gpu: Add EGL fence support.

ui/gl/gl_fence.cc

Index: ui/gl/gl_fence.cc
diff --git a/ui/gl/gl_fence.cc b/ui/gl/gl_fence.cc
index 9a40ec2a8b652f11135be687c46aeef9a22216fb..15b21a9fa9919f33aaa8fa204047823d0265de6b 100644
--- a/ui/gl/gl_fence.cc
+++ b/ui/gl/gl_fence.cc
@@ -32,6 +32,10 @@ class GLFenceNVFence: public gfx::GLFence {
     return !!glTestFenceNV(fence_);
   }
 
+  virtual void ClientWait() {
+    NOTIMPLEMENTED();

[apatrick_chromium, 2013/06/18 22:15:01]

glFinishFenceNV(fence_);

[epenner, 2013/06/18 22:37:25]

Done.

+  }
+
  private:
   virtual ~GLFenceNVFence() {
     glDeleteFencesNV(1, &fence_);
@@ -62,6 +66,10 @@ class GLFenceARBSync: public gfx::GLFence {
     return length == 1 && value == GL_SIGNALED;
   }
 
+  virtual void ClientWait() {
+    NOTIMPLEMENTED();

[apatrick_chromium, 2013/06/18 22:15:01]

glClientWaitSyncARB(sync_, SYNC_FLUSH_COMMANDS_BIT, TIMEOUT_IGNORED);

[epenner, 2013/06/18 22:37:25]

Done. Note there is no ARB, and added GL_ to constants.

+  }
+
  private:
   virtual ~GLFenceARBSync() {
     glDeleteSync(sync_);
@@ -70,6 +78,36 @@ class GLFenceARBSync: public gfx::GLFence {
   GLsync sync_;
 };
 
+class EglFenceSync : public gfx::GLFence {

[apatrick_chromium, 2013/06/18 22:15:01]

We've been using "EGL" (all caps) everywhere else.

[epenner, 2013/06/18 22:37:25]

Done.

+ public:
+  EglFenceSync() {
+    sync_ = eglCreateSyncKHR(eglGetCurrentDisplay(),

[apatrick_chromium, 2013/06/18 22:15:01]

nit: make first arg display_ and move the statement below up.

[epenner, 2013/06/18 22:37:25]

Done.

+                             EGL_SYNC_FENCE_KHR, NULL);
+    display_ = eglGetCurrentDisplay();
+  }
+
+  virtual bool HasCompleted() OVERRIDE {
+    EGLint value = 0;
+    eglGetSyncAttribKHR(display_, sync_, EGL_SYNC_STATUS_KHR, &value);
+    DCHECK(value == EGL_SIGNALED_KHR || value == EGL_UNSIGNALED_KHR);
+    return !value || value == EGL_SIGNALED_KHR;
+  }
+
+  virtual void ClientWait() OVERRIDE {
+    EGLint flags = EGL_SYNC_FLUSH_COMMANDS_BIT_KHR;
+    EGLTimeKHR time = EGL_FOREVER_KHR;
+    eglClientWaitSyncKHR(display_, sync_, flags, time);
+  }
+
+ private:
+  virtual ~EglFenceSync() {
+    eglDestroySyncKHR(display_, sync_);
+  }
+
+  EGLSyncKHR sync_;
+  EGLDisplay display_;
+};
+
 }  // namespace
 
 namespace gfx {
@@ -82,7 +120,9 @@ GLFence::~GLFence() {
 
 // static
 GLFence* GLFence::Create() {
-  if (gfx::g_driver_gl.ext.b_GL_NV_fence) {
+  if (gfx::g_driver_egl.ext.b_EGL_KHR_fence_sync) {
+    return new EglFenceSync();
+  } else if (gfx::g_driver_gl.ext.b_GL_NV_fence) {
     return new GLFenceNVFence();
   } else if (gfx::g_driver_gl.ext.b_GL_ARB_sync) {
     return new GLFenceARBSync();