Re: [lwip-users] Bug in pbuf.c regarding PBUF_POOL

[Timmy Brolin]

Jonathan Larmour wrote:

> Leon Woestenberg wrote:
>
> > > Separately, there's the issue that the !SYS_LIGHTWEIGHT_PROT code is 
> > > broken. Someone interested in that code (Christian?) may want to 
> > > take that up.
> >
> > I think it the raw (core) API level is not broken. Also, the core is
> > intentionally designed to be void of any locking mechanisms.
>
> Go back to the start of this thread: pbuf_pool_free_lock is never 
> changed, and pbuf_pool_free_sem is only used by PBUF_POOL_FREE and 
> nowhere else. There is therefore no protection between allocs and frees.

Is it the consensus that lwip at the moment is not thread safe with 
!SYS_LIGHTWEIGHT_PROT, but it is thread safe to some degree with 
SYS_LIGHTWEIGHT_PROT?
Looking at the code, the !SYS_LIGHTWEIGHT_PROT parts of pbuf_pool_free 
and alloc seems to be very broken, with some kind of locks which clearly 
does not work.

Can I find some kind of documentation somewhere on which lwip functions 
are thread safe and which are not?

Regards,
Timmy Brolin