On Wed, Nov 15, 2017 at 1:22 PM, Simon Goldschmidt <goldsi...@gmx.de> wrote:
> Amena El Homsi wrote: > > What I know is PBUF_ROM doesn't mean the actual ROM (stable for very > long) but it > > means that the data is immutable and it is located in memory which is > not managed > > by the pbuf system. Am I wrong? > > Yes, you are wrong. ROM means stable for very long, not const :-) > Actually I had this understanding from this link http://www.nongnu.org/lwip/2_0_x/group__pbuf.html > and from the Dunkels book " Design and Implementation of the lwIP TCP/IP > Stack". Thanks for your clarifying, but is there a serious problem in using PBUF_ROM as I did? > > ROM really means stable for long. E.g. when sending via tcp_write with the > nocopy flag, > ROM means the data is stable until all retransmissions are done. This can > be up to some > minutes or hours, depending on the connection. TCP has the sent callback > to tell the > application when it is done, but ARP does not have this. > > As such, when queueing for ARP, we can prevent copying, but you'd never > know when the > frame has actually been sent. > > In this respect, I would be OK with the chang in ARP output, but that > won't help you much > as your usage of PBUF_ROM seems wrong. > > > so I have to add some instructions inside the LwIP code, right? > > You can always change lwIP code, but in my opinion, it's always better to > work together > to get things "mainlined". We'd have to change the queue handling in > etharp_query() > to change this. > > Regarding your original problem: why don't you put (some of) the memp > pools into the > frame memory? > I don't think this will be easy because we have our own memory manager system and the frame memory will be used by the HW MAC and SW MAC, however pools are managed by PBUF manager. It seems that I am facing a serious problem now, your suggestions are really appreciated.. > > Simon > > _______________________________________________ > lwip-users mailing list > lwip-users@nongnu.org > https://lists.nongnu.org/mailman/listinfo/lwip-users > -- Amena El-Homsi Computer & Communication Engineer Dipl. Eng, M.S.
_______________________________________________ lwip-users mailing list lwip-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/lwip-users
