X-Git-Url: http://plrg.eecs.uci.edu/git/?p=folly.git;a=blobdiff_plain;f=folly%2Fio%2Fasync%2FEventBase.cpp;h=c1ed73365413b866f367d2b4d5504012cb6dfb72;hp=7bfc221368921f49b0e3cae3eeae7842ec635c69;hb=bda67fde120837b77ddab74f23abcb22ae5b3029;hpb=35ed5364f1ba809d6d103c98c03ae951aab3bc05 diff --git a/folly/io/async/EventBase.cpp b/folly/io/async/EventBase.cpp index 7bfc2213..c1ed7336 100644 --- a/folly/io/async/EventBase.cpp +++ b/folly/io/async/EventBase.cpp @@ -1,5 +1,5 @@ /* - * Copyright 2014 Facebook, Inc. + * Copyright 2017 Facebook, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. @@ -20,52 +20,29 @@ #include -#include -#include - -#include #include -#include -#include - -namespace { - -using folly::Cob; -using folly::EventBase; -template -class FunctionLoopCallback : public EventBase::LoopCallback { - public: - explicit FunctionLoopCallback(Cob&& function) - : function_(std::move(function)) {} - - explicit FunctionLoopCallback(const Cob& function) - : function_(function) {} - - virtual void runLoopCallback() noexcept { - function_(); - delete this; - } +#include +#include +#include - private: - Callback function_; -}; - -} +#include +#include +#include +#include +#include +#include namespace folly { -const int kNoFD = -1; - /* * EventBase::FunctionRunner */ class EventBase::FunctionRunner - : public NotificationQueue>::Consumer { + : public NotificationQueue::Consumer { public: - void messageAvailable(std::pair&& msg) { - + void messageAvailable(Func&& msg) noexcept override { // In libevent2, internal events do not break the loop. // Most users would expect loop(), followed by runInEventBaseThread(), // to break the loop and check if it should exit or not. @@ -74,58 +51,15 @@ class EventBase::FunctionRunner // stop_ flag as well as runInLoop callbacks, etc. event_base_loopbreak(getEventBase()->evb_); - if (msg.first == nullptr && msg.second == nullptr) { + if (!msg) { // terminateLoopSoon() sends a null message just to // wake up the loop. We can ignore these messages. return; } - - // If function is nullptr, just log and move on - if (!msg.first) { - LOG(ERROR) << "nullptr callback registered to be run in " - << "event base thread"; - return; - } - - // The function should never throw an exception, because we have no - // way of knowing what sort of error handling to perform. - // - // If it does throw, log a message and abort the program. - try { - msg.first(msg.second); - } catch (const std::exception& ex) { - LOG(ERROR) << "runInEventBaseThread() function threw a " - << typeid(ex).name() << " exception: " << ex.what(); - abort(); - } catch (...) { - LOG(ERROR) << "runInEventBaseThread() function threw an exception"; - abort(); - } + msg(); } }; -/* - * EventBase::CobTimeout methods - */ - -void EventBase::CobTimeout::timeoutExpired() noexcept { - // For now, we just swallow any exceptions that the callback threw. - try { - cob_(); - } catch (const std::exception& ex) { - LOG(ERROR) << "EventBase::runAfterDelay() callback threw " - << typeid(ex).name() << " exception: " << ex.what(); - } catch (...) { - LOG(ERROR) << "EventBase::runAfterDelay() callback threw non-exception " - << "type"; - } - - // The CobTimeout object was allocated on the heap by runAfterDelay(), - // so delete it now that the it has fired. - delete this; -} - - // The interface used to libevent is not thread-safe. Calls to // event_init() and event_base_free() directly modify an internal // global 'current_base', so a mutex is required to protect this. @@ -139,66 +73,92 @@ static std::mutex libevent_mutex_; * EventBase methods */ -EventBase::EventBase() +EventBase::EventBase(bool enableTimeMeasurement) : runOnceCallbacks_(nullptr) , stop_(false) - , loopThread_(0) + , loopThread_() , queue_(nullptr) , fnRunner_(nullptr) , maxLatency_(0) - , avgLoopTime_(2000000) + , avgLoopTime_(std::chrono::seconds(2)) , maxLatencyLoopTime_(avgLoopTime_) - , nextLoopCnt_(-40) // Early wrap-around so bugs will manifest soon + , enableTimeMeasurement_(enableTimeMeasurement) + , nextLoopCnt_(uint64_t(-40)) // Early wrap-around so bugs will manifest soon , latestLoopCnt_(nextLoopCnt_) - , startWork_(0) + , startWork_() , observer_(nullptr) - , observerSampleCount_(0) { + , observerSampleCount_(0) + , executionObserver_(nullptr) { + struct event ev; { std::lock_guard lock(libevent_mutex_); // The value 'current_base' (libevent 1) or // 'event_global_current_base_' (libevent 2) is filled in by event_set(), // allowing examination of its value without an explicit reference here. - // If ev.ev_base is NULL, then event_init() must be called, otherwise + // If ev.ev_base is nullptr, then event_init() must be called, otherwise // call event_base_new(). - struct event ev; event_set(&ev, 0, 0, nullptr, nullptr); - evb_ = (ev.ev_base) ? event_base_new() : event_init(); + if (!ev.ev_base) { + evb_ = event_init(); + } + } + + if (ev.ev_base) { + evb_ = event_base_new(); } + if (UNLIKELY(evb_ == nullptr)) { LOG(ERROR) << "EventBase(): Failed to init event base."; folly::throwSystemError("error in EventBase::EventBase()"); } VLOG(5) << "EventBase(): Created."; initNotificationQueue(); - RequestContext::getStaticContext(); } // takes ownership of the event_base -EventBase::EventBase(event_base* evb) +EventBase::EventBase(event_base* evb, bool enableTimeMeasurement) : runOnceCallbacks_(nullptr) , stop_(false) - , loopThread_(0) + , loopThread_() , evb_(evb) , queue_(nullptr) , fnRunner_(nullptr) , maxLatency_(0) - , avgLoopTime_(2000000) + , avgLoopTime_(std::chrono::seconds(2)) , maxLatencyLoopTime_(avgLoopTime_) - , nextLoopCnt_(-40) // Early wrap-around so bugs will manifest soon + , enableTimeMeasurement_(enableTimeMeasurement) + , nextLoopCnt_(uint64_t(-40)) // Early wrap-around so bugs will manifest soon , latestLoopCnt_(nextLoopCnt_) - , startWork_(0) + , startWork_() , observer_(nullptr) - , observerSampleCount_(0) { + , observerSampleCount_(0) + , executionObserver_(nullptr) { if (UNLIKELY(evb_ == nullptr)) { LOG(ERROR) << "EventBase(): Pass nullptr as event base."; throw std::invalid_argument("EventBase(): event base cannot be nullptr"); } initNotificationQueue(); - RequestContext::getStaticContext(); } EventBase::~EventBase() { + std::future virtualEventBaseDestroyFuture; + if (virtualEventBase_) { + virtualEventBaseDestroyFuture = virtualEventBase_->destroy(); + } + + // Keep looping until all keep-alive handles are released. Each keep-alive + // handle signals that some external code will still schedule some work on + // this EventBase (so it's not safe to destroy it). + while (loopKeepAliveCount() > 0) { + applyLoopKeepAlive(); + loopOnce(); + } + + if (virtualEventBaseDestroyFuture.valid()) { + virtualEventBaseDestroyFuture.get(); + } + // Call all destruction callbacks, before we start cleaning up our state. while (!onDestructionCallbacks_.empty()) { LoopCallback* callback = &onDestructionCallbacks_.front(); @@ -206,20 +166,11 @@ EventBase::~EventBase() { callback->runLoopCallback(); } - // Delete any unfired callback objects, so that we don't leak memory - // (Note that we don't fire them. The caller is responsible for cleaning up - // its own data structures if it destroys the EventBase with unfired