refactor: add debug flag to control delay after waiting for paging fence on cpu

Related-To: NEO-8395

Signed-off-by: Zbigniew Zdanowicz <zbigniew.zdanowicz@intel.com>

shared/source/debug_settings/debug_variables_base.inl

@@ -97,6 +97,7 @@ DECLARE_DEBUG_VARIABLE(std::string, OverridePlatformName, std::string("unk"), "O
 DECLARE_DEBUG_VARIABLE(std::string, WddmResidencyLoggerOutputDirectory, std::string("unk"), "Selects non-default output directory for Wddm Residency logger file")
 DECLARE_DEBUG_VARIABLE(int64_t, OverrideMultiStoragePlacement, -1, "Place memory only in selected tiles indicated by bit mask; ignore when -1")
 DECLARE_DEBUG_VARIABLE(int64_t, ForceCompressionDisabledForCompressedBlitCopies, -1, "If compression is required, set AUX_CCS_E, but force CompressionEnable filed; 0 should result in uncompressed read/write; values = -1: default, 0: disabled, 1: enabled")
+DECLARE_DEBUG_VARIABLE(int64_t, WddmPagingFenceCpuWaitDelayTime, 0, "Amount of microseconds after waitng for paging fence on CPU")
 DECLARE_DEBUG_VARIABLE(int32_t, ForceL1Caching, -1, "Program L1 cache policy for surface state and stateless accesses; values = -1: default, 0: disable, 1: enable")
 DECLARE_DEBUG_VARIABLE(int32_t, ForceAuxTranslationEnabled, -1, "Require AUX translation for kernels; values = -1: default, 0: disabled, 1: enabled")
 DECLARE_DEBUG_VARIABLE(int32_t, EnableExperimentalCommandBuffer, 0, "Inject experimental command buffer")

shared/source/os_interface/windows/wddm/wddm.cpp

@@ -73,6 +73,7 @@ Wddm::Wddm(std::unique_ptr<HwDeviceIdWddm> &&hwDeviceIdIn, RootDeviceEnvironment
     forceCheck = true;
 #endif
     checkDeviceState = (DebugManager.flags.EnableDeviceStateVerification.get() != -1) ? DebugManager.flags.EnableDeviceStateVerification.get() : forceCheck;
+    pagingFenceDelayTime = DebugManager.flags.WddmPagingFenceCpuWaitDelayTime.get();
 }
 
 Wddm::~Wddm() {
@@ -1264,12 +1265,27 @@ void Wddm::virtualFree(void *ptr, size_t size) {
 
 void Wddm::waitOnPagingFenceFromCpu() {
     perfLogStartWaitTime(residencyLogger.get(), currentPagingFenceValue);
-    while (currentPagingFenceValue > *getPagingFenceAddress())
-        perfLogResidencyEnteredWait(residencyLogger.get());
+    if (currentPagingFenceValue > *getPagingFenceAddress()) {
+        while (currentPagingFenceValue > *getPagingFenceAddress()) {
+            perfLogResidencyEnteredWait(residencyLogger.get());
+        }
+        if (pagingFenceDelayTime > 0) {
+            delayPagingFenceFromCpu(pagingFenceDelayTime);
+        }
+    }
 
     perfLogResidencyWaitPagingeFenceLog(residencyLogger.get(), *getPagingFenceAddress(), false);
 }
 
+void Wddm::delayPagingFenceFromCpu(int64_t delayTime) {
+    int64_t timeDiff = 0u;
+    auto waitStartTime = std::chrono::high_resolution_clock::now();
+    while (timeDiff < delayTime) {
+        auto currentTime = std::chrono::high_resolution_clock::now();
+        timeDiff = std::chrono::duration_cast<std::chrono::microseconds>(currentTime - waitStartTime).count();
+    }
+}
+
 void Wddm::updatePagingFenceValue(uint64_t newPagingFenceValue) {
     NEO::MultiThreadHelpers::interlockedMax(currentPagingFenceValue, newPagingFenceValue);
 }

shared/source/os_interface/windows/wddm/wddm.h

@@ -171,6 +171,7 @@ class Wddm : public DriverModel {
         return gmmMemory.get();
     }
     MOCKABLE_VIRTUAL void waitOnPagingFenceFromCpu();
+    MOCKABLE_VIRTUAL void delayPagingFenceFromCpu(int64_t delayTime);
 
     void setGmmInputArgs(void *args) override;
 
@@ -270,6 +271,7 @@ class Wddm : public DriverModel {
     RootDeviceEnvironment &rootDeviceEnvironment;
 
     uint64_t *pagingFenceAddress = nullptr;
+    int64_t pagingFenceDelayTime = 0;
 
     uintptr_t maximumApplicationAddress = 0;
     uintptr_t minAddress = 0;

shared/test/common/mocks/mock_wddm.cpp

@@ -318,6 +318,11 @@ void WddmMock::waitOnPagingFenceFromCpu() {
     Wddm::waitOnPagingFenceFromCpu();
 }
 
