Add support for DRM leasing and significantly rework composition code

* 12to11.c (HandleCmdline): Improve messages printed during
-help.
(XLMain): Initialize DRM leasing.
* 12to11.man: Document changes.
* Imakefile (LOCAL_LIBRARIES): Add xcb-randr, xf86drm and
XPresent.
(SRCS): Add drm_lease.c.
(OBJS): Add drm_lease.o.
* atoms.c (names): Add CONNECTOR_ID.
(CONNECTOR_ID): New atom.
(XLInitAtoms): Intern CONNECTOR_ID.
* compositor.h (struct _RenderFuncs): Require event mask to be
passed to target_from_window.  New functions
`set_standard_event_mask', `present_to_window',
`cancel_presentation_callback', and `cancel_presentation'.
(struct _BufferFuncs): Move buffer release machinery here.
(enum _FrameMode): New enum.
* egl.c (TargetFromWindow, SetStandardEventMask,
egl_render_funcs): Adjust functions accordingly.
* frame_clock.c (struct _FrameClock): New fields
`end_frame_called' and `pending_sync_value'.
(HandleEndFrame, PostEndFrame, StartFrame, EndFrame): Clean up
frame synchronization code.  Do not end upon predicted
presentation time if EndFrame was not called in time.
(FreezeForValue): New function.
(XLFrameClockHandleFrameEvent): Defer actually freezing until
StartFrame happens.
(XLFrameClockGetFrameTime): New function.
* icon_surface.c (ReleaseBuffer): Use RenderWaitForIdle.
(RunFrameCallbacks, AfterFrame): Pass frame clock to callbacks.
Use frame time if available.
(XLGetIconSurface): Require wait_for_idle to work.
* output.c (change_hook): New hook.
(XLHandleOneXEventForOutputs): Run hook if set.
(XLOutputSetChangeFunction): New function.
(XLInitRROutputs): Select for RRResourceChangeNotify if
providers are supported.
* picture_renderer.c (struct _PresentRecord)
(struct _BufferActivityRecord, struct _IdleCallback)
(struct _PictureBuffer, struct _PictureTarget)
(struct _DrmFormatInfo, struct _DmaBufRecord)
(struct _PresentCompletionCallback): New record structures.
(all_formats, SendRoundtripMessage, FindBufferActivityRecord)
(RecordBufferActivity, RunIdleCallbacks, MaybeRunIdleCallbacks)
(UnlinkActivityRecord, HandleActivityEvent, InitRenderFuncs)
(TargetFromDrawable, TargetFromPixmap, TargetFromWindow)
(SetStandardEventMask, NoteTargetSize, PictureFromTarget)
(DestroyRenderTarget, FillBoxesWithTransparency)
(ServerRegionFromRegion, ClearRectangle, Composite)
(FindPresentRecord, AllocateRecord, PresentToWindow)
(CancelPresentationCallback, CancelPresentation)
(picture_render_funcs, FindSupportedModifiers, InitDrmFormats)
(PictFormatIsPresentable, BufferFromDmaBuf, FinishDmaBufRecord)
(BufferFromDmaBufAsync, BufferFromShm, BufferFromSinglePixel)
(FreeShmBuffer, FreeDmabufBuffer, FreeSinglePixelBuffer)
(AddIdleCallback, CancelIdleCallback, IsBufferIdle)
(IdleEventPredicate, WaitForIdle, SetNeedWaitForIdle)
(picture_buffer_funcs, HandlePresentCompleteNotify)
(HandlePresentIdleNotify, HandlePresentationEvent)
(HandleOneXEventForPictureRenderer, InitPictureRenderer): Allow
presenting pixmaps directly, and move buffer release tracking
machinery here.
* renderer.c (RenderTargetFromWindow): Update signature.
(RenderPresentToWindow, RenderCancelPresentationCallback)
(RenderCancelPresentation, RenderAddIdleCallback)
(RegisterStaticRenderer): New wrapper functions.
* run.c (HandleOneXEvent): Handle picture renderer events
earlier.
* seat.c (MaybeCreateCursor): Require wait_for_idle.
(ReleaseBuffer): Wait for buffer to become idle on each target
in the cursor ring.
* subcompositor.c (struct _Subcompositor): New callback
`note_frame'.
(SubcompositorSetNoteFrameCallback, NoViewsAfter)
(PresentCompletedCallback): New functions.
(SubcompositorUpdate): Try to present the buffer if possible,
and run completion callbacks.
(SubcompositorFree): Free presentation key.
* surface.c (XLSurfaceRunFrameCallbacksMs): New function.
* text_input.c: Improve commentary.
* xdg-shell.xml: Update from wayland-protocols.
* xdg_surface.c (struct _XdgRole): New fields `pending_frame',
`last_specified_serial'.
(struct _ReleaseLaterRecord): Replace free function with idle
callback key and xdg role pointers.
(RemoveRecord): Delete function.
(FreeRecords): Stop cancelling buffer destroy listener.
(ReleaseLaterExtBufferFunc): Delete function.
(RunFrameCallbacks): Use frame clock time if it is set.
(HandleReleaseLaterMessage): Delete function.
(BufferIdleCallback): New function.
(ReleaseLater): Delete function.
(XLHandleXEventForXdgSurfaces): Stop handling buffer release
events here.
(AckConfigure): Improve debug code and reject duplicate serials.
(Commit): Unfreeze earlier; also, in general...
(NoteFrame): Move frame handling implementation here.
(ReleaseBuffer, Subframe, EndSubframe, AfterFrame, ResizeForMap)
(SelectExtraEvents): Set standard event mask.
(XLGetXdgSurface, XLXdgRoleSendConfigure): ...Replace frame
clock logic with that in NoteFrame.

12to11.c

@@ -98,7 +98,7 @@ HandleCmdline (Display *dpy, int argc, char **argv)
 	{
 	print_usage:
 	  fprintf (stderr,
-		   "usage: %s [-name name] [-class class] [-xrm resourcestring]...\n",
+		   "usage: %s [-name name] [-class class] [-xrm resourcestring...]\n",
 		   argv[0]);
 	  exit (!strcmp (argv[i], "-help") ? 0 : 1);
 	}
@@ -224,6 +224,7 @@ XLMain (int argc, char **argv)
   XLInitDecoration ();
   XLInitTextInput ();
   XLInitSinglePixelBuffer ();
+  XLInitDrmLease ();
 
   /* This has to come after the rest of the initialization.  */
   DetermineServerTime ();

12to11.man

@@ -3,7 +3,7 @@
 12to11 - Wayland to X protocol translator
 .SH SYNOPSIS
 .B 12to11
-[\-\fBclass\fP \fIclass\fP] [\-\fBname\fP \fIname\fP] [\-\fBxrm\fP \fIresourcestring\fP]...
+[\-\fBclass\fP \fIclass\fP] [\-\fBname\fP \fIname\fP] [\-\fBxrm\fP \fIresourcestring\fP...]
 .SH DESCRIPTION
 .I 12to11
 starts a Wayland compositor on the next available socket;
@@ -212,6 +212,16 @@ Protocol	Version
 zwp_linux_explicit_synchronization_v1	2
 .TE
 .PP
+When the X server supports version 1.6 or later of the X Resize,
+Rotate and Reflect Extension, the following Wayland protocol is also
+supported:
+.TS H
+lb lb
+lb n .
+Protocol	Version
+wp_drm_lease_device_v1	1
+.TE
+.PP
 However, Wayland clients are allowed to continue to access data from
 the \fBCLIPBOARD\fP and \fBPRIMARY\fP selections even when they do not
 have the keyboard focus, against the restrictions put out in the
@@ -242,5 +252,5 @@ vast majority of clients seem not to make use of this feature, and
 implementing it would be a lot of trouble.
 .SH "SEE ALSO"
 X(7), Xorg(1)
-.SH AUTHOR
+.SH AUTHORS
 Various contributors.

