k0ekk0ek
commented
2 years ago Hi @colazhu! Nice to see there's community interest in getting Cyclone DDS to run on FreeRTOS targets. The self-pipe trick cannot be used with lwIP. At least, not when I ported Cyclone DDS to the FreeRTOS targets we needed to support. That shouldn't matter too much. If I recall correctly, that only meant the waitset doesn't return directly when another participant is added. There's still the timeout that expires so there's only a slight delay when a new participant is added, which usually occurs only at the start. (@eboasson, not to take too much of your time, but does that statement still hold?) The targets worked fine for me otherwise. There's a good chance your problem lies elsewhere, but it's hard to tell without additional information.
On a side note, I'm currently working on replacing the os_sockWaitset which is really the only operating system specific part left in DDSI. For FreeRTOS specifically that means it becomes easier to use an alternate mechanism. I believe FreeRTOS has it's own, non-socket based, event mechanism that hopefully increases performance and makes the whole thing less relient on lwIP (So FreeRTOS+TCP can be used more easily).
eboasson
colazhu
sgf201
I porting the dds to freertos+lwip+posix on stm32H743
in q_receive.c uint32_t recv_thread (void *vrecv_thread_arg) { .... if ((ctx = os_sockWaitsetWait (waitset)) != NULL) <= this function cannot return and block by "lwip_select" { int idx; ddsi_tran_conn_t conn; while ((idx = os_sockWaitsetNextEvent (ctx, &conn)) >= 0) .... } }
on Linux uint32_t listen_thread (struct ddsi_tran_listener *listener) { ... os_sockWaitsetTrigger (gv->recv_threads[0].arg.u.many.ws); <= after this function will made os_sockWaitsetWait pass through ... }
but I found it do nothing when build with LWIP socket os_sockWaitsetTrigger {
if defined(LWIP_SOCKET)
(void)ws; <= do nothing in this function
else
.....
endif
} }
Need Help! how to resolve this problem?