hal/android/AndroidProcessPriority.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
   6
   7 #include "Hal.h"
   8
   9 #include "mozilla/java/GeckoProcessManagerWrappers.h"
  10 #include "mozilla/java/GeckoProcessTypeWrappers.h"
  11 #include "mozilla/java/ServiceAllocatorWrappers.h"
  12
  13 using namespace mozilla::hal;
  14
  15 /**
  16  * Bucket the Gecko HAL process priority level into one of the three Android
  17  * priority levels.
  18  */
  19 static mozilla::java::ServiceAllocator::PriorityLevel::LocalRef
  20 ToJavaPriorityLevel(const ProcessPriority aPriority) {
  21   if (aPriority >= PROCESS_PRIORITY_FOREGROUND) {
  22     return mozilla::java::ServiceAllocator::PriorityLevel::FOREGROUND();
  23   } else if (aPriority <= PROCESS_PRIORITY_PREALLOC &&
  24              aPriority >= PROCESS_PRIORITY_BACKGROUND_PERCEIVABLE) {
  25     return mozilla::java::ServiceAllocator::PriorityLevel::BACKGROUND();
  26   }
  27
  28   return mozilla::java::ServiceAllocator::PriorityLevel::IDLE();
  29 }
  30
  31 namespace mozilla {
  32 namespace hal_impl {
  33
  34 void SetProcessPriority(int aPid, ProcessPriority aPriority) {
  35   if (aPriority == PROCESS_PRIORITY_PARENT_PROCESS) {
  36     // This is the parent process itself, which we do not control.
  37     return;
  38   }
  39
  40   const int32_t intPriority = static_cast<int32_t>(aPriority);
  41   if (intPriority < 0 || intPriority >= NUM_PROCESS_PRIORITY) {
  42     return;
  43   }
  44
  45   auto contentProcType = java::GeckoProcessType::CONTENT();
  46   auto selector =
  47       java::GeckoProcessManager::Selector::New(contentProcType, aPid);
  48   auto priorityLevel = ToJavaPriorityLevel(aPriority);
  49
  50   // To Android, a lower-valued integer is a higher relative priority.
  51   // We take the integer value of the enum and subtract it from the value
  52   // of the highest Gecko priority level to obtain a 0-based indicator of
  53   // the relative priority within the Java PriorityLevel.
  54   const int32_t relativeImportance =
  55       (static_cast<int32_t>(NUM_PROCESS_PRIORITY) - 1) - intPriority;
  56
  57   java::GeckoProcessManager::SetProcessPriority(selector, priorityLevel,
  58                                                 relativeImportance);
  59 }
  60
  61 }  // namespace hal_impl
  62 }  // namespace mozilla