michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim: set ts=8 sts=2 et sw=2 tw=80: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsTimerImpl.h"
michael@0: #include "TimerThread.h"
michael@0: #include "nsAutoPtr.h"
michael@0: #include "nsThreadManager.h"
michael@0: #include "nsThreadUtils.h"
michael@0: #include "plarena.h"
michael@0: #include "pratom.h"
michael@0: #include "GeckoProfiler.h"
michael@0: #include "mozilla/Atomics.h"
michael@0: 
michael@0: using mozilla::Atomic;
michael@0: using mozilla::TimeDuration;
michael@0: using mozilla::TimeStamp;
michael@0: 
michael@0: static Atomic<int32_t>  gGenerator;
michael@0: static TimerThread*     gThread = nullptr;
michael@0: 
michael@0: #ifdef DEBUG_TIMERS
michael@0: 
michael@0: PRLogModuleInfo*
michael@0: GetTimerLog()
michael@0: {
michael@0:   static PRLogModuleInfo *sLog;
michael@0:   if (!sLog)
michael@0:     sLog = PR_NewLogModule("nsTimerImpl");
michael@0:   return sLog;
michael@0: }
michael@0: 
michael@0: #include <math.h>
michael@0: 
michael@0: double nsTimerImpl::sDeltaSumSquared = 0;
michael@0: double nsTimerImpl::sDeltaSum = 0;
michael@0: double nsTimerImpl::sDeltaNum = 0;
michael@0: 
michael@0: static void
michael@0: myNS_MeanAndStdDev(double n, double sumOfValues, double sumOfSquaredValues,
michael@0:                    double *meanResult, double *stdDevResult)
michael@0: {
michael@0:   double mean = 0.0, var = 0.0, stdDev = 0.0;
michael@0:   if (n > 0.0 && sumOfValues >= 0) {
michael@0:     mean = sumOfValues / n;
michael@0:     double temp = (n * sumOfSquaredValues) - (sumOfValues * sumOfValues);
michael@0:     if (temp < 0.0 || n <= 1)
michael@0:       var = 0.0;
michael@0:     else
michael@0:       var = temp / (n * (n - 1));
michael@0:     // for some reason, Windows says sqrt(0.0) is "-1.#J" (?!) so do this:
michael@0:     stdDev = var != 0.0 ? sqrt(var) : 0.0;
michael@0:   }
michael@0:   *meanResult = mean;
michael@0:   *stdDevResult = stdDev;
michael@0: }
michael@0: #endif
michael@0: 
michael@0: namespace {
michael@0: 
michael@0: // TimerEventAllocator is a thread-safe allocator used only for nsTimerEvents.
michael@0: // It's needed to avoid contention over the default allocator lock when
michael@0: // firing timer events (see bug 733277).  The thread-safety is required because
michael@0: // nsTimerEvent objects are allocated on the timer thread, and freed on another
michael@0: // thread.  Because TimerEventAllocator has its own lock, contention over that
michael@0: // lock is limited to the allocation and deallocation of nsTimerEvent objects.
michael@0: //
michael@0: // Because this allocator is layered over PLArenaPool, it never shrinks -- even
michael@0: // "freed" nsTimerEvents aren't truly freed, they're just put onto a free-list
michael@0: // for later recycling.  So the amount of memory consumed will always be equal
michael@0: // to the high-water mark consumption.  But nsTimerEvents are small and it's
michael@0: // unusual to have more than a few hundred of them, so this shouldn't be a
michael@0: // problem in practice.
