Dactyloidae/xpcom/base/SlowAsynchronousTaskScheduler.cpp
win7-7 3bbee255fd Revert "Compiles and does not crash."
This reverts commit 48ba811bd6bed8b75d223eddf74c0785e7e81efd.
2026-08-01 03:14:09 +01:00

371 lines
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9.8 KiB
C++

/* -*- Mode: C++; tab-width: 8; 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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "SlowAsynchronousTaskScheduler.h"
#include "mozilla/TimeStamp.h"
#include "nsComponentManagerUtils.h"
//#define DEBUG_SATS 1
using namespace mozilla;
// If we're expecting a tick to happen soon, don't use timer based tick.
static const uint32_t kExpectedTimeOverlapLimit = 10;
SlowAsynchronousTaskScheduler::SlowAsynchronousTaskScheduler()
: mShuttingDown(false)
{
}
SlowAsynchronousTaskScheduler::~SlowAsynchronousTaskScheduler()
{
MOZ_ASSERT(!mTimer);
while (ScheduledSlowTask* task = mScheduledSlowTasks.popFirst()) {
delete task;
}
}
void
SlowAsynchronousTaskScheduler::ExpectedTick(uint32_t aMillisecondsFromNow)
{
TimeStamp newExpectedTick = FromNow(aMillisecondsFromNow);
if (mExpectedNonTimerTick.IsNull() ||
newExpectedTick < mExpectedNonTimerTick) {
mExpectedNonTimerTick = newExpectedTick;
}
}
void
SlowAsynchronousTaskScheduler::Tick(bool aFromTimer)
{
CancelTimer();
if (mScheduledSlowTasks.isEmpty()) {
if (!aFromTimer) {
mExpectedNonTimerTick = TimeStamp();
}
return;
}
TimeStamp now = TimeStamp::Now();
TimeDuration limit =
TimeDuration::FromMilliseconds(
static_cast<double>(kExpectedTimeOverlapLimit));
// We have a tick from timer, but we're possibly waiting for a non-timer
// tick happening real soon. If so, don't handle this tick.
if (aFromTimer && !mExpectedNonTimerTick.IsNull() &&
now < mExpectedNonTimerTick &&
now + limit > mExpectedNonTimerTick) {
// Try to run the timer right after the expected tick, since
// the expected tick might get lost.
uint32_t newTimerValue =
static_cast<uint32_t>((mExpectedNonTimerTick - now).ToMilliseconds()) + 1;
EnsureTimer(newTimerValue);
return;
}
mExpectedNonTimerTick = TimeStamp();
ScheduledSlowTask* current = mScheduledSlowTasks.popFirst();
if (!current) {
return;
}
if (current->mRunnable) {
#ifdef DEBUG_SATS
printf("SlowAsynchronousTaskScheduler::Tick[timer=%s], runnable \n",
aFromTimer ? "true" : "false");
#endif
nsCOMPtr<nsIRunnable> runnable;
runnable.swap(current->mRunnable);
delete current;
current = nullptr;
runnable->Run();
} else {
#ifdef DEBUG_SATS
printf("SlowAsynchronousTaskScheduler::Tick[timer=%s] task=%p ",
aFromTimer ? "true" : "false", current->mSlowTasks);
for (uint32_t i = 0; current->mSlowTasks[i].mCallback; ++i) {
printf("[%u]", current->mSlowTasks[i].mID);
}
#endif
DependentSlowTask& task =
current->mSlowTasks[current->mIndexOfNextTask];
#ifdef DEBUG_SATS
printf(", will run id=%u\n", task.mID);
#endif
// Run the currently scheduled task, and store state of the next task.
void* data = current->mDataForNextTask;
current->mDataForNextTask = nullptr;
SATSState nextState = task.mCallback(task.mID, data);
uint32_t nextID = nextState.mState;
uint32_t i = 0;
for (; current->mSlowTasks[i].mCallback; ++i) {
if (current->mSlowTasks[i].mID == nextID) {
break;
}
}
// The nextID did point to another task which has a callback to run.
// Schedule that.
if (current->mSlowTasks[i].mCallback) {
current->mIndexOfNextTask = i;
current->mDataForNextTask = nextState.mData;
// Reschedule, since it now has new mIndexOfNextTask.
AddScheduledSlowTask(current, current->mSlowTasks[i].mDelayMillis);
} else {
// Couldn't find anything to schedule.
delete current;
}
}
// Make sure we have a timer running if we have something scheduled.
ScheduledSlowTask* first = mScheduledSlowTasks.getFirst();
if (first) {
#ifdef DEBUG_SATS
printf("Ensuring timer for the next task\n");
#endif
uint32_t millis = first->mExpectedTimeToRun > now ?
