Redirect handling in the resource_prefetch_predictor.

chrome/browser/predictors/resource_prefetch_predictor.h

Index: chrome/browser/predictors/resource_prefetch_predictor.h
diff --git a/chrome/browser/predictors/resource_prefetch_predictor.h b/chrome/browser/predictors/resource_prefetch_predictor.h
index c3177cdd124ce71d53eed9a3b69d503e9accb56e..6e566b2a042847dcbf98d3ecd3985cd0a24fef88 100644
--- a/chrome/browser/predictors/resource_prefetch_predictor.h
+++ b/chrome/browser/predictors/resource_prefetch_predictor.h
@@ -99,6 +99,15 @@ class ResourcePrefetchPredictor
                                   URLRequestSummary* summary);
   };
 
+  // Stores information about inflight navigations.
+  struct Navigation {
+    explicit Navigation(const GURL& initial_url);
+    ~Navigation();
+
+    GURL initial_url;

[Benoit L, 2016/09/26 12:51:14]

nit: Can you add a comment to specify whether this is before or after redirects?

[alexilin, 2016/09/26 15:38:28]

Done.

+    std::vector<URLRequestSummary> subresource_requests;
+  };
+
   ResourcePrefetchPredictor(const ResourcePrefetchPredictorConfig& config,
                             Profile* profile);
   ~ResourcePrefetchPredictor() override;
@@ -146,6 +155,8 @@ class ResourcePrefetchPredictor
   FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest, NavigationUrlNotInDB);
   FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest,
                            NavigationUrlNotInDBAndDBFull);
+  FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest, RedirectUrlNotInDB);
+  FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest, RedirectUrlInDB);
   FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest, OnMainFrameRequest);
   FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest, OnMainFrameRedirect);
   FRIEND_TEST_ALL_PREFIXES(ResourcePrefetchPredictorTest,
@@ -161,8 +172,9 @@ class ResourcePrefetchPredictor
 
   typedef ResourcePrefetchPredictorTables::PrefetchData PrefetchData;
   typedef ResourcePrefetchPredictorTables::PrefetchDataMap PrefetchDataMap;
-  typedef std::map<NavigationID, linked_ptr<std::vector<URLRequestSummary> > >
-      NavigationMap;
+  typedef ResourcePrefetchPredictorTables::RedirectDataMap RedirectDataMap;
+
+  typedef std::map<NavigationID, std::unique_ptr<Navigation>> NavigationMap;
 
   // Returns true if the main page request is supported for prediction.
   static bool IsHandledMainPage(net::URLRequest* request);
@@ -216,9 +228,11 @@ class ResourcePrefetchPredictor
   void StartInitialization();
 
   // Callback for task to read predictor database. Takes ownership of
-  // |url_data_map| and |host_data_map|.
+  // all arguments.
   void CreateCaches(std::unique_ptr<PrefetchDataMap> url_data_map,
-                    std::unique_ptr<PrefetchDataMap> host_data_map);
+                    std::unique_ptr<PrefetchDataMap> host_data_map,
+                    std::unique_ptr<RedirectDataMap> url_redirect_data_map,
+                    std::unique_ptr<RedirectDataMap> host_redirect_data_map);
 
   // Called during initialization when history is read and the predictor
   // database has been read.
@@ -239,20 +253,33 @@ class ResourcePrefetchPredictor
   // Callback for GetUrlVisitCountTask.
   void OnVisitCountLookup(size_t visit_count,
                           const NavigationID& navigation_id,
-                          const std::vector<URLRequestSummary>& requests);
+                          const Navigation& navigation);
 
   // Removes the oldest entry in the input |data_map|, also deleting it from the
   // predictor database.
   void RemoveOldestEntryInPrefetchDataMap(PrefetchKeyType key_type,
                                           PrefetchDataMap* data_map);
 
+  void RemoveOldestEntryInRedirectDataMap(PrefetchKeyType key_type,
+                                          RedirectDataMap* data_map);
+
   // Merges resources in |new_resources| into the |data_map| and correspondingly
-  // updates the predictor database.
+  // updates the predictor database. Also calls LearnRedirect if relevant.
   void LearnNavigation(const std::string& key,
                        PrefetchKeyType key_type,
                        const std::vector<URLRequestSummary>& new_resources,
                        size_t max_data_map_size,
-                       PrefetchDataMap* data_map);
+                       PrefetchDataMap* data_map,
+                       const std::string& redirect_origin_key,
+                       RedirectDataMap* redirect_map);
+
+  // Updates information about final redirect destination for |key| in
+  // |redirect_map| and correspondingly updates the predictor database
+  void LearnRedirect(const std::string& key,
+                     PrefetchKeyType key_type,
+                     const std::string& final_redirect,
+                     size_t max_redirect_map_size,
+                     RedirectDataMap* redirect_map);
 
   // Reports overall page load time.
   void ReportPageLoadTimeStats(base::TimeDelta plt) const;
@@ -289,12 +316,13 @@ class ResourcePrefetchPredictor
   scoped_refptr<ResourcePrefetcherManager> prefetch_manager_;
   base::CancelableTaskTracker history_lookup_consumer_;
 
-  // Map of all the navigations in flight to their resource requests.
-  NavigationMap inflight_navigations_;
-
   // Copy of the data in the predictor tables.
   std::unique_ptr<PrefetchDataMap> url_table_cache_;
   std::unique_ptr<PrefetchDataMap> host_table_cache_;
+  std::unique_ptr<RedirectDataMap> url_redirect_table_cache_;
+  std::unique_ptr<RedirectDataMap> host_redirect_table_cache_;
+
+  NavigationMap inflight_navigations_;
 
   ScopedObserver<history::HistoryService, history::HistoryServiceObserver>
       history_service_observer_;