From: Steinar H. Gunderson <sgunderson@bigfoot.com>
Date: Mon, 18 Apr 2016 21:12:05 +0000 (+0200)
Subject: Put a global lock around glFenceSync/glDeleteSync calls, to workaround apitrace bug... 
X-Git-Tag: 1.3.0~79
X-Git-Url: https://git.sesse.net/?a=commitdiff_plain;h=10ff4d7e0cba7d0c5d11317aa5e11679382d3cfe;hp=16c71cac0d5c81e84271222d1ed0c501fe723d56;p=nageru

Put a global lock around glFenceSync/glDeleteSync calls, to workaround apitrace bug #446. (Replaying Nageru calls using apitrace can be very useful, and it should not have any appreciable performance impact in practice.)
---

diff --git a/mixer.cpp b/mixer.cpp
index 8c95f38..3d4cccb 100644
--- a/mixer.cpp
+++ b/mixer.cpp
@@ -1205,3 +1205,5 @@ void Mixer::OutputChannel::set_frame_ready_callback(Mixer::new_frame_ready_callb
 	new_frame_ready_callback = callback;
 	has_new_frame_ready_callback = true;
 }
+
+mutex RefCountedGLsync::fence_lock;
diff --git a/ref_counted_gl_sync.h b/ref_counted_gl_sync.h
index 8b6a8af..8b6db68 100644
--- a/ref_counted_gl_sync.h
+++ b/ref_counted_gl_sync.h
@@ -8,6 +8,7 @@
 
 #include <epoxy/gl.h>
 #include <memory>
+#include <mutex>
 
 typedef std::shared_ptr<__GLsync> RefCountedGLsyncBase;
 
@@ -16,7 +17,23 @@ public:
 	RefCountedGLsync() {}
 
 	RefCountedGLsync(GLenum condition, GLbitfield flags) 
-		: RefCountedGLsyncBase(glFenceSync(condition, flags), glDeleteSync) {}
+		: RefCountedGLsyncBase(locked_glFenceSync(condition, flags), glDeleteSync) {}
+
+private:
+	// These are to work around apitrace bug #446.
+	static GLsync locked_glFenceSync(GLenum condition, GLbitfield flags)
+	{
+		std::lock_guard<std::mutex> lock(fence_lock);
+		return glFenceSync(condition, flags);
+	}
+
+	static void locked_glDeleteSync(GLsync sync)
+	{
+		std::lock_guard<std::mutex> lock(fence_lock);
+		glDeleteSync(sync);
+	}
+
+	static std::mutex fence_lock;
 };
 
 #endif  // !defined(_REF_COUNTED_GL_SYNC_H)