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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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
#include "gtest/gtest.h"
#include "mozilla/dom/CCGCScheduler.h"
#include "mozilla/TimeStamp.h"
// This is a test for mozilla::CCGCScheduler.
using namespace mozilla;
MOZ_RUNINIT static TimeDuration kOneSecond = TimeDuration::FromSeconds(1);
MOZ_RUNINIT static TimeDuration kTenthSecond = TimeDuration::FromSeconds(0.1);
MOZ_RUNINIT static TimeDuration kFrameDuration =
TimeDuration::FromSeconds(1.0 / 60.0);
MOZ_RUNINIT static mozilla::TimeStamp sNow = TimeStamp::Now();
static mozilla::TimeStamp AdvanceTime(TimeDuration aDuration) {
sNow += aDuration;
return sNow;
}
static TimeStamp Now() { return sNow; }
static uint32_t sSuspected = 0;
static uint32_t SuspectedCCObjects() { return sSuspected; }
static void SetNumSuspected(uint32_t n) { sSuspected = n; }
static void SuspectMore(uint32_t n) { sSuspected += n; }
using CCRunnerState = mozilla::CCGCScheduler::CCRunnerState;
class TestGC {
protected:
CCGCScheduler& mScheduler;
public:
explicit TestGC(CCGCScheduler& aScheduler) : mScheduler(aScheduler) {}
void Run(int aNumSlices);
};
void TestGC::Run(int aNumSlices) {
// Make the purple buffer nearly empty so it is itself not an adequate reason
// for wanting a CC.
static_assert(3 < mozilla::kCCPurpleLimit);
SetNumSuspected(3);
// Running the GC should not influence whether a CC is currently seen as
// needed. But the first time we run GC, it will be false; later, we will
// have run a GC and set it to true.
CCReason neededCCAtStartOfGC =
mScheduler.IsCCNeeded(Now(), SuspectedCCObjects());
mScheduler.NoteGCBegin(JS::GCReason::API);
for (int slice = 0; slice < aNumSlices; slice++) {
EXPECT_TRUE(mScheduler.InIncrementalGC());
TimeStamp idleDeadline = Now() + kTenthSecond;
JS::SliceBudget budget =
mScheduler.ComputeInterSliceGCBudget(idleDeadline, Now());
TimeDuration budgetDuration =
TimeDuration::FromMilliseconds(budget.timeBudget());
EXPECT_NEAR(budgetDuration.ToSeconds(), 0.1, 1.e-6);
// Pretend the GC took exactly the budget.
AdvanceTime(budgetDuration);
EXPECT_EQ(mScheduler.IsCCNeeded(Now(), SuspectedCCObjects()),
neededCCAtStartOfGC);
// Mutator runs for 1 second.
AdvanceTime(kOneSecond);
}
mScheduler.NoteGCEnd();
mScheduler.SetNeedsFullGC(false);
}
class TestCC {
protected:
CCGCScheduler& mScheduler;
public:
explicit TestCC(CCGCScheduler& aScheduler) : mScheduler(aScheduler) {}
void Run(int aNumSlices) {
Prepare();
MaybePokeCC();
TimerFires(aNumSlices);
EndCycleCollectionCallback();
KillCCRunner();
}
virtual void Prepare() = 0;
virtual void MaybePokeCC();
virtual void TimerFires(int aNumSlices);
virtual void RunSlices(int aNumSlices);
virtual void RunSlice(TimeStamp aCCStartTime, TimeStamp aPrevSliceEnd,
int aSliceNum, int aNumSlices) = 0;
virtual void ForgetSkippable();
virtual void EndCycleCollectionCallback();
virtual void KillCCRunner();
};
void TestCC::MaybePokeCC() {
// nsJSContext::MaybePokeCC
// In all tests so far, we will be running this just after a GC.
CCReason reason = mScheduler.ShouldScheduleCC(Now(), SuspectedCCObjects());
EXPECT_EQ(reason, CCReason::GC_FINISHED);
mScheduler.InitCCRunnerStateMachine(CCRunnerState::ReducePurple, reason);
EXPECT_TRUE(mScheduler.IsEarlyForgetSkippable());
}
void TestCC::TimerFires(int aNumSlices) {
// Series of CCRunner timer fires.
