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[UR] Implement IPC physical_mem API in UR#22115

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[UR] Implement IPC physical_mem API in UR#22115
ldorau wants to merge 3 commits into
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ldorau:UR_Implement_IPC_physical_mem_API_in_UR

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@ldorau ldorau commented May 26, 2026 •
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Implement urIPCGetPhysMemHandleExp, urIPCPutPhysMemHandleExp,
urIPCOpenPhysMemHandleExp, and urIPCClosePhysMemHandleExp across all
adapters.

Level Zero adapter (full implementation, Linux only)

  • Extend ur_physical_mem_handle_t_ with Device, Size, EnableIpc,
    and IpcVirtualAddress fields; ZeIPCPhysMemHandleData holds a
    ze_ipc_mem_handle_t + size (self-contained 64-byte opaque blob).
  • Producer calls zeMemGetIpcHandleWithProperties with
    ze_ipc_mem_handle_type_ext_desc_t / ZE_IPC_MEM_HANDLE_TYPE_FLAG_DEFAULT,
    passing the ze_physical_mem_handle_t cast to const void* (spec-defined
    behavior). Older drivers may return ZE_RESULT_ERROR_INVALID_ARGUMENT
    instead of ZE_RESULT_ERROR_UNSUPPORTED_FEATURE; both are mapped to
    UR_RESULT_ERROR_UNSUPPORTED_FEATURE.
  • Consumer calls zeMemOpenIpcHandle which establishes the virtual mapping
    directly; the pointer is stored in IpcVirtualAddress.
  • urVirtualMemMap is a no-op for IPC-opened handles.
  • Report UR_DEVICE_INFO_IPC_PHYSICAL_MEMORY_SUPPORT_EXP as true on
    Linux, false on Windows.

Other adapters (CUDA, HIP, OpenCL, Native CPU, Offload)

  • Return UR_RESULT_ERROR_UNSUPPORTED_FEATURE from all four functions.
  • Report UR_DEVICE_INFO_IPC_PHYSICAL_MEMORY_SUPPORT_EXP as false.

Conformance tests

  • Add tests for all four entry points with shared fixtures.
  • Tests skip when the feature is unsupported (device info query or runtime
    UR_RESULT_ERROR_UNSUPPORTED_FEATURE from urIPCGetPhysMemHandleExp).

@ldorau ldorau requested a review from slawekptak May 26, 2026 09:53
slawekptak
slawekptak reviewed May 26, 2026
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Comment thread unified-runtime/include/unified-runtime/ur_api.h
Comment thread unified-runtime/source/adapters/level_zero/memory.cpp Outdated
Comment thread unified-runtime/source/adapters/opencl/common.hpp Outdated
Comment thread unified-runtime/test/conformance/virtual_memory/ze_ipc_phys_mem_e2e.cpp Outdated
@ldorau ldorau force-pushed the UR_Implement_IPC_physical_mem_API_in_UR branch from 70701a0 to 523e104 Compare May 26, 2026 12:02
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ldorau commented May 26, 2026

Rebased

@ldorau ldorau requested a review from slawekptak May 26, 2026 12:02
@ldorau ldorau force-pushed the UR_Implement_IPC_physical_mem_API_in_UR branch from 523e104 to 4cbcfa8 Compare May 26, 2026 14:30
@ldorau ldorau marked this pull request as ready for review May 27, 2026 08:22
@ldorau ldorau requested review from a team as code owners May 27, 2026 08:22
@ldorau ldorau requested a review from pbalcer May 27, 2026 08:22
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ldorau commented May 27, 2026 •
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The Offload CI job fails because of #22125

@ldorau ldorau force-pushed the UR_Implement_IPC_physical_mem_API_in_UR branch from a9eb70a to 6dac91d Compare May 27, 2026 11:12
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ldorau commented May 27, 2026

Rebased

@ldorau ldorau force-pushed the UR_Implement_IPC_physical_mem_API_in_UR branch from 29aee2c to 4a61124 Compare May 27, 2026 13:01
@ldorau ldorau marked this pull request as draft May 27, 2026 20:28
@ldorau ldorau force-pushed the UR_Implement_IPC_physical_mem_API_in_UR branch from 6113038 to 572be16 Compare May 28, 2026 08:49
kswiecicki
kswiecicki reviewed May 28, 2026
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Comment thread unified-runtime/source/adapters/level_zero/physical_mem.cpp
ur_physical_mem_handle_t hPhysMem,
void **ppIPCPhysMemHandleData,
size_t *pIPCPhysMemHandleDataSizeRet) {
#ifdef __linux__
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@kswiecicki kswiecicki May 28, 2026

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Are L0 driver IPC calls specific to Linux?

