Drop frontbuffers with ui-use-gpu-process, synchronized with browser, decoupled from backbuffer dro…

content/common/gpu/texture_image_transport_surface.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/common/gpu/texture_image_transport_surface.h"
 
 #include "base/command_line.h"
 #include "content/common/gpu/gpu_channel.h"
 #include "content/common/gpu/gpu_channel_manager.h"
 #include "content/common/gpu/gpu_messages.h"
@@ skipping 51 matching lines @@
 
 TextureImageTransportSurface::TextureImageTransportSurface(
     GpuChannelManager* manager,
     GpuCommandBufferStub* stub,
     const gfx::GLSurfaceHandle& handle)
       : fbo_id_(0),
         front_(0),
         stub_destroyed_(false),
         backbuffer_suggested_allocation_(true),
         frontbuffer_suggested_allocation_(true),
+        frontbuffer_is_protected_(true),
         handle_(handle),
         parent_stub_(NULL) {
   helper_.reset(new ImageTransportHelper(this,
                                          manager,
                                          stub,
                                          gfx::kNullPluginWindow));
 
   stub->AddDestructionObserver(this);
 }
 
@@ skipping 93 matching lines @@
 }
 
 void TextureImageTransportSurface::SetBackbufferAllocation(bool allocation) {
   if (backbuffer_suggested_allocation_ == allocation)
      return;
   backbuffer_suggested_allocation_ = allocation;
 
   if (!helper_->MakeCurrent())
     return;
 
-  if (backbuffer_suggested_allocation_)
+  if (backbuffer_suggested_allocation_) {
+    DCHECK(!textures_[back()].info->service_id() ||
+           !textures_[back()].sent_to_client);
     CreateBackTexture(textures_[back()].size);
-  else
-    ReleaseBackTexture();
+  } else {
+    ReleaseTexture(back());
+  }
 }
 
 void TextureImageTransportSurface::SetFrontbufferAllocation(bool allocation) {
   if (frontbuffer_suggested_allocation_ == allocation)
     return;
   frontbuffer_suggested_allocation_ = allocation;
+  AdjustFrontBufferAllocation();
+}
+
+void TextureImageTransportSurface::AdjustFrontBufferAllocation() {
+  if (!helper_->MakeCurrent())
+    return;
+
+  if (!frontbuffer_suggested_allocation_ && !frontbuffer_is_protected_ &&
+      textures_[front()].info->service_id()) {
+    ReleaseTexture(front());
+    if (textures_[front()].sent_to_client) {
+      GpuHostMsg_AcceleratedSurfaceRelease_Params params;
+      params.identifier = textures_[front()].client_id;
+      helper_->SendAcceleratedSurfaceRelease(params);
+      textures_[front()].sent_to_client = false;
+    }
+  }
 }
 
 void* TextureImageTransportSurface::GetShareHandle() {
   return GetHandle();
 }
 
 void* TextureImageTransportSurface::GetDisplay() {
   return parent_stub_ ? parent_stub_->surface()->GetDisplay() : NULL;
 }
 
@@ skipping 20 matching lines @@
       CHECK_GL_ERROR();
       fbo_id_ = 0;
     }
 
     stub_destroyed_ = true;
   }
 }
 
 bool TextureImageTransportSurface::SwapBuffers() {
   DCHECK(backbuffer_suggested_allocation_);
-  if (!frontbuffer_suggested_allocation_)
+  if (!frontbuffer_suggested_allocation_ || !frontbuffer_is_protected_)
     return true;
   if (!parent_stub_) {
     LOG(ERROR) << "SwapBuffers failed because no parent stub.";
     return false;
   }
 
   glFlush();
   front_ = back();
-  previous_damage_rect_ = gfx::Rect(textures_[front_].size);
+  previous_damage_rect_ = gfx::Rect(textures_[front()].size);
 
-  DCHECK(textures_[front_].client_id != 0);
+  DCHECK(textures_[front()].client_id != 0);
 
   GpuHostMsg_AcceleratedSurfaceBuffersSwapped_Params params;
-  params.surface_handle = textures_[front_].client_id;
+  params.surface_handle = textures_[front()].client_id;
   helper_->SendAcceleratedSurfaceBuffersSwapped(params);
   helper_->SetScheduled(false);
   return true;
 }
 
 bool TextureImageTransportSurface::PostSubBuffer(
     int x, int y, int width, int height) {
   DCHECK(backbuffer_suggested_allocation_);
-  if (!frontbuffer_suggested_allocation_)
+  DCHECK(textures_[back()].info->service_id());
+  if (!frontbuffer_suggested_allocation_ || !frontbuffer_is_protected_)
     return true;
   // If we are recreating the frontbuffer with this swap, make sure we are
   // drawing a full frame.
-  DCHECK(textures_[front_].info->service_id() ||
+  DCHECK(textures_[front()].info->service_id() ||
          (!x && !y && gfx::Size(width, height) == textures_[back()].size));
   if (!parent_stub_) {
     LOG(ERROR) << "PostSubBuffer failed because no parent stub.";
     return false;
   }
 
