Adding instrumentation to locate the source of jankiness.

content/browser/loader/resource_dispatcher_host_impl.cc

Index: content/browser/loader/resource_dispatcher_host_impl.cc
diff --git a/content/browser/loader/resource_dispatcher_host_impl.cc b/content/browser/loader/resource_dispatcher_host_impl.cc
index fa9c0442eab427857bb35e2af52400fbc225d749..da6ebafea626d0c3be4d25e820f4f816f7ad06c2 100644
--- a/content/browser/loader/resource_dispatcher_host_impl.cc
+++ b/content/browser/loader/resource_dispatcher_host_impl.cc
@@ -21,6 +21,7 @@
 #include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/sparse_histogram.h"
+#include "base/profiler/scoped_tracker.h"
 #include "base/stl_util.h"
 #include "base/third_party/dynamic_annotations/dynamic_annotations.h"
 #include "content/browser/appcache/appcache_interceptor.h"
@@ -2151,6 +2152,11 @@ void LoadInfoUpdateCallback(const LoadInfoMap& info_map) {
 }  // namespace
 
 void ResourceDispatcherHostImpl::UpdateLoadStates() {
+  // TODO(pkasting): Remove ScopedTracker below once crbug.com/455952 is
+  // fixed.
+  tracked_objects::ScopedTracker tracking_profile1(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION(
+          "455952 ResourceDispatcherHostImpl::UpdateLoadStates1"));
   // Populate this map with load state changes, and then send them on to the UI
   // thread where they can be passed along to the respective RVHs.
   LoadInfoMap info_map;
@@ -2160,48 +2166,62 @@ void ResourceDispatcherHostImpl::UpdateLoadStates() {
   // Determine the largest upload size of all requests
   // in each View (good chance it's zero).
   std::map<GlobalRoutingID, uint64> largest_upload_size;
-  for (i = pending_loaders_.begin(); i != pending_loaders_.end(); ++i) {
-    net::URLRequest* request = i->second->request();
-    ResourceRequestInfoImpl* info = i->second->GetRequestInfo();
-    uint64 upload_size = request->GetUploadProgress().size();
-    if (request->GetLoadState().state != net::LOAD_STATE_SENDING_REQUEST)
-      upload_size = 0;
-    GlobalRoutingID id(info->GetGlobalRoutingID());
-    if (upload_size && largest_upload_size[id] < upload_size)
-      largest_upload_size[id] = upload_size;
+  {
+    // TODO(pkasting): Remove ScopedTracker below once crbug.com/455952 is
+    // fixed.
+    tracked_objects::ScopedTracker tracking_profile2(
+        FROM_HERE_WITH_EXPLICIT_FUNCTION(

[vadimt, 2015/02/06 01:48:08]

Will work, but you don't need curlies. The time in the nested instrumentation
(UpdateLoadStates3) will be subtracted anyways.

[Peter Kasting, 2015/02/06 01:54:54]

I didn't want the code at the bottom of the function included in the time for
either of these last two objects.

It's moot anyway, I'm changing how I instrument this based on comments in bug
455952.

+            "455952 ResourceDispatcherHostImpl::UpdateLoadStates2"));
+    for (i = pending_loaders_.begin(); i != pending_loaders_.end(); ++i) {
+      net::URLRequest* request = i->second->request();
+      ResourceRequestInfoImpl* info = i->second->GetRequestInfo();
+      uint64 upload_size = request->GetUploadProgress().size();
+      if (request->GetLoadState().state != net::LOAD_STATE_SENDING_REQUEST)
+        upload_size = 0;
+      GlobalRoutingID id(info->GetGlobalRoutingID());
+      if (upload_size && largest_upload_size[id] < upload_size)
+        largest_upload_size[id] = upload_size;
+    }
   }
 
-  for (i = pending_loaders_.begin(); i != pending_loaders_.end(); ++i) {
-    net::URLRequest* request = i->second->request();
-    ResourceRequestInfoImpl* info = i->second->GetRequestInfo();
-    net::LoadStateWithParam load_state = request->GetLoadState();
-    net::UploadProgress progress = request->GetUploadProgress();
-
-    // We also poll for upload progress on this timer and send upload
-    // progress ipc messages to the plugin process.
-    i->second->ReportUploadProgress();
-
-    GlobalRoutingID id(info->GetGlobalRoutingID());
-
-    // If a request is uploading data, ignore all other requests so that the
-    // upload progress takes priority for being shown in the status bar.
-    if (largest_upload_size.find(id) != largest_upload_size.end() &&
-        progress.size() < largest_upload_size[id])
-      continue;
-
-    net::LoadStateWithParam to_insert = load_state;
-    LoadInfoMap::iterator existing = info_map.find(id);
-    if (existing != info_map.end()) {
-      to_insert =
-          MoreInterestingLoadState(existing->second.load_state, load_state);
-      if (to_insert.state == existing->second.load_state.state)
+  {
+    // TODO(pkasting): Remove ScopedTracker below once crbug.com/455952 is
+    // fixed.
+    tracked_objects::ScopedTracker tracking_profile3(
+        FROM_HERE_WITH_EXPLICIT_FUNCTION(
+            "455952 ResourceDispatcherHostImpl::UpdateLoadStates3"));
+    for (i = pending_loaders_.begin(); i != pending_loaders_.end(); ++i) {
+      net::URLRequest* request = i->second->request();
+      ResourceRequestInfoImpl* info = i->second->GetRequestInfo();
+      net::LoadStateWithParam load_state = request->GetLoadState();
+      net::UploadProgress progress = request->GetUploadProgress();
+
+      // We also poll for upload progress on this timer and send upload
+      // progress ipc messages to the plugin process.
+      i->second->ReportUploadProgress();
+
+      GlobalRoutingID id(info->GetGlobalRoutingID());
+
+      // If a request is uploading data, ignore all other requests so that the
+      // upload progress takes priority for being shown in the status bar.
+      if (largest_upload_size.find(id) != largest_upload_size.end() &&
+          progress.size() < largest_upload_size[id])
         continue;
+
+      net::LoadStateWithParam to_insert = load_state;
+      LoadInfoMap::iterator existing = info_map.find(id);
+      if (existing != info_map.end()) {
+        to_insert =
+            MoreInterestingLoadState(existing->second.load_state, load_state);
+        if (to_insert.state == existing->second.load_state.state)
+          continue;
+      }
+      LoadInfo& load_info = info_map[id];
+      load_info.url = request->url();
+      load_info.load_state = to_insert;
+      load_info.upload_size = progress.size();
+      load_info.upload_position = progress.position();
     }
-    LoadInfo& load_info = info_map[id];
-    load_info.url = request->url();
-    load_info.load_state = to_insert;
-    load_info.upload_size = progress.size();
-    load_info.upload_position = progress.position();
   }
 
   if (info_map.empty())