michael@0: 
michael@0: class TimerEventAllocator
michael@0: {
michael@0: private:
michael@0:   struct FreeEntry {
michael@0:     FreeEntry* mNext;
michael@0:   };
michael@0: 
michael@0:   PLArenaPool mPool;
michael@0:   FreeEntry* mFirstFree;
michael@0:   mozilla::Monitor mMonitor;
michael@0: 
michael@0: public:
michael@0:   TimerEventAllocator()
michael@0:     : mFirstFree(nullptr),
michael@0:       mMonitor("TimerEventAllocator")
michael@0:   {
michael@0:     PL_InitArenaPool(&mPool, "TimerEventPool", 4096, /* align = */ 0);
michael@0:   }
michael@0: 
michael@0:   ~TimerEventAllocator()
michael@0:   {
michael@0:     PL_FinishArenaPool(&mPool);
michael@0:   }
michael@0: 
michael@0:   void* Alloc(size_t aSize);
michael@0:   void Free(void* aPtr);
michael@0: };
michael@0: 
michael@0: } // anonymous namespace
michael@0: 
michael@0: class nsTimerEvent : public nsRunnable {
michael@0: public:
michael@0:   NS_IMETHOD Run();
michael@0: 
michael@0:   nsTimerEvent()
michael@0:     : mTimer()
michael@0:     , mGeneration(0)
michael@0:    {
michael@0:     MOZ_COUNT_CTOR(nsTimerEvent);
michael@0: 
michael@0:     MOZ_ASSERT(gThread->IsOnTimerThread(),
michael@0:                "nsTimer must always be allocated on the timer thread");
michael@0: 
michael@0:     sAllocatorUsers++;
michael@0:   }
michael@0: 
michael@0: #ifdef DEBUG_TIMERS
michael@0:   TimeStamp mInitTime;
michael@0: #endif
michael@0: 
michael@0:   static void Init();
michael@0:   static void Shutdown();
michael@0:   static void DeleteAllocatorIfNeeded();
michael@0: 
michael@0:   static void* operator new(size_t size) CPP_THROW_NEW {
michael@0:     return sAllocator->Alloc(size);
michael@0:   }
michael@0:   void operator delete(void* p) {
michael@0:     sAllocator->Free(p);
michael@0:     DeleteAllocatorIfNeeded();
michael@0:   }
michael@0: 
michael@0:   already_AddRefed<nsTimerImpl> ForgetTimer()
michael@0:   {
michael@0:     return mTimer.forget();
michael@0:   }
michael@0: 
michael@0:   void SetTimer(already_AddRefed<nsTimerImpl> aTimer)
michael@0:   {
michael@0:     mTimer = aTimer;
michael@0:     mGeneration = mTimer->GetGeneration();
michael@0:   }
michael@0: 
michael@0: private:
michael@0:   ~nsTimerEvent() {
michael@0:     MOZ_COUNT_DTOR(nsTimerEvent);
michael@0: 
michael@0:     MOZ_ASSERT(!sCanDeleteAllocator || sAllocatorUsers > 0,
michael@0:                "This will result in us attempting to deallocate the nsTimerEvent allocator twice");
michael@0:     sAllocatorUsers--;
michael@0:   }
michael@0: 
michael@0:   nsRefPtr<nsTimerImpl> mTimer;
michael@0:   int32_t      mGeneration;
michael@0: 
michael@0:   static TimerEventAllocator* sAllocator;
michael@0:   static Atomic<int32_t> sAllocatorUsers;
michael@0:   static bool sCanDeleteAllocator;
michael@0: };
michael@0: 
michael@0: TimerEventAllocator* nsTimerEvent::sAllocator = nullptr;
michael@0: Atomic<int32_t> nsTimerEvent::sAllocatorUsers;
michael@0: bool nsTimerEvent::sCanDeleteAllocator = false;
michael@0: 
michael@0: namespace {
michael@0: 
michael@0: void* TimerEventAllocator::Alloc(size_t aSize)
michael@0: {
michael@0:   MOZ_ASSERT(aSize == sizeof(nsTimerEvent));
michael@0: 
michael@0:   mozilla::MonitorAutoLock lock(mMonitor);
michael@0: 
michael@0:   void* p;
michael@0:   if (mFirstFree) {
michael@0:     p = mFirstFree;
michael@0:     mFirstFree = mFirstFree->mNext;
michael@0:   }
michael@0:   else {
michael@0:     PL_ARENA_ALLOCATE(p, &mPool, aSize);
michael@0:     if (!p)
michael@0:       return nullptr;
michael@0:   }
michael@0: 
michael@0:   return p;
michael@0: }
michael@0: 
michael@0: void TimerEventAllocator::Free(void* aPtr)
michael@0: {
michael@0:   mozilla::MonitorAutoLock lock(mMonitor);
michael@0: 
michael@0:   FreeEntry* entry = reinterpret_cast<FreeEntry*>(aPtr);
michael@0: 
michael@0:   entry->mNext = mFirstFree;
michael@0:   mFirstFree = entry;
michael@0: }
michael@0: 
michael@0: } // anonymous namespace
michael@0: 
michael@0: NS_IMPL_QUERY_INTERFACE(nsTimerImpl, nsITimer)
michael@0: NS_IMPL_ADDREF(nsTimerImpl)
michael@0: 
michael@0: NS_IMETHODIMP_(MozExternalRefCountType) nsTimerImpl::Release(void)
michael@0: {
michael@0:   nsrefcnt count;
michael@0: 
michael@0:   MOZ_ASSERT(int32_t(mRefCnt) > 0, "dup release");
michael@0:   count = --mRefCnt;
michael@0:   NS_LOG_RELEASE(this, count, "nsTimerImpl");
michael@0:   if (count == 0) {
michael@0:     mRefCnt = 1; /* stabilize */
michael@0: 
michael@0:     /* enable this to find non-threadsafe destructors: */
michael@0:     /* NS_ASSERT_OWNINGTHREAD(nsTimerImpl); */
michael@0:     delete this;
michael@0:     return 0;
michael@0:   }
michael@0: 
michael@0:   // If only one reference remains, and mArmed is set, then the ref must be
michael@0:   // from the TimerThread::mTimers array, so we Cancel this timer to remove
michael@0:   // the mTimers element, and return 0 if Cancel in fact disarmed the timer.
