[scheduler] Add WakeupBudgetPool.

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

 // 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.
 
 #include "platform/scheduler/renderer/budget_pool.h"
 
 #include <cstdint>
 
 #include "base/format_macros.h"
 #include "base/logging.h"
@@ skipping 30 matching lines @@
 BudgetPool::~BudgetPool() {}
 
 const char* BudgetPool::Name() const {
   return name_;
 }
 
 void BudgetPool::AddQueue(base::TimeTicks now, TaskQueue* queue) {
   budget_pool_controller_->AddQueueToBudgetPool(queue, this);
   associated_task_queues_.insert(queue);
 
-  if (!is_enabled_ || !budget_pool_controller_->IsThrottled(queue))
+  if (!is_enabled_)
     return;
+  budget_pool_controller_->UpdateQueueThrottlingState(now, queue);
+}
 
-  budget_pool_controller_->BlockQueue(now, queue);
+void BudgetPool::UnregisterQueue(TaskQueue* queue) {
+  DissociateQueue(queue);
 }
 
 void BudgetPool::RemoveQueue(base::TimeTicks now, TaskQueue* queue) {
+  DissociateQueue(queue);
+
+  if (!is_enabled_)
+    return;
+
+  budget_pool_controller_->UpdateQueueThrottlingState(now, queue);
+}
+
+void BudgetPool::DissociateQueue(TaskQueue* queue) {
   budget_pool_controller_->RemoveQueueFromBudgetPool(queue, this);
   associated_task_queues_.erase(queue);
-
-  if (!is_enabled_ || !budget_pool_controller_->IsThrottled(queue))
-    return;
-
-  budget_pool_controller_->UnblockQueue(now, queue);
 }
 
 void BudgetPool::EnableThrottling(LazyNow* lazy_now) {
   if (is_enabled_)
     return;
   is_enabled_ = true;
 
   TRACE_EVENT0("renderer.scheduler", "BudgetPool_EnableThrottling");
 
   BlockThrottledQueues(lazy_now->Now());
 }
 
 void BudgetPool::DisableThrottling(LazyNow* lazy_now) {
   if (!is_enabled_)
     return;
   is_enabled_ = false;
 
   TRACE_EVENT0("renderer.scheduler", "BudgetPool_DisableThrottling");
 
   for (TaskQueue* queue : associated_task_queues_) {
-    if (!budget_pool_controller_->IsThrottled(queue))
-      continue;
-
-    budget_pool_controller_->UnblockQueue(lazy_now->Now(), queue);
+    budget_pool_controller_->UpdateQueueThrottlingState(lazy_now->Now(), queue);
   }
 
   // TODO(altimin): We need to disable TimeBudgetQueues here or they will
   // regenerate extra time budget when they are disabled.
 }
 
 bool BudgetPool::IsThrottlingEnabled() const {
   return is_enabled_;
 }
 
 void BudgetPool::Close() {
   DCHECK_EQ(0u, associated_task_queues_.size());
 
   budget_pool_controller_->UnregisterBudgetPool(this);
 }
 
 void BudgetPool::BlockThrottledQueues(base::TimeTicks now) {
   for (TaskQueue* queue : associated_task_queues_)
-    budget_pool_controller_->BlockQueue(now, queue);
+    budget_pool_controller_->UpdateQueueThrottlingState(now, queue);
 }
 
 CPUTimeBudgetPool::CPUTimeBudgetPool(
     const char* name,
     BudgetPoolController* budget_pool_controller,
     base::TimeTicks now)
     : BudgetPool(name, budget_pool_controller),
       last_checkpoint_(now),
       cpu_percentage_(1) {}
 
 CPUTimeBudgetPool::~CPUTimeBudgetPool() {}
 
+QueueBlockType CPUTimeBudgetPool::GetBlockType() const {
+  return QueueBlockType::kAllTasks;
+}
+
 void CPUTimeBudgetPool::SetMaxBudgetLevel(
     base::TimeTicks now,
     base::Optional<base::TimeDelta> max_budget_level) {
   Advance(now);
   max_budget_level_ = max_budget_level;
   EnforceBudgetLevelRestrictions();
 }
 
 void CPUTimeBudgetPool::SetMaxThrottlingDelay(
     base::TimeTicks now,
@@ skipping 22 matching lines @@
   Advance(now);
   current_budget_level_ += budget_level;
   EnforceBudgetLevelRestrictions();
 }
 
 void CPUTimeBudgetPool::SetReportingCallback(
     base::Callback<void(base::TimeDelta)> reporting_callback) {
   reporting_callback_ = reporting_callback;
 }
 
