79 lines
2.4 KiB
Plaintext
79 lines
2.4 KiB
Plaintext
// Copyright (c) 2016-2019 Khronos Group. This work is licensed under a
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// Creative Commons Attribution 4.0 International License; see
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// http://creativecommons.org/licenses/by/4.0/
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include::meta/VK_KHR_external_semaphore.txt[]
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*Last Modified Date*::
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2016-10-21
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*IP Status*::
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No known IP claims.
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*Interactions and External Dependencies*::
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- Promoted to Vulkan 1.1 Core
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*Contributors*::
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- Jason Ekstrand, Intel
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- Jesse Hall, Google
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- Tobias Hector, Imagination Technologies
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- James Jones, NVIDIA
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- Jeff Juliano, NVIDIA
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- Matthew Netsch, Qualcomm Technologies, Inc.
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- Ray Smith, ARM
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- Chad Versace, Google
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An application using external memory may wish to synchronize access to that
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memory using semaphores.
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This extension enables an application to create semaphores from which
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non-Vulkan handles that reference the underlying synchronization primitive
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can be exported.
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=== New Object Types
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None.
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=== New Enum Constants
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* ename:VK_STRUCTURE_TYPE_EXPORT_SEMAPHORE_CREATE_INFO_KHR
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* ename:VK_ERROR_INVALID_EXTERNAL_HANDLE_KHR
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=== New Enums
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* elink:VkSemaphoreImportFlagBitsKHR
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=== New Structs
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* slink:VkExportSemaphoreCreateInfoKHR
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=== New Functions
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None.
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=== Promotion to Vulkan 1.1
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All functionality in this extension is included in core Vulkan 1.1, with the
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KHR suffix omitted.
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The original type, enum and command names are still available as aliases of
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the core functionality.
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=== Issues
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1) Should there be restrictions on what side effects can occur when waiting
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on imported semaphores that are in an invalid state?
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*RESOLVED*: Yes.
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Normally, validating such state would be the responsibility of the
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application, and the implementation would be free to enter an undefined:
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state if valid usage rules were violated.
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However, this could cause security concerns when using imported semaphores,
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as it would require the importing application to trust the exporting
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application to ensure the state is valid.
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Requiring this level of trust is undesirable for many potential use cases.
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2) Must implementations validate external handles the application provides
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as input to semaphore state import operations?
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*RESOLVED*: Implementations must return an error to the application if the
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provided semaphore state handle cannot be used to complete the requested
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import operation.
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However, implementations need not validate handles are of the exact type
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specified by the application.
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