[Intel-gfx] [PATCH i-g-t 1/3] lib/igt_kms: Drop all stale events on first commit.

[Chris Wilson]

Quoting Maarten Lankhorst (2017-12-07 13:40:25)
> I've been trying to make kms_cursor_legacy work when subtests fail.
> Other subtests will start failing too because of expired events or
> stale pipe crc. The latter can be resolved in the test, but the former
> could affect other tests
> 
> Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> ---
>  lib/igt_kms.c | 39 ++++++++++++++++++++++++++++++++++++++-
>  lib/igt_kms.h |  1 +
>  2 files changed, 39 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/igt_kms.c b/lib/igt_kms.c
> index 223dbe4ca565..9e14f071ea57 100644
> --- a/lib/igt_kms.c
> +++ b/lib/igt_kms.c
> @@ -2943,7 +2943,10 @@ display_commit_changed(igt_display_t *display, enum igt_commit_style s)
>                         output->changed &= 1 << IGT_CONNECTOR_CRTC_ID;
>         }
>  
> -       display->first_commit = false;
> +       if (display->first_commit) {
> +               igt_display_drop_events(display);
> +               display->first_commit = false;
> +       }

So I spent quite a bit of time debating whether there is merit in "do
something; set-first-mode" that this would then clobber. After some
thought, no that doesn't seem like a wise test construction. I would
however suggest that we igt_debug() if we drop any events here.
-Chris