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@ldorau ldorau May 29, 2026

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No, currently only implementation for Linux is needed. A Windows one will differ.

Comment thread unified-runtime/source/adapters/level_zero/physical_mem.cpp Outdated
void **ppIPCPhysMemHandleData,
size_t *pIPCPhysMemHandleDataSizeRet) {
#ifdef __linux__
if (!hContext)
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Majority of those checks should probably be done on the validation layer side.

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@ldorau ldorau May 29, 2026

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Removed

@ldorau ldorau force-pushed the UR_Implement_IPC_physical_mem_API_in_UR branch from 572be16 to 37d96d9 Compare May 28, 2026 10:37
ldorau added 2 commits May 28, 2026 11:23
@ldorau
[UR] Add IPC spec for physical_mem objects
d98f499 
Add four new function specs to exp-inter-process-communication.yml
and update registry.yml to support IPC operations on physical memory
objects:
- urIPCGetPhysMemHandleExp: export an IPC handle for a physical_mem
- urIPCPutPhysMemHandleExp: release the exported IPC handle
- urIPCOpenPhysMemHandleExp: import an IPC handle into a physical_mem
- urIPCClosePhysMemHandleExp: close the imported physical_mem

Also add ENABLE_IPC flag to ur_physical_mem_flags_t in virtual_memory.yml
to allow allocating physical memory that can be shared via IPC handles.

Add a new enumerator to ur_physical_mem_info_t that allows querying the
virtual address established by zeMemOpenIpcHandle when a physical memory
handle is opened via urIPCOpenPhysMemHandleExp.  Returns nullptr for
non-IPC handles.

Signed-off-by: Lukasz Dorau <lukasz.dorau@intel.com>
@ldorau
[UR] Add generated files for IPC physical_mem API
33b8d68 
Add auto-generated files based on the IPC physical_mem spec changes
(urIPCGetPhysMemHandleExp, urIPCPutPhysMemHandleExp,
urIPCOpenPhysMemHandleExp, urIPCClosePhysMemHandleExp,
UR_PHYSICAL_MEM_FLAG_ENABLE_IPC, UR_DEVICE_INFO_IPC_PHYSICAL_MEMORY_SUPPORT_EXP):

- ur_api.h, ur_api_funcs.def, ur_ddi.h: function declarations
- ur_print.h/hpp, ur_print.cpp: printing support
- ur_api.cpp: API dispatch stubs
- ur_ldrddi.cpp, ur_libapi.cpp: loader implementations
- ur_trcddi.cpp, ur_valddi.cpp: tracing and validation layers
- ur_mockddi.cpp: mock adapter
- loader.def.in, loader.map.in: loader symbol exports
- level_zero ur_interface_loader.cpp/.hpp: Level-Zero DDI table entries
- urinfo.hpp: updated urinfo tool

Signed-off-by: Lukasz Dorau <lukasz.dorau@intel.com>
@ldorau ldorau force-pushed the UR_Implement_IPC_physical_mem_API_in_UR branch 4 times, most recently from 75afc3f to 3c08b2b Compare May 29, 2026 13:35
@ldorau
[UR] Implement IPC physical_mem API in UR
3c08b2b 
Implement urIPCGetPhysMemHandleExp, urIPCPutPhysMemHandleExp,
urIPCOpenPhysMemHandleExp, and urIPCClosePhysMemHandleExp across all
adapters.