Imakefile

@@ -1,4 +1,4 @@
-#include "libraries.def"
+#include "12to11.conf"
 
 #ifndef HasPosixThreads
 #error "Posix threads are required"
@@ -10,7 +10,8 @@ DEPLIBS = $(DEPXLIB) $(DEPEXTENSIONLIB) $(DEPXRANDRLIB) $(DEPXRENDERLIB) \
 
 LOCAL_LIBRARIES = $(XLIB) $(EXTENSIONLIB) $(XCBLIB) $(XCB) $(XCB_SHM)      \
   $(XRANDRLIB) $(PIXMAN) $(XRENDERLIB) $(XILIB) $(XKBFILELIB) $(XFIXESLIB) \
-  $(XCB_DRI3) $(XCB_SHAPE) $(WAYLAND_SERVER)
+  $(XCB_DRI3) $(XCB_SHAPE) $(WAYLAND_SERVER) $(XCB_RANDR) $(DRM)           \
+  $(XPRESENTLIB)
 
 INCLUDES := $(DRMINCLUDES) $(PIXMANINCLUDES)
 
@@ -22,7 +23,7 @@ SRCS = 12to11.c run.c alloc.c fns.c output.c compositor.c       \
   icon_surface.c primary_selection.c renderer.c                 \
   picture_renderer.c explicit_synchronization.c transform.c     \
   wp_viewporter.c decoration.c text_input.c                     \
-  single_pixel_buffer.c
+  single_pixel_buffer.c drm_lease.c
 
 OBJS = 12to11.o run.o alloc.o fns.o output.o compositor.o       \
   surface.o region.o shm.o atoms.o subcompositor.o positioner.o \
@@ -32,7 +33,7 @@ OBJS = 12to11.o run.o alloc.o fns.o output.o compositor.o       \
   icon_surface.o primary_selection.o renderer.o                 \
   picture_renderer.o explicit_synchronization.o transform.o     \
   wp_viewporter.o decoration.o text_input.o                     \
-  single_pixel_buffer.o
+  single_pixel_buffer.o drm_lease.o
 
 GENHEADERS = transfer_atoms.h
 
@@ -115,6 +116,7 @@ ScannerTarget(viewporter)
 ScannerTarget(xdg-decoration-unstable-v1)
 ScannerTarget(text-input-unstable-v3)
 ScannerTarget(single-pixel-buffer-v1)
+ScannerTarget(drm-lease-v1)
 
 /* Make OBJS depend on scanner headers, and depend on both them and SRCS.  */
 $(OBJS): $(GENHEADERS)

atoms.c

@@ -108,6 +108,7 @@ static const char *names[] =
     "_NET_WM_WINDOW_TYPE",
     "_NET_WM_WINDOW_TYPE_MENU",
     "_NET_WM_WINDOW_TYPE_DND",
+    "CONNECTOR_ID",
 
     /* These are automatically generated from mime.txt.  */
     DirectTransferAtomNames
@@ -129,7 +130,8 @@ Atom _NET_WM_OPAQUE_REGION, _XL_BUFFER_RELEASE, _NET_WM_SYNC_REQUEST_COUNTER,
   XdndActionPrivate, XdndActionList, XdndActionDescription, XdndProxy,
   XdndEnter, XdndPosition, XdndStatus, XdndLeave, XdndDrop, XdndFinished,
   _NET_WM_FRAME_TIMINGS, _NET_WM_BYPASS_COMPOSITOR, WM_STATE,
-  _NET_WM_WINDOW_TYPE, _NET_WM_WINDOW_TYPE_MENU, _NET_WM_WINDOW_TYPE_DND;
+  _NET_WM_WINDOW_TYPE, _NET_WM_WINDOW_TYPE_MENU, _NET_WM_WINDOW_TYPE_DND,
+  CONNECTOR_ID;
 
 XrmQuark resource_quark, app_quark, QString;
 
@@ -283,9 +285,10 @@ XLInitAtoms (void)
   _NET_WM_WINDOW_TYPE = atoms[58];
   _NET_WM_WINDOW_TYPE_MENU = atoms[59];
   _NET_WM_WINDOW_TYPE_DND = atoms[60];
+  CONNECTOR_ID = atoms[61];
 
   /* This is automatically generated.  */
-  DirectTransferAtomInit (atoms, 61);
+  DirectTransferAtomInit (atoms, 62);
 
   /* Now, initialize quarks.  */
   resource_quark = XrmPermStringToQuark (compositor.resource_name);

compositor.h

@@ -121,9 +121,15 @@ typedef struct _ShmFormat ShmFormat;
 
 typedef enum _Operation Operation;
 
+typedef void *IdleCallbackKey;
+typedef void *PresentCompletionKey;
+
 typedef void (*DmaBufSuccessFunc) (RenderBuffer, void *);
 typedef void (*DmaBufFailureFunc) (void *);
 
+typedef void (*BufferIdleFunc) (RenderBuffer, void *);
+typedef void (*PresentCompletionFunc) (void *);
+
 enum _Operation
   {
     OperationOver,
@@ -250,11 +256,14 @@ struct _RenderFuncs
   Bool (*init_render_funcs) (void);
 
   /* Create a rendering target for the given window.  */
-  RenderTarget (*target_from_window) (Window);
+  RenderTarget (*target_from_window) (Window, unsigned long);
 
   /* Create a rendering target for the given pixmap.  */
   RenderTarget (*target_from_pixmap) (Pixmap);
 
+  /* Set the standard event mask of the target.  */
+  void (*set_standard_event_mask) (RenderTarget, unsigned long);
+
   /* Set the target width and height.  This can be NULL.  */
   void (*note_target_size) (RenderTarget, int, int);
 
@@ -327,6 +336,22 @@ struct _RenderFuncs
      called.  */
   int (*get_finish_fence) (Bool *);
 
+  /* Directly present the given buffer to the window, without copying,
+     and possibly flip the buffer contents to the screen, all while
+     possibly being synchronized with the vertical refresh.  Call the
+     supplied callback when the presentation completes.  May be
+     NULL.  */
+  PresentCompletionKey (*present_to_window) (RenderTarget, RenderBuffer,
+					     pixman_region32_t *,
+					     PresentCompletionFunc, void *);
+
+  /* Cancel the given presentation callback.  */
+  void (*cancel_presentation_callback) (PresentCompletionKey);
+  
+  /* Cancel any presentation that might have happened to the window
+     backing the given target.  */
+  void (*cancel_presentation) (RenderTarget);
+
   /* Some flags.  NeverAges means targets always preserve contents
      that were previously drawn.  */
   int flags;
@@ -404,6 +429,28 @@ struct _BufferFuncs
      by being copied to an offscreen buffer.  */
   Bool (*can_release_now) (RenderBuffer);
 
+  /* Run a callback once the buffer contents become idle on the given
+     target.  NULL if flags contains ImmediateRelease.  The callback
+     is also run when the buffer is destroyed, but not when the target
+     is destroyed; in that case, the callback key simply becomes
+     invalid.  */
+  IdleCallbackKey (*add_idle_callback) (RenderBuffer, RenderTarget,
+					BufferIdleFunc, void *);
+
+  /* Cancel the given idle callback.  */
+  void (*cancel_idle_callback) (IdleCallbackKey);
+
+  /* Return whether or not the buffer is idle.  NULL if flags contains
+     ImmediateRelease.  */
+  Bool (*is_buffer_idle) (RenderBuffer, RenderTarget);
+
+  /* Wait for a buffer to become idle on the given target.  May be
+     NULL.  */
+  void (*wait_for_idle) (RenderBuffer, RenderTarget);
+
+  /* Ensure wait_for_idle can be called.  May be NULL.  */
+  void (*set_need_wait_for_idle) (RenderTarget);
+
   /* Called during renderer initialization.  */
   void (*init_buffer_funcs) (void);
 };
@@ -414,8 +461,9 @@ extern void RegisterStaticRenderer (const char *, RenderFuncs *,
 				    BufferFuncs *);
 extern void InitRenderers (void);
 
-extern RenderTarget RenderTargetFromWindow (Window);
+extern RenderTarget RenderTargetFromWindow (Window, unsigned long);
 extern RenderTarget RenderTargetFromPixmap (Pixmap);
+extern void RenderSetStandardEventMask (RenderTarget, unsigned long);
 extern void RenderNoteTargetSize (RenderTarget, int, int);
 extern Picture RenderPictureFromTarget (RenderTarget);
 extern void RenderFreePictureFromTarget (Picture);
@@ -432,6 +480,12 @@ extern RenderFence RenderImportFdFence (int, Bool *);
 extern void RenderWaitFence (RenderFence);
 extern void RenderDeleteFence (RenderFence);
 extern int RenderGetFinishFence (Bool *);
+extern PresentCompletionKey RenderPresentToWindow (RenderTarget, RenderBuffer,
+						   pixman_region32_t *,
+						   PresentCompletionFunc,
+						   void *);
+extern void RenderCancelPresentationCallback (PresentCompletionKey);
+extern void RenderCancelPresentation (RenderTarget);
 
 extern DrmFormat *RenderGetDrmFormats (int *);
 extern dev_t RenderGetRenderDevice (Bool *);
@@ -450,6 +504,12 @@ extern void RenderFreeSinglePixelBuffer (RenderBuffer);
 extern void RenderUpdateBufferForDamage (RenderBuffer, pixman_region32_t *,
 					 DrawParams *);
 extern Bool RenderCanReleaseNow (RenderBuffer);
+extern IdleCallbackKey RenderAddIdleCallback (RenderBuffer, RenderTarget,
+					      BufferIdleFunc, void *);
+extern void RenderCancelIdleCallback (IdleCallbackKey);
+extern Bool RenderIsBufferIdle (RenderBuffer, RenderTarget);
+extern void RenderWaitForIdle (RenderBuffer, RenderTarget);
+extern void RenderSetNeedWaitForIdle (RenderTarget);
 
