Remove limit on number of resources in cc

android_webview/browser/browser_view_renderer.cc

 // Copyright 2014 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 "android_webview/browser/browser_view_renderer.h"
 
 #include "android_webview/browser/browser_view_renderer_client.h"
 #include "android_webview/browser/shared_renderer_state.h"
 #include "android_webview/common/aw_switches.h"
 #include "base/auto_reset.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event_argument.h"
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/stringprintf.h"
 #include "cc/output/compositor_frame.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/content_switches.h"
 #include "gpu/command_buffer/service/gpu_switches.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkPicture.h"
 #include "third_party/skia/include/core/SkPictureRecorder.h"
 #include "ui/gfx/geometry/vector2d_conversions.h"
 
-using content::SynchronousCompositorMemoryPolicy;
-
 namespace android_webview {
 
 namespace {
 
 const int64 kFallbackTickTimeoutInMilliseconds = 100;
 
 // Used to calculate memory allocation. Determined experimentally.
 const size_t kMemoryMultiplier = 20;
 const size_t kBytesPerPixel = 4;
 const size_t kMemoryAllocationStep = 5 * 1024 * 1024;
 uint64 g_memory_override_in_bytes = 0u;
 
-// Used to calculate tile allocation. Determined experimentally.
-const size_t kTileMultiplier = 12;
-const size_t kTileAllocationStep = 20;
-// Use chrome's default tile size, which varies from 256 to 512.
-// Be conservative here and use the smallest tile size possible.
-const size_t kTileArea = 256 * 256;
-
 }  // namespace
 
 // static
 void BrowserViewRenderer::CalculateTileMemoryPolicy() {
   CommandLine* cl = CommandLine::ForCurrentProcess();
 
   // If the value was overridden on the command line, use the specified value.
   bool client_hard_limit_bytes_overridden =
       cl->HasSwitch(switches::kForceGpuMemAvailableMb);
   if (client_hard_limit_bytes_overridden) {
     base::StringToUint64(
         base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
             switches::kForceGpuMemAvailableMb),
         &g_memory_override_in_bytes);
     g_memory_override_in_bytes *= 1024 * 1024;
   }
-
-  // There is no need to limit number of tiles, so use an effectively unlimited
-  // value as the limit.
-  GlobalTileManager::GetInstance()->SetTileLimit(10 * 1000 * 1000);
 }
 
 BrowserViewRenderer::BrowserViewRenderer(
     BrowserViewRendererClient* client,
     SharedRendererState* shared_renderer_state,
     content::WebContents* web_contents,
     const scoped_refptr<base::SingleThreadTaskRunner>& ui_task_runner)
     : client_(client),
       shared_renderer_state_(shared_renderer_state),
       web_contents_(web_contents),
@@ skipping 40 matching lines @@
   // Not urgent enough. TRIM_MEMORY_UI_HIDDEN is treated specially because
   // it does not indicate memory pressure, but merely that the app is
   // backgrounded.
   if (level < TRIM_MEMORY_RUNNING_LOW || level == TRIM_MEMORY_UI_HIDDEN)
     return;
 
   // Do not release resources on view we expect to get DrawGL soon.
   if (level < TRIM_MEMORY_BACKGROUND && visible)
     return;
 
-  // Just set the memory limit to 0 and drop all tiles. This will be reset to
-  // normal levels in the next DrawGL call.
-  SynchronousCompositorMemoryPolicy zero_policy;
-  if (memory_policy_ == zero_policy)
+  // Nothing to drop.
+  if (!compositor_ || !hardware_enabled_)
     return;
 
   TRACE_EVENT0("android_webview", "BrowserViewRenderer::TrimMemory");
-  DCHECK(hardware_enabled_);
-  DCHECK(compositor_);
 