-bool CPUTimeBudgetPool::HasEnoughBudgetToRun(base::TimeTicks now) {
-  return now >= GetNextAllowedRunTime();
+bool CPUTimeBudgetPool::CanRunTasksAt(base::TimeTicks now,
+                                      bool is_wake_up) const {
+  return now >= GetNextAllowedRunTime(now);
 }
 
-base::TimeTicks CPUTimeBudgetPool::GetNextAllowedRunTime() {
+bool CPUTimeBudgetPool::CanRunTasksUntil(base::TimeTicks now,
+                                         base::TimeTicks moment) const {
+  return CanRunTasksAt(now, false);
+}
+
+base::TimeTicks CPUTimeBudgetPool::GetNextAllowedRunTime(
+    base::TimeTicks desired_run_time) const {
   if (!is_enabled_ || current_budget_level_.InMicroseconds() >= 0) {
     return last_checkpoint_;
   } else {
     // Subtract because current_budget is negative.
     return last_checkpoint_ +
            (-current_budget_level_ + min_budget_level_to_run_) /
                cpu_percentage_;
   }
 }
 
-void CPUTimeBudgetPool::RecordTaskRunTime(base::TimeTicks start_time,
+void CPUTimeBudgetPool::RecordTaskRunTime(TaskQueue* queue,
+                                          base::TimeTicks start_time,
                                           base::TimeTicks end_time) {
   DCHECK_LE(start_time, end_time);
   Advance(end_time);
   if (is_enabled_) {
     base::TimeDelta old_budget_level = current_budget_level_;
     current_budget_level_ -= (end_time - start_time);
     EnforceBudgetLevelRestrictions();
 
     if (!reporting_callback_.is_null() && old_budget_level.InSecondsF() > 0 &&
         current_budget_level_.InSecondsF() < 0) {
       reporting_callback_.Run(-current_budget_level_ / cpu_percentage_);
     }
   }
+
+  if (current_budget_level_.InSecondsF() < 0) {
+    BlockThrottledQueues(end_time);
+  }
 }
 
+void CPUTimeBudgetPool::OnTaskQueueHasWork(TaskQueue* queue,
+                                           base::TimeTicks now,
+                                           base::TimeTicks desired_run_time) {
+  budget_pool_controller_->UpdateQueueThrottlingState(now, queue);
+}
+
+void CPUTimeBudgetPool::OnWakeUp(base::TimeTicks now) {}
+
 void CPUTimeBudgetPool::AsValueInto(base::trace_event::TracedValue* state,
                                     base::TimeTicks now) const {
   state->BeginDictionary(name_);
 
   state->SetString("name", name_);
   state->SetDouble("time_budget", cpu_percentage_);
   state->SetDouble("time_budget_level_in_seconds",
                    current_budget_level_.InSecondsF());
   state->SetDouble("last_checkpoint_seconds_ago",
                    (now - last_checkpoint_).InSecondsF());
@@ skipping 35 matching lines @@
         std::min(current_budget_level_, max_budget_level_.value());
   }
   if (max_throttling_delay_) {
     // Current budget level may be negative.
     current_budget_level_ =
         std::max(current_budget_level_,
                  -max_throttling_delay_.value() * cpu_percentage_);
   }
 }
 
