Make GLES2Implementation use a larger chunk size for mapping functions.

gpu/command_buffer/client/mapped_memory.cc

 // Copyright (c) 2011 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 <algorithm>
 #include <functional>
 
 #include "../client/mapped_memory.h"
 #include "../client/cmd_buffer_helper.h"
 
 namespace gpu {
 namespace {
 void DeleteMemoryChunk(MemoryChunk* chunk) {
   delete chunk;
 }
 }
 
 MemoryChunk::MemoryChunk(
     int32 shm_id, gpu::Buffer shm, CommandBufferHelper* helper)
     : shm_id_(shm_id),
       shm_(shm),
       allocator_(shm.size, helper, shm.ptr) {
 }
 
 MappedMemoryManager::MappedMemoryManager(CommandBufferHelper* helper)
-    : helper_(helper) {
+    : chunk_size_multiple_(1),
+      helper_(helper) {
 }
 
 MappedMemoryManager::~MappedMemoryManager() {
   std::for_each(chunks_.begin(),
                 chunks_.end(),
                 std::pointer_to_unary_function<MemoryChunk*, void>(
                     DeleteMemoryChunk));
 }
 
 void* MappedMemoryManager::Alloc(
     unsigned int size, int32* shm_id, unsigned int* shm_offset) {
   GPU_DCHECK(shm_id);
   GPU_DCHECK(shm_offset);
   // See if any of the chucks can satisfy this request.
   for (size_t ii = 0; ii < chunks_.size(); ++ii) {
     MemoryChunk* chunk = chunks_[ii];
     chunk->FreeUnused();
     if (chunk->GetLargestFreeSizeWithoutWaiting() >= size) {
       void* mem = chunk->Alloc(size);
       GPU_DCHECK(mem);
       *shm_id = chunk->shm_id();
       *shm_offset = chunk->GetOffset(mem);
       return mem;
     }
   }
 
   // Make a new chunk to satisfy the request.
   CommandBuffer* cmd_buf = helper_->command_buffer();
-  int32 id = cmd_buf->CreateTransferBuffer(size, -1);
+  unsigned int chunk_size =
+      ((size + chunk_size_multiple_ - 1) / chunk_size_multiple_) *
+      chunk_size_multiple_;
+  int32 id = cmd_buf->CreateTransferBuffer(chunk_size, -1);
   if (id == -1) {
     return NULL;
   }
   gpu::Buffer shm = cmd_buf->GetTransferBuffer(id);
   MemoryChunk* mc = new MemoryChunk(id, shm, helper_);
   chunks_.push_back(mc);
   void* mem = mc->Alloc(size);
   GPU_DCHECK(mem);
   *shm_id = mc->shm_id();
   *shm_offset = mc->GetOffset(mem);
@@ skipping 34 matching lines @@
     } else {
       ++iter;
     }
   }
 }
 
 }  // namespace gpu