michael@0:   //
michael@0:   // We use an inlined version of nsTimerImpl::Cancel here to check for the
michael@0:   // NS_ERROR_NOT_AVAILABLE code returned by gThread->RemoveTimer when this
michael@0:   // timer is not found in the mTimers array -- i.e., when the timer was not
michael@0:   // in fact armed once we acquired TimerThread::mLock, in spite of mArmed
michael@0:   // being true here.  That can happen if the armed timer is being fired by
michael@0:   // TimerThread::Run as we race and test mArmed just before it is cleared by
michael@0:   // the timer thread.  If the RemoveTimer call below doesn't find this timer
michael@0:   // in the mTimers array, then the last ref to this timer is held manually
michael@0:   // and temporarily by the TimerThread, so we should fall through to the
michael@0:   // final return and return 1, not 0.
michael@0:   //
michael@0:   // The original version of this thread-based timer code kept weak refs from
michael@0:   // TimerThread::mTimers, removing this timer's weak ref in the destructor,
michael@0:   // but that leads to double-destructions in the race described above, and
michael@0:   // adding mArmed doesn't help, because destructors can't be deferred, once
michael@0:   // begun.  But by combining reference-counting and a specialized Release
michael@0:   // method with "is this timer still in the mTimers array once we acquire
michael@0:   // the TimerThread's lock" testing, we defer destruction until we're sure
michael@0:   // that only one thread has its hot little hands on this timer.
michael@0:   //
michael@0:   // Note that both approaches preclude a timer creator, and everyone else
michael@0:   // except the TimerThread who might have a strong ref, from dropping all
michael@0:   // their strong refs without implicitly canceling the timer.  Timers need
michael@0:   // non-mTimers-element strong refs to stay alive.
michael@0: 
michael@0:   if (count == 1 && mArmed) {
michael@0:     mCanceled = true;
michael@0: 
michael@0:     MOZ_ASSERT(gThread, "Armed timer exists after the thread timer stopped.");
michael@0:     if (NS_SUCCEEDED(gThread->RemoveTimer(this)))
michael@0:       return 0;
michael@0:   }
michael@0: 
michael@0:   return count;
michael@0: }
michael@0: 
michael@0: nsTimerImpl::nsTimerImpl() :
michael@0:   mClosure(nullptr),
michael@0:   mCallbackType(CALLBACK_TYPE_UNKNOWN),
michael@0:   mFiring(false),
michael@0:   mArmed(false),
michael@0:   mCanceled(false),
michael@0:   mGeneration(0),
michael@0:   mDelay(0)
michael@0: {
michael@0:   // XXXbsmedberg: shouldn't this be in Init()?
