gecko/dom/ipc/PreallocatedProcessManager.cpp
Justin Lebar a201fa0e2a Bug 844323 - Part 1: Move process preallocation logic out of ContentParent and into a new file, PreallocatedProcessManager. r=bent
Also make the PreallocatedProcessManager respond to pref changes.  This allows us to write a test involving the preallocated process.  Making this change was the main motivation for this patch; I moved the logic out of ContentParent because with the pref-watching code it was becoming unweildy.
2013-04-25 20:53:26 -04:00

230 lines
5.2 KiB
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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set sw=2 ts=8 et ft=cpp : */
/* 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 "mozilla/PreallocatedProcessManager.h"
#include "mozilla/ClearOnShutdown.h"
#include "mozilla/Preferences.h"
#include "mozilla/dom/ContentParent.h"
using namespace mozilla;
using namespace mozilla::hal;
using namespace mozilla::dom;
namespace {
/**
* This singleton class implements the static methods on
* PreallocatedProcessManager.
*/
class PreallocatedProcessManagerImpl MOZ_FINAL
: public nsIObserver
{
public:
static PreallocatedProcessManagerImpl* Singleton();
NS_DECL_ISUPPORTS
NS_DECL_NSIOBSERVER
// See comments on PreallocatedProcessManager for these methods.
void AllocateAfterDelay();
void AllocateOnIdle();
void AllocateNow();
already_AddRefed<ContentParent> Take();
private:
static mozilla::StaticRefPtr<PreallocatedProcessManagerImpl> sSingleton;
PreallocatedProcessManagerImpl();
DISALLOW_EVIL_CONSTRUCTORS(PreallocatedProcessManagerImpl);
void Init();
void RereadPrefs();
void Enable();
void Disable();
void ObserveProcessShutdown(nsISupports* aSubject);
bool mEnabled;
nsRefPtr<ContentParent> mPreallocatedAppProcess;
};
/* static */ StaticRefPtr<PreallocatedProcessManagerImpl>
PreallocatedProcessManagerImpl::sSingleton;
/* static */ PreallocatedProcessManagerImpl*
PreallocatedProcessManagerImpl::Singleton()
{
if (!sSingleton) {
sSingleton = new PreallocatedProcessManagerImpl();
sSingleton->Init();
ClearOnShutdown(&sSingleton);
}
return sSingleton;
}
NS_IMPL_ISUPPORTS1(PreallocatedProcessManagerImpl, nsIObserver)
PreallocatedProcessManagerImpl::PreallocatedProcessManagerImpl()
: mEnabled(false)
{}
void
PreallocatedProcessManagerImpl::Init()
{
Preferences::AddStrongObserver(this, "dom.ipc.processPrelaunch.enabled");
nsCOMPtr<nsIObserverService> os = services::GetObserverService();
if (os) {
os->AddObserver(this, "ipc:content-shutdown",
/* weakRef = */ false);
}
RereadPrefs();
}
NS_IMETHODIMP
PreallocatedProcessManagerImpl::Observe(nsISupports* aSubject,
const char* aTopic,
const PRUnichar* aData)
{
if (!strcmp("ipc:content-shutdown", aTopic)) {
ObserveProcessShutdown(aSubject);
} else if (!strcmp("nsPref:changed", aTopic)) {
// The only other observer we registered was for our prefs.
RereadPrefs();
} else {
MOZ_ASSERT(false);
}
return NS_OK;
}
void
PreallocatedProcessManagerImpl::RereadPrefs()
{
if (Preferences::GetBool("dom.ipc.processPrelaunch.enabled")) {
Enable();
} else {
Disable();
}
}
already_AddRefed<ContentParent>
PreallocatedProcessManagerImpl::Take()
{
return mPreallocatedAppProcess.forget();
}
void
PreallocatedProcessManagerImpl::Enable()
{
if (mEnabled) {
return;
}
mEnabled = true;
AllocateAfterDelay();
}
void
PreallocatedProcessManagerImpl::AllocateAfterDelay()
{
if (!mEnabled || mPreallocatedAppProcess) {
return;
}
MessageLoop::current()->PostDelayedTask(
FROM_HERE,
NewRunnableMethod(this, &PreallocatedProcessManagerImpl::AllocateOnIdle),
Preferences::GetUint("dom.ipc.processPrelaunch.delayMs", 1000));
}
void
PreallocatedProcessManagerImpl::AllocateOnIdle()
{
if (!mEnabled || mPreallocatedAppProcess) {
return;
}
MessageLoop::current()->PostIdleTask(
FROM_HERE,
NewRunnableMethod(this, &PreallocatedProcessManagerImpl::AllocateNow));
}
void
PreallocatedProcessManagerImpl::AllocateNow()
{
if (!mEnabled || mPreallocatedAppProcess) {
return;
}
mPreallocatedAppProcess = ContentParent::PreallocateAppProcess();
}
void
PreallocatedProcessManagerImpl::Disable()
{
if (!mEnabled) {
return;
}
mEnabled = false;
if (mPreallocatedAppProcess) {
mPreallocatedAppProcess->ShutDown();
mPreallocatedAppProcess = nullptr;
}
}
void
PreallocatedProcessManagerImpl::ObserveProcessShutdown(nsISupports* aSubject)
{
if (!mPreallocatedAppProcess) {
return;
}
nsCOMPtr<nsIPropertyBag2> props = do_QueryInterface(aSubject);
NS_ENSURE_TRUE_VOID(props);
uint64_t childID = CONTENT_PROCESS_ID_UNKNOWN;
props->GetPropertyAsUint64(NS_LITERAL_STRING("childID"), &childID);
NS_ENSURE_TRUE_VOID(childID != CONTENT_PROCESS_ID_UNKNOWN);
if (childID == mPreallocatedAppProcess->ChildID()) {
mPreallocatedAppProcess = nullptr;
}
}
} // anonymous namespace
namespace mozilla {
/* static */ void
PreallocatedProcessManager::AllocateAfterDelay()
{
PreallocatedProcessManagerImpl::Singleton()->AllocateAfterDelay();
}
/* static */ void
PreallocatedProcessManager::AllocateOnIdle()
{
PreallocatedProcessManagerImpl::Singleton()->AllocateOnIdle();
}
/* static */ void
PreallocatedProcessManager::AllocateNow()
{
PreallocatedProcessManagerImpl::Singleton()->AllocateNow();
}
/* static */ already_AddRefed<ContentParent>
PreallocatedProcessManager::Take()
{
return PreallocatedProcessManagerImpl::Singleton()->Take();
}
} // namespace mozilla