Merge branch 'master' into stable

1 files changed, 398 insertions, 0 deletions

diff --git a/Source/Core/VideoBackends/OGL/StreamBuffer.cpp b/Source/Core/VideoBackends/OGL/StreamBuffer.cpp
new file mode 100644
index 0000000000..0caa1e4589
--- /dev/null
+++ b/Source/Core/VideoBackends/OGL/StreamBuffer.cpp
@@ -0,0 +1,398 @@
+// Copyright 2013 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#include "Common/MemoryUtil.h"
+
+#include "VideoBackends/OGL/GLUtil.h"
+#include "VideoBackends/OGL/Render.h"
+#include "VideoBackends/OGL/StreamBuffer.h"
+
+#include "VideoCommon/DriverDetails.h"
+#include "VideoCommon/OnScreenDisplay.h"
+
+namespace OGL
+{
+
+// moved out of constructor, so m_buffer is allowed to be const
+static u32 genBuffer()
+{
+	u32 id;
+	glGenBuffers(1, &id);
+	return id;
+}
+
+StreamBuffer::StreamBuffer(u32 type, u32 size)
+: m_buffer(genBuffer()), m_buffertype(type), m_size(ROUND_UP_POW2(size)), m_bit_per_slot(IntLog2(ROUND_UP_POW2(size) / SYNC_POINTS))
+{
+	m_iterator = 0;
+	m_used_iterator = 0;
+	m_free_iterator = 0;
+}
+
+
+StreamBuffer::~StreamBuffer()
+{
+	glDeleteBuffers(1, &m_buffer);
+}
+
+/* Shared synchronization code for ring buffers
+ *
+ * The next three functions are to create/delete/use the OpenGL synchronization.
+ * ARB_sync (OpenGL 3.2) is used and required.
+ *
+ * To reduce overhead, the complete buffer is splitted up into SYNC_POINTS chunks.
+ * For each of this chunks, there is a fence which checks if this chunk is still in use.
+ *
+ * As our API allows to alloc more memory then it has to use, we have to catch how much is already written.
+ *
+ * m_iterator      - writing position
+ * m_free_iterator - last position checked if free
+ * m_used_iterator - last position known to be written
+ *
+ * So on alloc, we have to wait for all slots between m_free_iterator and m_iterator (and set m_free_iterator to m_iterator afterwards).
+ *
+ * We also assume that this buffer is accessed by the GPU between the Unmap and Map function,
+ * so we may create the fences on the start of mapping.
+ * Some here, new fences for the chunks between m_used_iterator and m_iterator (also update m_used_iterator).
+ *
+ * As ring buffers have an ugly behavior on rollover, have fun to read this code ;)
+ */
+
+void StreamBuffer::CreateFences()
+{
+	for (int i=0; i<SYNC_POINTS; i++)
+	{
+		fences[i] = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
+	}
+}
+void StreamBuffer::DeleteFences()
+{
+	for (int i = SLOT(m_free_iterator) + 1; i < SYNC_POINTS; i++)
+	{
+		glDeleteSync(fences[i]);
+	}
+	for (int i = 0; i < SLOT(m_iterator); i++)
+	{
+		glDeleteSync(fences[i]);
+	}
+}
+void StreamBuffer::AllocMemory(u32 size)
+{
+	// insert waiting slots for used memory
+	for (int i = SLOT(m_used_iterator); i < SLOT(m_iterator); i++)
+	{
+		fences[i] = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
+	}
+	m_used_iterator = m_iterator;
+
+	// wait for new slots to end of buffer
+	for (int i = SLOT(m_free_iterator) + 1; i <= SLOT(m_iterator + size) && i < SYNC_POINTS; i++)
+	{
+		glClientWaitSync(fences[i], GL_SYNC_FLUSH_COMMANDS_BIT, GL_TIMEOUT_IGNORED);
+		glDeleteSync(fences[i]);
+	}
+	m_free_iterator = m_iterator + size;
+
+	// if buffer is full
+	if (m_iterator + size >= m_size)
+	{
+		// insert waiting slots in unused space at the end of the buffer
+		for (int i = SLOT(m_used_iterator); i < SYNC_POINTS; i++)
+		{
+			fences[i] = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
+		}
+
+		// move to the start
+		m_used_iterator = m_iterator = 0; // offset 0 is always aligned
+
+		// wait for space at the start
+		for (int i = 0; i <= SLOT(m_iterator + size); i++)
+		{
+			glClientWaitSync(fences[i], GL_SYNC_FLUSH_COMMANDS_BIT, GL_TIMEOUT_IGNORED);
+			glDeleteSync(fences[i]);
+		}
+		m_free_iterator = m_iterator + size;
+	}
+}
+
+/* The usual way to stream data to the GPU.