-  DCHECK(textures_[back()].info);
-  int back_texture_service_id = textures_[back()].info->service_id();
-
-  DCHECK(textures_[front_].info);
-  int front_texture_service_id = textures_[front_].info->service_id();
-
-  gfx::Size expected_size = textures_[back()].size;
-  bool surfaces_same_size = textures_[front_].size == expected_size;
-
   const gfx::Rect new_damage_rect(x, y, width, height);
 
   // An empty damage rect is a successful no-op.
   if (new_damage_rect.IsEmpty())
     return true;
 
+  int back_texture_service_id = textures_[back()].info->service_id();
+  int front_texture_service_id = textures_[front()].info->service_id();
+
+  gfx::Size expected_size = textures_[back()].size;
+  bool surfaces_same_size = textures_[front()].size == expected_size;
+
   if (surfaces_same_size) {
     std::vector<gfx::Rect> regions_to_copy;
     GetRegionsToCopy(previous_damage_rect_, new_damage_rect, &regions_to_copy);
 
     ScopedFrameBufferBinder fbo_binder(fbo_id_);
     glFramebufferTexture2DEXT(GL_FRAMEBUFFER,
         GL_COLOR_ATTACHMENT0,
         GL_TEXTURE_2D,
         front_texture_service_id,
         0);
     ScopedTextureBinder texture_binder(back_texture_service_id);
 
     for (size_t i = 0; i < regions_to_copy.size(); ++i) {
       const gfx::Rect& region_to_copy = regions_to_copy[i];
       if (!region_to_copy.IsEmpty()) {
         glCopyTexSubImage2D(GL_TEXTURE_2D, 0, region_to_copy.x(),
             region_to_copy.y(), region_to_copy.x(), region_to_copy.y(),
             region_to_copy.width(), region_to_copy.height());
       }
     }
   } else {
     DCHECK(new_damage_rect == gfx::Rect(expected_size));
   }
 
   glFlush();
   front_ = back();
+  previous_damage_rect_ = new_damage_rect;
+
+  DCHECK(textures_[front()].client_id);
 
   GpuHostMsg_AcceleratedSurfacePostSubBuffer_Params params;
-  params.surface_handle = textures_[front_].client_id;
+  params.surface_handle = textures_[front()].client_id;
   params.x = x;
   params.y = y;
   params.width = width;
   params.height = height;
   helper_->SendAcceleratedSurfacePostSubBuffer(params);
   helper_->SetScheduled(false);
-
-  previous_damage_rect_ = new_damage_rect;
   return true;
 }
 
 std::string TextureImageTransportSurface::GetExtensions() {
   std::string extensions = gfx::GLSurface::GetExtensions();
   extensions += extensions.empty() ? "" : " ";
   extensions += "GL_CHROMIUM_front_buffer_cached ";
   extensions += "GL_CHROMIUM_post_sub_buffer";
   return extensions;
 }
 
 gfx::Size TextureImageTransportSurface::GetSize() {
   return textures_[back()].size;
 }
 
 void* TextureImageTransportSurface::GetHandle() {
   return parent_stub_ ? parent_stub_->surface()->GetHandle() : NULL;
 }
 
 
 void TextureImageTransportSurface::OnNewSurfaceACK(
     uint64 surface_handle, TransportDIB::Handle /*shm_handle*/) {
 }
 
+void TextureImageTransportSurface::OnSetFrontSurfaceIsProtected(
+    bool is_protected) {
+  if (frontbuffer_is_protected_ == is_protected)
+    return;
+  frontbuffer_is_protected_ = is_protected;
+  AdjustFrontBufferAllocation();
+
+  // If surface is set to protected, and we haven't actually released it yet,
+  // we can set the ui surface handle now just by sending a swap message.
+  if (is_protected && textures_[front()].info->service_id() &&
+      textures_[front()].sent_to_client) {
+    // TODO: safe to send swapbuffers when using postsubbuffers usually?

[piman, 2012/06/11 21:32:24]

Yes, it's always safe. A Swap is essentially a Post will full damage.

[mmocny, 2012/06/12 18:26:18]

Done.

+    GpuHostMsg_AcceleratedSurfaceBuffersSwapped_Params params;
+    params.surface_handle = textures_[front()].client_id;
+    helper_->SendAcceleratedSurfaceBuffersSwapped(params);
+    // TODO: can we do this without descheduling the channel?
+    helper_->SetScheduled(false);
+  }
+}
+
 void TextureImageTransportSurface::OnBuffersSwappedACK() {
   if (helper_->MakeCurrent()) {
-    if (textures_[front_].size != textures_[back()].size) {
-      CreateBackTexture(textures_[front_].size);
+    if (textures_[front()].size != textures_[back()].size ||

[piman, 2012/06/11 21:32:24]

We should be very careful here.

When restoring the tab, it's possible that the tab has changed size in the mean
time.

