gl: Fix async shader compiler

- Removes glFinish hack.
- Adds proper server-side synchronization.
- Adds primary context detection to allow worker threads to be identified.

rpcs3/Emu/RSX/GL/GLCompute.h

@@ -50,7 +50,7 @@ namespace gl
 
                 m_program.create();
                 m_program.attach(m_shader);
-                m_program.make();
+                m_program.link();
 
                 compiled = true;
             }

rpcs3/Emu/RSX/GL/GLGSRender.cpp

@@ -76,6 +76,7 @@ void GLGSRender::on_init_thread()
 
 	// Bind primary context to main RSX thread
 	m_frame->set_current(m_context);
+	gl::set_primary_context_thread();
 
 	zcull_ctrl.reset(static_cast<::rsx::reports::ZCULL_control*>(this));
 
@@ -625,6 +626,11 @@ bool GLGSRender::load_program()
 			}
 		}
 	}
+	else
+	{
+		verify(HERE), m_program;
+		m_program->sync();
+	}
 
 	return m_program != nullptr;
 }
@@ -946,13 +952,5 @@ void GLGSRender::on_decompiler_exit()
 
 bool GLGSRender::on_decompiler_task()
 {
-	const auto result = m_prog_buffer.async_update(8);
+	return m_prog_buffer.async_update(8).first;
-	if (result.second)
-	{
-		// TODO: Proper synchronization with renderer
-		// Finish works well enough for now but it is not a proper soulution
-		glFinish();
-	}
-
-	return result.first;
 }

rpcs3/Emu/RSX/GL/GLHelpers.cpp

@@ -11,6 +11,18 @@ namespace gl
 	capabilities g_driver_caps;
 	const fbo screen{};
 
+	thread_local bool tls_primary_context_thread = false;
+
+	void set_primary_context_thread()
+	{
+		tls_primary_context_thread = true;
+	}
+
+	bool is_primary_context_thread()
+	{
+		return tls_primary_context_thread;
+	}
+
 	GLenum draw_mode(rsx::primitive_type in)
 	{
 		switch (in)

rpcs3/Emu/RSX/GL/GLHelpers.h

@@ -86,6 +86,9 @@ namespace gl
 	bool is_primitive_native(rsx::primitive_type in);
 	GLenum draw_mode(rsx::primitive_type in);
 
+	void set_primary_context_thread();
+	bool is_primary_context_thread();
+
 	// Texture helpers
 	std::array<GLenum, 4> apply_swizzle_remap(const std::array<GLenum, 4>& swizzle_remap, const std::pair<std::array<u8, 4>, std::array<u8, 4>>& decoded_remap);
 
@@ -391,6 +394,12 @@ namespace gl
 
 			return signaled;
 		}
+
+		void server_wait_sync() const
+		{
+			verify(HERE), m_value != nullptr;
+			glWaitSync(m_value, 0, GL_TIMEOUT_IGNORED);
+		}
 	};
 
 	template<typename Type, uint BindId, uint GetStateId>
@@ -2533,6 +2542,7 @@ public:
 		class program
 		{
 			GLuint m_id = 0;
+			fence m_fence;
 
 		public:
 			class uniform_t
@@ -2717,6 +2727,15 @@ public:
 
 					rsx_log.fatal("Linkage failed: %s", error_msg);
 				}
+				else
+				{
+					m_fence.create();
+
+					if (!is_primary_context_thread())
+					{
+						glFlush();
+					}
+				}
 			}
 
 			void validate()
@@ -2743,11 +2762,6 @@ public:
 				}
 			}
 
-			void make()
-			{
-				link();
-			}
-
 			uint id() const
 			{
 				return m_id;
@@ -2764,6 +2778,14 @@ public:
 				return m_id != 0;
 			}
 
+			void sync()
+			{
+				if (!m_fence.check_signaled())
+				{
+					m_fence.server_wait_sync();
+				}
+			}
+
 			explicit operator bool() const
 			{
 				return created();

rpcs3/Emu/RSX/GL/GLOverlays.h

@@ -66,7 +66,7 @@ namespace gl
 				program_handle.create();
 				program_handle.attach(vs);
 				program_handle.attach(fs);
-				program_handle.make();
+				program_handle.link();
 
 				fbo.create();
 

rpcs3/Emu/RSX/GL/GLProcTable.h

@@ -217,6 +217,7 @@ OPENGL_PROC(PFNGLBUFFERSTORAGEPROC, BufferStorage);
 // ARB_sync
 OPENGL_PROC(PFNGLFENCESYNCPROC, FenceSync);
 OPENGL_PROC(PFNGLCLIENTWAITSYNCPROC, ClientWaitSync);
+OPENGL_PROC(PFNGLWAITSYNCPROC, WaitSync);
 OPENGL_PROC(PFNGLGETSYNCIVPROC, GetSynciv);
 OPENGL_PROC(PFNGLDELETESYNCPROC, DeleteSync);
 

rpcs3/Emu/RSX/GL/GLProgramBuffer.h

@@ -42,7 +42,7 @@ struct GLTraits
 			.bind_fragment_data_location("ocol1", 1)
 			.bind_fragment_data_location("ocol2", 2)
 			.bind_fragment_data_location("ocol3", 3)
-			.make();
+			.link();
 
 		// Progam locations are guaranteed to not change after linking
 		// Texture locations are simply bound to the TIUs so this can be done once

rpcs3/Emu/RSX/GL/GLTextOut.h

@@ -1,4 +1,4 @@
-#pragma once
+#pragma once
 
 #include "stdafx.h"
 #include "GLHelpers.h"
@@ -63,7 +63,7 @@ namespace gl
 			m_program.create();
 			m_program.attach(m_vs);
 			m_program.attach(m_fs);
-			m_program.make();
+			m_program.link();
 		}
 
 		void load_program(float scale_x, float scale_y, float *offsets, size_t nb_offsets, color4f color)