Function init_routine

test/bthread_once_unittest.cpp:33–36

butil::atomic<int> g_bthread_once_count(0);

void init_routine() {
    bthread_usleep(2000 * 1000);
    g_bthread_once_count.fetch_add(1, butil::memory_order_relaxed);
}

void bthread_once_task() {
    bthread_once(&g_bthread_once_control, init_routine);