Cycles: Pack kernel textures into buffers for OpenCL

Image textures were being packed into a single buffer for OpenCL, which
limited the amount of memory available for images to the size of one
buffer (usually 4gb on AMD hardware). By packing textures into multiple
buffers that limit is removed, while simultaneously reducing the number
of buffers that need to be passed to each kernel.

Benchmarks were within 2%.

Fixes T51554.

Differential Revision: https://developer.blender.org/D2745

1 files changed, 105 insertions, 0 deletions

diff --git a/intern/cycles/device/opencl/memory_manager.h b/intern/cycles/device/opencl/memory_manager.h
new file mode 100644
index 00000000000..3714405d026
--- /dev/null
+++ b/intern/cycles/device/opencl/memory_manager.h
@@ -0,0 +1,105 @@
+/*
+ * Copyright 2011-2017 Blender Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include "device/device.h"
+
+#include "util/util_map.h"
+#include "util/util_vector.h"
+#include "util/util_string.h"
+
+#include "clew.h"
+
+CCL_NAMESPACE_BEGIN
+
+class OpenCLDeviceBase;
+
+class MemoryManager {
+public:
+	static const int NUM_DEVICE_BUFFERS = 8;
+
+	struct BufferDescriptor {
+		uint device_buffer;
+		cl_ulong offset;
+	};
+
+private:
+	struct DeviceBuffer;
+
+	struct Allocation {
+		device_memory *mem;
+
+		DeviceBuffer *device_buffer;
+		size_t size; /* Size of actual allocation, may be larger than requested. */
+
+		BufferDescriptor desc;
+
+		bool needs_copy_to_device;
+
+		Allocation() : mem(NULL), device_buffer(NULL), size(0), needs_copy_to_device(false)
+		{
+		}
+	};
+
+	struct DeviceBuffer {
+		device_memory *buffer;
+		vector<Allocation*> allocations;
+		size_t size; /* Size of all allocations. */
+
+		DeviceBuffer() : buffer(new device_memory), size(0)
+		{
+		}
+
+		~DeviceBuffer() {
+			delete buffer;
+			buffer = NULL;
+		}
+
+		void add_allocation(Allocation& allocation);
+
+		void update_device_memory(OpenCLDeviceBase *device);
+
+		void free(OpenCLDeviceBase *device);
+	};
+
+	OpenCLDeviceBase *device;
+
+	DeviceBuffer device_buffers[NUM_DEVICE_BUFFERS];
+
+	typedef unordered_map<string, Allocation> AllocationsMap;
+	AllocationsMap allocations;
+
+	bool need_update;
+
+	DeviceBuffer* smallest_device_buffer();
+
+public:
+	MemoryManager(OpenCLDeviceBase *device);
+
+	void free(); /* Free all memory. */
+
+	void alloc(const char *name, device_memory& mem);
+	bool free(device_memory& mem);
+
+	BufferDescriptor get_descriptor(string name);
+
+	void update_device_memory();
+	void set_kernel_arg_buffers(cl_kernel kernel, cl_uint *narg);
+};
+
+CCL_NAMESPACE_END
+