/*
* Grab an additional reference to the passed in vnode info.
*
* The caller must already hold a reference to vnode_info, this function must
* only be used to grab an additional reference from code that wants the
* vnode information to outlive the request structure.
*/
struct vnode_info *grab_vnode_info(struct vnode_info *vnode_info)
{
assert(uatomic_read(&vnode_info->refcnt) > 0);
uatomic_inc(&vnode_info->refcnt);
return vnode_info;
}
/*
* Release a reference to the current vnode information.
*
* Must be called from the main thread.
*/
void put_vnode_info(struct vnode_info *vnode_info)
{
if (vnode_info) {
assert(uatomic_read(&vnode_info->refcnt) > 0);
if (uatomic_sub_return(&vnode_info->refcnt, 1) == 0)
free(vnode_info);
}
}
/* The entry was removed from the hashtable. No more readers can get it. Since
all readers using the node for a longer time (outside the rcu critical
section) increased the refcount, we only need to wait for the refcount
to reach zero. */
static void markDead(struct rcu_head *head) {
struct nodeEntry *entry = (struct nodeEntry*) ((uintptr_t)head - offsetof(struct nodeEntry, rcu_head));
uatomic_and(&entry->refcount, ~ALIVE_BIT); // set the alive bit to zero
if(uatomic_read(&entry->refcount) > 0)
return;
node_deleteMembers(&entry->node);
UA_free(entry);
}
/*
* Wake 1 futex.
*/
LTTNG_HIDDEN
void futex_nto1_wake(int32_t *futex)
{
if (caa_unlikely(uatomic_read(futex) == -1)) {
uatomic_set(futex, 0);
futex_async(futex, FUTEX_WAKE, 1, NULL, NULL, 0);
}
DBG("Futex n to 1 wake done");
}
/*
* Wait futex.
*/
LTTNG_HIDDEN
void futex_nto1_wait(int32_t *futex)
{
cmm_smp_mb();
if (uatomic_read(futex) == -1) {
futex_async(futex, FUTEX_WAIT, -1, NULL, NULL, 0);
}
DBG("Futex n to 1 wait done");
}
/*
* Wake 1 futex.
*/
LTTNG_HIDDEN
void futex_nto1_wake(int32_t *futex)
{
if (caa_unlikely(uatomic_read(futex) != -1))
goto end;
uatomic_set(futex, 0);
if (futex_async(futex, FUTEX_WAKE, 1, NULL, NULL, 0) < 0) {
PERROR("futex_async");
abort();
}
end:
DBG("Futex n to 1 wake done");
}
/*
* synchronize_rcu() waiting. Single thread.
*/
static void wait_gp(void)
{
/* Read reader_gp before read futex */
cmm_smp_rmb();
if (uatomic_read(&rcu_gp.futex) != -1)
return;
while (futex_noasync(&rcu_gp.futex, FUTEX_WAIT, -1,
NULL, NULL, 0)) {
switch (errno) {
case EWOULDBLOCK:
/* Value already changed. */
return;
case EINTR:
/* Retry if interrupted by signal. */
break; /* Get out of switch. */
default:
/* Unexpected error. */
urcu_die(errno);
}
}
}
/*
* Wait futex.
*/
LTTNG_HIDDEN
void futex_nto1_wait(int32_t *futex)
{
cmm_smp_mb();
if (uatomic_read(futex) != -1)
goto end;
while (futex_async(futex, FUTEX_WAIT, -1, NULL, NULL, 0)) {
switch (errno) {
case EWOULDBLOCK:
/* Value already changed. */
goto end;
case EINTR:
/* Retry if interrupted by signal. */
break; /* Get out of switch. */
default:
/* Unexpected error. */
PERROR("futex_async");
abort();
}
}
end:
DBG("Futex n to 1 wait done");
}
operator T() const {
return uatomic_read(&m_counter);
}
/*
* main
*/
int main(int argc, char **argv)
{
int ret = 0, retval = 0;
void *status;
if (set_signal_handler()) {
retval = -1;
goto exit_set_signal_handler;
}
/* Parse arguments */
progname = argv[0];
if (parse_args(argc, argv)) {
retval = -1;
goto exit_options;
}
/* Daemonize */
if (opt_daemon) {
int i;
/*
* fork
* child: setsid, close FD 0, 1, 2, chdir /
* parent: exit (if fork is successful)
*/
ret = daemon(0, 0);
if (ret < 0) {
PERROR("daemon");
retval = -1;
goto exit_options;
}
/*
* We are in the child. Make sure all other file
* descriptors are closed, in case we are called with
* more opened file descriptors than the standard ones.
