kc3-lang/angle/extensions/EGL_ANGLE_global_fence_sync.txt

Branch - branch -main

• Show log

  Commit

• Hash : b380ed1f
  Author :
  Date : 2024-02-14T09:31:26
  

  Vulkan: Add EGL_ANGLE_global_fence_sync
  
  Chrome has an implicit assumption that due to context virtualization,
  signaling a fence in one context results in synchronization with _all_
  contexts that have previously made submissions.
  
  This is not per EGL spec, but the functionality is easily implementable
  in the Vulkan backend.  In the Vulkan backend, each context is given its
  own "timeline" of submissions (tracked by serials associated with
  "indices").  The required functionality is implemented through a new EGL
  fence sync object whose sole difference is that it synchronizes with all
  the existing timelines rather than the one of the current context.
  
  Bug: b/318721705
  Change-Id: I6c45d065e592d0d4ed627ce9695196b1086d5021
  Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5297396
  Reviewed-by: Charlie Lao <cclao@google.com>
  Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
  

Download

• extensions/EGL_ANGLE_global_fence_sync.txt

• Name
  
      ANGLE_global_fence_sync
  
  Name Strings
  
      EGL_ANGLE_global_fence_sync
  
  Contributors
  
      Shahbaz Youssefi, Google
  
  Contacts
  
      Shahbaz Youssefi, Google (syoussefi 'at' google.com)
  
  Status
  
      Draft
  
  Version
  
      Version 1, 2024-02-13
  
  Number
  
      EGL Extensions XXX
  
  Extension Type
  
      EGL display extension
  
  Dependencies
  
      This extension is written against the wording of the EGL 1.5
      Specification.
  
  Overview
  
      This extension enables the creation of EGL fence sync objects that
      synchronize with all past submissions of all contexts.  Normally, if two
      contexts make submissions, even on the same thread, the inserted fence sync
      only guarantees synchronization with the submissions from the context in
      which the fence was inserted.  With the new fence sync type introduced by
      this extension, the application can synchronize with both contexts in this
      example using a single fence.
  
  New Types
  
      None.
  
  New Procedures and Functions
  
      None.
  
  New Tokens
  
      Accepted by the <type> parameter of eglCreateSync, and returned
      in <value> when eglGetSyncAttrib is called with <attribute>
      EGL_SYNC_TYPE:
  
      EGL_SYNC_GLOBAL_FENCE_ANGLE                         0x34DE
  
  Additions to the EGL Specification
  
      Add the following after the second paragraph of Section 3.8.1.1 (Creating
      Fence Sync Objects),
  
      "If <type> is EGL_SYNC_GLOBAL_FENCE_ANGLE, behavior is identical to
      EGL_SYNC_FENCE except that synchronization is additionally done with all
      previously submitted commands by all contexts."
  
      In the Errors of eglCreateSync, replace all instances of "If type is
      EGL_SYNC_FENCE" with "If type is EGL_SYNC_FENCE or
      EGL_SYNC_GLOBAL_FENCE_ANGLE".
  
  Issues
  
      None.
  
  Revision History
  
      Version 1, 2024-02-13
        - Initial draft
  
  

Download