-  RequestMemoryPolicy(zero_policy);
-  EnforceMemoryPolicyImmediately(zero_policy);
-}
-
-SynchronousCompositorMemoryPolicy
-BrowserViewRenderer::CalculateDesiredMemoryPolicy() {
-  SynchronousCompositorMemoryPolicy policy;
-  size_t width = last_on_draw_global_visible_rect_.width();
-  size_t height = last_on_draw_global_visible_rect_.height();
-  policy.bytes_limit = kMemoryMultiplier * kBytesPerPixel * width * height;
-  // Round up to a multiple of kMemoryAllocationStep.
-  policy.bytes_limit =
-      (policy.bytes_limit / kMemoryAllocationStep + 1) * kMemoryAllocationStep;
-
-  if (g_memory_override_in_bytes)
-    policy.bytes_limit = static_cast<size_t>(g_memory_override_in_bytes);
-
-  size_t tiles = width * height * kTileMultiplier / kTileArea;
-  // Round up to a multiple of kTileAllocationStep. The minimum number of tiles
-  // is also kTileAllocationStep.
-  tiles = (tiles / kTileAllocationStep + 1) * kTileAllocationStep;
-  policy.num_resources_limit = tiles;
-  return policy;
-}
-
-// This function updates the cached memory policy in shared renderer state, as
-// well as the tile resource allocation in GlobalTileManager.
-void BrowserViewRenderer::RequestMemoryPolicy(
-    SynchronousCompositorMemoryPolicy& new_policy) {
-  DCHECK(compositor_);
-  GlobalTileManager* manager = GlobalTileManager::GetInstance();
-
-  // The following line will call BrowserViewRenderer::SetMemoryPolicy().
-  manager->RequestTiles(new_policy, tile_manager_key_);
-}
-
-void BrowserViewRenderer::SetMemoryPolicy(
-    SynchronousCompositorMemoryPolicy new_policy,
-    bool effective_immediately) {
-  memory_policy_ = new_policy;
-  if (effective_immediately)
-    EnforceMemoryPolicyImmediately(memory_policy_);
-}
-
-void BrowserViewRenderer::EnforceMemoryPolicyImmediately(
-    SynchronousCompositorMemoryPolicy new_policy) {
-  compositor_->SetMemoryPolicy(new_policy);
+  // Just set the memory limit to 0 and drop all tiles. This will be reset to
+  // normal levels in the next DrawGL call.
+  compositor_->SetMemoryPolicy(0u);

[hush (inactive), 2014/10/24 23:36:37]

do you need to enforce it immediately right here?
what if the next DrawGL never comes?

[boliu, 2014/10/24 23:37:53]

It is enforce it once line below. There's just a huge gap..

[hush (inactive), 2014/10/24 23:49:59]

oops. Yes. Thanks!

   ForceFakeCompositeSW();
 }
 
-SynchronousCompositorMemoryPolicy BrowserViewRenderer::GetMemoryPolicy() const {
-  return memory_policy_;
+size_t BrowserViewRenderer::CalculateDesiredMemoryPolicy() {
+  if (g_memory_override_in_bytes)
+    return static_cast<size_t>(g_memory_override_in_bytes);
+
+  size_t width = last_on_draw_global_visible_rect_.width();
+  size_t height = last_on_draw_global_visible_rect_.height();
+  size_t bytes_limit = kMemoryMultiplier * kBytesPerPixel * width * height;
+  // Round up to a multiple of kMemoryAllocationStep.
+  bytes_limit =
+      (bytes_limit / kMemoryAllocationStep + 1) * kMemoryAllocationStep;
+  return bytes_limit;
 }
 
 bool BrowserViewRenderer::OnDraw(jobject java_canvas,
                                  bool is_hardware_canvas,
                                  const gfx::Vector2d& scroll,
                                  const gfx::Rect& global_visible_rect) {
   last_on_draw_scroll_offset_ = scroll;
   last_on_draw_global_visible_rect_ = global_visible_rect;
 
   if (clear_view_)
@@ skipping 10 matching lines @@
 
 bool BrowserViewRenderer::OnDrawHardware(jobject java_canvas) {
   TRACE_EVENT0("android_webview", "BrowserViewRenderer::OnDrawHardware");
   if (!compositor_)
     return false;
 
   shared_renderer_state_->SetScrollOffset(last_on_draw_scroll_offset_);
 
   if (!hardware_enabled_) {
     hardware_enabled_ = compositor_->InitializeHwDraw();
-    if (hardware_enabled_) {
-      tile_manager_key_ = GlobalTileManager::GetInstance()->PushBack(this);
-    }
   }
   if (!hardware_enabled_)
     return false;
 
   if (last_on_draw_global_visible_rect_.IsEmpty() &&
       parent_draw_constraints_.surface_rect.IsEmpty()) {
     TRACE_EVENT_INSTANT0("android_webview",
                          "EarlyOut_EmptyVisibleRect",
                          TRACE_EVENT_SCOPE_THREAD);
     shared_renderer_state_->SetForceInvalidateOnNextDrawGL(true);
     return client_->RequestDrawGL(java_canvas, false);
   }
 
