Re: [lwip-users] Feeding incoming packets to lwIP

[Jani Monoses]

tcpip_input posts messages to a mbox. that mbox is used by tcpip_thread
so there's no need to worry for critical sections here


> 
> So the real question is this: Is it safe to initiate the call to tcpip_input 
> from an independent thread in a preemptive multi-threaded system? I.e., does 
> tcpip_input use kernel calls to pass the packet on to lwIP (which is running 
> in a different thread)?  Or do I need to worry about critical sections in 
> this scenario?
 
> Note that in addition to tcpip_input, ethernetif_input also calls 
> arp_ip_input, arp_arp_input, pbuf_header, and pbuf_free. Are these routines 
> also thread-safe?

yes calling into ARP is an exception to this separation between input/output 
threads and for now you need to be aware
that the network hardare might be touched simultaneously by two threads the 
input (when sending ARP replies) and the output
this might change in the future though