[UR] Change IPC handle get function to return the original pointer (#20490)

This commit makes the UR interfaces implementing urIPCGetMemHandleExp
return the exact memory pointer from UMF instead of copying the handle
data. This is done as the exact pointer is expected to be passed when
calling umfPutIPCHandle in the urIPCPutMemHandleExp interface.

---------

Signed-off-by: Larsen, Steffen <[email protected]>

Author: steffenlarsen

unified-runtime/include/ur_api.h

@@ -36,8 +36,8 @@ params:
     - type: void *
       name: pMem
       desc: "[in] pointer to device USM memory"
-    - type: void*
-      name: pIPCMemHandleData
+    - type: void**
+      name: ppIPCMemHandleData
       desc: "[out][optional] a pointer to the IPC memory handle data"
     - type: size_t*
       name: pIPCMemHandleDataSizeRet
@@ -47,7 +47,7 @@ returns:
     - $X_RESULT_ERROR_INVALID_NULL_HANDLE:
       - "`NULL == hContext`"
     - $X_RESULT_ERROR_INVALID_NULL_POINTER:
-      - "`NULL == pIPCMemHandleData`"
+      - "`NULL == ppIPCMemHandleData`"
       - "`NULL == pIPCMemHandleDataSizeRet`"
     - $X_RESULT_ERROR_OUT_OF_HOST_MEMORY
     - $X_RESULT_ERROR_OUT_OF_RESOURCES

unified-runtime/include/ur_ddi.h

@@ -592,28 +592,25 @@ CUsurfObject SurfaceMem::getSurface(const ur_device_handle_t Device) {
 }
 
 UR_APIEXPORT ur_result_t UR_APICALL
-urIPCGetMemHandleExp(ur_context_handle_t, void *pMem, void *pIPCMemHandleData,
+urIPCGetMemHandleExp(ur_context_handle_t, void *pMem, void **ppIPCMemHandleData,
                      size_t *pIPCMemHandleDataSizeRet) {
   umf_memory_pool_handle_t umfPool;
   auto urRet = umf::umf2urResult(umfPoolByPtr(pMem, &umfPool));
   if (urRet)
     return urRet;
 
   // Fast path for returning the size of the handle only.
-  if (!pIPCMemHandleData)
+  if (!ppIPCMemHandleData)
     return umf::umf2urResult(
         umfPoolGetIPCHandleSize(umfPool, pIPCMemHandleDataSizeRet));
 
   size_t fallbackUMFHandleSize = 0;
   size_t *umfHandleSize = pIPCMemHandleDataSizeRet != nullptr
                               ? pIPCMemHandleDataSizeRet
                               : &fallbackUMFHandleSize;
-  umf_ipc_handle_t umfHandle;
-  urRet = umf::umf2urResult(umfGetIPCHandle(pMem, &umfHandle, umfHandleSize));
-  if (urRet)
-    return urRet;
-  std::memcpy(pIPCMemHandleData, umfHandle, *umfHandleSize);
-  return UR_RESULT_SUCCESS;
+  return umf::umf2urResult(umfGetIPCHandle(
+      pMem, reinterpret_cast<umf_ipc_handle_t *>(ppIPCMemHandleData),
+      umfHandleSize));
 }
 
 UR_APIEXPORT ur_result_t UR_APICALL

unified-runtime/include/ur_print.hpp

@@ -642,7 +642,7 @@ hipSurfaceObject_t SurfaceMem::getSurface(const ur_device_handle_t Device) {
 }
 
 UR_APIEXPORT ur_result_t UR_APICALL urIPCGetMemHandleExp(ur_context_handle_t,
-                                                         void *, void *,
+                                                         void *, void **,
                                                          size_t *) {
   return UR_RESULT_ERROR_UNSUPPORTED_FEATURE;
 }

unified-runtime/scripts/core/exp-inter-process-communication.yml

@@ -1953,28 +1953,25 @@ ur_result_t urEnqueueWriteHostPipe(
 }
 
 ur_result_t urIPCGetMemHandleExp(ur_context_handle_t, void *pMem,
-                                 void *pIPCMemHandleData,
+                                 void **ppIPCMemHandleData,
                                  size_t *pIPCMemHandleDataSizeRet) {
   umf_memory_pool_handle_t umfPool;
   auto urRet = umf::umf2urResult(umfPoolByPtr(pMem, &umfPool));
   if (urRet)
     return urRet;
 
   // Fast path for returning the size of the handle only.
-  if (!pIPCMemHandleData)
+  if (!ppIPCMemHandleData)
     return umf::umf2urResult(
         umfPoolGetIPCHandleSize(umfPool, pIPCMemHandleDataSizeRet));
 
   size_t fallbackUMFHandleSize = 0;
   size_t *umfHandleSize = pIPCMemHandleDataSizeRet != nullptr
                               ? pIPCMemHandleDataSizeRet
                               : &fallbackUMFHandleSize;
-  umf_ipc_handle_t umfHandle;
-  urRet = umf::umf2urResult(umfGetIPCHandle(pMem, &umfHandle, umfHandleSize));
-  if (urRet)
-    return urRet;
-  std::memcpy(pIPCMemHandleData, umfHandle, *umfHandleSize);
-  return UR_RESULT_SUCCESS;
+  return umf::umf2urResult(umfGetIPCHandle(
+      pMem, reinterpret_cast<umf_ipc_handle_t *>(ppIPCMemHandleData),
+      umfHandleSize));
 }
 
 ur_result_t urIPCPutMemHandleExp(ur_context_handle_t, void *pIPCMemHandleData) {

unified-runtime/source/adapters/cuda/memory.cpp

@@ -782,28 +782,25 @@ ur_result_t urMemImageGetInfo(ur_mem_handle_t /*hMemory*/,
 }
 
 ur_result_t urIPCGetMemHandleExp(ur_context_handle_t, void *pMem,
-                                 void *pIPCMemHandleData,
+                                 void **ppIPCMemHandleData,
                                  size_t *pIPCMemHandleDataSizeRet) {
   umf_memory_pool_handle_t umfPool;
   auto urRet = umf::umf2urResult(umfPoolByPtr(pMem, &umfPool));
   if (urRet)
     return urRet;
 
   // Fast path for returning the size of the handle only.
-  if (!pIPCMemHandleData)
+  if (!ppIPCMemHandleData)
     return umf::umf2urResult(
         umfPoolGetIPCHandleSize(umfPool, pIPCMemHandleDataSizeRet));
 
   size_t fallbackUMFHandleSize = 0;
   size_t *umfHandleSize = pIPCMemHandleDataSizeRet != nullptr
                               ? pIPCMemHandleDataSizeRet
                               : &fallbackUMFHandleSize;
-  umf_ipc_handle_t umfHandle;
-  urRet = umf::umf2urResult(umfGetIPCHandle(pMem, &umfHandle, umfHandleSize));
-  if (urRet)
-    return urRet;
-  std::memcpy(pIPCMemHandleData, umfHandle, *umfHandleSize);
-  return UR_RESULT_SUCCESS;
+  return umf::umf2urResult(umfGetIPCHandle(
+      pMem, reinterpret_cast<umf_ipc_handle_t *>(ppIPCMemHandleData),
+      umfHandleSize));
 }
 
 ur_result_t urIPCPutMemHandleExp(ur_context_handle_t, void *pIPCMemHandleData) {