + free(filter_expression); + free(exclusion); + ret = LTTNG_ERR_FILTER_NOMEM; + goto error; + } + + /* Receive var. len. data */ + DBG("Receiving var len filter's bytecode from client ..."); + ret = lttcomm_recv_unix_sock(sock, bytecode, bytecode_len); + if (ret <= 0) { + DBG("Nothing recv() from client var len data... continuing"); + *sock_error = 1; + free(filter_expression); + free(bytecode); + free(exclusion); + ret = LTTNG_ERR_FILTER_INVAL; + goto error; + } + + if ((bytecode->len + sizeof(*bytecode)) != bytecode_len) { + free(filter_expression); + free(bytecode); + free(exclusion); + ret = LTTNG_ERR_FILTER_INVAL; + goto error; + } + } + + ev = lttng_event_copy(&cmd_ctx->lsm->u.enable.event); + if (!ev) { + DBG("Failed to copy event: %s", + cmd_ctx->lsm->u.enable.event.name); + free(filter_expression); + free(bytecode); + free(exclusion); + ret = LTTNG_ERR_NOMEM; + goto error; + } + + + if (cmd_ctx->lsm->u.enable.userspace_probe_location_len > 0) { + /* Expect a userspace probe description. */ + ret = receive_userspace_probe(cmd_ctx, sock, sock_error, ev); + if (ret) { + free(filter_expression); + free(bytecode); + free(exclusion); + lttng_event_destroy(ev); + goto error; + } + } + + ret = cmd_enable_event(cmd_ctx->session, &cmd_ctx->lsm->domain, + cmd_ctx->lsm->u.enable.channel_name, + ev, + filter_expression, bytecode, exclusion, + kernel_poll_pipe[1]); + lttng_event_destroy(ev); + break; + } + case LTTNG_LIST_TRACEPOINTS: + { + struct lttng_event *events; + ssize_t nb_events; + + session_lock_list(); + nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events); + session_unlock_list(); + if (nb_events < 0) { + /* Return value is a negative lttng_error_code. */ + ret = -nb_events; + 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_no_cmd_header(cmd_ctx, events, + sizeof(struct lttng_event) * nb_events); + free(events); + + if (ret < 0) { + goto setup_error; + } + + ret = LTTNG_OK; + break; + } + case LTTNG_LIST_TRACEPOINT_FIELDS: + { + struct lttng_event_field *fields; + ssize_t nb_fields; + + session_lock_list(); + nb_fields = cmd_list_tracepoint_fields(cmd_ctx->lsm->domain.type, + &fields); + session_unlock_list(); + if (nb_fields < 0) { + /* Return value is a negative lttng_error_code. */ + ret = -nb_fields; + 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_no_cmd_header(cmd_ctx, fields, + sizeof(struct lttng_event_field) * nb_fields); + free(fields); + + if (ret < 0) { + goto setup_error; + } + + ret = LTTNG_OK; + break; + } + case LTTNG_LIST_SYSCALLS: + { + struct lttng_event *events; + ssize_t nb_events; + + nb_events = cmd_list_syscalls(&events); + if (nb_events < 0) { + /* Return value is a negative lttng_error_code. */ + ret = -nb_events; + 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_no_cmd_header(cmd_ctx, events, + sizeof(struct lttng_event) * nb_events); + free(events); + + if (ret < 0) { + goto setup_error; + } + + ret = LTTNG_OK; + break; + } + case LTTNG_LIST_TRACKER_PIDS: + { + int32_t *pids = NULL; + ssize_t nr_pids; + + nr_pids = cmd_list_tracker_pids(cmd_ctx->session, + cmd_ctx->lsm->domain.type, &pids); + if (nr_pids < 0) { + /* Return value is a negative lttng_error_code. */ + ret = -nr_pids; + 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_no_cmd_header(cmd_ctx, pids, + sizeof(int32_t) * nr_pids); + free(pids); + + if (ret < 0) { + goto setup_error; + } + + ret = LTTNG_OK; + break; + } + case LTTNG_SET_CONSUMER_URI: + { + size_t nb_uri, len; + struct lttng_uri *uris; + + nb_uri = cmd_ctx->lsm->u.uri.size; + len = nb_uri * sizeof(struct lttng_uri); + + if (nb_uri == 0) { + ret = LTTNG_ERR_INVALID; + goto error; + } + + uris = zmalloc(len); + if (uris == NULL) { + ret = LTTNG_ERR_FATAL; + goto error; + } + + /* Receive variable len data */ + DBG("Receiving %zu URI(s) from client ...", nb_uri); + ret = lttcomm_recv_unix_sock(sock, uris, len); + if (ret <= 0) { + DBG("No URIs received from client... continuing"); + *sock_error = 1; + ret = LTTNG_ERR_SESSION_FAIL; + free(uris); + goto error; + } + + ret = cmd_set_consumer_uri(cmd_ctx->session, nb_uri, uris); + free(uris); + if (ret != LTTNG_OK) { + goto error; + } + + + break; + } + case LTTNG_START_TRACE: + { + /* + * On the first start, if we have a kernel session and we have + * enabled time or size-based rotations, we have to make sure + * the kernel tracer supports it. + */ + if (!cmd_ctx->session->has_been_started && \ + cmd_ctx->session->kernel_session && \ + (cmd_ctx->session->rotate_timer_period || \ + cmd_ctx->session->rotate_size) && \ + !check_rotate_compatible()) { + DBG("Kernel tracer version is not compatible with the rotation feature"); + ret = LTTNG_ERR_ROTATION_WRONG_VERSION; + goto error; + } + ret = cmd_start_trace(cmd_ctx->session); + break; + } + case LTTNG_STOP_TRACE: + { + ret = cmd_stop_trace(cmd_ctx->session); + break; + } + case LTTNG_CREATE_SESSION: + { + size_t nb_uri, len; + struct lttng_uri *uris = NULL; + + nb_uri = cmd_ctx->lsm->u.uri.size; + len = nb_uri * sizeof(struct lttng_uri); + + if (nb_uri > 0) { + uris = zmalloc(len); + if (uris == NULL) { + ret = LTTNG_ERR_FATAL; + goto error; + } + + /* Receive variable len data */ + DBG("Waiting for %zu URIs from client ...", nb_uri); + ret = lttcomm_recv_unix_sock(sock, uris, len); + if (ret <= 0) { + DBG("No URIs received from client... continuing"); + *sock_error = 1; + ret = LTTNG_ERR_SESSION_FAIL; + free(uris); + goto error; + } + + if (nb_uri == 1 && uris[0].dtype != LTTNG_DST_PATH) { + DBG("Creating session with ONE network URI is a bad call"); + ret = LTTNG_ERR_SESSION_FAIL; + free(uris); + goto error; + } + } + + ret = cmd_create_session_uri(cmd_ctx->lsm->session.name, uris, nb_uri, + &cmd_ctx->creds, 0); + + free(uris); + + break; + } + case LTTNG_DESTROY_SESSION: + { + ret = cmd_destroy_session(cmd_ctx->session, + notification_thread_handle); + break; + } + case LTTNG_LIST_DOMAINS: + { + ssize_t nb_dom; + struct lttng_domain *domains = NULL; + + nb_dom = cmd_list_domains(cmd_ctx->session, &domains); + if (nb_dom < 0) { + /* Return value is a negative lttng_error_code. */ + ret = -nb_dom; + goto error; + } + + ret = setup_lttng_msg_no_cmd_header(cmd_ctx, domains, + nb_dom * sizeof(struct lttng_domain)); + free(domains); + + if (ret < 0) { + goto setup_error; + } + + ret = LTTNG_OK; + break; + } + case LTTNG_LIST_CHANNELS: + { + ssize_t payload_size; + struct lttng_channel *channels = NULL; + + payload_size = cmd_list_channels(cmd_ctx->lsm->domain.type, + cmd_ctx->session, &channels); + if (payload_size < 0) { + /* Return value is a negative lttng_error_code. */ + ret = -payload_size; + goto error; + } + + ret = setup_lttng_msg_no_cmd_header(cmd_ctx, channels, + payload_size); + free(channels); + + if (ret < 0) { + goto setup_error; + } + + ret = LTTNG_OK; + break; + } + case LTTNG_LIST_EVENTS: + { + ssize_t nb_event; + struct lttng_event *events = NULL; + struct lttcomm_event_command_header cmd_header; + size_t total_size; + + memset(&cmd_header, 0, sizeof(cmd_header)); + /* Extended infos are included at the end of events */ + nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, + cmd_ctx->session, cmd_ctx->lsm->u.list.channel_name, + &events, &total_size); + + if (nb_event < 0) { + /* Return value is a negative lttng_error_code. */ + ret = -nb_event; + goto error; + } + + cmd_header.nb_events = nb_event; + ret = setup_lttng_msg(cmd_ctx, events, total_size, + &cmd_header, sizeof(cmd_header)); + free(events); + + if (ret < 0) { + goto setup_error; + } + + ret = LTTNG_OK; + break; + } + case LTTNG_LIST_SESSIONS: + { + unsigned int nr_sessions; + void *sessions_payload; + size_t payload_len; + + session_lock_list(); + nr_sessions = lttng_sessions_count( + LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds), + LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds)); + payload_len = sizeof(struct lttng_session) * nr_sessions; + sessions_payload = zmalloc(payload_len); + + if (!sessions_payload) { + session_unlock_list(); + ret = -ENOMEM; + goto setup_error; + } + + cmd_list_lttng_sessions(sessions_payload, + LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds), + LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds)); + session_unlock_list(); + + ret = setup_lttng_msg_no_cmd_header(cmd_ctx, sessions_payload, + payload_len); + free(sessions_payload); + + if (ret < 0) { + goto setup_error; + } + + ret = LTTNG_OK; + break; + } + case LTTNG_REGISTER_CONSUMER: + { + struct consumer_data *cdata; + + switch (cmd_ctx->lsm->domain.type) { + case LTTNG_DOMAIN_KERNEL: + cdata = &kconsumer_data; + break; + default: + ret = LTTNG_ERR_UND; + goto error; + } + + ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type, + cmd_ctx->lsm->u.reg.path, cdata); + break; + } + case LTTNG_DATA_PENDING: + { + int pending_ret; + uint8_t pending_ret_byte; + + pending_ret = cmd_data_pending(cmd_ctx->session); + + /* + * FIXME + * + * This function may returns 0 or 1 to indicate whether or not + * there is data pending. In case of error, it should return an + * LTTNG_ERR code. However, some code paths may still return + * a nondescript error code, which we handle by returning an + * "unknown" error. + */ + if (pending_ret == 0 || pending_ret == 1) { + /* + * ret will be set to LTTNG_OK at the end of + * this function. + */ + } else if (pending_ret < 0) { + ret = LTTNG_ERR_UNK; + goto setup_error; + } else { + ret = pending_ret; + goto setup_error; + } + + pending_ret_byte = (uint8_t) pending_ret; + + /* 1 byte to return whether or not data is pending */ + ret = setup_lttng_msg_no_cmd_header(cmd_ctx, + &pending_ret_byte, 1); + + if (ret < 0) { + goto setup_error; + } + + ret = LTTNG_OK; + break; + } + case LTTNG_SNAPSHOT_ADD_OUTPUT: + { + struct lttcomm_lttng_output_id reply; + + ret = cmd_snapshot_add_output(cmd_ctx->session, + &cmd_ctx->lsm->u.snapshot_output.output, &reply.id); + if (ret != LTTNG_OK) { + goto error; + } + + ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &reply, + sizeof(reply)); + if (ret < 0) { + goto setup_error; + } + + /* Copy output list into message payload */ + ret = LTTNG_OK; + break; + } + case LTTNG_SNAPSHOT_DEL_OUTPUT: + { + ret = cmd_snapshot_del_output(cmd_ctx->session, + &cmd_ctx->lsm->u.snapshot_output.output); + break; + } + case LTTNG_SNAPSHOT_LIST_OUTPUT: + { + ssize_t nb_output; + struct lttng_snapshot_output *outputs = NULL; + + nb_output = cmd_snapshot_list_outputs(cmd_ctx->session, &outputs); + if (nb_output < 0) { + ret = -nb_output; + goto error; + } + + assert((nb_output > 0 && outputs) || nb_output == 0); + ret = setup_lttng_msg_no_cmd_header(cmd_ctx, outputs, + nb_output * sizeof(struct lttng_snapshot_output)); + free(outputs); + + if (ret < 0) { + goto setup_error; + } + + ret = LTTNG_OK; + break; + } + case LTTNG_SNAPSHOT_RECORD: + { + ret = cmd_snapshot_record(cmd_ctx->session, + &cmd_ctx->lsm->u.snapshot_record.output, + cmd_ctx->lsm->u.snapshot_record.wait); + break; + } + case LTTNG_CREATE_SESSION_SNAPSHOT: + { + size_t nb_uri, len; + struct lttng_uri *uris = NULL; + + nb_uri = cmd_ctx->lsm->u.uri.size; + len = nb_uri * sizeof(struct lttng_uri); + + if (nb_uri > 0) { + uris = zmalloc(len); + if (uris == NULL) { + ret = LTTNG_ERR_FATAL; + goto error; + } + + /* Receive variable len data */ + DBG("Waiting for %zu URIs from client ...", nb_uri); + ret = lttcomm_recv_unix_sock(sock, uris, len); + if (ret <= 0) { + DBG("No URIs received from client... continuing"); + *sock_error = 1; + ret = LTTNG_ERR_SESSION_FAIL; + free(uris); + goto error; + } + + if (nb_uri == 1 && uris[0].dtype != LTTNG_DST_PATH) { + DBG("Creating session with ONE network URI is a bad call"); + ret = LTTNG_ERR_SESSION_FAIL; + free(uris); + goto error; + } + } + + ret = cmd_create_session_snapshot(cmd_ctx->lsm->session.name, uris, + nb_uri, &cmd_ctx->creds); + free(uris); + break; + } + case LTTNG_CREATE_SESSION_LIVE: + { + size_t nb_uri, len; + struct lttng_uri *uris = NULL; + + nb_uri = cmd_ctx->lsm->u.uri.size; + len = nb_uri * sizeof(struct lttng_uri); + + if (nb_uri > 0) { + uris = zmalloc(len); + if (uris == NULL) { + ret = LTTNG_ERR_FATAL; + goto error; + } + + /* Receive variable len data */ + DBG("Waiting for %zu URIs from client ...", nb_uri); + ret = lttcomm_recv_unix_sock(sock, uris, len); + if (ret <= 0) { + DBG("No URIs received from client... continuing"); + *sock_error = 1; + ret = LTTNG_ERR_SESSION_FAIL; + free(uris); + goto error; + } + + if (nb_uri == 1 && uris[0].dtype != LTTNG_DST_PATH) { + DBG("Creating session with ONE network URI is a bad call"); + ret = LTTNG_ERR_SESSION_FAIL; + free(uris); + goto error; + } + } + + ret = cmd_create_session_uri(cmd_ctx->lsm->session.name, uris, + nb_uri, &cmd_ctx->creds, cmd_ctx->lsm->u.session_live.timer_interval); + free(uris); + break; + } + case