 /* Defined in run.c.  */
 
@@ -610,6 +670,15 @@ typedef struct _View View;
 typedef struct _List List;
 typedef struct _Subcompositor Subcompositor;
 
+typedef enum _FrameMode FrameMode;
+
+enum _FrameMode
+  {
+    ModeStarted,
+    ModeComplete,
+    ModePresented,
+  };
+
 extern void SubcompositorInit (void);
 
 extern Subcompositor *MakeSubcompositor (void);
@@ -634,6 +703,10 @@ extern void SubcompositorSetBoundsCallback (Subcompositor *,
 					    void (*) (void *, int, int,
 						      int, int),
 					    void *);
+extern void SubcompositorSetNoteFrameCallback (Subcompositor *,
+					       void (*) (FrameMode, uint64_t,
+							 void *),
+					       void *);
 extern void SubcompositorBounds (Subcompositor *, int *, int *, int *, int *);
 extern void SubcompositorSetProjectiveTransform (Subcompositor *, int, int);
 
@@ -964,6 +1037,7 @@ extern void XLDefaultCommit (Surface *);
 extern void XLStateAttachBuffer (State *, ExtBuffer *);
 extern void XLStateDetachBuffer (State *);
 extern void XLSurfaceRunFrameCallbacks (Surface *, struct timespec);
+extern void XLSurfaceRunFrameCallbacksMs (Surface *, uint32_t);
 extern CommitCallback *XLSurfaceRunAtCommit (Surface *,
 					     void (*) (Surface *, void *),
 					     void *);
@@ -1004,6 +1078,7 @@ extern Bool XLGetOutputRectAt (int, int, int *, int *, int *, int *);
 extern void *XLAddScaleChangeCallback (void *, void (*) (void *, int));
 extern void XLRemoveScaleChangeCallback (void *);
 extern void XLClearOutputs (Surface *);
+extern void XLOutputSetChangeFunction (void (*) (Time));
 
 /* Defined in atoms.c.  */
 
@@ -1022,7 +1097,8 @@ extern Atom _NET_WM_OPAQUE_REGION, _XL_BUFFER_RELEASE,
   XdndActionAsk, XdndActionPrivate, XdndActionList, XdndActionDescription,
   XdndProxy, XdndEnter, XdndPosition, XdndStatus, XdndLeave, XdndDrop,
   XdndFinished, _NET_WM_FRAME_TIMINGS, _NET_WM_BYPASS_COMPOSITOR, WM_STATE,
-  _NET_WM_WINDOW_TYPE, _NET_WM_WINDOW_TYPE_MENU, _NET_WM_WINDOW_TYPE_DND;
+  _NET_WM_WINDOW_TYPE, _NET_WM_WINDOW_TYPE_MENU, _NET_WM_WINDOW_TYPE_DND,
+  CONNECTOR_ID;
 
 extern XrmQuark resource_quark, app_quark, QString;
 
@@ -1062,6 +1138,7 @@ extern void XLFrameClockSetPredictRefresh (FrameClock *);
 extern void XLFrameClockDisablePredictRefresh (FrameClock *);
 extern void XLFrameClockSetFreezeCallback (FrameClock *, void (*) (void *),
 					   void *);
+extern uint64_t XLFrameClockGetFrameTime (FrameClock *);
 extern void *XLAddCursorClockCallback (void (*) (void *, struct timespec),
 				       void *);
 extern void XLStopCursorClockCallback (void *);
@@ -1477,6 +1554,10 @@ extern void XLInitDecoration (void);
 
 extern void XLInitSinglePixelBuffer (void);
 
+/* Defined in drm_lease.h.  */
+
+extern void XLInitDrmLease (void);
+
 /* Utility functions that don't belong in a specific file.  */
 
 #define ArrayElements(arr) (sizeof (arr) / sizeof (arr)[0])

egl.c

@@ -1077,7 +1077,7 @@ TryPreserveOnSwap (EGLSurface *surface)
 }
 
 static RenderTarget
-TargetFromWindow (Window window)
+TargetFromWindow (Window window, unsigned long standard_event_mask)
 {
   EglTarget *target;
 
@@ -1125,6 +1125,12 @@ TargetFromPixmap (Pixmap pixmap)
   return (RenderTarget) (void *) target;
 }
 
+static void
+SetStandardEventMask (RenderTarget target, unsigned long standard_event_mask)
+{
+  /* Ignored.  */
+}
+
 static void
 NoteTargetSize (RenderTarget target, int width, int height)
 {
@@ -1659,6 +1665,7 @@ static RenderFuncs egl_render_funcs =
     .init_render_funcs = InitRenderFuncs,
     .target_from_window = TargetFromWindow,
     .target_from_pixmap = TargetFromPixmap,
+    .set_standard_event_mask = SetStandardEventMask,
     .note_target_size = NoteTargetSize,
     .picture_from_target = PictureFromTarget,
     .free_picture_from_target = FreePictureFromTarget,

frame_clock.c

@@ -90,6 +90,9 @@ struct _FrameClock
      unfrozen until EndFrame.  */
   Bool need_configure, frozen, frozen_until_end_frame;
 
+  /* Whether or not EndFrame was called after StartFrame.  */
+  Bool end_frame_called;
+
   /* The wanted configure value.  */
   uint64_t configure_id;
 
@@ -111,6 +114,9 @@ struct _FrameClock
 
   /* Data for that callback.  */
   void *freeze_callback_data;
+
+  /* Any pending frame synchronization counter value, or 0.  */
+  uint64_t pending_sync_value;
 };
 
 struct _CursorClockCallback
@@ -221,9 +227,53 @@ HandleEndFrame (Timer *timer, void *data, struct timespec time)
      the frame.  */
   RemoveTimer (timer);
   clock->end_frame_timer = NULL;
+
+  if (clock->end_frame_called)
     EndFrame (clock);
 }
 
+/* Forward declaration.  */
+static void RunFrameCallbacks (FrameClock *);
+
+static void
+FreezeForValue (FrameClock *clock, uint64_t counter_value)
+{
+  /* If it took too long (1 second at 60fps) to obtain the counter
+     value, and said value is now out of date, don't do anything.  */
+
+  if (clock->next_frame_id > counter_value)
+    return;
+
+  /* The frame clock is now frozen, and we will have to wait for a
+     client to ack_configure and then commit something.  */
+
+  if (clock->end_frame_timer)
+    {
+      /* End the frame now, and clear in_frame early.  */
+      RemoveTimer (clock->end_frame_timer);
+      clock->end_frame_timer = NULL;
+
+      if (clock->end_frame_called)
+	EndFrame (clock);
+    }
+
+  /* counter_value - 240 is the value seen by the compositor when the
+     frame contents were frozen in response to a resize.  If it is
+     less than finished_frame_id, run frame callbacks now, or clients
+     like Chromium are confused and hang waiting for frame callbacks
+     to be called.  */
+  if (counter_value - 240 <= clock->finished_frame_id)
+    RunFrameCallbacks (clock);
+
+  /* The reason for clearing in_frame is that otherwise a future
+     Commit after the configuration is acknowledged will not be able
+     to start a new frame and restart the frame clock.  */
+  clock->in_frame = False;
+  clock->need_configure = True;
+  clock->configure_id = counter_value;
+  clock->frozen = True;
+}
+
 static void
 PostEndFrame (FrameClock *clock)
 {
@@ -320,6 +370,9 @@ StartFrame (FrameClock *clock, Bool urgent, Bool predict)
   if (clock->frozen_until_end_frame)
     return;
 
+  if (clock->in_frame)
+    return;
+
   if (clock->need_configure)
     {
       clock->next_frame_id = clock->configure_id;
@@ -327,6 +380,7 @@ StartFrame (FrameClock *clock, Bool urgent, Bool predict)
     }
 
   clock->in_frame = True;
+  clock->end_frame_called = False;
 
   /* Set the clock to an odd value; if we want the compositor to
      redraw this frame immediately (since it is running late), make it
@@ -371,6 +425,10 @@ EndFrame (FrameClock *clock)
 
   clock->frozen_until_end_frame = False;
 
+  /* Signal that end_frame was called and it is now safe to finish the
+     frame from the timer.  */
+  clock->end_frame_called = True;
+
   if (!clock->in_frame
       /* If the end of the frame has already been signalled, this
 	 function should just return instead of increasing the counter
@@ -389,6 +447,12 @@ EndFrame (FrameClock *clock)
   clock->next_frame_id += 1;
   clock->finished_frame_id = clock->next_frame_id;
 
+  /* The frame has ended.  Freeze the frame clock if there is a
+     pending sync value.  */
+  if (clock->pending_sync_value)
+    FreezeForValue (clock, clock->pending_sync_value);
+  clock->pending_sync_value = 0;
+
   if (!frame_sync_supported)
     return;
 
@@ -570,28 +634,15 @@ XLFrameClockHandleFrameEvent (FrameClock *clock, XEvent *event)
       if (value % 2)
 	value += 1;
 