+ * Described here: https://www.opengl.org/wiki/Buffer_Object_Streaming#Unsynchronized_buffer_mapping
+ * Just do unsync appends until the buffer is full.
+ * When it's full, orphan (alloc a new buffer and free the old one)
+ *
+ * As reallocation is an overhead, this method isn't as fast as it is known to be.
+ */
+class MapAndOrphan : public StreamBuffer
+{
+public:
+	MapAndOrphan(u32 type, u32 size) : StreamBuffer(type, size)
+	{
+		glBindBuffer(m_buffertype, m_buffer);
+		glBufferData(m_buffertype, m_size, nullptr, GL_STREAM_DRAW);
+	}
+
+	~MapAndOrphan()
+	{
+	}
+
+	std::pair<u8*, u32> Map(u32 size) override
+	{
+		if (m_iterator + size >= m_size)
+		{
+			glBufferData(m_buffertype, m_size, nullptr, GL_STREAM_DRAW);
+			m_iterator = 0;
+		}
+		u8* pointer = (u8*)glMapBufferRange(m_buffertype, m_iterator, size,
+			GL_MAP_WRITE_BIT | GL_MAP_FLUSH_EXPLICIT_BIT | GL_MAP_UNSYNCHRONIZED_BIT);
+		return std::make_pair(pointer, m_iterator);
+	}
+
+	void Unmap(u32 used_size) override
+	{
+		glFlushMappedBufferRange(m_buffertype, 0, used_size);
+		glUnmapBuffer(m_buffertype);
+		m_iterator += used_size;
+	}
+};
+
+/* A modified streaming way without reallocation
+ * This one fixes the reallocation overhead of the MapAndOrphan one.
+ * So it alloc a ring buffer on initialization.
+ * But with this limited resource, we have to care about the CPU-GPU distance.
+ * Else this fifo may overflow.
+ * So we had traded orphan vs syncing.
+ */
+class MapAndSync : public StreamBuffer
+{
+public:
+	MapAndSync(u32 type, u32 size) : StreamBuffer(type, size)
+	{
+		CreateFences();
+		glBindBuffer(m_buffertype, m_buffer);
+		glBufferData(m_buffertype, m_size, nullptr, GL_STREAM_DRAW);
+	}
+
+	~MapAndSync()
+	{
+		DeleteFences();
+	}
+
+	std::pair<u8*, u32> Map(u32 size) override
+	{
+		AllocMemory(size);
+		u8* pointer = (u8*)glMapBufferRange(m_buffertype, m_iterator, size,
+			GL_MAP_WRITE_BIT | GL_MAP_FLUSH_EXPLICIT_BIT | GL_MAP_UNSYNCHRONIZED_BIT);
+		return std::make_pair(pointer, m_iterator);
+	}
+
+	void Unmap(u32 used_size) override
+	{
+		glFlushMappedBufferRange(m_buffertype, 0, used_size);
+		glUnmapBuffer(m_buffertype);
+		m_iterator += used_size;
+	}
+};
+
+/* Streaming fifo without mapping overhead.
+ * This one usually requires ARB_buffer_storage (OpenGL 4.4).
