[PATCH wayland-protocols v6] Add zwp_linux_explicit_synchronization_v1
Alexandros Frantzis
alexandros.frantzis at collabora.com
Wed Nov 7 14:59:25 UTC 2018
Signed-off-by: Alexandros Frantzis <alexandros.frantzis at collabora.com>
---
Changes in patch v6:
- Fixed wl_buffer.attach -> wl_surface.attach typos.
- Added NO_BUFFER error and updated request descriptions.
- Consistently used "error is raised" phrasing.
- Added comment about buffer_release object destruction in event
descriptions.
Changes in patch v5:
- Further clarified the per-commit nature of buffer_release.
- Used the wp_linux_dmabuf name to refer to all versions of that protocol.
- Fixed wl_buffer.attach typo.
- Clarified when an INVALID_FENCE error is raised.
- Improved wording explaining the double-buffer state of buffer_release.
- Allowed get_release requests on all non-null buffers.
- Clarified that the compositor is free to select buffer_release events
on a release by release basis.
- Changed buffer_release to be self-destroyed after it emits an event.
Changes in patch v4:
- Guaranteed protocol compatibility only with zwp_linux_dmabuf buffers.
- Added the UNSUPPORTED_BUFFER error.
Changes in patch v3:
- Reworded implicit/explicit synchronization intro in
zwp_surface_synchronization_v1 description.
- Removed confusing mention of wl_buffer.release in
zwp_surface_synchronization_v1 description.
- Clarified which fences are affected on sync object destruction.
- Removed unclear mention about wl_buffer destruction
in fenced_release description.
- Clarified that the release events and their guarantees apply to
the relevant commit only.
- Reformatted text.
Changes in patch v2:
- Added NO_SURFACE error for zwp_surface_synchronization_v1 requests.
- Removed restriction to destroy a zwp_surface_synchronization_v1 object
after the associated wl_surface is destroyed.
- Clarified which buffer the acquire fence is associated with.
- Clarified that exactly one event, either a fenced_release or a
immediate_release, will be emitted for each commit.
Makefile.am | 1 +
.../linux-explicit-synchronization/README | 6 +
...x-explicit-synchronization-unstable-v1.xml | 234 ++++++++++++++++++
3 files changed, 241 insertions(+)
create mode 100644 unstable/linux-explicit-synchronization/README
create mode 100644 unstable/linux-explicit-synchronization/linux-explicit-synchronization-unstable-v1.xml
diff --git a/Makefile.am b/Makefile.am
index 6394e26..7dfbb9e 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -21,6 +21,7 @@ unstable_protocols = \
unstable/xdg-output/xdg-output-unstable-v1.xml \
unstable/input-timestamps/input-timestamps-unstable-v1.xml \
unstable/xdg-decoration/xdg-decoration-unstable-v1.xml \
+ unstable/linux-explicit-synchronization/linux-explicit-synchronization-unstable-v1.xml \
$(NULL)
stable_protocols = \
diff --git a/unstable/linux-explicit-synchronization/README b/unstable/linux-explicit-synchronization/README
new file mode 100644
index 0000000..f13b404
--- /dev/null
+++ b/unstable/linux-explicit-synchronization/README
@@ -0,0 +1,6 @@
+Linux explicit synchronization (dma-fence) protocol
+
+Maintainers:
+David Reveman <reveman at chromium.org>
+Daniel Stone <daniels at collabora.com>
+Alexandros Frantzis <alexandros.frantzis at collabora.com>
diff --git a/unstable/linux-explicit-synchronization/linux-explicit-synchronization-unstable-v1.xml b/unstable/linux-explicit-synchronization/linux-explicit-synchronization-unstable-v1.xml
new file mode 100644
index 0000000..b87663f
--- /dev/null
+++ b/unstable/linux-explicit-synchronization/linux-explicit-synchronization-unstable-v1.xml
@@ -0,0 +1,234 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<protocol name="zwp_linux_explicit_synchronization_unstable_v1">
+
+ <copyright>
+ Copyright 2016 The Chromium Authors.
