tests/pm_pc8: try to reuse FBs when possible

Instead of creating a new FB every time we need one, create a cache of
FBs and reuse whenever possible. That means we'll create at most two
FBs, and reuse them hundreds and hundreds of times.

The kmstest_paint_test_pattern function takes about 1-2 seconds to
run, and we'll avoid it whenever we reuse the FB.

This makes the time taken to run the modeset-lpsp-stress subtest go
from 2:29 to 1:29.

A full "time ./pm_pc8 --quick" goes from 8:14 to 6:27.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>

diff --git a/tests/pm_pc8.c b/tests/pm_pc8.c
index cabf005..152c61a 100644 (file)
--- a/tests/pm_pc8.c
+++ b/tests/pm_pc8.c
@@ -84,6 +84,7 @@ enum screen_type {
 int drm_fd, msr_fd, pm_status_fd, pc8_status_fd;
 bool has_runtime_pm, has_pc8;
 struct mode_set_data ms_data;
+struct scanout_fb *fbs = NULL;
 
 /* Stuff used when creating FBs and mode setting. */
 struct mode_set_data {
@@ -103,6 +104,15 @@ struct compare_data {
        drmModePropertyBlobPtr edids[MAX_CONNECTORS];
 };
 
+/* During the stress tests we want to be as fast as possible, so use pre-created
+ * FBs instead of creating them again and again. */
+struct scanout_fb {
+       uint32_t handle;
+       int width;
+       int height;
+       struct scanout_fb *next;
+};
+
 /* If the read fails, then the machine doesn't support PC8+ residencies. */
 static bool supports_pc8_plus_residencies(void)
 {
@@ -249,17 +259,46 @@ static void disable_all_screens(struct mode_set_data *data)
        }
 }
 
-static uint32_t create_fb(struct mode_set_data *data, int width, int height)
+static struct scanout_fb *create_fb(struct mode_set_data *data, int width,
+                                   int height)
 {
+       struct scanout_fb *fb_info;
        struct kmstest_fb fb;
        cairo_t *cr;
-       uint32_t buffer_id;
 
-       buffer_id = kmstest_create_fb(drm_fd, width, height, 32, 24, false,
-                                     &fb);
+       fb_info = malloc(sizeof(struct scanout_fb));
+       igt_assert(fb_info);
+
+       fb_info->handle = kmstest_create_fb(drm_fd, width, height, 32, 24,
+                                           false, &fb);
+       fb_info->width = width;
+       fb_info->height = height;
+       fb_info->next = NULL;
+
        cr = kmstest_get_cairo_ctx(drm_fd, &fb);
        kmstest_paint_test_pattern(cr, width, height);
-       return buffer_id;
+       return fb_info;
+}
+
+static uint32_t get_fb(struct mode_set_data *data, int width, int height)
+{
+       struct scanout_fb *fb;
+
+       if (!fbs) {
+               fbs = create_fb(data, width, height);
+               return fbs->handle;
+       }
+
+       for (fb = fbs; fb != NULL; fb = fb->next) {
+               if (fb->width == width && fb->height == height)
+                       return fb->handle;
+
+               if (!fb->next) {
+                       fb->next = create_fb(data, width, height);
+                       return fb->next->handle;
+               }
+       }
+       igt_assert(false);
 }
 
 static bool enable_one_screen_with_type(struct mode_set_data *data,
@@ -291,7 +330,7 @@ static bool enable_one_screen_with_type(struct mode_set_data *data,
                return false;
 
        crtc_id = data->res->crtcs[0];
-       buffer_id = create_fb(data, mode->hdisplay, mode->vdisplay);
+       buffer_id = get_fb(data, mode->hdisplay, mode->vdisplay);
 
        igt_assert(crtc_id);
        igt_assert(buffer_id);
@@ -724,6 +763,15 @@ static void setup_environment(void)
 
 static void teardown_environment(void)
 {
+       struct scanout_fb *fb, *fb_next;
+
+       fb = fbs;
+       while (fb) {
+               fb_next = fb->next;
+               free(fb);
+               fb = fb_next;
+       }
+
        fini_mode_set_data(&ms_data);
        drmClose(drm_fd);
        close(msr_fd);