From b2f286fc4aa2e94ffa577edf6e475479246933ca Mon Sep 17 00:00:00 2001
From: Lukasz Jobczyk <lukasz.jobczyk@intel.com>
Date: Thu, 9 Dec 2021 14:09:54 +0000
Subject: [PATCH] Reuse command buffers in L0 command queue

Signed-off-by: Lukasz Jobczyk <lukasz.jobczyk@intel.com>
---
 level_zero/core/source/cmdqueue/cmdqueue.cpp  | 20 ++++++++++++++-----
 .../core/source/cmdqueue/cmdqueue_hw.inl      |  2 +-
 .../core/source/cmdqueue/cmdqueue_imp.h       |  2 +-
 .../sources/cmdqueue/test_cmdqueue_2.cpp      | 16 +++++++++++++++
 4 files changed, 33 insertions(+), 7 deletions(-)

diff --git a/level_zero/core/source/cmdqueue/cmdqueue.cpp b/level_zero/core/source/cmdqueue/cmdqueue.cpp
index b12a4ddfb7..18ff4ddf90 100644
--- a/level_zero/core/source/cmdqueue/cmdqueue.cpp
+++ b/level_zero/core/source/cmdqueue/cmdqueue.cpp
@@ -178,8 +178,18 @@ ze_result_t CommandQueueImp::CommandBufferManager::initialize(Device *device, si
                                          false,
                                          device->getNEODevice()->getDeviceBitfield()};
 
-    buffers[BUFFER_ALLOCATION::FIRST] = device->getNEODevice()->getMemoryManager()->allocateGraphicsMemoryWithProperties(properties);
-    buffers[BUFFER_ALLOCATION::SECOND] = device->getNEODevice()->getMemoryManager()->allocateGraphicsMemoryWithProperties(properties);
+    auto firstBuffer = device->obtainReusableAllocation(alignedSize, NEO::GraphicsAllocation::AllocationType::COMMAND_BUFFER);
+    if (!firstBuffer) {
+        firstBuffer = device->getNEODevice()->getMemoryManager()->allocateGraphicsMemoryWithProperties(properties);
+    }
+
+    auto secondBuffer = device->obtainReusableAllocation(alignedSize, NEO::GraphicsAllocation::AllocationType::COMMAND_BUFFER);
+    if (!secondBuffer) {
+        secondBuffer = device->getNEODevice()->getMemoryManager()->allocateGraphicsMemoryWithProperties(properties);
+    }
+
+    buffers[BUFFER_ALLOCATION::FIRST] = firstBuffer;
+    buffers[BUFFER_ALLOCATION::SECOND] = secondBuffer;
 
     if (!buffers[BUFFER_ALLOCATION::FIRST] || !buffers[BUFFER_ALLOCATION::SECOND]) {
         return ZE_RESULT_ERROR_OUT_OF_DEVICE_MEMORY;
@@ -192,13 +202,13 @@ ze_result_t CommandQueueImp::CommandBufferManager::initialize(Device *device, si
     return ZE_RESULT_SUCCESS;
 }
 
-void CommandQueueImp::CommandBufferManager::destroy(NEO::MemoryManager *memoryManager) {
+void CommandQueueImp::CommandBufferManager::destroy(Device *device) {
     if (buffers[BUFFER_ALLOCATION::FIRST]) {
-        memoryManager->freeGraphicsMemory(buffers[BUFFER_ALLOCATION::FIRST]);
+        device->storeReusableAllocation(*buffers[BUFFER_ALLOCATION::FIRST]);
         buffers[BUFFER_ALLOCATION::FIRST] = nullptr;
     }
     if (buffers[BUFFER_ALLOCATION::SECOND]) {
-        memoryManager->freeGraphicsMemory(buffers[BUFFER_ALLOCATION::SECOND]);
+        device->storeReusableAllocation(*buffers[BUFFER_ALLOCATION::SECOND]);
         buffers[BUFFER_ALLOCATION::SECOND] = nullptr;
     }
 }
diff --git a/level_zero/core/source/cmdqueue/cmdqueue_hw.inl b/level_zero/core/source/cmdqueue/cmdqueue_hw.inl
index 925432e478..df807a7481 100644
--- a/level_zero/core/source/cmdqueue/cmdqueue_hw.inl
+++ b/level_zero/core/source/cmdqueue/cmdqueue_hw.inl
@@ -55,7 +55,7 @@ ze_result_t CommandQueueHw<gfxCoreFamily>::destroy() {
         delete commandStream;
         commandStream = nullptr;
     }
-    buffers.destroy(this->getDevice()->getNEODevice()->getMemoryManager());
+    buffers.destroy(this->getDevice());
     delete this;
     return ZE_RESULT_SUCCESS;
 }
diff --git a/level_zero/core/source/cmdqueue/cmdqueue_imp.h b/level_zero/core/source/cmdqueue/cmdqueue_imp.h
index 31834067e1..1a1a1306e8 100644
--- a/level_zero/core/source/cmdqueue/cmdqueue_imp.h
+++ b/level_zero/core/source/cmdqueue/cmdqueue_imp.h
@@ -36,7 +36,7 @@ struct CommandQueueImp : public CommandQueue {
         };
 
         ze_result_t initialize(Device *device, size_t sizeRequested);
-        void destroy(NEO::MemoryManager *memoryManager);
+        void destroy(Device *device);
         void switchBuffers(NEO::CommandStreamReceiver *csr);
 
         NEO::GraphicsAllocation *getCurrentBufferAllocation() {
diff --git a/level_zero/core/test/unit_tests/sources/cmdqueue/test_cmdqueue_2.cpp b/level_zero/core/test/unit_tests/sources/cmdqueue/test_cmdqueue_2.cpp
index a218283cff..3a7b4e41bc 100644
--- a/level_zero/core/test/unit_tests/sources/cmdqueue/test_cmdqueue_2.cpp
+++ b/level_zero/core/test/unit_tests/sources/cmdqueue/test_cmdqueue_2.cpp
@@ -506,6 +506,22 @@ TEST_F(CommandQueueInitTests, givenMultipleSubDevicesWhenInitializingThenAllocat
     commandQueue->destroy();
 }
 
+TEST_F(CommandQueueInitTests, whenDestroyCommandQueueThenStoreCommandBuffersAsReusableAllocations) {
+    ze_command_queue_desc_t desc = {};
+    auto csr = std::unique_ptr<NEO::CommandStreamReceiver>(neoDevice->createCommandStreamReceiver());
+    csr->setupContext(*neoDevice->getDefaultEngine().osContext);
+
+    ze_result_t returnValue;
+    L0::CommandQueue *commandQueue = CommandQueue::create(productFamily, device, csr.get(), &desc, false, false, returnValue);
+    EXPECT_NE(nullptr, commandQueue);
+    auto deviceImp = static_cast<DeviceImp *>(device);
+    EXPECT_TRUE(deviceImp->allocationsForReuse.peekIsEmpty());
+
+    commandQueue->destroy();
+
+    EXPECT_FALSE(deviceImp->allocationsForReuse.peekIsEmpty());
+}
+
 struct DeviceWithDualStorage : Test<DeviceFixture> {
     void SetUp() override {
         NEO::MockCompilerEnableGuard mock(true);