Re: [PATCH bpf-next v2 16/20] selftests/bpf: Add flags and new hints to xdp_hw_metadata

[Larysa Zaremba <larysa.zaremba@intel.com>]

On Tue, Jul 04, 2023 at 01:03:37PM +0200, Jesper Dangaard Brouer wrote:
> 
> On 03/07/2023 20.12, Larysa Zaremba wrote:
> > diff --git a/tools/testing/selftests/bpf/xdp_hw_metadata.c b/tools/testing/selftests/bpf/xdp_hw_metadata.c
> > index 613321eb84c1..d234cbcc9103 100644
> > --- a/tools/testing/selftests/bpf/xdp_hw_metadata.c
> > +++ b/tools/testing/selftests/bpf/xdp_hw_metadata.c
> > @@ -19,6 +19,9 @@
> >   #include "xsk.h"
> >   #include <error.h>
> > +#include <linux/kernel.h>
> > +#include <linux/bits.h>
> > +#include <linux/bitfield.h>
> >   #include <linux/errqueue.h>
> >   #include <linux/if_link.h>
> >   #include <linux/net_tstamp.h>
> > @@ -150,21 +153,34 @@ static __u64 gettime(clockid_t clock_id)
> >   	return (__u64) t.tv_sec * NANOSEC_PER_SEC + t.tv_nsec;
> >   }
> > +#define VLAN_PRIO_MASK		GENMASK(15, 13) /* Priority Code Point */
> > +#define VLAN_CFI_MASK		GENMASK(12, 12) /* Canonical Format / Drop Eligible Indicator */
> > +#define VLAN_VID_MASK		GENMASK(11, 0)	/* VLAN Identifier */
> > +static void print_vlan_tag(__u16 tag)
> > +{
> > +	__u16 vlan_id = FIELD_GET(VLAN_VID_MASK, tag);
> > +	__u8 pcp = FIELD_GET(VLAN_PRIO_MASK, tag);
> > +	bool cfi = FIELD_GET(VLAN_CFI_MASK, tag);
> > +
> > +	printf("PCP=%u, CFI=%d, VID=0x%X\n", pcp, cfi, vlan_id);
> > +}
> > +
> 
> Shouldn't we use DEI instead of CFI ?
> 
> This is new code, and CFI have been deprecated (it was only relevant for
> IEEE 802.5 Token Ring LAN).

You are right, should be DEI.

> 
> --Jesper
> 
>