LTTNG_SAVE_SESSION: + { + ret = cmd_save_sessions(&cmd_ctx->lsm->u.save_session.attr, + &cmd_ctx->creds); + break; + } + case LTTNG_SET_SESSION_SHM_PATH: + { + ret = cmd_set_session_shm_path(cmd_ctx->session, + cmd_ctx->lsm->u.set_shm_path.shm_path); + break; + } + case LTTNG_REGENERATE_METADATA: + { + ret = cmd_regenerate_metadata(cmd_ctx->session); + break; + } + case LTTNG_REGENERATE_STATEDUMP: + { + ret = cmd_regenerate_statedump(cmd_ctx->session); + break; + } + case LTTNG_REGISTER_TRIGGER: + { + ret = cmd_register_trigger(cmd_ctx, sock, + notification_thread_handle); + break; + } + case LTTNG_UNREGISTER_TRIGGER: + { + ret = cmd_unregister_trigger(cmd_ctx, sock, + notification_thread_handle); + break; + } + case LTTNG_ROTATE_SESSION: + { + struct lttng_rotate_session_return rotate_return; + + DBG("Client rotate session \"%s\"", cmd_ctx->session->name); + + memset(&rotate_return, 0, sizeof(rotate_return)); + if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) { + DBG("Kernel tracer version is not compatible with the rotation feature"); + ret = LTTNG_ERR_ROTATION_WRONG_VERSION; + goto error; + } + + ret = cmd_rotate_session(cmd_ctx->session, &rotate_return); + if (ret < 0) { + ret = -ret; + goto error; + } + + ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &rotate_return, + sizeof(rotate_return)); + if (ret < 0) { + ret = -ret; + goto error; + } + + ret = LTTNG_OK; + break; + } + case LTTNG_ROTATION_GET_INFO: + { + struct lttng_rotation_get_info_return get_info_return; + + memset(&get_info_return, 0, sizeof(get_info_return)); + ret = cmd_rotate_get_info(cmd_ctx->session, &get_info_return, + cmd_ctx->lsm->u.get_rotation_info.rotation_id); + if (ret < 0) { + ret = -ret; + goto error; + } + + ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &get_info_return, + sizeof(get_info_return)); + if (ret < 0) { + ret = -ret; + goto error; + } + + ret = LTTNG_OK; + break; + } + case LTTNG_ROTATION_SET_SCHEDULE: + { + bool set_schedule; + enum lttng_rotation_schedule_type schedule_type; + uint64_t value; + + if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) { + DBG("Kernel tracer version does not support session rotations"); + ret = LTTNG_ERR_ROTATION_WRONG_VERSION; + goto error; + } + + set_schedule = cmd_ctx->lsm->u.rotation_set_schedule.set == 1; + schedule_type = (enum lttng_rotation_schedule_type) cmd_ctx->lsm->u.rotation_set_schedule.type; + value = cmd_ctx->lsm->u.rotation_set_schedule.value; + + ret = cmd_rotation_set_schedule(cmd_ctx->session, + set_schedule, + schedule_type, + value, + notification_thread_handle); + if (ret != LTTNG_OK) { + goto error; + } + + break; + } + case LTTNG_SESSION_LIST_ROTATION_SCHEDULES: + { + struct lttng_session_list_schedules_return schedules = { + .periodic.set = !!cmd_ctx->session->rotate_timer_period, + .periodic.value = cmd_ctx->session->rotate_timer_period, + .size.set = !!cmd_ctx->session->rotate_size, + .size.value = cmd_ctx->session->rotate_size, + }; + + ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &schedules, + sizeof(schedules)); + if (ret < 0) { + ret = -ret; + goto error; + } + + ret = LTTNG_OK; + break; + } + default: + ret = LTTNG_ERR_UND; + break; + } + +error: + if (cmd_ctx->llm == NULL) { + DBG("Missing llm structure. Allocating one."); + if (setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0) < 0) { + goto setup_error; + } + } + /* Set return code */ + cmd_ctx->llm->ret_code = ret; +setup_error: + if (cmd_ctx->session) { + session_unlock(cmd_ctx->session); + session_put(cmd_ctx->session); + } + if (need_tracing_session) { + session_unlock_list(); + } +init_setup_error: + assert(!rcu_read_ongoing()); + return ret; +} + +static int create_client_sock(void) +{ + int ret, client_sock; + const mode_t old_umask = umask(0); + + /* Create client tool unix socket */ + client_sock = lttcomm_create_unix_sock(config.client_unix_sock_path.value); + if (client_sock < 0) { + ERR("Create unix sock failed: %s", config.client_unix_sock_path.value); + ret = -1; + goto end; + } + + /* Set the cloexec flag */ + ret = utils_set_fd_cloexec(client_sock); + if (ret < 0) { + ERR("Unable to set CLOEXEC flag to the client Unix socket (fd: %d). " + "Continuing but note that the consumer daemon will have a " + "reference to this socket on exec()", client_sock); + } + + /* File permission MUST be 660 */ + ret = chmod(config.client_unix_sock_path.value, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP); + if (ret < 0) { + ERR("Set file permissions failed: %s", config.client_unix_sock_path.value); + PERROR("chmod"); + goto end; + } + DBG("Created client socket (fd = %i)", client_sock); + ret = client_sock; +end: + umask(old_umask); + return ret; +} + +static void cleanup_client_thread(void *data) +{ + struct lttng_pipe *quit_pipe = data; + + lttng_pipe_destroy(quit_pipe); +} + +/* + * This thread manage all clients request using the unix client socket for + * communication. + */ +static void *thread_manage_clients(void *data) +{ + int sock = -1, ret, i, pollfd, err = -1; + int sock_error; + uint32_t revents, nb_fd; + struct command_ctx *cmd_ctx = NULL; + struct lttng_poll_event events; + int client_sock = -1; + struct lttng_pipe *quit_pipe = data; + const int thread_quit_pipe_fd = lttng_pipe_get_readfd(quit_pipe); + + DBG("[thread] Manage client started"); + + is_root = (getuid() == 0); + + client_sock = create_client_sock(); + if (client_sock < 0) { + goto error_listen; + } + + rcu_register_thread(); + + health_register(health_sessiond, HEALTH_SESSIOND_TYPE_CMD); + + health_code_update(); + + ret = lttcomm_listen_unix_sock(client_sock); + if (ret < 0) { + goto error_listen; + } + + /* + * Pass 2 as size here for the thread quit pipe and client_sock. Nothing + * more will be added to this poll set. + */ + ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC); + if (ret < 0) { + goto error_create_poll; + } + + /* Add the application registration socket */ + ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI); + if (ret < 0) { + goto error; + } + + /* Add thread quit pipe */ + ret = lttng_poll_add(&events, thread_quit_pipe_fd, LPOLLIN | LPOLLERR); + if (ret < 0) { + goto error; + } + + /* This testpoint is after we signal readiness to the parent. */ + if (testpoint(sessiond_thread_manage_clients)) { + goto error; + } + + if (testpoint(sessiond_thread_manage_clients_before_loop)) { + goto error; + } + + health_code_update(); + + /* Set state as running. */ + set_thread_state_running(); + + while (1) { + const struct cmd_completion_handler *cmd_completion_handler; + + DBG("Accepting client command ..."); + + /* Inifinite blocking call, waiting for transmission */ + restart: + health_poll_entry(); + ret = lttng_poll_wait(&events, -1); + health_poll_exit(); + if (ret < 0) { + /* + * Restart interrupted system call. + */ + if (errno == EINTR) { + goto restart; + } + goto error; + } + + nb_fd = ret; + + for (i = 0; i < nb_fd; i++) { + revents = LTTNG_POLL_GETEV(&events, i); + pollfd = LTTNG_POLL_GETFD(&events, i); + + health_code_update(); + + if (!revents) { + /* No activity for this FD (poll implementation). */ + continue; + } + + if (pollfd == thread_quit_pipe_fd) { + err = 0; + goto exit; + } else { + /* Event on the registration socket */ + if (revents & LPOLLIN) { + continue; + } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) { + ERR("Client socket poll error"); + goto error; + } else { + ERR("Unexpected poll events %u for sock %d", revents, pollfd); + goto error; + } + } + } + + DBG("Wait for client response"); + + health_code_update(); + + sock = lttcomm_accept_unix_sock(client_sock); + if (sock < 0) { + goto error; + } + + /* + * Set the CLOEXEC flag. Return code is useless because either way, the + * show must go on. + */ + (void) utils_set_fd_cloexec(sock); + + /* Set socket option for credentials retrieval */ + ret = lttcomm_setsockopt_creds_unix_sock(sock); + if (ret < 0) { + goto error; + } + + /* Allocate context command to process the client request */ + cmd_ctx = zmalloc(sizeof(struct command_ctx)); + if (cmd_ctx == NULL) { + PERROR("zmalloc cmd_ctx"); + goto error; + } + + /* Allocate data buffer for reception */ + cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg)); + if (cmd_ctx->lsm == NULL) { + PERROR("zmalloc cmd_ctx->lsm"); + goto error; + } + + cmd_ctx->llm = NULL; + cmd_ctx->session = NULL; + + health_code_update(); + + /* + * 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_creds_unix_sock(sock, cmd_ctx->lsm, + sizeof(struct lttcomm_session_msg), &cmd_ctx->creds); + if (ret <= 0) { + DBG("Nothing recv() from client... continuing"); + ret = close(sock); + if (ret) { + PERROR("close"); + } + sock = -1; + clean_command_ctx(&cmd_ctx); + continue; + } + + health_code_update(); + + // TODO: Validate cmd_ctx including sanity check for + // security purpose. + + rcu_thread_online(); + /* + * 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, sock, &sock_error); + rcu_thread_offline(); + if (ret < 0) { + ret = close(sock); + if (ret) { + PERROR("close"); + } + sock = -1; + /* + * TODO: Inform client somehow of the fatal error. At + * this point, ret < 0 means that a zmalloc failed + * (ENOMEM). Error detected but still accept + * command, unless a socket error has been + * detected. + */ + clean_command_ctx(&cmd_ctx); + continue; + } + + cmd_completion_handler = cmd_pop_completion_handler(); + if (cmd_completion_handler) { + enum lttng_error_code completion_code; + + completion_code = cmd_completion_handler->run( + cmd_completion_handler->data); + if (completion_code != LTTNG_OK) { + clean_command_ctx(&cmd_ctx); + continue; + } + } + + health_code_update(); + + DBG("Sending response (size: %d, retcode: %s (%d))", + cmd_ctx->lttng_msg_size, + lttng_strerror(-cmd_ctx->llm->ret_code), + 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"); + } + + /* End of transmission */ + ret = close(sock); + if (ret) { + PERROR("close"); + } + sock = -1; + + clean_command_ctx(&cmd_ctx); + + health_code_update(); + } + +exit: +error: + if (sock >= 0) { + ret = close(sock); + if (ret) { + PERROR("close"); + } + } + + lttng_poll_clean(&events); + clean_command_ctx(&cmd_ctx); + +error_listen: +error_create_poll: + unlink(config.client_unix_sock_path.value); + if (client_sock >= 0) { + ret = close(client_sock); + if (ret) { + PERROR("close"); + } + } + + if (err) { + health_error(); + ERR("Health error occurred in %s", __func__); + } + + health_unregister(health_sessiond); + + DBG("Client thread dying"); + + rcu_unregister_thread(); + + /* + * Since we are creating the consumer threads, we own them, so we need + * to join them before our thread exits. + */ + ret = join_consumer_thread(&kconsumer_data); + if (ret) { + errno = ret; + PERROR("join_consumer"); + } + + ret = join_consumer_thread(&ustconsumer32_data); + if (ret) { + errno = ret; + PERROR("join_consumer ust32"); + } + + ret = join_consumer_thread(&ustconsumer64_data); + if (ret) { + errno = ret; + PERROR("join_consumer ust64"); + } + return NULL; +} + +static +bool shutdown_client_thread(void *thread_data) +{ + struct lttng_pipe *client_quit_pipe = thread_data; + const int write_fd = lttng_pipe_get_writefd(client_quit_pipe); + + return notify_thread_pipe(write_fd) == 1; +} + +struct lttng_thread *launch_client_thread(void) +{ + struct lttng_pipe *client_quit_pipe; + struct lttng_thread *thread; + + client_quit_pipe = lttng_pipe_open(FD_CLOEXEC); + if (!client_quit_pipe) { + goto error; + } + + thread = lttng_thread_create("Client management", + thread_manage_clients, + shutdown_client_thread, + cleanup_client_thread, + client_quit_pipe); + if (!thread) { + goto error; + } + + /* + * This thread is part of the threads that need to be fully + * initialized before the session daemon is marked as "ready". + */ + wait_thread_state_running(); + + return thread; +error: + cleanup_client_thread(client_quit_pipe); + return NULL; +} diff --git a/src/bin/lttng-sessiond/client.h b/src/bin/lttng-sessiond/client.h new file mode 100644 index 000000000..f821398b8 --- /dev/null +++ b/src/bin/lttng-sessiond/client.h @@ -0,0 +1,27 @@ +/* + * Copyright (C) 2011 - David Goulet + * Mathieu Desnoyers + * 2013 - Jérémie Galarneau + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2 only, + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#ifndef CLIENT_SESSIOND_H +#define CLIENT_SESSIOND_H + +#include "thread.h" + +struct lttng_thread *launch_client_thread(void); + +#endif /* CLIENT_SESSIOND_H */ diff --git a/src/bin/lttng-sessiond/globals.c b/src/bin/lttng-sessiond/globals.c index 63fd79938..82a51512a 100644 --- a/src/bin/lttng-sessiond/globals.c +++ b/src/bin/lttng-sessiond/globals.c @@ -31,6 +31,8 @@ struct notification_thread_handle *notification_thread_handle; struct lttng_ht *agent_apps_ht_by_sock = NULL; int kernel_tracer_fd = -1; +struct lttng_kernel_tracer_version kernel_tracer_version; +struct lttng_kernel_tracer_abi_version kernel_tracer_abi_version; int apps_cmd_notify_pipe[2] = { -1, -1 }; int kernel_poll_pipe[2] = { -1, -1 }; @@ -39,3 +41,39 @@ pid_t ppid; pid_t child_ppid; struct sessiond_config config; + +struct consumer_data kconsumer_data = { + .type = LTTNG_CONSUMER_KERNEL, + .err_sock = -1, + .cmd_sock = -1, + .channel_monitor_pipe = -1, + .pid_mutex = PTHREAD_MUTEX_INITIALIZER, + .lock = PTHREAD_MUTEX_INITIALIZER, + .cond = PTHREAD_COND_INITIALIZER, + .cond_mutex = PTHREAD_MUTEX_INITIALIZER, +}; + +struct consumer_data ustconsumer64_data = { + .type = LTTNG_CONSUMER64_UST, + .err_sock = -1, + .cmd_sock = -1, + .channel_monitor_pipe = -1, + .pid_mutex = PTHREAD_MUTEX_INITIALIZER, + .lock = PTHREAD_MUTEX_INITIALIZER, + .cond = PTHREAD_COND_INITIALIZER, + .cond_mutex = PTHREAD_MUTEX_INITIALIZER, +}; + +struct consumer_data ustconsumer32_data = { + .type = LTTNG_CONSUMER32_UST, + .err_sock = -1, + .cmd_sock = -1, + .channel_monitor_pipe = -1, + .pid_mutex = PTHREAD_MUTEX_INITIALIZER, + .lock = PTHREAD_MUTEX_INITIALIZER, + .cond = PTHREAD_COND_INITIALIZER, + .cond_mutex = PTHREAD_MUTEX_INITIALIZER, +}; + +enum consumerd_state ust_consumerd_state; +enum consumerd_state kernel_consumerd_state; diff --git a/src/bin/lttng-sessiond/load-session-thread.c b/src/bin/lttng-sessiond/load-session-thread.c index a6c393c9f..a93a799f6 100644 --- a/src/bin/lttng-sessiond/load-session-thread.c +++ b/src/bin/lttng-sessiond/load-session-thread.c @@ -30,15 +30,6 @@ void load_session_destroy_data(struct load_session_thread_data *data) if (!data) { return; } - - if (data->sem_initialized) { - int ret; - - ret = sem_destroy(&data->message_thread_ready); - if (ret) { - PERROR("sem_destroy message_thread_ready"); - } - } } /* @@ -50,7 +41,6 @@ void load_session_destroy_data(struct load_session_thread_data *data) */ int load_session_init_data(struct load_session_thread_data **data) { - int ret; struct load_session_thread_data *_data = NULL; assert(data); @@ -64,12 +54,6 @@ int load_session_init_data(struct load_session_thread_data **data) PERROR("zmalloc load session info"); goto error; } - ret = sem_init(&_data->message_thread_ready, 0, 0); - if (ret) { - PERROR("sem_init message_thread_ready"); - goto error; - } - _data->sem_initialized = 1; *data = _data; return 0; @@ -90,19 +74,12 @@ void *thread_load_session(void *data) DBG("[load-session-thread] Load session"); - ret = sem_wait(&info->message_thread_ready); - if (ret) { - PERROR("sem_wait message_thread_ready"); - goto end; - } - /* Override existing session and autoload also. */ ret = config_load_session(info->path, NULL, 1, 1, NULL); if (ret) { ERR("Session load failed: %s", error_get_str(ret)); } -end: sessiond_signal_parents(); return NULL; } diff --git a/src/bin/lttng-sessiond/load-session-thread.h b/src/bin/lttng-sessiond/load-session-thread.h index b7cd76340..aaaea9189 100644 --- a/src/bin/lttng-sessiond/load-session-thread.h +++ b/src/bin/lttng-sessiond/load-session-thread.h @@ -22,15 +22,6 @@ /* Data passed to the thread. */ struct load_session_thread_data { - /* Flag if the sem_init() has been done successfully on the sem. */ - unsigned int sem_initialized:1; - - /* - * The load session thread waits on that semaphore which the client thread - * will do a sem_post() to unblock it. - */ - sem_t message_thread_ready; - /* Path where the sessions are located. */ const char *path; }; diff --git a/src/bin/lttng-sessiond/lttng-sessiond.h b/src/bin/lttng-sessiond/lttng-sessiond.h index 9c5fcd32c..243138a9f 100644 --- a/src/bin/lttng-sessiond/lttng-sessiond.h +++ b/src/bin/lttng-sessiond/lttng-sessiond.h @@ -31,6 +31,40 @@ #include "notification-thread.h" #include "sessiond-config.h" +/* + * Consumer daemon state which is changed when spawning it, killing it or in + * case of a fatal error. + */ +enum consumerd_state { + CONSUMER_STARTED = 1, + CONSUMER_STOPPED = 2, + CONSUMER_ERROR = 3, +}; + +/* + * This consumer daemon state is used to validate if a client command will be + * able to reach the consumer. If not, the client is informed. For instance, + * doing a "lttng start" when the consumer state is set to ERROR will return an + * error to the client. + * + * The following example shows a possible race condition of this scheme: + * + * consumer thread error happens + * client cmd arrives + * client cmd checks state -> still OK + * consumer thread exit, sets error + * client cmd try to talk to consumer + * ... + * + * However, since the consumer is a different daemon, we have no way of making + * sure the command will reach it safely even with this state flag. This is why + * we consider that up to the state validation during command processing, the + * command is safe. After that, we can not guarantee the correctness of the + * client request vis-a-vis the consumer. + */ +extern enum consumerd_state ust_consumerd_state; +extern enum consumerd_state kernel_consumerd_state; + extern const char default_home_dir[], default_tracing_group[], default_ust_sock_dir[], @@ -38,6 +72,8 @@ extern const char default_home_dir[], /* Set in main.c at boot time of the daemon */ extern int kernel_tracer_fd; +extern struct lttng_kernel_tracer_version kernel_tracer_version; +extern struct lttng_kernel_tracer_abi_version kernel_tracer_abi_version; /* Notification thread handle. */ extern struct notification_thread_handle *notification_thread_handle; @@ -126,6 +162,11 @@ extern pid_t ppid; /* Internal parent PID use with daemonize. */ extern pid_t child_ppid; +/* Consumer daemon specific control data. */ +extern struct consumer_data ustconsumer32_data; +extern struct consumer_data ustconsumer64_data; +extern struct consumer_data kconsumer_data; + int sessiond_init_thread_quit_pipe(void); int sessiond_check_thread_quit_pipe(int fd, uint32_t events); int sessiond_wait_for_quit_pipe(unsigned int timeout_us); @@ -139,4 +180,6 @@ void sessiond_signal_parents(void); void sessiond_set_client_thread_state(bool running); void sessiond_wait_client_thread_stopped(void); +void *thread_manage_consumer(void *data); + #endif /* _LTT_SESSIOND_H */ diff --git a/src/bin/lttng-sessiond/main.c b/src/bin/lttng-sessiond/main.c index c82e0095b..1641ebeb8 100644 --- a/src/bin/lttng-sessiond/main.c +++ b/src/bin/lttng-sessiond/main.c @@ -50,7 +50,6 @@ #include #include #include -#include #include #include "lttng-sessiond.h" @@ -83,6 +82,7 @@ #include "sessiond-config.h" #include "timer.h" #include "thread.h" +#include "client.h" static const char *help_msg = #ifdef LTTNG_EMBED_HELP @@ -98,44 +98,6 @@ static int lockfile_fd = -1; /* Set to 1 when a SIGUSR1 signal is received. */ static int recv_child_signal; -static struct lttng_kernel_tracer_version kernel_tracer_version; -static struct lttng_kernel_tracer_abi_version kernel_tracer_abi_version; - -/* - * Consumer daemon specific control data. Every value not initialized here is - * set to 0 by the static definition. - */ -static struct consumer_data kconsumer_data = { - .type = LTTNG_CONSUMER_KERNEL, - .err_sock = -1, - .cmd_sock = -1, - .channel_monitor_pipe = -1, - .pid_mutex = PTHREAD_MUTEX_INITIALIZER, - .lock = PTHREAD_MUTEX_INITIALIZER, - .cond = PTHREAD_COND_INITIALIZER, - .cond_mutex = PTHREAD_MUTEX_INITIALIZER, -}; -static struct consumer_data ustconsumer64_data = { - .type = LTTNG_CONSUMER64_UST, - .err_sock = -1, - .cmd_sock = -1, - .channel_monitor_pipe = -1, - .pid_mutex = PTHREAD_MUTEX_INITIALIZER, - .lock = PTHREAD_MUTEX_INITIALIZER, - .cond = PTHREAD_COND_INITIALIZER, - .cond_mutex = PTHREAD_MUTEX_INITIALIZER, -}; -static struct consumer_data ustconsumer32_data = { - .type = LTTNG_CONSUMER32_UST, - .err_sock = -1, - .cmd_sock = -1, - .channel_monitor_pipe = -1, - .pid_mutex = PTHREAD_MUTEX_INITIALIZER, - .lock = PTHREAD_MUTEX_INITIALIZER, - .cond = PTHREAD_COND_INITIALIZER, - .cond_mutex = PTHREAD_MUTEX_INITIALIZER, -}; - /* Command line options */ static const struct option long_options[] = { { "client-sock", required_argument, 0, 'c' }, @@ -175,8 +137,6 @@ static const char *config_ignore_options[] = { "help", "version", "config" }; /* Shared between threads */ static int dispatch_thread_exit; -/* Sockets and FDs */ -static int client_sock = -1; static int apps_sock = -1; /* @@ -189,7 +149,6 @@ static int apps_cmd_pipe[2] = { -1, -1 }; static pthread_t apps_thread; static pthread_t apps_notify_thread; static pthread_t reg_apps_thread; -static pthread_t client_thread; static pthread_t kernel_thread; static pthread_t dispatch_thread; static pthread_t agent_reg_thread; @@ -208,40 +167,6 @@ static struct ust_cmd_queue ust_cmd_queue; static const char *module_proc_lttng = "/proc/lttng"; -/* - * Consumer daemon state which is changed when spawning it, killing it or in - * case of a fatal error. - */ -enum consumerd_state { - CONSUMER_STARTED = 1, - CONSUMER_STOPPED = 2, - CONSUMER_ERROR = 3, -}; - -/* - * This consumer daemon state is used to validate if a client command will be - * able to reach the consumer. If not, the client is informed. For instance, - * doing a "lttng start" when the consumer state is set to ERROR will return an - * error to the client. - * - * The following example shows a possible race condition of this scheme: - * - * consumer thread error happens - * client cmd arrives - * client cmd checks state -> still OK - * consumer thread exit, sets error - * client cmd try to talk to consumer - * ... - * - * However, since the consumer is a different daemon, we have no way of making - * sure the command will reach it safely even with this state flag. This is why - * we consider that up to the state validation during command processing, the - * command is safe. After that, we can not guarantee the correctness of the - * client request vis-a-vis the consumer. - */ -static enum consumerd_state ust_consumerd_state; -static enum consumerd_state kernel_consumerd_state; - /* Load session thread information to operate. */ static struct load_session_thread_data *load_info; @@ -466,39 +391,6 @@ static void sessiond_cleanup_options(void) run_as_destroy_worker(); } -/* - * Send data on a unix socket using the liblttsessiondcomm API. - * - * Return lttcomm error code. - */ -static int send_unix_sock(int sock, void *buf, size_t len) -{ - /* Check valid length */ - if (len == 0) { - return -1; - } - - return lttcomm_send_unix_sock(sock, buf, len); -} - -/* - * 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 UST applications using the shm mmap futex. */ @@ -524,62 +416,6 @@ error: return -1; } -/* - * 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 0 on success, negative value on error. - */ -static int setup_lttng_msg(struct command_ctx *cmd_ctx, - const void *payload_buf, size_t payload_len, - const void *cmd_header_buf, size_t cmd_header_len) -{ - int ret = 0; - const size_t header_len = sizeof(struct lttcomm_lttng_msg); - const size_t cmd_header_offset = header_len; - const size_t payload_offset = cmd_header_offset + cmd_header_len; - const size_t total_msg_size = header_len + cmd_header_len + payload_len; - - cmd_ctx->llm = zmalloc(total_msg_size); - - if (cmd_ctx->llm == NULL) { - PERROR("zmalloc"); - ret = -ENOMEM; - goto end; - } - - /* Copy common data */ - cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type; - cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid; - cmd_ctx->llm->cmd_header_size = cmd_header_len; - cmd_ctx->llm->data_size = payload_len; - cmd_ctx->lttng_msg_size = total_msg_size; - - /* Copy command header */ - if (cmd_header_len) { - memcpy(((uint8_t *) cmd_ctx->llm) + cmd_header_offset, cmd_header_buf, - cmd_header_len); - } - - /* Copy payload */ - if (payload_len) { - memcpy(((uint8_t *) cmd_ctx->llm) + payload_offset, payload_buf, - payload_len); - } - -end: - return ret; -} - -/* - * Version of setup_lttng_msg() without command header. - */ -static int setup_lttng_msg_no_cmd_header(struct command_ctx *cmd_ctx, - void *payload_buf, size_t payload_len) -{ - return setup_lttng_msg(cmd_ctx, payload_buf, payload_len, NULL, 0); -} /* * Update the kernel poll set of all channel fd available over all tracing * session. Add the wakeup pipe at the end of the set. @@ -939,7 +775,7 @@ static void signal_consumer_condition(struct consumer_data *data, int state) /* * This thread manage the consumer error sent back to the session daemon. */ -static void *thread_manage_consumer(void *data) +void *thread_manage_consumer(void *data) { int sock = -1, i, ret, pollfd, err = -1, should_quit = 0; uint32_t revents, nb_fd; @@ -2088,371 +1924,6 @@ error_testpoint: return NULL; } -/* - * Start the thread_manage_consumer. This must be done after a lttng-consumerd - * exec or it will fails. - */ -static int spawn_consumer_thread(struct consumer_data *consumer_data) -{ - int ret, clock_ret; - struct timespec timeout; - - /* - * Make sure we set the readiness flag to 0 because we are NOT ready. - * This access to consumer_thread_is_ready does not need to be - * protected by consumer_data.cond_mutex (yet) since the consumer - * management thread has not been started at this point. - */ - consumer_data->consumer_thread_is_ready = 0; - - /* Setup pthread condition */ - ret = pthread_condattr_init(&consumer_data->condattr); - if (ret) { - errno = ret; - PERROR("pthread_condattr_init consumer data"); - goto error; - } - - /* - * Set the monotonic clock in order to make sure we DO NOT jump in time - * between the clock_gettime() call and the timedwait call. See bug #324 - * for a more details and how we noticed it. - */ - ret = pthread_condattr_setclock(&consumer_data->condattr, CLOCK_MONOTONIC); - if (ret) { - errno = ret; - PERROR("pthread_condattr_setclock consumer data"); - goto error; - } - - ret = pthread_cond_init(&consumer_data->cond, &consumer_data->condattr); - if (ret) { - errno = ret; - PERROR("pthread_cond_init consumer data"); - goto error; - } - - ret = pthread_create(&consumer_data->thread, default_pthread_attr(), - thread_manage_consumer, consumer_data); - if (ret) { - errno = ret; - PERROR("pthread_create consumer"); - ret = -1; - goto error; - } - - /* We are about to wait on a pthread condition */ - pthread_mutex_lock(&consumer_data->cond_mutex); - - /* Get time for sem_timedwait absolute timeout */ - clock_ret = lttng_clock_gettime(CLOCK_MONOTONIC, &timeout); - /* - * Set the timeout for the condition timed wait even if the clock gettime - * call fails since we might loop on that call and we want to avoid to - * increment the timeout too many times. - */ - timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT; - - /* - * The following loop COULD be skipped in some conditions so this is why we - * set ret to 0 in order to make sure at least one round of the loop is - * done. - */ - ret = 0; - - /* - * Loop until the condition is reached or when a timeout is reached. Note - * that the pthread_cond_timedwait(P) man page specifies that EINTR can NOT - * be returned but the pthread_cond(3), from the glibc-doc, says that it is - * possible. This loop does not take any chances and works with both of - * them. - */ - while (!consumer_data->consumer_thread_is_ready && ret != ETIMEDOUT) { - if (clock_ret < 0) { - PERROR("clock_gettime spawn consumer"); - /* Infinite wait for the consumerd thread to be ready */ - ret = pthread_cond_wait(&consumer_data->cond, - &consumer_data->cond_mutex); - } else { - ret = pthread_cond_timedwait(&consumer_data->cond, - &consumer_data->cond_mutex, &timeout); - } - } - - /* Release the pthread condition */ - pthread_mutex_unlock(&consumer_data->cond_mutex); - - if (ret != 0) { - errno = ret; - if (ret == ETIMEDOUT) { - int pth_ret; - - /* - * Call has timed out so we kill the kconsumerd_thread and return - * an error. - */ - ERR("Condition timed out. The consumer thread was never ready." - " Killing it"); - pth_ret = pthread_cancel(consumer_data->thread); - if (pth_ret < 0) { - PERROR("pthread_cancel consumer thread"); - } - } else { - PERROR("pthread_cond_wait failed consumer thread"); - } - /* Caller is expecting a negative value on failure. */ - ret = -1; - goto error; - } - - pthread_mutex_lock(&consumer_data->pid_mutex); - if (consumer_data->pid == 0) { - ERR("Consumerd did not start"); - pthread_mutex_unlock(&consumer_data->pid_mutex); - goto error; - } - pthread_mutex_unlock(&consumer_data->pid_mutex); - - return 0; - -error: - return ret; -} - -/* - * Join consumer thread - */ -static int join_consumer_thread(struct consumer_data *consumer_data) -{ - void *status; - - /* Consumer pid must be a real one. */ - if (consumer_data->pid > 0) { - int ret; - ret = kill(consumer_data->pid, SIGTERM); - if (ret) { - PERROR("Error killing consumer daemon"); - return ret; - } - return pthread_join(consumer_data->thread, &status); - } else { - return 0; - } -} - -/* - * Fork and exec a consumer daemon (consumerd). - * - * Return pid if successful else -1. - */ -static pid_t spawn_consumerd(struct consumer_data *consumer_data) -{ - int ret; - pid_t pid; - const char *consumer_to_use; - const char *verbosity; - struct stat st; - - DBG("Spawning consumerd"); - - pid = fork(); - if (pid == 0) { - /* - * Exec consumerd. - */ - if (config.verbose_consumer) { - verbosity = "--verbose"; - } else if (lttng_opt_quiet) { - verbosity = "--quiet"; - } else { - verbosity = ""; - } - - switch (consumer_data->type) { - case LTTNG_CONSUMER_KERNEL: - /* - * Find out which consumerd to execute. We will first try the - * 64-bit path, then the sessiond's installation directory, and - * fallback on the 32-bit one, - */ - DBG3("Looking for a kernel consumer at these locations:"); - DBG3(" 1) %s", config.consumerd64_bin_path.value ? : "NULL"); - DBG3(" 2) %s/%s", INSTALL_BIN_PATH, DEFAULT_CONSUMERD_FILE); - DBG3(" 3) %s", config.consumerd32_bin_path.value ? : "NULL"); - if (stat(config.consumerd64_bin_path.value, &st) == 0) { - DBG3("Found location #1"); - consumer_to_use = config.consumerd64_bin_path.value; - } else if (stat(INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE, &st) == 0) { - DBG3("Found location #2"); - consumer_to_use = INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE; - } else if (config.consumerd32_bin_path.value && - stat(config.consumerd32_bin_path.value, &st) == 0) { - DBG3("Found location #3"); - consumer_to_use = config.consumerd32_bin_path.value; - } else { - DBG("Could not find any valid consumerd executable"); - ret = -EINVAL; - goto error; - } - DBG("Using kernel consumer at: %s", consumer_to_use); - (void) execl(consumer_to_use, - "lttng-consumerd", verbosity, "-k", - "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path, - "--consumerd-err-sock", consumer_data->err_unix_sock_path, - "--group", config.tracing_group_name.value, - NULL); - break; - case LTTNG_CONSUMER64_UST: - { - if (config.consumerd64_lib_dir.value) { - char *tmp; - size_t tmplen; - char *tmpnew; - - tmp = lttng_secure_getenv("LD_LIBRARY_PATH"); - if (!tmp) { - tmp = ""; - } - tmplen = strlen(config.consumerd64_lib_dir.value) + 1 /* : */ + strlen(tmp); - tmpnew = zmalloc(tmplen + 1 /* \0 */); - if (!tmpnew) { - ret = -ENOMEM; - goto error; - } - strcat(tmpnew, config.consumerd64_lib_dir.value); - if (tmp[0] != '\0') { - strcat(tmpnew, ":"); - strcat(tmpnew, tmp); - } - ret = setenv("LD_LIBRARY_PATH", tmpnew, 1); - free(tmpnew); - if (ret) { - ret = -errno; - goto error; - } - } - DBG("Using 64-bit UST consumer at: %s", config.consumerd64_bin_path.value); - (void) execl(config.consumerd64_bin_path.value, "lttng-consumerd", verbosity, "-u", - "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path, - "--consumerd-err-sock", consumer_data->err_unix_sock_path, - "--group", config.tracing_group_name.value, - NULL); - break; - } - case LTTNG_CONSUMER32_UST: - { - if (config.consumerd32_lib_dir.value) { - char *tmp; - size_t tmplen; - char *tmpnew; - - tmp = lttng_secure_getenv("LD_LIBRARY_PATH"); - if (!tmp) { - tmp = ""; - } - tmplen = strlen(config.consumerd32_lib_dir.value) + 1 /* : */ + strlen(tmp); - tmpnew = zmalloc(tmplen + 1 /* \0 */); - if (!tmpnew) { - ret = -ENOMEM; - goto error; - } - strcat(tmpnew, config.consumerd32_lib_dir.value); - if (tmp[0] != '\0') { - strcat(tmpnew, ":"); - strcat(tmpnew, tmp); - } - ret = setenv("LD_LIBRARY_PATH", tmpnew, 1); - free(tmpnew); - if (ret) { - ret = -errno; - goto error; - } - } - DBG("Using 32-bit UST consumer at: %s", config.consumerd32_bin_path.value); - (void) execl(config.consumerd32_bin_path.value, "lttng-consumerd", verbosity, "-u", - "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path, - "--consumerd-err-sock", consumer_data->err_unix_sock_path, - "--group", config.tracing_group_name.value, - NULL); - break; - } - default: - ERR("unknown consumer type"); - errno = 0; - } - if (errno != 0) { - PERROR("Consumer execl()"); - } - /* Reaching this point, we got a failure on our execl(). */ - exit(EXIT_FAILURE); - } else if (pid > 0) { - ret = pid; - } else { - PERROR("start consumer fork"); - ret = -errno; - } -error: - return ret; -} - -/* - * Spawn the consumerd daemon and session daemon thread. - */ -static int start_consumerd(struct consumer_data *consumer_data) -{ - int ret; - - /* - * Set the listen() state on the socket since there is a possible race - * between the exec() of the consumer daemon and this call if place in the - * consumer thread. See bug #366 for more details. - */ - ret = lttcomm_listen_unix_sock(consumer_data->err_sock); - if (ret < 0) { - goto error; - } - - pthread_mutex_lock(&consumer_data->pid_mutex); - if (consumer_data->pid != 0) { - pthread_mutex_unlock(&consumer_data->pid_mutex); - goto end; - } - - ret = spawn_consumerd(consumer_data); - if (ret < 0) { - ERR("Spawning consumerd failed"); - pthread_mutex_unlock(&consumer_data->pid_mutex); - goto error; - } - - /* Setting up the consumer_data pid */ - consumer_data->pid = ret; - DBG2("Consumer pid %d", consumer_data->pid); - pthread_mutex_unlock(&consumer_data->pid_mutex); - - DBG2("Spawning consumer control thread"); - ret = spawn_consumer_thread(consumer_data); - if (ret < 0) { - ERR("Fatal error spawning consumer control thread"); - goto error; - } - -end: - return 0; - -error: - /* Cleanup already created sockets on error. */ - if (consumer_data->err_sock >= 0) { - int err; - - err = close(consumer_data->err_sock); - if (err < 0) { - PERROR("close consumer data error socket"); - } - } - return ret; -} - /* * Setup necessary data for kernel tracer action. */ @@ -2528,2009 +1999,20 @@ error: } } - -/* - * Copy consumer output from the tracing session to the domain session. The - * function also applies the right modification on a per domain basis for the - * trace files destination directory. - * - * Should *NOT* be called with RCU read-side lock held. - */ -static int copy_session_consumer(int domain, struct ltt_session *session) +static int string_match(const char *str1, const char *str2) { - int ret; - const char *dir_name; - struct consumer_output *consumer; - - assert(session); - assert(session->consumer); - - switch (domain) { - case LTTNG_DOMAIN_KERNEL: - DBG3("Copying tracing session consumer output in kernel session"); - /* - * XXX: We should audit the session creation and what this function - * does "extra" in order to avoid a destroy since this function is used - * in the domain session creation (kernel and ust) only. Same for UST - * domain. - */ - if (session->kernel_session->consumer) { - consumer_output_put(session->kernel_session->consumer); - } - session->kernel_session->consumer = - consumer_copy_output(session->consumer); - /* Ease our life a bit for the next part */ - consumer = session->kernel_session->consumer; - dir_name = DEFAULT_KERNEL_TRACE_DIR; - break; - case LTTNG_DOMAIN_JUL: - case LTTNG_DOMAIN_LOG4J: - case LTTNG_DOMAIN_PYTHON: - case LTTNG_DOMAIN_UST: - DBG3("Copying tracing session consumer output in UST session"); - if (session->ust_session->consumer) { - consumer_output_put(session->ust_session->consumer); - } - session->ust_session->consumer = - consumer_copy_output(session->consumer); - /* Ease our life a bit for the next part */ - consumer = session->ust_session->consumer; - dir_name = DEFAULT_UST_TRACE_DIR; - break; - default: - ret = LTTNG_ERR_UNKNOWN_DOMAIN; - goto error; - } - - /* Append correct directory to subdir */ - strncat(consumer->subdir, dir_name, - sizeof(consumer->subdir) - strlen(consumer->subdir) - 1); - DBG3("Copy session consumer subdir %s", consumer->subdir); - - ret = LTTNG_OK; - -error: - return ret; + return (str1 && str2) && !strcmp(str1, str2); } /* - * Create an UST session and add it to the session ust list. + * Take an option from the getopt output and set it in the right variable to be + * used later. * - * Should *NOT* be called with RCU read-side lock held. + * Return 0 on success else a negative value. */ -static int create_ust_session(struct ltt_session *session, - struct lttng_domain *domain) +static int set_option(int opt, const char *arg, const char *optname) { - int ret; - struct ltt_ust_session *lus = NULL; - - assert(session); - assert(domain); - assert(session->consumer); - - switch (domain->type) { - case LTTNG_DOMAIN_JUL: - case LTTNG_DOMAIN_LOG4J: - case LTTNG_DOMAIN_PYTHON: - case