-      /* The frame clock is now frozen, and we will have to wait for a
+      /* If a frame is in progress, postpone this frame
-	 client to ack_configure and then commit something.  */
+	 synchronization message.  */
-
+      if (clock->in_frame && !clock->end_frame_called)
-      if (clock->end_frame_timer)
+	clock->pending_sync_value = value;
-	{
+      else
-	  /* End the frame now, and clear in_frame early.  */
+	FreezeForValue (clock, value);
-	  RemoveTimer (clock->end_frame_timer);
-	  clock->end_frame_timer = NULL;
-	  EndFrame (clock);
-
-	  /* The reason for clearing in_frame is that otherwise a
-	     future Commit after the configuration is acknowledged
-	     will not be able to start a new frame and restart the
-	     frame clock.  */
-	  clock->in_frame = False;
-	}
-
-      clock->need_configure = True;
-      clock->configure_id = value;
-      clock->frozen = True;
 
       if (clock->freeze_callback)
+	/* Call the freeze callback in any case.  */
 	clock->freeze_callback (clock->freeze_callback_data);
     }
 }
@@ -731,6 +782,16 @@ XLFrameClockSetFreezeCallback (FrameClock *clock, void (*callback) (void *),
   clock->freeze_callback_data = data;
 }
 
+uint64_t
+XLFrameClockGetFrameTime (FrameClock *clock)
+{
+  /* Only return the time if it is actually a valid clock time.  */
+  if (!compositor.server_time_monotonic)
+    return 0;
+
+  return clock->last_frame_time;
+}
+
 
 /* Cursor animation clock-related functions.  */
 

icon_surface.c

@@ -155,9 +155,14 @@ Setup (Surface *surface, Role *role)
 static void
 ReleaseBuffer (Surface *surface, Role *role, ExtBuffer *buffer)
 {
+  IconSurface *icon;
+
+  icon = IconSurfaceFromRole (role);
+
   /* Icon surfaces are not supposed to change much, so doing an XSync
-     here is okay.  */
+     (or XIfEvent) here is okay.  */
-  XSync (compositor.display, False);
+  RenderWaitForIdle (XLRenderBufferFromBuffer (buffer),
+		     icon->target);
 
   /* Now really release the buffer.  */
   XLReleaseBuffer (buffer);
@@ -213,17 +218,25 @@ NoteBounds (void *data, int min_x, int min_y, int max_x, int max_y)
 }
 
 static void
-RunFrameCallbacks (Surface *surface)
+RunFrameCallbacks (Surface *surface, FrameClock *clock)
 {
   struct timespec time;
+  uint64_t last_drawn_time;
 
   /* Surface can be NULL for various reasons, especially events
      arriving after the icon surface is detached.  */
   if (!surface)
     return;
 
+  last_drawn_time = XLFrameClockGetFrameTime (clock);
+
+  if (!last_drawn_time)
+    {
       clock_gettime (CLOCK_MONOTONIC, &time);
       XLSurfaceRunFrameCallbacks (surface, time);
+    }
+  else
+    XLSurfaceRunFrameCallbacksMs (surface, last_drawn_time / 1000);
 }
 
 static void
@@ -246,7 +259,7 @@ AfterFrame (FrameClock *clock, void *data)
       return;
     }
 
-  RunFrameCallbacks (icon->role.surface);
+  RunFrameCallbacks (icon->role.surface, clock);
 }
 
 static void
@@ -410,7 +423,11 @@ XLGetIconSurface (Surface *surface)
 		   (unsigned char *) &_NET_WM_WINDOW_TYPE_DND, 1);
 
   /* Create a target associated with the window.  */
-  role->target = RenderTargetFromWindow (role->window);
+  role->target = RenderTargetFromWindow (role->window, None);
+
+  /* For simplicity reasons we do not handle idle notifications
+     asynchronously.  */
+  RenderSetNeedWaitForIdle (role->target);
 
   /* Create a subcompositor associated with the window.  */
   role->subcompositor = MakeSubcompositor ();

output.c

@@ -98,6 +98,9 @@ static ScaleChangeCallback scale_callbacks;
 /* The scale factor currently applied on a global basis.  */
 int global_scale_factor;
 
+/* Function run upon any kind of XRandR notify event.  */
+static void (*change_hook) (Time);
+
 static Bool
 ApplyEnvironment (const char *name, int *variable)
 {
@@ -903,9 +906,38 @@ XLGetOutputRectAt (int x, int y, int *x_out, int *y_out,
 Bool
 XLHandleOneXEventForOutputs (XEvent *event)
 {
+  XRRNotifyEvent *notify;
+  XRROutputPropertyNotifyEvent *property;
+  XRRResourceChangeNotifyEvent *resource;
+  Time time;
+
+  notify = (XRRNotifyEvent *) event;
+
   if (event->type == compositor.rr_event_base + RRNotify)
     {
       NoticeOutputsMaybeChanged ();
+
+      if (change_hook)
+	{
+	  time = CurrentTime;
+
+	  /* See if a timestamp of some sort can be extracted.  */
+	  switch (notify->subtype)
+	    {
+	    case RRNotify_OutputProperty:
+	      property = (XRROutputPropertyNotifyEvent *) notify;
+	      time = property->timestamp;
+	      break;
+
+	    case RRNotify_ResourceChange:
+	      resource = (XRRResourceChangeNotifyEvent *) notify;
+	      time = resource->timestamp;
+	      break;
+	    }
+
+	  change_hook (time);
+	}
+
       return True;
     }
 
@@ -1053,6 +1085,12 @@ XLClearOutputs (Surface *surface)
   surface->n_outputs = 0;
 }
 
+void
+XLOutputSetChangeFunction (void (*change_func) (Time))
+{
+  change_hook = change_func;
+}
+
 void
 XLInitRROutputs (void)
 {
@@ -1096,6 +1134,16 @@ XLInitRROutputs (void)
   scale_callbacks.next = &scale_callbacks;
   scale_callbacks.last = &scale_callbacks;
 
+  if (compositor.rr_major > 1
+      && (compositor.rr_major == 1
+	  && compositor.rr_minor >= 4))
+    XRRSelectInput (compositor.display,
+		    DefaultRootWindow (compositor.display),
+		    (RRCrtcChangeNotifyMask
+		     | RROutputChangeNotifyMask
+		     | RROutputPropertyNotifyMask
+		     | RRResourceChangeNotifyMask));
+  else
     XRRSelectInput (compositor.display,
 		    DefaultRootWindow (compositor.display),
 		    (RRCrtcChangeNotifyMask

renderer.c

@@ -69,9 +69,9 @@ AllocateRenderer (void)
 }
 
 RenderTarget
-RenderTargetFromWindow (Window window)
+RenderTargetFromWindow (Window window, unsigned long standard_event_mask)
 {
-  return render_funcs.target_from_window (window);
+  return render_funcs.target_from_window (window, standard_event_mask);
 }
 
 RenderTarget
@@ -80,6 +80,13 @@ RenderTargetFromPixmap (Pixmap pixmap)
   return render_funcs.target_from_pixmap (pixmap);
 }
 
+void
+RenderSetStandardEventMask (RenderTarget target,
+			    unsigned long standard_event_mask)
+{
+  render_funcs.set_standard_event_mask (target, standard_event_mask);
+}
+
 void
 RenderNoteTargetSize (RenderTarget target, int width, int height)
 {
@@ -177,6 +184,37 @@ RenderGetFinishFence (Bool *error)
   return render_funcs.get_finish_fence (error);
 }
 
+PresentCompletionKey
+RenderPresentToWindow (RenderTarget target, RenderBuffer source,
+		       pixman_region32_t *damage,
+		       PresentCompletionFunc callback, void *data)
+{
+  if (!render_funcs.present_to_window)
+    return NULL;
+
+  return render_funcs.present_to_window (target, source,
+					 damage, callback,
+					 data);
+}
+
+void
+RenderCancelPresentationCallback (PresentCompletionKey key)
+{
+  if (!render_funcs.cancel_presentation_callback)
+    return;
+
+  render_funcs.cancel_presentation_callback (key);
+}
+
+void
+RenderCancelPresentation (RenderTarget target)
+{
+  if (!render_funcs.cancel_presentation)
+    return;
+
+  render_funcs.cancel_presentation (target);
+}
+
 DrmFormat *
 RenderGetDrmFormats (int *n_formats)
 {
@@ -269,6 +307,43 @@ RenderCanReleaseNow (RenderBuffer buffer)
   return buffer_funcs.can_release_now (buffer);
 }
 
