From 2166f7cbccc88c0678505ac1e78b23a759c5ca7c Mon Sep 17 00:00:00 2001
From: John Falkowski <john.falkowski@intel.com>
Date: Thu, 31 Aug 2023 06:14:14 +0000
Subject: [PATCH] fix: Disable 1-tile chunking dev mem

Disable chunking for device memory allocation if only 1Tile

Related-To: NEO-8098

Signed-off-by: John Falkowski <john.falkowski@intel.com>
---
 .../os_interface/linux/drm_memory_manager.cpp |  6 +++--
 .../linux/drm_memory_manager_tests.cpp        | 26 +++++++++++++++++++
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/shared/source/os_interface/linux/drm_memory_manager.cpp b/shared/source/os_interface/linux/drm_memory_manager.cpp
index 3eadb85c55..14dc64d55d 100644
--- a/shared/source/os_interface/linux/drm_memory_manager.cpp
+++ b/shared/source/os_interface/linux/drm_memory_manager.cpp
@@ -1881,9 +1881,11 @@ bool DrmMemoryManager::createDrmAllocation(Drm *drm, DrmAllocation *allocation,
         uint32_t numOfChunks = DebugManager.flags.NumberOfBOChunks.get();
         size_t chunkingSize = boTotalChunkSize / numOfChunks;
 
-        // Dont chunk for sizes less than chunkThreshold
+        // Do not chunk for sizes less than chunkThreshold
+        // Do not chunk for single tile device memory
         if (boTotalChunkSize >= drm->getMinimalSizeForChunking() &&
-            !(chunkingSize & (MemoryConstants::chunkThreshold - 1))) {
+            !(chunkingSize & (MemoryConstants::chunkThreshold - 1)) &&
+            (allocation->storageInfo.subDeviceBitfield.count() > 1)) {
 
             handles = 1;
             allocation->resizeBufferObjects(handles);
diff --git a/shared/test/unit_test/os_interface/linux/drm_memory_manager_tests.cpp b/shared/test/unit_test/os_interface/linux/drm_memory_manager_tests.cpp
index 5cfef53146..3dce29b7c7 100644
--- a/shared/test/unit_test/os_interface/linux/drm_memory_manager_tests.cpp
+++ b/shared/test/unit_test/os_interface/linux/drm_memory_manager_tests.cpp
@@ -5319,6 +5319,7 @@ TEST_F(DrmMemoryManagerWithLocalMemoryAndExplicitExpectationsTest,
     allocData.type = AllocationType::BUFFER;
     allocData.rootDeviceIndex = rootDeviceIndex;
     allocData.storageInfo.memoryBanks = 0b11;
+    allocData.storageInfo.subDeviceBitfield = 0b11;
 
     auto allocation = memoryManager->allocateGraphicsMemoryInDevicePool(allocData, status);
     EXPECT_NE(nullptr, allocation);
@@ -5351,6 +5352,29 @@ TEST_F(DrmMemoryManagerWithLocalMemoryAndExplicitExpectationsTest,
     memoryManager->freeGraphicsMemory(allocation);
 }
 
+TEST_F(DrmMemoryManagerWithLocalMemoryAndExplicitExpectationsTest,
+       givenDeviceMemoryAllocationWithChunkingModeSetToDeviceAndOnlyOneTileThenChunkingIsNotUsed) {
+    VariableBackup<bool> backupChunkingCallParent{&mock->getChunkingAvailableCall.callParent, false};
+    VariableBackup<bool> backupChunkingReturnValue{&mock->getChunkingAvailableCall.returnValue, true};
+    VariableBackup<bool> backupChunkingModeCallParent{&mock->getChunkingModeCall.callParent, false};
+    VariableBackup<uint32_t> backupChunkingModeReturnValue{&mock->getChunkingModeCall.returnValue, 0x2};
+
+    MemoryManager::AllocationStatus status = MemoryManager::AllocationStatus::Success;
+    AllocationData allocData;
+    allocData.allFlags = 0;
+    allocData.size = MemoryConstants::pageSize2M;
+    allocData.type = AllocationType::BUFFER;
+    allocData.rootDeviceIndex = rootDeviceIndex;
+    allocData.storageInfo.memoryBanks = 0b11;
+    allocData.storageInfo.subDeviceBitfield = 0b01;
+
+    auto allocation = memoryManager->allocateGraphicsMemoryInDevicePool(allocData, status);
+    EXPECT_NE(nullptr, allocation);
+    EXPECT_FALSE(allocation->storageInfo.isChunked);
+
+    memoryManager->freeGraphicsMemory(allocation);
+}
+
 TEST_F(DrmMemoryManagerWithLocalMemoryAndExplicitExpectationsTest,
        givenDeviceMemoryAllocationWithChunkingModeSetToDeviceThenChunkingIsUsed) {
     VariableBackup<bool> backupChunkingCallParent{&mock->getChunkingAvailableCall.callParent, false};
@@ -5365,6 +5389,7 @@ TEST_F(DrmMemoryManagerWithLocalMemoryAndExplicitExpectationsTest,
     allocData.type = AllocationType::BUFFER;
     allocData.rootDeviceIndex = rootDeviceIndex;
     allocData.storageInfo.memoryBanks = 0b11;
+    allocData.storageInfo.subDeviceBitfield = 0b11;
 
     auto allocation = memoryManager->allocateGraphicsMemoryInDevicePool(allocData, status);
     EXPECT_NE(nullptr, allocation);
@@ -5460,6 +5485,7 @@ TEST_F(DrmMemoryManagerWithLocalMemoryAndExplicitExpectationsTest,
     allocData.type = AllocationType::BUFFER;
     allocData.rootDeviceIndex = rootDeviceIndex;
     allocData.storageInfo.memoryBanks = 0b11;
+    allocData.storageInfo.subDeviceBitfield = 0b11;
     static_cast<MockedMemoryInfo *>(mock->getMemoryInfo())->failOnCreateGemExtWithMultipleRegions = true;
 
     auto allocation = memoryManager->allocateGraphicsMemoryInDevicePool(allocData, status);