gecko/dom/indexedDB/TransactionThreadPool.cpp

611 lines
18 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Indexed Database.
*
* The Initial Developer of the Original Code is
* The Mozilla Foundation.
* Portions created by the Initial Developer are Copyright (C) 2010
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Ben Turner <bent.mozilla@gmail.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "TransactionThreadPool.h"
#include "nsIObserverService.h"
#include "nsIThreadPool.h"
#include "nsComponentManagerUtils.h"
#include "nsThreadUtils.h"
#include "nsServiceManagerUtils.h"
#include "nsXPCOMCIDInternal.h"
using mozilla::MutexAutoLock;
using mozilla::MutexAutoUnlock;
USING_INDEXEDDB_NAMESPACE
namespace {
const PRUint32 kThreadLimit = 20;
const PRUint32 kIdleThreadLimit = 5;
const PRUint32 kIdleThreadTimeoutMs = 30000;
TransactionThreadPool* gInstance = nsnull;
bool gShutdown = false;
inline
nsresult
CheckOverlapAndMergeObjectStores(nsTArray<nsString>& aLockedStores,
const nsTArray<nsString>& aObjectStores,
bool aShouldMerge,
bool* aStoresOverlap)
{
PRUint32 length = aObjectStores.Length();
bool overlap = false;
for (PRUint32 index = 0; index < length; index++) {
const nsString& storeName = aObjectStores[index];
if (aLockedStores.Contains(storeName)) {
overlap = true;
}
else if (aShouldMerge && !aLockedStores.AppendElement(storeName)) {
NS_WARNING("Out of memory!");
return NS_ERROR_OUT_OF_MEMORY;
}
}
*aStoresOverlap = overlap;
return NS_OK;
}
} // anonymous namespace
BEGIN_INDEXEDDB_NAMESPACE
class FinishTransactionRunnable : public nsIRunnable
{
public:
NS_DECL_ISUPPORTS
NS_DECL_NSIRUNNABLE
inline FinishTransactionRunnable(IDBTransaction* aTransaction,
nsCOMPtr<nsIRunnable>& aFinishRunnable);
private:
IDBTransaction* mTransaction;
nsCOMPtr<nsIRunnable> mFinishRunnable;
};
END_INDEXEDDB_NAMESPACE
TransactionThreadPool::TransactionThreadPool()
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
NS_ASSERTION(!gInstance, "More than one instance!");
}
TransactionThreadPool::~TransactionThreadPool()
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
NS_ASSERTION(!gInstance, "More than one instance!");
}
// static
TransactionThreadPool*
TransactionThreadPool::GetOrCreate()
{
if (!gInstance && !gShutdown) {
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
nsRefPtr<TransactionThreadPool> pool(new TransactionThreadPool());
nsresult rv = pool->Init();
NS_ENSURE_SUCCESS(rv, nsnull);
nsCOMPtr<nsIObserverService> obs =
do_GetService(NS_OBSERVERSERVICE_CONTRACTID, &rv);
NS_ENSURE_SUCCESS(rv, nsnull);
rv = obs->AddObserver(pool, "xpcom-shutdown-threads", PR_FALSE);
NS_ENSURE_SUCCESS(rv, nsnull);
// The observer service now owns us.
gInstance = pool;
}
return gInstance;
}
// static
void
TransactionThreadPool::Shutdown()
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
gShutdown = true;
if (gInstance) {
if (NS_FAILED(gInstance->Cleanup())) {
NS_WARNING("Failed to shutdown thread pool!");
}
gInstance = nsnull;
}
}
nsresult
TransactionThreadPool::Init()
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
if (!mTransactionsInProgress.Init()) {
NS_WARNING("Failed to init hash!");
return NS_ERROR_FAILURE;
}
nsresult rv;
mThreadPool = do_CreateInstance(NS_THREADPOOL_CONTRACTID, &rv);
NS_ENSURE_SUCCESS(rv, rv);
rv = mThreadPool->SetThreadLimit(kThreadLimit);
NS_ENSURE_SUCCESS(rv, rv);
rv = mThreadPool->SetIdleThreadLimit(kIdleThreadLimit);
NS_ENSURE_SUCCESS(rv, rv);
rv = mThreadPool->SetIdleThreadTimeout(kIdleThreadTimeoutMs);
NS_ENSURE_SUCCESS(rv, rv);
return NS_OK;
}
nsresult
TransactionThreadPool::Cleanup()
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
if (mTransactionsInProgress.Count()) {
// This is actually really bad, but if we don't force everything awake then
// we will deadlock on shutdown...