michael@0:   mEventTarget = static_cast<nsIEventTarget*>(NS_GetCurrentThread());
michael@0: 
michael@0:   mCallback.c = nullptr;
michael@0: }
michael@0: 
michael@0: nsTimerImpl::~nsTimerImpl()
michael@0: {
michael@0:   ReleaseCallback();
michael@0: }
michael@0: 
michael@0: //static
michael@0: nsresult
michael@0: nsTimerImpl::Startup()
michael@0: {
michael@0:   nsresult rv;
michael@0: 
michael@0:   nsTimerEvent::Init();
michael@0: 
michael@0:   gThread = new TimerThread();
michael@0:   if (!gThread) return NS_ERROR_OUT_OF_MEMORY;
michael@0: 
michael@0:   NS_ADDREF(gThread);
michael@0:   rv = gThread->InitLocks();
michael@0: 
michael@0:   if (NS_FAILED(rv)) {
michael@0:     NS_RELEASE(gThread);
michael@0:   }
michael@0: 
michael@0:   return rv;
michael@0: }
michael@0: 
michael@0: void nsTimerImpl::Shutdown()
michael@0: {
michael@0: #ifdef DEBUG_TIMERS
michael@0:   if (PR_LOG_TEST(GetTimerLog(), PR_LOG_DEBUG)) {
michael@0:     double mean = 0, stddev = 0;
michael@0:     myNS_MeanAndStdDev(sDeltaNum, sDeltaSum, sDeltaSumSquared, &mean, &stddev);
michael@0: 
michael@0:     PR_LOG(GetTimerLog(), PR_LOG_DEBUG, ("sDeltaNum = %f, sDeltaSum = %f, sDeltaSumSquared = %f\n", sDeltaNum, sDeltaSum, sDeltaSumSquared));
michael@0:     PR_LOG(GetTimerLog(), PR_LOG_DEBUG, ("mean: %fms, stddev: %fms\n", mean, stddev));
michael@0:   }
michael@0: #endif
michael@0: 
michael@0:   if (!gThread)
michael@0:     return;
michael@0: 
michael@0:   gThread->Shutdown();
michael@0:   NS_RELEASE(gThread);
michael@0: 
michael@0:   nsTimerEvent::Shutdown();
michael@0: }
michael@0: 
michael@0: 
michael@0: nsresult nsTimerImpl::InitCommon(uint32_t aType, uint32_t aDelay)
michael@0: {
michael@0:   nsresult rv;
michael@0: 
michael@0:   if (NS_WARN_IF(!gThread))
michael@0:     return NS_ERROR_NOT_INITIALIZED;
michael@0:   if (!mEventTarget) {
michael@0:     NS_ERROR("mEventTarget is NULL");
michael@0:     return NS_ERROR_NOT_INITIALIZED;
michael@0:   }
michael@0: 
michael@0:   rv = gThread->Init();
michael@0:   if (NS_WARN_IF(NS_FAILED(rv)))
michael@0:     return rv;
michael@0: 
michael@0:   /**
michael@0:    * In case of re-Init, both with and without a preceding Cancel, clear the
michael@0:    * mCanceled flag and assign a new mGeneration.  But first, remove any armed
michael@0:    * timer from the timer thread's list.
michael@0:    *
michael@0:    * If we are racing with the timer thread to remove this timer and we lose,
michael@0:    * the RemoveTimer call made here will fail to find this timer in the timer
michael@0:    * thread's list, and will return false harmlessly.  We test mArmed here to
michael@0:    * avoid the small overhead in RemoveTimer of locking the timer thread and
michael@0:    * checking its list for this timer.  It's safe to test mArmed even though
michael@0:    * it might be cleared on another thread in the next cycle (or even already
michael@0:    * be cleared by another CPU whose store hasn't reached our CPU's cache),
michael@0:    * because RemoveTimer is idempotent.
