[dpdk-dev] [PATCH] net/mlx5: fix debug variable initialization

[dpdk-dev] [PATCH] net/mlx5: fix debug variable initialization

[Gregory Etelson]

Use `__rte_unused` macro to mask a debug variable instead of `#ifdef`.
This way, if the variable is used in a macro, it does not depend on
how the macro is expanded.

Fixes: 91f0e029ce5f ("net/mlx5: translate flex item pattern into matcher")
Signed-off-by: Gregory Etelson <getelson@nvidia.com>
---
 drivers/net/mlx5/mlx5_flow_flex.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_flow_flex.c b/drivers/net/mlx5/mlx5_flow_flex.c
index bdfa383c45..be0f9821ce 100644
--- a/drivers/net/mlx5/mlx5_flow_flex.c
+++ b/drivers/net/mlx5/mlx5_flow_flex.c
@@ -222,9 +222,7 @@ mlx5_flex_flow_translate_item(struct rte_eth_dev *dev,
 			      const struct rte_flow_item *item,
 			      bool is_inner)
 {
-#ifdef RTE_LIBRTE_MLX5_DEBUG
-	struct mlx5_priv *priv = dev->data->dev_private;
-#endif
+	__rte_unused struct mlx5_priv *priv = dev->data->dev_private;
 	const struct rte_flow_item_flex *spec, *mask;
 	void *misc4_m = MLX5_ADDR_OF(fte_match_param, matcher,
 				     misc_parameters_4);
-- 
2.33.1

Re: [dpdk-dev] [PATCH] net/mlx5: fix debug variable initialization

[Ferruh Yigit]

On 11/4/2021 12:23 PM, Gregory Etelson wrote:
> Use `__rte_unused` macro to mask a debug variable instead of `#ifdef`.
> This way, if the variable is used in a macro, it does not depend on
> how the macro is expanded.
> 
> Fixes: 91f0e029ce5f ("net/mlx5: translate flex item pattern into matcher")
> Signed-off-by: Gregory Etelson <getelson@nvidia.com>
> ---
>   drivers/net/mlx5/mlx5_flow_flex.c | 4 +---
>   1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/net/mlx5/mlx5_flow_flex.c b/drivers/net/mlx5/mlx5_flow_flex.c
> index bdfa383c45..be0f9821ce 100644
> --- a/drivers/net/mlx5/mlx5_flow_flex.c
> +++ b/drivers/net/mlx5/mlx5_flow_flex.c
> @@ -222,9 +222,7 @@ mlx5_flex_flow_translate_item(struct rte_eth_dev *dev,
>   			      const struct rte_flow_item *item,
>   			      bool is_inner)
>   {
> -#ifdef RTE_LIBRTE_MLX5_DEBUG
> -	struct mlx5_priv *priv = dev->data->dev_private;
> -#endif
> +	__rte_unused struct mlx5_priv *priv = dev->data->dev_private;

Marking the variable as unused to silence compiler for some cases,
but it is indeed used, what about something like this (inspired by
sfc code):

  #if defined(RTE_LIBRTE_MLX5_DEBUG) || defined(RTE_ENABLE_ASSERT)
    struct mlx5_priv *priv = dev->data->dev_private;
  #endif

>   	const struct rte_flow_item_flex *spec, *mask;
>   	void *misc4_m = MLX5_ADDR_OF(fte_match_param, matcher,
>   				     misc_parameters_4);
> 

[dpdk-dev] [PATCH v2] net/mlx5: fix debug variable initialization

[Gregory Etelson]

MLX5_ASSERT macro expansion depends on RTE_LIBRTE_MLX5_DEBUG and
RTE_ENABLE_ASSERT.
Existing implementation ignored the RTE_ENABLE_ASSERT dependency
in the mlx5_flex_flow_translate_item() scope.
As the result, the `priv` variable was not defined.