+IdleCallbackKey
+RenderAddIdleCallback (RenderBuffer buffer, RenderTarget target,
+		       BufferIdleFunc function, void *data)
+{
+  return buffer_funcs.add_idle_callback (buffer, target, function, data);
+}
+
+void
+RenderCancelIdleCallback (IdleCallbackKey key)
+{
+  return buffer_funcs.cancel_idle_callback (key);
+}
+
+Bool
+RenderIsBufferIdle (RenderBuffer buffer, RenderTarget target)
+{
+  return buffer_funcs.is_buffer_idle (buffer, target);
+}
+
+void
+RenderWaitForIdle (RenderBuffer buffer, RenderTarget target)
+{
+  if (!buffer_funcs.wait_for_idle)
+    return;
+
+  buffer_funcs.wait_for_idle (buffer, target);
+}
+
+void
+RenderSetNeedWaitForIdle (RenderTarget target)
+{
+  if (!buffer_funcs.set_need_wait_for_idle)
+    return;
+
+  buffer_funcs.set_need_wait_for_idle (target);
+}
+
 void
 RegisterStaticRenderer (const char *name,
 			RenderFuncs *render_funcs,

run.c

@@ -139,6 +139,9 @@ HandleOneXEvent (XEvent *event)
   if (XLHandleXEventForXdgSurfaces (event))
     return;
 
+  if (HandleOneXEventForPictureRenderer (event))
+    return;
+
   if (XLHandleXEventForXdgToplevels (event))
     return;
 
@@ -156,9 +159,6 @@ HandleOneXEvent (XEvent *event)
     return;
 #endif
 
-  if (HandleOneXEventForPictureRenderer (event))
-    return;
-
   if (XLHandleOneXEventForXData (event))
     return;
 

seat.c

@@ -711,6 +711,10 @@ MaybeCreateCursor (CursorRing *ring, int index)
 		     compositor.n_planes);
   ring->targets[index]
     = RenderTargetFromPixmap (ring->pixmaps[index]);
+
+  /* For simplicity reasons we do not handle idle notifications
+     asynchronously.  */
+  RenderSetNeedWaitForIdle (ring->targets[index]);
 }
 
 static int
@@ -1208,9 +1212,20 @@ Setup (Surface *surface, Role *role)
 static void
 ReleaseBuffer (Surface *surface, Role *role, ExtBuffer *buffer)
 {
+  SeatCursor *cursor;
+  int i;
+
+  cursor = CursorFromRole (role);
+
   /* Cursors are generally committed only once, so syncing here is
      OK in terms of efficiency.  */
-  XSync (compositor.display, False);
+  for (i = 0; i < CursorRingElements; ++i)
+    {
+      if (cursor->cursor_ring->pixmaps[i])
+	RenderWaitForIdle (XLRenderBufferFromBuffer (buffer),
+			   cursor->cursor_ring->targets[i]);
+    }
+
   XLReleaseBuffer (buffer);
 }
 

subcompositor.c

@@ -310,9 +310,6 @@ struct _View
 
 struct _Subcompositor
 {
-  /* Various flags describing the state of this subcompositor.  */
-  int state;
-
   /* List of all inferiors in compositing order.  */
   List *inferiors, *last;
 
@@ -334,9 +331,29 @@ struct _Subcompositor
   /* Function called with the bounds before each update.  */
   void (*note_bounds) (void *, int, int, int, int);
 
+  /* Function called with the frame counter on each update.  */
+  void (*note_frame) (FrameMode, uint64_t, void *);
+
+  /* The current frame counter, incremented with each frame.  */
+  uint64_t frame_counter;
+
   /* Data for those three functions.  */
   void *opaque_change_data, *input_change_data, *note_bounds_data;
 
+  /* Data for the fourth.  */
+  void *note_frame_data;
+
+  /* Buffers used to store that damage.  */
+  pixman_region32_t prior_damage[2];
+
+  /* The damage region of previous updates.  last_damage is what the
+     damage region was 1 update ago, and before_damage is what the
+     damage region was 2 updates ago.  */
+  pixman_region32_t *last_damage, *before_damage;
+
+  /* The last attached presentation callback, if any.  */
+  PresentCompletionKey present_key;
+
   /* The minimum origin of any surface in this subcompositor.  Used to
      compute the actual size of the subcompositor.  */
   int min_x, min_y;
@@ -347,15 +364,10 @@ struct _Subcompositor
 
   /* An additional offset to apply when drawing to the target.  */
   int tx, ty;
-
-  /* Buffers used to store that damage.  */
-  pixman_region32_t prior_damage[2];
-
-  /* The damage region of previous updates.  last_damage is what the
-     damage region was 1 update ago, and before_damage is what the
-     damage region was 2 updates ago.  */
-  pixman_region32_t *last_damage, *before_damage;
 #endif
+
+  /* Various flags describing the state of this subcompositor.  */
+  int state;
 };
 
 #ifndef TEST
@@ -1807,6 +1819,16 @@ SubcompositorSetBoundsCallback (Subcompositor *subcompositor,
   subcompositor->note_bounds_data = data;
 }
 
+void
+SubcompositorSetNoteFrameCallback (Subcompositor *subcompositor,
+				   void (*note_frame) (FrameMode, uint64_t,
+						       void *),
+				   void *data)
+{
+  subcompositor->note_frame = note_frame;
+  subcompositor->note_frame_data = data;
+}
+
 static void
 FillBoxesWithTransparency (Subcompositor *subcompositor,
 			   pixman_box32_t *boxes, int nboxes)
@@ -1917,6 +1939,69 @@ IntersectBoxes (pixman_box32_t *in, pixman_box32_t *other,
   return True;
 }
 
+static Bool
+NoViewsAfter (View *first_view)
+{
+  List *list;
+  View *view;
+
+  list = first_view->link->next;
+
+  while (list != first_view->link)
+    {
+      view = list->view;
+
+      if (!view)
+	goto next_1;
+
+      if (IsViewUnmapped (view))
+	{
+	  /* Skip the unmapped view.  */
+	  list = view->inferior;
+	  goto next_1;
+	}
+
+      if (IsSkipped (view))
+	{
+	  /* We must skip this view, as it represents (for
+	     instance) a subsurface that has been added, but not
+	     committed.  */
+	  goto next_1;
+	}
+
+      if (!view->buffer)
+	goto next_1;
+
+      /* There is view in front of view that potentially obscures it.
+	 Bail out! */
+      return False;
+
+    next_1:
+      list = list->next;
+    }
+
+  return True;
+}
+
+static void
+PresentCompletedCallback (void *data)
+{
+  Subcompositor *subcompositor;
+
+  subcompositor = data;
+
+  /* The presentation callback should still be set here.  */
+  XLAssert (subcompositor->present_key != NULL);
+
+  subcompositor->present_key = NULL;
+
+  /* Call the presentation callback if it is still set.  */
+  if (subcompositor->note_frame)
+    subcompositor->note_frame (ModePresented,
+			       subcompositor->frame_counter,
+			       subcompositor->note_frame_data);
+}
+
 void
 SubcompositorUpdate (Subcompositor *subcompositor)
 {
@@ -1928,9 +2013,10 @@ SubcompositorUpdate (Subcompositor *subcompositor)
   int nboxes, i, tx, ty, view_width, view_height;
   Operation op;
   RenderBuffer buffer;
-  int min_x, min_y;
+  int min_x, min_y, age, n_seen;
-  int age;
   DrawParams draw_params;
+  Bool presented;
+  PresentCompletionKey key;
 
   /* Just return if no target was specified.  */
   if (!IsTargetAttached (subcompositor))
@@ -1940,6 +2026,13 @@ SubcompositorUpdate (Subcompositor *subcompositor)
   if (IsFrozen (subcompositor))
     return;
 
+  if (subcompositor->present_key)
+    /* Cancel the presentation callback.  The next presentation will
+       either be to an unmapped window, cancel the presentation, or
+       start a new one.  */
+    RenderCancelPresentationCallback (subcompositor->present_key);
+  subcompositor->present_key = NULL;
+
   list = subcompositor->inferiors;
   min_x = subcompositor->min_x;
   min_y = subcompositor->min_y;
@@ -1949,6 +2042,8 @@ SubcompositorUpdate (Subcompositor *subcompositor)
   original_start = NULL;
   pixman_region32_init (&temp);
   pixman_region32_init (&update_region);
+  n_seen = 0;
+  presented = False;
 
   start = subcompositor->inferiors->next->view;
   original_start = subcompositor->inferiors->next->view;
@@ -2042,6 +2137,9 @@ SubcompositorUpdate (Subcompositor *subcompositor)
 	  if (!view->buffer)
 	    goto next;
 
+	  /* Increase the number of views seen count.  */
+	  n_seen++;
+
 	  /* Obtain the view width and height here.  */
 	  view_width = ViewWidth (view);
 	  view_height = ViewHeight (view);
@@ -2265,8 +2363,16 @@ SubcompositorUpdate (Subcompositor *subcompositor)
   /* If there's nothing to do, return.  */
 
   if (!start)
+    /* There is no starting view.  Presentation is not cancelled in
+       this case, because the surface should now be unmapped.  */
     goto complete;
 
