Summary:
The base idea behind this change is to keep the system responsive no
matter what other processes do. All input and rendering needs to go
through the windowing system, so keeping it responsive is important.
Currently KWin competes with all other processes for resources and this
can render the system unusable. Consider some processes running amok. In
this case the user might not be able to easily close the applications as
KWin does not get the cpu time to perform the input tasks requested by
the user.
Or in the case of playing a demanding game it is important that KWin
gets scheduled to forward the pointer input events. The user doesn't
want that the game (or another process) wins against the windowing
sytem.
The disadvantage is that KWin always wins against other processes with
real time scheduling. This could result in KWin running amok stalling
the system. On the other hand this is no change to the current situation
as if KWin runs amok the sytem is unusable.
The change uses libcap to set CAP_SYS_NICE on kwin_wayland executable.
KWin_wayland on start sets the scheduling policy to SCHED_RR with the
lowest possible priority. Thus any other SCHED_RR process will win
against KWin. So real time processes are not affected by this change!
After adjusting the scheduling (which requires CAP_SYS_NICE) KWin drops
this capability again.
Test Plan:
Verified that KWin adjusts the scheduler, that it is not passed
to child processes, that the capability gets dropped and not passed to
child processes.
Reviewers: #kwin, #plasma
Subscribers: plasma-devel, kwin
Tags: #kwin
Differential Revision: https://phabricator.kde.org/D7757
A recent change [1] led to Qt5PlatformSupport.pc not being installed
anymore. Pkg-config was only used for finding the paths, and the actual
include flags and library names were hardcoded in KWin's
FindQt5PlatformSupport.cmake anyway, so let's just focus on finding
Qt5Gui, the module which provides this Qt5PlatformSupport library, and
work from there.
Thanks to Hrvoje Senjan (shumski) for pointing me towards the upstream
Gerrit change.
[1] https://codereview.qt-project.org/140954/
REVIEW: 126234
So far it was bound to whether we build for GLES. But this is
semantically wrong. It might be possible that even on desktop gl
epoxy is built without GLX support, thus we need to reflect this.
This change ensures that epoxy/glx.h is only included if available,
that relevant code is bound to it and that checks are in place to
enforce EGL if not build with glx support.
In addtion the glxbackend.cpp is now only included in the build set
if available.
Libinput does work on libhybris enabled devices. There is no need to
use Android's input stack. This simplifies our code a lot and increases
sharing with normal Linux systems.
What's tricky is to convince the system to use libinput through with our
logind helper. Logind fails to open the files for us if we start KWin
over either ssh or adb shell. We need to get it into a proper session, so
only a kwin started through a helper like simplelogin will be able to use
libinput.
REVIEW: 125608
The one contains a set of paths which might be the reason why e.g on the
CI the include dir cannot be constructed. Let's see what will happen....
CCBUG: 351776
This introduces an own QPA plugin for KWin. QtWayland's plugin is not
a good solution for KWin as QtWayland is meant for Wayland clients and
not for a Wayland server. Given that it makes more sense to have a very
minimal QPA plugin which supports the use cases we actually have.
With our own QPA plugin we should be able to improve the following
areas:
* no need to create Wayland server before QApplication
* Qt::BypassWindowManagerHint can be supported
* no workaround for creating OpenGL context in main thread
* sharing OpenGL context with Qt
* OpenGL context for Qt on libhybris backend
The plugin supports so far the following features:
* creating a QPlatformWindow using KWayland::Client (ShellSurface)
* creating a QPlatformBackingStore using a ShmPool
* creating a QPlatformOpenGLContext with Wayland::EGL
* or creating a QPlatformOpenGLContext which shares with KWin's scene
* creating a QPlatformScreen for each KWayland::Client::Output
* QPlatformNativeInterface compatible to QtWayland
Unfortunately on libhybris enabled systems libinput doesn't work, thus
the backend needs to handle input events which can be read from hybris.
So far the backend only handles touch events properly, though some
aspects look wrong. E.g. motion gives only for one touch contact point.
Unfortunately the documentation is quite weak, so there might be
something important missing.
This backend interacts with libhybris to create a hwcomposer which is
used for creating the egl context and surface. The initial version of
this backend is based on test_hwcomposer.cpp provided by libhybris.
Please note that using the hwcomposer backend requires a newer libepoxy,
the latest stable release is not able to bring up OpenGLES, so one needs
a master build of libepoxy.
Notes on licensing:
libhybris is Apache 2.0 licensed, which is not compatile with GPLv2.
But it is compatible with GPLv3. Thus the source files in the hwcomposer
backend are licensed GPLv3+ and not GPLv2+ as the rest of KWin. If one
uses KWin without the hwcomposer backend (which is obviously the default)
the licence doesn't change. But if the hwcomposer backend is used the
overall license of KWin changes to GPLv3+.
Uses EGL_MESA_platform_gbm to get an EglDisplay from a gbm_device.
The DrmBackend can provide a DrmBuffer for a gbm_surface and present
it.
Unfortunately buffer age seems to be slightly broken and we still have
artefacts.
Introduces a new (optional) dependency: libdrm.
The DrmBackend currently supports finding the first connected output.
It can create shared memory buffers which are used by SceneQPainter to
do double buffered rendering.
There is still lots to do, the following things are not yet working:
* multiple outputs
* page flip
* OpenGL (through gbm)
* restoring mode setting to start value
As we use epoxy we don't need them any more. KWin compiles, links and
runs just fine without ever trying to find OpenGL or OpenGLES.
BUG: 340170
FIXED-IN: 5.2.0
Libinput is an optional dependency for getting low level input events.
As opening the input devices requires root privs this is rather
pointless in the current state. But there is a small added test app which
can be executed with root privs to demonstrate the functionality. To
properly get input events we need a wrapper like it's used in weston.
So far the following is setup:
* opening devices found by udev
* forwarding keyboard events to InputRedirection
* forwarding pointer button events to InputRedirection
* forwarding pointer axis events to InputRedirection
* signals emitted for pointer motion events
Pointer motion events need some further work as they are provided
as delta events. We need to track that and map them properly.
Also missing are touch events due to me not having a touch screen.
It should be fairly simple to setup the touch events, though.
Also hotplugging of devices is not yet implemented.
