Migrate ChromeOS to base::MemoryPressureMonitor

base/chromeos/memory_pressure_monitor_chromeos.cc

 // Copyright 2014 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 "base/chromeos/memory_pressure_observer_chromeos.h"
+#include "base/chromeos/memory_pressure_monitor_chromeos.h"
 
 #include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/process/process_metrics.h"
 #include "base/time/time.h"
 
 namespace base {
 
 namespace {
 
@@ skipping 20 matching lines @@
 enum MemoryPressureLevelUMA {
   MEMORY_PRESSURE_LEVEL_NONE = 0,
   MEMORY_PRESSURE_LEVEL_MODERATE,
   MEMORY_PRESSURE_LEVEL_CRITICAL,
   NUM_MEMORY_PRESSURE_LEVELS
 };
 
 // Converts a |MemoryPressureThreshold| value into a used memory percentage for
 // the moderate pressure event.
 int GetModerateMemoryThresholdInPercent(
-    MemoryPressureObserverChromeOS::MemoryPressureThresholds thresholds) {
-  return thresholds == MemoryPressureObserverChromeOS::
+    MemoryPressureMonitorChromeOS::MemoryPressureThresholds thresholds) {
+  return thresholds == MemoryPressureMonitorChromeOS::
                            THRESHOLD_AGGRESSIVE_CACHE_DISCARD ||
-         thresholds == MemoryPressureObserverChromeOS::THRESHOLD_AGGRESSIVE
+         thresholds == MemoryPressureMonitorChromeOS::THRESHOLD_AGGRESSIVE
              ? kAggressiveMemoryPressureModerateThresholdPercent
              : kNormalMemoryPressureModerateThresholdPercent;
 }
 
 // Converts a |MemoryPressureThreshold| value into a used memory percentage for
 // the critical pressure event.
 int GetCriticalMemoryThresholdInPercent(
-    MemoryPressureObserverChromeOS::MemoryPressureThresholds thresholds) {
-  return thresholds == MemoryPressureObserverChromeOS::
+    MemoryPressureMonitorChromeOS::MemoryPressureThresholds thresholds) {
+  return thresholds == MemoryPressureMonitorChromeOS::
                            THRESHOLD_AGGRESSIVE_TAB_DISCARD ||
-         thresholds == MemoryPressureObserverChromeOS::THRESHOLD_AGGRESSIVE
+         thresholds == MemoryPressureMonitorChromeOS::THRESHOLD_AGGRESSIVE
              ? kAggressiveMemoryPressureCriticalThresholdPercent
              : kNormalMemoryPressureCriticalThresholdPercent;
 }
 
 // Converts free percent of memory into a memory pressure value.
 MemoryPressureListener::MemoryPressureLevel GetMemoryPressureLevelFromFillLevel(
     int actual_fill_level,
     int moderate_threshold,
     int critical_threshold) {
   if (actual_fill_level < moderate_threshold)
     return MemoryPressureListener::MEMORY_PRESSURE_LEVEL_NONE;
   return actual_fill_level < critical_threshold
              ? MemoryPressureListener::MEMORY_PRESSURE_LEVEL_MODERATE
              : MemoryPressureListener::MEMORY_PRESSURE_LEVEL_CRITICAL;
 }
 
 }  // namespace
 
-MemoryPressureObserverChromeOS::MemoryPressureObserverChromeOS(
+MemoryPressureMonitorChromeOS::MemoryPressureMonitorChromeOS(
     MemoryPressureThresholds thresholds)
     : current_memory_pressure_level_(
           MemoryPressureListener::MEMORY_PRESSURE_LEVEL_NONE),
       moderate_pressure_repeat_count_(0),
       moderate_pressure_threshold_percent_(
           GetModerateMemoryThresholdInPercent(thresholds)),
       critical_pressure_threshold_percent_(
           GetCriticalMemoryThresholdInPercent(thresholds)),
       weak_ptr_factory_(this) {
   StartObserving();
 }
 
-MemoryPressureObserverChromeOS::~MemoryPressureObserverChromeOS() {
+MemoryPressureMonitorChromeOS::~MemoryPressureMonitorChromeOS() {
   StopObserving();
 }
 
-void MemoryPressureObserverChromeOS::ScheduleEarlyCheck() {
+void MemoryPressureMonitorChromeOS::ScheduleEarlyCheck() {
   MessageLoop::current()->PostTask(
       FROM_HERE,
-      Bind(&MemoryPressureObserverChromeOS::CheckMemoryPressure,
+      Bind(&MemoryPressureMonitorChromeOS::CheckMemoryPressure,
            weak_ptr_factory_.GetWeakPtr()));
 }
 