+ * And is usually not available on OpenGL3 GPUs.
+ *
+ * ARB_buffer_storage allows us to render from a mapped buffer.
+ * So we map it persistently in the initialization.
+ *
+ * Unsync mapping sounds like an easy task, but it isn't for threaded drivers.
+ * So every mapping on current close-source driver _will_ end in
+ * at least a round trip time between two threads.
+ *
+ * As persistently mapped buffer can't use orphaning, we also have to sync.
+ */
+class BufferStorage : public StreamBuffer
+{
+public:
+	BufferStorage(u32 type, u32 size) : StreamBuffer(type, size)
+	{
+		CreateFences();
+		glBindBuffer(m_buffertype, m_buffer);
+
+		// PERSISTANT_BIT to make sure that the buffer can be used while mapped
+		// COHERENT_BIT is set so we don't have to use a MemoryBarrier on write
+		// CLIENT_STORAGE_BIT is set since we access the buffer more frequently on the client side then server side
+		glBufferStorage(m_buffertype, m_size, nullptr,
+			GL_MAP_WRITE_BIT | GL_MAP_PERSISTENT_BIT);
+		m_pointer = (u8*)glMapBufferRange(m_buffertype, 0, m_size,
+			GL_MAP_WRITE_BIT | GL_MAP_PERSISTENT_BIT | GL_MAP_FLUSH_EXPLICIT_BIT);
+	}
+
+	~BufferStorage()
+	{
+		DeleteFences();
+		glUnmapBuffer(m_buffertype);
+		glBindBuffer(m_buffertype, 0);
+	}
+
+	std::pair<u8*, u32> Map(u32 size) override
+	{
+		AllocMemory(size);
+		return std::make_pair(m_pointer + m_iterator, m_iterator);
+	}
+
+	void Unmap(u32 used_size) override
+	{
+		glFlushMappedBufferRange(m_buffertype, m_iterator, used_size);
+		m_iterator += used_size;
+	}
+
+	u8* m_pointer;
+};
+
+/* --- AMD only ---
+ * Another streaming fifo without mapping overhead.
+ * As we can't orphan without mapping, we have to sync.
+ *
+ * This one uses AMD_pinned_memory which is available on all AMD GPUs.
+ * OpenGL 4.4 drivers should use BufferStorage.
+ */
+class PinnedMemory : public StreamBuffer
+{
+public:
+	PinnedMemory(u32 type, u32 size) : StreamBuffer(type, size)
+	{
+		CreateFences();
+		m_pointer = (u8*)AllocateAlignedMemory(ROUND_UP(m_size,ALIGN_PINNED_MEMORY), ALIGN_PINNED_MEMORY );
+		glBindBuffer(GL_EXTERNAL_VIRTUAL_MEMORY_BUFFER_AMD, m_buffer);
+		glBufferData(GL_EXTERNAL_VIRTUAL_MEMORY_BUFFER_AMD, ROUND_UP(m_size,ALIGN_PINNED_MEMORY), m_pointer, GL_STREAM_COPY);
+		glBindBuffer(GL_EXTERNAL_VIRTUAL_MEMORY_BUFFER_AMD, 0);
+		glBindBuffer(m_buffertype, m_buffer);
+	}
+
+	~PinnedMemory()
+	{
+		DeleteFences();
+		glBindBuffer(m_buffertype, 0);
+		glFinish(); // ogl pipeline must be flushed, else this buffer can be in use
+		FreeAlignedMemory(m_pointer);
+		m_pointer = nullptr;
+	}
+
+	std::pair<u8*, u32> Map(u32 size) override
+	{
+		AllocMemory(size);
+		return std::make_pair(m_pointer + m_iterator, m_iterator);
+	}
+
+	void Unmap(u32 used_size) override
+	{
+		m_iterator += used_size;
+	}
+
+	u8* m_pointer;
+	static const u32 ALIGN_PINNED_MEMORY = 4096;
+};
+
+/* Fifo based on the glBufferSubData call.