+void WddmMock::delayPagingFenceFromCpu(int64_t delayTime) {
+    delayPagingFenceFromCpuResult.called++;
+    Wddm::delayPagingFenceFromCpu(delayTime);
+}
+
 void WddmMock::createPagingFenceLogger() {
     if (callBaseCreatePagingLogger) {
         Wddm::createPagingFenceLogger();

shared/test/common/mocks/mock_wddm.h

@@ -47,6 +47,7 @@ class WddmMock : public Wddm {
     using Wddm::mapGpuVirtualAddress;
     using Wddm::minAddress;
     using Wddm::pagingFenceAddress;
+    using Wddm::pagingFenceDelayTime;
     using Wddm::pagingQueue;
     using Wddm::platformSupportsEvictIfNecessary;
     using Wddm::populateAdditionalAdapterInfoOptions;
@@ -98,6 +99,7 @@ class WddmMock : public Wddm {
     PLATFORM *getGfxPlatform() { return gfxPlatform.get(); }
     uint64_t *getPagingFenceAddress() override;
     void waitOnPagingFenceFromCpu() override;
+    void delayPagingFenceFromCpu(int64_t delayTime) override;
     void createPagingFenceLogger() override;
     bool verifyAdapterLuid(LUID adapterLuid) const override {
         if (callBaseVerifyAdapterLuid) {
@@ -163,6 +165,7 @@ class WddmMock : public Wddm {
     WddmMockHelpers::CallResult reserveGpuVirtualAddressResult;
     WddmMockHelpers::CallResult waitOnPagingFenceFromCpuResult;
     WddmMockHelpers::CallResult setAllocationPriorityResult;
+    WddmMockHelpers::CallResult delayPagingFenceFromCpuResult;
 
     StackVec<WddmMockHelpers::MakeResidentCall, 2> makeResidentParamsPassed{};
     bool makeResidentStatus = true;

shared/test/common/test_files/igdrcl.config

@@ -71,6 +71,7 @@ ForceAuxTranslationEnabled = -1
 DisableTimestampPacketOptimizations = 0
 DisableCachingForStatefulBufferAccess = 0
 PrintDebugSettings = 0
+WddmPagingFenceCpuWaitDelayTime = 0
 UsePipeControlMultiKernelEventSync = -1
 PrintDebugMessages = 0
 DumpZEBin = 0

shared/test/unit_test/os_interface/windows/wddm20_tests.cpp

@@ -1727,3 +1727,41 @@ TEST_F(WddmTestWithMockGdiDll, givenNonZeroMaxDualSubSlicesSupportedWhenQueryAda
     EXPECT_EQ(expectedMaxDSS, wddm->getGtSysInfo()->MaxDualSubSlicesSupported);
     EXPECT_NE(maxSS / 2, wddm->getGtSysInfo()->MaxDualSubSlicesSupported);
 }
+
+struct WddmPagingFenceTest : public WddmTest {
+    void SetUp() override {
+        DebugManager.flags.WddmPagingFenceCpuWaitDelayTime.set(WddmPagingFenceTest::defaultTestDelay);
+        WddmTest::SetUp();
+    }
+
+    DebugManagerStateRestore dbgRestore;
+    static constexpr int64_t defaultTestDelay = 10;
+};
+
+TEST_F(WddmPagingFenceTest, givenPagingFenceDelayNonZeroWhenCurrentPagingFenceValueNotGreaterThanPagingFenceObjectThenNoPagingFenceDelayCalled) {
+    EXPECT_EQ(WddmPagingFenceTest::defaultTestDelay, wddm->pagingFenceDelayTime);
+    wddm->mockPagingFence = 0u;
+    wddm->currentPagingFenceValue = 1u;
+
+    wddm->waitOnPagingFenceFromCpu();
+    EXPECT_EQ(0u, wddm->delayPagingFenceFromCpuResult.called);
+}
+
+TEST_F(WddmPagingFenceTest, givenPagingFenceDelayNonZeroWhenCurrentPagingFenceValueGreaterThanPagingFenceObjectThenPagingFenceDelayCalled) {
+    EXPECT_EQ(WddmPagingFenceTest::defaultTestDelay, wddm->pagingFenceDelayTime);
+    wddm->mockPagingFence = 0u;
+    wddm->currentPagingFenceValue = 2u;
+
+    wddm->waitOnPagingFenceFromCpu();
+    EXPECT_EQ(1u, wddm->delayPagingFenceFromCpuResult.called);
+}
+
+TEST_F(WddmPagingFenceTest, givenPagingFenceDelayZeroWhenCurrentPagingFenceValueGreaterThanPagingFenceObjectThenNoPagingFenceDelayCalled) {
+    EXPECT_EQ(WddmPagingFenceTest::defaultTestDelay, wddm->pagingFenceDelayTime);
+    wddm->mockPagingFence = 0u;
+    wddm->currentPagingFenceValue = 3u;
+    wddm->pagingFenceDelayTime = 0;
+
+    wddm->waitOnPagingFenceFromCpu();
+    EXPECT_EQ(0u, wddm->delayPagingFenceFromCpuResult.called);
+}