[Mesa-dev] [PATCH] radv: do not allocate CMASK or DCC for small surfaces

[Samuel Pitoiset]

The idea is ported from RadeonSI, but using 512x512 instead of
256x256 seems slightly better. This improves dota2 performance
by +2%.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
---
 src/amd/vulkan/radv_image.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/amd/vulkan/radv_image.c b/src/amd/vulkan/radv_image.c
index c241e369b9..1bf2fa12ed 100644
--- a/src/amd/vulkan/radv_image.c
+++ b/src/amd/vulkan/radv_image.c
@@ -805,6 +805,16 @@ radv_image_alloc_htile(struct radv_image *image)
 static inline bool
 radv_image_can_enable_dcc_or_cmask(struct radv_image *image)
 {
+	if (image->info.samples <= 1 &&
+	    image->info.width <= 512 && image->info.height <= 512) {
+		/* Do not enable CMASK or DCC for small surfaces where the cost
+		 * of the eliminate pass can be higher than the benefit of fast
+		 * clear. RadeonSI does this, but the image threshold is
+		 * different.
+		 */
+		return false;
+	}
+
 	return image->usage & VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT &&
 	       (image->exclusive || image->queue_family_mask == 1);
 }
-- 
2.15.0