[lwip-users] FreeRTOS + Lwip, transmit gets BLOCKED

[Janicek, Marek]

Hello,

 

I have STM32F407 running FreeRTOS + Lwip (netconn). I have several tasks. Only one Task1 is transmitting continously small packets (85 bytes) every 5 miliseconds on ethernet.

Transmitting is randomly paused for a long time (cca 1-2 sec) then it is resumed.

 

Task1 in function lwip_netconn_do_write() takes the semaphore by sys_arch_sem_wait(LWIP_API_MSG_SEM(msg), 0) and Task1 gets BLOCKED. It remains blocked for cca 1-2 seconds.

When tcpip_thread in function lwip_netconn_do_writemore() gives semaphore by sys_sem_signal(op_completed_sem) then Task1 gets finally READY.

 

Please do you have idea why this is happening for such a long time?

 

Thanks

Marek