Launch the application management thread with lttng_thread
[lttng-tools.git] / src / bin / lttng-sessiond / main.c
index 4749f8621b62d1b0512304dcbac6677fd1e79124..f1c2cd37cfedf22281f100fc80537259bd3fc32b 100644 (file)
@@ -50,7 +50,6 @@
 #include <common/daemonize.h>
 #include <common/config/session-config.h>
 #include <common/dynamic-buffer.h>
-#include <lttng/userspace-probe-internal.h>
 #include <lttng/event-internal.h>
 
 #include "lttng-sessiond.h"
 #include "sessiond-config.h"
 #include "timer.h"
 #include "thread.h"
+#include "client.h"
+#include "dispatch.h"
+#include "register.h"
+#include "manage-apps.h"
 
 static const char *help_msg =
 #ifdef LTTNG_EMBED_HELP
@@ -98,44 +101,6 @@ 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' },
@@ -172,13 +137,6 @@ static const struct option long_options[] = {
 /* Command line options to ignore from configuration file */
 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;
-
 /*
  * This pipe is used to inform the thread managing application communication
  * that a command is queued and ready to be processed.
@@ -186,16 +144,10 @@ static int apps_sock = -1;
 static int apps_cmd_pipe[2] = { -1, -1 };
 
 /* Pthread, Mutexes and Semaphores */
-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;
 static pthread_t load_session_thread;
-static pthread_t rotation_thread;
-static pthread_t timer_thread;
 
 /*
  * UST registration command queue. This queue is tied with a futex and uses a N
@@ -210,40 +162,6 @@ 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;
 
@@ -255,9 +173,6 @@ static const char * const config_section_name = "sessiond";
 /* Am I root or not. Set to 1 if the daemon is running as root */
 static int is_root;
 
-/* Rotation thread handle. */
-static struct rotation_thread_handle *rotation_thread_handle;
-
 /*
  * Stop all threads by closing the thread quit pipe.
  */
@@ -271,10 +186,6 @@ static void stop_threads(void)
        if (ret < 0) {
                ERR("write error on thread quit pipe");
        }
-
-       /* Dispatch thread */
-       CMM_STORE_SHARED(dispatch_thread_exit, 1);
-       futex_nto1_wake(&ust_cmd_queue.futex);
 }
 
 /*
@@ -388,6 +299,8 @@ static void sessiond_cleanup(void)
                PERROR("remove pidfile %s", config.pid_file_path.value);
        }
 
+       utils_close_pipe(apps_cmd_pipe);
+
        DBG("Removing sessiond and consumerd content of directory %s",
                config.rundir.value);
 
@@ -471,120 +384,6 @@ 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.
- */
-static int notify_ust_apps(int active)
-{
-       char *wait_shm_mmap;
-
-       DBG("Notifying applications of session daemon state: %d", active);
-
-       /* See shm.c for this call implying mmap, shm and futex calls */
-       wait_shm_mmap = shm_ust_get_mmap(config.wait_shm_path.value, is_root);
-       if (wait_shm_mmap == NULL) {
-               goto error;
-       }
-
-       /* Wake waiting process */
-       futex_wait_update((int32_t *) wait_shm_mmap, active);
-
-       /* Apps notified successfully */
-       return 0;
-
-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.
@@ -716,55 +515,6 @@ error:
        return ret;
 }
 
