From 36d22d82aa202bb199967e9512281e9a53db42c9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 21:33:14 +0200 Subject: Adding upstream version 115.7.0esr. Signed-off-by: Daniel Baumann --- xpcom/tests/gtest/TestThrottledEventQueue.cpp | 613 ++++++++++++++++++++++++++ 1 file changed, 613 insertions(+) create mode 100644 xpcom/tests/gtest/TestThrottledEventQueue.cpp (limited to 'xpcom/tests/gtest/TestThrottledEventQueue.cpp') diff --git a/xpcom/tests/gtest/TestThrottledEventQueue.cpp b/xpcom/tests/gtest/TestThrottledEventQueue.cpp new file mode 100644 index 0000000000..64f34ff14f --- /dev/null +++ b/xpcom/tests/gtest/TestThrottledEventQueue.cpp @@ -0,0 +1,613 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include +#include +#include +#include + +#include "MainThreadUtils.h" +#include "gtest/gtest.h" +#include "mozilla/Attributes.h" +#include "mozilla/CondVar.h" +#include "mozilla/gtest/MozAssertions.h" +#include "mozilla/Mutex.h" +#include "mozilla/RefPtr.h" +#include "mozilla/ThrottledEventQueue.h" +#include "nsCOMPtr.h" +#include "nsError.h" +#include "nsIRunnable.h" +#include "nsISerialEventTarget.h" +#include "nsIThread.h" +#include "nsThreadUtils.h" +#include "prinrval.h" + +using mozilla::CondVar; +using mozilla::MakeRefPtr; +using mozilla::Mutex; +using mozilla::MutexAutoLock; +using mozilla::ThrottledEventQueue; +using std::function; +using std::string; + +namespace TestThrottledEventQueue { + +// A simple queue of runnables, to serve as the base target of +// ThrottledEventQueues in tests. +// +// This is much simpler than mozilla::TaskQueue, and so better for unit tests. +// It's about the same as mozilla::EventQueue, but that doesn't implement +// nsIEventTarget, so it can't be the base target of a ThrottledEventQueue. +struct RunnableQueue : nsISerialEventTarget { + std::queue> runnables; + + bool IsEmpty() { return runnables.empty(); } + size_t Length() { return runnables.size(); } + + [[nodiscard]] nsresult Run() { + while (!runnables.empty()) { + auto runnable = std::move(runnables.front()); + runnables.pop(); + nsresult rv = runnable->Run(); + if (NS_FAILED(rv)) return rv; + } + + return NS_OK; + } + + // nsIEventTarget methods + + [[nodiscard]] NS_IMETHODIMP Dispatch(already_AddRefed aRunnable, + uint32_t aFlags) override { + MOZ_ALWAYS_TRUE(aFlags == nsIEventTarget::DISPATCH_NORMAL); + runnables.push(aRunnable); + return NS_OK; + } + + [[nodiscard]] NS_IMETHODIMP DispatchFromScript(nsIRunnable* aRunnable, + uint32_t aFlags) override { + RefPtr r = aRunnable; + return Dispatch(r.forget(), aFlags); + } + + NS_IMETHOD_(bool) + IsOnCurrentThreadInfallible(void) override { return NS_IsMainThread(); } + + [[nodiscard]] NS_IMETHOD IsOnCurrentThread(bool* retval) override { + *retval = IsOnCurrentThreadInfallible(); + return NS_OK; + } + + [[nodiscard]] NS_IMETHODIMP DelayedDispatch( + already_AddRefed aEvent, uint32_t aDelay) override { + return NS_ERROR_NOT_IMPLEMENTED; + } + + NS_IMETHOD RegisterShutdownTask(nsITargetShutdownTask*) override { + return NS_ERROR_NOT_IMPLEMENTED; + } + + NS_IMETHOD UnregisterShutdownTask(nsITargetShutdownTask*) override { + return NS_ERROR_NOT_IMPLEMENTED; + } + + // nsISupports methods + + NS_DECL_THREADSAFE_ISUPPORTS + + private: + virtual ~RunnableQueue() = default; +}; + +NS_IMPL_ISUPPORTS(RunnableQueue, nsIEventTarget, nsISerialEventTarget) + +static void Enqueue(nsIEventTarget* target, function&& aCallable) { + nsresult rv = target->Dispatch( + NS_NewRunnableFunction("TEQ GTest", std::move(aCallable))); + MOZ_ALWAYS_TRUE(NS_SUCCEEDED(rv)); +} + +} // namespace