+ Copyright 2017 Intel Corporation
+ Copyright 2018 Collabora, Ltd
+
+ Permission is hereby granted, free of charge, to any person obtaining a
+ copy of this software and associated documentation files (the "Software"),
+ to deal in the Software without restriction, including without limitation
+ the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ and/or sell copies of the Software, and to permit persons to whom the
+ Software is furnished to do so, subject to the following conditions:
+
+ The above copyright notice and this permission notice (including the next
+ paragraph) shall be included in all copies or substantial portions of the
+ Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ DEALINGS IN THE SOFTWARE.
+ </copyright>
+
+ <interface name="zwp_linux_explicit_synchronization_v1" version="1">
+ <description summary="protocol for providing explicit synchronization">
+ This global is a factory interface, allowing clients to request
+ explicit synchronization for buffers on a per-surface basis.
+
+ See zwp_surface_synchronization_v1 for more information.
+
+ This interface is derived from Chromium's
+ zcr_linux_explicit_synchronization_v1.
+
+ Warning! The protocol described in this file is experimental and
+ backward incompatible changes may be made. Backward compatible changes
+ may be added together with the corresponding interface version bump.
+ Backward incompatible changes are done by bumping the version number in
+ the protocol and interface names and resetting the interface version.
+ Once the protocol is to be declared stable, the 'z' prefix and the
+ version number in the protocol and interface names are removed and the
+ interface version number is reset.
+ </description>
+
+ <request name="destroy" type="destructor">
+ <description summary="destroy explicit synchronization factory object">
+ Destroy this explicit synchronization factory object. Other objects,
+ including zwp_surface_synchronization_v1 objects created by this
+ factory, shall not be affected by this request.
+ </description>
+ </request>
+
+ <enum name="error">
+ <entry name="synchronization_exists" value="0"
+ summary="the surface already has a synchronization object associated"/>
+ </enum>
+
+ <request name="get_synchronization">
+ <description summary="extend surface interface for explicit synchronization">
+ Instantiate an interface extension for the given wl_surface to provide
+ explicit synchronization.
+
+ If the given wl_surface already has an explicit synchronization object
+ associated, the synchronization_exists protocol error is raised.
+ </description>
+
+ <arg name="id" type="new_id" interface="zwp_surface_synchronization_v1"
+ summary="the new synchronization interface id"/>
+ <arg name="surface" type="object" interface="wl_surface"
+ summary="the surface"/>
+ </request>
+ </interface>
+
+ <interface name="zwp_surface_synchronization_v1" version="1">
+ <description summary="per-surface explicit synchronization support">
+ This object implements per-surface explicit synchronization.
+
+ Synchronization refers to co-ordination of pipelined operations performed
+ on buffers. Most GPU clients will schedule an asynchronous operation to
+ render to the buffer, then immediately send the buffer to the compositor
+ to be attached to a surface.
+
+ In implicit synchronization, ensuring that the rendering operation is
+ complete before the compositor displays the buffer is an implementation
+ detail handled by either the kernel or userspace graphics driver.
+
+ By contrast, in explicit synchronization, dma_fence objects mark when the
+ asynchronous operations are complete. When submitting a buffer, the
+ client provides an acquire fence which will be waited on before the
+ compositor accesses the buffer. The Wayland server, through a
+ zwp_buffer_release_v1 object, will inform the client with an event which
+ may be accompanied by a release fence, when the compositor will no longer
+ access the buffer contents due to the specific commit that requested the
+ release event.
+
+ Each surface can be associated with only one object of this interface at
+ any time.
+
+ Explicit synchronization is guaranteed to be supported only for buffers
+ created with any version of the wp_linux_dmabuf buffer factory.
+ </description>
+
+ <request name="destroy" type="destructor">
+ <description summary="destroy synchronization object">
+ Destroy this explicit synchronization object.
+
+ Any fence set by this object with set_acquire_fence since the last
+ commit will be discarded by the server. Any fences set by this object
+ before the last commit are not affected.
+
+ zwp_buffer_release_v1 objects created by this object are not affected
+ by this request.
