Re: [PATCH] drm/v3d: Fix compile with CONFIG_WERROR

[Jani Nikula <jani.nikula@linux.intel.com>]

On Mon, 03 Jun 2024, Ashutosh Dixit <ashutosh.dixit@intel.com> wrote:
> Fix compile with CONFIG_WERROR by explicitly computing the max number of
> 7.1 and 4.2 counters.

Nitpick, the warning you're hitting is unused-const-variable. Werror
just turns it into an error.

>
> In file included from ../drivers/gpu/drm/v3d/v3d_drv.h:14,
>                  from ../drivers/gpu/drm/v3d/v3d_bo.c:26:
> ../drivers/gpu/drm/v3d/v3d_performance_counters.h:118:43: \
> 	error: ‘v3d_v42_performance_counters’ defined but not used \
> 	[-Werror=unused-const-variable=]
>
> Fixes: 3cbcbe016c31 ("drm/v3d: Add Performance Counters descriptions for V3D 4.2 and 7.1")
> Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>

This is not the fix that should be done. See [1].

BR,
Jani.


[1] https://lore.kernel.org/r/87msojqv89.fsf@intel.com

> ---
>  drivers/gpu/drm/v3d/v3d_drv.h | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/v3d/v3d_drv.h b/drivers/gpu/drm/v3d/v3d_drv.h
> index 556cbb400ba0..93dccb5f4c23 100644
> --- a/drivers/gpu/drm/v3d/v3d_drv.h
> +++ b/drivers/gpu/drm/v3d/v3d_drv.h
> @@ -352,7 +352,9 @@ struct v3d_timestamp_query {
>  };
>  
>  /* Maximum number of performance counters supported by any version of V3D */
> -#define V3D_MAX_COUNTERS ARRAY_SIZE(v3d_v71_performance_counters)
> +#define MAX(a, b) ((a) > (b) ? (a) : (b))
> +#define V3D_MAX_COUNTERS MAX(ARRAY_SIZE(v3d_v71_performance_counters), \
> +			     ARRAY_SIZE(v3d_v42_performance_counters))
>  
>  /* Number of perfmons required to handle all supported performance counters */
>  #define V3D_MAX_PERFMONS DIV_ROUND_UP(V3D_MAX_COUNTERS, \

-- 
Jani Nikula, Intel