Merge pull request #1864 from zhaomaosu/buffer-migration

[DeviceSanitizer] Support data migration for memory buffer

Author: Omar Ahmed

source/loader/layers/sanitizer/asan_buffer.cpp

@@ -75,12 +75,14 @@ ur_result_t MemBuffer::getHandle(ur_device_handle_t Device, char *&Handle) {
         return UR_RESULT_SUCCESS;
     }
 
+    std::scoped_lock<ur_shared_mutex> Guard(Mutex);
     auto &Allocation = Allocations[Device];
+    ur_result_t URes = UR_RESULT_SUCCESS;
     if (!Allocation) {
         ur_usm_desc_t USMDesc{};
         USMDesc.align = getAlignment();
         ur_usm_pool_handle_t Pool{};
-        ur_result_t URes = getContext()->interceptor->allocateMemory(
+        URes = getContext()->interceptor->allocateMemory(
             Context, Device, &USMDesc, Pool, Size, AllocType::MEM_BUFFER,
             ur_cast<void **>(&Allocation));
         if (URes != UR_RESULT_SUCCESS) {
@@ -105,7 +107,60 @@ ur_result_t MemBuffer::getHandle(ur_device_handle_t Device, char *&Handle) {
 
     Handle = Allocation;
 
-    return UR_RESULT_SUCCESS;
+    if (!LastSyncedDevice.hDevice) {
+        LastSyncedDevice = MemBuffer::Device_t{Device, Handle};
+        return URes;
+    }
+
+    // If the device required to allocate memory is not the previous one, we
+    // need to do data migration.
+    if (Device != LastSyncedDevice.hDevice) {
+        auto &HostAllocation = Allocations[nullptr];
+        if (!HostAllocation) {
+            ur_usm_desc_t USMDesc{};
+            USMDesc.align = getAlignment();
+            ur_usm_pool_handle_t Pool{};
+            URes = getContext()->interceptor->allocateMemory(
+                Context, nullptr, &USMDesc, Pool, Size, AllocType::HOST_USM,
+                ur_cast<void **>(&HostAllocation));
+            if (URes != UR_RESULT_SUCCESS) {
+                getContext()->logger.error("Failed to allocate {} bytes host "
+                                           "USM for buffer {} migration",
+                                           Size, this);
+                return URes;
+            }
+        }
+
+        // Copy data from last synced device to host
+        {
+            ManagedQueue Queue(Context, LastSyncedDevice.hDevice);
+            URes = getContext()->urDdiTable.Enqueue.pfnUSMMemcpy(
+                Queue, true, HostAllocation, LastSyncedDevice.MemHandle, Size,
+                0, nullptr, nullptr);
+            if (URes != UR_RESULT_SUCCESS) {
+                getContext()->logger.error(
+                    "Failed to migrate memory buffer data");
+                return URes;
+            }
+        }
+
+        // Sync data back to device
+        {
+            ManagedQueue Queue(Context, Device);
+            URes = getContext()->urDdiTable.Enqueue.pfnUSMMemcpy(
+                Queue, true, Allocation, HostAllocation, Size, 0, nullptr,
+                nullptr);
+            if (URes != UR_RESULT_SUCCESS) {
+                getContext()->logger.error(
+                    "Failed to migrate memory buffer data");
+                return URes;
+            }
+        }
+    }
+
+    LastSyncedDevice = MemBuffer::Device_t{Device, Handle};
+
+    return URes;
 }
 
 ur_result_t MemBuffer::free() {

source/loader/layers/sanitizer/asan_buffer.hpp

@@ -48,6 +48,12 @@ struct MemBuffer {
 
     ur_context_handle_t Context;
 
+    struct Device_t {
+        ur_device_handle_t hDevice;
+        char *MemHandle;
+    };
+    Device_t LastSyncedDevice{};
+
     size_t Size;
 
     char *HostPtr{};