TestThrottledEventQueue + +using namespace TestThrottledEventQueue; + +TEST(ThrottledEventQueue, RunnableQueue) +{ + string log; + + RefPtr queue = MakeRefPtr(); + Enqueue(queue, [&]() { log += 'a'; }); + Enqueue(queue, [&]() { log += 'b'; }); + Enqueue(queue, [&]() { log += 'c'; }); + + ASSERT_EQ(log, ""); + ASSERT_NS_SUCCEEDED(queue->Run()); + ASSERT_EQ(log, "abc"); +} + +TEST(ThrottledEventQueue, SimpleDispatch) +{ + string log; + + auto base = MakeRefPtr(); + RefPtr throttled = + ThrottledEventQueue::Create(base, "test queue 1"); + + Enqueue(throttled, [&]() { log += 'a'; }); + ASSERT_NS_SUCCEEDED(base->Run()); + ASSERT_EQ(log, "a"); + + ASSERT_TRUE(base->IsEmpty()); + ASSERT_TRUE(throttled->IsEmpty()); +} + +TEST(ThrottledEventQueue, MixedDispatch) +{ + string log; + + auto base = MakeRefPtr(); + RefPtr throttled = + ThrottledEventQueue::Create(base, "test queue 2"); + + // A ThrottledEventQueue limits its impact on the base target by only queuing + // its next event on the base once the prior event has been run. What it + // actually queues on the base is a sort of proxy event called an + // "executor": the base running the executor draws an event from the + // ThrottledEventQueue and runs that. If the ThrottledEventQueue has further + // events, it re-queues the executor on the base, effectively "going to the + // back of the line". + + // Queue an event on the ThrottledEventQueue. This also queues the "executor" + // event on the base. + Enqueue(throttled, [&]() { log += 'a'; }); + ASSERT_EQ(throttled->Length(), 1U); + ASSERT_EQ(base->Length(), 1U); + + // Add a second event to the throttled queue. The executor is already queued. + Enqueue(throttled, [&]() { log += 'b'; }); + ASSERT_EQ(throttled->Length(), 2U); + ASSERT_EQ(base->Length(), 1U); + + // Add an event directly to the base, after the executor. + Enqueue(base, [&]() { log += 'c'; }); + ASSERT_EQ(throttled->Length(), 2U); + ASSERT_EQ(base->Length(), 2U); + + // Run the base target. This runs: + // - the executor, which runs the first event from the ThrottledEventQueue, + // and re-enqueues itself + // - the event queued directly on the base + // - the executor again, which runs the second event from the + // ThrottledEventQueue. + ASSERT_EQ(log, ""); + ASSERT_NS_SUCCEEDED(base->Run()); + ASSERT_EQ(log, "acb"); + + ASSERT_TRUE(base->IsEmpty()); + ASSERT_TRUE(throttled->IsEmpty()); +} + +TEST(ThrottledEventQueue, EnqueueFromRun) +{ + string log; + + auto base = MakeRefPtr(); + RefPtr throttled = + ThrottledEventQueue::Create(base, "test queue 3"); + + // When an event from the throttled queue dispatches a new event directly to + // the base target, it is queued after the executor, so the next event from + // the throttled queue will run before it. + Enqueue(base, [&]() { log += 'a'; }); + Enqueue(throttled, [&]() { + log += 'b'; + Enqueue(base, [&]() { log += 'c'; }); + }); + Enqueue(throttled, [&]() { log += 'd'; }); + + ASSERT_EQ(log, ""); + ASSERT_NS_SUCCEEDED(base->Run()); + ASSERT_EQ(log, "abdc"); + + ASSERT_TRUE(base->IsEmpty()); + ASSERT_TRUE(throttled->IsEmpty()); +} + +TEST(ThrottledEventQueue, RunFromRun) +{ + string log; + + auto base = MakeRefPtr(); + RefPtr throttled = + ThrottledEventQueue::Create(base, "test queue 4"); + + // Running the event queue from within an event (i.e., a nested event loop) + // does not stall the ThrottledEventQueue. + Enqueue(throttled, [&]() { + log += '('; + // This should run subsequent events from throttled. + ASSERT_NS_SUCCEEDED(base->Run()); + log += ')'; + }); + + Enqueue(throttled, [&]() { log += 'a'; }); + + ASSERT_EQ(log, ""); + ASSERT_NS_SUCCEEDED(base->Run()); + ASSERT_EQ(log, "(a)"); + + ASSERT_TRUE(base->IsEmpty()); + ASSERT_TRUE(throttled->IsEmpty()); +} + +TEST(ThrottledEventQueue, DropWhileRunning) +{ + string log; + + auto base = MakeRefPtr(); + + // If we drop the event queue while it still has events, they still run. + { + RefPtr throttled = + ThrottledEventQueue::Create(base, "test queue 5"); + Enqueue(throttled, [&]() { log += 'a'; }); + } + + ASSERT_EQ(log, ""); + ASSERT_NS_SUCCEEDED(base->Run()); + ASSERT_EQ(log, "a"); +} + +TEST(ThrottledEventQueue, AwaitIdle) +{ + Mutex mutex MOZ_UNANNOTATED("TEQ AwaitIdle"); + CondVar cond(mutex, "TEQ AwaitIdle"); + + string dequeue_await; // mutex + bool threadFinished = false; // mutex & cond + bool runnableFinished = false; // main thread only + + auto base = MakeRefPtr(); + RefPtr throttled = + ThrottledEventQueue::Create(base, "test queue 6"); + + // Put an event in the queue so the AwaitIdle might block. + Enqueue(throttled, [&]() { runnableFinished = true; }); + + // Create a separate thread that waits for the queue to become idle, and + // then takes observable action. + nsCOMPtr await = NS_NewRunnableFunction("TEQ AwaitIdle", [&]() { + throttled->AwaitIdle(); + MutexAutoLock lock(mutex); + dequeue_await += " await"; + threadFinished = true; + cond.Notify(); + }); + + nsCOMPtr thread; + nsresult rv = + NS_NewNamedThread("TEQ AwaitIdle", getter_AddRefs(thread), await); + ASSERT_NS_SUCCEEDED(rv); + + // We can't guarantee that the thread has reached the AwaitIdle call, but we + // can get pretty close. Either way, it shouldn't affect the behavior of the + // test. + PR_Sleep(PR_MillisecondsToInterval(100)); + + // Drain the queue. + { + MutexAutoLock lock(mutex); + ASSERT_EQ(dequeue_await, ""); + dequeue_await += "dequeue"; + ASSERT_FALSE(threadFinished); + } + ASSERT_FALSE(runnableFinished); + ASSERT_NS_SUCCEEDED(base->Run()); + ASSERT_TRUE(runnableFinished); + + // Wait for the thread to finish. + { + MutexAutoLock lock(mutex); + while (!threadFinished) cond.Wait(); + ASSERT_EQ(dequeue_await, "dequeue await"); + } + + ASSERT_NS_SUCCEEDED(thread->Shutdown()); +} + +TEST(ThrottledEventQueue, AwaitIdleMixed) +{ + // Create a separate thread that waits for the queue to become idle, and + // then takes observable action. + nsCOMPtr thread; + ASSERT_TRUE(NS_SUCCEEDED( + NS_NewNamedThread("AwaitIdleMixed", getter_AddRefs(thread)))); + + Mutex mutex MOZ_UNANNOTATED("AwaitIdleMixed"); + CondVar cond(mutex, "AwaitIdleMixed"); + + // The following are protected by mutex and cond, above. + string log; + bool threadStarted = false; + bool threadFinished = false; + + auto base = MakeRefPtr(); + RefPtr throttled = + ThrottledEventQueue::Create(base, "test queue 7"); + + Enqueue(throttled, [&]() { + MutexAutoLock lock(mutex); + log += 'a'; + }); + + Enqueue(throttled, [&]() { + MutexAutoLock lock(mutex); + log += 'b'; + }); + + nsCOMPtr await = NS_NewRunnableFunction("AwaitIdleMixed", [&]() { + { + MutexAutoLock lock(mutex); + + // Note that we are about to begin awaiting. When the main thread sees + // this notification, it will begin draining the queue. + log += '('; + threadStarted = true; + cond.Notify(); + } + + // Wait for the main thread to drain the TEQ. + throttled->AwaitIdle(); + + { + MutexAutoLock lock(mutex); + + // Note that we have finished awaiting. + log += ')'; + threadFinished = true; + cond.Notify(); + } + }); + + { + MutexAutoLock lock(mutex); + ASSERT_EQ(log, ""); + } + + ASSERT_NS_SUCCEEDED(thread->Dispatch(await.forget())); + + // Wait