-/*
- * For each tracing session, update newly registered apps. The session list
- * lock MUST be acquired before calling this.
- */
-static void update_ust_app(int app_sock)
-{
-       struct ltt_session *sess, *stmp;
-       const struct ltt_session_list *session_list = session_get_list();
-
-       /* Consumer is in an ERROR state. Stop any application update. */
-       if (uatomic_read(&ust_consumerd_state) == CONSUMER_ERROR) {
-               /* Stop the update process since the consumer is dead. */
-               return;
-       }
-
-       /* For all tracing session(s) */
-       cds_list_for_each_entry_safe(sess, stmp, &session_list->head, list) {
-               struct ust_app *app;
-
-               if (!session_get(sess)) {
-                       continue;
-               }
-               session_lock(sess);
-               if (!sess->ust_session) {
-                       goto unlock_session;
-               }
-
-               rcu_read_lock();
-               assert(app_sock >= 0);
-               app = ust_app_find_by_sock(app_sock);
-               if (app == NULL) {
-                       /*
-                        * Application can be unregistered before so
-                        * this is possible hence simply stopping the
-                        * update.
-                        */
-                       DBG3("UST app update failed to find app sock %d",
-                               app_sock);
-                       goto unlock_rcu;
-               }
-               ust_app_global_update(sess->ust_session, app);
-       unlock_rcu:
-               rcu_read_unlock();
-       unlock_session:
-               session_unlock(sess);
-               session_put(sess);
-       }
-}
-
 /*
  * This thread manage event coming from the kernel.
  *
@@ -944,7 +694,7 @@ 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;
@@ -1232,3238 +982,41 @@ error:
         * We lock here because we are about to close the sockets and some other
         * thread might be using them so get exclusive access which will abort all
         * other consumer command by other threads.
-        */
-       pthread_mutex_lock(&consumer_data->lock);
-
-       /* Immediately set the consumerd state to stopped */
-       if (consumer_data->type == LTTNG_CONSUMER_KERNEL) {
-               uatomic_set(&kernel_consumerd_state, CONSUMER_ERROR);
-       } else if (consumer_data->type == LTTNG_CONSUMER64_UST ||
-                       consumer_data->type == LTTNG_CONSUMER32_UST) {
-               uatomic_set(&ust_consumerd_state, CONSUMER_ERROR);
-       } else {
-               /* Code flow error... */
-               assert(0);
-       }
-
-       if (consumer_data->err_sock >= 0) {
-               ret = close(consumer_data->err_sock);
-               if (ret) {
-                       PERROR("close");
-               }
-               consumer_data->err_sock = -1;
-       }
-       if (consumer_data->cmd_sock >= 0) {
-               ret = close(consumer_data->cmd_sock);
-               if (ret) {
-                       PERROR("close");
-               }
-               consumer_data->cmd_sock = -1;
-       }
-       if (consumer_data->metadata_sock.fd_ptr &&
-           *consumer_data->metadata_sock.fd_ptr >= 0) {
-               ret = close(*consumer_data->metadata_sock.fd_ptr);
-               if (ret) {
-                       PERROR("close");
-               }
-       }
-       if (sock >= 0) {
-               ret = close(sock);
-               if (ret) {
-                       PERROR("close");
-               }
-       }
-
-       unlink(consumer_data->err_unix_sock_path);
-       unlink(consumer_data->cmd_unix_sock_path);
-       pthread_mutex_unlock(&consumer_data->lock);
-
-       /* Cleanup metadata socket mutex. */
-       if (consumer_data->metadata_sock.lock) {
-               pthread_mutex_destroy(consumer_data->metadata_sock.lock);
-               free(consumer_data->metadata_sock.lock);
-       }
-       lttng_poll_clean(&events);
-
-       if (cmd_socket_wrapper) {
-               consumer_destroy_socket(cmd_socket_wrapper);
-       }
-error_poll:
-       if (err) {
-               health_error();
-               ERR("Health error occurred in %s", __func__);
-       }
-       health_unregister(health_sessiond);
-       DBG("consumer thread cleanup completed");
-
-       rcu_thread_offline();
-       rcu_unregister_thread();
-
-       return NULL;
-}
-
-/*
- * This thread receives application command sockets (FDs) on the
- * apps_cmd_pipe and waits (polls) on them until they are closed
- * or an error occurs.
- *
- * At that point, it flushes the data (tracing and metadata) associated
- * with this application and tears down ust app sessions and other
- * associated data structures through ust_app_unregister().
- *
- * Note that this thread never sends commands to the applications
- * through the command sockets; it merely listens for hang-ups
- * and errors on those sockets and cleans-up as they occur.
- */
-static void *thread_manage_apps(void *data)
-{
-       int i, ret, pollfd, err = -1;
-       ssize_t size_ret;
-       uint32_t revents, nb_fd;
-       struct lttng_poll_event events;
-
-       DBG("[thread] Manage application started");
-
-       rcu_register_thread();
-       rcu_thread_online();
-
-       health_register(health_sessiond, HEALTH_SESSIOND_TYPE_APP_MANAGE);
-
-       if (testpoint(sessiond_thread_manage_apps)) {
-               goto error_testpoint;
-       }
-
-       health_code_update();
-
-       ret = sessiond_set_thread_pollset(&events, 2);
-       if (ret < 0) {
-               goto error_poll_create;
-       }
-
-       ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
-       if (ret < 0) {
-               goto error;
-       }
-
-       if (testpoint(sessiond_thread_manage_apps_before_loop)) {
-               goto error;
-       }
-
-       health_code_update();
-
-       while (1) {
-               DBG("Apps thread polling");
-
-               /* Inifinite blocking call, waiting for transmission */
-       restart:
-               health_poll_entry();
-               ret = lttng_poll_wait(&events, -1);
-               DBG("Apps thread return from poll on %d fds",
-                               LTTNG_POLL_GETNB(&events));
-               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;
-                       }
-
-                       /* Inspect the apps cmd pipe */
-                       if (pollfd == apps_cmd_pipe[0]) {
-                               if (revents & LPOLLIN) {
-                                       int sock;
-
-                                       /* Empty pipe */
-                                       size_ret = lttng_read(apps_cmd_pipe[0], &sock, sizeof(sock));
-                                       if (size_ret < sizeof(sock)) {
-                                               PERROR("read apps cmd pipe");
-                                               goto error;
-                                       }
-
-                                       health_code_update();
-
-                                       /*
-                                        * Since this is a command socket (write then read),
-                                        * we only monitor the error events of the socket.
-                                        */
-                                       ret = lttng_poll_add(&events, sock,
-                                                       LPOLLERR | LPOLLHUP | LPOLLRDHUP);
-                                       if (ret < 0) {
-                                               goto error;
-                                       }
-
-                                       DBG("Apps with sock %d added to poll set", sock);
-                               } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
-                                       ERR("Apps command pipe error");
-                                       goto error;
-                               } else {
-                                       ERR("Unknown poll events %u for sock %d", revents, pollfd);
-                                       goto error;
-                               }
-                       } else {
-                               /*
-                                * At this point, we know that a registered application made
-                                * the event at poll_wait.
-                                */
-                               if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
-                                       /* Removing from the poll set */
-                                       ret = lttng_poll_del(&events, pollfd);
-                                       if (ret < 0) {
-                                               goto error;
-                                       }
-
-                                       /* Socket closed on remote end. */
-                                       ust_app_unregister(pollfd);
-                               } else {
-                                       ERR("Unexpected poll events %u for sock %d", revents, pollfd);
-                                       goto error;
-                               }
-                       }
-
-                       health_code_update();
-               }
-       }
-
-exit:
-error:
-       lttng_poll_clean(&events);
-error_poll_create:
-error_testpoint:
-       utils_close_pipe(apps_cmd_pipe);
-       apps_cmd_pipe[0] = apps_cmd_pipe[1] = -1;
-
