[PATCH] app/testpmd: register metadata dynfield on modify field

[Dariusz Sosnowski]

Hi Ferruh,

> -----Original Message-----
> From: Ferruh Yigit <ferruh.yigit at intel.com>
> Sent: Thursday, March 3, 2022 13:21
> To: Dariusz Sosnowski <dsosnowski at nvidia.com>; Ori Kam
> <orika at nvidia.com>; Xiaoyun Li <xiaoyun.li at intel.com>; Aman Singh
> <aman.deep.singh at intel.com>; Yuying Zhang <yuying.zhang at intel.com>
> Cc: dev at dpdk.org; Slava Ovsiienko <viacheslavo at nvidia.com>
> Subject: Re: [PATCH] app/testpmd: register metadata dynfield on modify
> field
> 
> External email: Use caution opening links or attachments
> 
> 
> On 3/1/2022 11:51 AM, Dariusz Sosnowski wrote:
> > This patch adds implicit registration of metadata dynamic field and
> > flag
> 
> Hi Dariusz,
> 
> metaday dynamic field is explicitly registered when testpmd command used
> to enable tx metadata, or rte flow rule created with "set_meta" action.
> 
> Can you please document more when this implicit enablement is required?
> And why that case doesn't cover above explicit enable cases?

Before this patch, when a user inserted a flow rule with MODIFY_FIELD action,
which modified packet metadata, the metadata dynamic field was not registered, as opposed to
what happened with SET_META action. Goal of this patch is to make the behavior consistent
between these two actions.

Maybe using "implicit" in the commit message was misleading here. 
What do you think about rewording the commit message to something like the one below?

"This patch adds registration of metadata dynamic field and flag
whenever a MODIFY_FIELD action with META as source and/or destination
field is used. It makes the behavior consistent with SET_META action, where
metadata dynamic field and flag is registered on flow rule creation." 

> > whenever a modify_field action with META as source and/or destination
> > field is used.
> >
> 
> According below code it is only registered in the DST_TYPE block, not is 'else'
> (which seems src) leg, is this OK?
> 
> > Signed-off-by: Dariusz Sosnowski <dsosnowski at nvidia.com>
> > Reviewed-by: Viacheslav Ovsiienko <viacheslavo at nvidia.com>
> > ---
> >   app/test-pmd/cmdline_flow.c | 11 +++++++++--
> >   1 file changed, 9 insertions(+), 2 deletions(-)
> >
> > diff --git a/app/test-pmd/cmdline_flow.c b/app/test-pmd/cmdline_flow.c
> > index 4f7a9f17f9..dd38a635b0 100644
> > --- a/app/test-pmd/cmdline_flow.c
> > +++ b/app/test-pmd/cmdline_flow.c
> > @@ -8347,6 +8347,7 @@ parse_vc_modify_field_id(struct context *ctx,
> const struct token *token,
> >   {
> >       struct rte_flow_action_modify_field *action_modify_field;
> >       unsigned int i;
> > +     int ret;
> >
> >       (void)token;
> >       (void)buf;
> > @@ -8362,9 +8363,15 @@ parse_vc_modify_field_id(struct context *ctx,
> const struct token *token,
> >       if (!ctx->object)
> >               return len;
> >       action_modify_field = ctx->object;
> > -     if (ctx->curr == ACTION_MODIFY_FIELD_DST_TYPE_VALUE)
> > +     if (ctx->curr == ACTION_MODIFY_FIELD_DST_TYPE_VALUE) {
> >               action_modify_field->dst.field = (enum rte_flow_field_id)i;
> > -     else
> > +             if (action_modify_field->dst.field == RTE_FLOW_FIELD_META) {
> > +                     ret = rte_flow_dynf_metadata_register();
> > +                     if (ret < 0)
> > +                             return -1;
> > +             }
> > +
> > +     } else
> >               action_modify_field->src.field = (enum rte_flow_field_id)i;
> >       return len;
> >   }

No, I should add registering for source field as well.

Best regards,
Dariusz Sosnowski