TD_XCHG_CONTEXT
#define TD_XCHG_CONTEXT_MAX_NUM_XCHGS(ti_root) (TD_XCHG_CONTEXT(ti_root)->maxNumXchgs)
#define TD_XCHG_CONTEXT_NO_USED(ti_root) (TD_XCHG_CONTEXT(ti_root)->noUsed)
#define TD_XCHG_CONTEXT_NO_FREED(ti_root) (TD_XCHG_CONTEXT(ti_root)->noFreed)
#define TD_XCHG_CONTEXT_NO_CMD_RCVD(ti_root) (TD_XCHG_CONTEXT(ti_root)->noCmdRcvd)
#define TD_XCHG_CONTEXT_NO_START_IO(ti_root) (TD_XCHG_CONTEXT(ti_root)->noStartIo)
#define TD_XCHG_CONTEXT_NO_SEND_RSP(ti_root) (TD_XCHG_CONTEXT(ti_root)->noSendRsp)
#define TD_XCHG_CONTEXT_NO_IO_COMPLETED(ti_root) (TD_XCHG_CONTEXT(ti_root)->noCompleted)