static_cast<uint32_t>(
(first->mExpectedTimeToRun - now).ToMilliseconds()) :
0;
EnsureTimer(millis);
}
}
void
SlowAsynchronousTaskScheduler::Schedule(nsIRunnable* aRunnable,
uint32_t aMillis)
{
#ifdef DEBUG_SATS
printf("SlowAsynchronousTaskScheduler::Schedule aRunnable\n");
#endif
AddScheduledSlowTask(new ScheduledSlowTask(aRunnable), aMillis);
EnsureTimer(aMillis);
}
void
SlowAsynchronousTaskScheduler::Schedule(DependentSlowTask* aTasks,
void* aData)
{
#ifdef DEBUG_SATS
printf("SlowAsynchronousTaskScheduler::Schedule aTasks ");
for (uint32_t i = 0; aTasks[i].mCallback; ++i) {
printf("[%u]", aTasks[i].mID);
}
printf("\n");
#endif
MOZ_ASSERT(aTasks && aTasks[0].mCallback);
AddScheduledSlowTask(new ScheduledSlowTask(aTasks, 0, aData),
aTasks[0].mDelayMillis);
EnsureTimer(aTasks[0].mDelayMillis);
}
void
SlowAsynchronousTaskScheduler::Schedule(DependentSlowTask* aTasks,
uint32_t aID, void* aData)
{
#ifdef DEBUG_SATS
printf("SlowAsynchronousTaskScheduler::Schedule aTask ");
for (uint32_t i = 0; aTasks[i].mCallback; ++i) {
printf("[%u]", aTasks[i].mID);
}
printf(", scheduling=%u\n", aID);
#endif
for (uint32_t i = 0; aTasks[i].mCallback; ++i) {
if (aTasks[i].mID == aID) {
MOZ_ASSERT(aTasks[i].mCallback);
AddScheduledSlowTask(new ScheduledSlowTask(aTasks, i, aData),
aTasks[i].mDelayMillis);
EnsureTimer(aTasks[i].mDelayMillis);
return;
}
}
MOZ_ASSERT(false, "Unknown ID?");
}
void
SlowAsynchronousTaskScheduler::CancelScheduledTask(nsIRunnable* aRunnable)
{
if (aRunnable) {
ScheduledSlowTask* task = mScheduledSlowTasks.getFirst();
while(task) {
ScheduledSlowTask* next = task->getNext();
if (task->mRunnable == aRunnable) {
task->remove();
delete task;
}
task = next;
}
}
}
void
SlowAsynchronousTaskScheduler::CancelScheduledTask(DependentSlowTask* aTasks)
{
if (aTasks) {
ScheduledSlowTask* task = mScheduledSlowTasks.getFirst();
while(task) {
ScheduledSlowTask* next = task->getNext();
if (task->mSlowTasks == aTasks) {
task->remove();
delete task;
}
task = next;
}
}
}
void
SlowAsynchronousTaskScheduler::CancelScheduledTask(DependentSlowTask* aTasks,
uint32_t aID)
{
if (aTasks) {
ScheduledSlowTask* task = mScheduledSlowTasks.getFirst();
while(task) {
ScheduledSlowTask* next = task->getNext();
if (task->mSlowTasks == aTasks &&
task->mSlowTasks[task->mIndexOfNextTask].mID == aID) {
task->remove();
delete task;
}
task = next;
}
}
}
bool
SlowAsynchronousTaskScheduler::IsScheduled(nsIRunnable* aRunnable)
{
if (aRunnable) {
ScheduledSlowTask* task = mScheduledSlowTasks.getFirst();
while(task) {
if (task->mRunnable == aRunnable) {
return true;
}
task = task->getNext();
}
}
return false;
}
bool
SlowAsynchronousTaskScheduler::IsScheduled(DependentSlowTask* aTasks)
{
if (aTasks) {
ScheduledSlowTask* task = mScheduledSlowTasks.getFirst();
while(task) {
if (task->mSlowTasks == aTasks) {
return true;
}
task = task->getNext();
}
}
return false;
}
bool
SlowAsynchronousTaskScheduler::IsScheduled(DependentSlowTask* aTasks,
uint32_t aID)
{
if (aTasks) {
ScheduledSlowTask* task = mScheduledSlowTasks.getFirst();
while(task) {
if (task->mSlowTasks == aTasks &&
task->mSlowTasks[task->mIndexOfNextTask].mID == aID) {
return true;
}
task = task->getNext();
}
}
return false;
}
class SATSTimerTick : public CancelableRunnable
{
public:
NS_IMETHOD Run()
{
if (!mCancelled) {
SlowAsynchronousTaskScheduler* sats =
CycleCollectedJSContext::GetScheduler();
if (sats) {
sats->TickFromTimer();
}
}
return NS_OK;
}
NS_IMETHOD Cancel()
{
mCancelled = true;
return NS_OK;
}
bool mCancelled = false;
};
void
SlowAsynchronousTaskScheduler::EnsureTimer(uint32_t aMillis)
{
#ifdef DEBUG_SATS
printf("SlowAsynchronousTaskScheduler::EnsureTimer %ums\n", aMillis);
#endif
TimeStamp fromNow = FromNow(aMillis);
if (mTimer) {
if (!mTimerTime.IsNull() && mTimerTime < fromNow) {
// We will run the timer sooner than aMillis from now.
return;
}
mTimer->Cancel();
} else {
if (mShuttingDown) {
return;
}
mTimer = do_CreateInstance("@mozilla.org/timer;1");
if (!mTimer) {
NS_WARNING("No timer!");
return;
}
mTimerCallback = new SATSTimerTick();
}
mTimerTime = fromNow;
CycleCollectedJSContext::ScheduleTimer(mTimer, mTimerCallback, aMillis);
}
void
SlowAsynchronousTaskScheduler::AddScheduledSlowTask(ScheduledSlowTask* aTask,
uint32_t aMillis)
{
TimeStamp expectedTime = FromNow(aMillis);
ScheduledSlowTask* task = mScheduledSlowTasks.getFirst();
while(task) {
if (task->mExpectedTimeToRun > expectedTime) {
task->setPrevious(aTask);
break;
}
task = task->getNext();
}
if (!task) {
mScheduledSlowTasks.insertBack(aTask);
}
aTask->mExpectedTimeToRun = expectedTime;
}
void
SlowAsynchronousTaskScheduler::CancelTimer()
{
if (mTimer) {
mTimer->Cancel();
mTimerTime = TimeStamp();
}
}