*/
for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) {
(void) close(i);
}
}
/*
* Starting from here, we can create threads. This needs to be after
* lttng_daemonize due to RCU.
*/
health_consumerd = health_app_create(NR_HEALTH_CONSUMERD_TYPES);
if (!health_consumerd) {
retval = -1;
goto exit_health_consumerd_cleanup;
}
/* Set up max poll set size */
if (lttng_poll_set_max_size()) {
retval = -1;
goto exit_init_data;
}
if (*command_sock_path == '\0') {
switch (opt_type) {
case LTTNG_CONSUMER_KERNEL:
ret = snprintf(command_sock_path, PATH_MAX,
DEFAULT_KCONSUMERD_CMD_SOCK_PATH,
DEFAULT_LTTNG_RUNDIR);
if (ret < 0) {
retval = -1;
goto exit_init_data;
}
break;
case LTTNG_CONSUMER64_UST:
ret = snprintf(command_sock_path, PATH_MAX,
DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH,
DEFAULT_LTTNG_RUNDIR);
if (ret < 0) {
retval = -1;
goto exit_init_data;
}
break;
case LTTNG_CONSUMER32_UST:
ret = snprintf(command_sock_path, PATH_MAX,
DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH,
DEFAULT_LTTNG_RUNDIR);
if (ret < 0) {
retval = -1;
goto exit_init_data;
}
break;
default:
ERR("Unknown consumerd type");
retval = -1;
goto exit_init_data;
}
}
/* Init */
if (lttng_consumer_init()) {
retval = -1;
goto exit_init_data;
}
/* Initialize communication library */
lttcomm_init();
/* Initialize TCP timeout values */
lttcomm_inet_init();
if (!getuid()) {
/* Set limit for open files */
set_ulimit();
}
/* create the consumer instance with and assign the callbacks */
ctx = lttng_consumer_create(opt_type, lttng_consumer_read_subbuffer,
NULL, lttng_consumer_on_recv_stream, NULL);
if (!ctx) {
retval = -1;
goto exit_init_data;
}
lttng_consumer_set_command_sock_path(ctx, command_sock_path);
if (*error_sock_path == '\0') {
switch (opt_type) {
case LTTNG_CONSUMER_KERNEL:
ret = snprintf(error_sock_path, PATH_MAX,
DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
DEFAULT_LTTNG_RUNDIR);
if (ret < 0) {
retval = -1;
goto exit_init_data;
}
break;
case LTTNG_CONSUMER64_UST:
ret = snprintf(error_sock_path, PATH_MAX,
DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH,
DEFAULT_LTTNG_RUNDIR);
if (ret < 0) {
retval = -1;
goto exit_init_data;
}
break;
case LTTNG_CONSUMER32_UST:
ret = snprintf(error_sock_path, PATH_MAX,
DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH,
DEFAULT_LTTNG_RUNDIR);
if (ret < 0) {
retval = -1;
goto exit_init_data;
}
break;
default:
ERR("Unknown consumerd type");
retval = -1;
goto exit_init_data;
}
}
/* Connect to the socket created by lttng-sessiond to report errors */
DBG("Connecting to error socket %s", error_sock_path);
ret = lttcomm_connect_unix_sock(error_sock_path);
/*
* Not a fatal error, but all communication with lttng-sessiond will
* fail.
