Update //base to chromium 9659b08ea5a34f889dc4166217f438095ddc10d2

base/threading/platform_thread_android.cc

 // Copyright (c) 2012 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/threading/platform_thread.h"
 
 #include <errno.h>
 #include <sys/prctl.h>
 #include <sys/resource.h>
 #include <sys/types.h>
 #include <unistd.h>
 
 #include "base/android/jni_android.h"
 #include "base/android/thread_utils.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/threading/platform_thread_internal_posix.h"
 #include "base/threading/thread_id_name_manager.h"
 #include "base/tracked_objects.h"
 #include "jni/ThreadUtils_jni.h"
 
 namespace base {
 
 namespace internal {
 
-// These nice values are taken from Android, which uses nice values like linux,
-// but defines some preset nice values.
-//   Process.THREAD_PRIORITY_AUDIO = -16
-//   Process.THREAD_PRIORITY_BACKGROUND = 10
-//   Process.THREAD_PRIORITY_DEFAULT = 0;
-//   Process.THREAD_PRIORITY_DISPLAY = -4;
-//   Process.THREAD_PRIORITY_FOREGROUND = -2;
-//   Process.THREAD_PRIORITY_LESS_FAVORABLE = 1;
-//   Process.THREAD_PRIORITY_LOWEST = 19;
-//   Process.THREAD_PRIORITY_MORE_FAVORABLE = -1;
-//   Process.THREAD_PRIORITY_URGENT_AUDIO = -19;
-//   Process.THREAD_PRIORITY_URGENT_DISPLAY = -8;
-// We use -6 for display, but we may want to split this into urgent (-8) and
-// non-urgent (-4).
+// - BACKGROUND is 9 due to it being the nicest value we can use that's still
+// above an Android system threshold that enables heavy throttling starting at
+// 10; we want to be lower-priority than Chrome's other threads without
+// incurring this behavior.
+// - DISPLAY is -6 due to being midway between Android's DISPLAY (-4) and
+// URGENT_DISPLAY (-8).
+// - REALTIME_AUDIO corresponds to Android's THREAD_PRIORITY_AUDIO = -16 value.
 const ThreadPriorityToNiceValuePair kThreadPriorityToNiceValueMap[4] = {
-    {ThreadPriority::BACKGROUND, 10},
+    {ThreadPriority::BACKGROUND, 9},
     {ThreadPriority::NORMAL, 0},
     {ThreadPriority::DISPLAY, -6},
     {ThreadPriority::REALTIME_AUDIO, -16},
 };
 
-bool SetThreadPriorityForPlatform(PlatformThreadHandle handle,
-                                  ThreadPriority priority) {
+bool SetCurrentThreadPriorityForPlatform(ThreadPriority priority) {
   // On Android, we set the Audio priority through JNI as Audio priority
   // will also allow the process to run while it is backgrounded.
   if (priority == ThreadPriority::REALTIME_AUDIO) {
     JNIEnv* env = base::android::AttachCurrentThread();
     Java_ThreadUtils_setThreadPriorityAudio(env, PlatformThread::CurrentId());
     return true;
   }
   return false;
 }
 
-bool GetThreadPriorityForPlatform(PlatformThreadHandle handle,
-                                  ThreadPriority* priority) {
+bool GetCurrentThreadPriorityForPlatform(ThreadPriority* priority) {
+  // See http://crbug.com/505474.
   NOTIMPLEMENTED();
   return false;
 }
 
 }  // namespace internal
 
 void PlatformThread::SetName(const std::string& name) {
   ThreadIdNameManager::GetInstance()->SetName(CurrentId(), name);
   tracked_objects::ThreadData::InitializeThreadContext(name);
 
@@ skipping 10 matching lines @@
     DPLOG(ERROR) << "prctl(PR_SET_NAME)";
 }
 
 
 void InitThreading() {
 }
 
 void InitOnThread() {
   // Threads on linux/android may inherit their priority from the thread
   // where they were created. This sets all new threads to the default.
-  PlatformThread::SetThreadPriority(PlatformThread::CurrentHandle(),
-                                    ThreadPriority::NORMAL);
+  PlatformThread::SetCurrentThreadPriority(ThreadPriority::NORMAL);
 }
 
 void TerminateOnThread() {
   base::android::DetachFromVM();
 }
 
 size_t GetDefaultThreadStackSize(const pthread_attr_t& attributes) {
 #if !defined(ADDRESS_SANITIZER)
   return 0;
 #else
   // AddressSanitizer bloats the stack approximately 2x. Default stack size of
   // 1Mb is not enough for some tests (see http://crbug.com/263749 for example).
   return 2 * (1 << 20);  // 2Mb
 #endif
 }
 
 bool RegisterThreadUtils(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 }  // namespace base