-       /*
-        * We don't clean the UST app hash table here since already registered
-        * applications can still be controlled so let them be until the session
-        * daemon dies or the applications stop.
-        */
-
-       if (err) {
-               health_error();
-               ERR("Health error occurred in %s", __func__);
-       }
-       health_unregister(health_sessiond);
-       DBG("Application communication apps thread cleanup complete");
-       rcu_thread_offline();
-       rcu_unregister_thread();
-       return NULL;
-}
-
-/*
- * Send a socket to a thread This is called from the dispatch UST registration
- * thread once all sockets are set for the application.
- *
- * The sock value can be invalid, we don't really care, the thread will handle
- * it and make the necessary cleanup if so.
- *
- * On success, return 0 else a negative value being the errno message of the
- * write().
- */
-static int send_socket_to_thread(int fd, int sock)
-{
-       ssize_t ret;
-
-       /*
-        * It's possible that the FD is set as invalid with -1 concurrently just
-        * before calling this function being a shutdown state of the thread.
-        */
-       if (fd < 0) {
-               ret = -EBADF;
-               goto error;
-       }
-
-       ret = lttng_write(fd, &sock, sizeof(sock));
-       if (ret < sizeof(sock)) {
-               PERROR("write apps pipe %d", fd);
-               if (ret < 0) {
-                       ret = -errno;
-               }
-               goto error;
-       }
-
-       /* All good. Don't send back the write positive ret value. */
-       ret = 0;
-error:
-       return (int) ret;
-}
-
-/*
- * Sanitize the wait queue of the dispatch registration thread meaning removing
- * invalid nodes from it. This is to avoid memory leaks for the case the UST
- * notify socket is never received.
- */
-static void sanitize_wait_queue(struct ust_reg_wait_queue *wait_queue)
-{
-       int ret, nb_fd = 0, i;
-       unsigned int fd_added = 0;
-       struct lttng_poll_event events;
-       struct ust_reg_wait_node *wait_node = NULL, *tmp_wait_node;
-
-       assert(wait_queue);
-
-       lttng_poll_init(&events);
-
-       /* Just skip everything for an empty queue. */
-       if (!wait_queue->count) {
-               goto end;
-       }
-
-       ret = lttng_poll_create(&events, wait_queue->count, LTTNG_CLOEXEC);
-       if (ret < 0) {
-               goto error_create;
-       }
-
-       cds_list_for_each_entry_safe(wait_node, tmp_wait_node,
-                       &wait_queue->head, head) {
-               assert(wait_node->app);
-               ret = lttng_poll_add(&events, wait_node->app->sock,
-                               LPOLLHUP | LPOLLERR);
-               if (ret < 0) {
-                       goto error;
-               }
-
-               fd_added = 1;
-       }
-
-       if (!fd_added) {
-               goto end;
-       }
-
-       /*
-        * Poll but don't block so we can quickly identify the faulty events and
-        * clean them afterwards from the wait queue.
-        */
-       ret = lttng_poll_wait(&events, 0);
-       if (ret < 0) {
-               goto error;
-       }
-       nb_fd = ret;
-
-       for (i = 0; i < nb_fd; i++) {
-               /* Get faulty FD. */
-               uint32_t revents = LTTNG_POLL_GETEV(&events, i);
-               int pollfd = LTTNG_POLL_GETFD(&events, i);
-
-               if (!revents) {
-                       /* No activity for this FD (poll implementation). */
-                       continue;
-               }
-
-               cds_list_for_each_entry_safe(wait_node, tmp_wait_node,
-                               &wait_queue->head, head) {
-                       if (pollfd == wait_node->app->sock &&
-                                       (revents & (LPOLLHUP | LPOLLERR))) {
-                               cds_list_del(&wait_node->head);
-                               wait_queue->count--;
-                               ust_app_destroy(wait_node->app);
-                               free(wait_node);
-                               /*
-                                * Silence warning of use-after-free in
-                                * cds_list_for_each_entry_safe which uses
-                                * __typeof__(*wait_node).
-                                */
-                               wait_node = NULL;
-                               break;
-                       } else {
-                               ERR("Unexpected poll events %u for sock %d", revents, pollfd);
-                               goto error;
-                       }
-               }
-       }
-
-       if (nb_fd > 0) {
-               DBG("Wait queue sanitized, %d node were cleaned up", nb_fd);
-       }
-
-end:
-       lttng_poll_clean(&events);
-       return;
-
-error:
-       lttng_poll_clean(&events);
-error_create:
-       ERR("Unable to sanitize wait queue");
-       return;
-}
-
-/*
- * Dispatch request from the registration threads to the application
- * communication thread.
- */
-static void *thread_dispatch_ust_registration(void *data)
-{
-       int ret, err = -1;
-       struct cds_wfcq_node *node;
-       struct ust_command *ust_cmd = NULL;
-       struct ust_reg_wait_node *wait_node = NULL, *tmp_wait_node;
-       struct ust_reg_wait_queue wait_queue = {
-               .count = 0,
-       };
-
-       rcu_register_thread();
-
-       health_register(health_sessiond, HEALTH_SESSIOND_TYPE_APP_REG_DISPATCH);
-
-       if (testpoint(sessiond_thread_app_reg_dispatch)) {
-               goto error_testpoint;
-       }
-
-       health_code_update();
-
-       CDS_INIT_LIST_HEAD(&wait_queue.head);
-
-       DBG("[thread] Dispatch UST command started");
-
-       for (;;) {
-               health_code_update();
-
-               /* Atomically prepare the queue futex */
-               futex_nto1_prepare(&ust_cmd_queue.futex);
-
-               if (CMM_LOAD_SHARED(dispatch_thread_exit)) {
-                       break;
-               }
-
-               do {
-                       struct ust_app *app = NULL;
-                       ust_cmd = NULL;
-
-                       /*
-                        * Make sure we don't have node(s) that have hung up before receiving
-                        * the notify socket. This is to clean the list in order to avoid
-                        * memory leaks from notify socket that are never seen.
-                        */
-                       sanitize_wait_queue(&wait_queue);
-
-                       health_code_update();
-                       /* Dequeue command for registration */
-                       node = cds_wfcq_dequeue_blocking(&ust_cmd_queue.head, &ust_cmd_queue.tail);
-                       if (node == NULL) {
-                               DBG("Woken up but nothing in the UST command queue");
-                               /* Continue thread execution */
-                               break;
-                       }
-
-                       ust_cmd = caa_container_of(node, struct ust_command, node);
-
-                       DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
-                                       " gid:%d sock:%d name:%s (version %d.%d)",
-                                       ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
-                                       ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
-                                       ust_cmd->sock, ust_cmd->reg_msg.name,
-                                       ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
-
-                       if (ust_cmd->reg_msg.type == USTCTL_SOCKET_CMD) {
-                               wait_node = zmalloc(sizeof(*wait_node));
-                               if (!wait_node) {
-                                       PERROR("zmalloc wait_node dispatch");
-                                       ret = close(ust_cmd->sock);
-                                       if (ret < 0) {
-                                               PERROR("close ust sock dispatch %d", ust_cmd->sock);
-                                       }
-                                       lttng_fd_put(LTTNG_FD_APPS, 1);
-                                       free(ust_cmd);
-                                       goto error;
-                               }
-                               CDS_INIT_LIST_HEAD(&wait_node->head);
-
-                               /* Create application object if socket is CMD. */
-                               wait_node->app = ust_app_create(&ust_cmd->reg_msg,
-                                               ust_cmd->sock);
-                               if (!wait_node->app) {
-                                       ret = close(ust_cmd->sock);
-                                       if (ret < 0) {
-                                               PERROR("close ust sock dispatch %d", ust_cmd->sock);
-                                       }
-                                       lttng_fd_put(LTTNG_FD_APPS, 1);
-                                       free(wait_node);
-                                       free(ust_cmd);
-                                       continue;
-                               }
-                               /*
-                                * Add application to the wait queue so we can set the notify
-                                * socket before putting this object in the global ht.
-                                */