events - // remaining.) - while (!pendingCobTimeouts_.empty()) { - CobTimeout* timeout = &pendingCobTimeouts_.front(); - delete timeout; - } + clearCobTimeouts(); - while (!runBeforeLoopCallbacks_.empty()) { - delete &runBeforeLoopCallbacks_.front(); - } + DCHECK_EQ(0u, runBeforeLoopCallbacks_.size()); - (void) runLoopCallbacks(false); + (void)runLoopCallbacks(); if (!fnRunner_->consumeUntilDrained()) { LOG(ERROR) << "~EventBase(): Unable to drain notification queue"; @@ -231,10 +182,15 @@ EventBase::~EventBase() { std::lock_guard lock(libevent_mutex_); event_base_free(evb_); } + + for (auto storage : localStorageToDtor_) { + storage->onEventBaseDestruction(*this); + } + VLOG(5) << "EventBase(): Destroyed."; } -int EventBase::getNotificationQueueSize() const { +size_t EventBase::getNotificationQueueSize() const { return queue_->size(); } @@ -242,11 +198,29 @@ void EventBase::setMaxReadAtOnce(uint32_t maxAtOnce) { fnRunner_->setMaxReadAtOnce(maxAtOnce); } +void EventBase::checkIsInEventBaseThread() const { + auto evbTid = loopThread_.load(std::memory_order_relaxed); + if (evbTid == std::thread::id()) { + return; + } + + // Using getThreadName(evbTid) instead of name_ will work also if + // the thread name is set outside of EventBase (and name_ is empty). + auto curTid = std::this_thread::get_id(); + CHECK(evbTid == curTid) + << "This logic must be executed in the event base thread. " + << "Event base thread name: \"" + << folly::getThreadName(evbTid).value_or("") + << "\", current thread name: \"" + << folly::getThreadName(curTid).value_or("") << "\""; +} + // Set smoothing coefficient for loop load average; input is # of milliseconds // for exp(-1) decay. -void EventBase::setLoadAvgMsec(uint32_t ms) { - uint64_t us = 1000 * ms; - if (ms > 0) { +void EventBase::setLoadAvgMsec(std::chrono::milliseconds ms) { + assert(enableTimeMeasurement_); + std::chrono::microseconds us = std::chrono::milliseconds(ms); + if (ms > std::chrono::milliseconds::zero()) { maxLatencyLoopTime_.setTimeInterval(us); avgLoopTime_.setTimeInterval(us); } else { @@ -255,6 +229,7 @@ void EventBase::setLoadAvgMsec(uint32_t ms) { } void EventBase::resetLoadAvg(double value) { + assert(enableTimeMeasurement_); avgLoopTime_.reset(value); maxLatencyLoopTime_.reset(value); } @@ -269,7 +244,7 @@ getTimeDelta(std::chrono::steady_clock::time_point* prev) { void EventBase::waitUntilRunning() { while (!isRunning()) { - sched_yield(); + std::this_thread::yield(); } } @@ -284,23 +259,43 @@ bool EventBase::loopOnce(int flags) { bool EventBase::loopBody(int flags) { VLOG(5) << "EventBase(): Starting loop."; + + DCHECK(!invokingLoop_) + << "Your code just tried to loop over an event base from inside another " + << "event base loop. Since libevent is not reentrant, this leads to " + << "undefined behavior in opt builds. Please fix immediately. For the " + << "common case of an inner function that needs to do some synchronous " + << "computation on an event-base, replace getEventBase() by a new, " + << "stack-allocated EvenBase."; + invokingLoop_ = true; + SCOPE_EXIT { + invokingLoop_ = false; + }; + int res = 0; bool ranLoopCallbacks; bool blocking = !