chrome/browser/memory/oom_priority_manager_delegate_chromeos.h

   1 // Copyright 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_MEMORY_OOM_PRIORITY_MANAGER_DELEGATE_CHROMEOS_H_
   6 #define CHROME_BROWSER_MEMORY_OOM_PRIORITY_MANAGER_DELEGATE_CHROMEOS_H_
   7
   8 #include <utility>
   9 #include <vector>
  10
  11 #include "base/containers/hash_tables.h"
  12 #include "base/process/process.h"
  13 #include "base/timer/timer.h"
  14 #include "chrome/browser/memory/oom_priority_manager.h"
  15 #include "chrome/browser/memory/tab_stats.h"
  16 #include "content/public/browser/notification_observer.h"
  17 #include "content/public/browser/notification_registrar.h"
  18
  19 namespace memory {
  20
  21 // The Chrome OS OomPriorityManagerDelegate is responsible for keeping the
  22 // renderers' scores up to date in /proc/<pid>/oom_score_adj.
  23 //
  24 // Note that AdjustOomPriorities will be called on the UI thread by
  25 // OomPriorityManager, but the actual work will take place on the file thread
  26 // (see implementation of AdjustOomPriorities).
  27 class OomPriorityManagerDelegate : public content::NotificationObserver {
  28  public:
  29   OomPriorityManagerDelegate();
  30   ~OomPriorityManagerDelegate() override;
  31
  32   // Return the score of a process.
  33   int GetOomScore(int child_process_host_id);
  34
  35   // Called when the timer fires, sets oom_adjust_score for all renderers.
  36   void AdjustOomPriorities(const TabStatsList& stats_list);
  37
  38  private:
  39   FRIEND_TEST_ALL_PREFIXES(OomPriorityManagerDelegateTest, GetProcessHandles);
  40
  41   // content::NotificationObserver:
  42   void Observe(int type,
  43                const content::NotificationSource& source,
  44                const content::NotificationDetails& details) override;
  45
  46   // Pair to hold child process host id and ProcessHandle.
  47   typedef std::pair<int, base::ProcessHandle> ProcessInfo;
  48
  49   // Returns a list of child process host ids and ProcessHandles from
  50   // |stats_list| with unique pids. If multiple tabs use the same process,
  51   // returns the first child process host id and corresponding pid. This implies
  52   // that the processes are selected based on their "most important" tab.
  53   static std::vector<ProcessInfo> GetChildProcessInfos(
  54       const TabStatsList& stats_list);
  55
  56   // Called by AdjustOomPriorities.
  57   void AdjustOomPrioritiesOnFileThread(TabStatsList stats_list);
  58
  59   // Posts AdjustFocusedTabScore task to the file thread.
  60   void OnFocusTabScoreAdjustmentTimeout();
  61
  62   // Sets the score of the focused tab to the least value.
  63   void AdjustFocusedTabScoreOnFileThread();
  64
  65   // Registrar to receive renderer notifications.
  66   content::NotificationRegistrar registrar_;
  67   // Timer to guarantee that the tab is focused for a certain amount of time.
  68   base::OneShotTimer<OomPriorityManagerDelegate> focus_tab_score_adjust_timer_;
  69   // This lock is for |oom_score_map_| and |focused_tab_process_info_|.
  70   base::Lock oom_score_lock_;
  71   // Map maintaining the child process host id - oom_score mapping.
  72   typedef base::hash_map<int, int> ProcessScoreMap;
  73   ProcessScoreMap oom_score_map_;
  74   // Holds the focused tab's child process host id.
  75   ProcessInfo focused_tab_process_info_;
  76
  77   DISALLOW_COPY_AND_ASSIGN(OomPriorityManagerDelegate);
  78 };
  79
  80 }  // namespace memory
  81
  82 #endif  // CHROME_BROWSER_MEMORY_OOM_PRIORITY_MANAGER_DELEGATE_CHROMEOS_H_