-                               cds_list_add(&wait_node->head, &wait_queue.head);
-                               wait_queue.count++;
-
-                               free(ust_cmd);
-                               /*
-                                * We have to continue here since we don't have the notify
-                                * socket and the application MUST be added to the hash table
-                                * only at that moment.
-                                */
-                               continue;
-                       } else {
-                               /*
-                                * Look for the application in the local wait queue and set the
-                                * notify socket if found.
-                                */
-                               cds_list_for_each_entry_safe(wait_node, tmp_wait_node,
-                                               &wait_queue.head, head) {
-                                       health_code_update();
-                                       if (wait_node->app->pid == ust_cmd->reg_msg.pid) {
-                                               wait_node->app->notify_sock = ust_cmd->sock;
-                                               cds_list_del(&wait_node->head);
-                                               wait_queue.count--;
-                                               app = wait_node->app;
-                                               free(wait_node);
-                                               DBG3("UST app notify socket %d is set", ust_cmd->sock);
-                                               break;
-                                       }
-                               }
-
-                               /*
-                                * With no application at this stage the received socket is
-                                * basically useless so close it before we free the cmd data
-                                * structure for good.
-                                */
-                               if (!app) {
-                                       ret = close(ust_cmd->sock);
-                                       if (ret < 0) {
-                                               PERROR("close ust sock dispatch %d", ust_cmd->sock);
-                                       }
-                                       lttng_fd_put(LTTNG_FD_APPS, 1);
-                               }
-                               free(ust_cmd);
-                       }
-
-                       if (app) {
-                               /*
-                                * @session_lock_list
-                                *
-                                * Lock the global session list so from the register up to the
-                                * registration done message, no thread can see the application
-                                * and change its state.
-                                */
-                               session_lock_list();
-                               rcu_read_lock();
-
-                               /*
-                                * Add application to the global hash table. This needs to be
-                                * done before the update to the UST registry can locate the
-                                * application.
-                                */
-                               ust_app_add(app);
-
-                               /* Set app version. This call will print an error if needed. */
-                               (void) ust_app_version(app);
-
-                               /* Send notify socket through the notify pipe. */
-                               ret = send_socket_to_thread(apps_cmd_notify_pipe[1],
-                                               app->notify_sock);
-                               if (ret < 0) {
-                                       rcu_read_unlock();
-                                       session_unlock_list();
-                                       /*
-                                        * No notify thread, stop the UST tracing. However, this is
-                                        * not an internal error of the this thread thus setting
-                                        * the health error code to a normal exit.
-                                        */
-                                       err = 0;
-                                       goto error;
-                               }
-
-                               /*
-                                * Update newly registered application with the tracing
-                                * registry info already enabled information.
-                                */
-                               update_ust_app(app->sock);
-
-                               /*
-                                * Don't care about return value. Let the manage apps threads
-                                * handle app unregistration upon socket close.
-                                */
-                               (void) ust_app_register_done(app);
-
-                               /*
-                                * Even if the application socket has been closed, send the app
-                                * to the thread and unregistration will take place at that
-                                * place.
-                                */
-                               ret = send_socket_to_thread(apps_cmd_pipe[1], app->sock);
-                               if (ret < 0) {
-                                       rcu_read_unlock();
-                                       session_unlock_list();
-                                       /*
-                                        * No apps. thread, stop the UST tracing. However, this is
-                                        * not an internal error of the this thread thus setting
-                                        * the health error code to a normal exit.
-                                        */
-                                       err = 0;
-                                       goto error;
-                               }
-
-                               rcu_read_unlock();
-                               session_unlock_list();
-                       }
-               } while (node != NULL);
-
-               health_poll_entry();
-               /* Futex wait on queue. Blocking call on futex() */
-               futex_nto1_wait(&ust_cmd_queue.futex);
-               health_poll_exit();
-       }
-       /* Normal exit, no error */
-       err = 0;
-
-error:
-       /* Clean up wait queue. */
-       cds_list_for_each_entry_safe(wait_node, tmp_wait_node,
-                       &wait_queue.head, head) {
-               cds_list_del(&wait_node->head);
-               wait_queue.count--;
-               free(wait_node);
-       }
-
-       /* Empty command queue. */
-       for (;;) {
-               /* Dequeue command for registration */
-               node = cds_wfcq_dequeue_blocking(&ust_cmd_queue.head, &ust_cmd_queue.tail);
-               if (node == NULL) {
-                       break;
-               }
-               ust_cmd = caa_container_of(node, struct ust_command, node);
-               ret = close(ust_cmd->sock);
-               if (ret < 0) {
-                       PERROR("close ust sock exit dispatch %d", ust_cmd->sock);
-               }
-               lttng_fd_put(LTTNG_FD_APPS, 1);
-               free(ust_cmd);
-       }
-
-error_testpoint:
-       DBG("Dispatch thread dying");
-       if (err) {
-               health_error();
-               ERR("Health error occurred in %s", __func__);
-       }
-       health_unregister(health_sessiond);
-       rcu_unregister_thread();
-       return NULL;
-}
-
-/*
- * This thread manage application registration.
- */
-static void *thread_registration_apps(void *data)
-{
-       int sock = -1, i, ret, pollfd, err = -1;
-       uint32_t revents, nb_fd;
-       struct lttng_poll_event events;
-       /*
-        * Get allocated in this thread, enqueued to a global queue, dequeued and
-        * freed in the manage apps thread.
-        */
-       struct ust_command *ust_cmd = NULL;
-
-       DBG("[thread] Manage application registration started");
-
-       health_register(health_sessiond, HEALTH_SESSIOND_TYPE_APP_REG);
-
-       if (testpoint(sessiond_thread_registration_apps)) {
-               goto error_testpoint;
-       }
-
-       ret = lttcomm_listen_unix_sock(apps_sock);
-       if (ret < 0) {
-               goto error_listen;
-       }
-
-       /*
-        * Pass 2 as size here for the thread quit pipe and apps socket. 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, apps_sock, LPOLLIN | LPOLLRDHUP);
-       if (ret < 0) {
-               goto error_poll_add;
-       }
-
-       /* Notify all applications to register */
-       ret = notify_ust_apps(1);
-       if (ret < 0) {
-               ERR("Failed to notify applications or create the wait shared memory.\n"
-                       "Execution continues but there might be problem for already\n"
-                       "running applications that wishes to register.");
-       }
-
-       while (1) {
-               DBG("Accepting application registration");
-
-               /* 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++) {
-                       health_code_update();
-
-                       /* Fetch once the poll data */
-                       revents = LTTNG_POLL_GETEV(&events, i);
