The stack and stack tracker tend to cause missed frames from time to
time, especially when there are many open windows. Add some
instrumentation to make it this easily verifiable when profiling.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1616>
X11 window stacking operations are by nature prone to race conditions.
For example, we might queue a "raise above" operation, but before it
actually takes place, the sibling the window was to be rased above, is
withdrawn.
In these cases we'd log warnings even though they are expected to
happen. Downgrade these warnings to debug messages, only printed when
MUTTER_VERBOSE is set.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1300
We have a "setup" phase, used internally to initialize early the x11
side of things like the stack tracker, and an "opened" phase where
other upper parts may hook up to. This latter phase is delayed during
initialization so the upper parts have a change to connect to on
plugin creation.
Closes: https://gitlab.gnome.org/GNOME/mutter/issues/771
This object can be generally triggered without a X11 display, so make sure
this is alright. For guard window checks, use our internal
meta_stack_tracker_is_guard_window() call, which is already no-x11 aware.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/730
If the display is closed prematurely, go through all windows that
look X11-y and remove them for future calculations. This is not
strictly needed as Xwayland should shut down orderly (thus no client
windows be there), but doesn't hurt to prepare in advance for the
cases where it might not be the case.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/709
The order and way include macros were structured was chaotic, with no
real common thread between files. Try to tidy up the mess with some
common scheme, to make things look less messy.
As of "stack-tracker: Keep override redirect windows on top"
(e3d5bc077d), we always sorted all
override redirect on top of regular windows, as so is expected by
regular override redirect windows. This had an unwanted consequence,
however, which is that we should still not sort such override redirect
windows on top if they are behind the guard window, as that'd result in
windows hidden behind it now getting restacked anyway.
Fix this by only sorting the override redirect windows that are found
above the guard window on top. This fixes the override-redirect stacking
test.
They are X11 specific functions, used for X11 code. They have been
improved per jadahl's suggestion to use gdk_x11_lookup_xdisplay and
gdk_x11_display_error_trap_* functions, instead of current code.
https://bugzilla.gnome.org/show_bug.cgi?id=759538
- Moved xdisplay, name and various atoms from MetaDisplay
- Moved xroot, screen_name, default_depth and default_xvisual
from MetaScreen
- Moved some X11 specific functions from screen.c and display.c
to meta-x11-display.c
https://bugzilla.gnome.org/show_bug.cgi?id=759538
Since commit 6b5cf2e, we keep override redirect windows on a layer
above regular windows in the clutter actor scene graph. In the X
server, and thus for input purposes, these windows might end up being
stacked below regular windows though, e.g. because a new regular
window is mapped after an OR window.
Fix this disconnect by re-stacking OR windows on top when syncing the
window stack with the compositor.
https://bugzilla.gnome.org/show_bug.cgi?id=780485
Restacking the frame for a window while unmanaging the window is
harmless, but for undecorated (in particular, client-side-decorated)
windows, this causes problems because the window is typically
destroyed by the client immediately after withredrawing the window.
Skip windows flagged as being unmanaged when assembling the new
stack and when comparing the old order to the new stack.
Add a stacking test for this.
When restacking the last window alone, we would trigger this off-by-one
error. This would throw us off the end of the array, causing lower_below
warnings for nonsensical values.
Since the last window already is lowered below everything else, we
shouldn't need to lower it.
We have a quite accurate view of the X stack, so there's no good reason to ask
the X server to do restacking that has no effect. (Restackings that have no
effect on either X windows or Wayland windows were generally optimized out in
the synchronization code, but in other cases like moving an X window that is
only beneath Wayland windows to the top of the stack we would make such
requests.)
Removing such requests:
- Is a small efficiency win in itself
- Allows us to immediately go ahead and apply Wayland changes to the verified stack
- Prevents queued Wayland changes piling up waiting for an X event that will never
be received, since the X server will not send confirmation of no-op restacks.
Since such operations may still have an effect on the relative stacking of X
and Wayland windows, we need to continue applying them to the local stack.
https://bugzilla.gnome.org/show_bug.cgi?id=736559
Now that all actual stack shuffle is handled inside stack-tracker.c, we can make
meta_stack_tracker_record_[raise_above/lower_below] internal to that file and
remove the unused meta_stack_tracker_record_lower().
https://bugzilla.gnome.org/show_bug.cgi?id=736559
stack.c:sync_stack_to_xserver had both code for assembling the desired stack, and
code for enforcing the desired stack on the actual stack of X and Wayland windows;
the latter part is properly the domain of stack-tracker.c; moving the code to
apply the stack there both simplifies it and keeps stack.c more manageable.
https://bugzilla.gnome.org/show_bug.cgi?id=736559
Since MetaStackTracker is the code that knows about the current X stacking order
and the relationship between X windows and Wayland windows, it's cleaner to
encapsulate stack manipulation in MetaStackTracker rather than have the calling
code make the X calls and only call into MetaStackTracker to inform it about
the changes.
https://bugzilla.gnome.org/show_bug.cgi?id=736559
The step where we requery the stacking order from the server than combine
it in an arbitrary fashion with Wayland windows can be eliminated by observing
that we are the final authority for Wayland window stacking - so if we
apply each X event that we receive from the X server to our stack in a
way that leaves the X windows ordered in the same way as on the server,
and apply events that we have stored locally in a way that doesn't affect
the ordering of X windows, than we have a fully correct ordering of windows.
