[igt-dev] [PATCH i-g-t 2/2] tests/kms_big_fb: Delay the expensive big fb creation until the last moment

[Ville Syrjala]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

We already perform the format+mod+rotation test using the small fb, so
we don't actually need to create the big fb until that test has been
performed. We do need to calculate the big fb dimensions though so that
we can calculate the coordinates we're going to use in the test.

$ time kms_big_fb
- real    0m52.902s
+ real    0m52.616s
so not so great.

But if I run each subtest separately it starts to add up:
$ for i in `kms_big_fb --l` ; do kms_big_fb --r $i ; done
- real    5m32.898s
+ real    4m32.164s

The big difference between those two ways of running the test
is at least partially due to the test reusing big fb between
the different rotation subtests for each format+mod combo.
Running each subtest individually can't get that benefit so
avoiding needless big fb creation starts to make a difference.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 tests/kms_big_fb.c | 77 ++++++++++++++++++++++++----------------------
 1 file changed, 41 insertions(+), 36 deletions(-)

diff --git a/tests/kms_big_fb.c b/tests/kms_big_fb.c
index c3520e225ab9..b8813a333643 100644
--- a/tests/kms_big_fb.c
+++ b/tests/kms_big_fb.c
@@ -43,6 +43,7 @@ typedef struct {
 	int width, height;
 	igt_rotation_t rotation;
 	int max_fb_width, max_fb_height;
+	int big_fb_width, big_fb_height;
 	uint64_t ram_size, aper_size, mappable_size;
 	igt_render_copyfunc_t render_copy;
 	drm_intel_bufmgr *bufmgr;
@@ -186,13 +187,32 @@ static void max_fb_size(data_t *data, int *width, int *height,
 		 *width, *height);
 }
 
+static void prep_fb(data_t *data)
+{
+	if (data->big_fb.fb_id)
+		return;
+
+	igt_create_fb(data->drm_fd,
+		      data->big_fb_width, data->big_fb_height,
+		      data->format, data->modifier,
+		      &data->big_fb);
+
+	generate_pattern(data, &data->big_fb, 640, 480);
+}
+
+static void cleanup_fb(data_t *data)
+{
+	igt_remove_fb(data->drm_fd, &data->big_fb);
+	data->big_fb.fb_id = 0;
+}
+
 static bool test_plane(data_t *data)
 {
 	igt_plane_t *plane = data->plane;
 	struct igt_fb *small_fb = &data->small_fb;
 	struct igt_fb *big_fb = &data->big_fb;
-	int w = big_fb->width - small_fb->width;
-	int h = big_fb->height - small_fb->height;
+	int w = data->big_fb_width - small_fb->width;
+	int h = data->big_fb_height - small_fb->height;
 	struct {
 		int x, y;
 	} coords[] = {
@@ -235,16 +255,6 @@ static bool test_plane(data_t *data)
 			y &= ~1;
 		}
 
-		/*
-		 * Make a 1:1 copy of the desired part of the big fb
-		 * rather than try to render the same pattern (translated
-		 * accordinly) again via cairo. Something in cairo's
-		 * rendering pipeline introduces slight differences into
-		 * the result if we try that, and so the crc will not match.
-		 */
-		copy_pattern(data, small_fb, 0, 0, big_fb, x, y,
-			     small_fb->width, small_fb->height);
-
 		igt_plane_set_fb(plane, small_fb);
 		igt_plane_set_size(plane, data->width, data->height);
 
@@ -262,6 +272,22 @@ static bool test_plane(data_t *data)
 			return false;
 		}
 
+		/*
+		 * To speed up skips we delay the big fb creation until
+		 * the above rotation related check has been performed.
+		 */
+		prep_fb(data);
+
+		/*
+		 * Make a 1:1 copy of the desired part of the big fb
+		 * rather than try to render the same pattern (translated
+		 * accordinly) again via cairo. Something in cairo's
+		 * rendering pipeline introduces slight differences into
+		 * the result if we try that, and so the crc will not match.
+		 */
+		copy_pattern(data, small_fb, 0, 0, big_fb, x, y,
+			     small_fb->width, small_fb->height);
+
 		igt_display_commit2(&data->display, data->display.is_atomic ?
 				    COMMIT_ATOMIC : COMMIT_UNIVERSAL);
 
@@ -352,6 +378,9 @@ static bool test_pipe(data_t *data)
 
 static void test_scanout(data_t *data)
 {
+	max_fb_size(data, &data->big_fb_width, &data->big_fb_height,
+		    data->format, data->modifier);
+
 	for_each_pipe_with_valid_output(&data->display, data->pipe, data->output) {
 		if (test_pipe(data))
 			return;
@@ -361,29 +390,6 @@ static void test_scanout(data_t *data)
 	igt_skip("unsupported configuration\n");
 }
 
-static void prep_fb(data_t *data)
-{
-	int width, height;
-
-	if (data->big_fb.fb_id)
-		return;
-
-	max_fb_size(data, &width, &height,
-		    data->format, data->modifier);
-
-	igt_create_fb(data->drm_fd, width, height,
-		      data->format, data->modifier,
-		      &data->big_fb);
-
-	generate_pattern(data, &data->big_fb, 640, 480);
-}
-
-static void cleanup_fb(data_t *data)
-{
-	igt_remove_fb(data->drm_fd, &data->big_fb);
-	data->big_fb.fb_id = 0;
-}
-
 static void
 test_size_overflow(data_t *data)
 {
@@ -650,7 +656,6 @@ igt_main
 					      formats[j].bpp, rotations[k].angle) {
 					igt_require(igt_fb_supported_format(data.format));
 					igt_require(igt_display_has_format_mod(&data.display, data.format, data.modifier));
-					prep_fb(&data);
 					test_scanout(&data);
 				}
 			}
-- 
2.21.0