michael@0:    */
michael@0:   if (mArmed)
michael@0:     gThread->RemoveTimer(this);
michael@0:   mCanceled = false;
michael@0:   mTimeout = TimeStamp();
michael@0:   mGeneration = gGenerator++;
michael@0: 
michael@0:   mType = (uint8_t)aType;
michael@0:   SetDelayInternal(aDelay);
michael@0: 
michael@0:   return gThread->AddTimer(this);
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP nsTimerImpl::InitWithFuncCallback(nsTimerCallbackFunc aFunc,
michael@0:                                                 void *aClosure,
michael@0:                                                 uint32_t aDelay,
michael@0:                                                 uint32_t aType)
michael@0: {
michael@0:   if (NS_WARN_IF(!aFunc))
michael@0:     return NS_ERROR_INVALID_ARG;
michael@0:   
michael@0:   ReleaseCallback();
michael@0:   mCallbackType = CALLBACK_TYPE_FUNC;
michael@0:   mCallback.c = aFunc;
michael@0:   mClosure = aClosure;
michael@0: 
michael@0:   return InitCommon(aType, aDelay);
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP nsTimerImpl::InitWithCallback(nsITimerCallback *aCallback,
michael@0:                                             uint32_t aDelay,
michael@0:                                             uint32_t aType)
michael@0: {
michael@0:   if (NS_WARN_IF(!aCallback))
michael@0:     return NS_ERROR_INVALID_ARG;
michael@0: 
michael@0:   ReleaseCallback();
michael@0:   mCallbackType = CALLBACK_TYPE_INTERFACE;
michael@0:   mCallback.i = aCallback;
michael@0:   NS_ADDREF(mCallback.i);
michael@0: 
michael@0:   return InitCommon(aType, aDelay);
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP nsTimerImpl::Init(nsIObserver *aObserver,
michael@0:                                 uint32_t aDelay,
michael@0:                                 uint32_t aType)
michael@0: {
michael@0:   if (NS_WARN_IF(!aObserver))
michael@0:     return NS_ERROR_INVALID_ARG;
michael@0: 
michael@0:   ReleaseCallback();
michael@0:   mCallbackType = CALLBACK_TYPE_OBSERVER;
michael@0:   mCallback.o = aObserver;
michael@0:   NS_ADDREF(mCallback.o);
michael@0: 
michael@0:   return InitCommon(aType, aDelay);
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP nsTimerImpl::Cancel()
michael@0: {
michael@0:   mCanceled = true;
michael@0: 
michael@0:   if (gThread)
michael@0:     gThread->RemoveTimer(this);
michael@0: 
michael@0:   ReleaseCallback();
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP nsTimerImpl::SetDelay(uint32_t aDelay)
michael@0: {
michael@0:   if (mCallbackType == CALLBACK_TYPE_UNKNOWN && mType == TYPE_ONE_SHOT) {
michael@0:     // This may happen if someone tries to re-use a one-shot timer
michael@0:     // by re-setting delay instead of reinitializing the timer.
michael@0:     NS_ERROR("nsITimer->SetDelay() called when the "
michael@0:              "one-shot timer is not set up.");
michael@0:     return NS_ERROR_NOT_INITIALIZED;
michael@0:   }
michael@0: 
michael@0:   // If we're already repeating precisely, update mTimeout now so that the
michael@0:   // new delay takes effect in the future.
michael@0:   if (!mTimeout.IsNull() && mType == TYPE_REPEATING_PRECISE)
michael@0:     mTimeout = TimeStamp::Now();
michael@0: 
michael@0:   SetDelayInternal(aDelay);
michael@0: 
michael@0:   if (!mFiring && gThread)
michael@0:     gThread->TimerDelayChanged(this);
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP nsTimerImpl::GetDelay(uint32_t* aDelay)
michael@0: {
michael@0:   *aDelay = mDelay;
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP nsTimerImpl::SetType(uint32_t aType)
michael@0: {
michael@0:   mType = (uint8_t)aType;
michael@0:   // XXX if this is called, we should change the actual type.. this could effect
michael@0:   // repeating timers.  we need to ensure in Fire() that if mType has changed
michael@0:   // during the callback that we don't end up with the timer in the queue twice.