-void MemoryPressureObserverChromeOS::StartObserving() {
+MemoryPressureListener::MemoryPressureLevel
+MemoryPressureMonitorChromeOS::GetCurrentPressureLevel() const {
+  return current_memory_pressure_level_;
+}
+
+void MemoryPressureMonitorChromeOS::StartObserving() {
   timer_.Start(FROM_HERE,
                TimeDelta::FromMilliseconds(kMemoryPressureIntervalMs),
-               Bind(&MemoryPressureObserverChromeOS::
+               Bind(&MemoryPressureMonitorChromeOS::
                         CheckMemoryPressureAndRecordStatistics,
                     weak_ptr_factory_.GetWeakPtr()));
 }
 
-void MemoryPressureObserverChromeOS::StopObserving() {
+void MemoryPressureMonitorChromeOS::StopObserving() {
   // If StartObserving failed, StopObserving will still get called.
   timer_.Stop();
 }
 
-void MemoryPressureObserverChromeOS::CheckMemoryPressureAndRecordStatistics() {
+void MemoryPressureMonitorChromeOS::CheckMemoryPressureAndRecordStatistics() {
   CheckMemoryPressure();
 
   // Record UMA histogram statistics for the current memory pressure level.
   MemoryPressureLevelUMA memory_pressure_level_uma(MEMORY_PRESSURE_LEVEL_NONE);
   switch (current_memory_pressure_level_) {
     case MemoryPressureListener::MEMORY_PRESSURE_LEVEL_NONE:
       memory_pressure_level_uma = MEMORY_PRESSURE_LEVEL_NONE;
       break;
     case MemoryPressureListener::MEMORY_PRESSURE_LEVEL_MODERATE:
       memory_pressure_level_uma = MEMORY_PRESSURE_LEVEL_MODERATE;
       break;
     case MemoryPressureListener::MEMORY_PRESSURE_LEVEL_CRITICAL:
       memory_pressure_level_uma = MEMORY_PRESSURE_LEVEL_CRITICAL;
       break;
   }
 
   UMA_HISTOGRAM_ENUMERATION("ChromeOS.MemoryPressureLevel",
                             memory_pressure_level_uma,
                             NUM_MEMORY_PRESSURE_LEVELS);
 }
 
-void MemoryPressureObserverChromeOS::CheckMemoryPressure() {
+void MemoryPressureMonitorChromeOS::CheckMemoryPressure() {
   MemoryPressureListener::MemoryPressureLevel old_pressure =
       current_memory_pressure_level_;
   current_memory_pressure_level_ =
       GetMemoryPressureLevelFromFillLevel(GetUsedMemoryInPercent(),
                                           moderate_pressure_threshold_percent_,
                                           critical_pressure_threshold_percent_);
   // In case there is no memory pressure we do not notify.
   if (current_memory_pressure_level_ ==
       MemoryPressureListener::MEMORY_PRESSURE_LEVEL_NONE) {
     return;
@@ skipping 15 matching lines @@
     // When we reducing the pressure level from critical to moderate, we
     // restart the timeout and do not send another notification.
     moderate_pressure_repeat_count_ = 0;
     return;
   }
   moderate_pressure_repeat_count_ = 0;
   MemoryPressureListener::NotifyMemoryPressure(current_memory_pressure_level_);
 }
 
 // Gets the used ChromeOS memory in percent.
-int MemoryPressureObserverChromeOS::GetUsedMemoryInPercent() {
+int MemoryPressureMonitorChromeOS::GetUsedMemoryInPercent() {
   base::SystemMemoryInfoKB info;
   if (!base::GetSystemMemoryInfo(&info)) {
     VLOG(1) << "Cannot determine the free memory of the system.";
     return 0;
   }
   // TODO(skuhne): Instead of adding the kernel memory pressure calculation
   // logic here, we should have a kernel mechanism similar to the low memory
   // notifier in ChromeOS which offers multiple pressure states.
   // To track this, we have crbug.com/381196.
 
@@ skipping 17 matching lines @@
   // Available memory is the sum of free, swap and easy reclaimable memory.
   int available_memory =
       info.free + info.swap_free / kSwapWeight + file_memory;
 
   DCHECK(available_memory < total_memory);
   int percentage = ((total_memory - available_memory) * 100) / total_memory;
   return percentage;
 }
 
 }  // namespace base