CCRunnerStep step;
while (true) {
SuspectMore(1000);
TimeStamp idleDeadline = Now() + kOneSecond;
step =
mScheduler.AdvanceCCRunner(idleDeadline, Now(), SuspectedCCObjects());
// Should first see a series of ForgetSkippable actions.
if (step.mAction != CCRunnerAction::ForgetSkippable ||
step.mParam.mRemoveChildless != KeepChildless) {
break;
}
EXPECT_EQ(step.mYield, Yield);
ForgetSkippable();
}
while (step.mYield == Continue) {
TimeStamp idleDeadline = Now() + kOneSecond;
step =
mScheduler.AdvanceCCRunner(idleDeadline, Now(), SuspectedCCObjects());
}
EXPECT_EQ(step.mAction, CCRunnerAction::ForgetSkippable);
EXPECT_EQ(step.mParam.mRemoveChildless, RemoveChildless);
ForgetSkippable();
TimeStamp idleDeadline = Now() + kOneSecond;
step = mScheduler.AdvanceCCRunner(idleDeadline, Now(), SuspectedCCObjects());
EXPECT_EQ(step.mAction, CCRunnerAction::CleanupContentUnbinder);
step = mScheduler.AdvanceCCRunner(idleDeadline, Now(), SuspectedCCObjects());
EXPECT_EQ(step.mAction, CCRunnerAction::CleanupDeferred);
mScheduler.NoteCCBegin();
RunSlices(aNumSlices);
}
void TestCC::ForgetSkippable() {
// ...ForgetSkippable would happen here...
JS::SliceBudget budget =
mScheduler.ComputeForgetSkippableBudget(Now(), Now() + kTenthSecond);
EXPECT_NEAR(budget.timeBudget(), kTenthSecond.ToMilliseconds(), 1);
AdvanceTime(kTenthSecond);
mScheduler.NoteForgetSkippableComplete(Now(), SuspectedCCObjects());
}
void TestCC::RunSlices(int aNumSlices) {
TimeStamp ccStartTime = Now();
TimeStamp prevSliceEnd = ccStartTime;
for (int ccslice = 0; ccslice < aNumSlices; ccslice++) {
RunSlice(ccStartTime, prevSliceEnd, ccslice, aNumSlices);
prevSliceEnd = Now();
}
SetNumSuspected(0);
}
void TestCC::EndCycleCollectionCallback() {
// nsJSContext::EndCycleCollectionCallback
CycleCollectorResults results;
results.mFreedGCed = 10;
results.mFreedJSZones = 2;
mScheduler.NoteCCEnd(results, Now());
// Because > 0 zones were freed.
EXPECT_TRUE(mScheduler.NeedsGCAfterCC());
}
void TestCC::KillCCRunner() {
// nsJSContext::KillCCRunner
mScheduler.KillCCRunner();
}
class TestIdleCC : public TestCC {
public:
explicit TestIdleCC(CCGCScheduler& aScheduler) : TestCC(aScheduler) {}
void Prepare() override;
void RunSlice(TimeStamp aCCStartTime, TimeStamp aPrevSliceEnd, int aSliceNum,
int aNumSlices) override;
};
void TestIdleCC::Prepare() { EXPECT_TRUE(!mScheduler.InIncrementalGC()); }
void TestIdleCC::RunSlice(TimeStamp aCCStartTime, TimeStamp aPrevSliceEnd,
int aSliceNum, int aNumSlices) {
CCRunnerStep step;
TimeStamp idleDeadline = Now() + kTenthSecond;
// The scheduler should request a CycleCollect slice.
step = mScheduler.AdvanceCCRunner(idleDeadline, Now(), SuspectedCCObjects());
EXPECT_EQ(step.mAction, CCRunnerAction::CycleCollect);
// nsJSContext::RunCycleCollectorSlice
EXPECT_FALSE(mScheduler.InIncrementalGC());
bool preferShorter;
JS::SliceBudget budget = mScheduler.ComputeCCSliceBudget(
idleDeadline, aCCStartTime, aPrevSliceEnd, Now(), &preferShorter);
// The scheduler will set the budget to our deadline (0.1sec in the future).
EXPECT_NEAR(budget.timeBudget(), kTenthSecond.ToMilliseconds(), 1);
EXPECT_FALSE(preferShorter);
AdvanceTime(kTenthSecond);
}
class TestNonIdleCC : public TestCC {
public:
explicit TestNonIdleCC(CCGCScheduler& aScheduler) : TestCC(aScheduler) {}
void Prepare() override;
void RunSlice(TimeStamp aCCStartTime, TimeStamp aPrevSliceEnd, int aSliceNum,
int aNumSlices) override;
};
void TestNonIdleCC::Prepare() {
EXPECT_TRUE(!mScheduler.InIncrementalGC());
// Advance time by an hour to give time for a user event in the past.
