[NOT FOR LANDING] Detailed loading traces

net/http/http_cache.cc

Index: net/http/http_cache.cc
diff --git a/net/http/http_cache.cc b/net/http/http_cache.cc
index f572c14f56968b846720d4b05ce2cfd1c107fe28..87f2d7964a3fb8ca2abaf47fe383f541043dede6 100644
--- a/net/http/http_cache.cc
+++ b/net/http/http_cache.cc
@@ -7,6 +7,7 @@
 #include <algorithm>
 #include <utility>
 
+#include "base/trace_event/trace_event.h"
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/callback.h"
@@ -390,6 +391,7 @@ disk_cache::Backend* HttpCache::GetCurrentBackend() const {
 bool HttpCache::ParseResponseInfo(const char* data, int len,
                                   HttpResponseInfo* response_info,
                                   bool* response_truncated) {
+  TRACE_EVENT0("toplevel", "HttpCache::ParseResponseInfo");
   base::Pickle pickle(data, len);
   return response_info->InitFromPickle(pickle, response_truncated);
 }
@@ -717,11 +719,13 @@ void HttpCache::DeletePendingOp(PendingOp* pending_op) {
 
 int HttpCache::OpenEntry(const std::string& key, ActiveEntry** entry,
                          Transaction* trans) {
+  TRACE_EVENT0("toplevel", "HttpCache::OpenEntry::A");
   ActiveEntry* active_entry = FindActiveEntry(key);
   if (active_entry) {
     *entry = active_entry;
     return OK;
   }
+  TRACE_EVENT0("toplevel", "HttpCache::OpenEntry::B");
 
   WorkItem* item = new WorkItem(WI_OPEN_ENTRY, trans, entry);
   PendingOp* pending_op = GetPendingOp(key);
@@ -729,15 +733,19 @@ int HttpCache::OpenEntry(const std::string& key, ActiveEntry** entry,
     pending_op->pending_queue.push_back(item);
     return ERR_IO_PENDING;
   }
+  TRACE_EVENT0("toplevel", "HttpCache::OpenEntry::C");
 
   DCHECK(pending_op->pending_queue.empty());
 
   pending_op->writer = item;
   pending_op->callback = base::Bind(&HttpCache::OnPendingOpComplete,
                                     GetWeakPtr(), pending_op);
+  TRACE_EVENT0("toplevel", "HttpCache::OpenEntry::D");
 
   int rv = disk_cache_->OpenEntry(key, &(pending_op->disk_entry),
                                   pending_op->callback);
+  TRACE_EVENT0("toplevel", "HttpCache::OpenEntry::E");
+
   if (rv != ERR_IO_PENDING) {
     item->ClearTransaction();
     pending_op->callback.Run(rv);
@@ -824,6 +832,7 @@ int HttpCache::AddTransactionToEntry(ActiveEntry* entry, Transaction* trans) {
 
 void HttpCache::DoneWithEntry(ActiveEntry* entry, Transaction* trans,
                               bool cancel) {
+  TRACE_EVENT0("toplevel", "HttpCache::DoneWithEntry");
   // If we already posted a task to move on to the next transaction and this was
   // the writer, there is nothing to cancel.
   if (entry->will_process_pending_queue && entry->readers.empty())
@@ -915,6 +924,8 @@ LoadState HttpCache::GetLoadStateForPendingTransaction(
 }
 
 void HttpCache::RemovePendingTransaction(Transaction* trans) {
+  TRACE_EVENT0("toplevel", "HttpCache::RemovePendingTransaction");
+
   ActiveEntriesMap::const_iterator i = active_entries_.find(trans->key());
   bool found = false;
   if (i != active_entries_.end())