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP nsTimerImpl::GetType(uint32_t* aType)
michael@0: {
michael@0:   *aType = mType;
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: NS_IMETHODIMP nsTimerImpl::GetClosure(void** aClosure)
michael@0: {
michael@0:   *aClosure = mClosure;
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: NS_IMETHODIMP nsTimerImpl::GetCallback(nsITimerCallback **aCallback)
michael@0: {
michael@0:   if (mCallbackType == CALLBACK_TYPE_INTERFACE)
michael@0:     NS_IF_ADDREF(*aCallback = mCallback.i);
michael@0:   else if (mTimerCallbackWhileFiring)
michael@0:     NS_ADDREF(*aCallback = mTimerCallbackWhileFiring);
michael@0:   else
michael@0:     *aCallback = nullptr;
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: NS_IMETHODIMP nsTimerImpl::GetTarget(nsIEventTarget** aTarget)
michael@0: {
michael@0:   NS_IF_ADDREF(*aTarget = mEventTarget);
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: NS_IMETHODIMP nsTimerImpl::SetTarget(nsIEventTarget* aTarget)
michael@0: {
michael@0:   if (NS_WARN_IF(mCallbackType != CALLBACK_TYPE_UNKNOWN))
michael@0:     return NS_ERROR_ALREADY_INITIALIZED;
michael@0: 
michael@0:   if (aTarget)
michael@0:     mEventTarget = aTarget;
michael@0:   else
michael@0:     mEventTarget = static_cast<nsIEventTarget*>(NS_GetCurrentThread());
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: void nsTimerImpl::Fire()
michael@0: {
michael@0:   if (mCanceled)
michael@0:     return;
michael@0: 
michael@0:   PROFILER_LABEL("Timer", "Fire");
michael@0: 
michael@0: #ifdef MOZ_TASK_TRACER
michael@0:   mozilla::tasktracer::AutoRunFakeTracedTask runTracedTask(mTracedTask);
michael@0: #endif
michael@0: 
michael@0: #ifdef DEBUG_TIMERS
michael@0:   TimeStamp now = TimeStamp::Now();
michael@0:   if (PR_LOG_TEST(GetTimerLog(), PR_LOG_DEBUG)) {
michael@0:     TimeDuration   a = now - mStart; // actual delay in intervals
michael@0:     TimeDuration   b = TimeDuration::FromMilliseconds(mDelay); // expected delay in intervals
michael@0:     TimeDuration   delta = (a > b) ? a - b : b - a;
michael@0:     uint32_t       d = delta.ToMilliseconds(); // delta in ms
michael@0:     sDeltaSum += d;
michael@0:     sDeltaSumSquared += double(d) * double(d);
michael@0:     sDeltaNum++;
michael@0: 
michael@0:     PR_LOG(GetTimerLog(), PR_LOG_DEBUG, ("[this=%p] expected delay time %4ums\n", this, mDelay));
michael@0:     PR_LOG(GetTimerLog(), PR_LOG_DEBUG, ("[this=%p] actual delay time   %fms\n", this, a.ToMilliseconds()));
michael@0:     PR_LOG(GetTimerLog(), PR_LOG_DEBUG, ("[this=%p] (mType is %d)       -------\n", this, mType));
michael@0:     PR_LOG(GetTimerLog(), PR_LOG_DEBUG, ("[this=%p]     delta           %4dms\n", this, (a > b) ? (int32_t)d : -(int32_t)d));
michael@0: 
michael@0:     mStart = mStart2;
michael@0:     mStart2 = TimeStamp();
michael@0:   }
michael@0: #endif
michael@0: 
michael@0:   TimeStamp timeout = mTimeout;
michael@0:   if (IsRepeatingPrecisely()) {
michael@0:     // Precise repeating timers advance mTimeout by mDelay without fail before
michael@0:     // calling Fire().
michael@0:     timeout -= TimeDuration::FromMilliseconds(mDelay);
michael@0:   }
michael@0: 
michael@0:   if (mCallbackType == CALLBACK_TYPE_INTERFACE)
michael@0:     mTimerCallbackWhileFiring = mCallback.i;
michael@0:   mFiring = true;
michael@0: 
michael@0:   // Handle callbacks that re-init the timer, but avoid leaking.
michael@0:   // See bug 330128.
michael@0:   CallbackUnion callback = mCallback;
michael@0:   unsigned callbackType = mCallbackType;
michael@0:   if (callbackType == CALLBACK_TYPE_INTERFACE)
michael@0:     NS_ADDREF(callback.i);
michael@0:   else if (callbackType == CALLBACK_TYPE_OBSERVER)
michael@0:     NS_ADDREF(callback.o);
michael@0:   ReleaseCallback();
michael@0: 
michael@0:   switch (callbackType) {
michael@0:     case CALLBACK_TYPE_FUNC:
michael@0:       callback.c(this, mClosure);
michael@0:       break;
michael@0:     case CALLBACK_TYPE_INTERFACE:
michael@0:       callback.i->Notify(this);
michael@0:       break;
michael@0:     case CALLBACK_TYPE_OBSERVER:
michael@0:       callback.o->Observe(static_cast<nsITimer*>(this),
michael@0:                           NS_TIMER_CALLBACK_TOPIC,
michael@0:                           nullptr);
michael@0:       break;
michael@0:     default:;
michael@0:   }
michael@0: 
michael@0:   // If the callback didn't re-init the timer, and it's not a one-shot timer,
michael@0:   // restore the callback state.
