dca_dequeue
workp = (dca_work_t *)dca_dequeue(&wlp->dwl_freework);
reqp = (dca_request_t *)dca_dequeue(&wlp->dwl_freereqs);
reqp = (dca_request_t *)dca_dequeue(&wlp->dwl_waitq);
workp = (dca_work_t *)dca_dequeue(&wlp->dwl_runq);
static dca_listnode_t *dca_dequeue(dca_listnode_t *);