Problems with tcp_retransmit_skb

[Venkatesh Rao]

Hi,
I have a strange problem with tcp_retransmit_skb. I
will describe my setup before i describe my problem.

Setup:
ucLinux 2.4.10 based kernel running on a embedded
processor (coldfire) with 40 MIPS processing
capablity.

Problem:
This embedded system sends relatively huge amount of
data (~1.5MB/s) over ethernet to a remote system which
process the data. On a normal case it all works great.
But when there is a lot of traffic on the network
(simulated by running flood ping between two desktop
linux systems connected to the same hub as this
embedded system), embedded systems Linux TCP/IP stack
go haywire. 

More details:
Since there is a high traffic on the network, the
embedded system cannot transmit packet and this
triggers tcp retransmit in the stack. 

But the first check on the tcp_transmit_skb fails

if (atomic_read(&sk->wmem_alloc) > min_t(int,
sk->wmem_queued+(sk->wmem_queued>>2),sk->sndbuf))

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