--- /dev/null
+/*
+ * Copyright (C) 2013 - David Goulet <dgoulet@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.
+ */
+#define _GNU_SOURCE
+#include <assert.h>
+
+#include <common/common.h>
+#include <common/utils.h>
+
+#include "fd-limit.h"
+#include "lttng-sessiond.h"
+#include "ust-thread.h"
+
+/*
+ * This thread manage application notify communication.
+ */
+void *ust_thread_manage_notify(void *data)
+{
+ int i, ret, pollfd;
+ uint32_t revents, nb_fd;
+ struct lttng_poll_event events;
+
+ DBG("[ust-thread] Manage application notify command");
+
+ rcu_register_thread();
+ rcu_thread_online();
+
+ ret = sessiond_set_thread_pollset(&events, 2);
+ if (ret < 0) {
+ goto error_poll_create;
+ }
+
+ /* Add notify pipe to the pollset. */
+ ret = lttng_poll_add(&events, apps_cmd_notify_pipe[0], LPOLLIN | LPOLLERR);
+ if (ret < 0) {
+ goto error;
+ }
+
+ while (1) {
+ DBG3("[ust-thread] Manage notify polling on %d fds",
+ LTTNG_POLL_GETNB(&events));
+
+ /* Inifinite blocking call, waiting for transmission */
+restart:
+ ret = lttng_poll_wait(&events, -1);
+ 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);
+
+ /* Thread quit pipe has been closed. Killing thread. */
+ ret = sessiond_check_thread_quit_pipe(pollfd, revents);
+ if (ret) {
+ goto exit;
+ }
+
+ /* Inspect the apps cmd pipe */
+ if (pollfd == apps_cmd_notify_pipe[0]) {
+ int sock;
+
+ if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
+ ERR("Apps notify command pipe error");
+ goto error;
+ } else if (!(revents & LPOLLIN)) {
+ /* No POLLIN and not a catched error, stop the thread. */
+ ERR("Notify command pipe failed. revent: %u", revents);
+ goto error;
+ }
+
+ do {
+ /* Get socket from dispatch thread. */
+ ret = read(apps_cmd_notify_pipe[0], &sock, sizeof(sock));
+ } while (ret < 0 && errno == EINTR);
+ if (ret < 0 || ret < sizeof(sock)) {
+ PERROR("read apps notify pipe");
+ goto error;
+ }
+
+ ret = lttng_poll_add(&events, sock,
+ LPOLLIN | LPOLLERR | LPOLLHUP | LPOLLRDHUP);
+ if (ret < 0) {
+ /*
+ * It's possible we've reached the max poll fd allowed.
+ * Let's close the socket but continue normal execution.
+ */
+ ret = close(sock);
+ if (ret) {
+ PERROR("close notify socket %d", sock);
+ }
+ lttng_fd_put(LTTNG_FD_APPS, 1);
+ continue;
+ }
+ DBG3("UST thread notify added sock %d to pollset", sock);
+ } else {
+ /*
+ * At this point, we know that a registered application
+ * triggered the event.
+ */
+ if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
+ /* Removing from the poll set */
+ ret = lttng_poll_del(&events, pollfd);
+ if (ret < 0) {
+ goto error;
+ }
+
+ ret = close(pollfd);
+ if (ret < 0) {
+ PERROR("close sock %d", pollfd);
+ }
+ lttng_fd_put(LTTNG_FD_APPS, 1);
+ } else if (revents & (LPOLLIN | LPOLLPRI)) {
+ ret = ust_app_recv_notify(pollfd);
+ if (ret < 0) {
+ ret = lttng_poll_del(&events, pollfd);
+ if (ret < 0) {
+ goto error;
+ }
+
+ ret = close(pollfd);
+ if (ret < 0) {
+ PERROR("close sock %d", pollfd);
+ }
+ lttng_fd_put(LTTNG_FD_APPS, 1);
+ }
+ } else {
+ ERR("Unknown poll events %u for sock %d", revents, pollfd);
+ continue;
+ }
+ }
+ }
+ }
+
+exit:
+error:
+ lttng_poll_clean(&events);
+error_poll_create:
+ utils_close_pipe(apps_cmd_notify_pipe);
+ apps_cmd_notify_pipe[0] = apps_cmd_notify_pipe[1] = -1;
+ DBG("Application notify communication apps thread cleanup complete");
+ rcu_thread_offline();
+ rcu_unregister_thread();
+ return NULL;
+}
projects / lttng-tools.git / blobdiff