for the thread to be ready to await. We can't be sure it will actually + // be blocking before we get around to draining the event queue, but that's + // the nature of the API; this test should work even if we drain the queue + // before it awaits. + { + MutexAutoLock lock(mutex); + while (!threadStarted) cond.Wait(); + ASSERT_EQ(log, "("); + } + + // Let the queue drain. + ASSERT_NS_SUCCEEDED(base->Run()); + + { + MutexAutoLock lock(mutex); + // The first runnable must always finish before AwaitIdle returns. But the + // TEQ notifies the condition variable as soon as it dequeues the last + // runnable, without waiting for that runnable to complete. So the thread + // and the last runnable could run in either order. Or, we might beat the + // thread to the mutex. + // + // (The only combination excluded here is "(a)": the 'b' runnable should + // definitely have run.) + ASSERT_TRUE(log == "(ab" || log == "(a)b" || log == "(ab)"); + while (!threadFinished) cond.Wait(); + ASSERT_TRUE(log == "(a)b" || log == "(ab)"); + } + + ASSERT_NS_SUCCEEDED(thread->Shutdown()); +} + +TEST(ThrottledEventQueue, SimplePauseResume) +{ + string log; + + auto base = MakeRefPtr(); + RefPtr throttled = + ThrottledEventQueue::Create(base, "test queue 8"); + + ASSERT_FALSE(throttled->IsPaused()); + + Enqueue(throttled, [&]() { log += 'a'; }); + + ASSERT_EQ(log, ""); + ASSERT_NS_SUCCEEDED(base->Run()); + ASSERT_EQ(log, "a"); + + ASSERT_NS_SUCCEEDED(throttled->SetIsPaused(true)); + ASSERT_TRUE(throttled->IsPaused()); + + Enqueue(throttled, [&]() { log += 'b'; }); + + ASSERT_EQ(log, "a"); + ASSERT_NS_SUCCEEDED(base->Run()); + ASSERT_EQ(log, "a"); + + ASSERT_NS_SUCCEEDED(throttled->SetIsPaused(false)); + ASSERT_FALSE(throttled->IsPaused()); + + ASSERT_EQ(log, "a"); + ASSERT_NS_SUCCEEDED(base->Run()); + ASSERT_EQ(log, "ab"); + + ASSERT_TRUE(base->IsEmpty()); + ASSERT_TRUE(throttled->IsEmpty()); +} + +TEST(ThrottledEventQueue, MixedPauseResume) +{ + string log; + + auto base = MakeRefPtr(); + RefPtr throttled = + ThrottledEventQueue::Create(base, "test queue 9"); + + ASSERT_FALSE(throttled->IsPaused()); + + Enqueue(base, [&]() { log += 'A'; }); + Enqueue(throttled, [&]() { + log += 'b'; + MOZ_ALWAYS_TRUE(NS_SUCCEEDED(throttled->SetIsPaused(true))); + }); + Enqueue(throttled, [&]() { log += 'c'; }); + Enqueue(base, [&]() { log += 'D'; }); + + ASSERT_EQ(log, ""); + ASSERT_NS_SUCCEEDED(base->Run()); + // Since the 'b' event paused the throttled queue, 'c' should not have run. + // but 'D' was enqueued directly on the base, and should have run. + ASSERT_EQ(log, "AbD"); + ASSERT_TRUE(base->IsEmpty()); + ASSERT_FALSE(throttled->IsEmpty()); + ASSERT_TRUE(throttled->IsPaused()); + + Enqueue(base, [&]() { log += 'E'; }); + ASSERT_NS_SUCCEEDED(throttled->SetIsPaused(false)); + Enqueue(base, [&]() { log += 'F'; }); + ASSERT_FALSE(throttled->IsPaused()); + + ASSERT_NS_SUCCEEDED(base->Run()); + // Since we've unpaused, 'c' should be able to run now. The executor should + // have been enqueued between 'E' and 'F'. + ASSERT_EQ(log, "AbDEcF"); + + ASSERT_TRUE(base->IsEmpty()); + ASSERT_TRUE(throttled->IsEmpty()); +} + +TEST(ThrottledEventQueue, AwaitIdlePaused) +{ + Mutex mutex MOZ_UNANNOTATED("AwaitIdlePaused"); + CondVar cond(mutex, "AwaitIdlePaused"); + + string dequeue_await; // mutex + bool threadFinished = false; // mutex & cond + bool runnableFinished = false; // main thread only + + auto base = MakeRefPtr(); + RefPtr throttled = + ThrottledEventQueue::Create(base, "test queue 