Function rwlock_unwrlock

src/bthread/rwlock.cpp:257–283

}

static inline int rwlock_unwrlock(bthread_rwlock_t* rwlock) {
    rwlock->wlock_flag = false;

    // Announce to readers there is no active writer.
    int reader_count = ((butil::atomic<int>*)&rwlock->reader_count)->fetch_add(
        RWLockMaxReaders, butil::memory_order_release) + RWLockMaxReaders;
    if (BAIDU_UNLIKELY(reader_count >= RWLockMaxReaders)) {
        CHECK(false) << "rwlock_unwlock of unlocked rwlock";
        return EINVAL;
    }

    bool is_valid = bthread::is_contention_site_valid(rwlock->writer_csite);
    if (BAIDU_UNLIKELY(is_valid)) {
        bthread_contention_site_t saved_csite = rwlock->writer_csite;
        bthread::make_contention_site_invalid(&rwlock->writer_csite);

        const int64_t unlock_start_ns = butil::cpuwide_time_ns();
        rwlock_unwrlock_slow(rwlock, reader_count);
        const int64_t unlock_end_ns = butil::cpuwide_time_ns();
        saved_csite.duration_ns += unlock_end_ns - unlock_start_ns;
        bthread::submit_contention(saved_csite, unlock_end_ns);
    } else {
        rwlock_unwrlock_slow(rwlock, reader_count);
    }

    return 0;
}

static inline int rwlock_unlock(bthread_rwlock_t* rwlock) {
    if (rwlock->wlock_flag) {