NS_ERROR("Transactions still in progress!");
}
nsresult rv = mThreadPool->Shutdown();
NS_ENSURE_SUCCESS(rv, rv);
return NS_OK;
}
void
TransactionThreadPool::FinishTransaction(IDBTransaction* aTransaction)
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
NS_ASSERTION(aTransaction, "Null pointer!");
// AddRef here because removing from the hash will call Release.
nsRefPtr<IDBTransaction> transaction(aTransaction);
const PRUint32 databaseId = aTransaction->mDatabase->Id();
DatabaseTransactionInfo* dbTransactionInfo;
if (!mTransactionsInProgress.Get(databaseId, &dbTransactionInfo)) {
NS_ERROR("We don't know anyting about this database?!");
return;
}
nsTArray<TransactionInfo>& transactionsInProgress =
dbTransactionInfo->transactions;
PRUint32 transactionCount = transactionsInProgress.Length();
#ifdef DEBUG
if (aTransaction->mMode == IDBTransaction::FULL_LOCK) {
NS_ASSERTION(dbTransactionInfo->locked, "Should be locked!");
NS_ASSERTION(transactionCount == 1,
"More transactions running than should be!");
}
#endif
if (transactionCount == 1) {
#ifdef DEBUG
{
TransactionInfo& info = transactionsInProgress[0];
NS_ASSERTION(info.transaction == aTransaction, "Transaction mismatch!");
}
#endif
mTransactionsInProgress.Remove(databaseId);
}
else {
// We need to rebuild the locked object store list.
nsTArray<nsString> storesWriting, storesReading;
for (PRUint32 index = 0, count = transactionCount; index < count; index++) {
IDBTransaction* transaction = transactionsInProgress[index].transaction;
if (transaction == aTransaction) {
NS_ASSERTION(count == transactionCount, "More than one match?!");
transactionsInProgress.RemoveElementAt(index);
index--;
count--;
continue;
}
const nsTArray<nsString>& objectStores = transaction->mObjectStoreNames;
bool dummy;
if (transaction->mMode == nsIIDBTransaction::READ_WRITE) {
if (NS_FAILED(CheckOverlapAndMergeObjectStores(storesWriting,
objectStores,
true, &dummy))) {
NS_WARNING("Out of memory!");
}
}
else if (transaction->mMode == nsIIDBTransaction::READ_ONLY) {
if (NS_FAILED(CheckOverlapAndMergeObjectStores(storesReading,
objectStores,
true, &dummy))) {
NS_WARNING("Out of memory!");
}
}
else {
NS_NOTREACHED("Unknown mode!");
}
}
NS_ASSERTION(transactionsInProgress.Length() == transactionCount - 1,
"Didn't find the transaction we were looking for!");
dbTransactionInfo->storesWriting.SwapElements(storesWriting);
dbTransactionInfo->storesReading.SwapElements(storesReading);
}
// Try to dispatch all the queued transactions again.
nsTArray<QueuedDispatchInfo> queuedDispatch;
queuedDispatch.SwapElements(mDelayedDispatchQueue);
transactionCount = queuedDispatch.Length();
for (PRUint32 index = 0; index < transactionCount; index++) {
if (NS_FAILED(Dispatch(queuedDispatch[index]))) {
NS_WARNING("Dispatch failed!");
}
}
}
nsresult
TransactionThreadPool::TransactionCanRun(IDBTransaction* aTransaction,
bool* aCanRun,
TransactionQueue** aExistingQueue)
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
NS_ASSERTION(aTransaction, "Null pointer!");
NS_ASSERTION(aCanRun, "Null pointer!");
NS_ASSERTION(aExistingQueue, "Null pointer!");
const PRUint32 databaseId = aTransaction->mDatabase->Id();
const nsTArray<nsString>& objectStoreNames = aTransaction->mObjectStoreNames;
const PRUint16 mode = aTransaction->mMode;
// See if we can run this transaction now.
DatabaseTransactionInfo* dbTransactionInfo;
if (!mTransactionsInProgress.Get(databaseId, &dbTransactionInfo)) {
// First transaction for this database, fine to run.
