func (p *podNetnsCache) Get(uid string) Netns {
	// lock current snapshot pod map
	p.mu.RLock()
	defer p.mu.RUnlock()
	if info, f := p.currentPodCache[uid]; f {
		return info.Netns
	}
	return nil
}

// make sure uid is in the cache, even if we don't have a netns
func (p *podNetnsCache) Ensure(uid string) {
	p.mu.Lock()
	defer p.mu.Unlock()
	if _, ok := p.currentPodCache[uid]; !ok {

		}
		defer threadNS.Close()

		// switch to target namespace
		if err = NetnsSet(fdable); err != nil {
			return err
		}
		defer func() {
			err := threadNS.Set() // switch back
			if err == nil {
				// Unlock the current thread only when we successfully switched back
				// to the original namespace; otherwise leave the thread locked which
				// will force the runtime to scrap the current thread, that is maybe