[igt-dev] [PATCH i-g-t] lib/drmtest: Don't log a warning when drm driver is not loaded

[Petri Latvala]

On Tue, Aug 02, 2022 at 11:27:56AM +0200, Zbigniew Kempczyński wrote:
> Some drivers left machine with drm driver unloaded. When IGT_DEVICE is
> set first call to __get_card_for_nth_filter() won't find the drm device
> and outputs a warning.  Lets avoid logging a warning when we're not sure
> drm driver is loaded.
> 
> Fixes: https://gitlab.freedesktop.org/drm/intel/-/issues/6498
> 
> Signed-off-by: Zbigniew Kempczyński <zbigniew.kempczynski at intel.com>
> Cc: Petri Latvala <petri.latvala at intel.com>
> ---
>  lib/drmtest.c | 14 +++++++++-----
>  1 file changed, 9 insertions(+), 5 deletions(-)
> 
> diff --git a/lib/drmtest.c b/lib/drmtest.c
> index 4f9d8a11cb..58d2f7f998 100644
> --- a/lib/drmtest.c
> +++ b/lib/drmtest.c
> @@ -348,12 +348,15 @@ static int __open_driver_exact(const char *name, unsigned int chipset)
>   *
>   * @card: pointer to the igt_device_card structure to be filled
>   * when a card is found.
> + * @do_warn: write out a warning when filter cannot match the device. Used for
> + * case when drm module is not loaded but filter (IGT_DEVICE) is set.
>   *
>   * Returns:
>   * True if card according to the added filter was found,
>   * false othwerwise.
>   */
> -static bool __get_card_for_nth_filter(int idx, struct igt_device_card *card)
> +static bool __get_card_for_nth_filter(int idx, struct igt_device_card *card,
> +				      bool do_warn)
>  {
>  	const char *filter;
>  
> @@ -366,7 +369,8 @@ static bool __get_card_for_nth_filter(int idx, struct igt_device_card *card)
>  			return true;
>  		}
>  
> -		igt_warn("No card matches the filter!\n");
> +		if (do_warn)
> +			igt_warn("No card matches the filter!\n");
>  	}
>  
>  	return false;
> @@ -434,11 +438,11 @@ int __drm_open_driver_another(int idx, int chipset)
>  		struct igt_device_card card;
>  		bool found;
>  
> -		found = __get_card_for_nth_filter(idx, &card);
> +		found = __get_card_for_nth_filter(idx, &card, false);
>  
>  		if (!found) {
>  			drm_load_module(chipset);
> -			found = __get_card_for_nth_filter(idx, &card);
> +			found = __get_card_for_nth_filter(idx, &card, true);

If you make get_card_for_nth warn here, you get the warning
twice. There's a warning printed three lines below (outside of this
diff's context).

>  		}
>  
>  		if (!found || !strlen(card.card))
> @@ -483,7 +487,7 @@ int __drm_open_driver_render(int chipset)
>  		struct igt_device_card card;
>  		bool found;
>  
> -		found = __get_card_for_nth_filter(0, &card);
> +		found = __get_card_for_nth_filter(0, &card, true);

This is the only call site that needs 'true'. Making me think whether
it's cleaner to just remove the warning from get_card_for_nth
altogether and just add it here.


-- 
Petri Latvala


>  
>  		if (!found || !strlen(card.render))
>  			return -1;
> -- 
> 2.34.1
>