cache_get_wq
queue_delayed_work(cache_get_wq(cache), &cache->gc_work, 0);
struct workqueue_struct *cache_get_wq(struct pcache_cache *cache);
queue_delayed_work(cache_get_wq(cache), &cache->gc_work, PCACHE_CACHE_GC_INTERVAL);
queue_delayed_work(cache_get_wq(cache), &kset->flush_work, 1 * HZ);
queue_delayed_work(cache_get_wq(cache), &kset->flush_work, msecs_to_jiffies(100));
queue_work(cache_get_wq(cache), &cache->clean_work);
queue_delayed_work(cache_get_wq(cache), &cache->writeback_work, delay);
queue_delayed_work(cache_get_wq(cache), &cache->writeback_work, 0);
queue_delayed_work(cache_get_wq(cache), &cache->writeback_work, 0);