+WakeUpBudgetPool::WakeUpBudgetPool(const char* name,
+                                   BudgetPoolController* budget_pool_controller,
+                                   base::TimeTicks now)
+    : BudgetPool(name, budget_pool_controller), wakeups_per_second_(1) {}
+
+WakeUpBudgetPool::~WakeUpBudgetPool() {}
+
+QueueBlockType WakeUpBudgetPool::GetBlockType() const {
+  return QueueBlockType::kNewTasksOnly;
+}
+
+void WakeUpBudgetPool::SetWakeUpRate(double wakeups_per_second) {
+  wakeups_per_second_ = wakeups_per_second;
+}
+
+void WakeUpBudgetPool::SetWakeUpDuration(base::TimeDelta duration) {
+  wakeup_duration_ = duration;
+}
+
+void WakeUpBudgetPool::RecordTaskRunTime(TaskQueue* queue,
+                                         base::TimeTicks start_time,
+                                         base::TimeTicks end_time) {
+  budget_pool_controller_->UpdateQueueThrottlingState(end_time, queue);
+}
+
+base::Optional<base::TimeTicks> WakeUpBudgetPool::NextWakeUp() const {
+  if (!last_wakeup_)
+    return base::nullopt;
+  // Subtract 1 microsecond to work with time alignment in task queue throttler.
+  // This is needed due to alignment mechanism in task queue throttler --
+  // whole seconds need to be aligned to the next second to deal with immediate
+  // tasks correctly. By subtracting 1 microsecond we ensure that next wakeup
+  // gets aligned to a correct time.
+  return last_wakeup_.value() +
+         base::TimeDelta::FromSeconds(1 / wakeups_per_second_) -
+         base::TimeDelta::FromMicroseconds(1);

[Sami, 2017/04/26 13:09:08]

Would it be less arbitrary to subtract base::TimeDelta::FromInternalValue(1)?

[altimin, 2017/04/26 14:31:29]

The current approach is easier to test.

+}
+
+bool WakeUpBudgetPool::CanRunTasksAt(base::TimeTicks now,
+                                     bool is_wake_up) const {
+  if (!last_wakeup_)

[Sami, 2017/04/26 13:09:08]

If we haven't had a wake up, should we allow everything to run? (same question
below)

[altimin, 2017/04/26 14:31:29]

No, if we're throttled we should wait for a wake-up. In the beginning, when a
task queue is throttled, wake-up is a scheduled and a queue should wait for the
wake-up.

[Sami, 2017/04/27 12:12:30]

Okay, could you add a comment about that here please?

+    return false;
+  if (last_wakeup_ == now && is_wake_up)
+    return true;
+  return now < last_wakeup_.value() + wakeup_duration_;
+}
+
+bool WakeUpBudgetPool::CanRunTasksUntil(base::TimeTicks now,
+                                        base::TimeTicks moment) const {
+  if (!last_wakeup_)
+    return false;
+  DCHECK_LE(now, moment);
+  return now < last_wakeup_.value() + wakeup_duration_ &&
+         moment < last_wakeup_.value() + wakeup_duration_;
+}
+
+base::TimeTicks WakeUpBudgetPool::GetNextAllowedRunTime(
+    base::TimeTicks desired_run_time) const {
+  if (!last_wakeup_)
+    return desired_run_time;
+  if (desired_run_time < last_wakeup_.value() + wakeup_duration_)
+    return desired_run_time;
+  return std::max(desired_run_time, NextWakeUp().value());
+}
+
+void WakeUpBudgetPool::OnTaskQueueHasWork(TaskQueue* queue,
+                                          base::TimeTicks now,
+                                          base::TimeTicks desired_run_time) {
+  budget_pool_controller_->UpdateQueueThrottlingState(now, queue);
+}
+
+void WakeUpBudgetPool::OnWakeUp(base::TimeTicks now) {
+  last_wakeup_ = now;
+}
+
+void WakeUpBudgetPool::AsValueInto(base::trace_event::TracedValue* state,
+                                   base::TimeTicks now) const {
+  state->BeginDictionary(name_);
+
+  state->SetString("name", name_);
+  state->SetDouble("wakeups_per_second_rate", wakeups_per_second_);
+  state->SetDouble("wakeup_duration_in_seconds", wakeup_duration_.InSecondsF());
+  if (last_wakeup_) {
+    state->SetDouble("last_wakeup_seconds_ago",
+                     (now - last_wakeup_.value()).InSecondsF());
+  }
+  state->SetBoolean("is_enabled", is_enabled_);
+
+  state->BeginArray("task_queues");
+  for (TaskQueue* queue : associated_task_queues_) {
+    state->AppendString(PointerToId(queue));
+  }
+  state->EndArray();
+
+  state->EndDictionary();
+}
+
 }  // namespace scheduler
 }  // namespace blink