From d9a04350b5a618761126b2dcd4170c963f07a037 Mon Sep 17 00:00:00 2001
From: Jeff Gilbert <jgilbert@mozilla.com>
Date: Wed, 7 Nov 2012 11:39:38 +1300
Subject: [PATCH] Bug 797120 - GLContext::CanUploadNonPowerOfTwo() should not
 call AddBoolVarCache() when off the main thread. r=bjacob

---
 gfx/gl/GLContext.cpp       | 31 ++++++++++++++++++++++---------
 gfx/gl/GLContext.h         | 10 ++++++++++
 gfx/thebes/gfxPlatform.cpp |  2 ++
 3 files changed, 34 insertions(+), 9 deletions(-)

diff --git a/gfx/gl/GLContext.cpp b/gfx/gl/GLContext.cpp
index d9f3e27accbc..afb9f895af1b 100644
--- a/gfx/gl/GLContext.cpp
+++ b/gfx/gl/GLContext.cpp
@@ -625,21 +625,34 @@ GLContext::CanUploadSubTextures()
     return true;
 }
 
+bool GLContext::sPowerOfTwoForced = false;
+bool GLContext::sPowerOfTwoPrefCached = false;
+
+void
+GLContext::PlatformStartup()
+{
+  CacheCanUploadNPOT();
+}
+
+void
+GLContext::CacheCanUploadNPOT()
+{
+    MOZ_ASSERT(NS_IsMainThread(), "Can't cache prefs off the main thread.");
+    MOZ_ASSERT(!sPowerOfTwoPrefCached, "Must only call this function once!");
+
+    sPowerOfTwoPrefCached = true;
+    mozilla::Preferences::AddBoolVarCache(&sPowerOfTwoForced,
+                                          "gfx.textures.poweroftwo.force-enabled");
+}
+
 bool
 GLContext::CanUploadNonPowerOfTwo()
 {
+    MOZ_ASSERT(sPowerOfTwoPrefCached);
+
     if (!mWorkAroundDriverBugs)
         return true;
 
-    static bool sPowerOfTwoForced;
-    static bool sPowerOfTwoPrefCached = false;
-
-    if (!sPowerOfTwoPrefCached) {
-        sPowerOfTwoPrefCached = true;
-        mozilla::Preferences::AddBoolVarCache(&sPowerOfTwoForced,
-                                              "gfx.textures.poweroftwo.force-enabled");
-    }
-
     // Some GPUs driver crash when uploading non power of two 565 textures.
     return sPowerOfTwoForced ? false : (Renderer() != RendererAdreno200 &&
                                         Renderer() != RendererAdreno205);
diff --git a/gfx/gl/GLContext.h b/gfx/gl/GLContext.h
index d322d6e644c9..6d14d6d1a5c3 100644
--- a/gfx/gl/GLContext.h
+++ b/gfx/gl/GLContext.h
@@ -744,7 +744,17 @@ public:
     }
 
     bool CanUploadSubTextures();
+
+    static void PlatformStartup();
+
+protected:
+    static bool sPowerOfTwoForced;
+    static bool sPowerOfTwoPrefCached;
+    static void CacheCanUploadNPOT();
+
+public:
     bool CanUploadNonPowerOfTwo();
+
     bool WantsSmallTiles();
     virtual bool HasLockSurface() { return false; }
 
diff --git a/gfx/thebes/gfxPlatform.cpp b/gfx/thebes/gfxPlatform.cpp
index 6ced9c9471fc..abe6eae0275c 100644
--- a/gfx/thebes/gfxPlatform.cpp
+++ b/gfx/thebes/gfxPlatform.cpp
@@ -340,6 +340,8 @@ gfxPlatform::Init()
 
     gPlatform->mWorkAroundDriverBugs = Preferences::GetBool("gfx.work-around-driver-bugs", true);
 
+    mozilla::gl::GLContext::PlatformStartup();
+
 #ifdef MOZ_WIDGET_ANDROID
     // Texture pool init
     mozilla::gl::TexturePoolOGL::Init();