LTTNG_DOMAIN_UST: - break; - default: - ERR("Unknown UST domain on create session %d", domain->type); - ret = LTTNG_ERR_UNKNOWN_DOMAIN; - goto error; - } - - DBG("Creating UST session"); - - lus = trace_ust_create_session(session->id); - if (lus == NULL) { - ret = LTTNG_ERR_UST_SESS_FAIL; - goto error; - } - - lus->uid = session->uid; - lus->gid = session->gid; - lus->output_traces = session->output_traces; - lus->snapshot_mode = session->snapshot_mode; - lus->live_timer_interval = session->live_timer; - session->ust_session = lus; - if (session->shm_path[0]) { - strncpy(lus->root_shm_path, session->shm_path, - sizeof(lus->root_shm_path)); - lus->root_shm_path[sizeof(lus->root_shm_path) - 1] = '\0'; - strncpy(lus->shm_path, session->shm_path, - sizeof(lus->shm_path)); - lus->shm_path[sizeof(lus->shm_path) - 1] = '\0'; - strncat(lus->shm_path, "/ust", - sizeof(lus->shm_path) - strlen(lus->shm_path) - 1); - } - /* Copy session output to the newly created UST session */ - ret = copy_session_consumer(domain->type, session); - if (ret != LTTNG_OK) { - goto error; - } - - return LTTNG_OK; - -error: - free(lus); - session->ust_session = NULL; - return ret; -} - -/* - * 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 = LTTNG_ERR_KERN_SESS_FAIL; - goto error; - } - - /* Code flow safety */ - assert(session->kernel_session); - - /* Copy session output to the newly created Kernel session */ - ret = copy_session_consumer(LTTNG_DOMAIN_KERNEL, session); - if (ret != LTTNG_OK) { - goto error; - } - - session->kernel_session->uid = session->uid; - session->kernel_session->gid = session->gid; - session->kernel_session->output_traces = session->output_traces; - session->kernel_session->snapshot_mode = session->snapshot_mode; - - return LTTNG_OK; - -error: - trace_kernel_destroy_session(session->kernel_session); - session->kernel_session = NULL; - return ret; -} - -/* - * Count number of session permitted by uid/gid. - */ -static unsigned int lttng_sessions_count(uid_t uid, gid_t gid) -{ - unsigned int i = 0; - struct ltt_session *session; - const struct ltt_session_list *session_list = session_get_list(); - - DBG("Counting number of available session for UID %d GID %d", - uid, gid); - cds_list_for_each_entry(session, &session_list->head, list) { - if (!session_get(session)) { - continue; - } - session_lock(session); - /* Only count the sessions the user can control. */ - if (session_access_ok(session, uid, gid) && - !session->destroyed) { - i++; - } - session_unlock(session); - session_put(session); - } - return i; -} - -static int receive_userspace_probe(struct command_ctx *cmd_ctx, int sock, - int *sock_error, struct lttng_event *event) -{ - int fd, ret; - struct lttng_userspace_probe_location *probe_location; - const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; - struct lttng_dynamic_buffer probe_location_buffer; - struct lttng_buffer_view buffer_view; - - /* - * Create a buffer to store the serialized version of the probe - * location. - */ - lttng_dynamic_buffer_init(&probe_location_buffer); - ret = lttng_dynamic_buffer_set_size(&probe_location_buffer, - cmd_ctx->lsm->u.enable.userspace_probe_location_len); - if (ret) { - ret = LTTNG_ERR_NOMEM; - goto error; - } - - /* - * Receive the probe location. - */ - ret = lttcomm_recv_unix_sock(sock, probe_location_buffer.data, - probe_location_buffer.size); - if (ret <= 0) { - DBG("Nothing recv() from client var len data... continuing"); - *sock_error = 1; - lttng_dynamic_buffer_reset(&probe_location_buffer); - ret = LTTNG_ERR_PROBE_LOCATION_INVAL; - goto error; - } - - buffer_view = lttng_buffer_view_from_dynamic_buffer( - &probe_location_buffer, 0, probe_location_buffer.size); - - /* - * Extract the probe location from the serialized version. - */ - ret = lttng_userspace_probe_location_create_from_buffer( - &buffer_view, &probe_location); - if (ret < 0) { - WARN("Failed to create a userspace probe location from the received buffer"); - lttng_dynamic_buffer_reset( &probe_location_buffer); - ret = LTTNG_ERR_PROBE_LOCATION_INVAL; - goto error; - } - - /* - * Receive the file descriptor to the target binary from the client. - */ - DBG("Receiving userspace probe target FD from client ..."); - ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1); - if (ret <= 0) { - DBG("Nothing recv() from client userspace probe fd... continuing"); - *sock_error = 1; - ret = LTTNG_ERR_PROBE_LOCATION_INVAL; - goto error; - } - - /* - * Set the file descriptor received from the client through the unix - * socket in the probe location. - */ - lookup = lttng_userspace_probe_location_get_lookup_method(probe_location); - if (!lookup) { - ret = LTTNG_ERR_PROBE_LOCATION_INVAL; - goto error; - } - - /* - * From the kernel tracer's perspective, all userspace probe event types - * are all the same: a file and an offset. - */ - switch (lttng_userspace_probe_location_lookup_method_get_type(lookup)) { - case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF: - ret = lttng_userspace_probe_location_function_set_binary_fd( - probe_location, fd); - break; - case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT: - ret = lttng_userspace_probe_location_tracepoint_set_binary_fd( - probe_location, fd); - break; - default: - ret = LTTNG_ERR_PROBE_LOCATION_INVAL; - goto error; - } - - if (ret) { - ret = LTTNG_ERR_PROBE_LOCATION_INVAL; - goto error; - } - - /* Attach the probe location to the event. */ - ret = lttng_event_set_userspace_probe_location(event, probe_location); - if (ret) { - ret = LTTNG_ERR_PROBE_LOCATION_INVAL; - goto error; - } - - lttng_dynamic_buffer_reset(&probe_location_buffer); -error: - return ret; -} - -/* - * Check if the current kernel tracer supports the session rotation feature. - * Return 1 if it does, 0 otherwise. - */ -static int check_rotate_compatible(void) -{ - int ret = 1; - - if (kernel_tracer_version.major != 2 || kernel_tracer_version.minor < 11) { - DBG("Kernel tracer version is not compatible with the rotation feature"); - ret = 0; - } - - return ret; -} - -/* - * Process the command requested by the lttng client within the command - * context structure. This function make sure that the return structure (llm) - * is set and ready for transmission before returning. - * - * Return any error encountered or 0 for success. - * - * "sock" is only used for special-case var. len data. - * - * Should *NOT* be called with RCU read-side lock held. - */ -static int process_client_msg(struct command_ctx *cmd_ctx, int sock, - int *sock_error) -{ - int ret = LTTNG_OK; - int need_tracing_session = 1; - int need_domain; - - DBG("Processing client command %d", cmd_ctx->lsm->cmd_type); - - assert(!rcu_read_ongoing()); - - *sock_error = 0; - - switch (cmd_ctx->lsm->cmd_type) { - case LTTNG_CREATE_SESSION: - case LTTNG_CREATE_SESSION_SNAPSHOT: - case LTTNG_CREATE_SESSION_LIVE: - case LTTNG_DESTROY_SESSION: - case LTTNG_LIST_SESSIONS: - case LTTNG_LIST_DOMAINS: - case LTTNG_START_TRACE: - case LTTNG_STOP_TRACE: - case LTTNG_DATA_PENDING: - case LTTNG_SNAPSHOT_ADD_OUTPUT: - case LTTNG_SNAPSHOT_DEL_OUTPUT: - case LTTNG_SNAPSHOT_LIST_OUTPUT: - case LTTNG_SNAPSHOT_RECORD: - case LTTNG_SAVE_SESSION: - case LTTNG_SET_SESSION_SHM_PATH: - case LTTNG_REGENERATE_METADATA: - case LTTNG_REGENERATE_STATEDUMP: - case LTTNG_REGISTER_TRIGGER: - case LTTNG_UNREGISTER_TRIGGER: - case LTTNG_ROTATE_SESSION: - case LTTNG_ROTATION_GET_INFO: - case LTTNG_ROTATION_SET_SCHEDULE: - case LTTNG_SESSION_LIST_ROTATION_SCHEDULES: - need_domain = 0; - break; - default: - need_domain = 1; - } - - if (config.no_kernel && need_domain - && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) { - if (!is_root) { - ret = LTTNG_ERR_NEED_ROOT_SESSIOND; - } else { - ret = LTTNG_ERR_KERN_NA; - } - goto error; - } - - /* Deny register consumer if we already have a spawned consumer. */ - if (cmd_ctx->lsm->cmd_type == LTTNG_REGISTER_CONSUMER) { - pthread_mutex_lock(&kconsumer_data.pid_mutex); - if (kconsumer_data.pid > 0) { - ret = LTTNG_ERR_KERN_CONSUMER_FAIL; - pthread_mutex_unlock(&kconsumer_data.pid_mutex); - goto error; - } - pthread_mutex_unlock(&kconsumer_data.pid_mutex); - } - - /* - * Check for command that don't needs to allocate a returned payload. We do - * this here so we don't have to make the call for no payload at each - * command. - */ - switch(cmd_ctx->lsm->cmd_type) { - case LTTNG_LIST_SESSIONS: - case LTTNG_LIST_TRACEPOINTS: - case LTTNG_LIST_TRACEPOINT_FIELDS: - case LTTNG_LIST_DOMAINS: - case LTTNG_LIST_CHANNELS: - case LTTNG_LIST_EVENTS: - case LTTNG_LIST_SYSCALLS: - case LTTNG_LIST_TRACKER_PIDS: - case LTTNG_DATA_PENDING: - case LTTNG_ROTATE_SESSION: - case LTTNG_ROTATION_GET_INFO: - case LTTNG_SESSION_LIST_ROTATION_SCHEDULES: - break; - default: - /* Setup lttng message with no payload */ - ret = setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0); - if (ret < 0) { - /* This label does not try to unlock the session */ - goto init_setup_error; - } - } - - /* Commands that DO NOT need a session. */ - switch (cmd_ctx->lsm->cmd_type) { - case LTTNG_CREATE_SESSION: - case LTTNG_CREATE_SESSION_SNAPSHOT: - case LTTNG_CREATE_SESSION_LIVE: - case LTTNG_LIST_SESSIONS: - case LTTNG_LIST_TRACEPOINTS: - case LTTNG_LIST_SYSCALLS: - case LTTNG_LIST_TRACEPOINT_FIELDS: - case LTTNG_SAVE_SESSION: - case LTTNG_REGISTER_TRIGGER: - case LTTNG_UNREGISTER_TRIGGER: - need_tracing_session = 0; - break; - default: - DBG("Getting session %s by name", cmd_ctx->lsm->session.name); - /* - * We keep the session list lock across _all_ commands - * for now, because the per-session lock does not - * handle teardown properly. - */ - session_lock_list(); - cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name); - if (cmd_ctx->session == NULL) { - ret = LTTNG_ERR_SESS_NOT_FOUND; - goto error; - } else { - /* Acquire lock for the session */ - session_lock(cmd_ctx->session); - } - break; - } - - /* - * Commands that need a valid session but should NOT create one if none - * exists. Instead of creating one and destroying it when the command is - * handled, process that right before so we save some round trip in useless - * code path. - */ - switch (cmd_ctx->lsm->cmd_type) { - case LTTNG_DISABLE_CHANNEL: - case LTTNG_DISABLE_EVENT: - switch (cmd_ctx->lsm->domain.type) { - case LTTNG_DOMAIN_KERNEL: - if (!cmd_ctx->session->kernel_session) { - ret = LTTNG_ERR_NO_CHANNEL; - goto error; - } - break; - case LTTNG_DOMAIN_JUL: - case LTTNG_DOMAIN_LOG4J: - case LTTNG_DOMAIN_PYTHON: - case LTTNG_DOMAIN_UST: - if (!cmd_ctx->session->ust_session) { - ret = LTTNG_ERR_NO_CHANNEL; - goto error; - } - break; - default: - ret = LTTNG_ERR_UNKNOWN_DOMAIN; - goto error; - } - default: - break; - } - - if (!need_domain) { - goto skip_domain; - } - - /* - * Check domain type for specific "pre-action". - */ - switch (cmd_ctx->lsm->domain.type) { - case LTTNG_DOMAIN_KERNEL: - if (!is_root) { - ret = LTTNG_ERR_NEED_ROOT_SESSIOND; - goto error; - } - - /* Kernel tracer check */ - if (kernel_tracer_fd == -1) { - /* Basically, load kernel tracer modules */ - ret = init_kernel_tracer(); - if (ret != 0) { - goto error; - } - } - - /* Consumer is in an ERROR state. Report back to client */ - if (uatomic_read(&kernel_consumerd_state) == CONSUMER_ERROR) { - ret = LTTNG_ERR_NO_KERNCONSUMERD; - goto error; - } - - /* Need a session for kernel command */ - if (need_tracing_session) { - if (cmd_ctx->session->kernel_session == NULL) { - ret = create_kernel_session(cmd_ctx->session); - if (ret < 0) { - ret = LTTNG_ERR_KERN_SESS_FAIL; - goto error; - } - } - - /* Start the kernel consumer daemon */ - pthread_mutex_lock(&kconsumer_data.pid_mutex); - if (kconsumer_data.pid == 0 && - cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) { - pthread_mutex_unlock(&kconsumer_data.pid_mutex); - ret = start_consumerd(&kconsumer_data); - if (ret < 0) { - ret = LTTNG_ERR_KERN_CONSUMER_FAIL; - goto error; - } - uatomic_set(&kernel_consumerd_state, CONSUMER_STARTED); - } else { - pthread_mutex_unlock(&kconsumer_data.pid_mutex); - } - - /* - * The consumer was just spawned so we need to add the socket to - * the consumer output of the session if exist. - */ - ret = consumer_create_socket(&kconsumer_data, - cmd_ctx->session->kernel_session->consumer); - if (ret < 0) { - goto error; - } - } - - break; - case LTTNG_DOMAIN_JUL: - case LTTNG_DOMAIN_LOG4J: - case LTTNG_DOMAIN_PYTHON: - case LTTNG_DOMAIN_UST: - { - if (!ust_app_supported()) { - ret = LTTNG_ERR_NO_UST; - goto error; - } - /* Consumer is in an ERROR state. Report back to client */ - if (uatomic_read(&ust_consumerd_state) == CONSUMER_ERROR) { - ret = LTTNG_ERR_NO_USTCONSUMERD; - goto error; - } - - if (need_tracing_session) { - /* Create UST session if none