On one hand, the browser will send a IsProtected(true), upon which the GPU
process will send a Swap, and that will come back here.
On the other hand, the renderer may have started a new frame, with the new size,
i.e. it will have resized the back buffer.

Depending on timing, when we get here, it's possible that
textures_[front()].size (the old size) != textures_[back()].size (the new size).
However, at this point we do not want to recreate the back texture (it would
resize it to the wrong size, and lose all the rendering that has been done up to
now).

Maybe the best is to keep a flag or something in OnSetFrontSurfaceIsProtected,
so that we tag the Swap as "special", so that we treat is specially here. That
can even help you avoid unscheduling. Just beware of multiple IsProtected in ABA
cases (i.e that flag maybe should be a counter, but special care may need to be
taken if the "real" swap is coming from the renderer before we got an ack from
the "fake" swap).

[mmocny, 2012/06/11 21:45:09]

Okay, this sounds like it could be potentially hairy.
I'll get something in with counters like you suggest and can evaluate the
concerns once things are cleaned up.

On 2012/06/11 21:32:24, piman wrote:

[mmocny, 2012/06/12 18:26:18]

I got around this issue, as well as having other benefits, by just taking a
SwapBuffers with a "require_ack" bool.

Then, the ui knows this is a special swap type, and the gpu process doesn't need
to do anything fancy in the ACK handler.

On 2012/06/11 21:45:09, mmocny wrote:

+        !textures_[back()].info->service_id() ||
+        !textures_[back()].sent_to_client) {
+      // We may get an ACK from a stale swap just to reschedule.  In that case,
+      // we may not have a backbuffer suggestion and should not recreate one.
+      if (backbuffer_suggested_allocation_)
+        CreateBackTexture(textures_[front()].size);
     } else {
       AttachBackTextureToFBO();
     }
   }
 
   // Even if MakeCurrent fails, schedule anyway, to trigger the lost context
   // logic.
   helper_->SetScheduled(true);
 }
 
 void TextureImageTransportSurface::OnPostSubBufferACK() {
   OnBuffersSwappedACK();
 }
 
 void TextureImageTransportSurface::OnResizeViewACK() {
   NOTREACHED();
 }
 
-void TextureImageTransportSurface::ReleaseBackTexture() {
+void TextureImageTransportSurface::ReleaseTexture(int id) {
   if (!parent_stub_)
     return;
-  TextureInfo* info = textures_[back()].info;
+  Texture& texture = textures_[id];
+  TextureInfo* info = texture.info;
   DCHECK(info);
 
   GLuint service_id = info->service_id();
   if (!service_id)
     return;
   info->SetServiceId(0);
 
   {
     ScopedFrameBufferBinder fbo_binder(fbo_id_);
     glDeleteTextures(1, &service_id);
   }
   glFlush();
   CHECK_GL_ERROR();
 }
 
 void TextureImageTransportSurface::CreateBackTexture(const gfx::Size& size) {
   if (!parent_stub_)
     return;
   Texture& texture = textures_[back()];
   TextureInfo* info = texture.info;
   DCHECK(info);
 
   GLuint service_id = info->service_id();
 
-  if (service_id && texture.size == size)
+  if (service_id && texture.size == size && texture.sent_to_client)
     return;
 
   if (!service_id) {
     glGenTextures(1, &service_id);
     info->SetServiceId(service_id);
   }
 
   if (size != texture.size) {
     texture.size = size;
     TextureManager* texture_manager =
@@ skipping 30 matching lines @@
   params.width = size.width();
   params.height = size.height();
   params.surface_handle = texture.client_id;
   helper_->SendAcceleratedSurfaceNew(params);
   texture.sent_to_client = true;
 }
 
 void TextureImageTransportSurface::AttachBackTextureToFBO() {
   if (!parent_stub_)
     return;
-  DCHECK(textures_[back()].info);
+  TextureInfo* info = textures_[back()].info;
+  DCHECK(info);
 
   ScopedFrameBufferBinder fbo_binder(fbo_id_);
   glFramebufferTexture2DEXT(GL_FRAMEBUFFER,
       GL_COLOR_ATTACHMENT0,
       GL_TEXTURE_2D,
-      textures_[back()].info->service_id(),
+      info->service_id(),
       0);
   glFlush();
   CHECK_GL_ERROR();
 
 #ifndef NDEBUG
   GLenum status = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER);
   if (status != GL_FRAMEBUFFER_COMPLETE) {
     DLOG(ERROR) << "Framebuffer incomplete.";
   }
 #endif
 }
 
 void TextureImageTransportSurface::ReleaseParentStub() {
   DCHECK(parent_stub_);
   parent_stub_->RemoveDestructionObserver(this);
   for (int i = 0; i < 2; ++i) {
     Texture& texture = textures_[i];
     texture.info = NULL;
     if (!texture.sent_to_client)
       continue;
     GpuHostMsg_AcceleratedSurfaceRelease_Params params;
     params.identifier = texture.client_id;
     helper_->SendAcceleratedSurfaceRelease(params);
   }
   parent_stub_ = NULL;
 }