-                       pollfd = LTTNG_POLL_GETFD(&events, i);
-
-                       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 == apps_sock) {
-                               if (revents & LPOLLIN) {
-                                       sock = lttcomm_accept_unix_sock(apps_sock);
-                                       if (sock < 0) {
-                                               goto error;
-                                       }
-
-                                       /*
-                                        * Set socket timeout for both receiving and ending.
-                                        * app_socket_timeout is in seconds, whereas
-                                        * lttcomm_setsockopt_rcv_timeout and
-                                        * lttcomm_setsockopt_snd_timeout expect msec as
-                                        * parameter.
-                                        */
-                                       if (config.app_socket_timeout >= 0) {
-                                               (void) lttcomm_setsockopt_rcv_timeout(sock,
-                                                               config.app_socket_timeout * 1000);
-                                               (void) lttcomm_setsockopt_snd_timeout(sock,
-                                                               config.app_socket_timeout * 1000);
-                                       }
-
-                                       /*
-                                        * Set the CLOEXEC flag. Return code is useless because
-                                        * either way, the show must go on.
-                                        */
-                                       (void) utils_set_fd_cloexec(sock);
-
-                                       /* Create UST registration command for enqueuing */
-                                       ust_cmd = zmalloc(sizeof(struct ust_command));
-                                       if (ust_cmd == NULL) {
-                                               PERROR("ust command zmalloc");
-                                               ret = close(sock);
-                                               if (ret) {
-                                                       PERROR("close");
-                                               }
-                                               goto error;
-                                       }
-
-                                       /*
-                                        * Using message-based transmissions to ensure we don't
-                                        * have to deal with partially received messages.
-                                        */
-                                       ret = lttng_fd_get(LTTNG_FD_APPS, 1);
-                                       if (ret < 0) {
-                                               ERR("Exhausted file descriptors allowed for applications.");
-                                               free(ust_cmd);
-                                               ret = close(sock);
-                                               if (ret) {
-                                                       PERROR("close");
-                                               }
-                                               sock = -1;
-                                               continue;
-                                       }
-
-                                       health_code_update();
-                                       ret = ust_app_recv_registration(sock, &ust_cmd->reg_msg);
-                                       if (ret < 0) {
-                                               free(ust_cmd);
-                                               /* Close socket of the application. */
-                                               ret = close(sock);
-                                               if (ret) {
-                                                       PERROR("close");
-                                               }
-                                               lttng_fd_put(LTTNG_FD_APPS, 1);
-                                               sock = -1;
-                                               continue;
-                                       }
-                                       health_code_update();
-
-                                       ust_cmd->sock = sock;
-                                       sock = -1;
-
-                                       DBG("UST registration received with pid:%d ppid:%d uid:%d"
-                                                       " gid:%d sock:%d name:%s (version %d.%d)",
-                                                       ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
-                                                       ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
-                                                       ust_cmd->sock, ust_cmd->reg_msg.name,
-                                                       ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
-
-                                       /*
-                                        * Lock free enqueue the registration request. The red pill
-                                        * has been taken! This apps will be part of the *system*.
-                                        */
-                                       cds_wfcq_enqueue(&ust_cmd_queue.head, &ust_cmd_queue.tail, &ust_cmd->node);
-
-                                       /*
-                                        * Wake the registration queue futex. Implicit memory
-                                        * barrier with the exchange in cds_wfcq_enqueue.
-                                        */
-                                       futex_nto1_wake(&ust_cmd_queue.futex);
-                               } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
-                                       ERR("Register apps socket poll error");
-                                       goto error;
-                               } else {
-                                       ERR("Unexpected poll events %u for sock %d", revents, pollfd);
-                                       goto error;
-                               }
-                       }
-               }
-       }
-
-exit:
-error:
-       /* Notify that the registration thread is gone */
-       notify_ust_apps(0);
-
-       if (apps_sock >= 0) {
-               ret = close(apps_sock);
-               if (ret) {
-                       PERROR("close");
-               }
-       }
-       if (sock >= 0) {
-               ret = close(sock);
-               if (ret) {
-                       PERROR("close");
-               }
-               lttng_fd_put(LTTNG_FD_APPS, 1);
-       }
-       unlink(config.apps_unix_sock_path.value);
-
-error_poll_add:
-       lttng_poll_clean(&events);
-error_listen:
-error_create_poll:
-error_testpoint:
-       DBG("UST Registration thread cleanup complete");
-       if (err) {
-               health_error();
-               ERR("Health error occurred in %s", __func__);
-       }
-       health_unregister(health_sessiond);
-
-       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.
- */
-static int init_kernel_tracer(void)
-{
-       int ret;
-
-       /* Modprobe lttng kernel modules */
-       ret = modprobe_lttng_control();
-       if (ret < 0) {
-               goto error;
-       }
-
-       /* Open debugfs lttng */
-       kernel_tracer_fd = open(module_proc_lttng, O_RDWR);
-       if (kernel_tracer_fd < 0) {
-               DBG("Failed to open %s", module_proc_lttng);
-               goto error_open;
-       }
-
-       /* Validate kernel version */
-       ret = kernel_validate_version(kernel_tracer_fd, &kernel_tracer_version,
-                       &kernel_tracer_abi_version);
-       if (ret < 0) {
-               goto error_version;
-       }
-
-       ret = modprobe_lttng_data();
-       if (ret < 0) {
-               goto error_modules;
-       }
-
-       ret = kernel_supports_ring_buffer_snapshot_sample_positions(
-                       kernel_tracer_fd);
-       if (ret < 0) {
-               goto error_modules;
-       }
-
-       if (ret < 1) {
-               WARN("Kernel tracer does not support buffer monitoring. "
-                       "The monitoring timer of channels in the kernel domain "
-                       "will be set to 0 (disabled).");
-       }
-
-       DBG("Kernel tracer fd %d", kernel_tracer_fd);
-       return 0;
-
-error_version:
-       modprobe_remove_lttng_control();
-       ret = close(kernel_tracer_fd);
-       if (ret) {
-               PERROR("close");
-       }
-       kernel_tracer_fd = -1;
-       return LTTNG_ERR_KERN_VERSION;
-
-error_modules:
-       ret = close(kernel_tracer_fd);
-       if (ret) {
-               PERROR("close");
-       }
-
-error_open:
-       modprobe_remove_lttng_control();
-
-error:
-       WARN("No kernel tracer available");
-       kernel_tracer_fd = -1;
-       if (!is_root) {
-               return LTTNG_ERR_NEED_ROOT_SESSIOND;
-       } else {
-               return LTTNG_ERR_KERN_NA;
-       }
-}
-
-
-/*
- * 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;
-}
-
-/*
- * 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(&lttng_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;
-               }
+        */
+       pthread_mutex_lock(&consumer_data->lock);
 
