+++ /dev/null
-/*
- * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
- * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- * 2013 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License, version 2 only,
- * as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
- */
-
-#include "manage-apps.h"
-#include "testpoint.h"
-#include "health-sessiond.h"
-#include "utils.h"
-#include "thread.h"
-
-struct thread_notifiers {
- struct lttng_pipe *quit_pipe;
- int apps_cmd_pipe_read_fd;
-};
-
-static void cleanup_application_management_thread(void *data)
-{
- struct thread_notifiers *notifiers = data;
-
- lttng_pipe_destroy(notifiers->quit_pipe);
- free(notifiers);
-}
-
-/*
- * 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_application_management(void *data)
-{
- int i, ret, pollfd, err = -1;
- ssize_t size_ret;
- uint32_t revents, nb_fd;
- struct lttng_poll_event events;
- struct thread_notifiers *notifiers = data;
- const int quit_pipe_read_fd = lttng_pipe_get_readfd(
- notifiers->quit_pipe);
-
- 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 = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
- if (ret < 0) {
- goto error_poll_create;
- }
-
- ret = lttng_poll_add(&events, notifiers->apps_cmd_pipe_read_fd,
- LPOLLIN | LPOLLRDHUP);
- if (ret < 0) {
- goto error;
- }
-
- ret = lttng_poll_add(&events, quit_pipe_read_fd, LPOLLIN | LPOLLERR);
- 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;
- }
-
- if (pollfd == quit_pipe_read_fd) {
- err = 0;
- goto exit;
- } else if (pollfd == notifiers->apps_cmd_pipe_read_fd) {
- /* Inspect the apps cmd pipe */
- if (revents & LPOLLIN) {
- int sock;
-
- /* Empty pipe */
- size_ret = lttng_read(
- notifiers->apps_cmd_pipe_read_fd,
- &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:
-
- /*
- * 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;
-}
-
-static bool shutdown_application_management_thread(void *data)
-{
- struct thread_notifiers *notifiers = data;
- const int write_fd = lttng_pipe_get_writefd(notifiers->quit_pipe);
-
- return notify_thread_pipe(write_fd) == 1;
-}
-
-bool launch_application_management_thread(int apps_cmd_pipe_read_fd)
-{
- struct lttng_pipe *quit_pipe;
- struct thread_notifiers *notifiers = NULL;
- struct lttng_thread *thread;
-
- quit_pipe = lttng_pipe_open(FD_CLOEXEC);
- if (!quit_pipe) {
- goto error;
- }
-
- notifiers = zmalloc(sizeof(*notifiers));
- if (!notifiers) {
- goto error;
- }
- notifiers->quit_pipe = quit_pipe;
- notifiers->apps_cmd_pipe_read_fd = apps_cmd_pipe_read_fd;
-
- thread = lttng_thread_create("UST application management",
- thread_application_management,
- shutdown_application_management_thread,
- cleanup_application_management_thread,
- notifiers);
- if (!thread) {
- goto error;
- }
-
- lttng_thread_put(thread);
- return true;
-error:
- cleanup_application_management_thread(notifiers);
- return false;
-}