Ordering this in the order of first applying the X event and then applying the
local portion also means that as long as we had an up-to-date view of the X
stack the composite operation will be identical to what was requested.
https://bugzilla.gnome.org/show_bug.cgi?id=736559
Putting X windows and pointers to MetaWindows into a union had a number of
problems:
- It caused awkward initialization and conditionalization
- There was no way to refer to Wayland windows (represented by
MetaWindow *) in the past, which is necessary for the MetaStackTracker
algorithms
- We never even cleaned up old MetaStackWindow so there could be
records in MetaStackWindow pointing to freed MetaWindow.
Replace MetaStackWindow with a 64-bit "stack ID" which is:
- The XID for X Windows
- a "window stamp" for Wayland windows - window stamps are assigned
for all MetaWindow and are unique across the life of the process.
https://bugzilla.gnome.org/show_bug.cgi?id=736559
If we apply a prediction immediately instead of queueing, we should
also free the operation immediately.
If we discard the prediction queue because we resync fully, we
need to free each operation too.
https://bugzilla.gnome.org/show_bug.cgi?id=729732
Compositors haven't been able to manage more than one screen for
quite a while. Merge MetaCompScreen into MetaCompositor, and update
the API to match.
We still keep MetaScreen in the public compositor API for compatibility
purposes.
At one point, it was supported to run mutter without a compositor,
but we don't allow that any longer. A lot of code already assumes
display->compositor exists and doesn't check for a NULL pointer,
so just kill the rest of the checks.
It triggers too often, making G_DEBUG=fatal-warnings quite useless.
Owen is going to rewrite this code sometime in the near future, so
I'm just gonna kill this warning for now.
This breaks down the assumptions in stack-tracker.c and stack.c that
Mutter is only stacking X windows.
The stack tracker now tracks windows using a MetaStackWindow structure
which is a union with a type member so that X windows can be
distinguished from Wayland windows.
Some notable changes are:
Queued stack tracker operations that affect Wayland windows will not be
associated with an X serial number.
If an operation only affects a Wayland window and there are no queued
stack tracker operations ("unvalidated predictions") then the operation
is applied immediately since there is no server involved with changing
the stacking for Wayland windows.
The stack tracker can no longer respond to X events by turning them into
stack operations and discarding the predicted operations made prior to
that event because operations based on X events don't know anything
about the stacking of Wayland windows.
Instead of discarding old predictions the new approach is to trust the
predictions but whenever we receive an event from the server that
affects stacking we cross-reference with the predicted stack and check
for consistency. So e.g. if we have an event that says ADD window A then
we apply the predictions (up to the serial for that event) and verify
the predicted state includes a window A. Similarly if an event says
RAISE_ABOVE(B, C) we can apply the predictions (up to the serial for
that event) and verify that window B is above C.
If we ever receive spurious stacking events (with a serial older than we
would expect) or find an inconsistency (some things aren't possible to
predict from the compositor) then we hit a re-synchronization code-path
that will query the X server for the full stacking order and then use
that stack to walk through our combined stack and force the X windows to
match the just queried stack but avoiding disrupting the relative
stacking of Wayland windows. This will be relatively expensive but
shouldn't be hit for compositor initiated restacking operations where
our predictions should be accurate.
The code in core/stack.c that deals with synchronizing the window stack
with the X server had to be updated quite heavily. In general the patch
avoids changing the fundamental approach being used but most of the code
did need some amount of re-factoring to consider what re-stacking
operations actually involve X or not and when we need to restack X
windows we sometimes need to search for a suitable X sibling to restack
relative too since the closest siblings may be Wayland windows.
Trying to track the fullscreen status outside of Mutter, as GNOME Shell
was doing previously, was very prone to errors, because Mutter has a
very tricky definition of when a window is set to be fullscreen and
*actually* acting like a fullscreen window.
* Add meta_screen_get_monitor_in_fullscreen() and an
::in-fullscreen-changed signal. This allows an application to
track when there are fullscreen windows on a monitor.
* Do the computation of fullscreen status in a "later" function that
runs after showing, so we properly take focus into account.
* To get ordering of different phases right, add more values
to MetaLaterType.
* Add auto-minimization, similar to what was added to GNOME Shell
earlier in this cycle - if a window is set to be fullscreen, but
not actually fullscreen, minimize.
https://bugzilla.gnome.org/show_bug.cgi?id=649748
If mutter is going to be a "real" library, then it should install its
includes so that users can do
#include <meta/display.h>
rather than
#include <display.h>
So rename the includedir accordingly, move src/include to src/meta,
and fix up all internal references.
There were a handful of header files in src/include that were not
installed; this appears to have been part of a plan to keep core/,
ui/, and compositor/ from looking at each others' private includes,
but that wasn't really working anyway. So move all non-installed
headers back into core/ or ui/.
https://bugzilla.gnome.org/show_bug.cgi?id=643959
Since we can't distinguish a ConfigureEvent that indicates a raise
from a ConfigureEvent that indicates a move, we get lots of
STACK_OP_RAISE_ABOVE events for windows that are already in the
right place in the stacking order. Avoid queueing a restack in that
case.
https://bugzilla.gnome.org/show_bug.cgi?id=634771
