ec73076e07
It forced the power save mode to META_POWER_SAVE_ON when reading the current KMS state. This was problematic when a hotplug event is emitted while the session is locked, which can be triggered by monitors polling all their inputs for a signal: There's no mechanism to restore the previous power save mode in this case, so the monitors would fail to actually enter power saving mode but stayed on with a blank screen. This was at least one cause of the symptoms described in https://gitlab.freedesktop.org/drm/amd/-/issues/662 . Moreover, I suspect it hasn't had any effect for the actual reading of KMS state since 5f6aee341959 ("kms/update: Make power saving an update wide change"), as changing the power save mode to META_POWER_SAVE_ON no longer results in any immediate KMS state change, it's now only taken into account for the next mode set. It's not clear what the intended effect was in the first place, it was originally added as part of 65db8efbe8b1 ("MonitorManager: add a KMS backend") without rationale. It might have been cargo-culted from somewhere else. It shouldn't be necessary from a KMS API PoV though. Also adjust the KMS hotplug test to assert that a hotplug event doesn't implicitly change the power save mode. v2: (Sebastian Wick) * Fix shortlog of commit which added meta_monitor_manager_native_read_current_state. v3: * Adjust KMS hotplug test for the change. Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/4209>
Mutter
Mutter is a Wayland display server and X11 window manager and compositor library.
When used as a Wayland display server, it runs on top of KMS and libinput. It implements the compositor side of the Wayland core protocol as well as various protocol extensions. It also has functionality related to running X11 applications using Xwayland.
When used on top of Xorg it acts as a X11 window manager and compositing manager.
It contains functionality related to, among other things, window management, window compositing, focus tracking, workspace management, keybindings and monitor configuration.
Internally it uses a fork of Cogl, a hardware acceleration abstraction library used to simplify usage of OpenGL pipelines, as well as a fork of Clutter, a scene graph and user interface toolkit.
Mutter is used by, for example, GNOME Shell, the GNOME core user interface, and by Gala, elementary OS's window manager. It can also be run standalone, using the command "mutter", but just running plain mutter is only intended for debugging purposes.
Contributing
To contribute, open merge requests at https://gitlab.gnome.org/GNOME/mutter.
It can be useful to first look at the GNOME Handbook and the documentation and API references below first.
Documentation
- Coding style and conventions
- Git conventions
- Code overview
- Building and Running
- Debugging
- Monitor configuration
- Multi-GPU
API Reference
- Meta: https://mutter.gnome.org/meta/
- Clutter: https://mutter.gnome.org/clutter/
- Cogl: https://mutter.gnome.org/cogl/
- Mtk: https://mutter.gnome.org/mtk/
Meetings
There are recurring meetings to discuss development of GNOME Shell, mutter and related components.
License
Mutter is distributed under the terms of the GNU General Public License, version 2 or later. See the COPYING file for detalis.