exist. */ - if (cmd_ctx->session->ust_session == NULL) { - ret = create_ust_session(cmd_ctx->session, - &cmd_ctx->lsm->domain); - if (ret != LTTNG_OK) { - goto error; - } - } - - /* Start the UST consumer daemons */ - /* 64-bit */ - pthread_mutex_lock(&ustconsumer64_data.pid_mutex); - if (config.consumerd64_bin_path.value && - ustconsumer64_data.pid == 0 && - cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) { - pthread_mutex_unlock(&ustconsumer64_data.pid_mutex); - ret = start_consumerd(&ustconsumer64_data); - if (ret < 0) { - ret = LTTNG_ERR_UST_CONSUMER64_FAIL; - uatomic_set(&ust_consumerd64_fd, -EINVAL); - goto error; - } - - uatomic_set(&ust_consumerd64_fd, ustconsumer64_data.cmd_sock); - uatomic_set(&ust_consumerd_state, CONSUMER_STARTED); - } else { - pthread_mutex_unlock(&ustconsumer64_data.pid_mutex); - } - - /* - * Setup socket for consumer 64 bit. No need for atomic access - * since it was set above and can ONLY be set in this thread. - */ - ret = consumer_create_socket(&ustconsumer64_data, - cmd_ctx->session->ust_session->consumer); - if (ret < 0) { - goto error; - } - - /* 32-bit */ - pthread_mutex_lock(&ustconsumer32_data.pid_mutex); - if (config.consumerd32_bin_path.value && - ustconsumer32_data.pid == 0 && - cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) { - pthread_mutex_unlock(&ustconsumer32_data.pid_mutex); - ret = start_consumerd(&ustconsumer32_data); - if (ret < 0) { - ret = LTTNG_ERR_UST_CONSUMER32_FAIL; - uatomic_set(&ust_consumerd32_fd, -EINVAL); - goto error; - } - - uatomic_set(&ust_consumerd32_fd, ustconsumer32_data.cmd_sock); - uatomic_set(&ust_consumerd_state, CONSUMER_STARTED); - } else { - pthread_mutex_unlock(&ustconsumer32_data.pid_mutex); - } - - /* - * Setup socket for consumer 32 bit. No need for atomic access - * since it was set above and can ONLY be set in this thread. - */ - ret = consumer_create_socket(&ustconsumer32_data, - cmd_ctx->session->ust_session->consumer); - if (ret < 0) { - goto error; - } - } - break; - } - default: - break; - } -skip_domain: - - /* Validate consumer daemon state when start/stop trace command */ - if (cmd_ctx->lsm->cmd_type == LTTNG_START_TRACE || - cmd_ctx->lsm->cmd_type == LTTNG_STOP_TRACE) { - switch (cmd_ctx->lsm->domain.type) { - case LTTNG_DOMAIN_NONE: - break; - case LTTNG_DOMAIN_JUL: - case LTTNG_DOMAIN_LOG4J: - case LTTNG_DOMAIN_PYTHON: - case LTTNG_DOMAIN_UST: - if (uatomic_read(&ust_consumerd_state) != CONSUMER_STARTED) { - ret = LTTNG_ERR_NO_USTCONSUMERD; - goto error; - } - break; - case LTTNG_DOMAIN_KERNEL: - if (uatomic_read(&kernel_consumerd_state) != CONSUMER_STARTED) { - ret = LTTNG_ERR_NO_KERNCONSUMERD; - goto error; - } - break; - default: - ret = LTTNG_ERR_UNKNOWN_DOMAIN; - goto error; - } - } - - /* - * Check that the UID or GID match that of the tracing session. - * The root user can interact with all sessions. - */ - if (need_tracing_session) { - if (!session_access_ok(cmd_ctx->session, - LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds), - LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds)) || - cmd_ctx->session->destroyed) { - ret = LTTNG_ERR_EPERM; - goto error; - } - } - - /* - * Send relayd information to consumer as soon as we have a domain and a - * session defined. - */ - if (cmd_ctx->session && need_domain) { - /* - * Setup relayd if not done yet. If the relayd information was already - * sent to the consumer, this call will gracefully return. - */ - ret = cmd_setup_relayd(cmd_ctx->session); - if (ret != LTTNG_OK) { - goto error; - } - } - - /* Process by command type */ - switch (cmd_ctx->lsm->cmd_type) { - case LTTNG_ADD_CONTEXT: - { - /* - * An LTTNG_ADD_CONTEXT command might have a supplementary - * payload if the context being added is an application context. - */ - if (cmd_ctx->lsm->u.context.ctx.ctx == - LTTNG_EVENT_CONTEXT_APP_CONTEXT) { - char *provider_name = NULL, *context_name = NULL; - size_t provider_name_len = - cmd_ctx->lsm->u.context.provider_name_len; - size_t context_name_len = - cmd_ctx->lsm->u.context.context_name_len; - - if (provider_name_len == 0 || context_name_len == 0) { - /* - * Application provider and context names MUST - * be provided. - */ - ret = -LTTNG_ERR_INVALID; - goto error; - } - - provider_name = zmalloc(provider_name_len + 1); - if (!provider_name) { - ret = -LTTNG_ERR_NOMEM; - goto error; - } - cmd_ctx->lsm->u.context.ctx.u.app_ctx.provider_name = - provider_name; - - context_name = zmalloc(context_name_len + 1); - if (!context_name) { - ret = -LTTNG_ERR_NOMEM; - goto error_add_context; - } - cmd_ctx->lsm->u.context.ctx.u.app_ctx.ctx_name = - context_name; - - ret = lttcomm_recv_unix_sock(sock, provider_name, - provider_name_len); - if (ret < 0) { - goto error_add_context; - } - - ret = lttcomm_recv_unix_sock(sock, context_name, - context_name_len); - if (ret < 0) { - goto error_add_context; - } - } - - /* - * cmd_add_context assumes ownership of the provider and context - * names. - */ - ret = cmd_add_context(cmd_ctx->session, - cmd_ctx->lsm->domain.type, - cmd_ctx->lsm->u.context.channel_name, - &cmd_ctx->lsm->u.context.ctx, - kernel_poll_pipe[1]); - - cmd_ctx->lsm->u.context.ctx.u.app_ctx.provider_name = NULL; - cmd_ctx->lsm->u.context.ctx.u.app_ctx.ctx_name = NULL; -error_add_context: - free(cmd_ctx->lsm->u.context.ctx.u.app_ctx.provider_name); - free(cmd_ctx->lsm->u.context.ctx.u.app_ctx.ctx_name); - if (ret < 0) { - goto error; - } - break; - } - case LTTNG_DISABLE_CHANNEL: - { - ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type, - cmd_ctx->lsm->u.disable.channel_name); - break; - } - case LTTNG_DISABLE_EVENT: - { - - /* - * FIXME: handle filter; for now we just receive the filter's - * bytecode along with the filter expression which are sent by - * liblttng-ctl and discard them. - * - * This fixes an issue where the client may block while sending - * the filter payload and encounter an error because the session - * daemon closes the socket without ever handling this data. - */ - size_t count = cmd_ctx->lsm->u.disable.expression_len + - cmd_ctx->lsm->u.disable.bytecode_len; - - if (count) { - char data[LTTNG_FILTER_MAX_LEN]; - - DBG("Discarding disable event command payload of size %zu", count); - while (count) { - ret = lttcomm_recv_unix_sock(sock, data, - count > sizeof(data) ? sizeof(data) : count); - if (ret < 0) { - goto error; - } - - count -= (size_t) ret; - } - } - /* FIXME: passing packed structure to non-packed pointer */ - ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type, - cmd_ctx->lsm->u.disable.channel_name, - &cmd_ctx->lsm->u.disable.event); - break; - } - case LTTNG_ENABLE_CHANNEL: - { - cmd_ctx->lsm->u.channel.chan.attr.extended.ptr = - (struct lttng_channel_extended *) &cmd_ctx->lsm->u.channel.extended; - ret = cmd_enable_channel(cmd_ctx->session, &cmd_ctx->lsm->domain, - &cmd_ctx->lsm->u.channel.chan, - kernel_poll_pipe[1]); - break; - } - case LTTNG_TRACK_PID: - { - ret = cmd_track_pid(cmd_ctx->session, - cmd_ctx->lsm->domain.type, - cmd_ctx->lsm->u.pid_tracker.pid); - break; - } - case LTTNG_UNTRACK_PID: - { - ret = cmd_untrack_pid(cmd_ctx->session, - cmd_ctx->lsm->domain.type, - cmd_ctx->lsm->u.pid_tracker.pid); - break; - } - case LTTNG_ENABLE_EVENT: - { - struct lttng_event *ev = NULL; - struct lttng_event_exclusion *exclusion = NULL; - struct lttng_filter_bytecode *bytecode = NULL; - char *filter_expression = NULL; - - /* Handle exclusion events and receive it from the client. */ - if (cmd_ctx->lsm->u.enable.exclusion_count > 0) { - size_t count = cmd_ctx->lsm->u.enable.exclusion_count; - - exclusion = zmalloc(sizeof(struct lttng_event_exclusion) + - (count * LTTNG_SYMBOL_NAME_LEN)); - if (!exclusion) { - ret = LTTNG_ERR_EXCLUSION_NOMEM; - goto error; - } - - DBG("Receiving var len exclusion event list from client ..."); - exclusion->count = count; - ret = lttcomm_recv_unix_sock(sock, exclusion->names, - count * LTTNG_SYMBOL_NAME_LEN); - if (ret <= 0) { - DBG("Nothing recv() from client var len data... continuing"); - *sock_error = 1; - free(exclusion); - ret = LTTNG_ERR_EXCLUSION_INVAL; - goto error; - } - } - - /* Get filter expression from client. */ - if (cmd_ctx->lsm->u.enable.expression_len > 0) { - size_t expression_len = - cmd_ctx->lsm->u.enable.expression_len; - - if (expression_len > LTTNG_FILTER_MAX_LEN) { - ret = LTTNG_ERR_FILTER_INVAL; - free(exclusion); - goto error; - } - - filter_expression = zmalloc(expression_len); - if (!filter_expression) { - free(exclusion); - ret = LTTNG_ERR_FILTER_NOMEM; - goto error; - } - - /* Receive var. len. data */ - DBG("Receiving var len filter's expression from client ..."); - ret = lttcomm_recv_unix_sock(sock, filter_expression, - expression_len); - if (ret <= 0) { - DBG("Nothing recv() from client var len data... continuing"); - *sock_error = 1; - free(filter_expression); - free(exclusion); - ret = LTTNG_ERR_FILTER_INVAL; - goto error; - } - } - - /* Handle filter and get bytecode from client. */ - if (cmd_ctx->lsm->u.enable.bytecode_len > 0) { - size_t bytecode_len = cmd_ctx->lsm->u.enable.bytecode_len; - - if (bytecode_len > LTTNG_FILTER_MAX_LEN) { - ret = LTTNG_ERR_FILTER_INVAL; - free(filter_expression); - free(exclusion); - goto error; - } - - bytecode = zmalloc(bytecode_len); - if (!bytecode) { - free(filter_expression); - free(exclusion); - ret = LTTNG_ERR_FILTER_NOMEM; - goto error; - } - - /* Receive var. len. data */ - DBG("Receiving var len filter's bytecode from client ..."); - ret = lttcomm_recv_unix_sock(sock, bytecode, bytecode_len); - if (ret <= 0) { - DBG("Nothing recv() from client var len data... continuing"); - *sock_error = 1; - free(filter_expression); - free(bytecode); - free(exclusion); - ret = LTTNG_ERR_FILTER_INVAL; - goto error; - } - - if ((bytecode->len + sizeof(*bytecode)) != bytecode_len) { - free(filter_expression); - free(bytecode); - free(exclusion); - ret = LTTNG_ERR_FILTER_INVAL; - goto error; - } - } - - ev = lttng_event_copy(&cmd_ctx->lsm->u.enable.event); - if (!ev) { - DBG("Failed to copy event: %s", - cmd_ctx->lsm->u.enable.event.name); - free(filter_expression); - free(bytecode); - free(exclusion); - ret = LTTNG_ERR_NOMEM; - goto error; - } - - - if (cmd_ctx->lsm->u.enable.userspace_probe_location_len > 0) { - /* Expect a userspace probe description. */ - ret = receive_userspace_probe(cmd_ctx, sock, sock_error, ev); - if (ret) { - free(filter_expression); - free(bytecode); - free(exclusion); - lttng_event_destroy(ev); - goto error; - } - } - - ret = cmd_enable_event(cmd_ctx->session, &cmd_ctx->lsm->domain, - cmd_ctx->lsm->u.enable.channel_name, - ev, - filter_expression, bytecode, exclusion, - kernel_poll_pipe[1]); - lttng_event_destroy(ev); - break; - } - case LTTNG_LIST_TRACEPOINTS: - { - struct lttng_event *events; - ssize_t nb_events; - - session_lock_list(); - nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events); - session_unlock_list(); - if (nb_events < 0) { - /* Return value is a negative lttng_error_code. */ - ret = -nb_events; - 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_no_cmd_header(cmd_ctx, events, - sizeof(struct lttng_event) * nb_events); - free(events); - - if (ret < 0) { - goto setup_error; - } - - ret = LTTNG_OK; - break; - } - case LTTNG_LIST_TRACEPOINT_FIELDS: - { - struct lttng_event_field *fields; - ssize_t nb_fields; - - session_lock_list(); - nb_fields = cmd_list_tracepoint_fields(cmd_ctx->lsm->domain.type, - &fields); - session_unlock_list(); - if (nb_fields < 0) { - /* Return value is a negative lttng_error_code. */ - ret = -nb_fields; - 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_no_cmd_header(cmd_ctx, fields, - sizeof(struct lttng_event_field) * nb_fields); - free(fields); - - if (ret < 0) { - goto setup_error; - } - - ret = LTTNG_OK; - break; - } - case LTTNG_LIST_SYSCALLS: - { - struct lttng_event *events; - ssize_t nb_events; - - nb_events = cmd_list_syscalls(&events); - if (nb_events < 0) { - /* Return value is a negative lttng_error_code. */ - ret = -nb_events; - 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_no_cmd_header(cmd_ctx, events, - sizeof(struct lttng_event) * nb_events); - free(events); - - if (ret < 0) { - goto setup_error; - } - - ret = LTTNG_OK; - break; - } - case LTTNG_LIST_TRACKER_PIDS: - { - int32_t *pids = NULL; - ssize_t nr_pids; - - nr_pids = cmd_list_tracker_pids(cmd_ctx->session, - cmd_ctx->lsm->domain.type, &pids); - if (nr_pids < 0) { - /* Return value is a negative lttng_error_code. */ - ret = -nr_pids; - 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_no_cmd_header(cmd_ctx, pids, - sizeof(int32_t) * nr_pids); - free(pids); - - if (ret < 0) { - goto setup_error; - } - - ret = LTTNG_OK; - break; - } - case LTTNG_SET_CONSUMER_URI: - { - size_t nb_uri, len; - struct lttng_uri *uris; - - nb_uri = cmd_ctx->lsm->u.uri.size; - len = nb_uri * sizeof(struct lttng_uri); - - if (nb_uri == 0) { - ret = LTTNG_ERR_INVALID; - goto error; - } - - uris = zmalloc(len); - if (uris == NULL) { - ret = LTTNG_ERR_FATAL; - goto error; - } - - /* Receive variable len data */ - DBG("Receiving %zu URI(s) from client ...", nb_uri); - ret = lttcomm_recv_unix_sock(sock, uris, len); - if (ret <= 0) { - DBG("No URIs received from client... continuing"); - *sock_error = 1; - ret = LTTNG_ERR_SESSION_FAIL; - free(uris); - goto error; - } - - ret = cmd_set_consumer_uri(cmd_ctx->session, nb_uri, uris); - free(uris); - if (ret != LTTNG_OK) { - goto error; - } - - - break; - } - case LTTNG_START_TRACE: - { - /* - * On the first start, if we have a kernel session and we have - * enabled time or size-based rotations, we have to make sure - * the kernel tracer supports it. - */ - if (!cmd_ctx->session->has_been_started && \ - cmd_ctx->session->kernel_session && \ - (cmd_ctx->session->rotate_timer_period || \ - cmd_ctx->session->rotate_size) && \ - !check_rotate_compatible()) { - DBG("Kernel tracer version is not compatible with the rotation feature"); - ret = LTTNG_ERR_ROTATION_WRONG_VERSION; - goto error; - } - ret = cmd_start_trace(cmd_ctx->session); - break; - } - case LTTNG_STOP_TRACE: - { - ret = cmd_stop_trace(cmd_ctx->session); - break; - } - case LTTNG_CREATE_SESSION: - { - size_t nb_uri, len; - struct lttng_uri *uris = NULL; - - nb_uri = cmd_ctx->lsm->u.uri.size; - len = nb_uri * sizeof(struct lttng_uri); - - if (nb_uri > 0) { - uris = zmalloc(len); - if (uris == NULL) { - ret = LTTNG_ERR_FATAL; - goto error; - } - - /* Receive variable len data */ - DBG("Waiting for %zu URIs from client ...", nb_uri); - ret = lttcomm_recv_unix_sock(sock, uris, len); - if (ret <= 0) { - DBG("No URIs received from client... continuing"); - *sock_error = 1; - ret = LTTNG_ERR_SESSION_FAIL; - free(uris); - goto error; - } - - if (nb_uri == 1 && uris[0].dtype != LTTNG_DST_PATH) { - DBG("Creating session with ONE network URI is a bad call"); - ret = LTTNG_ERR_SESSION_FAIL; - free(uris); - goto error; - } - } - - ret = cmd_create_session_uri(cmd_ctx->lsm->session.name, uris, nb_uri, - &cmd_ctx->creds, 0); - - free(uris); - - break; - } - case LTTNG_DESTROY_SESSION: - { - ret = cmd_destroy_session(cmd_ctx->session, - notification_thread_handle); - break; - } - case LTTNG_LIST_DOMAINS: - { - ssize_t nb_dom; - struct lttng_domain *domains = NULL; - - nb_dom = cmd_list_domains(cmd_ctx->session, &domains); - if (nb_dom < 0) { - /* Return value is a negative lttng_error_code. */ - ret = -nb_dom; - goto error; - } - - ret = setup_lttng_msg_no_cmd_header(cmd_ctx, domains, - nb_dom * sizeof(struct lttng_domain)); - free(domains); - - if (ret < 0) { - goto setup_error; - } - - ret = LTTNG_OK; - break; - } - case LTTNG_LIST_CHANNELS: - { - ssize_t payload_size; - struct lttng_channel *channels = NULL; - - payload_size = cmd_list_channels(cmd_ctx->lsm->domain.type, - cmd_ctx->session, &channels); - if (payload_size < 0) { - /* Return value is a negative lttng_error_code. */ - ret = -payload_size; - goto error; - } - - ret = setup_lttng_msg_no_cmd_header(cmd_ctx, channels, - payload_size); - free(channels); - - if (ret < 0) { - goto setup_error; - } - - ret = LTTNG_OK; - break; - } - case LTTNG_LIST_EVENTS: - { - ssize_t nb_event; - struct lttng_event *events = NULL; - struct lttcomm_event_command_header cmd_header; - size_t total_size; - - memset(&cmd_header, 0, sizeof(cmd_header)); - /* Extended infos are included at the end of events */ - nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, - cmd_ctx->session, cmd_ctx->lsm->u.list.channel_name, - &events, &total_size); - - if (nb_event < 0) { - /* Return value is a negative lttng_error_code. */ - ret = -nb_event; - goto error; - } - - cmd_header.nb_events = nb_event; - ret = setup_lttng_msg(cmd_ctx, events, total_size, - &cmd_header, sizeof(cmd_header)); - free(events); - - if (ret < 0) { - goto setup_error; - } - - ret = LTTNG_OK; - break; - } - case LTTNG_LIST_SESSIONS: - { - unsigned int nr_sessions; - void *sessions_payload; - size_t payload_len; - - session_lock_list(); - nr_sessions = lttng_sessions_count( - LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds), - LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds)); - payload_len = sizeof(struct lttng_session) * nr_sessions; - sessions_payload = zmalloc(payload_len); - - if (!sessions_payload) { - session_unlock_list(); - ret = -ENOMEM; - goto setup_error; - } - - cmd_list_lttng_sessions(sessions_payload, - LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds), - LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds)); - session_unlock_list(); - - ret = setup_lttng_msg_no_cmd_header(cmd_ctx, sessions_payload, - payload_len); - free(sessions_payload); - - if (ret < 0) { - goto setup_error; - } - - ret = LTTNG_OK; - break; - } - case LTTNG_REGISTER_CONSUMER: - { - struct consumer_data *cdata; - - switch (cmd_ctx->lsm->domain.type) { - case LTTNG_DOMAIN_KERNEL: - cdata = &kconsumer_data; - break; - default: - ret = LTTNG_ERR_UND; - goto error; - } - - ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type, - cmd_ctx->lsm->u.reg.path, cdata); - break; - } - case LTTNG_DATA_PENDING: - { - int pending_ret; - uint8_t pending_ret_byte; - - pending_ret = cmd_data_pending(cmd_ctx->session); - - /* - * FIXME - * - * This function may returns 0 or 1 to indicate whether or not - * there is data pending. In case of error, it should return an - * LTTNG_ERR code. However, some code paths may still return - * a nondescript error code, which we handle by returning an - * "unknown" error. - */ - if (pending_ret == 0 || pending_ret == 1) { - /* - * ret will be set to LTTNG_OK at the end of - * this function. - */ - } else if (pending_ret < 0) { - ret = LTTNG_ERR_UNK; - goto setup_error; - } else { - ret = pending_ret; - goto setup_error; - } - - pending_ret_byte = (uint8_t) pending_ret; - - /* 1 byte to return whether or not data is pending */ - ret = setup_lttng_msg_no_cmd_header(cmd_ctx, - &pending_ret_byte, 1); - - if (ret < 0) { - goto setup_error; - } - - ret = LTTNG_OK; - break; - } - case LTTNG_SNAPSHOT_ADD_OUTPUT: - { - struct lttcomm_lttng_output_id reply; - - ret = cmd_snapshot_add_output(cmd_ctx->session, - &cmd_ctx->lsm->u.snapshot_output.output, &reply.id); - if (ret != LTTNG_OK) { - goto error; - } - - ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &reply, - sizeof(reply)); - if (ret < 0) { - goto setup_error; - } - - /* Copy output list into message payload */ - ret = LTTNG_OK; - break; - } - case LTTNG_SNAPSHOT_DEL_OUTPUT: - { - ret = cmd_snapshot_del_output(cmd_ctx->session, - &cmd_ctx->lsm->u.snapshot_output.output); - break; - } - case LTTNG_SNAPSHOT_LIST_OUTPUT: - { - ssize_t nb_output; - struct lttng_snapshot_output *outputs = NULL; - - nb_output = cmd_snapshot_list_outputs(cmd_ctx->session, &outputs); - if (nb_output < 0) { - ret = -nb_output; - goto error; - } - - assert((nb_output > 0 && outputs) || nb_output == 0); - ret = setup_lttng_msg_no_cmd_header(cmd_ctx, outputs, - nb_output * sizeof(struct lttng_snapshot_output)); - free(outputs); - - if (ret < 0) { - goto setup_error; - } - - ret = LTTNG_OK; - break; - } - case LTTNG_SNAPSHOT_RECORD: - { - ret = cmd_snapshot_record(cmd_ctx->session, - &cmd_ctx->lsm->u.snapshot_record.output, - cmd_ctx->lsm->u.snapshot_record.wait); - break; - } - case LTTNG_CREATE_SESSION_SNAPSHOT: - { - size_t nb_uri, len; - struct lttng_uri *uris = NULL; - - nb_uri = cmd_ctx->lsm->u.uri.size; - len = nb_uri * sizeof(struct lttng_uri); - - if (nb_uri > 0) { - uris = zmalloc(len); - if (uris == NULL) { - ret = LTTNG_ERR_FATAL; - goto error; - } - - /* Receive variable len data */ - DBG("Waiting for %zu URIs from client ...", nb_uri); - ret = lttcomm_recv_unix_sock(sock, uris, len); - if (ret <= 0) { - DBG("No URIs received from client... continuing"); - *sock_error = 1; - ret = LTTNG_ERR_SESSION_FAIL; - free(uris); - goto error; - } - - if (nb_uri == 1 && uris[0].dtype != LTTNG_DST_PATH) { - DBG("Creating session with ONE network URI is a bad call"); - ret = LTTNG_ERR_SESSION_FAIL; - free(uris); - goto error; - } - } - - ret = cmd_create_session_snapshot(cmd_ctx->lsm->session.name, uris, - nb_uri, &cmd_ctx->creds); - free(uris); - break; - } - case LTTNG_CREATE_SESSION_LIVE: - { - size_t nb_uri, len; - struct lttng_uri *uris = NULL; - - nb_uri = cmd_ctx->lsm->u.uri.size; - len = nb_uri * sizeof(struct lttng_uri); - - if (nb_uri > 0) { - uris = zmalloc(len); - if (uris == NULL) { - ret = LTTNG_ERR_FATAL; - goto error; - } - - /* Receive variable len data */ - DBG("Waiting for %zu URIs from client ...", nb_uri); - ret = lttcomm_recv_unix_sock(sock, uris, len); - if (ret <= 0) { - DBG("No URIs received from client... continuing"); - *sock_error = 1; - ret = LTTNG_ERR_SESSION_FAIL; - free(uris); - goto error; - } - - if (nb_uri == 1 && uris[0].dtype != LTTNG_DST_PATH) { - DBG("Creating session with ONE network URI is a bad call"); - ret = LTTNG_ERR_SESSION_FAIL; - free(uris); - goto error; - } - } - - ret = cmd_create_session_uri(cmd_ctx->lsm->session.name, uris, - nb_uri, &cmd_ctx->creds, cmd_ctx->lsm->u.session_live.timer_interval); - free(uris); - break; - } - case LTTNG_SAVE_SESSION: - { - ret = cmd_save_sessions(&cmd_ctx->lsm->u.save_session.attr, - &cmd_ctx->creds); - break; - } - case LTTNG_SET_SESSION_SHM_PATH: - { - ret = cmd_set_session_shm_path(cmd_ctx->session, - cmd_ctx->lsm->u.set_shm_path.shm_path); - break; - } - case LTTNG_REGENERATE_METADATA: - { - ret = cmd_regenerate_metadata(cmd_ctx->session); - break; - } - case LTTNG_REGENERATE_STATEDUMP: - { - ret = cmd_regenerate_statedump(cmd_ctx->session); - break; - } - case LTTNG_REGISTER_TRIGGER: - { - ret = cmd_register_trigger(cmd_ctx, sock, - notification_thread_handle); - break; - } - case LTTNG_UNREGISTER_TRIGGER: - { - ret = cmd_unregister_trigger(cmd_ctx, sock, - notification_thread_handle); - break; - } - case LTTNG_ROTATE_SESSION: - { - struct lttng_rotate_session_return rotate_return; - - DBG("Client rotate session \"%s\"", cmd_ctx->session->name); - - memset(&rotate_return, 0, sizeof(rotate_return)); - if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) { - DBG("Kernel tracer version is not compatible with the rotation feature"); - ret = LTTNG_ERR_ROTATION_WRONG_VERSION; - goto error; - } - - ret = cmd_rotate_session(cmd_ctx->session, &rotate_return); - if (ret < 0) { - ret = -ret; - goto error; - } - - ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &rotate_return, - sizeof(rotate_return)); - if (ret < 0) { - ret = -ret; - goto error; - } - - ret = LTTNG_OK; - break; - } - case LTTNG_ROTATION_GET_INFO: - { - struct lttng_rotation_get_info_return get_info_return; - - memset(&get_info_return, 0, sizeof(get_info_return)); - ret = cmd_rotate_get_info(cmd_ctx->session, &get_info_return, - cmd_ctx->lsm->u.get_rotation_info.rotation_id); - if (ret < 0) { - ret = -ret; - goto error; - } - - ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &get_info_return, - sizeof(get_info_return)); - if (ret < 0) { - ret = -ret; - goto error; - } - - ret = LTTNG_OK; - break; - } - case LTTNG_ROTATION_SET_SCHEDULE: - { - bool set_schedule; - enum lttng_rotation_schedule_type schedule_type; - uint64_t value; - - if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) { - DBG("Kernel tracer version does not support session rotations"); - ret = LTTNG_ERR_ROTATION_WRONG_VERSION; - goto error; - } - - set_schedule = cmd_ctx->lsm->u.rotation_set_schedule.set == 1; - schedule_type = (enum lttng_rotation_schedule_type) cmd_ctx->lsm->u.rotation_set_schedule.type; - value = cmd_ctx->lsm->u.rotation_set_schedule.value; - - ret = cmd_rotation_set_schedule(cmd_ctx->session, - set_schedule, - schedule_type, - value, - notification_thread_handle); - if (ret != LTTNG_OK) { - goto error; - } - - break; - } - case LTTNG_SESSION_LIST_ROTATION_SCHEDULES: - { - struct lttng_session_list_schedules_return schedules = { - .periodic.set = !!cmd_ctx->session->rotate_timer_period, - .periodic.value = cmd_ctx->session->rotate_timer_period, - .size.set = !!cmd_ctx->session->rotate_size, - .size.value = cmd_ctx->session->rotate_size, - }; - - ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &schedules, - sizeof(schedules)); - if (ret < 0) { - ret = -ret; - goto error; - } - - ret = LTTNG_OK; - break; - } - default: - ret = LTTNG_ERR_UND; - break; - } - -error: - if (cmd_ctx->llm == NULL) { - DBG("Missing llm structure. Allocating one."); - if (setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0) < 0) { - goto