+++ /dev/null
-/*
- * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
- * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- * Copyright (C) 2013 Jérémie Galarneau <jeremie.galarneau@efficios.com>
- *
- * SPDX-License-Identifier: GPL-2.0-only
- *
- */
-
-#include <stddef.h>
-#include <stdlib.h>
-#include <urcu.h>
-#include <common/futex.h>
-#include <common/macros.h>
-#include <common/shm.h>
-#include <common/utils.h>
-#include <sys/stat.h>
-
-#include "register.h"
-#include "lttng-sessiond.h"
-#include "testpoint.h"
-#include "health-sessiond.h"
-#include "fd-limit.h"
-#include "utils.h"
-#include "thread.h"
-
-struct thread_state {
- struct lttng_pipe *quit_pipe;
- struct ust_cmd_queue *ust_cmd_queue;
- sem_t ready;
- bool running;
- int application_socket;
-};
-
-/*
- * Creates the application socket.
- */
-static int create_application_socket(void)
-{
- int ret = 0;
- int apps_sock;
- const mode_t old_umask = umask(0);
-
- /* Create the application unix socket */
- apps_sock = lttcomm_create_unix_sock(
- the_config.apps_unix_sock_path.value);
- if (apps_sock < 0) {
- ERR("Create unix sock failed: %s",
- the_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(the_config.apps_unix_sock_path.value,
- S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH |
- S_IWOTH);
- if (ret < 0) {
- PERROR("Set file permissions failed on %s",
- the_config.apps_unix_sock_path.value);
- goto error_close_socket;
- }
-
- DBG3("Session daemon application socket created (fd = %d) ", apps_sock);
- ret = apps_sock;
-end:
- umask(old_umask);
- return ret;
-error_close_socket:
- if (close(apps_sock)) {
- PERROR("Failed to close application socket in error path");
- }
- apps_sock = -1;
- ret = -1;
- goto end;
-}
-
-/*
- * Notify UST applications using the shm mmap futex.
- */
-static int notify_ust_apps(int active, bool is_root)
-{
- 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(
- the_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;
-}
-
-static void cleanup_application_registration_thread(void *data)
-{
- struct thread_state *thread_state = data;
-
- if (!data) {
- return;
- }
-
- lttng_pipe_destroy(thread_state->quit_pipe);
- free(thread_state);
-}
-
-static void set_thread_status(struct thread_state *thread_state, bool running)
-{
- DBG("Marking application registration thread's state as %s", running ? "running" : "error");
- thread_state->running = running;
- sem_post(&thread_state->ready);
-}
-
-static bool wait_thread_status(struct thread_state *thread_state)
-{
- DBG("Waiting for application registration thread to be ready");
- sem_wait(&thread_state->ready);
- if (thread_state->running) {
- DBG("Application registration thread is ready");
- } else {
- ERR("Initialization of application registration thread failed");
- }
-
- return thread_state->running;
-}
-
-static void thread_init_cleanup(void *data)
-{
- struct thread_state *thread_state = data;
-
- set_thread_status(thread_state, false);
-}
-
-/*
- * This thread manage application registration.
- */
-static void *thread_application_registration(void *data)
-{
- int sock = -1, i, ret, pollfd, err = -1;
- uint32_t revents, nb_fd;
- struct lttng_poll_event events;
- /*
- * Gets allocated in this thread, enqueued to a global queue, dequeued
- * and freed in the manage apps thread.
- */
- struct ust_command *ust_cmd = NULL;
- const bool is_root = (getuid() == 0);
- struct thread_state *thread_state = data;
- const int application_socket = thread_state->application_socket;
- const int quit_pipe_read_fd = lttng_pipe_get_readfd(
- thread_state->quit_pipe);
-
- DBG("[thread] Manage application registration started");
-
- pthread_cleanup_push(thread_init_cleanup, thread_state);
- health_register(the_health_sessiond, HEALTH_SESSIOND_TYPE_APP_REG);
-
- ret = lttcomm_listen_unix_sock(application_socket);
- if (ret < 0) {
- goto error_listen;
- }
-
- /*
- * Pass 2 as size here for the thread quit pipe and apps_sock. Nothing
- * more will be added to this poll set.