-               cmd_completion_handler = cmd_pop_completion_handler();
-               if (cmd_completion_handler) {
-                       enum lttng_error_code completion_code;
+       /* Immediately set the consumerd state to stopped */
+       if (consumer_data->type == LTTNG_CONSUMER_KERNEL) {
+               uatomic_set(&kernel_consumerd_state, CONSUMER_ERROR);
+       } else if (consumer_data->type == LTTNG_CONSUMER64_UST ||
+                       consumer_data->type == LTTNG_CONSUMER32_UST) {
+               uatomic_set(&ust_consumerd_state, CONSUMER_ERROR);
+       } else {
+               /* Code flow error... */
+               assert(0);
+       }
 
-                       completion_code = cmd_completion_handler->run(
-                                       cmd_completion_handler->data);
-                       if (completion_code != LTTNG_OK) {
-                               clean_command_ctx(&cmd_ctx);
-                               continue;
-                       }
+       if (consumer_data->err_sock >= 0) {
+               ret = close(consumer_data->err_sock);
+               if (ret) {
+                       PERROR("close");
                }
-
-               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");
+               consumer_data->err_sock = -1;
+       }
+       if (consumer_data->cmd_sock >= 0) {
+               ret = close(consumer_data->cmd_sock);
+               if (ret) {
+                       PERROR("close");
                }
-
-               /* End of transmission */
-               ret = close(sock);
+               consumer_data->cmd_sock = -1;
+       }
+       if (consumer_data->metadata_sock.fd_ptr &&
+           *consumer_data->metadata_sock.fd_ptr >= 0) {
+               ret = close(*consumer_data->metadata_sock.fd_ptr);
                if (ret) {
                        PERROR("close");
                }
-               sock = -1;
-
-               clean_command_ctx(&cmd_ctx);
-
-               health_code_update();
        }
-
-exit:
-error:
        if (sock >= 0) {
                ret = close(sock);
                if (ret) {
@@ -4471,55 +1024,107 @@ error:
                }
        }
 