*aCanRun = true;
*aExistingQueue = nsnull;
return NS_OK;
}
nsTArray<TransactionInfo>& transactionsInProgress =
dbTransactionInfo->transactions;
PRUint32 transactionCount = transactionsInProgress.Length();
NS_ASSERTION(transactionCount, "Should never be 0!");
if (mode == IDBTransaction::FULL_LOCK) {
dbTransactionInfo->lockPending = true;
}
for (PRUint32 index = 0; index < transactionCount; index++) {
// See if this transaction is in out list of current transactions.
const TransactionInfo& info = transactionsInProgress[index];
if (info.transaction == aTransaction) {
*aCanRun = true;
*aExistingQueue = info.queue;
return NS_OK;
}
}
if (dbTransactionInfo->locked || dbTransactionInfo->lockPending) {
*aCanRun = false;
*aExistingQueue = nsnull;
return NS_OK;
}
bool writeOverlap;
nsresult rv =
CheckOverlapAndMergeObjectStores(dbTransactionInfo->storesWriting,
objectStoreNames,
mode == nsIIDBTransaction::READ_WRITE,
&writeOverlap);
NS_ENSURE_SUCCESS(rv, rv);
bool readOverlap;
rv = CheckOverlapAndMergeObjectStores(dbTransactionInfo->storesReading,
objectStoreNames,
mode == nsIIDBTransaction::READ_ONLY,
&readOverlap);
NS_ENSURE_SUCCESS(rv, rv);
if (writeOverlap ||
(readOverlap && mode == nsIIDBTransaction::READ_WRITE)) {
*aCanRun = false;
*aExistingQueue = nsnull;
return NS_OK;
}
*aCanRun = true;
*aExistingQueue = nsnull;
return NS_OK;
}
nsresult
TransactionThreadPool::Dispatch(IDBTransaction* aTransaction,
nsIRunnable* aRunnable,
bool aFinish,
nsIRunnable* aFinishRunnable)
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
NS_ASSERTION(aTransaction, "Null pointer!");
NS_ASSERTION(aRunnable, "Null pointer!");
bool canRun;
TransactionQueue* existingQueue;
nsresult rv = TransactionCanRun(aTransaction, &canRun, &existingQueue);
NS_ENSURE_SUCCESS(rv, rv);
if (!canRun) {
QueuedDispatchInfo* info = mDelayedDispatchQueue.AppendElement();
NS_ENSURE_TRUE(info, NS_ERROR_OUT_OF_MEMORY);
info->transaction = aTransaction;
info->runnable = aRunnable;
info->finish = aFinish;
info->finishRunnable = aFinishRunnable;
return NS_OK;
}
if (existingQueue) {
existingQueue->Dispatch(aRunnable);
if (aFinish) {
existingQueue->Finish(aFinishRunnable);
}
return NS_OK;
}
const PRUint32 databaseId = aTransaction->mDatabase->Id();
#ifdef DEBUG
if (aTransaction->mMode == IDBTransaction::FULL_LOCK) {
NS_ASSERTION(!mTransactionsInProgress.Get(databaseId, nsnull),
"Shouldn't have anything in progress!");
}
#endif
DatabaseTransactionInfo* dbTransactionInfo;
nsAutoPtr<DatabaseTransactionInfo> autoDBTransactionInfo;
if (!mTransactionsInProgress.Get(databaseId, &dbTransactionInfo)) {
// Make a new struct for this transaction.
autoDBTransactionInfo = new DatabaseTransactionInfo();
dbTransactionInfo = autoDBTransactionInfo;
}
if (aTransaction->mMode == IDBTransaction::FULL_LOCK) {
NS_ASSERTION(!dbTransactionInfo->locked, "Already locked?!");
dbTransactionInfo->locked = true;
}
const nsTArray<nsString>& objectStoreNames = aTransaction->mObjectStoreNames;
nsTArray<nsString>& storesInUse =
aTransaction->mMode == nsIIDBTransaction::READ_WRITE ?