Fixes: 91f0e029ce5f ("net/mlx5: translate flex item pattern into matcher")
Signed-off-by: Gregory Etelson <getelson@nvidia.com>
---
 drivers/net/mlx5/mlx5_flow_flex.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_flow_flex.c b/drivers/net/mlx5/mlx5_flow_flex.c
index bdfa383c45..64867dc9e2 100644
--- a/drivers/net/mlx5/mlx5_flow_flex.c
+++ b/drivers/net/mlx5/mlx5_flow_flex.c
@@ -222,9 +222,6 @@ mlx5_flex_flow_translate_item(struct rte_eth_dev *dev,
 			      const struct rte_flow_item *item,
 			      bool is_inner)
 {
-#ifdef RTE_LIBRTE_MLX5_DEBUG
-	struct mlx5_priv *priv = dev->data->dev_private;
-#endif
 	const struct rte_flow_item_flex *spec, *mask;
 	void *misc4_m = MLX5_ADDR_OF(fte_match_param, matcher,
 				     misc_parameters_4);
@@ -237,7 +234,7 @@ mlx5_flex_flow_translate_item(struct rte_eth_dev *dev,
 	spec = item->spec;
 	mask = item->mask;
 	tp = (struct mlx5_flex_item *)spec->handle;
-	MLX5_ASSERT(mlx5_flex_index(priv, tp) >= 0);
+	MLX5_ASSERT(mlx5_flex_index(dev->data->dev_private, tp) >= 0);
 	for (i = 0; i < tp->mapnum; i++) {
 		struct mlx5_flex_pattern_field *map = tp->map + i;
 		uint32_t id = map->reg_id;
-- 
2.33.1

Re: [dpdk-dev] [PATCH] net/mlx5: fix debug variable initialization

[Gregory Etelson]

Hello Ferruh,

I posted updated patch in https://patchwork.dpdk.org/project/dpdk/patch/20211104132853.31403-1-getelson@nvidia.com/

Regards,
Gregory

> 
> On 11/4/2021 12:23 PM, Gregory Etelson wrote:
> > Use `__rte_unused` macro to mask a debug
> variable instead of `#ifdef`.
> > This way, if the variable is used in a macro, it
> does not depend on
> > how the macro is expanded.
> >
> > Fixes: 91f0e029ce5f ("net/mlx5: translate flex
> item pattern into matcher")
> > Signed-off-by: Gregory Etelson
> <getelson@nvidia.com>
> > ---
> >   drivers/net/mlx5/mlx5_flow_flex.c | 4 +---
> >   1 file changed, 1 insertion(+), 3 deletions(-)
> >
> > diff --git a/drivers/net/mlx5/mlx5_flow_flex.c
> b/drivers/net/mlx5/mlx5_flow_flex.c
> > index bdfa383c45..be0f9821ce 100644
> > --- a/drivers/net/mlx5/mlx5_flow_flex.c
> > +++ b/drivers/net/mlx5/mlx5_flow_flex.c
> > @@ -222,9 +222,7 @@
> mlx5_flex_flow_translate_item(struct
> rte_eth_dev *dev,
> >                             const struct rte_flow_item
> *item,
> >                             bool is_inner)
> >   {
> > -#ifdef RTE_LIBRTE_MLX5_DEBUG
> > -     struct mlx5_priv *priv = dev->data-
> >dev_private;
> > -#endif
> > +     __rte_unused struct mlx5_priv *priv =
> dev->data->dev_private;
> 
> Marking the variable as unused to silence
> compiler for some cases,
> but it is indeed used, what about something like
> this (inspired by
> sfc code):
> 
>   #if defined(RTE_LIBRTE_MLX5_DEBUG) ||
> defined(RTE_ENABLE_ASSERT)
>     struct mlx5_priv *priv = dev->data-
> >dev_private;
>   #endif
> 
> >       const struct rte_flow_item_flex *spec,
> *mask;
> >       void *misc4_m =
> MLX5_ADDR_OF(fte_match_param, matcher,
> >                                    misc_parameters_4);
> >

Re: [dpdk-dev] [PATCH v2] net/mlx5: fix debug variable initialization

[Raslan Darawsheh]

Hi,

> -----Original Message-----
> From: Gregory Etelson <getelson@nvidia.com>
> Sent: Thursday, November 4, 2021 3:29 PM
> To: dev@dpdk.org; Gregory Etelson <getelson@nvidia.com>; Slava Ovsiienko
> <viacheslavo@nvidia.com>
> Cc: ferruh.yigit@intel.com; Raslan Darawsheh <rasland@nvidia.com>; Matan
> Azrad <matan@nvidia.com>
> Subject: [PATCH v2] net/mlx5: fix debug variable initialization
> 
> MLX5_ASSERT macro expansion depends on RTE_LIBRTE_MLX5_DEBUG and
> RTE_ENABLE_ASSERT.
> Existing implementation ignored the RTE_ENABLE_ASSERT dependency in
> the mlx5_flex_flow_translate_item() scope.
> As the result, the `priv` variable was not defined.
> 
> Fixes: 91f0e029ce5f ("net/mlx5: translate flex item pattern into matcher")
> Signed-off-by: Gregory Etelson <getelson@nvidia.com>

Squashed into relevant commit in next-net-mlx,

Kindest regards,
Raslan Darawsheh