AdvanceTime(TimeDuration::FromSeconds(3600));
}
void TestNonIdleCC::RunSlice(TimeStamp aCCStartTime, TimeStamp aPrevSliceEnd,
int aSliceNum, int aNumSlices) {
CCRunnerStep step;
TimeStamp nullDeadline;
// The scheduler should tell us to run a slice of cycle collection.
step = mScheduler.AdvanceCCRunner(nullDeadline, Now(), SuspectedCCObjects());
EXPECT_EQ(step.mAction, CCRunnerAction::CycleCollect);
// nsJSContext::RunCycleCollectorSlice
EXPECT_FALSE(mScheduler.InIncrementalGC());
bool preferShorter;
JS::SliceBudget budget = mScheduler.ComputeCCSliceBudget(
nullDeadline, aCCStartTime, aPrevSliceEnd, Now(), &preferShorter);
if (aSliceNum == 0) {
// First slice of the CC, so always use the baseBudget which is
// kICCSliceBudget (3ms) for a non-idle slice.
EXPECT_NEAR(budget.timeBudget(), kICCSliceBudget.ToMilliseconds(), 0.1);
} else if (aSliceNum == 1) {
// Second slice still uses the baseBudget, since not much time has passed
// so none of the lengthening mechanisms have kicked in yet.
EXPECT_NEAR(budget.timeBudget(), kICCSliceBudget.ToMilliseconds(), 0.1);
} else if (aSliceNum == 2) {
// We're not overrunning kMaxICCDuration, so we don't go unlimited.
EXPECT_FALSE(budget.isUnlimited());
// This slice is delayed, slice time should be increased.
EXPECT_NEAR(budget.timeBudget(),
MainThreadIdlePeriod::GetLongIdlePeriod() / 2, 0.1);
} else {
// We're not overrunning kMaxICCDuration, so we don't go unlimited.
EXPECT_FALSE(budget.isUnlimited());
// These slices are not delayed, but enough time has passed that the
// dominating factor is now the linear ramp up to max slice time at the
// halfway point to kMaxICCDuration.
EXPECT_TRUE(budget.timeBudget() > kICCSliceBudget.ToMilliseconds());
EXPECT_TRUE(budget.timeBudget() <=
MainThreadIdlePeriod::GetLongIdlePeriod());
}
EXPECT_TRUE(preferShorter); // Non-idle prefers shorter slices
AdvanceTime(TimeDuration::FromMilliseconds(budget.timeBudget()));
if (aSliceNum == 1) {
// Delay the third slice (only).
AdvanceTime(kICCIntersliceDelay * 2);
}
}
// Do a GC then CC then GC.
static bool BasicScenario(CCGCScheduler& aScheduler, TestGC* aTestGC,
TestCC* aTestCC) {
// Run a 10-slice incremental GC.
aTestGC->Run(10);
// After a GC, the scheduler should decide to do a full CC regardless of the
// number of purple buffer entries.
SetNumSuspected(3);
EXPECT_EQ(aScheduler.IsCCNeeded(Now(), SuspectedCCObjects()),
CCReason::GC_FINISHED);
// Now we should want to CC.
EXPECT_EQ(aScheduler.ShouldScheduleCC(Now(), SuspectedCCObjects()),
CCReason::GC_FINISHED);
// Do a 5-slice CC.
aTestCC->Run(5);
// Not enough suspected objects to deserve a CC.
EXPECT_EQ(aScheduler.IsCCNeeded(Now(), SuspectedCCObjects()),
CCReason::NO_REASON);
EXPECT_EQ(aScheduler.ShouldScheduleCC(Now(), SuspectedCCObjects()),
CCReason::NO_REASON);
SetNumSuspected(10000);
// We shouldn't want to CC again yet, it's too soon.
EXPECT_EQ(aScheduler.ShouldScheduleCC(Now(), SuspectedCCObjects()),
CCReason::NO_REASON);
AdvanceTime(mozilla::kCCDelay);
// *Now* it's time for another CC.
EXPECT_EQ(aScheduler.ShouldScheduleCC(Now(), SuspectedCCObjects()),
CCReason::MANY_SUSPECTED);
// Run a 3-slice incremental GC.
EXPECT_TRUE(!aScheduler.InIncrementalGC());
aTestGC->Run(3);
return true;
}
MOZ_RUNINIT static CCGCScheduler scheduler;
MOZ_RUNINIT static TestGC gc(scheduler);
MOZ_RUNINIT static TestIdleCC ccIdle(scheduler);
MOZ_RUNINIT static TestNonIdleCC ccNonIdle(scheduler);
TEST(TestScheduler, Idle)
{
// Cannot CC until we GC once.
EXPECT_EQ(scheduler.ShouldScheduleCC(Now(), SuspectedCCObjects()),
CCReason::NO_REASON);
EXPECT_TRUE(BasicScenario(scheduler, &gc, &ccIdle));
}
TEST(TestScheduler, NonIdle)
{ EXPECT_TRUE(BasicScenario(scheduler, &gc, &ccNonIdle)); }