net/mlx5e: Move priv variable into case statement in mlx5e_setup_tc

There is an unused variable warning on arm64 defconfig when
CONFIG_MLX5_ESWITCH is unset:

drivers/net/ethernet/mellanox/mlx5/core/en_main.c:3467:21: warning:
unused variable 'priv' [-Wunused-variable]
        struct mlx5e_priv *priv = netdev_priv(dev);
                           ^
1 warning generated.

Move it down into the case statement where it is used.

Fixes: 4e95bc268b91 ("net: flow_offload: add flow_block_cb_setup_simple()")
Link: https://github.com/ClangBuiltLinux/linux/issues/597
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

On Wed, Jul 10, 2019 at 12:05 PM Nathan Chancellor
<natechancellor@gmail.com> wrote:
>
> There is an unused variable warning on arm64 defconfig when
> CONFIG_MLX5_ESWITCH is unset:
>
> drivers/net/ethernet/mellanox/mlx5/core/en_main.c:3467:21: warning:
> unused variable 'priv' [-Wunused-variable]
>         struct mlx5e_priv *priv = netdev_priv(dev);
>                            ^
> 1 warning generated.
>
> Move it down into the case statement where it is used.
>
> Fixes: 4e95bc268b91 ("net: flow_offload: add flow_block_cb_setup_simple()")
> Link: https://github.com/ClangBuiltLinux/linux/issues/597
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> ---
>  drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> index 6d0ae87c8ded..651eb714eb5b 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> @@ -3464,15 +3464,16 @@ static LIST_HEAD(mlx5e_block_cb_list);
>  static int mlx5e_setup_tc(struct net_device *dev, enum tc_setup_type type,
>                           void *type_data)
>  {
> -       struct mlx5e_priv *priv = netdev_priv(dev);
> -
>         switch (type) {
>  #ifdef CONFIG_MLX5_ESWITCH
> -       case TC_SETUP_BLOCK:
> +       case TC_SETUP_BLOCK: {
> +               struct mlx5e_priv *priv = netdev_priv(dev);
> +
>                 return flow_block_cb_setup_simple(type_data,
>                                                   &mlx5e_block_cb_list,
>                                                   mlx5e_setup_tc_block_cb,
>                                                   priv, priv, true);
> +       }

Hi Nathan,

We have another patch internally that fixes this, and it is already
queued up in my queue.
it works differently as we want to pass priv instead of netdev to
mlx5e_setup_tc_mqprio below,
which will also solve warning ..

So i would like to submit that patch if it is ok with you ?

>  #endif
>         case TC_SETUP_QDISC_MQPRIO:
>                 return mlx5e_setup_tc_mqprio(dev, type_data);
> --
> 2.22.0
>

On Wed, Jul 10, 2019 at 11:02:00PM -0700, Saeed Mahameed wrote:
> On Wed, Jul 10, 2019 at 12:05 PM Nathan Chancellor
> <natechancellor@gmail.com> wrote:
> >
> > There is an unused variable warning on arm64 defconfig when
> > CONFIG_MLX5_ESWITCH is unset:
> >
> > drivers/net/ethernet/mellanox/mlx5/core/en_main.c:3467:21: warning:
> > unused variable 'priv' [-Wunused-variable]
> >         struct mlx5e_priv *priv = netdev_priv(dev);
> >                            ^
> > 1 warning generated.
> >
> > Move it down into the case statement where it is used.
> >
> > Fixes: 4e95bc268b91 ("net: flow_offload: add flow_block_cb_setup_simple()")
> > Link: https://github.com/ClangBuiltLinux/linux/issues/597
> > Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> > ---
> >  drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 7 ++++---
> >  1 file changed, 4 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> > index 6d0ae87c8ded..651eb714eb5b 100644
> > --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> > +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> > @@ -3464,15 +3464,16 @@ static LIST_HEAD(mlx5e_block_cb_list);
> >  static int mlx5e_setup_tc(struct net_device *dev, enum tc_setup_type type,
> >                           void *type_data)
> >  {
> > -       struct mlx5e_priv *priv = netdev_priv(dev);
> > -
> >         switch (type) {
> >  #ifdef CONFIG_MLX5_ESWITCH
> > -       case TC_SETUP_BLOCK:
> > +       case TC_SETUP_BLOCK: {
> > +               struct mlx5e_priv *priv = netdev_priv(dev);
> > +
> >                 return flow_block_cb_setup_simple(type_data,
> >                                                   &mlx5e_block_cb_list,
> >                                                   mlx5e_setup_tc_block_cb,
> >                                                   priv, priv, true);
> > +       }
> 
> Hi Nathan,
> 
> We have another patch internally that fixes this, and it is already
> queued up in my queue.
> it works differently as we want to pass priv instead of netdev to
> mlx5e_setup_tc_mqprio below,
> which will also solve warning ..
> 
> So i would like to submit that patch if it is ok with you ?

Hi Saeed,

Whatever works best for you, I just care that the warning gets fixed,
not how it is done :) I wouldn't mind being put on CC so I can pick it
up for my local tests.

Thanks for the follow up!
Nathan