[lwip-users] Core locking with NO_SYS

[Christoph M. Wintersteiger]

I’m getting some mixed signals about core locking and I wonder whether someone could clarify this. The documentation for LWIP_ASSERT_CORE_LOCKED (https://www.nongnu.org/lwip/2_1_x/group__lwip__opts__lock.html#ga6a30040db307b3459fc11906bd433f75 ) says:

 

Not in ISR (this should be checked for NO_SYS==1, too!)

 

From this I infer that core locking with NO_SYS==1 is possible and indeed a good idea.

 

However, when I enable core locking (#define LWIP_TCPIP_CORE_LOCKING 1), the LOCK_TCPIP_CORE macro is undefined. I figured I’ll just lock it myself via sys_mutex_lock(&lock_tcpip_core), but it appears that sys_mutex_lock is defined to do nothing at all (sys.h, #if NO_SYS).

 

So, has support for core locking + NO_SYS been removed, and the documentation is lagging behind, or is there a different way to enable this?

 

(Context: I’m using MQTT and it appears that it has a hard requirement for core locking…)

 

Thanks,

Christoph