(flags & EVLOOP_NONBLOCK); bool once = (flags & EVLOOP_ONCE); - loopThread_.store(pthread_self(), std::memory_order_release); + // time-measurement variables. + std::chrono::steady_clock::time_point prev; + std::chrono::steady_clock::time_point idleStart = {}; + std::chrono::microseconds busy; + std::chrono::microseconds idle; + + loopThread_.store(std::this_thread::get_id(), std::memory_order_release); if (!name_.empty()) { setThreadName(name_); } - auto prev = std::chrono::steady_clock::now(); - int64_t idleStart = std::chrono::duration_cast( - std::chrono::steady_clock::now().time_since_epoch()).count(); + if (enableTimeMeasurement_) { + prev = std::chrono::steady_clock::now(); + idleStart = std::chrono::steady_clock::now(); + } - // TODO: Read stop_ atomically with an acquire barrier. - while (!stop_) { + while (!stop_.load(std::memory_order_acquire)) { + applyLoopKeepAlive(); ++nextLoopCnt_; // Run the before loop callbacks @@ -323,42 +318,49 @@ bool EventBase::loopBody(int flags) { ranLoopCallbacks = runLoopCallbacks(); - int64_t busy = std::chrono::duration_cast( - std::chrono::steady_clock::now().time_since_epoch()).count() - startWork_; - int64_t idle = startWork_ - idleStart; - - avgLoopTime_.addSample(idle, busy); - maxLatencyLoopTime_.addSample(idle, busy); + if (enableTimeMeasurement_) { + busy = std::chrono::duration_cast( + std::chrono::steady_clock::now() - startWork_); + idle = std::chrono::duration_cast( + startWork_ - idleStart); + + avgLoopTime_.addSample(std::chrono::microseconds(idle), + std::chrono::microseconds(busy)); + maxLatencyLoopTime_.addSample(std::chrono::microseconds(idle), + std::chrono::microseconds(busy)); + + if (observer_) { + if (observerSampleCount_++ == observer_->getSampleRate()) { + observerSampleCount_ = 0; + observer_->loopSample(busy.count(), idle.count()); + } + } - if (observer_) { - if (observerSampleCount_++ == observer_->getSampleRate()) { - observerSampleCount_ = 0; - observer_->loopSample(busy, idle); + VLOG(11) << "EventBase " << this << " did not timeout " << + " loop time guess: " << (busy + idle).count() << + " idle time: " << idle.count() << + " busy time: " << busy.count() << + " avgLoopTime: " << avgLoopTime_.get() << + " maxLatencyLoopTime: " << maxLatencyLoopTime_.get() << + " maxLatency_: " << maxLatency_.count() << "us" << + " notificationQueueSize: " << getNotificationQueueSize() << + " nothingHandledYet(): " << nothingHandledYet(); + + // see if our average loop time has exceeded our limit + if ((maxLatency_ > std::chrono::microseconds::zero()) && + (maxLatencyLoopTime_.get() > double(maxLatency_.count()))) { + maxLatencyCob_(); + // back off temporarily -- don't keep spamming maxLatencyCob_ + // if we're only a bit over the limit + maxLatencyLoopTime_.dampen(0.9); } - } - VLOG(11) << "EventBase " << this << " did not timeout " - " loop time guess: " << busy + idle << - " idle time: " << idle << - " busy time: " << busy << - " avgLoopTime: " << avgLoopTime_.get() << - " maxLatencyLoopTime: " << maxLatencyLoopTime_.get() << - " maxLatency_: " << maxLatency_ << - " nothingHandledYet(): "<< nothingHandledYet(); - - // see if our average loop time has exceeded our limit - if ((maxLatency_ > 0) && - (maxLatencyLoopTime_.get() > double(maxLatency_))) { - maxLatencyCob_(); - // back off temporarily -- don't keep spamming maxLatencyCob_ - // if we're only a bit over the limit - maxLatencyLoopTime_.dampen(0.9); + // Our loop run did real work; reset the idle timer + idleStart = std::chrono::steady_clock::now(); + } else { + VLOG(11) << "EventBase " << this << " did not timeout"; } - // Our loop run did real work; reset the idle timer - idleStart = std::chrono::duration_cast( - std::chrono::steady_clock::now().time_since_epoch()).count(); - // If the event loop indicate that there were no more events, and // we also didn't have any loop callbacks to run, there is nothing left to // do. @@ -373,8 +375,10 @@ bool EventBase::loopBody(int flags) { } } - VLOG(5) << "EventBase " << this << " loop time: " << - getTimeDelta(&prev).count(); + if (enableTimeMeasurement_) { + VLOG(11) << "EventBase " << this << " loop time: " << + getTimeDelta(&prev).count(); + } if (once) { break; @@ -393,44 +397,80 @@ bool EventBase::loopBody(int flags) { return false; } - loopThread_.store(0, std::memory_order_release); + loopThread_.store({}, std::memory_order_release); VLOG(5) << "EventBase(): Done with loop."; return true; } -void EventBase::loopForever() { - // Update the notification queue event to treat it as a normal (non-internal) - // event. The notification queue event always remains installed, and the main - // loop won't exit with it installed. - fnRunner_->stopConsuming(); - fnRunner_->startConsuming(this, queue_.get()); +ssize_t EventBase::loopKeepAliveCount() { + if (loopKeepAliveCountAtomic_.load(std::memory_order_relaxed)) { + loopKeepAliveCount_ += + loopKeepAliveCountAtomic_.exchange(0, std::memory_order_relaxed); + } + DCHECK_GE(loopKeepAliveCount_, 0); - bool ret = loop(); + return loopKeepAliveCount_; +} - // Restore the notification queue internal flag - fnRunner_->stopConsuming(); - fnRunner_->startConsumingInternal(this, queue_.get()); +void EventBase::applyLoopKeepAlive() { + auto keepAliveCount = loopKeepAliveCount(); + // Make sure default VirtualEventBase won't hold EventBase::loop() forever. + if (virtualEventBase_ && virtualEventBase_->keepAliveCount() == 1) { + --keepAliveCount; + } + + if (loopKeepAliveActive_ && keepAliveCount == 0) { + // Restore the notification queue internal flag + fnRunner_->stopConsuming(); + fnRunner_->startConsumingInternal(this, queue_.get()); + loopKeepAliveActive_ = false; + } else if (!loopKeepAliveActive_ && keepAliveCount > 0) { + // Update the notification queue event to treat it as a normal + // (non-internal) event. The notification queue event always remains + // installed, and the main loop won't exit with it installed. + fnRunner_->stopConsuming(); + fnRunner_->startConsuming(this, queue_.get()); + loopKeepAliveActive_ = true; + } +} + +void EventBase::loopForever() { + bool ret; + { + SCOPE_EXIT { + applyLoopKeepAlive(); + }; + // Make sure notification queue events are treated as normal events. + // We can't use loopKeepAlive() here since LoopKeepAlive token can only be + // released inside a loop. + ++loopKeepAliveCount_; + SCOPE_EXIT { + --loopKeepAliveCount_; + }; + ret = loop(); + } if (!ret) { folly::throwSystemError("error in EventBase::loopForever()"); } } -bool EventBase::bumpHandlingTime() { +void EventBase::bumpHandlingTime() { + if (!enableTimeMeasurement_) { + return; + } + VLOG(11) << "EventBase " << this << " " << __PRETTY_FUNCTION__ << " (loop) latest " << latestLoopCnt_ << " next " << nextLoopCnt_; - if(nothingHandledYet()) { + if (nothingHandledYet()) { latestLoopCnt_ = nextLoopCnt_; // set the time - startWork_ = std::chrono::duration_cast( - std::chrono::steady_clock::now().time_since_epoch()).count(); + startWork_ = std::chrono::steady_clock::now(); - VLOG(11) << "EventBase " << this << " " << __PRETTY_FUNCTION__ << - " (loop) startWork_ " << startWork_; - return true; + VLOG(11) << "EventBase " << this << " " << __PRETTY_FUNCTION__ + << " (loop) startWork_ " << startWork_.time_since_epoch().count(); } - return false; } void EventBase::terminateLoopSoon() { @@ -455,7 +495,7 @@ void EventBase::terminateLoopSoon() { // this likely means the EventBase already has lots of events waiting // anyway. try { - queue_->putMessage(std::make_pair(nullptr, nullptr)); + queue_->putMessage(nullptr); } catch (...) { // We don't care if putMessage() fails. This likely means // the