- */
- ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
- if (ret < 0) {
- goto error_create_poll;
- }
-
- /* Add the application registration socket */
- ret = lttng_poll_add(&events, application_socket, LPOLLIN | LPOLLRDHUP);
- if (ret < 0) {
- goto error_poll_add;
- }
-
- /* Add the application registration socket */
- ret = lttng_poll_add(&events, quit_pipe_read_fd, LPOLLIN | LPOLLRDHUP);
- if (ret < 0) {
- goto error_poll_add;
- }
-
- set_thread_status(thread_state, true);
- pthread_cleanup_pop(0);
-
- if (testpoint(sessiond_thread_registration_apps)) {
- goto error_poll_add;
- }
-
- 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);
-
- /* Thread quit pipe has been closed. Killing thread. */
- if (pollfd == quit_pipe_read_fd) {
- err = 0;
- goto exit;
- } else {
- /* Event on the registration socket */
- if (revents & LPOLLIN) {
- sock = lttcomm_accept_unix_sock(application_socket);
- 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 (the_config.app_socket_timeout >= 0) {
- (void) lttcomm_setsockopt_rcv_timeout(sock,
- the_config.app_socket_timeout * 1000);
- (void) lttcomm_setsockopt_snd_timeout(sock,
- the_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");
- }
- sock = -1;
- 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(&thread_state->ust_cmd_queue->head,
- &thread_state->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(&thread_state->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, is_root);
-
- ret = close(application_socket);
- if (ret) {
- PERROR("Failed to close application registration socket");
- }
- if (sock >= 0) {
- ret = close(sock);
- if (ret) {
- PERROR("Failed to close application socket");
- }
- lttng_fd_put(LTTNG_FD_APPS, 1);
- }
- unlink(the_config.apps_unix_sock_path.value);
-
-error_poll_add:
- lttng_poll_clean(&events);
-error_listen:
-error_create_poll:
- DBG("UST Registration thread cleanup complete");
- if (err) {
- health_error();
- ERR("Health error occurred in %s", __func__);
- }
- health_unregister(the_health_sessiond);
- return NULL;
-}
-
-static bool shutdown_application_registration_thread(void *data)
-{
- struct thread_state *thread_state = data;
- const int write_fd = lttng_pipe_get_writefd(thread_state->quit_pipe);
-
- return notify_thread_pipe(write_fd) == 1;
-}
-
-struct lttng_thread *launch_application_registration_thread(
- struct ust_cmd_queue *cmd_queue)
-{
- int ret;
- struct lttng_pipe *quit_pipe;
- struct thread_state *thread_state = NULL;
- struct lttng_thread *thread = NULL;
- const bool is_root = (getuid() == 0);
- int application_socket = -1;
-
- thread_state = zmalloc(sizeof(*thread_state));
- if (!thread_state) {
- goto error_alloc;
- }
- quit_pipe = lttng_pipe_open(FD_CLOEXEC);
- if (!quit_pipe) {
- goto error;
- }
- thread_state->quit_pipe = quit_pipe;
- thread_state->ust_cmd_queue = cmd_queue;
- application_socket = create_application_socket();
- if (application_socket < 0) {
- goto error;
- }
- thread_state->application_socket = application_socket;
- sem_init(&thread_state->ready, 0, 0);
-
- thread = lttng_thread_create("UST application registration",
- thread_application_registration,
- shutdown_application_registration_thread,
- cleanup_application_registration_thread,
- thread_state);
- if (!thread) {
- goto error;
- }
- /*
- * The application registration thread now owns the application socket
- * and the global thread state. The thread state is used to wait for
- * the thread's status, but its ownership now belongs to the thread.
- */
- application_socket = -1;
- if (!wait_thread_status(thread_state)) {
- thread_state = NULL;
- goto error;
- }
-
- /* Notify all applications to register. */
- ret = notify_ust_apps(1, is_root);
- if (ret < 0) {
- ERR("Failed to notify applications or create the wait shared memory.\n"
- "Execution continues but there might be problems for already\n"
- "running applications that wishes to register.");
- }
-
- return thread;
-error:
- lttng_thread_put(thread);
- cleanup_application_registration_thread(thread_state);
- if (application_socket >= 0) {
- if (close(application_socket)) {
- PERROR("Failed to close application registration socket");
- }
- }
-error_alloc:
- return NULL;
-}
projects / lttng-tools.git / blobdiff