+  /* Increase the frame count and announce the new frame number.  */
+  if (subcompositor->note_frame)
+    subcompositor->note_frame (ModeStarted,
+			       ++subcompositor->frame_counter,
+			       subcompositor->note_frame_data);
+
   /* Now update all views from start onwards.  */
 
   list = start->link;
@@ -2311,6 +2417,7 @@ SubcompositorUpdate (Subcompositor *subcompositor)
       view_width = ViewWidth (view);
       view_height = ViewHeight (view);
 
+      /* And the buffer.  */
       buffer = XLRenderBufferFromBuffer (view->buffer);
 
       if (IsGarbaged (subcompositor))
@@ -2337,8 +2444,67 @@ SubcompositorUpdate (Subcompositor *subcompositor)
 				       &draw_params);
 	}
 
+      /* Compute the transform and put it in draw_params.  */
+      ViewComputeTransform (view, &draw_params, True);
+
       if (!first)
 	{
+	  /* See if the first mapped and visible view after start is eligible
+	     for direct presentation.  It is considered eligible if:
+
+	     - its bounds match that of the subcompositor.
+	     - its depth and masks match that of the subcompositor.
+	     - it is not occluded by any other view, above or below.
+	     - it has no transform whatsoever.
+
+	     Also, presentation is done asynchronously, so we only
+	     consider the view as eligible for presentation if
+	     completion callbacks are attached.  */
+
+	  if (!draw_params.flags
+	      && view->abs_x == subcompositor->min_x
+	      && view->abs_y == subcompositor->min_y
+	      && view_width == SubcompositorWidth (subcompositor)
+	      && view_height == SubcompositorHeight (subcompositor)
+	      /* N.B. that n_seen is not set (0) if the view is
+		 garbaged.  */
+	      && (n_seen == 1 || (!n_seen && NoViewsAfter (view)))
+	      && subcompositor->note_frame)
+	    {
+	      /* Direct presentation is okay.  Present the pixmap to
+		 the drawable.  */
+	      if (IsGarbaged (subcompositor))
+		key = RenderPresentToWindow (subcompositor->target, buffer,
+					     NULL, PresentCompletedCallback,
+					     subcompositor);
+	      else
+		key = RenderPresentToWindow (subcompositor->target, buffer,
+					     &update_region,
+					     PresentCompletedCallback,
+					     subcompositor);
+
+	      /* Now set presented to whether or not key is non-NULL.  */
+	      presented = key != NULL;
+
+	      /* And set the presentation callback.  */
+	      subcompositor->present_key = key;
+
+	      if (presented)
+		{
+		  /* If presentation succeeded, don't composite.
+		     Instead, just continue looping to set the input
+		     region if garbaged.  */
+
+		  if (!IsGarbaged (subcompositor) && (age >= 0 && age < 3))
+		    /* And if not garbaged, skip everything.  */
+		    goto present_success;
+		  else
+		    goto present_success_garbaged;
+		}
+	    }
+	  else
+	    RenderCancelPresentation (subcompositor->target);
+
 	  /* The first view with an attached buffer should be drawn
 	     with PictOpSrc so that transparency is applied correctly,
 	     if it contains the entire update region.  */
@@ -2388,10 +2554,11 @@ SubcompositorUpdate (Subcompositor *subcompositor)
       else
 	op = OperationOver;
 
-      first = view;
+      if (presented && (IsGarbaged (subcompositor)
+			|| age < 0 || age >= 3))
+	goto present_success_garbaged;
 
-      /* Compute the transform and put it in draw_params.  */
+      first = view;
-      ViewComputeTransform (view, &draw_params, True);
 
       if (!IsGarbaged (subcompositor) && (age >= 0 && age < 3))
 	{
@@ -2428,11 +2595,6 @@ SubcompositorUpdate (Subcompositor *subcompositor)
 	}
       else
 	{
-	  /* Clear the damaged area, since it will either be drawn or
-	     be obscured.  We didn't get a chance to clear the damage
-	     earlier, since the compositor was garbaged.  */
-	  pixman_region32_clear (&view->damage);
-
 	  /* If the subcompositor is garbaged, composite the entire
 	     view to the right location.  */
 	  RenderComposite (buffer, subcompositor->target, op,
@@ -2447,6 +2609,12 @@ SubcompositorUpdate (Subcompositor *subcompositor)
 			   /* height, draw-params.  */
 			   view_height, &draw_params);
 
+	present_success_garbaged:
+	  /* Clear the damaged area, since it will either be drawn or
+	     be obscured.  We didn't get a chance to clear the damage
+	     earlier, since the compositor was garbaged.  */
+	  pixman_region32_clear (&view->damage);
+
 	  /* Also adjust the opaque and input regions here.  */
 
 	  if (pixman_region32_not_empty (&view->opaque)
@@ -2501,6 +2669,8 @@ SubcompositorUpdate (Subcompositor *subcompositor)
     }
   while (list != subcompositor->inferiors);
 
+ present_success:
+
   /* Swap changes to display.  */
 
   if (IsGarbaged (subcompositor) || age < 0 || age >= 3)
@@ -2561,6 +2731,12 @@ SubcompositorUpdate (Subcompositor *subcompositor)
   subcompositor->state &= ~SubcompositorIsGarbaged;
   subcompositor->state &= ~SubcompositorIsOpaqueDirty;
   subcompositor->state &= ~SubcompositorIsInputDirty;
+
+  /* Call the frame complete function if presentation did not happen.  */
+  if (subcompositor->note_frame && !presented)
+    subcompositor->note_frame (ModeComplete,
+			       subcompositor->frame_counter,
+			       subcompositor->note_frame_data);
 }
 
 void
@@ -2735,6 +2911,10 @@ SubcompositorFree (Subcompositor *subcompositor)
   pixman_region32_fini (&subcompositor->prior_damage[0]);
   pixman_region32_fini (&subcompositor->prior_damage[1]);
 
+  /* Remove the presentation key.  */
+  if (subcompositor->present_key)
+    RenderCancelPresentationCallback (subcompositor->present_key);
+
   XLFree (subcompositor);
 }
 

surface.c

@@ -1599,6 +1599,19 @@ XLSurfaceRunFrameCallbacks (Surface *surface, struct timespec time)
     XLSurfaceRunFrameCallbacks (list->data, time);
 }
 
+void
+XLSurfaceRunFrameCallbacksMs (Surface *surface, uint32_t ms_time)
+{
+  XLList *list;
+
+  RunFrameCallbacks (&surface->current_state.frame_callbacks,
+		     ms_time);
+
+  /* Run frame callbacks for each attached subsurface as well.  */
+  for (list = surface->subsurfaces; list; list = list->next)
+    XLSurfaceRunFrameCallbacksMs (list->data, ms_time);
+}
+
 CommitCallback *
 XLSurfaceRunAtCommit (Surface *surface,
 		      void (*commit_func) (Surface *, void *),

text_input.c

@@ -72,7 +72,7 @@ along with 12to11.  If not, see <https://www.gnu.org/licenses/>.  */
    That means it is impossible to attribute forwarded events or
    committed text to the correct XIC, and thus it is impossible to
    look up which seat's TextInput resource an event is actually bound
-   for.  If one day we move to our own implementation of the XIC
+   for.  If one day we move to our own implementation of the XIM
    protocol, then it will become possible to properly support
    multi-seat setups, with one XIC per-client and per-seat.
 
@@ -86,7 +86,7 @@ along with 12to11.  If not, see <https://www.gnu.org/licenses/>.  */
    converted string before being sent to the client.
 
    This code has many inherent race conditions, just like the
-   zwp_text_input_v3 protocol itself.  As described above, it only
+   zwp_text_input_v3 protocol itself.  And as described above, it only
    supports one seat due to limitations of the Xlib XIM wrapper.  */
 
 typedef struct _TextInputClientInfo TextInputClientInfo;

xdg-shell.xml

@@ -454,6 +454,7 @@
       <entry name="not_constructed" value="1"/>
       <entry name="already_constructed" value="2"/>
       <entry name="unconfigured_buffer" value="3"/>
+      <entry name="invalid_serial" value="4"/>
     </enum>
 
     <request name="destroy" type="destructor">
@@ -549,6 +550,17 @@
 	A client may send multiple ack_configure requests before committing, but
 	only the last request sent before a commit indicates which configure
 	event the client really is responding to.
+
+	Sending an ack_configure request consumes the serial number sent with
+	the request, as well as serial numbers sent by all configure events
+	sent on this xdg_surface prior to the configure event referenced by
+	the committed serial.
+
+	It is an error to issue multiple ack_configure requests referencing a
+	serial from the same configure event, or to issue an ack_configure
+	request referencing a serial from a configure event issued before the
+	event identified by the last ack_configure request for the same
+	xdg_surface. Doing so will raise an invalid_serial error.
       </description>
       <arg name="serial" type="uint" summary="the serial from the configure event"/>
     </request>

xdg_surface.c

@@ -44,6 +44,7 @@ enum
     StateMaybeConfigure		= (1 << 6),
     StateDirtyFrameExtents	= (1 << 7),
     StateTemporaryBounds	= (1 << 8),
+    StateFrameStarted		= (1 << 9),
   };
 
 typedef struct _XdgRole XdgRole;
@@ -106,6 +107,9 @@ struct _XdgRole
   /* The implementation of this role.  */
   XdgRoleImplementation *impl;
 
