From d108c2c82cba242ea5998d7c91254d90d3a5db71 Mon Sep 17 00:00:00 2001 From: Olivier Fourdan Date: Fri, 11 Sep 2020 11:30:18 +0200 Subject: [PATCH xserver 10/16] xwayland: Do not discard frame callbacks on allow commits MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Currently, when a X11 client (usually the X11 window manager from a Wayland compositor) changes the value of the X11 property `_XWAYLAND_ALLOW_COMMITS` from `false` to `true`, all pending frame callbacks on the window are discarded so that the commit occurs immediately. Weston uses that mechanism to prevent the content of the window from showing before it's ready when mapping the window initially, but discarding the pending frame callbacks has no effect on the initial mapping of the X11 window since at that point there cannot be any frame callback on a surface which hasn't been committed yet anyway. However, discarding pending frame callbacks can be problematic if we were to use the same `_XWAYLAND_ALLOW_COMMITS` mechanism to prevent damages to be posted before the X11 toplevel is updated completely (including the window decorations from the X11 window manager). Remove the portion of code discarding the pending frame callback, Xwayland should always wait for a pending frame callback if there's one before posting new damages. Signed-off-by: Olivier Fourdan Reviewed-by: Pekka Paalanen Reviewed-by: Michel Dänzer https://gitlab.freedesktop.org/xorg/xserver/merge_requests/333 (cherry picked from commit 66da95a172c4941b75ffedcdaa0138c0a48f11fb) --- hw/xwayland/xwayland.c | 13 ------------- 1 file changed, 13 deletions(-) diff --git a/hw/xwayland/xwayland.c b/hw/xwayland/xwayland.c index d02934cd5..a69188c0f 100644 --- a/hw/xwayland/xwayland.c +++ b/hw/xwayland/xwayland.c @@ -193,8 +193,6 @@ static void xwl_window_property_allow_commits(struct xwl_window *xwl_window, PropertyStateRec *propstate) { - Bool old_allow_commits = xwl_window->allow_commits; - switch (propstate->state) { case PropertyNewValue: xwl_window_set_allow_commits_from_property(xwl_window, propstate->prop); @@ -207,17 +205,6 @@ xwl_window_property_allow_commits(struct xwl_window *xwl_window, default: break; } - - /* If allow_commits turned from off to on, discard any frame - * callback we might be waiting for so that a new buffer is posted - * immediately through block_handler() if there is damage to post. - */ - if (!old_allow_commits && xwl_window->allow_commits) { - if (xwl_window->frame_callback) { - wl_callback_destroy(xwl_window->frame_callback); - xwl_window->frame_callback = NULL; - } - } } static void -- 2.28.0