[lwip-users] Re: TCP transmission stalls

[铁石]

lwip-users-request,您好！


>Message: 1
>Date: Fri, 16 Jun 2006 15:15:35 +0300
>From: Pavel Grishin <address@hidden>
>Subject: [lwip-users] TCP transmission stalls
>To: Mailing list for lwIP users <address@hidden>
>Message-ID: <address@hidden>
>Content-Type: text/plain; charset=us-ascii
>
>Hello,
>
>I am running a test program which sends some text continuously.
>
>while(1){
>        do{
>                while(tcp_sndbuf(serv_pcb) < strlen(text));
>                err = tcp_write(serv_pcb, text, strlen(text), 0);
>                tcp_output(serv_pcb);
>        }while(err != ERR_OK);
>}
>
>It transmits a number of times and then stops with err = ERR_MEM.
>Why does it happen?
>
>I am using lwIP with VDK and blackfin.
>
>Pavel.
>
   I had ever engage a error some how like your situation. My problem is 
cased by the options in opt.h. The one who port lwip to ucos set the 
PBUF_LINK_HLEN to 14. As the 2byte alinement of the package, and 4byte
alinement of ARM code, lwip would   wipe the mem_free pointer when it write
the link header. So the package pbuf will never be free, after a few 
package sent out ,the memory is use up.
  I set  PBUF_LINK_HLEN to 16 and the problem disappear! Whould this be your 
question too?
(sorry ,my english is poor ,hope that you can understand what I am talking)

= = = = = = = = = = = = = = = = = = = =
                        

　　　　　　　　致
礼！
 
                                 
　　　　　　　　铁石
address@hidden
　　　　　　　　　　2006-06-17