EventBase already has lots of events waiting anyway. @@ -463,7 +503,7 @@ void EventBase::terminateLoopSoon() { } void EventBase::runInLoop(LoopCallback* callback, bool thisIteration) { - DCHECK(isInEventBaseThread()); + dcheckIsInEventBaseThread(); callback->cancelLoopCallback(); callback->context_ = RequestContext::saveContext(); if (runOnceCallbacks_ != nullptr && thisIteration) { @@ -473,20 +513,9 @@ void EventBase::runInLoop(LoopCallback* callback, bool thisIteration) { } } -void EventBase::runInLoop(const Cob& cob, bool thisIteration) { - DCHECK(isInEventBaseThread()); - auto wrapper = new FunctionLoopCallback(cob); - wrapper->context_ = RequestContext::saveContext(); - if (runOnceCallbacks_ != nullptr && thisIteration) { - runOnceCallbacks_->push_back(*wrapper); - } else { - loopCallbacks_.push_back(*wrapper); - } -} - -void EventBase::runInLoop(Cob&& cob, bool thisIteration) { - DCHECK(isInEventBaseThread()); - auto wrapper = new FunctionLoopCallback(std::move(cob)); +void EventBase::runInLoop(Func cob, bool thisIteration) { + dcheckIsInEventBaseThread(); + auto wrapper = new FunctionLoopCallback(std::move(cob)); wrapper->context_ = RequestContext::saveContext(); if (runOnceCallbacks_ != nullptr && thisIteration) { runOnceCallbacks_->push_back(*wrapper); @@ -496,18 +525,18 @@ void EventBase::runInLoop(Cob&& cob, bool thisIteration) { } void EventBase::runOnDestruction(LoopCallback* callback) { - DCHECK(isInEventBaseThread()); + std::lock_guard lg(onDestructionCallbacksMutex_); callback->cancelLoopCallback(); onDestructionCallbacks_.push_back(*callback); } void EventBase::runBeforeLoop(LoopCallback* callback) { - DCHECK(isInEventBaseThread()); + dcheckIsInEventBaseThread(); callback->cancelLoopCallback(); runBeforeLoopCallbacks_.push_back(*callback); } -bool EventBase::runInEventBaseThread(void (*fn)(void*), void* arg) { +bool EventBase::runInEventBaseThread(Func fn) { // Send the message. // It will be received by the FunctionRunner in the EventBase's thread. @@ -520,62 +549,52 @@ bool EventBase::runInEventBaseThread(void (*fn)(void*), void* arg) { // Short-circuit if we are already in our event base if (inRunningEventBaseThread()) { - runInLoop(new RunInLoopCallback(fn, arg)); + runInLoop(std::move(fn)); return true; - } try { - queue_->putMessage(std::make_pair(fn, arg)); + queue_->putMessage(std::move(fn)); } catch (const std::exception& ex) { LOG(ERROR) << "EventBase " << this << ": failed to schedule function " - << fn << "for EventBase thread: " << ex.what(); + << "for EventBase thread: " << ex.what(); return false; } return true; } -bool EventBase::runInEventBaseThread(const Cob& fn) { - // Short-circuit if we are already in our event base +bool EventBase::runInEventBaseThreadAndWait(Func fn) { if (inRunningEventBaseThread()) { - runInLoop(fn); - return true; - } - - Cob* fnCopy; - // Allocate a copy of the function so we can pass it to the other thread - // The other thread will delete this copy once the function has been run - try { - fnCopy = new Cob(fn); - } catch (const std::bad_alloc& ex) { - LOG(ERROR) << "failed to allocate tr::function copy " - << "for runInEventBaseThread()"; + LOG(ERROR) << "EventBase " << this << ": Waiting in the event loop is not " + << "allowed"; return false; } - if (!runInEventBaseThread(&EventBase::runFunctionPtr, fnCopy)) { - delete fnCopy; - return false; - } + Baton<> ready; + runInEventBaseThread([&ready, fn = std::move(fn)]() mutable { + SCOPE_EXIT { + ready.post(); + }; + // A trick to force the stored functor to be executed and then destructed + // before posting the baton and