[Mesa-dev] [PATCH] i965: Make intel_get_param return an int

[Ian Romanick]

On 04/11/2016 09:49 AM, Ben Widawsky wrote:
> This will fix the spurious error message: "Failed to query GPU properties."
> that was unintentionally added in cc01b63d730.
> 
> This patch changes the function to return an int so that the caller is able to
> do stuff based on the return value.
> 
> The equivalent of this patch was in the original series that fixed up the
> warning, but I dropped it at the last moment. It is required to make the desired
> behavior of not warning when trying to query GPU properties from the kernel
> unless there is something the user can do about it.
> 
> NOTE: Broadwell appears to actually have some issue where the kernel returns
> ENODEV when it shouldn't be. I will investigate this separately.
> 
> Reported-by: Chris Forbes <chrisf at ijw.co.nz>
> Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
> ---
>  src/mesa/drivers/dri/i965/intel_screen.c | 13 ++++++-------
>  1 file changed, 6 insertions(+), 7 deletions(-)
> 
> diff --git a/src/mesa/drivers/dri/i965/intel_screen.c b/src/mesa/drivers/dri/i965/intel_screen.c
> index 03e6852..d1e8b68 100644
> --- a/src/mesa/drivers/dri/i965/intel_screen.c
> +++ b/src/mesa/drivers/dri/i965/intel_screen.c
> @@ -932,7 +932,7 @@ static const __DRIextension *intelRobustScreenExtensions[] = {
>      NULL
>  };
>  
> -static bool
> +static int
>  intel_get_param(__DRIscreen *psp, int param, int *value)
>  {
>     int ret;
> @@ -946,17 +946,16 @@ intel_get_param(__DRIscreen *psp, int param, int *value)
>     if (ret) {
>        if (ret != -EINVAL)

If you make updates due to other review feedback anyway, I'd be tempted
to combine these as

    if (ret < 0 && ret != -EINVAL)

as in other places, but I don't care too much either way.

>  	 _mesa_warning(NULL, "drm_i915_getparam: %d", ret);
> -      return false;
>     }
>  
> -   return true;
> +   return ret;
>  }
>  
>  static bool
>  intel_get_boolean(__DRIscreen *psp, int param)
>  {
>     int value = 0;
> -   return intel_get_param(psp, param, &value) && value;
> +   return (intel_get_param(psp, param, &value) == 0) && value;
>  }
>  
>  static void
> @@ -1089,12 +1088,12 @@ intel_detect_sseu(struct intel_screen *intelScreen)
>  
>     ret = intel_get_param(intelScreen->driScrnPriv, I915_PARAM_SUBSLICE_TOTAL,
>                           &intelScreen->subslice_total);
> -   if (ret != -EINVAL)
> +   if (ret < 0 && ret != -EINVAL)
>        goto err_out;
>  
>     ret = intel_get_param(intelScreen->driScrnPriv,
>                           I915_PARAM_EU_TOTAL, &intelScreen->eu_total);
> -   if (ret != -EINVAL)
> +   if (ret < 0 && ret != -EINVAL)
>        goto err_out;
>  
>     /* Without this information, we cannot get the right Braswell brandstrings,
> @@ -1110,7 +1109,7 @@ intel_detect_sseu(struct intel_screen *intelScreen)
>  err_out:
>     intelScreen->subslice_total = -1;
>     intelScreen->eu_total = -1;
> -   _mesa_warning(NULL, "Failed to query GPU properties.\n");
> +   _mesa_warning(NULL, "Failed to query GPU properties (%d).\n", ret);
>  }
>  
>  static bool
>