-       lttng_poll_clean(&events);
-       clean_command_ctx(&cmd_ctx);
+       unlink(consumer_data->err_unix_sock_path);
+       unlink(consumer_data->cmd_unix_sock_path);
+       pthread_mutex_unlock(&consumer_data->lock);
 
-error_listen:
-error_create_poll:
-       unlink(config.client_unix_sock_path.value);
-       if (client_sock >= 0) {
-               ret = close(client_sock);
-               if (ret) {
-                       PERROR("close");
-               }
+       /* Cleanup metadata socket mutex. */
+       if (consumer_data->metadata_sock.lock) {
+               pthread_mutex_destroy(consumer_data->metadata_sock.lock);
+               free(consumer_data->metadata_sock.lock);
        }
+       lttng_poll_clean(&events);
 
+       if (cmd_socket_wrapper) {
+               consumer_destroy_socket(cmd_socket_wrapper);
+       }
+error_poll:
        if (err) {
                health_error();
                ERR("Health error occurred in %s", __func__);
        }
-
        health_unregister(health_sessiond);
+       DBG("consumer thread cleanup completed");
 
-       DBG("Client thread dying");
-
+       rcu_thread_offline();
        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");
+       return NULL;
+}
+
+/*
+ * Setup necessary data for kernel tracer action.
+ */
+static int init_kernel_tracer(void)
+{
+       int ret;
+
+       /* Modprobe lttng kernel modules */
+       ret = modprobe_lttng_control();
+       if (ret < 0) {
+               goto error;
+       }
+
+       /* Open debugfs lttng */
+       kernel_tracer_fd = open(module_proc_lttng, O_RDWR);
+       if (kernel_tracer_fd < 0) {
+               DBG("Failed to open %s", module_proc_lttng);
+               goto error_open;
+       }
+
+       /* Validate kernel version */
+       ret = kernel_validate_version(kernel_tracer_fd, &kernel_tracer_version,
+                       &kernel_tracer_abi_version);
+       if (ret < 0) {
+               goto error_version;
+       }
+
+       ret = modprobe_lttng_data();
+       if (ret < 0) {
+               goto error_modules;
+       }
+
+       ret = kernel_supports_ring_buffer_snapshot_sample_positions(
+                       kernel_tracer_fd);
+       if (ret < 0) {
+               goto error_modules;
        }
 
-       ret = join_consumer_thread(&ustconsumer32_data);
+       if (ret < 1) {
+               WARN("Kernel tracer does not support buffer monitoring. "
+                       "The monitoring timer of channels in the kernel domain "
+                       "will be set to 0 (disabled).");
+       }
+
+       DBG("Kernel tracer fd %d", kernel_tracer_fd);
+       return 0;
+
+error_version:
+       modprobe_remove_lttng_control();
+       ret = close(kernel_tracer_fd);
        if (ret) {
-               errno = ret;
-               PERROR("join_consumer ust32");
+               PERROR("close");
        }
+       kernel_tracer_fd = -1;
+       return LTTNG_ERR_KERN_VERSION;
 
-       ret = join_consumer_thread(&ustconsumer64_data);
+error_modules:
+       ret = close(kernel_tracer_fd);
        if (ret) {
-               errno = ret;
-               PERROR("join_consumer ust64");
+               PERROR("close");
        }
 
-       /* Set state as non-running. */
-       sessiond_set_client_thread_state(false);
-       return NULL;
+error_open:
+       modprobe_remove_lttng_control();
+
+error:
+       WARN("No kernel tracer available");
+       kernel_tracer_fd = -1;
+       if (!is_root) {
+               return LTTNG_ERR_NEED_ROOT_SESSIOND;
+       } else {
+               return LTTNG_ERR_KERN_NA;
+       }
 }
 
 static int string_match(const char *str1, const char *str2)
@@ -5034,75 +1639,6 @@ end:
        return ret;
 }
 
-/*
- * 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).
- */
-static int init_daemon_socket(void)
-{
-       int ret = 0;
-       mode_t old_umask;
-
-       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) {
-               ERR("Create unix sock failed: %s", config.apps_unix_sock_path.value);
-               ret = -1;
-               goto end;
-       }
-
-       /* Set the cloexec flag */
-       ret = utils_set_fd_cloexec(apps_sock);
-       if (ret < 0) {
-               ERR("Unable to set CLOEXEC flag to the app Unix socket (fd: %d). "
-                               "Continuing but note that the consumer daemon will have a "
-                               "reference to this socket on exec()", apps_sock);
-       }
-
-       /* File permission MUST be 666 */
-       ret = chmod(config.apps_unix_sock_path.value,
-                       S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
-       if (ret < 0) {
-               ERR("Set file permissions failed: %s", config.apps_unix_sock_path.value);
-               PERROR("chmod");
-               goto end;
-       }
-
-       DBG3("Session daemon client socket %d and application socket %d created",
-                       client_sock, apps_sock);
-
-end:
-       umask(old_umask);
-       return ret;
-}
-
 /*
  * Create lockfile using the rundir and return its fd.
  */
@@ -5453,12 +1989,6 @@ 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,
@@ -5496,12 +2026,13 @@ int main(int argc, char **argv)
        struct lttng_pipe *ust32_channel_monitor_pipe = NULL,
                        *ust64_channel_monitor_pipe = NULL,
                        *kernel_channel_monitor_pipe = NULL;
-       bool rotation_thread_launched = false;
-       bool timer_thread_launched = false;
        struct lttng_thread *ht_cleanup_thread = NULL;
-       struct timer_thread_parameters timer_thread_ctx;
+       struct timer_thread_parameters timer_thread_parameters;
+       /* Rotation thread handle. */
+       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();
 