+ * As everything must be copied before glBufferSubData returns,
+ * an additional memcpy in the driver will be done.
+ * So this is a huge overhead, only use it if required.
+ */
+class BufferSubData : public StreamBuffer
+{
+public:
+	BufferSubData(u32 type, u32 size) : StreamBuffer(type, size)
+	{
+		glBindBuffer(m_buffertype, m_buffer);
+		glBufferData(m_buffertype, size, nullptr, GL_STATIC_DRAW);
+		m_pointer = new u8[m_size];
+	}
+
+	~BufferSubData()
+	{
+		delete [] m_pointer;
+	}
+
+	std::pair<u8*, u32> Map(u32 size) override
+	{
+		return std::make_pair(m_pointer, 0);
+	}
+
+	void Unmap(u32 used_size) override
+	{
+		glBufferSubData(m_buffertype, 0, used_size, m_pointer);
+	}
+
+	u8* m_pointer;
+};
+
+/* Fifo based on the glBufferData call.
+ * Some trashy drivers stall in BufferSubData.
+ * So here we use glBufferData, which realloc this buffer every time.
+ * This may avoid stalls, but it is a bigger overhead than BufferSubData.
+ */
+class BufferData : public StreamBuffer
+{
+public:
+	BufferData(u32 type, u32 size) : StreamBuffer(type, size)
+	{
+		glBindBuffer(m_buffertype, m_buffer);
+		m_pointer = new u8[m_size];
+	}
+
+	~BufferData()
+	{
+		delete [] m_pointer;
+	}
+
+	std::pair<u8*, u32> Map(u32 size) override
+	{
+		return std::make_pair(m_pointer, 0);
+	}
+
+	void Unmap(u32 used_size) override
+	{
+		glBufferData(m_buffertype, used_size, m_pointer, GL_STREAM_DRAW);
+	}
+
+	u8* m_pointer;
+};
+
+// choose best streaming library based on the supported extensions and known issues
+StreamBuffer* StreamBuffer::Create(u32 type, u32 size)
+{
+	// without basevertex support, only streaming methods whith uploads everything to zero works fine:
+	if (!g_ogl_config.bSupportsGLBaseVertex)
+	{
+		if (!DriverDetails::HasBug(DriverDetails::BUG_BROKENBUFFERSTREAM))
+			return new BufferSubData(type, size);
+
+		// BufferData is by far the worst way, only use it if needed
+		return new BufferData(type, size);
+	}
+
+	// Prefer the syncing buffers over the orphaning one
+	if (g_ogl_config.bSupportsGLSync)
+	{
+		// pinned memory is much faster than buffer storage on AMD cards
+		if (g_ogl_config.bSupportsGLPinnedMemory &&
+			!(DriverDetails::HasBug(DriverDetails::BUG_BROKENPINNEDMEMORY) && type == GL_ELEMENT_ARRAY_BUFFER))
+			return new PinnedMemory(type, size);
+
+		// buffer storage works well in most situations
+		if (g_ogl_config.bSupportsGLBufferStorage &&
+			!(DriverDetails::HasBug(DriverDetails::BUG_BROKENBUFFERSTORAGE) && type == GL_ARRAY_BUFFER) &&
+			!(DriverDetails::HasBug(DriverDetails::BUG_INTELBROKENBUFFERSTORAGE) && type == GL_ELEMENT_ARRAY_BUFFER))
+			return new BufferStorage(type, size);
+
+		// don't fall back to MapAnd* for Nvidia drivers
+		if (DriverDetails::HasBug(DriverDetails::BUG_BROKENUNSYNCMAPPING))
+			return new BufferSubData(type, size);
+
+		// mapping fallback
+		if (g_ogl_config.bSupportsGLSync)
+			return new MapAndSync(type, size);
+	}
+
+	// default fallback, should work everywhere, but isn't the best way to do this job
+	return new MapAndOrphan(type, size);
+}
+
+}