michael@0:   if (mCallbackType == CALLBACK_TYPE_UNKNOWN &&
michael@0:       mType != TYPE_ONE_SHOT && !mCanceled) {
michael@0:     mCallback = callback;
michael@0:     mCallbackType = callbackType;
michael@0:   } else {
michael@0:     // The timer was a one-shot, or the callback was reinitialized.
michael@0:     if (callbackType == CALLBACK_TYPE_INTERFACE)
michael@0:       NS_RELEASE(callback.i);
michael@0:     else if (callbackType == CALLBACK_TYPE_OBSERVER)
michael@0:       NS_RELEASE(callback.o);
michael@0:   }
michael@0: 
michael@0:   mFiring = false;
michael@0:   mTimerCallbackWhileFiring = nullptr;
michael@0: 
michael@0: #ifdef DEBUG_TIMERS
michael@0:   if (PR_LOG_TEST(GetTimerLog(), PR_LOG_DEBUG)) {
michael@0:     PR_LOG(GetTimerLog(), PR_LOG_DEBUG,
michael@0:            ("[this=%p] Took %fms to fire timer callback\n",
michael@0:             this, (TimeStamp::Now() - now).ToMilliseconds()));
michael@0:   }
michael@0: #endif
michael@0: 
michael@0:   // Reschedule repeating timers, except REPEATING_PRECISE which already did
michael@0:   // that in PostTimerEvent, but make sure that we aren't armed already (which
michael@0:   // can happen if the callback reinitialized the timer).
michael@0:   if (IsRepeating() && mType != TYPE_REPEATING_PRECISE && !mArmed) {
michael@0:     if (mType == TYPE_REPEATING_SLACK)
michael@0:       SetDelayInternal(mDelay); // force mTimeout to be recomputed.  For
michael@0:                                 // REPEATING_PRECISE_CAN_SKIP timers this has
michael@0:                                 // already happened.
michael@0:     if (gThread)
michael@0:       gThread->AddTimer(this);
michael@0:   }
michael@0: }
michael@0: 
michael@0: void nsTimerEvent::Init()
michael@0: {
michael@0:   sAllocator = new TimerEventAllocator();
michael@0: }
michael@0: 
michael@0: void nsTimerEvent::Shutdown()
michael@0: {
michael@0:   sCanDeleteAllocator = true;
michael@0:   DeleteAllocatorIfNeeded();
michael@0: }
michael@0: 
michael@0: void nsTimerEvent::DeleteAllocatorIfNeeded()
michael@0: {
michael@0:   if (sCanDeleteAllocator && sAllocatorUsers == 0) {
michael@0:     delete sAllocator;
michael@0:     sAllocator = nullptr;
michael@0:   }
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP nsTimerEvent::Run()
michael@0: {
michael@0:   if (mGeneration != mTimer->GetGeneration())
michael@0:     return NS_OK;
michael@0: 
michael@0: #ifdef DEBUG_TIMERS
michael@0:   if (PR_LOG_TEST(GetTimerLog(), PR_LOG_DEBUG)) {
michael@0:     TimeStamp now = TimeStamp::Now();
michael@0:     PR_LOG(GetTimerLog(), PR_LOG_DEBUG,
michael@0:            ("[this=%p] time between PostTimerEvent() and Fire(): %fms\n",
michael@0:             this, (now - mInitTime).ToMilliseconds()));
michael@0:   }
michael@0: #endif
michael@0: 
michael@0:   mTimer->Fire();
michael@0:   // Since nsTimerImpl is not thread-safe, we should release |mTimer|
michael@0:   // here in the target thread to avoid race condition. Otherwise,
michael@0:   // ~nsTimerEvent() which calls nsTimerImpl::Release() could run in the
michael@0:   // timer thread and result in race condition.
michael@0:   mTimer = nullptr;
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: already_AddRefed<nsTimerImpl>
michael@0: nsTimerImpl::PostTimerEvent(already_AddRefed<nsTimerImpl> aTimerRef)
michael@0: {
michael@0:   nsRefPtr<nsTimerImpl> timer(aTimerRef);
michael@0:   if (!timer->mEventTarget) {
michael@0:     NS_ERROR("Attempt to post timer event to NULL event target");
michael@0:     return timer.forget();
michael@0:   }
michael@0: 
michael@0:   // XXX we may want to reuse this nsTimerEvent in the case of repeating timers.
