/*
* Return value read from /proc or else 0 if value is not found.
*/
static unsigned long read_proc_value(const char *path)
{
int ret, fd;
ssize_t size_ret;
long r_val;
unsigned long val = 0;
char buf[64];
fd = open(path, O_RDONLY);
if (fd < 0) {
goto error;
}
size_ret = lttng_read(fd, buf, sizeof(buf));
/*
* Allow reading a file smaller than buf, but keep space for
* final \0.
*/
if (size_ret < 0 || size_ret >= sizeof(buf)) {
PERROR("read proc failed");
goto error_close;
}
buf[size_ret] = '\0';
errno = 0;
r_val = strtol(buf, NULL, 10);
if (errno != 0 || r_val < -1L) {
val = 0;
goto error_close;
} else {
if (r_val > 0) {
val = r_val;
}
}
error_close:
ret = close(fd);
if (ret) {
PERROR("close /proc value");
}
error:
return val;
}
/*
* Read index values from the given index file.
*
* Return 0 on success, -1 on error.
*/
int lttng_index_file_read(const struct lttng_index_file *index_file,
struct ctf_packet_index *element)
{
ssize_t ret;
int fd = index_file->fd;
size_t len = index_file->element_len;
assert(element);
if (fd < 0) {
goto error;
}
ret = lttng_read(fd, element, len);
if (ret < len) {
PERROR("read index file");
goto error;
}
return 0;
error:
return -1;
}
/*
* Setup poll set maximum size.
*/
int compat_epoll_set_max_size(void)
{
int ret, fd, retval = 0;
ssize_t size_ret;
char buf[64];
fd = open(COMPAT_EPOLL_PROC_PATH, O_RDONLY);
if (fd < 0) {
retval = -1;
goto end;
}
size_ret = lttng_read(fd, buf, sizeof(buf));
/*
* Allow reading a file smaller than buf, but keep space for
* final \0.
*/
if (size_ret < 0 || size_ret >= sizeof(buf)) {
PERROR("read set max size");
retval = -1;
goto end_read;
}
buf[size_ret] = '\0';
poll_max_size = atoi(buf);
end_read:
ret = close(fd);
if (ret) {
PERROR("close");
}
end:
if (!poll_max_size) {
poll_max_size = DEFAULT_POLL_SIZE;
}
DBG("epoll set max size is %d", poll_max_size);
return retval;
}
/*
* Open index file using a given path, channel name and tracefile count.
*
* Return allocated struct lttng_index_file, NULL on error.
*/
struct lttng_index_file *lttng_index_file_open(const char *path_name,
const char *channel_name, uint64_t tracefile_count,
uint64_t tracefile_count_current)
{
struct lttng_index_file *index_file;
int ret, read_fd;
ssize_t read_len;
char fullpath[PATH_MAX];
struct ctf_packet_index_file_hdr hdr;
uint32_t major, minor, element_len;
assert(path_name);
assert(channel_name);
index_file = zmalloc(sizeof(*index_file));
if (!index_file) {
PERROR("allocating lttng_index_file");
goto error;
}
if (tracefile_count > 0) {
ret = snprintf(fullpath, sizeof(fullpath), "%s/" DEFAULT_INDEX_DIR "/%s_%"
PRIu64 DEFAULT_INDEX_FILE_SUFFIX, path_name,
channel_name, tracefile_count_current);
} else {
ret = snprintf(fullpath, sizeof(fullpath), "%s/" DEFAULT_INDEX_DIR "/%s"
DEFAULT_INDEX_FILE_SUFFIX, path_name, channel_name);
}
if (ret < 0) {
PERROR("snprintf index path");
goto error;
}
DBG("Index opening file %s in read only", fullpath);
read_fd = open(fullpath, O_RDONLY);
if (read_fd < 0) {
if (errno == ENOENT) {
ret = -ENOENT;
} else {
PERROR("opening index in read-only");
}
goto error;
}
read_len = lttng_read(read_fd, &hdr, sizeof(hdr));
if (read_len < 0) {
PERROR("Reading index header");
goto error_close;
}
if (be32toh(hdr.magic) != CTF_INDEX_MAGIC) {
ERR("Invalid header magic");
goto error_close;
}
major = be32toh(hdr.index_major);
minor = be32toh(hdr.index_minor);
element_len = be32toh(hdr.packet_index_len);
if (major != CTF_INDEX_MAJOR) {
ERR("Invalid header version");
goto error_close;
}
if (element_len > sizeof(struct ctf_packet_index)) {
ERR("Index element length too long");
goto error_close;
}
index_file->fd = read_fd;
index_file->major = major;
index_file->minor = minor;
index_file->element_len = element_len;
urcu_ref_init(&index_file->ref);
return index_file;
error_close:
if (read_fd >= 0) {
int close_ret;
close_ret = close(read_fd);
if (close_ret < 0) {
PERROR("close read fd %d", read_fd);
}
}
ret = -1;
error:
free(index_file);
return NULL;
}
/*
* Open index file using a given path, channel name and tracefile count.
*
* Return read only FD on success or else a negative value.