Level Zero adapter (full implementation, Linux only):
- physical_mem.hpp: extend ur_physical_mem_handle_t_ with Device, Size,
  EnableIpc, and IpcVirtualAddress fields; replace the old pid+fd-based
  ZeIPCPhysMemHandleData with {ze_ipc_mem_handle_t IpcHandle; size_t Size}
  (72-byte self-contained struct; IPC functions are guarded by #ifdef __linux__)
- physical_mem.cpp: implement the four IPC functions matching the approach
  from the Level Zero CTS (commit 2d0d1218 in level-zero.tests):
  * urIPCGetPhysMemHandleExp (producer): calls zeMemGetIpcHandleWithProperties
    passing ze_physical_mem_handle_t cast to (const void*) directly — no prior
    virtual mapping required; uses ze_ipc_mem_handle_type_ext_desc_t with
    ZE_STRUCTURE_TYPE_IPC_MEM_HANDLE_TYPE_EXT_DESC and
    ZE_IPC_MEM_HANDLE_TYPE_FLAG_DEFAULT to request a local same-machine IPC
    handle; detects drivers that return an fd-based handle instead of an opaque
    blob (via fcntl(F_GETFD) on the first 4 bytes) and returns
    UR_RESULT_ERROR_UNSUPPORTED_FEATURE so callers skip gracefully; also maps
    ZE_RESULT_ERROR_INVALID_ARGUMENT / ZE_RESULT_ERROR_UNSUPPORTED_FEATURE from
    the driver to UR_RESULT_ERROR_UNSUPPORTED_FEATURE for graceful skip on
    older drivers that do not support physical-mem IPC at all
  * urIPCOpenPhysMemHandleExp (consumer): calls zeMemOpenIpcHandle with
    ZE_IPC_MEMORY_FLAG_BIAS_UNCACHED, matching the CTS consumer side; stores
    the returned virtual address in IpcVirtualAddress (ZePhysicalMem is null
    on the consumer side)
  * urIPCPutPhysMemHandleExp: calls zeMemPutIpcHandle
  * urIPCClosePhysMemHandleExp: delegates to urPhysicalMemRelease, which calls
    zeMemCloseIpcHandle for IPC-opened handles (IpcVirtualAddress != nullptr)
    and zePhysicalMemDestroy for regular handles
- virtual_mem.cpp: urVirtualMemMap is a no-op for IPC-opened handles since
  zeMemOpenIpcHandle already establishes the virtual mapping
- device.cpp: report UR_DEVICE_INFO_IPC_PHYSICAL_MEMORY_SUPPORT_EXP
  as true on Linux, false on Windows

Other adapters (CUDA, HIP, OpenCL, Native CPU, Offload):
- Return UR_RESULT_ERROR_UNSUPPORTED_FEATURE from all four functions
- Register function pointers in ur_interface_loader.cpp
- Report UR_DEVICE_INFO_IPC_PHYSICAL_MEMORY_SUPPORT_EXP as false

Conformance tests:
- Add urIPCGetPhysMemHandleExp.cpp, urIPCPutPhysMemHandleExp.cpp,
  urIPCOpenPhysMemHandleExp.cpp, urIPCClosePhysMemHandleExp.cpp
- Add urIPCPhysMemHandleExpFixtures.hpp with urIPCPhysMemTest,
  urIPCPhysMemHandleTest, urIPCOpenedPhysMemTest fixtures
- Tests skip when UR_DEVICE_INFO_IPC_PHYSICAL_MEMORY_SUPPORT_EXP is false
  or when urIPCGetPhysMemHandleExp returns UR_RESULT_ERROR_UNSUPPORTED_FEATURE
  at runtime (e.g. on drivers that return fd-based handles)

Signed-off-by: Lukasz Dorau <lukasz.dorau@intel.com>
@ldorau ldorau requested a review from nrspruit May 29, 2026 14:45
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ldorau commented May 29, 2026

@nrspruit please review 2 files: unified-runtime/source/adapters/level_zero/physical_mem.cpp and unified-runtime/source/adapters/level_zero/physical_mem.hpp

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ldorau commented May 29, 2026

The Offload CI job fails because of #22125

@ldorau ldorau marked this pull request as ready for review May 29, 2026 14:55
@ldorau ldorau requested a review from kswiecicki May 29, 2026 15:03
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