[scheduler] Add WakeupBudgetPool.

third_party/WebKit/Source/platform/scheduler/renderer/budget_pool.h

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_RENDERER_BUDGET_POOL_H_
 #define THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_RENDERER_BUDGET_POOL_H_
 
 #include <unordered_set>
 
 #include "base/callback.h"
-#include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/optional.h"
 #include "base/time/time.h"
 #include "platform/scheduler/base/lazy_now.h"
 
 namespace base {
 namespace trace_event {
 class TracedValue;
 }
 }
 
 namespace blink {
 namespace scheduler {
 
 class TaskQueue;
 class BudgetPoolController;
+enum class QueueBlockType;
 
 // BudgetPool represents a group of task queues which share a limit
 // on a resource. This limit applies when task queues are already throttled
 // by TaskQueueThrottler.
 class PLATFORM_EXPORT BudgetPool {
  public:
   virtual ~BudgetPool();
 
   const char* Name() const;
 
   // Report task run time to the budget pool.
-  virtual void RecordTaskRunTime(base::TimeTicks start_time,
+  virtual void RecordTaskRunTime(TaskQueue* queue,
+                                 base::TimeTicks start_time,
                                  base::TimeTicks end_time) = 0;
 
-  // Retuns earliest time (can be in the past) when the next task can run.
-  virtual base::TimeTicks GetNextAllowedRunTime() = 0;
+  // Returns the earliest time when the next pump can be scheduled to run
+  // new tasks.
+  virtual base::TimeTicks GetNextAllowedRunTime(
+      base::TimeTicks desired_run_time) const = 0;
 
-  // Returns true at a task can be run immediately at the given time.
-  virtual bool HasEnoughBudgetToRun(base::TimeTicks now) = 0;
+  // Returns true if a task can run at the given time.
+  virtual bool CanRunTasksAt(base::TimeTicks moment, bool is_wake_up) const = 0;
+
+  // Notifies budget pool that queue has work with desired run time.
+  virtual void OnQueueNextWakeUpChanged(TaskQueue* queue,
+                                        base::TimeTicks now,
+                                        base::TimeTicks desired_run_time) = 0;
+
+  // Notifies budget pool that wakeup has happened.
+  virtual void OnWakeUp(base::TimeTicks now) = 0;
+
+  // Specify how this budget pool should block affected queues.
+  virtual QueueBlockType GetBlockType() const = 0;
 
   // Returns state for tracing.
   virtual void AsValueInto(base::trace_event::TracedValue* state,
                            base::TimeTicks now) const = 0;
 
   // Adds |queue| to given pool. If the pool restriction does not allow
   // a task to be run immediately and |queue| is throttled, |queue| becomes
   // disabled.
   void AddQueue(base::TimeTicks now, TaskQueue* queue);
 
   // Removes |queue| from given pool. If it is throttled, it does not
-  // become enabled immediately, but a call to |PumpThrottledTasks|
-  // is scheduled.
+  // become enabled immediately, but a wake-up is scheduled if needed.
   void RemoveQueue(base::TimeTicks now, TaskQueue* queue);
 
+  // Unlike RemoveQueue, does not schedule a new wake-up for the queue.
+  void UnregisterQueue(TaskQueue* queue);
+
   // Enables this time budget pool. Queues from this pool will be
   // throttled based on their run time.
   void EnableThrottling(LazyNow* now);
 
   // Disables with time budget pool. Queues from this pool will not be
   // throttled based on their run time. A call to |PumpThrottledTasks|
   // will be scheduled to enable this queues back again and respect
   // timer alignment. Internal budget level will not regenerate with time.
   void DisableThrottling(LazyNow* now);
 
   bool IsThrottlingEnabled() const;
 
   // All queues should be removed before calling Close().
   void Close();
 
   // Block all associated queues and schedule them to run when appropriate.
   void BlockThrottledQueues(base::TimeTicks now);
 
  protected:
   BudgetPool(const char* name, BudgetPoolController* budget_pool_controller);
 
   const char* name_;  // NOT OWNED
 
   BudgetPoolController* budget_pool_controller_;
 
