Re: [lwip-devel] Question regarding recent change for bug #3031/task #7896

[Simon Goldschmidt]

Axel Lin wrote:
> I have below changes for my device.
> i.e. a dedicated pbuf pool for tx.
> 
> I add PBUF_POOL_TX in pbuf_type:
> PBUF_POOL = (PBUF_ALLOC_FLAG_RX | PBUF_TYPE_FLAG_STRUCT_DATA_CONTIGUOUS | 
> PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF_POOL),
> PBUF_POOL_TX = (PBUF_TYPE_FLAG_STRUCT_DATA_CONTIGUOUS | 
> PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF_POOL)

Maybe the documentation on the flags isn't clear enough, but this change should 
explicitly help to cleanly solve
situations like yours: Your new pool type should use a new SRC_MASK (i.e. not 
PBUF_TYPE_ALLOC_SRC_MASK_STD_MEMP_PBUF_POOL
but one of 
[PBUF_TYPE_ALLOC_SRC_MASK_APP_MIN..PBUF_TYPE_ALLOC_SRC_MASK_APP_MAX]).

As the documentation says, PBUF_ALLOC_FLAG_RX is used as a marker to implement 
different levels for TX and RX on the same pool!

However, pbuf_free does indeed not yet support freeing such pbufs, I'll have to 
implement that soon.

How do you allocate your new pbuf anyway? Have you changed pbuf_alloc() for 
that?

Simon