6.6-stable review patch. If anyone has any objections, please let me know.
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From: Ian Forbes ian.forbes@broadcom.com
[ Upstream commit 5703fc058efdafcdd6b70776ee562478f0753acb ]
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.for... Signed-off-by: Sasha Levin sashal@kernel.org --- 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 93e2a27daed0c..08f2470edab27 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c @@ -216,7 +216,7 @@ 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;