*/
int index_open(const char *path_name, const char *channel_name,
uint64_t tracefile_count, uint64_t tracefile_count_current)
{
int ret, read_fd;
ssize_t read_len;
char fullpath[PATH_MAX];
struct ctf_packet_index_file_hdr hdr;
assert(path_name);
assert(channel_name);
if (tracefile_count > 0) {
ret = snprintf(fullpath, sizeof(fullpath), "%s/" DEFAULT_INDEX_DIR "/%s_%"
PRIu64 DEFAULT_INDEX_FILE_SUFFIX, path_name,
channel_name, tracefile_count_current);
} else {
ret = snprintf(fullpath, sizeof(fullpath), "%s/" DEFAULT_INDEX_DIR "/%s"
DEFAULT_INDEX_FILE_SUFFIX, path_name, channel_name);
}
if (ret < 0) {
PERROR("snprintf index path");
goto error;
}
DBG("Index opening file %s in read only", fullpath);
read_fd = open(fullpath, O_RDONLY);
if (read_fd < 0) {
if (errno == ENOENT) {
ret = -ENOENT;
} else {
PERROR("opening index in read-only");
}
goto error;
}
read_len = lttng_read(read_fd, &hdr, sizeof(hdr));
if (read_len < 0) {
PERROR("Reading index header");
goto error_close;
}
if (be32toh(hdr.magic) != CTF_INDEX_MAGIC) {
ERR("Invalid header magic");
goto error_close;
}
if (be32toh(hdr.index_major) != CTF_INDEX_MAJOR ||
be32toh(hdr.index_minor) != CTF_INDEX_MINOR) {
ERR("Invalid header version");
goto error_close;
}
return read_fd;
error_close:
if (read_fd >= 0) {
int close_ret;
close_ret = close(read_fd);
if (close_ret < 0) {
PERROR("close read fd %d", read_fd);
}
}
ret = -1;
error:
return ret;
}
void *thread_ht_cleanup(void *data)
{
int ret, i, pollfd, err = -1;
ssize_t size_ret;
uint32_t revents, nb_fd;
struct lttng_poll_event events;
DBG("[ht-thread] startup.");
rcu_register_thread();
rcu_thread_online();
health_register(health_sessiond, HEALTH_SESSIOND_TYPE_HT_CLEANUP);
health_code_update();
ret = sessiond_set_thread_pollset(&events, 2);
if (ret < 0) {
goto error_poll_create;
}
/* Add pipe to the pollset. */
ret = lttng_poll_add(&events, ht_cleanup_pipe[0], LPOLLIN | LPOLLERR);
if (ret < 0) {
goto error;
}
health_code_update();
while (1) {
DBG3("[ht-thread] Polling on %d fds.",
LTTNG_POLL_GETNB(&events));
/* 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++) {
struct lttng_ht *ht;
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. */
ret = sessiond_check_thread_quit_pipe(pollfd, revents);
if (ret) {
err = 0;
goto exit;
}
assert(pollfd == ht_cleanup_pipe[0]);
if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
ERR("ht cleanup pipe error");
goto error;
} else if (!(revents & LPOLLIN)) {
/* No POLLIN and not a catched error, stop the thread. */
ERR("ht cleanup failed. revent: %u", revents);
goto error;
}
/* Get socket from dispatch thread. */
size_ret = lttng_read(ht_cleanup_pipe[0], &ht,
sizeof(ht));
if (size_ret < sizeof(ht)) {
PERROR("ht cleanup notify pipe");
goto error;
}
health_code_update();
/*
* The whole point of this thread is to call
* lttng_ht_destroy from a context that is NOT:
* 1) a read-side RCU lock,
* 2) a call_rcu thread.
*/
lttng_ht_destroy(ht);
health_code_update();
}
}
exit:
error:
lttng_poll_clean(&events);
error_poll_create:
utils_close_pipe(ht_cleanup_pipe);
ht_cleanup_pipe[0] = ht_cleanup_pipe[1] = -1;
DBG("[ust-thread] cleanup complete.");
if (err) {
health_error();
ERR("Health error occurred in %s", __func__);
}
health_unregister(health_sessiond);
rcu_thread_offline();
rcu_unregister_thread();
return NULL;
}
/*
* This thread manage application notify communication.
*/
void *ust_thread_manage_notify(void *data)
{
int i, ret, pollfd, err = -1;
ssize_t size_ret;
uint32_t revents, nb_fd;
struct lttng_poll_event events;
DBG("[ust-thread] Manage application notify command");
rcu_register_thread();
rcu_thread_online();
health_register(health_sessiond,
HEALTH_SESSIOND_TYPE_APP_MANAGE_NOTIFY);
if (testpoint(sessiond_thread_app_manage_notify)) {
goto error_testpoint;
}
health_code_update();
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;
}
health_code_update();
while (1) {
DBG3("[ust-thread] Manage notify polling on %d fds",
LTTNG_POLL_GETNB(&events));
/* 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. */
ret = sessiond_check_thread_quit_pipe(pollfd, revents);
if (ret) {
err = 0;
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;
}
/* Get socket from dispatch thread. */
size_ret = lttng_read(apps_cmd_notify_pipe[0],
&sock, sizeof(sock));
if (size_ret < sizeof(sock)) {
PERROR("read apps notify pipe");
goto error;
}
health_code_update();
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;
}
/* The socket is closed after a grace period here. */
ust_app_notify_sock_unregister(pollfd);
} else if (revents & (LPOLLIN | LPOLLPRI)) {
ret = ust_app_recv_notify(pollfd);
if (ret < 0) {
/*
* If the notification failed either the application is
* dead or an internal error happened. In both cases,
* we can only continue here. If the application is
* dead, an unregistration will follow or else the
* application will notice that we are not responding
* on that socket and will close it.
*/
continue;
}
} else {
ERR("Unknown poll events %u for sock %d", revents, pollfd);
continue;
}
health_code_update();
}
}
}
exit:
error:
lttng_poll_clean(&events);
error_poll_create:
error_testpoint:
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");
if (err) {
health_error();
ERR("Health error occurred in %s", __func__);
}
health_unregister(health_sessiond);
rcu_thread_offline();
rcu_unregister_thread();
return NULL;
}
