David S. Miller [off-list ref] wrote:

Ok, here is the best idea I've been able to come up with
so far.

It sounds great!

2) As a result of #1, all the pcount crap goes away.
  The need for two MSS state variables (mss_cache,
  and mss_cache_std) and assosciated complexity is
  eliminated as well.

Does this mean that we'll start counting bytes instead
of packets?

If not then please let me know on how you plan to do the
packet counting.
 

static struct sk_buff *tcp_tso_build(struct sk_buff *head, int mss, int num)
{
       struct sk_buff *skb;
       struct sock *sk;
       int err;

       sk = head->sk;
       skb = alloc_skb(sk->sk_prot->max_header, GFP_ATOMIC);

The other good thing about this is that if we do this for all
packets including non-TSO ones, then the TCP stack doesn't have
to own the TCP/IP headers at all.  Then we can stop worrying
about the TSO/COW mangling.

Cheers,
-- 
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Email: Herbert Xu ~{PmV>HI~} [off-list ref]
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