   ReturnResourceFromParent();
   if (shared_renderer_state_->HasCompositorFrame()) {
     TRACE_EVENT_INSTANT0("android_webview",
                          "EarlyOut_PreviousFrameUnconsumed",
                          TRACE_EVENT_SCOPE_THREAD);
     DidSkipCompositeInDraw();
     return client_->RequestDrawGL(java_canvas, false);
   }
 
   scoped_ptr<cc::CompositorFrame> frame = CompositeHw();
   if (!frame.get())
     return false;
 
   shared_renderer_state_->SetCompositorFrame(frame.Pass(), false);
-  GlobalTileManager::GetInstance()->DidUse(tile_manager_key_);
   return client_->RequestDrawGL(java_canvas, false);
 }
 
 scoped_ptr<cc::CompositorFrame> BrowserViewRenderer::CompositeHw() {
-  SynchronousCompositorMemoryPolicy new_policy = CalculateDesiredMemoryPolicy();
-  RequestMemoryPolicy(new_policy);
-  compositor_->SetMemoryPolicy(memory_policy_);
+  compositor_->SetMemoryPolicy(CalculateDesiredMemoryPolicy());
 
   parent_draw_constraints_ = shared_renderer_state_->ParentDrawConstraints();
   gfx::Size surface_size(width_, height_);
   gfx::Rect viewport(surface_size);
   gfx::Rect clip = viewport;
   gfx::Transform transform_for_tile_priority =
       parent_draw_constraints_.transform;
 
   // If the WebView is on a layer, WebView does not know what transform is
   // applied onto the layer so global visible rect does not make sense here.
@@ skipping 177 matching lines @@
 }
 
 void BrowserViewRenderer::ReleaseHardware() {
   DCHECK(hardware_enabled_);
   ReturnUnusedResource(shared_renderer_state_->PassCompositorFrame());
   ReturnResourceFromParent();
   DCHECK(shared_renderer_state_->ReturnedResourcesEmpty());
 
   if (compositor_) {
     compositor_->ReleaseHwDraw();
-    SynchronousCompositorMemoryPolicy zero_policy;
-    RequestMemoryPolicy(zero_policy);
   }
 
   hardware_enabled_ = false;
-  GlobalTileManager::GetInstance()->Remove(tile_manager_key_);
 }
 
 bool BrowserViewRenderer::IsVisible() const {
   // Ignore |window_visible_| if |attached_to_window_| is false.
   return view_visible_ && (!attached_to_window_ || window_visible_);
 }
 
 gfx::Rect BrowserViewRenderer::GetScreenRect() const {
   return gfx::Rect(client_->GetLocationOnScreen(), gfx::Size(width_, height_));
 }
 
 void BrowserViewRenderer::DidInitializeCompositor(
     content::SynchronousCompositor* compositor) {
   TRACE_EVENT0("android_webview",
                "BrowserViewRenderer::DidInitializeCompositor");
   DCHECK(compositor);
   DCHECK(!compositor_);
   compositor_ = compositor;
 }
 
 void BrowserViewRenderer::DidDestroyCompositor(
     content::SynchronousCompositor* compositor) {
   TRACE_EVENT0("android_webview", "BrowserViewRenderer::DidDestroyCompositor");
   DCHECK(compositor_);
-  SynchronousCompositorMemoryPolicy zero_policy;
-  if (hardware_enabled_) {
-    RequestMemoryPolicy(zero_policy);
-  }
-  DCHECK(memory_policy_ == zero_policy);
   compositor_ = NULL;
 }
 
 void BrowserViewRenderer::SetContinuousInvalidate(bool invalidate) {
   if (compositor_needs_continuous_invalidate_ == invalidate)
     return;
 
   TRACE_EVENT_INSTANT1("android_webview",
                        "BrowserViewRenderer::SetContinuousInvalidate",
                        TRACE_EVENT_SCOPE_THREAD,
@@ skipping 310 matching lines @@
   base::StringAppendF(&str,
                       "overscroll_rounding_error_: %s ",
                       overscroll_rounding_error_.ToString().c_str());
   base::StringAppendF(
       &str, "on_new_picture_enable: %d ", on_new_picture_enable_);
   base::StringAppendF(&str, "clear_view: %d ", clear_view_);
   return str;
 }
 
 }  // namespace android_webview