Test dynamic priorities

base/threading/simple_thread.cc

 // Copyright (c) 2010 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/simple_thread.h"
 
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/threading/platform_thread.h"
 #include "base/threading/thread_restrictions.h"
 
 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.";
   DCHECK(HasBeenJoined()) << "SimpleThread destroyed without being Join()ed.";
 }
 
 void SimpleThread::Start() {
   DCHECK(!HasBeenStarted()) << "Tried to Start a thread multiple times.";
   bool success;
   if (options_.priority() == ThreadPriority::NORMAL) {
     success = PlatformThread::Create(options_.stack_size(), this, &thread_);
   } else {
     success = PlatformThread::CreateWithPriority(options_.stack_size(), this,
                                                  &thread_, options_.priority());
   }
   DCHECK(success);
   base::ThreadRestrictions::ScopedAllowWait allow_wait;
   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.";
   PlatformThread::Join(thread_);
   joined_ = true;
 }
 
 bool SimpleThread::HasBeenStarted() {
   base::ThreadRestrictions::ScopedAllowWait allow_wait;
   return event_.IsSignaled();
 }
 
 void SimpleThread::ThreadMain() {
   tid_ = PlatformThread::CurrentId();
   // Construct our full name of the form "name_prefix_/TID".
   name_.push_back('/');
   name_.append(IntToString(tid_));
   PlatformThread::SetName(name_);
 
   // We've initialized our new thread, signal that we're done to Start().
   event_.Signal();
 
   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),
       delegate_(delegate) {
 }
 
 DelegateSimpleThread::DelegateSimpleThread(Delegate* delegate,
                                            const std::string& name_prefix,
                                            const Options& options)
     : SimpleThread(name_prefix, options),
@@ skipping 77 matching lines @@
 
     // A NULL delegate pointer signals us to quit.
     if (!work)
       break;
 
     work->Run();
   }
 }
 
 }  // namespace base