waking the waiting thread. + copy(std::move(fn))(); + }); + ready.wait(); return true; } -bool EventBase::runAfterDelay(const Cob& cob, - int milliseconds, - TimeoutManager::InternalEnum in) { - CobTimeout* timeout = new CobTimeout(this, cob, in); - if (!timeout->scheduleTimeout(milliseconds)) { - delete timeout; - return false; +bool EventBase::runImmediatelyOrRunInEventBaseThreadAndWait(Func fn) { + if (isInEventBaseThread()) { + fn(); + return true; + } else { + return runInEventBaseThreadAndWait(std::move(fn)); } - - pendingCobTimeouts_.push_back(*timeout); - return true; } -bool EventBase::runLoopCallbacks(bool setContext) { +bool EventBase::runLoopCallbacks() { if (!loopCallbacks_.empty()) { bumpHandlingTime(); // Swap the loopCallbacks_ list with a temporary list on our stack. @@ -593,9 +612,7 @@ bool EventBase::runLoopCallbacks(bool setContext) { while (!currentCallbacks.empty()) { LoopCallback* callback = ¤tCallbacks.front(); currentCallbacks.pop_front(); - if (setContext) { - RequestContext::setContext(callback->context_); - } + folly::RequestContextScopeGuard rctx(std::move(callback->context_)); callback->runLoopCallback(); } @@ -607,12 +624,12 @@ bool EventBase::runLoopCallbacks(bool setContext) { void EventBase::initNotificationQueue() { // Infinite size queue - queue_.reset(new NotificationQueue>()); + queue_ = std::make_unique>(); // We allocate fnRunner_ separately, rather than declaring it directly // as a member of EventBase solely so that we don't need to include // NotificationQueue.h from EventBase.h - fnRunner_.reset(new FunctionRunner()); + fnRunner_ = std::make_unique(); // Mark this as an internal event, so event_base_loop() will return if // there are no other events besides this one installed. @@ -626,8 +643,9 @@ void EventBase::initNotificationQueue() { fnRunner_->startConsumingInternal(this, queue_.get()); } -void EventBase::SmoothLoopTime::setTimeInterval(uint64_t timeInterval) { - expCoeff_ = -1.0/timeInterval; +void EventBase::SmoothLoopTime::setTimeInterval( + std::chrono::microseconds timeInterval) { + expCoeff_ = -1.0 / timeInterval.count(); VLOG(11) << "expCoeff_ " << expCoeff_ << " " << __PRETTY_FUNCTION__; } @@ -635,65 +653,39 @@ void EventBase::SmoothLoopTime::reset(double value) { value_ = value; } -void EventBase::SmoothLoopTime::addSample(int64_t idle, int64_t busy) { - /* - * Position at which the busy sample is considered to be taken. - * (Allows to quickly skew our average without editing much code) - */ - enum BusySamplePosition { - RIGHT = 0, // busy sample placed at the end of the iteration - CENTER = 1, // busy sample placed at the middle point of the iteration - LEFT = 2, // busy sample placed at the beginning of the iteration - }; - - VLOG(11) << "idle " << idle << " oldBusyLeftover_ " << oldBusyLeftover_ << - " idle + oldBusyLeftover_ " << idle + oldBusyLeftover_ << - " busy " << busy << " " << __PRETTY_FUNCTION__; +void EventBase::SmoothLoopTime::addSample( + std::chrono::microseconds idle, + std::chrono::microseconds busy) { + /* + * Position at which the busy sample is considered to be taken. + * (Allows to quickly skew our average without editing much code) + */ + enum BusySamplePosition { + RIGHT = 0, // busy sample placed at the end of the iteration + CENTER = 1, // busy sample placed at the middle point of the iteration + LEFT = 2, // busy sample placed at the beginning of the iteration + }; + + // See http://en.wikipedia.org/wiki/Moving_average#Exponential_moving_average + // and D676020 for more info on this calculation. + VLOG(11) << "idle " << idle.count() << " oldBusyLeftover_ " + << oldBusyLeftover_.count() << " idle + oldBusyLeftover_ " + << (idle + oldBusyLeftover_).count() << " busy " << busy.count() + << " " << __PRETTY_FUNCTION__; idle += oldBusyLeftover_ + busy; oldBusyLeftover_ = (busy * BusySamplePosition::CENTER) / 2; idle -= oldBusyLeftover_; - double coeff = exp(idle * expCoeff_); + double coeff = exp(idle.count() * expCoeff_); value_ *= coeff; - value_ += (1.0 - coeff) * busy; + value_ += (1.0 - coeff) * busy.count(); } -bool EventBase::nothingHandledYet() { +bool EventBase::nothingHandledYet() const noexcept { VLOG(11) << "latest " << latestLoopCnt_ << " next " << nextLoopCnt_; return (nextLoopCnt_ != latestLoopCnt_); } -/* static */ -void EventBase::runFunctionPtr(Cob* fn) { - // The function should never throw an exception, because we have no - // way of knowing what sort of error handling to perform. - // - // If it does throw, log a message and abort the program. - try { - (*fn)(); - } catch (const std::exception &ex) { - LOG(ERROR) << "runInEventBaseThread() std::function threw a " - << typeid(ex).name() << " exception: " << ex.what(); - abort(); - } catch (...) { - LOG(ERROR) << "runInEventBaseThread() std::function threw an exception"; - abort(); - } - - // The function object was allocated by runInEventBaseThread(). - // Delete it once it has been run. - delete fn; -} - -EventBase::RunInLoopCallback::RunInLoopCallback(void (*fn)(void*), void* arg) - : fn_(fn) - , arg_(arg) {} - -void EventBase::RunInLoopCallback::runLoopCallback() noexcept { - fn_(arg_); - delete this; -} - void EventBase::attachTimeoutManager(AsyncTimeout* obj, InternalEnum internal) { @@ -703,7 +695,7 @@ void EventBase::attachTimeoutManager(AsyncTimeout* obj, event_base_set(getLibeventBase(), ev); if (internal == AsyncTimeout::InternalEnum::INTERNAL) { // Set the EVLIST_INTERNAL flag - ev->ev_flags |= EVLIST_INTERNAL; + event_ref_flags(ev) |= EVLIST_INTERNAL; } } @@ -714,12 +706,12 @@ void EventBase::detachTimeoutManager(AsyncTimeout* obj) { } bool EventBase::scheduleTimeout(AsyncTimeout* obj, - std::chrono::milliseconds timeout) { - assert(isInEventBaseThread()); + TimeoutManager::timeout_type timeout) { + dcheckIsInEventBaseThread(); // Set up the timeval and add the event struct timeval tv; - tv.tv_sec = timeout.count() / 1000LL; - tv.tv_usec = (timeout.count() % 1000LL) * 1000LL; + tv.tv_sec = long(timeout.count() / 1000LL); + tv.tv_usec = long((timeout.count() % 1000LL) * 1000LL); struct event* ev = obj->getEvent(); if (event_add(ev, &tv) < 0) { @@ -731,7 +723,7 @@ bool EventBase::scheduleTimeout(AsyncTimeout* obj, } void EventBase::cancelTimeout(AsyncTimeout* obj) { - assert(isInEventBaseThread()); + dcheckIsInEventBaseThread(); struct event* ev = obj->getEvent(); if (EventUtil::isEventRegistered(ev)) { event_del(ev); @@ -739,7 +731,7 @@ void EventBase::cancelTimeout(AsyncTimeout* obj) { } void EventBase::setName(const std::string& name) { - assert(isInEventBaseThread()); + dcheckIsInEventBaseThread(); name_ = name; if (isRunning()) { @@ -749,11 +741,19 @@ void EventBase::setName(const std::string& name) { } const std::string& EventBase::getName() { - assert(isInEventBaseThread()); + dcheckIsInEventBaseThread(); return name_; } const char* EventBase::getLibeventVersion() { return event_get_version(); } const char* EventBase::getLibeventMethod() { return event_get_method(); } -} // folly +VirtualEventBase& EventBase::getVirtualEventBase() { + folly::call_once(virtualEventBaseInitFlag_, [&] { + virtualEventBase_ = std::make_unique(*this); + }); + + return *virtualEventBase_; +} + +} // namespace folly