@@ -5696,7 +2227,8 @@ int main(int argc, char **argv)
                retval = -1;
                goto exit_init_data;
        }
-       timer_thread_ctx.rotation_thread_job_queue = rotation_timer_queue;
+       timer_thread_parameters.rotation_thread_job_queue =
+                       rotation_timer_queue;
 
        ust64_channel_monitor_pipe = lttng_pipe_open(0);
        if (!ust64_channel_monitor_pipe) {
@@ -5772,12 +2304,6 @@ int main(int argc, char **argv)
                goto exit_init_data;
        }
 
-       /* Setup the needed unix socket */
-       if (init_daemon_socket()) {
-               retval = -1;
-               goto exit_init_data;
-       }
-
        /* Set credentials to socket */
        if (is_root && set_permissions(config.rundir.value)) {
                retval = -1;
@@ -5865,20 +2391,13 @@ int main(int argc, char **argv)
        if (!launch_notification_thread(notification_thread_handle)) {
                retval = -1;
                goto exit_notification;
-
        }
 
        /* Create timer thread. */
-       ret = pthread_create(&timer_thread, default_pthread_attr(),
-                       timer_thread_func, &timer_thread_ctx);
-       if (ret) {
-               errno = ret;
-               PERROR("pthread_create timer");
+       if (!launch_timer_thread(&timer_thread_parameters)) {
                retval = -1;
-               stop_threads();
                goto exit_notification;
        }
-       timer_thread_launched = true;
 
        /* rotation_thread_data acquires the pipes' read side. */
        rotation_thread_handle = rotation_thread_handle_create(
@@ -5892,58 +2411,33 @@ int main(int argc, char **argv)
        }
 
        /* Create rotation thread. */
-       ret = pthread_create(&rotation_thread, default_pthread_attr(),
-                       thread_rotation, rotation_thread_handle);
-       if (ret) {
-               errno = ret;
-               PERROR("pthread_create rotation");
+       if (!launch_rotation_thread(rotation_thread_handle)) {
                retval = -1;
-               stop_threads();
                goto exit_rotation;
        }
-       rotation_thread_launched = true;
 
        /* 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;
        }
 
-       /* Create thread to dispatch registration */
-       ret = pthread_create(&dispatch_thread, default_pthread_attr(),
-                       thread_dispatch_ust_registration, (void *) NULL);
-       if (ret) {
-               errno = ret;
-               PERROR("pthread_create dispatch");
+       if (!launch_ust_dispatch_thread(&ust_cmd_queue, apps_cmd_pipe[1],
+                       apps_cmd_notify_pipe[1])) {
                retval = -1;
-               stop_threads();
                goto exit_dispatch;
        }
 
        /* Create thread to manage application registration. */
-       ret = pthread_create(&reg_apps_thread, default_pthread_attr(),
-                       thread_registration_apps, (void *) NULL);
-       if (ret) {
-               errno = ret;
-               PERROR("pthread_create registration");
+       if (!launch_application_registration_thread(&ust_cmd_queue)) {
                retval = -1;
-               stop_threads();
                goto exit_reg_apps;
        }
 
        /* Create thread to manage application socket */
-       ret = pthread_create(&apps_thread, default_pthread_attr(),
-                       thread_manage_apps, (void *) NULL);
-       if (ret) {
-               errno = ret;
-               PERROR("pthread_create apps");
+       if (!launch_application_management_thread(apps_cmd_pipe[0])) {
                retval = -1;
-               stop_threads();
                goto exit_apps;
        }
 
@@ -6008,6 +2502,17 @@ 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:
 
@@ -6036,48 +2541,19 @@ exit_agent_reg:
                retval = -1;
        }
 exit_apps_notify:
-
-       ret = pthread_join(apps_thread, &status);
-       if (ret) {
-               errno = ret;
-               PERROR("pthread_join apps");
-               retval = -1;
-       }
 exit_apps:
-
-       ret = pthread_join(reg_apps_thread, &status);
-       if (ret) {
-               errno = ret;
-               PERROR("pthread_join");
-               retval = -1;
-       }
 exit_reg_apps:
-
-       /*
-        * Join dispatch thread after joining reg_apps_thread to ensure
-        * we don't leak applications in the queue.
-        */
-       ret = pthread_join(dispatch_thread, &status);
-       if (ret) {
-               errno = ret;
-               PERROR("pthread_join");
-               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
@@ -6098,42 +2574,23 @@ exit_init_data:
         */
        rcu_barrier();
 
-       if (rotation_thread_handle) {
-               if (rotation_thread_launched) {
-                       ret = pthread_join(rotation_thread, &status);
-                       if (ret) {
-                               errno = ret;
-                               PERROR("pthread_join rotation thread");
-                               retval = -1;
-                       }
-               }
-               rotation_thread_handle_destroy(rotation_thread_handle);
-       }
-
-       if (timer_thread_launched) {
-               timer_exit();
-               ret = pthread_join(timer_thread, &status);
-               if (ret) {
-                       errno = ret;
-                       PERROR("pthread_join timer thread");
-                       retval = -1;
-               }
-       }
-
        if (ht_cleanup_thread) {
                lttng_thread_shutdown(ht_cleanup_thread);
                lttng_thread_put(ht_cleanup_thread);
        }
 
+       rcu_thread_offline();
+       rcu_unregister_thread();
+
+       if (rotation_thread_handle) {
+               rotation_thread_handle_destroy(rotation_thread_handle);
+       }
+
        /*
         * After the rotation and timer thread have quit, we can safely destroy
         * the rotation_timer_queue.
         */
        rotation_thread_timer_queue_destroy(rotation_timer_queue);
-
-       rcu_thread_offline();
-       rcu_unregister_thread();
-
        /*
         * The teardown of the notification system is performed after the
         * session daemon's teardown in order to allow it to be notified
This page took 0.112079 seconds and 5 git commands to generate.