michael@0: 
michael@0:   // Since TimerThread addref'd 'timer' for us, we don't need to addref here.
michael@0:   // We will release either in ~nsTimerEvent(), or pass the reference back to
michael@0:   // the caller. We need to copy the generation number from this timer into the
michael@0:   // event, so we can avoid firing a timer that was re-initialized after being
michael@0:   // canceled.
michael@0: 
michael@0:   // Note: We override operator new for this class, and the override is
michael@0:   // fallible!
michael@0:   nsRefPtr<nsTimerEvent> event = new nsTimerEvent;
michael@0:   if (!event)
michael@0:     return timer.forget();
michael@0: 
michael@0: #ifdef DEBUG_TIMERS
michael@0:   if (PR_LOG_TEST(GetTimerLog(), PR_LOG_DEBUG)) {
michael@0:     event->mInitTime = TimeStamp::Now();
michael@0:   }
michael@0: #endif
michael@0: 
michael@0:   // If this is a repeating precise timer, we need to calculate the time for
michael@0:   // the next timer to fire before we make the callback.
michael@0:   if (timer->IsRepeatingPrecisely()) {
michael@0:     timer->SetDelayInternal(timer->mDelay);
michael@0: 
michael@0:     // But only re-arm REPEATING_PRECISE timers.
michael@0:     if (gThread && timer->mType == TYPE_REPEATING_PRECISE) {
michael@0:       nsresult rv = gThread->AddTimer(timer);
michael@0:       if (NS_FAILED(rv)) {
michael@0:         return timer.forget();
michael@0:       }
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   nsIEventTarget* target = timer->mEventTarget;
michael@0:   event->SetTimer(timer.forget());
michael@0: 
michael@0:   nsresult rv = target->Dispatch(event, NS_DISPATCH_NORMAL);
michael@0:   if (NS_FAILED(rv)) {
michael@0:     timer = event->ForgetTimer();
michael@0:     if (gThread) {
michael@0:       gThread->RemoveTimer(timer);
michael@0:     }
michael@0:     return timer.forget();
michael@0:   }
michael@0: 
michael@0:   return nullptr;
michael@0: }
michael@0: 
michael@0: void nsTimerImpl::SetDelayInternal(uint32_t aDelay)
michael@0: {
michael@0:   TimeDuration delayInterval = TimeDuration::FromMilliseconds(aDelay);
michael@0: 
michael@0:   mDelay = aDelay;
michael@0: 
michael@0:   TimeStamp now = TimeStamp::Now();
michael@0:   if (mTimeout.IsNull() || mType != TYPE_REPEATING_PRECISE)
michael@0:     mTimeout = now;
michael@0: 
michael@0:   mTimeout += delayInterval;
michael@0: 
michael@0: #ifdef DEBUG_TIMERS
michael@0:   if (PR_LOG_TEST(GetTimerLog(), PR_LOG_DEBUG)) {
michael@0:     if (mStart.IsNull())
michael@0:       mStart = now;
michael@0:     else
michael@0:       mStart2 = now;
michael@0:   }
michael@0: #endif
michael@0: }
michael@0: 
michael@0: // NOT FOR PUBLIC CONSUMPTION!
michael@0: nsresult
michael@0: NS_NewTimer(nsITimer* *aResult, nsTimerCallbackFunc aCallback, void *aClosure,
michael@0:             uint32_t aDelay, uint32_t aType)
michael@0: {
michael@0:     nsTimerImpl* timer = new nsTimerImpl();
michael@0:     if (timer == nullptr)
michael@0:         return NS_ERROR_OUT_OF_MEMORY;
michael@0:     NS_ADDREF(timer);
michael@0: 
michael@0:     nsresult rv = timer->InitWithFuncCallback(aCallback, aClosure, 
michael@0:                                               aDelay, aType);
michael@0:     if (NS_FAILED(rv)) {
michael@0:         NS_RELEASE(timer);
michael@0:         return rv;
michael@0:     }
michael@0: 
michael@0:     *aResult = timer;
michael@0:     return NS_OK;
michael@0: }