Re: [PATCH v2] net:Add sysctl_tcp_sg_max_skb_frags

[Hans Westgaard Ry]

On 01/27/2016 07:12 PM, Hannes Frederic Sowa wrote:
> On 27.01.2016 16:15, Eric Dumazet wrote:
> > If it is a common one, it should be /proc/sys/net/core/... instead
> > of /proc/sys/net/ipv4/tcp_....
> >
> > Other providers include :
> >
> > 1) GRO stack
> > 2) callers of sock_alloc_send_pskb(), alloc_skb_with_frags(),
> > sock_alloc_send_skb() ..
>
> I agree, this knob should get a generic name and live in a generic 
> net/ directory to control this globally, so things don't break during 
> forwarding etc.
>
> It does not solve the problem completely, e.g. when VMs send gso 
> packets through a vhost-net onto IPoIB, no?
>
> Thanks,
> Hannes
I have understood more of the problem Hannes raises and I realize that 
we need a slowpath in IPoIB to handle the problem
in question. I will make a new version of this patch with a more correct 
position/name of the sysctl-variable.
I'll also make a separate patch adding the slowpath i IPoIB.

Hans