   std::unordered_set<TaskQueue*> associated_task_queues_;
   bool is_enabled_;
-};
-
-// CPUTimeBudgetPool represents a collection of task queues which share a limit
-// on total cpu time.
-class PLATFORM_EXPORT CPUTimeBudgetPool : public BudgetPool {
- public:
-  CPUTimeBudgetPool(const char* name,
-                    BudgetPoolController* budget_pool_controller,
-                    base::TimeTicks now);
-
-  ~CPUTimeBudgetPool();
-
-  // Set max budget level, base::nullopt represent absence of max level.
-  // Max budget level prevents accumulating arbitrary large budgets when
-  // page is inactive for a very long time.
-  void SetMaxBudgetLevel(base::TimeTicks now,
-                         base::Optional<base::TimeDelta> max_budget_level);
-
-  // Set max throttling duration, base::nullopt represents absense of it.
-  // Max throttling duration prevents page from being throttled for
-  // a very long period after a single long task.
-  void SetMaxThrottlingDelay(
-      base::TimeTicks now,
-      base::Optional<base::TimeDelta> max_throttling_delay);
-
-  // Set minimal budget level required to run a task. If budget pool was
-  // exhausted, it needs to accumulate at least |min_budget_to_run| time units
-  // to unblock and run tasks again. When unblocked, it still can run tasks
-  // when budget is positive but less than this level until being blocked
-  // until being blocked when budget reaches zero.
-  // This is needed for integration with WakeUpBudgetPool to prevent a situation
-  // when wake-up happened but time budget pool allows only one task to run at
-  // the moment.
-  // It is recommended to use the same value for this and WakeUpBudgetPool's
-  // wake-up window length.
-  // NOTE: This does not have an immediate effect and does not call
-  // BudgetPoolController::UnblockQueue.
-  void SetMinBudgetLevelToRun(base::TimeTicks now,
-                              base::TimeDelta min_budget_level_to_run);
-
-  // Throttle task queues from this time budget pool if tasks are running
-  // for more than |cpu_percentage| per cent of wall time.
-  // This function does not affect internal time budget level.
-  void SetTimeBudgetRecoveryRate(base::TimeTicks now, double cpu_percentage);
-
-  // Increase budget level by given value. This function DOES NOT unblock
-  // queues even if they are allowed to run with increased budget level.
-  void GrantAdditionalBudget(base::TimeTicks now, base::TimeDelta budget_level);
-
-  // Set callback which will be called every time when this budget pool
-  // is throttled. Throttling duration (time until the queue is allowed
-  // to run again) is passed as a parameter to callback.
-  void SetReportingCallback(
-      base::Callback<void(base::TimeDelta)> reporting_callback);
-
-  // BudgetPool implementation:
-  void RecordTaskRunTime(base::TimeTicks start_time,
-                         base::TimeTicks end_time) final;
-  bool HasEnoughBudgetToRun(base::TimeTicks now) final;
-  base::TimeTicks GetNextAllowedRunTime() final;
-  void AsValueInto(base::trace_event::TracedValue* state,
-                   base::TimeTicks now) const final;
 
  private:
-  FRIEND_TEST_ALL_PREFIXES(TaskQueueThrottlerTest, CPUTimeBudgetPool);
-
-  // Advances |last_checkpoint_| to |now| if needed and recalculates
-  // budget level.
-  void Advance(base::TimeTicks now);
-
-  // Increase |current_budget_level_| to satisfy max throttling duration
-  // condition if necessary.
-  // Decrease |current_budget_level_| to satisfy max budget level
-  // condition if necessary.
-  void EnforceBudgetLevelRestrictions();
-
-  // Max budget level which we can accrue.
-  // Tasks will be allowed to run for this time before being throttled
-  // after a very long period of inactivity.
-  base::Optional<base::TimeDelta> max_budget_level_;
-  // Max throttling delay places a lower limit on time budget level,
-  // ensuring that one long task does not cause extremely long throttling.
-  // Note that this is not a guarantee that every task will run
-  // after desired run time + max throttling duration, but a guarantee
-  // that at least one task will be run every max_throttling_delay.
-  base::Optional<base::TimeDelta> max_throttling_delay_;
-  // See CPUTimeBudgetPool::SetMinBudgetLevelToRun.
-  base::TimeDelta min_budget_level_to_run_;
-
-  base::TimeDelta current_budget_level_;
-  base::TimeTicks last_checkpoint_;
-  double cpu_percentage_;
-
-  base::Callback<void(base::TimeDelta)> reporting_callback_;
-
-  DISALLOW_COPY_AND_ASSIGN(CPUTimeBudgetPool);
+  void DissociateQueue(TaskQueue* queue);
 };
 
 }  // namespace scheduler
 }  // namespace blink
 
 #endif  // THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_RENDERER_BUDGET_POOL_H_