Re: [PATCH net-next v1 2/3] net/mlx5e: Add helper for encap_info_equal for tunnels with options

[Gavin Li]

On 2/14/2023 11:01 PM, Alexander Lobakin wrote:
> External email: Use caution opening links or attachments
>
>
> From: Gavin Li <gavinl@xxxxxxxxxx>
> Date: Tue, 14 Feb 2023 15:41:36 +0200
>
> (dropping non-existent nikolay@xxxxxxxxxx)
>
> > For tunnels with options, eg, geneve and vxlan with gbp, they share the
> > same way to compare the headers and options. Extract the code as a common
> > function for them
> >
> > Change-Id: I3ea697293c8d5d66c0c20080dbde88f60bcbd62f
> > Signed-off-by: Gavin Li <gavinl@xxxxxxxxxx>
> > Reviewed-by: Roi Dayan <roid@xxxxxxxxxx>
> > Reviewed-by: Maor Dickman <maord@xxxxxxxxxx>
> > Acked-by: Saeed Mahameed <saeedm@xxxxxxxxxx>
> [...]
>
> > diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_encap.c b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_encap.c
> > index 780224fd67a1..4df9d27a63ad 100644
> > --- a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_encap.c
> > +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_encap.c
> > @@ -571,6 +571,35 @@ bool mlx5e_tc_tun_encap_info_equal_generic(struct mlx5e_encap_key *a,
> >                a->tc_tunnel->tunnel_type == b->tc_tunnel->tunnel_type;
> >   }
> >
> > +bool mlx5e_tc_tun_encap_info_equal_options(struct mlx5e_encap_key *a,
> > +                                        struct mlx5e_encap_key *b,
> > +                                        __be16 tun_flags)
> > +{
> > +     struct ip_tunnel_info *a_info;
> > +     struct ip_tunnel_info *b_info;
> > +     bool a_has_opts, b_has_opts;
> > +
> > +     if (!mlx5e_tc_tun_encap_info_equal_generic(a, b))
> > +             return false;
> > +
> > +     a_has_opts = !!(a->ip_tun_key->tun_flags & tun_flags);
> > +     b_has_opts = !!(b->ip_tun_key->tun_flags & tun_flags);
> > +
> > +     /* keys are equal when both don't have any options attached */
> > +     if (!a_has_opts && !b_has_opts)
> > +             return true;
> > +
> > +     if (a_has_opts != b_has_opts)
> > +             return false;
> > +
> > +     /* options stored in memory next to ip_tunnel_info struct */
> > +     a_info = container_of(a->ip_tun_key, struct ip_tunnel_info, key);
> > +     b_info = container_of(b->ip_tun_key, struct ip_tunnel_info, key);
> > +
> > +     return a_info->options_len == b_info->options_len &&
> > +             memcmp(a_info + 1, b_info + 1, a_info->options_len) == 0;
> 1. memcmp() is not aligned to the first expr (off-by-one to the right).
Options start from "info + 1", see ip_tunnel_info_opts and will use it 
here to replace the "info+1".
> 2. `!expr` is preferred over `expr == 0`.
ACK
> > +}
> > +
> >   static int cmp_decap_info(struct mlx5e_decap_key *a,
> >                          struct mlx5e_decap_key *b)
> >   {
> [...]
>
> Thanks,
> Olek