+  /* The pending frame ID.  */
+  uint64_t pending_frame;
+
   /* Various role state.  */
   int state;
 
@@ -123,7 +127,7 @@ struct _XdgRole
   XdgState current_state;
 
   /* Configure event serial.  */
-  uint32_t conf_serial;
+  uint32_t conf_serial, last_specified_serial;
 
   /* The current bounds of the subcompositor.  */
   int min_x, min_y, max_x, max_y;
@@ -156,13 +160,16 @@ struct _ReleaseLaterRecord
   /* A monotonically (overflow aside) increasing identifier.  */
   uint64_t id;
 
-  /* Key for the free func.  */
-  void *free_func_key;
-
   /* The buffer that should be released upon receiving this
      message.  */
   ExtBuffer *buffer;
 
+  /* The idle callback.  */
+  IdleCallbackKey key;
+
+  /* The XdgRole.  */
+  XdgRole *role;
+
   /* The next and last records.  */
   ReleaseLaterRecord *next, *last;
 };
@@ -170,24 +177,6 @@ struct _ReleaseLaterRecord
 /* Event base of the XShape extension.  */
 int shape_base;
 
-static void
-RemoveRecord (ReleaseLaterRecord *record)
-{
-  /* Removing the sentinel record is invalid.  */
-  XLAssert (record->buffer != NULL);
-
-  /* First, make the rest of the list skip RECORD.  */
-  record->last->next = record->next;
-  record->next->last = record->last;
-
-  /* Next, remove the buffer listener.  */
-  XLBufferCancelRunOnFree (record->buffer,
-			   record->free_func_key);
-
-  /* Finally, free RECORD.  */
-  XLFree (record);
-}
-
 static void
 DeleteRecord (ReleaseLaterRecord *record)
 {
@@ -217,10 +206,6 @@ FreeRecords (ReleaseLaterRecord *records)
       /* Release the buffer now.  */
       XLReleaseBuffer (last->buffer);
 
-      /* And cancel the destroy listener.  */
-      XLBufferCancelRunOnFree (last->buffer,
-			       last->free_func_key);
-
       /* Before freeing the record itself.  */
       XLFree (last);
     }
@@ -311,24 +296,26 @@ FreeReconstrainCallbacks (XdgRole *role)
     }
 }
 
-static void
-ReleaseLaterExtBufferFunc (ExtBuffer *buffer, void *data)
-{
-  DeleteRecord (data);
-}
-
 static void
 RunFrameCallbacks (Surface *surface, XdgRole *role)
 {
   struct timespec time;
+  uint64_t last_drawn_time;
 
   /* Surface can be NULL for various reasons, especially events
      arriving after the shell surface is detached.  */
   if (!surface)
     return;
 
+  last_drawn_time = XLFrameClockGetFrameTime (role->clock);
+
+  if (!last_drawn_time)
+    {
       clock_gettime (CLOCK_MONOTONIC, &time);
       XLSurfaceRunFrameCallbacks (surface, time);
+    }
+  else
+    XLSurfaceRunFrameCallbacksMs (surface, last_drawn_time / 1000);
 }
 
 static void
@@ -344,25 +331,18 @@ RunFrameCallbacksConditionally (XdgRole *role)
 }
 
 static void
-HandleReleaseLaterMessage (XdgRole *role, uint64_t id)
+BufferIdleCallback (RenderBuffer buffer, void *data)
 {
   ReleaseLaterRecord *record;
+  XdgRole *role;
   Surface *surface;
 
-  record = role->release_records->last;
+  record = data;
+  role = record->role;
 
-  if (record == role->release_records)
-    return;
 
-  /* Since the list of release records is a (circular) queue, ID will
-     either be the last element or invalid as the buffer has been
-     destroyed.  */
-
-  if (record->id == id)
-    {
   XLReleaseBuffer (record->buffer);
-      RemoveRecord (record);
+  DeleteRecord (record);
-    }
 
   surface = role->role.surface;
 
@@ -377,70 +357,12 @@ HandleReleaseLaterMessage (XdgRole *role, uint64_t id)
     }
 }
 
-/* It shouldn't be possible for billions of frames to pile up without
-   a response from the X server, so relying on wraparound to handle id
-   overflow should be fine.  */
-
-static void
-ReleaseLater (XdgRole *role, ExtBuffer *buffer)
-{
-  ReleaseLaterRecord *record;
-  XEvent event;
-  static uint64_t id;
-
-  /* Send a message to the X server; once it is received, release the
-     given buffer.  This is necessary because the connection to the X
-     server does not behave synchronously, and receiving the message
-     tells us that the X server has finished processing all requests
-     that access the buffer.  */
-
-  record = AddRecordAfter (role->release_records);
-  record->id = ++id;
-  record->buffer = buffer;
-  record->free_func_key
-    = XLBufferRunOnFree (buffer, ReleaseLaterExtBufferFunc,
-			 record);
-
-  memset (&event, 0, sizeof event);
-
-  event.xclient.type = ClientMessage;
-  event.xclient.window = role->window;
-  event.xclient.message_type = _XL_BUFFER_RELEASE;
-  event.xclient.format = 32;
-
-  event.xclient.data.l[0] = id >> 31 >> 1;
-  event.xclient.data.l[1] = id & 0xffffffff;
-
-  XSendEvent (compositor.display, role->window, False,
-	      NoEventMask, &event);
-}
-
 Bool
 XLHandleXEventForXdgSurfaces (XEvent *event)
 {
   XdgRole *role;
-  uint64_t id, low, high;
   Window window;
 
-  if (event->type == ClientMessage
-      && event->xclient.message_type == _XL_BUFFER_RELEASE)
-    {
-      role = XLLookUpAssoc (surfaces, event->xclient.window);
-
-      if (role)
-	{
-	  /* These values are masked because Xlib sign-extends 32-bit
-	     values to fit potentially 64-bit long.  */
-	  low = event->xclient.data.l[0] & 0xffffffff;
-	  high = event->xclient.data.l[1] & 0xffffffff;
-
-	  id = (low << 32) | high;
-	  HandleReleaseLaterMessage (role, id);
-	}
-
-      return True;
-    }
-
   if (event->type == ClientMessage
       && ((event->xclient.message_type == _NET_WM_FRAME_DRAWN
 	   || event->xclient.message_type == _NET_WM_FRAME_TIMINGS)
@@ -611,8 +533,29 @@ AckConfigure (struct wl_client *client, struct wl_resource *resource,
   if (!xdg_role->role.surface)
     return;
 
+#ifdef DEBUG_GEOMETRY_CALCULATION
+  fprintf (stderr, "ack_configure: %"PRIu32"\n", serial);
+#endif
+
+  if (serial < xdg_role->conf_serial)
+    {
+      /* The client specified an outdated serial.  */
+      wl_resource_post_error (resource, XDG_SURFACE_ERROR_INVALID_SERIAL,
+			      "serial specified not monotonic");
+      return;
+    }
+
+  if (serial && serial == xdg_role->last_specified_serial)
+    {
+      /* The client specified the same serial twice.  */
+      wl_resource_post_error (resource, XDG_SURFACE_ERROR_INVALID_SERIAL,
+			      "same serial specified twice");
+      return;
+    }
+
   if (serial == xdg_role->conf_serial)
     {
+      xdg_role->last_specified_serial = serial;
       xdg_role->state &= ~StateWaitingForAckConfigure;
 
       /* Garbage the subcompositor too, since contents could be
@@ -720,6 +663,12 @@ Commit (Surface *surface, Role *role)
   if (!IsRoleMapped (xdg_role))
     goto start_drawing;
 
+  /* If the frame clock is frozen but we are no longer waiting for the
+     configure event to be acknowledged by the client, unfreeze the
+     frame clock.  */
+  if (!(xdg_role->state & StateWaitingForAckConfigure))
+    Unfreeze (xdg_role);
+
   /* A frame is already in progress, so instead say that an urgent
      update is needed immediately after the frame completes.  In any
      case, don't run frame callbacks upon buffer release anymore.  */
@@ -727,8 +676,9 @@ Commit (Surface *surface, Role *role)
     {
       if (XLFrameClockCanBatch (xdg_role->clock))
 	/* But if we can squeeze the frame inside the vertical
-	   blanking period, go ahead.  */
+	   blanking period, or a frame is in progress but EndFrame has
-	goto just_draw_then_return;
+	   not yet been called, go ahead.  */
+	goto start_drawing;
 
       xdg_role->state |= StateLateFrame;
       xdg_role->state &= ~StatePendingFrameCallback;
@@ -743,38 +693,12 @@ Commit (Surface *surface, Role *role)
 
  start_drawing:
 
