RXRPC_CALL_RX_IS_IDLE
if (test_and_clear_bit(RXRPC_CALL_RX_IS_IDLE, &call->flags))
clear_bit(RXRPC_CALL_RX_IS_IDLE, &call->flags);
!test_and_set_bit(RXRPC_CALL_RX_IS_IDLE, &call->flags))
set_bit(RXRPC_CALL_RX_IS_IDLE, &call->flags);