base/threading/platform_thread_android.cc

   1 // Copyright (c) 2012 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 #include "base/threading/platform_thread.h"
   6
   7 #include <errno.h>
   8 #include <sys/resource.h>
   9
  10 #include "base/android/jni_android.h"
  11 #include "base/android/thread_utils.h"
  12 #include "base/lazy_instance.h"
  13 #include "base/logging.h"
  14 #include "base/threading/thread_id_name_manager.h"
  15 #include "base/tracked_objects.h"
  16 #include "jni/ThreadUtils_jni.h"
  17
  18 namespace base {
  19
  20 namespace {
  21 int ThreadNiceValue(ThreadPriority priority) {
  22   // These nice values are taken from Android, which uses nice
  23   // values like linux, but defines some preset nice values.
  24   //   Process.THREAD_PRIORITY_AUDIO = -16
  25   //   Process.THREAD_PRIORITY_BACKGROUND = 10
  26   //   Process.THREAD_PRIORITY_DEFAULT = 0;
  27   //   Process.THREAD_PRIORITY_DISPLAY = -4;
  28   //   Process.THREAD_PRIORITY_FOREGROUND = -2;
  29   //   Process.THREAD_PRIORITY_LESS_FAVORABLE = 1;
  30   //   Process.THREAD_PRIORITY_LOWEST = 19;
  31   //   Process.THREAD_PRIORITY_MORE_FAVORABLE = -1;
  32   //   Process.THREAD_PRIORITY_URGENT_AUDIO = -19;
  33   //   Process.THREAD_PRIORITY_URGENT_DISPLAY = -8;
  34   // We use -6 for display, but we may want to split this
  35   // into urgent (-8) and non-urgent (-4).
  36   static const int threadPriorityAudio = -16;
  37   static const int threadPriorityBackground = 10;
  38   static const int threadPriorityDefault = 0;
  39   static const int threadPriorityDisplay = -6;
  40   switch (priority) {
  41     case kThreadPriority_RealtimeAudio:
  42       return threadPriorityAudio;
  43     case kThreadPriority_Background:
  44       return threadPriorityBackground;
  45     case kThreadPriority_Normal:
  46       return threadPriorityDefault;
  47     case kThreadPriority_Display:
  48       return threadPriorityDisplay;
  49     default:
  50       NOTREACHED() << "Unknown priority.";
  51       return 0;
  52   }
  53 }
  54 } // namespace
  55
  56 //static
  57 void PlatformThread::SetThreadPriority(PlatformThreadHandle handle,
  58                                        ThreadPriority priority) {
  59   // On Android, we set the Audio priority through JNI as Audio priority
  60   // will also allow the process to run while it is backgrounded.
  61   if (priority == kThreadPriority_RealtimeAudio) {
  62     JNIEnv* env = base::android::AttachCurrentThread();
  63     Java_ThreadUtils_setThreadPriorityAudio(env, PlatformThread::CurrentId());
  64     return;
  65   }
  66
  67   // setpriority(2) will set a thread's priority if it is passed a tid as
  68   // the 'process identifier', not affecting the rest of the threads in the
  69   // process. Setting this priority will only succeed if the user has been
  70   // granted permission to adjust nice values on the system.
  71   DCHECK_NE(handle.id_, kInvalidThreadId);
  72   int kNiceSetting = ThreadNiceValue(priority);
  73   if (setpriority(PRIO_PROCESS, handle.id_, kNiceSetting))
  74     LOG(ERROR) << "Failed to set nice value of thread to " << kNiceSetting;
  75 }
  76
  77 void PlatformThread::SetName(const char* name) {
  78   ThreadIdNameManager::GetInstance()->SetName(CurrentId(), name);
  79   tracked_objects::ThreadData::InitializeThreadContext(name);
  80 }
  81
  82
  83 void InitThreading() {
  84 }
  85
  86 void InitOnThread() {
  87   // Threads on linux/android may inherit their priority from the thread
  88   // where they were created. This sets all new threads to the default.
  89   PlatformThread::SetThreadPriority(PlatformThread::CurrentHandle(),
  90                                     kThreadPriority_Normal);
  91 }
  92
  93 void TerminateOnThread() {
  94   base::android::DetachFromVM();
  95 }
  96
  97 size_t GetDefaultThreadStackSize(const pthread_attr_t& attributes) {
  98   return 0;
  99 }
 100
 101 bool RegisterThreadUtils(JNIEnv* env) {
 102   return RegisterNativesImpl(env);
 103 }
 104
 105 }  // namespace base