setup_error; - } - } - /* Set return code */ - cmd_ctx->llm->ret_code = ret; -setup_error: - if (cmd_ctx->session) { - session_unlock(cmd_ctx->session); - session_put(cmd_ctx->session); - } - if (need_tracing_session) { - session_unlock_list(); - } -init_setup_error: - assert(!rcu_read_ongoing()); - return ret; -} - -/* - * This thread manage all clients request using the unix client socket for - * communication. - */ -static void *thread_manage_clients(void *data) -{ - int sock = -1, ret, i, pollfd, err = -1; - int sock_error; - uint32_t revents, nb_fd; - struct command_ctx *cmd_ctx = NULL; - struct lttng_poll_event events; - - DBG("[thread] Manage client started"); - - rcu_register_thread(); - - health_register(health_sessiond, HEALTH_SESSIOND_TYPE_CMD); - - health_code_update(); - - ret = lttcomm_listen_unix_sock(client_sock); - if (ret < 0) { - goto error_listen; - } - - /* - * Pass 2 as size here for the thread quit pipe and client_sock. Nothing - * more will be added to this poll set. - */ - ret = sessiond_set_thread_pollset(&events, 2); - if (ret < 0) { - goto error_create_poll; - } - - /* Add the application registration socket */ - ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI); - if (ret < 0) { - goto error; - } - - ret = sem_post(&load_info->message_thread_ready); - if (ret) { - PERROR("sem_post message_thread_ready"); - goto error; - } - - /* - * Wait until all support threads are initialized before accepting - * commands. - */ - while (uatomic_read(<tng_sessiond_ready) != 0) { - /* - * If a support thread failed to launch, it may signal that - * we must exit and the sessiond would never be marked as - * "ready". - * - * The timeout is set to 1ms, which serves as a way to - * pace down this check. - */ - ret = sessiond_wait_for_quit_pipe(1000); - if (ret > 0) { - goto exit; - } - } - /* - * This barrier is paired with the one in sessiond_notify_ready() to - * ensure that loads accessing data initialized by the other threads, - * on which this thread was waiting, are not performed before this point. - * - * Note that this could be a 'read' memory barrier, but a full barrier - * is used in case the code changes. The performance implications of - * this choice are minimal since this is a slow path. - */ - cmm_smp_mb(); - - /* This testpoint is after we signal readiness to the parent. */ - if (testpoint(sessiond_thread_manage_clients)) { - goto error; - } - - if (testpoint(sessiond_thread_manage_clients_before_loop)) { - goto error; - } - - health_code_update(); - - /* Set state as running. */ - sessiond_set_client_thread_state(true); - - while (1) { - const struct cmd_completion_handler *cmd_completion_handler; - - DBG("Accepting client command ..."); - - /* Inifinite blocking call, waiting for transmission */ - restart: - health_poll_entry(); - ret = lttng_poll_wait(&events, -1); - health_poll_exit(); - if (ret < 0) { - /* - * Restart interrupted system call. - */ - if (errno == EINTR) { - goto restart; - } - goto error; - } - - nb_fd = ret; - - for (i = 0; i < nb_fd; i++) { - /* Fetch once the poll data */ - revents = LTTNG_POLL_GETEV(&events, i); - pollfd = LTTNG_POLL_GETFD(&events, i); - - health_code_update(); - - if (!revents) { - /* No activity for this FD (poll implementation). */ - continue; - } - - /* Thread quit pipe has been closed. Killing thread. */ - ret = sessiond_check_thread_quit_pipe(pollfd, revents); - if (ret) { - err = 0; - goto exit; - } - - /* Event on the registration socket */ - if (pollfd == client_sock) { - if (revents & LPOLLIN) { - continue; - } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) { - ERR("Client socket poll error"); - goto error; - } else { - ERR("Unexpected poll events %u for sock %d", revents, pollfd); - goto error; - } - } - } - - DBG("Wait for client response"); - - health_code_update(); - - sock = lttcomm_accept_unix_sock(client_sock); - if (sock < 0) { - goto error; - } - - /* - * Set the CLOEXEC flag. Return code is useless because either way, the - * show must go on. - */ - (void) utils_set_fd_cloexec(sock); - - /* Set socket option for credentials retrieval */ - ret = lttcomm_setsockopt_creds_unix_sock(sock); - if (ret < 0) { - goto error; - } - - /* Allocate context command to process the client request */ - cmd_ctx = zmalloc(sizeof(struct command_ctx)); - if (cmd_ctx == NULL) { - PERROR("zmalloc cmd_ctx"); - goto error; - } - - /* Allocate data buffer for reception */ - cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg)); - if (cmd_ctx->lsm == NULL) { - PERROR("zmalloc cmd_ctx->lsm"); - goto error; - } - - cmd_ctx->llm = NULL; - cmd_ctx->session = NULL; - - health_code_update(); - - /* - * 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_creds_unix_sock(sock, cmd_ctx->lsm, - sizeof(struct lttcomm_session_msg), &cmd_ctx->creds); - if (ret <= 0) { - DBG("Nothing recv() from client... continuing"); - ret = close(sock); - if (ret) { - PERROR("close"); - } - sock = -1; - clean_command_ctx(&cmd_ctx); - continue; - } - - health_code_update(); - - // TODO: Validate cmd_ctx including sanity check for - // security purpose. - - rcu_thread_online(); - /* - * 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, sock, &sock_error); - rcu_thread_offline(); - if (ret < 0) { - ret = close(sock); - if (ret) { - PERROR("close"); - } - sock = -1; - /* - * TODO: Inform client somehow of the fatal error. At - * this point, ret < 0 means that a zmalloc failed - * (ENOMEM). Error detected but still accept - * command, unless a socket error has been - * detected. - */ - clean_command_ctx(&cmd_ctx); - continue; - } - - cmd_completion_handler = cmd_pop_completion_handler(); - if (cmd_completion_handler) { - enum lttng_error_code completion_code; - - completion_code = cmd_completion_handler->run( - cmd_completion_handler->data); - if (completion_code != LTTNG_OK) { - clean_command_ctx(&cmd_ctx); - continue; - } - } - - health_code_update(); - - DBG("Sending response (size: %d, retcode: %s (%d))", - cmd_ctx->lttng_msg_size, - lttng_strerror(-cmd_ctx->llm->ret_code), - 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"); - } - - /* End of transmission */ - ret = close(sock); - if (ret) { - PERROR("close"); - } - sock = -1; - - clean_command_ctx(&cmd_ctx); - - health_code_update(); - } - -exit: -error: - if (sock >= 0) { - ret = close(sock); - if (ret) { - PERROR("close"); - } - } - - lttng_poll_clean(&events); - clean_command_ctx(&cmd_ctx); - -error_listen: -error_create_poll: - unlink(config.client_unix_sock_path.value); - if (client_sock >= 0) { - ret = close(client_sock); - if (ret) { - PERROR("close"); - } - } - - if (err) { - health_error(); - ERR("Health error occurred in %s", __func__); - } - - health_unregister(health_sessiond); - - DBG("Client thread dying"); - - rcu_unregister_thread(); - - /* - * Since we are creating the consumer threads, we own them, so we need - * to join them before our thread exits. - */ - ret = join_consumer_thread(&kconsumer_data); - if (ret) { - errno = ret; - PERROR("join_consumer"); - } - - ret = join_consumer_thread(&ustconsumer32_data); - if (ret) { - errno = ret; - PERROR("join_consumer ust32"); - } - - ret = join_consumer_thread(&ustconsumer64_data); - if (ret) { - errno = ret; - PERROR("join_consumer ust64"); - } - - /* Set state as non-running. */ - sessiond_set_client_thread_state(false); - return NULL; -} - -static int string_match(const char *str1, const char *str2) -{ - return (str1 && str2) && !strcmp(str1, str2); -} - -/* - * Take an option from the getopt output and set it in the right variable to be - * used later. - * - * Return 0 on success else a negative value. - */ -static int set_option(int opt, const char *arg, const char *optname) -{ - int ret = 0; + int ret = 0; if (string_match(optname, "client-sock") || opt == 'c') { if (!arg || *arg == '\0') { @@ -5030,9 +2512,7 @@ end: } /* - * 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). + * Creates the application socket. */ static int init_daemon_socket(void) { @@ -5041,30 +2521,6 @@ static int init_daemon_socket(void) old_umask = umask(0); - /* Create client tool unix socket */ - client_sock = lttcomm_create_unix_sock(config.client_unix_sock_path.value); - if (client_sock < 0) { - ERR("Create unix sock failed: %s", config.client_unix_sock_path.value); - ret = -1; - goto end; - } - - /* Set the cloexec flag */ - ret = utils_set_fd_cloexec(client_sock); - if (ret < 0) { - ERR("Unable to set CLOEXEC flag to the client Unix socket (fd: %d). " - "Continuing but note that the consumer daemon will have a " - "reference to this socket on exec()", client_sock); - } - - /* File permission MUST be 660 */ - ret = chmod(config.client_unix_sock_path.value, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP); - if (ret < 0) { - ERR("Set file permissions failed: %s", config.client_unix_sock_path.value); - PERROR("chmod"); - goto end; - } - /* Create the application unix socket */ apps_sock = lttcomm_create_unix_sock(config.apps_unix_sock_path.value); if (apps_sock < 0) { @@ -5090,8 +2546,8 @@ static int init_daemon_socket(void) goto end; } - DBG3("Session daemon client socket %d and application socket %d created", - client_sock, apps_sock); + DBG3("Session daemon application socket %d created", + apps_sock); end: umask(old_umask); @@ -5448,12 +2904,6 @@ static void destroy_all_sessions_and_wait(void) return; } - /* - * Ensure that the client thread is no longer accepting new commands, - * which could cause new sessions to be created. - */ - sessiond_wait_client_thread_stopped(); - session_lock_list(); /* Initiate the destruction of all sessions. */ cds_list_for_each_entry_safe(session, tmp, @@ -5497,6 +2947,7 @@ int main(int argc, char **argv) struct rotation_thread_handle *rotation_thread_handle = NULL; /* Queue of rotation jobs populated by the sessiond-timer. */ struct rotation_thread_timer_queue *rotation_timer_queue = NULL; + struct lttng_thread *client_thread = NULL; init_kernel_workarounds(); @@ -5887,13 +3338,9 @@ int main(int argc, char **argv) } /* Create thread to manage the client socket */ - ret = pthread_create(&client_thread, default_pthread_attr(), - thread_manage_clients, (void *) NULL); - if (ret) { - errno = ret; - PERROR("pthread_create clients"); + client_thread = launch_client_thread(); + if (!client_thread) { retval = -1; - stop_threads(); goto exit_client; } @@ -5991,6 +3438,17 @@ int main(int argc, char **argv) /* Initiate teardown once activity occurs on the quit pipe. */ sessiond_wait_for_quit_pipe(-1U); + + /* + * Ensure that the client thread is no longer accepting new commands, + * which could cause new sessions to be created. + */ + if (!lttng_thread_shutdown(client_thread)) { + ERR("Failed to shutdown the client thread, continuing teardown"); + lttng_thread_put(client_thread); + client_thread = NULL; + } + destroy_all_sessions_and_wait(); exit_load_session: @@ -6047,20 +3505,16 @@ exit_reg_apps: retval = -1; } exit_dispatch: - - ret = pthread_join(client_thread, &status); - if (ret) { - errno = ret; - PERROR("pthread_join"); - retval = -1; - } - exit_client: exit_rotation: exit_notification: lttng_thread_list_shutdown_orphans(); exit_health: exit_init_data: + if (client_thread) { + lttng_thread_put(client_thread); + } + /* * Wait for all pending call_rcu work to complete before tearing * down data structures. call_rcu worker may be trying to diff --git a/src/bin/lttng-sessiond/thread-utils.c b/src/bin/lttng-sessiond/thread-utils.c index 3a8ddb330..549cd69f8 100644 --- a/src/bin/lttng-sessiond/thread-utils.c +++ b/src/bin/lttng-sessiond/thread-utils.c @@ -30,19 +30,6 @@ */ static int thread_quit_pipe[2] = { -1, -1 }; -/* - * Allows threads to query the state of the client thread. - */ -static struct client_thread_state { - pthread_cond_t cond; - pthread_mutex_t lock; - bool is_running; -} client_thread_state = { - .cond = PTHREAD_COND_INITIALIZER, - .lock = PTHREAD_MUTEX_INITIALIZER, - .is_running = false -}; - /* * Init thread quit pipe. * @@ -136,24 +123,6 @@ void sessiond_close_quit_pipe(void) utils_close_pipe(thread_quit_pipe); } -void sessiond_set_client_thread_state(bool running) -{ - pthread_mutex_lock(&client_thread_state.lock); - client_thread_state.is_running = running; - pthread_cond_broadcast(&client_thread_state.cond); - pthread_mutex_unlock(&client_thread_state.lock); -} - -void sessiond_wait_client_thread_stopped(void) -{ - pthread_mutex_lock(&client_thread_state.lock); - while (client_thread_state.is_running) { - pthread_cond_wait(&client_thread_state.cond, - &client_thread_state.lock); - } - pthread_mutex_unlock(&client_thread_state.lock); -} - static int __sessiond_set_thread_pollset(struct lttng_poll_event *events, size_t size, int *a_pipe)