1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
|
# HG changeset patch
# User Robert Mader <robert.mader@posteo.de>
# Date 1640087004 0
# Node ID 620f6d66f586a8f0efad2f58f7cb5db67f6b318b
# Parent 71184b9b6cb5f44580492b8f508b9363251111d3
Bug 1744896 - Create WaylandVsyncSource on window creation, r=stransky, a=dsmith
Previously we created the `WaylandVsyncSource` when calling
`WaylandStartVsync()` for the first time. Over a couple of refactorings,
this moved from `Create()` to happen much later in the process,
eventually racing with the content process which triggeres `VsyncParent`
to call `GetVsyncSource()`.
If the race went badly, `GetVsyncSource()` would return a `nullptr` and
the tab(s) in question would stick to the global software vsync source.
To avoid that, create the `WaylandVsyncSource` in `Create()` again.
Differential Revision: https://phabricator.services.mozilla.com/D134253
diff -up a/widget/gtk/nsWindow.cpp.1744896 b/widget/gtk/nsWindow.cpp
--- a/widget/gtk/nsWindow.cpp.1744896 2021-12-23 11:54:31.522539340 +0100
+++ b/widget/gtk/nsWindow.cpp 2021-12-23 11:55:56.070270174 +0100
@@ -5765,6 +5765,17 @@ nsresult nsWindow::Create(nsIWidget* aPa
}
}
#endif
+#ifdef MOZ_WAYLAND
+ // Initialize the window specific VsyncSource early in order to avoid races
+ // with BrowserParent::UpdateVsyncParentVsyncSource().
+ // Only use for toplevel windows for now, see bug 1619246.
+ if (GdkIsWaylandDisplay() &&
+ StaticPrefs::widget_wayland_vsync_enabled_AtStartup() &&
+ mWindowType == eWindowType_toplevel) {
+ mWaylandVsyncSource = new WaylandVsyncSource();
+ MOZ_RELEASE_ASSERT(mWaylandVsyncSource);
+ }
+#endif
// We create input contexts for all containers, except for
// toplevel popup windows
@@ -6077,19 +6088,12 @@ void nsWindow::ResumeCompositorFromCompo
void nsWindow::WaylandStartVsync() {
#ifdef MOZ_WAYLAND
- // only use for toplevel windows for now - see bug 1619246
- if (!GdkIsWaylandDisplay() ||
- !StaticPrefs::widget_wayland_vsync_enabled_AtStartup() ||
- mWindowType != eWindowType_toplevel) {
+ if (!mWaylandVsyncSource) {
return;
}
LOG("nsWindow::WaylandStartVsync() [%p]\n", (void*)this);
- if (!mWaylandVsyncSource) {
- mWaylandVsyncSource = new WaylandVsyncSource();
- }
-
WaylandVsyncSource::WaylandDisplay& display =
static_cast<WaylandVsyncSource::WaylandDisplay&>(
mWaylandVsyncSource->GetGlobalDisplay());
|