10"); + + ASSERT_NS_SUCCEEDED(throttled->SetIsPaused(true)); + + // Put an event in the queue so the AwaitIdle might block. Since throttled is + // paused, this should not enqueue an executor in the base target. + Enqueue(throttled, [&]() { runnableFinished = true; }); + ASSERT_TRUE(base->IsEmpty()); + + // Create a separate thread that waits for the queue to become idle, and + // then takes observable action. + nsCOMPtr await = + NS_NewRunnableFunction("AwaitIdlePaused", [&]() { + throttled->AwaitIdle(); + MutexAutoLock lock(mutex); + dequeue_await += " await"; + threadFinished = true; + cond.Notify(); + }); + + nsCOMPtr thread; + nsresult rv = + NS_NewNamedThread("AwaitIdlePaused", getter_AddRefs(thread), await); + ASSERT_NS_SUCCEEDED(rv); + + // We can't guarantee that the thread has reached the AwaitIdle call, but we + // can get pretty close. Either way, it shouldn't affect the behavior of the + // test. + PR_Sleep(PR_MillisecondsToInterval(100)); + + // The AwaitIdle call should be blocked, even though there is no executor, + // because throttled is paused. + { + MutexAutoLock lock(mutex); + ASSERT_EQ(dequeue_await, ""); + dequeue_await += "dequeue"; + ASSERT_FALSE(threadFinished); + } + + // A paused TEQ contributes no events to its base target. (This is covered by + // other tests...) + ASSERT_NS_SUCCEEDED(base->Run()); + ASSERT_TRUE(base->IsEmpty()); + ASSERT_FALSE(throttled->IsEmpty()); + + // Resume and drain the queue. + ASSERT_FALSE(runnableFinished); + ASSERT_NS_SUCCEEDED(throttled->SetIsPaused(false)); + ASSERT_NS_SUCCEEDED(base->Run()); + ASSERT_TRUE(base->IsEmpty()); + ASSERT_TRUE(throttled->IsEmpty()); + ASSERT_TRUE(runnableFinished); + + // Wait for the thread to finish. + { + MutexAutoLock lock(mutex); + while (!threadFinished) cond.Wait(); + ASSERT_EQ(dequeue_await, "dequeue await"); + } + + ASSERT_NS_SUCCEEDED(thread->Shutdown()); +} + +TEST(ThrottledEventQueue, ExecutorTransitions) +{ + string log; + + auto base = MakeRefPtr(); + RefPtr throttled = + ThrottledEventQueue::Create(base, "test queue 11"); + + ASSERT_NS_SUCCEEDED(throttled->SetIsPaused(true)); + + // Since we're paused, queueing an event on throttled shouldn't queue the + // executor on the base target. + Enqueue(throttled, [&]() { log += 'a'; }); + ASSERT_EQ(throttled->Length(), 1U); + ASSERT_EQ(base->Length(), 0U); + + // Resuming throttled should create the executor, since throttled is not + // empty. + ASSERT_NS_SUCCEEDED(throttled->SetIsPaused(false)); + ASSERT_EQ(throttled->Length(), 1U); + ASSERT_EQ(base->Length(), 1U); + + // Pausing can't remove the executor from the base target since we've already + // queued it there, but it can ensure that it doesn't do anything. + ASSERT_NS_SUCCEEDED(throttled->SetIsPaused(true)); + + ASSERT_EQ(log, ""); + ASSERT_NS_SUCCEEDED(base->Run()); + ASSERT_EQ(log, ""); + ASSERT_EQ(throttled->Length(), 1U); + ASSERT_EQ(base->Length(), 0U); + + // As before, resuming must create the executor, since throttled is not empty. + ASSERT_NS_SUCCEEDED(throttled->SetIsPaused(false)); + ASSERT_EQ(throttled->Length(), 1U); + ASSERT_EQ(base->Length(), 1U); + + ASSERT_EQ(log, ""); + ASSERT_NS_SUCCEEDED(base->Run()); + ASSERT_EQ(log, "a"); + ASSERT_EQ(throttled->Length(), 0U); + ASSERT_EQ(base->Length(), 0U); + + // Since throttled is empty, pausing and resuming now should not enqueue an + // executor. + ASSERT_NS_SUCCEEDED(throttled->SetIsPaused(true)); + ASSERT_NS_SUCCEEDED(throttled->SetIsPaused(false)); + ASSERT_EQ(throttled->Length(), 0U); + ASSERT_EQ(base->Length(), 0U); +} -- cgit v1.2.3