*/
if (ret < 0) {
WARN("Cannot connect to error socket (is lttng-sessiond started?)");
}
lttng_consumer_set_error_sock(ctx, ret);
/*
* Block RT signals used for UST periodical metadata flush and the live
* timer in main, and create a dedicated thread to handle these signals.
*/
if (consumer_signal_init()) {
retval = -1;
goto exit_init_data;
}
ctx->type = opt_type;
if (utils_create_pipe(health_quit_pipe)) {
retval = -1;
goto exit_health_pipe;
}
/* Create thread to manage the client socket */
ret = pthread_create(&health_thread, NULL,
thread_manage_health, (void *) NULL);
if (ret) {
errno = ret;
PERROR("pthread_create health");
retval = -1;
goto exit_health_thread;
}
/*
* Wait for health thread to be initialized before letting the
* sessiond thread reply to the sessiond that we are ready.
*/
while (uatomic_read(<tng_consumer_ready)) {
usleep(100000);
}
cmm_smp_mb(); /* Read ready before following operations */
/* Create thread to manage channels */
ret = pthread_create(&channel_thread, NULL,
consumer_thread_channel_poll,
(void *) ctx);
if (ret) {
errno = ret;
PERROR("pthread_create");
retval = -1;
goto exit_channel_thread;
}
/* Create thread to manage the polling/writing of trace metadata */
ret = pthread_create(&metadata_thread, NULL,
consumer_thread_metadata_poll,
(void *) ctx);
if (ret) {
errno = ret;
PERROR("pthread_create");
retval = -1;
goto exit_metadata_thread;
}
/* Create thread to manage the polling/writing of trace data */
ret = pthread_create(&data_thread, NULL, consumer_thread_data_poll,
(void *) ctx);
if (ret) {
errno = ret;
PERROR("pthread_create");
retval = -1;
goto exit_data_thread;
}
/* Create the thread to manage the receive of fd */
ret = pthread_create(&sessiond_thread, NULL,
consumer_thread_sessiond_poll,
(void *) ctx);
if (ret) {
errno = ret;
PERROR("pthread_create");
retval = -1;
goto exit_sessiond_thread;
}
/*
* Create the thread to manage the UST metadata periodic timer and
* live timer.
*/
ret = pthread_create(&metadata_timer_thread, NULL,
consumer_timer_thread, (void *) ctx);
if (ret) {
errno = ret;
PERROR("pthread_create");
retval = -1;
goto exit_metadata_timer_thread;
}
ret = pthread_detach(metadata_timer_thread);
if (ret) {
errno = ret;
PERROR("pthread_detach");
retval = -1;
goto exit_metadata_timer_detach;
}
/*
* This is where we start awaiting program completion (e.g. through
* signal that asks threads to teardown.
*/
exit_metadata_timer_detach:
exit_metadata_timer_thread:
ret = pthread_join(sessiond_thread, &status);
if (ret) {
errno = ret;
PERROR("pthread_join sessiond_thread");
retval = -1;
}
exit_sessiond_thread:
ret = pthread_join(data_thread, &status);
if (ret) {
errno = ret;
PERROR("pthread_join data_thread");
retval = -1;
}
exit_data_thread:
ret = pthread_join(metadata_thread, &status);
if (ret) {
errno = ret;
PERROR("pthread_join metadata_thread");
retval = -1;
}
exit_metadata_thread:
ret = pthread_join(channel_thread, &status);
if (ret) {
errno = ret;
PERROR("pthread_join channel_thread");
retval = -1;
}
exit_channel_thread:
ret = pthread_join(health_thread, &status);
if (ret) {
errno = ret;
PERROR("pthread_join health_thread");
retval = -1;
}
exit_health_thread:
utils_close_pipe(health_quit_pipe);
exit_health_pipe:
exit_init_data:
lttng_consumer_destroy(ctx);
lttng_consumer_cleanup();
if (health_consumerd) {
health_app_destroy(health_consumerd);
}
exit_health_consumerd_cleanup:
exit_options:
exit_set_signal_handler:
if (!retval) {
exit(EXIT_SUCCESS);
} else {
exit(EXIT_FAILURE);
}
}
