Re: [dpdk-dev] [dpdk-stable] [PATCH] net/bnxt: allow configuring vector mode

[Thomas Monjalon <thomas@monjalon.net>]

31/03/2020 17:58, Stephen Hemminger:
> On Tue, 31 Mar 2020 17:43:55 +0200
> Thomas Monjalon <thomas@monjalon.net> wrote:
> > 31/03/2020 16:31, Ajit Khaparde:
> > > On Tue, Mar 31, 2020 at 4:36 AM Ferruh Yigit <ferruh.yigit@intel.com> wrote:
> > > > I saw Ajit merged this patch to brcm tree, but I am not sure about it. We
> > > > have
> > > > already removed this compile time option from some PMDs, and driver tries
> > > > to
> > > > detect to use or not to use vectorization transparently.
> > > >
> > > > This config is also a problem for the meson, which always sets the flag in
> > > > a
> > > > hardcoded way.
> > > >
> > > > But also I am not sure about to need to enable/disable vectorization
> > > > explicitly,
> > > > this patch seems because of this need. As far as I remember in the past
> > > > this
> > > > type of runtime configuration rejected to not make driver configuration
> > > > more
> > > > complex.  
> > > 
> > > Since we need a way to disable or enable vector mode.  
> > 
> > Why do you need to disable vector optimization?
> > Is it for debugging?
> 
> The rte_flow mark operation does not work with the vector optimization.
> 
> The choice to use vector mode is done by the driver earlier in
> the initialization process, and then when application programs rte_flow
> it has a problem; the flow create would fail.

Could we imagine switching the Rx implementation dynamically between 2 bursts?