Round IOSurface sizes to 64 pixels for filter effects.

cc/output/gl_renderer.cc

 // Copyright 2010 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 "cc/output/gl_renderer.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 3924 matching lines @@
   // Perform basic initialization with the screen-sized viewport.
   if (!InitializeRPDQParameters(&params))
     return;
 
   if (!UpdateRPDQWithSkiaFilters(&params))
     return;
 
   // |params.dst_rect| now contain values that reflect a potentially increased
   // size quad.
   gfx::RectF updated_dst_rect = params.dst_rect;
-  *new_bounds = updated_dst_rect;
+
+  // Round the size of the IOSurface to a multiple of 64 pixels. This reduces
+  // memory fragmentation. https://crbug.com/146070. This also allows IOSurfaces
+  // to be more easily reused during a resize operation.
+  uint32_t iosurface_multiple = 64;

[ccameron, 2016/08/15 18:37:06]

May be more concise to do
  updated_dst_rest.set_width(
      MathUtil::UncheckedRoundUp(updated_dst_rest.width(),
      iosurface_multiple));
and same for height, from
https://cs.chromium.org/chromium/src/cc/base/math_util.h?rcl=1471252828&l=112;

[erikchen, 2016/08/15 19:31:57]

Done, although we can't change updated_dst_rect, since it's parameter are still
relevant for setting the viewport.

+  uint32_t iosurface_width = updated_dst_rect.width();
+  if (iosurface_width % iosurface_multiple != 0) {
+    iosurface_width -= iosurface_width % iosurface_multiple;
+    iosurface_width += iosurface_multiple;
+  }
+
+  uint32_t iosurface_height = updated_dst_rect.height();
+  if (iosurface_height % iosurface_multiple != 0) {
+    iosurface_height -= iosurface_height % iosurface_multiple;
+    iosurface_height += iosurface_multiple;
+  }
+
+  *resource = overlay_resource_pool_->AcquireResource(
+      gfx::Size(iosurface_width, iosurface_height), ResourceFormat::RGBA_8888,
+      output_surface_->device_color_space());
+  *new_bounds =
+      gfx::RectF(updated_dst_rect.x(), updated_dst_rect.y(),
+                 (*resource)->size().width(), (*resource)->size().height());
 
   // Calculate new projection and window matrices for a minimally sized viewport
   // using InitializeViewport(). This requires creating a dummy DrawingFrame.
   {
     DrawingFrame frame;
     force_drawing_frame_framebuffer_unflipped_ = true;
     gfx::Rect frame_rect =
         gfx::Rect(0, 0, updated_dst_rect.width(), updated_dst_rect.height());
     InitializeViewport(&frame, frame_rect, frame_rect, frame_rect.size());
     force_drawing_frame_framebuffer_unflipped_ = false;
@@ skipping 19 matching lines @@
     bool clipped = false;
     params.contents_device_transform.FlattenTo2d();
     gfx::QuadF device_layer_quad = MathUtil::MapQuad(
         params.contents_device_transform, SharedGeometryQuad(), &clipped);
     LayerQuad device_layer_edges(device_layer_quad);
     InflateAntiAliasingDistances(device_layer_quad, &device_layer_edges,
                                  params.edge);
   }
 
   // Establish destination texture.
-  *resource = overlay_resource_pool_->AcquireResource(
-      gfx::Size(updated_dst_rect.width(), updated_dst_rect.height()),
-      ResourceFormat::RGBA_8888, output_surface_->device_color_space());
   ResourceProvider::ScopedWriteLockGL destination(resource_provider_,
                                                   (*resource)->id(), false);
   GLuint temp_fbo;
 
   gl_->GenFramebuffers(1, &temp_fbo);
   gl_->BindFramebuffer(GL_FRAMEBUFFER, temp_fbo);
   gl_->FramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
                             destination.target(), destination.texture_id(), 0);
   DCHECK(gl_->CheckFramebufferStatus(GL_FRAMEBUFFER) ==
          GL_FRAMEBUFFER_COMPLETE);
@@ skipping 63 matching lines @@
 
   gl_->ScheduleCALayerSharedStateCHROMIUM(
       ca_layer_overlay->shared_state->opacity, is_clipped, clip_rect,
       sorting_context_id, gl_transform);
   gl_->ScheduleCALayerCHROMIUM(
       texture_id, contents_rect, ca_layer_overlay->background_color,
       ca_layer_overlay->edge_aa_mask, bounds_rect, filter);
 }
 
 }  // namespace cc