Test dynamic priorities

base/threading/simple_thread.cc

Index: base/threading/simple_thread.cc
diff --git a/base/threading/simple_thread.cc b/base/threading/simple_thread.cc
index 7059ceab76661428a3a4e9f7eb124e524b162ebe..7496962d099f5e8eafa4d6ffbee7a587449e14ca 100644
--- a/base/threading/simple_thread.cc
+++ b/base/threading/simple_thread.cc
@@ -12,15 +12,24 @@
 namespace base {
 
 SimpleThread::SimpleThread(const std::string& name_prefix)
-    : name_prefix_(name_prefix), name_(name_prefix),
-      thread_(), event_(true, false), tid_(0), joined_(false) {
-}
+    : name_prefix_(name_prefix),
+      name_(name_prefix),
+      thread_(),
+      event_(true, false),
+      tid_(0),
+      joined_(false),
+      priority_(options_.priority()) {}
 
 SimpleThread::SimpleThread(const std::string& name_prefix,
                            const Options& options)
-    : name_prefix_(name_prefix), name_(name_prefix), options_(options),
-      thread_(), event_(true, false), tid_(0), joined_(false) {
-}
+    : name_prefix_(name_prefix),
+      name_(name_prefix),
+      options_(options),
+      thread_(),
+      event_(true, false),
+      tid_(0),
+      joined_(false),
+      priority_(options_.priority()) {}
 
 SimpleThread::~SimpleThread() {
   DCHECK(HasBeenStarted()) << "SimpleThread was never started.";
@@ -41,6 +50,14 @@ void SimpleThread::Start() {
   event_.Wait();  // Wait for the thread to complete initialization.
 }
 
+bool SimpleThread::SetThreadPriority(ThreadPriority priority) {
+  if (PlatformThread::SetThreadPriority(tid_, priority)) {
+    priority_ = priority;
+    return true;
+  }
+  return false;
+}
+
 void SimpleThread::Join() {
   DCHECK(HasBeenStarted()) << "Tried to Join a never-started thread.";
   DCHECK(!HasBeenJoined()) << "Tried to Join a thread multiple times.";
@@ -66,6 +83,82 @@ void SimpleThread::ThreadMain() {
   Run();
 }
 
+TestSimpleThread::TestSimpleThread(const PrioritySet& priorities,
+                                   const std::string& name_prefix,
+                                   const Options& options)
+    : SimpleThread(name_prefix, options),
+      priorities_(priorities),
+      dynamic_prio_(false),
+      changed_(false) {
+  CHECK(priorities_.high_prio == priorities_.default_prio ||
+        priorities_.low_prio == priorities_.default_prio);
+  dynamic_prio_ = priorities_.high_prio != priorities_.low_prio;
+}
+
+bool TestSimpleThread::Speedup() {
+  if (dynamic_prio_ && (GetThreadPriority() != priorities_.high_prio)) {
+    SetThreadPriority(priorities_.high_prio);
+    changed_ = true;
+    return true;
+  }
+  return false;
+}
+
+bool TestSimpleThread::Slowdown() {
+  if (dynamic_prio_ && (GetThreadPriority() != priorities_.low_prio)) {
+    SetThreadPriority(priorities_.low_prio);
+    changed_ = true;
+    return true;
+  }
+  return false;
+}
+
+bool TestSimpleThread::Restore() {
+  if (dynamic_prio_ && changed_) {
+    changed_ = false;
+    SetThreadPriority(priorities_.default_prio);
+    // LOG(ERROR) << "\nPRAS:: [" << std::hex << this << "] "
+    //            << GetPrioritySetForDebugging() << ".  Restored to default.";
+    return true;
+  }
+  return false;
+}
+
+std::string GetPriorityString(ThreadPriority prio) {
+  std::string str;
+  if (prio == base::ThreadPriority::BACKGROUND)
+    str = "background";
+  else if (prio == base::ThreadPriority::NORMAL)
+    str = "normal";
+  else if (prio == base::ThreadPriority::DISPLAY)
+    str = "display";
+  else if (prio == base::ThreadPriority::REALTIME_AUDIO)
+    str = "audio";
+  else
+    str = "WRONG";
+
+  return str;
+}
+
+std::string TestSimpleThread::GetPrioritySetForDebugging() {
+  static bool once = true;
+
+  if (once) {
+    std::ostringstream stream;
+    stream << "{ Default = " << GetPriorityString(priorities_.default_prio)
+           << ", Low = " << GetPriorityString(priorities_.low_prio)
+           << ", High = " << GetPriorityString(priorities_.high_prio) << "}";
+    priorities_str_ = stream.str();
+  }
+
+  std::string str = "Current = ";
+  str += GetPriorityString(GetThreadPriority());
+  str += ",  ";
+  str += priorities_str_;
+
+  return str;
+}
+
 DelegateSimpleThread::DelegateSimpleThread(Delegate* delegate,
                                            const std::string& name_prefix)
     : SimpleThread(name_prefix),