Optimized webstorage performance

content/browser/dom_storage/dom_storage_message_filter.cc

Index: content/browser/dom_storage/dom_storage_message_filter.cc
diff --git a/content/browser/dom_storage/dom_storage_message_filter.cc b/content/browser/dom_storage/dom_storage_message_filter.cc
index 15d19b308ec41271a4bd5d5279917adc26d94818..5828984e605f5da3307c89856850454f73da2bdc 100644
--- a/content/browser/dom_storage/dom_storage_message_filter.cc
+++ b/content/browser/dom_storage/dom_storage_message_filter.cc
@@ -7,6 +7,7 @@
 #include "base/auto_reset.h"
 #include "base/bind.h"
 #include "base/nullable_string16.h"
+#include "base/process_util.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "base/utf_string_conversions.h"
 #include "content/public/browser/user_metrics.h"
@@ -16,6 +17,8 @@
 #include "webkit/dom_storage/dom_storage_area.h"
 #include "webkit/dom_storage/dom_storage_host.h"
 #include "webkit/dom_storage/dom_storage_task_runner.h"
+#include "webkit/dom_storage/dom_storage_types.h"
+
 
 using content::BrowserThread;
 using content::UserMetricsAction;
@@ -91,6 +94,7 @@ bool DOMStorageMessageFilter::OnMessageReceived(const IPC::Message& message,
     IPC_MESSAGE_HANDLER(DOMStorageHostMsg_Key, OnKey)
     IPC_MESSAGE_HANDLER(DOMStorageHostMsg_GetItem, OnGetItem)
     IPC_MESSAGE_HANDLER(DOMStorageHostMsg_SetItem, OnSetItem)
+    IPC_MESSAGE_HANDLER(DOMStorageHostMsg_SetItemOpt, OnSetItemOpt)
     IPC_MESSAGE_HANDLER(DOMStorageHostMsg_SetItemAsync, OnSetItemAsync)
     IPC_MESSAGE_HANDLER(DOMStorageHostMsg_RemoveItem, OnRemoveItem)
     IPC_MESSAGE_HANDLER(DOMStorageHostMsg_RemoveItemAsync, OnRemoveItemAsync)
@@ -139,9 +143,39 @@ void DOMStorageMessageFilter::OnKey(int connection_id, unsigned index,
 
 void DOMStorageMessageFilter::OnGetItem(int connection_id,
                                         const string16& key,
+                                        int* ipc_flag,
+                                        base::SharedMemoryHandle* shm_handle,
+                                        unsigned* shm_size,
                                         NullableString16* value) {
   DCHECK(!BrowserThread::CurrentlyOn(BrowserThread::IO));
   *value = host_->GetAreaItem(connection_id, key);
+  int value_len = value->string().length()*sizeof(WebKit::WebUChar);
+  // small size data, go through channel
+  if (value->is_null() || value_len * sizeof(char16)
+      < dom_storage::kShmEnableThreshold) {
+    *ipc_flag = dom_storage::Channel;
+    *shm_size = 0;
+    return;
+  }
+
+  base::SharedMemory shared_buf;
+  // try shm for big size data,
+  // if fail, go through channel
+  if (!shared_buf.CreateAndMapAnonymous(value_len)) {
+    *ipc_flag = dom_storage::Channel;
+    *shm_size = 0;
+    return;
+  }
+  // go through shm
+  shared_buf.Lock();
+  memcpy(shared_buf.memory(), value->string().data(), value_len);
+  shared_buf.Unlock();
+  shared_buf.GiveToProcess(peer_handle(), shm_handle);
+  shared_buf.Close();
+  *ipc_flag = dom_storage::SharedMemory;
+  *shm_size = value->string().length();
+  string16 tmp;
+  *value = NullableString16(tmp, true);
 }
 
 void DOMStorageMessageFilter::OnSetItem(
@@ -156,6 +190,36 @@ void DOMStorageMessageFilter::OnSetItem(
     *result = WebKit::WebStorageArea::ResultBlockedByQuota;
 }
 
+void DOMStorageMessageFilter::OnSetItemOpt(
+    int connection_id, const string16& key,
+    const int value_len,
+    base::SharedMemoryHandle renderer_handle,
+    const GURL& page_url,
+    WebKit::WebStorageArea::Result* result,
+    NullableString16* old_value) {
+  DCHECK(!BrowserThread::CurrentlyOn(BrowserThread::IO));
+  string16 value;
+  *old_value = NullableString16(true);
+  // get value from shared memory
+  if (!base::SharedMemory::IsHandleValid(renderer_handle)) {
+      NOTREACHED() << "We got an invalid shared buffer handle!\n";
+      return;
+  }
+
+  base::SharedMemory shared_buf(renderer_handle, true, peer_handle());
+  shared_buf.Map(value_len*sizeof(char16));
+
+  shared_buf.Lock();
+  value.append(static_cast<char16*>(shared_buf.memory()), value_len);
+  shared_buf.Unlock();
+  shared_buf.Close();
+  //
+  if (host_->SetAreaItem(connection_id, key, value, page_url, old_value))
+    *result = WebKit::WebStorageArea::ResultOK;
+  else
+    *result = WebKit::WebStorageArea::ResultBlockedByQuota;
+}
+
 void DOMStorageMessageFilter::OnSetItemAsync(
     int connection_id, int operation_id, const string16& key,
     const string16& value, const GURL& page_url) {