-  /* If the frame clock is frozen but we are no longer waiting for the
-     configure event to be acknowledged by the client, unfreeze the
-     frame clock.  */
-  if (!(xdg_role->state & StateWaitingForAckConfigure))
-    Unfreeze (xdg_role);
-
-  XLFrameClockStartFrame (xdg_role->clock, False);
   SubcompositorUpdate (xdg_role->subcompositor);
 
-  /* Also run role "commit inside frame" hook.  */
+  /* Do not end frames explicitly.  Instead, wait for the
-  if (xdg_role->impl && xdg_role->impl->funcs.commit_inside_frame)
+     NoteFrameCallback to end the frame.  */
-    xdg_role->impl->funcs.commit_inside_frame (role, xdg_role->impl);
-  XLFrameClockEndFrame (xdg_role->clock);
-
-  /* Clients which commit when a configure event that has not yet been
-     acked still expect frame callbacks to be called; however, frame
-     callbacks are not provided by the frame clock while it is frozen.
-
-     If that happens, just run the frame callback immediately.  */
-  if (XLFrameClockIsFrozen (xdg_role->clock)
-      /* If the window is not mapped, then the native frame clock will
-	 not draw frames.  Some clients do commit before the initial
-	 configure event and wait for the frame callback to be called
-	 after or before ack_configure, leading to the mapping commit
-	 never being performed.  */
-      || !IsRoleMapped (xdg_role))
-    RunFrameCallbacksConditionally (xdg_role);
 
   return;
-
- just_draw_then_return:
-  SubcompositorUpdate (xdg_role->subcompositor);
 }
 
 static Bool
@@ -887,7 +811,27 @@ Teardown (Surface *surface, Role *role)
 static void
 ReleaseBuffer (Surface *surface, Role *role, ExtBuffer *buffer)
 {
-  ReleaseLater (XdgRoleFromRole (role), buffer);
+  RenderBuffer render_buffer;
+  ReleaseLaterRecord *record;
+  XdgRole *xdg_role;
+
+  render_buffer = XLRenderBufferFromBuffer (buffer);
+  xdg_role = XdgRoleFromRole (role);
+
+  if (RenderIsBufferIdle (render_buffer, xdg_role->target))
+    /* If the buffer is already idle, release it now.  */
+    XLReleaseBuffer (buffer);
+  else
+    {
+      /* Release the buffer once it is destroyed or becomes idle.  */
+      record = AddRecordAfter (xdg_role->release_records);
+      record->buffer = buffer;
+      record->key = RenderAddIdleCallback (render_buffer,
+					   xdg_role->target,
+					   BufferIdleCallback,
+					   record);
+      record->role = xdg_role;
+    }
 }
 
 static Bool
@@ -915,7 +859,8 @@ Subframe (Surface *surface, Role *role)
     {
       if (XLFrameClockCanBatch (xdg_role->clock))
 	/* But if we can squeeze the frame inside the vertical
-	   blanking period, go ahead.  */
+	   blanking period, or a frame is in progress but EndFrame has
+	   not yet been called, go ahead.  */
 	return True;
 
       xdg_role->state |= StateLateFrame;
@@ -927,18 +872,14 @@ Subframe (Surface *surface, Role *role)
       return False;
     }
 
-  /* I guess subsurface updates don't count as urgent frames?  */
-  XLFrameClockStartFrame (xdg_role->clock, False);
   return True;
 }
 
 static void
 EndSubframe (Surface *surface, Role *role)
 {
-  XdgRole *xdg_role;
+  /* Don't end the frame here; instead, wait for the frame callback to
-
+     note that drawing the frame has finished.  */
-  xdg_role = XdgRoleFromRole (role);
-  XLFrameClockEndFrame (xdg_role->clock);
 }
 
 static Window
@@ -969,34 +910,6 @@ AfterFrame (FrameClock *clock, void *data)
 
   role = data;
 
-  if (role->state & StateLateFrame)
-    {
-      role->state &= ~StateLateFrame;
-
-      if (role->state & StateLateFrameAcked)
-	XLFrameClockUnfreeze (role->clock);
-
-      /* Since we are running late, make the compositor draw the frame
-	 now.  */
-      XLFrameClockStartFrame (clock, True);
-      SubcompositorUpdate (role->subcompositor);
-
-      /* Also run role "commit inside frame" hook.  */
-      if (role->impl
-	  && role->impl->funcs.commit_inside_frame)
-	role->impl->funcs.commit_inside_frame (&role->role,
-					       role->impl);
-      XLFrameClockEndFrame (clock);
-
-      /* See the comment in Commit about frame callbacks being
-	 attached while the frame clock is frozen.  */
-      if (XLFrameClockIsFrozen (role->clock)
-	  && role->role.surface)
-	RunFrameCallbacksConditionally (role);
-
-      return;
-    }
-
   /* If all pending frames have been drawn, run frame callbacks.
      Unless some buffers have not yet been released, in which case the
      callbacks will be run when they are.  */
@@ -1234,6 +1147,63 @@ NoteBounds (void *data, int min_x, int min_y,
     RunReconstrainCallbacks (role);
 }
 
+static void
+NoteFrame (FrameMode mode, uint64_t id, void *data)
+{
+  XdgRole *role;
+
+  role = data;
+
+  switch (mode)
+    {
+    case ModeStarted:
+      /* Record this frame counter as the pending frame.  */
+      role->pending_frame = id;
+
+      if (!(role->state & StateFrameStarted))
+	{
+	  role->state |= StateFrameStarted;
+	  XLFrameClockStartFrame (role->clock, False);
+	}
+
+      /* Also run role "commit inside frame" hook.  */
+      if (role->impl && role->impl->funcs.commit_inside_frame)
+	role->impl->funcs.commit_inside_frame (&role->role,
+					       role->impl);
+
+      break;
+
+    case ModePresented:
+    case ModeComplete:
+      /* The frame was completed.  */
+      if (id == role->pending_frame)
+	{
+	  /* End the frame.  */
+	  XLFrameClockEndFrame (role->clock);
+
+	  /* Clear the frame completed flag.  */
+	  role->state &= ~StateFrameStarted;
+
+	  /* Clients which commit when a configure event that has not
+	     yet been acked still expect frame callbacks to be called;
+	     however, frame callbacks are not provided by the frame
+	     clock while it is frozen.
+
+	     If that happens, just run the frame callback
+	     immediately.  */
+	  if (XLFrameClockIsFrozen (role->clock)
+	      /* If the window is not mapped, then the native frame
+		 clock will not draw frames.  Some clients do commit
+		 before the initial configure event and wait for the
+		 frame callback to be called after or before
+		 ack_configure, leading to the mapping commit never
+		 being performed.  */
+	      || !IsRoleMapped (role))
+	    RunFrameCallbacksConditionally (role);
+	}
+    }
+}
+
 static void
 ResizeForMap (XdgRole *role)
 {
@@ -1387,6 +1357,10 @@ SelectExtraEvents (Surface *surface, Role *role,
   /* Select extra events for the input method.  */
   XSelectInput (compositor.display, xdg_role->window,
 		DefaultEventMask | event_mask);
+
+  /* Set the target standard event mask.  */
+  RenderSetStandardEventMask (xdg_role->target,
+			      DefaultEventMask | event_mask);
 }
 
 void
@@ -1482,7 +1456,7 @@ XLGetXdgSurface (struct wl_client *client, struct wl_resource *resource,
 				0, 0, 20, 20, 0, compositor.n_planes,
 				InputOutput, compositor.visual, flags,
 				&attrs);
-  role->target = RenderTargetFromWindow (role->window);
+  role->target = RenderTargetFromWindow (role->window, DefaultEventMask);
 
   role->subcompositor = MakeSubcompositor ();
   role->clock = XLMakeFrameClockForWindow (role->window);
@@ -1496,6 +1470,8 @@ XLGetXdgSurface (struct wl_client *client, struct wl_resource *resource,
 				  OpaqueRegionChanged, role);
   SubcompositorSetBoundsCallback (role->subcompositor,
 				  NoteBounds, role);
+  SubcompositorSetNoteFrameCallback (role->subcompositor,
+				     NoteFrame, role);
   XLSelectStandardEvents (role->window);
   XLMakeAssoc (surfaces, role->window, role);
 
@@ -1581,7 +1557,8 @@ XLXdgRoleSendConfigure (Role *role, uint32_t serial)
   xdg_role->state &= ~StateMaybeConfigure;
 
 #ifdef DEBUG_GEOMETRY_CALCULATION
-  fprintf (stderr, "Waiting for ack_configure...\n");
+  fprintf (stderr, "Waiting for ack_configure (%"PRIu32")...\n",
+	   xdg_role->conf_serial);
 #endif
 
   xdg_surface_send_configure (role->resource, serial);