1// Copyright 2016-2021 The Khronos Group, Inc. 2// 3// SPDX-License-Identifier: CC-BY-4.0 4 5include::{generated}/meta/{refprefix}VK_KHR_external_semaphore.txt[] 6 7=== Other Extension Metadata 8 9*Last Modified Date*:: 10 2016-10-21 11*IP Status*:: 12 No known IP claims. 13*Interactions and External Dependencies*:: 14 - Promoted to Vulkan 1.1 Core 15*Contributors*:: 16 - Jason Ekstrand, Intel 17 - Jesse Hall, Google 18 - Tobias Hector, Imagination Technologies 19 - James Jones, NVIDIA 20 - Jeff Juliano, NVIDIA 21 - Matthew Netsch, Qualcomm Technologies, Inc. 22 - Ray Smith, ARM 23 - Chad Versace, Google 24 25=== Description 26 27An application using external memory may wish to synchronize access to that 28memory using semaphores. 29This extension enables an application to create semaphores from which 30non-Vulkan handles that reference the underlying synchronization primitive 31can be exported. 32 33=== Promotion to Vulkan 1.1 34 35All functionality in this extension is included in core Vulkan 1.1, with the 36KHR suffix omitted. 37The original type, enum and command names are still available as aliases of 38the core functionality. 39 40include::{generated}/interfaces/VK_KHR_external_semaphore.txt[] 41 42=== Issues 43 441) Should there be restrictions on what side effects can occur when waiting 45on imported semaphores that are in an invalid state? 46 47*RESOLVED*: Yes. 48Normally, validating such state would be the responsibility of the 49application, and the implementation would be free to enter an undefined: 50state if valid usage rules were violated. 51However, this could cause security concerns when using imported semaphores, 52as it would require the importing application to trust the exporting 53application to ensure the state is valid. 54Requiring this level of trust is undesirable for many potential use cases. 55 562) Must implementations validate external handles the application provides 57as input to semaphore state import operations? 58 59*RESOLVED*: Implementations must return an error to the application if the 60provided semaphore state handle cannot be used to complete the requested 61import operation. 62However, implementations need not validate handles are of the exact type 63specified by the application. 64 65=== Version History 66 67 * Revision 1, 2016-10-21 (James Jones) 68 - Initial revision 69