From 5703fc058efdafcdd6b70776ee562478f0753acb Mon Sep 17 00:00:00 2001
From: Ian Forbes <ian.forbes@broadcom.com>
Date: Thu, 28 Mar 2024 14:07:16 -0500
Subject: [PATCH] drm/vmwgfx: Don't memcmp equivalent pointers
These pointers are frequently the same and memcmp does not compare the
pointers before comparing their contents so this was wasting cycles
comparing 16 KiB of memory which will always be equal.
Fixes: bb6780aa5a1d ("drm/vmwgfx: Diff cursors when using cmds")
Signed-off-by: Ian Forbes <ian.forbes@broadcom.com>
Signed-off-by: Zack Rusin <zack.rusin@broadcom.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240328190716.27367-1-ian.forbes@broadcom.com
---
drivers/gpu/drm/vmwgfx/vmwgfx_kms.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
index 9532258a0848c..00c4ff6841301 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
@@ -224,7 +224,7 @@ static bool vmw_du_cursor_plane_has_changed(struct vmw_plane_state *old_vps,
new_image = vmw_du_cursor_plane_acquire_image(new_vps);
changed = false;
- if (old_image && new_image)
+ if (old_image && new_image && old_image != new_image)
changed = memcmp(old_image, new_image, size) != 0;
return changed;
--
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