Implement the set_acquire_fence request of the
zwp_surface_synchronization_v1 interface.
The implementation uses the acquire fence in two ways:
1. If the associated buffer is used as GL render source, an
EGLSyncKHR is created from the fence and used to synchronize
access.
2. If the associated buffer is used as a plane framebuffer,
the acquire fence is treated as an in-fence for the atomic
commit operation. If in-fences are not supported and the buffer
has an acquire fence, we don't consider it for plane placement.
If the used compositor/renderer doesn't support explicit
synchronization, we don't advertise the protocol at all. Currently only
the DRM and X11 backends when using the GL renderer advertise the
protocol for production use.
Issues for discussion
---------------------
a. Currently, a server-side wait of EGLSyncKHR is performed before
using the EGLImage/texture during rendering. Unfortunately, it's not clear
from the specs whether this is generally safe to do, or we need to
sync before glEGLImageTargetTexture2DOES. The exception is
TEXTURE_EXTERNAL_OES where the spec mentions it's enough to sync
and then glBindTexture for any changes to take effect.
Changes in v5:
- Meson support.
- Make explicit sync server error reporting more generic, supporting
all explicit sync related interfaces not just
wp_linux_surface_synchronization.
- Fix typo in warning for missing EGL_KHR_wait_sync extension.
- Support minor version 2 of the explicit sync protocol (i.e., support
fences for opaque EGL buffers).
Changes in v4:
- Introduce and use fd_clear and and fd_move helpers.
- Don't check for a valid buffer when updating surface acquire fence fd
from state.
- Assert that pending state acquire fence fd is always clear
after a commit.
- Clarify that WESTON_CAP_EXPLICIT_SYNC applies to just the
renderer.
- Check for EGL_KHR_wait_sync before using eglWaitSyncKHR.
- Dup the acquire fence before passing to EGL.
Changes in v3:
- Keep acquire_fence_fd in surface instead of buffer.
- Clarify that WESTON_CAP_EXPLICIT_SYNC applies to both backend and
renderer.
- Move comment about non-ownership of in_fence_fd to struct
drm_plane_state definition.
- Assert that we don't try to use planes with in-fences when using the
legacy KMS API.
- Remove unnecessary info from wayland error messages.
- Handle acquire fence for subsurface commits.
- Guard against self-update in fd_update.
- Disconnect the client if acquire fence EGLSyncKHR creation or wait
fails.
- Use updated protocol interface names.
- User correct format specifier for resource ids.
- Advertise protocol for X11 backend with GL renderer.
Changes in v2:
- Remove sync file wait fallbacks.
- Raise UNSUPPORTED_BUFFER error at commit if we have an acquire
fence, but the committed buffer is not a valid linux_dmabuf.
- Don't put buffers with in-fences on planes that don't support
in-fences.
- Don't advertise explicit sync protocol if backend does not
support explicit sync.
Signed-off-by: Alexandros Frantzis <alexandros.frantzis@collabora.com>
Introduce support for the zwp_linux_explicit_synchronization_unstable_v1
protocol with an implementation of the zwp_linux_explicit_synchronization_v1
interface.
Explicit synchronization provides a more versatile notification
mechanism for buffer readiness and availability, and can be used to
improve efficiency by integrating with related functionality in display
and graphics APIs.
In addition, the per-commit nature of the release events provided by
this protocol potentially offers a solution to a deficiency of the
wl_buffer.release event (see
https://gitlab.freedesktop.org/wayland/wayland/issues/46).
Support for this protocol depends on the capabilities of the backend, so
we don't register it by default but provide a function which each
backend will need to call. In this commit only the headless backend when
using the noop renderer supports this to enable testing.
Note that the zwp_surface_synchronization_v1 interface, which contains
the core functionality of the protocol, is not implemented in this
commit. Support for it will be added in future commits.
Changes in v7:
- Added some information in the commit message about the benefits of
the explicit sync protocol.
Changes in v6:
- Fall back to advertising minor version 1 of the explicit sync protocol,
although we support minor version 2 features, until the new
wayland-protocols version is released.
Changes in v5:
- Meson support.
- Advertise minor version 2 of the explicit sync protocol.
Changes in v4:
- Enable explicit sync support in the headless backend for all
renderers.
Changes in v3:
- Use wl_resource_get_version() instead of hardcoding version 1.
- Use updated protocol interface names.
- Use correct format specifier for resource id.
- Change test name to 'linux-explicit-synchronization.weston'
(s/_/-/g).
Changes in v2:
- Move implementation to separate file so protocol can be registered
on demand by backends.
- Register protocol in headless+noop backend for testing purposes.
Signed-off-by: Alexandros Frantzis <alexandros.frantzis@collabora.com>
weston-launch starts weston and provides mechanism
for weston to set/drop drm master, open a tty,
and read input devices without being root.
Execution is allowed for local-active sessions
or users in the group weston-launch.
This rename addresses a few problems around the split between core
Wayland and the wayland-demos repository.
1) Initially, we had one big repository with protocol code, sample
compositor and sample clients. We split that repository to make it
possible to implement the protocol without pulling in the sample/demo
code. At this point, the compositor is more than just a "demo" and
wayland-demos doesn't send the right message. The sample compositor
is a useful, self-contained project in it's own right, and we want to
move away from the "demos" label.
2) Another problem is that the wayland-demos compositor is often
called "the wayland compsitor", but it's really just one possible
compositor. Existing X11 compositors are expected to add Wayland
support and then gradually phase out/modularize the X11 support, for
example. Conversely, it's hard to talk about the wayland-demos
compositor specifically as opposed to, eg, the wayland protocol or a
wayland compositor in general.
We are also renaming the repo to weston, and the compositor
subdirectory to src/, to emphasize that the main "output" is the
compositor.
Besides the new header file, there's also a change in the main evdev creation
procedure for a more suggestive name (evdev_input_add_devices ->
evdev_input_create). There's no real functional changes in this commit.
Signed-off-by: Tiago Vignatti <tiago.vignatti@intel.com>
Alexandros Frantzis
Bryce Harrington
Peter Hutterer
Benjamin Franzke
Kristian Høgsberg
Tiago Vignatti