qmap_fifo
struct qmap_fifo __arena *fifo; /* queue we're on, NULL if not queued */
static void qmap_fifo_enqueue(struct qmap_fifo __arena *fifo, task_ctx_t *taskc)
static task_ctx_t *qmap_fifo_pop(struct qmap_fifo __arena *fifo)
struct qmap_fifo __arena *fifo = taskc->fifo;
struct qmap_fifo fifos[5];