Re: [dpdk-dev] [RFC] app/testpmd: add generic swap forwarding engine

[Xiaoyu Min <jackmin@mellanox.com>]

On Wed, 20-04-22, 10:26, Kevin Traynor wrote:
> On 15/04/2020 14:48, Xiaoyu Min wrote:
> > This RFC propose a generic `swap` forwarding engine, which could be seen
> > as an extension of existing `macswap` but provide more flexibility.
> > 
> > With this generic `swap` forwarding engine, we can `swap` the source and
> > destination of L2/L3 address as well as the source and destination port
> > of L4 according to the user inputs.
> > 
> > This will be very helpful for developer/tester in some test scenarios.
> > For example, connection tracking functinality in OVS, which needs to
> > swap UDP ports in addition to L2/L3 addresses in order to complete one
> > connection.
> > 
> > Signed-off-by: Xiaoyu Min <jackmin@mellanox.com>
> > ---
> >  app/test-pmd/parameters.c                   |  2 ++
> >  doc/guides/testpmd_app_ug/testpmd_funcs.rst | 15 ++++++++++++++-
> >  2 files changed, 16 insertions(+), 1 deletion(-)
> > 
> > diff --git a/app/test-pmd/parameters.c b/app/test-pmd/parameters.c
> > index 404dba2b20..5c9aecd6cb 100644
> > --- a/app/test-pmd/parameters.c
> > +++ b/app/test-pmd/parameters.c
> > @@ -147,6 +147,8 @@ usage(char* progname)
> >  	       "is default).\n");
> >  	printf("  --forward-mode=N: set forwarding mode (N: %s).\n",
> >  	       list_pkt_forwarding_modes());
> > +	printf("  --forward-mode=swap[:TYPE[,TYPE]]: set forwarding mode to swap "
> > +	       "(TYPE: auto (default) or mac or ip or tp).\n");
> >  	printf("  --rss-ip: set RSS functions to IPv4/IPv6 only .\n");
> >  	printf("  --rss-udp: set RSS functions to IPv4/IPv6 + UDP.\n");
> >  	printf("  --rxq=N: set the number of RX queues per port to N.\n");
> > diff --git a/doc/guides/testpmd_app_ug/testpmd_funcs.rst b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> > index dcee5de455..27f0600493 100644
> > --- a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> > +++ b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> > @@ -298,7 +298,7 @@ set fwd
> >  Set the packet forwarding mode::
> >  
> >     testpmd> set fwd (io|mac|macswap|flowgen| \
> > -                     rxonly|txonly|csum|icmpecho|noisy) (""|retry)
> > +                     rxonly|txonly|csum|icmpecho|noisy|swap) (""|retry)
> >  
> >  ``retry`` can be specified for forwarding engines except ``rx_only``.
> >  
> > @@ -336,6 +336,19 @@ The available information categories are:
> >    Simulate more realistic behavior of a guest machine engaged in receiving
> >    and sending packets performing Virtual Network Function (VNF).
> >  
> > +* ``swap[:TYPE[,TYPE]*]``: Generic swap forwarding mode.
> > + 
> > +  Swap the source and destination address or/and source and destination port of packet according to ``TYPE`` before forwarding them.
> > +  ``TYPE`` could be:
> > +
> > +  - ``auto``: swaps all supported fields (L2 to L4) if available, default.
> 
> It's not an intuitive name and doesn't seem like it's really needed.
> Selecting multiple items below is more explicit IMHO.
Yes, it's not really needed. I'll remove it.

> 
> > + 
> > +  - ``mac``: swaps the source address and destination address of Ethernet, as same as ``macswap``.
> > + 
> > +  - ``ip``: swaps the source address and destination address of IP (v4 and v6).
> > + 
> > +  - ``tp``: swaps the source port and destination port of transport layer (TCP and UDP).
> 
> I think 'port' would be clearer.
Yes, it's more clearer. I'll change it to 'port'.
Thank you.

> 
> > +
> >  Example::
> >  
> >     testpmd> set fwd rxonly
> > 
>