/*
* Return an allocated lttng hashtable.
*/
LTTNG_HIDDEN
struct lttng_ht *lttng_ht_new(unsigned long size, int type)
{
struct lttng_ht *ht;
/* Test size */
if (!size)
size = DEFAULT_HT_SIZE;
pthread_mutex_lock(&seed_lock);
if (!seed_init) {
lttng_ht_seed = (unsigned long) time(NULL);
seed_init = true;
}
pthread_mutex_unlock(&seed_lock);
ht = zmalloc(sizeof(*ht));
if (ht == NULL) {
PERROR("zmalloc lttng_ht");
goto error;
}
ht->ht = cds_lfht_new(size, min_hash_alloc_size, max_hash_buckets_size,
CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
/*
* There is already an assert in the RCU hashtable code so if the ht is
* NULL here there is a *huge* problem.
*/
assert(ht->ht);
switch (type) {
case LTTNG_HT_TYPE_STRING:
ht->match_fct = match_str;
ht->hash_fct = hash_key_str;
break;
case LTTNG_HT_TYPE_ULONG:
ht->match_fct = match_ulong;
ht->hash_fct = hash_key_ulong;
break;
case LTTNG_HT_TYPE_U64:
ht->match_fct = match_u64;
ht->hash_fct = hash_key_u64;
break;
case LTTNG_HT_TYPE_TWO_U64:
ht->match_fct = match_two_u64;
ht->hash_fct = hash_key_two_u64;
break;
default:
ERR("Unknown lttng hashtable type %d", type);
lttng_ht_destroy(ht);
goto error;
}
DBG3("Created hashtable size %lu at %p of type %d", size, ht->ht, type);
return ht;
error:
return NULL;
}
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;
}
