[igt-dev] [PATCH i-g-t 1/3] tests/kms_dp_tiled_display: Fix bogus abs()

[Manasi Navare]

On Mon, Oct 14, 2019 at 09:13:13PM +0300, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> We're trying to take an absolute value from a unsigned
> number. Fix it.
> 
> And while we're here get rid of the static variables so
> that this can be used for multiple page flips if needed.
> 
> Cc: Madhumitha Tolakanahalli Pradeep <madhumitha.tolakanahalli.pradeep at intel.com>
> Cc: Manasi Navare <manasi.d.navare at intel.com>
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

Looks good to me 

Reviewed-by: Manasi Navare <manasi.d.navare at intel.com>

Manasi

> ---
>  tests/kms_dp_tiled_display.c | 27 ++++++++++++++++-----------
>  1 file changed, 16 insertions(+), 11 deletions(-)
> 
> diff --git a/tests/kms_dp_tiled_display.c b/tests/kms_dp_tiled_display.c
> index dc4866d2f15a..7dde0a7132ed 100644
> --- a/tests/kms_dp_tiled_display.c
> +++ b/tests/kms_dp_tiled_display.c
> @@ -58,6 +58,7 @@ typedef struct {
>  	igt_display_t *display;
>  	data_connector_t *conns;
>  	enum igt_commit_style commit;
> +	struct timeval first_ts;
>  } data_t;
>  
>  static int drm_property_is_tile(drmModePropertyPtr prop)
> @@ -307,10 +308,15 @@ static void page_flip_handler(int fd, unsigned int seq,
>  {
>  	data_t *data = _data;
>  	data_connector_t *conn;
> -	bool is_on_time = false;
> -	static unsigned int _tv_sec, _tv_usec;
> +	struct timeval current_ts = {
> +		.tv_sec = tv_sec,
> +		.tv_usec = tv_usec,
> +	};
>  	int i;
>  
> +	if (!timerisset(&data->first_ts))
> +		data->first_ts = current_ts;
> +
>  	igt_debug("Page Flip Event received from CRTC:%d at %u:%u\n", crtc_id,
>  		  tv_sec, tv_usec);
>  
> @@ -318,24 +324,22 @@ static void page_flip_handler(int fd, unsigned int seq,
>  
>  		conn = &data->conns[i];
>  		if (data->display->pipes[conn->pipe].crtc_id == crtc_id) {
> +			struct timeval diff;
> +			long usec;
> +
>  			igt_assert_f(!conn->got_page_flip,
>  				     "Got two page-flips for CRTC %u\n",
>  				     crtc_id);
>  			conn->got_page_flip = true;
>  
> -			/* Skip the following checks for the first page flip event */
> -			if (_tv_sec == 0 || _tv_usec == 0) {
> -				_tv_sec = tv_sec;
> -				_tv_usec = tv_usec;
> -				return;
> -			}
> +			timersub(&current_ts, &data->first_ts, &diff);
> +			usec = diff.tv_sec * 1000000 + diff.tv_usec;
> +
>  			/*
>  			 * For seamless tear-free display, the page flip event timestamps
>  			 * from all the tiles should not differ by more than 10us.
>  			 */
> -			is_on_time = tv_sec == _tv_sec && (abs(tv_usec - _tv_usec) < 10);
> -
> -			igt_fail_on_f(!is_on_time, "Delayed page flip event from CRTC:%d at %u:%u\n",
> +			igt_fail_on_f(abs(usec) >= 10, "Delayed page flip event from CRTC:%d at %u:%u\n",
>  				      crtc_id, tv_sec, tv_usec);
>  			return;
>  		}
> @@ -394,6 +398,7 @@ igt_main
>  		get_connectors(&data);
>  		setup_mode(&data);
>  		setup_framebuffer(&data);
> +		timerclear(&data.first_ts);
>  		igt_display_commit_atomic(data.display, DRM_MODE_ATOMIC_NONBLOCK |
>  					  DRM_MODE_PAGE_FLIP_EVENT, &data);
>  		while (!got_all_page_flips(&data)) {
> -- 
> 2.21.0
>