+ </description>
+ </request>
+
+ <enum name="error">
+ <entry name="invalid_fence" value="0"
+ summary="the fence specified by the client could not be imported"/>
+ <entry name="duplicate_fence" value="1"
+ summary="multiple fences added for a single surface commit"/>
+ <entry name="duplicate_release" value="2"
+ summary="multiple releases added for a single surface commit"/>
+ <entry name="no_surface" value="3"
+ summary="the associated wl_surface was destroyed"/>
+ <entry name="unsupported_buffer" value="4"
+ summary="the buffer does not support explicit synchronization"/>
+ <entry name="no_buffer" value="5"
+ summary="no buffer was attached"/>
+ </enum>
+
+ <request name="set_acquire_fence">
+ <description summary="set the acquire fence">
+ Set the acquire fence that must be signaled before the compositor
+ may sample from the buffer attached with wl_surface.attach. The fence
+ is a dma_fence kernel object.
+
+ The acquire fence is double-buffered state, and will be applied on the
+ next wl_surface.commit request for the associated surface. Thus, it
+ applies only to the buffer that is attached to the surface at commit
+ time.
+
+ If the provided fd is not a valid dma_fence fd, then an INVALID_FENCE
+ error is raised.
+
+ If a fence has already been attached during the same commit cycle, a
+ DUPLICATE_FENCE error is raised.
+
+ If the associated wl_surface was destroyed, a NO_SURFACE error is
+ raised.
+
+ If at surface commit time the attached buffer does not support explicit
+ synchronization, an UNSUPPORTED_BUFFER error is raised.
+
+ If at surface commit time there is no buffer attached, a NO_BUFFER
+ error is raised.
+ </description>
+ <arg name="fd" type="fd" summary="acquire fence fd"/>
+ </request>
+
+ <request name="get_release">
+ <description summary="release fence for last-attached buffer">
+ Create a listener for the release of the buffer attached by the
+ client with wl_surface.attach. See zwp_buffer_release_v1
+ documentation for more information.
+
+ The release object is double-buffered state, and will be associated
+ with the buffer that is attached to the surface at wl_surface.commit
+ time.
+
+ If a zwp_buffer_release_v1 object has already been requested for
+ the surface in the same commit cycle, a DUPLICATE_RELEASE error
+ is raised.
+
+ If the associated wl_surface was destroyed, a NO_SURFACE error
+ is raised.
+
+ If at surface commit time there is no buffer attached, a NO_BUFFER
+ error is raised.
+ </description>
+ <arg name="release" type="new_id" interface="zwp_buffer_release_v1"
+ summary="new zwp_buffer_release_v1 object"/>
+ </request>
+ </interface>
+
+ <interface name="zwp_buffer_release_v1" version="1">
+ <description summary="buffer release explicit synchronization">
+ This object is instantiated in response to a
+ zwp_surface_synchronization_v1.get_release request.
+
+ It provides an alternative to wl_buffer.release events, providing a
+ unique release from a single wl_surface.commit request. The release event
+ also supports explicit synchronization, providing a fence FD for the
+ client to synchronize against.
+
+ Exactly one event, either a fenced_release or an immediate_release, will
+ be emitted for the wl_surface.commit request. The compositor can choose
+ release by release which event it uses.
+
+ This event does not replace wl_buffer.release events; servers are still
+ required to send those events.
+
+ Once a buffer release object has delivered a 'fenced_release' or an
+ 'immediate_release' event it is automatically destroyed.
+ </description>
+
+ <event name="fenced_release">
+ <description summary="release buffer with fence">
+ Sent when the compositor has finalised its usage of the associated
+ buffer for the relevant commit, providing a dma_fence which will be
+ signaled when all operations by the compositor on that buffer for that
+ commit have finished.
+
+ This event destroys the zwp_buffer_release_v1 object.
+ </description>
+ <arg name="fence" type="fd" summary="fence for last operation on buffer"/>
+ </event>
+
+ <event name="immediate_release">
+ <description summary="release buffer immediately">
+ Sent when the compositor has finalised its usage of the associated
+ buffer for the relevant commit, and either performed no operations
+ using it, or has a guarantee that all its operations on that buffer for
+ that commit have finished.
+
+ This event destroys the zwp_buffer_release_v1 object.
+ </description>
+ </event>
+ </interface>
+
+</protocol>
--
2.19.1
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