dbTransactionInfo->storesWriting :
dbTransactionInfo->storesReading;
if (!storesInUse.AppendElements(objectStoreNames)) {
NS_WARNING("Out of memory!");
return NS_ERROR_OUT_OF_MEMORY;
}
nsTArray<TransactionInfo>& transactionInfoArray =
dbTransactionInfo->transactions;
TransactionInfo* transactionInfo = transactionInfoArray.AppendElement();
NS_ENSURE_TRUE(transactionInfo, NS_ERROR_OUT_OF_MEMORY);
transactionInfo->transaction = aTransaction;
transactionInfo->queue = new TransactionQueue(aTransaction, aRunnable);
if (aFinish) {
transactionInfo->queue->Finish(aFinishRunnable);
}
if (!transactionInfo->objectStoreNames.AppendElements(objectStoreNames)) {
NS_WARNING("Out of memory!");
return NS_ERROR_OUT_OF_MEMORY;
}
if (autoDBTransactionInfo) {
if (!mTransactionsInProgress.Put(databaseId, autoDBTransactionInfo)) {
NS_WARNING("Failed to put!");
return NS_ERROR_OUT_OF_MEMORY;
}
autoDBTransactionInfo.forget();
}
return mThreadPool->Dispatch(transactionInfo->queue, NS_DISPATCH_NORMAL);
}
NS_IMPL_THREADSAFE_ISUPPORTS1(TransactionThreadPool, nsIObserver)
NS_IMETHODIMP
TransactionThreadPool::Observe(nsISupports* /* aSubject */,
const char* aTopic,
const PRUnichar* /* aData */)
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
NS_ASSERTION(!strcmp("xpcom-shutdown-threads", aTopic), "Wrong topic!");
Shutdown();
return NS_OK;
}
TransactionThreadPool::
TransactionQueue::TransactionQueue(IDBTransaction* aTransaction,
nsIRunnable* aRunnable)
: mMutex("TransactionQueue::mMutex"),
mCondVar(mMutex, "TransactionQueue::mCondVar"),
mTransaction(aTransaction),
mShouldFinish(false)
{
NS_ASSERTION(aTransaction, "Null pointer!");
NS_ASSERTION(aRunnable, "Null pointer!");
mQueue.AppendElement(aRunnable);
}
void
TransactionThreadPool::TransactionQueue::Dispatch(nsIRunnable* aRunnable)
{
MutexAutoLock lock(mMutex);
NS_ASSERTION(!mShouldFinish, "Dispatch called after Finish!");
if (!mQueue.AppendElement(aRunnable)) {
MutexAutoUnlock unlock(mMutex);
NS_RUNTIMEABORT("Out of memory!");
}
mCondVar.Notify();
}
void
TransactionThreadPool::TransactionQueue::Finish(nsIRunnable* aFinishRunnable)
{
MutexAutoLock lock(mMutex);
NS_ASSERTION(!mShouldFinish, "Finish called more than once!");
mShouldFinish = true;
mFinishRunnable = aFinishRunnable;
mCondVar.Notify();
}
NS_IMPL_THREADSAFE_ISUPPORTS1(TransactionThreadPool::TransactionQueue,
nsIRunnable)
NS_IMETHODIMP
TransactionThreadPool::TransactionQueue::Run()
{
nsAutoTArray<nsCOMPtr<nsIRunnable>, 10> queue;
nsCOMPtr<nsIRunnable> finishRunnable;
bool shouldFinish = false;
while(!shouldFinish) {
NS_ASSERTION(queue.IsEmpty(), "Should have cleared this!");
{
MutexAutoLock lock(mMutex);
while (!mShouldFinish && mQueue.IsEmpty()) {
if (NS_FAILED(mCondVar.Wait())) {
NS_ERROR("Failed to wait!");
}
}
mQueue.SwapElements(queue);
if (mShouldFinish) {
mFinishRunnable.swap(finishRunnable);
shouldFinish = true;
}
}
PRUint32 count = queue.Length();
for (PRUint32 index = 0; index < count; index++) {
nsCOMPtr<nsIRunnable>& runnable = queue[index];
runnable->Run();
runnable = nsnull;
}
if (count) {
queue.Clear();
}
}
nsCOMPtr<nsIRunnable> finishTransactionRunnable =
new FinishTransactionRunnable(mTransaction, finishRunnable);
if (NS_FAILED(NS_DispatchToMainThread(finishTransactionRunnable,
NS_DISPATCH_NORMAL))) {
NS_WARNING("Failed to dispatch finishTransactionRunnable!");
}
return NS_OK;
}
FinishTransactionRunnable::FinishTransactionRunnable(
IDBTransaction* aTransaction,
nsCOMPtr<nsIRunnable>& aFinishRunnable)
: mTransaction(aTransaction)
{
NS_ASSERTION(!NS_IsMainThread(), "Wrong thread!");
NS_ASSERTION(aTransaction, "Null pointer!");
mFinishRunnable.swap(aFinishRunnable);
}
NS_IMPL_THREADSAFE_ISUPPORTS1(FinishTransactionRunnable, nsIRunnable)
NS_IMETHODIMP
FinishTransactionRunnable::Run()
{
NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
if (!gInstance) {
NS_ERROR("Running after shutdown!");
return NS_ERROR_FAILURE;
}
gInstance->FinishTransaction(mTransaction);
if (mFinishRunnable) {
mFinishRunnable->Run();
mFinishRunnable = nsnull;
}
return NS_OK;
}