Make Resource RefCountedWillBeGarbageCollectedFinalized, attempt #2

third_party/WebKit/Source/core/fetch/Resource.cpp

Index: third_party/WebKit/Source/core/fetch/Resource.cpp
diff --git a/third_party/WebKit/Source/core/fetch/Resource.cpp b/third_party/WebKit/Source/core/fetch/Resource.cpp
index 4f6712198a66ac12d94686ff5e7702792a46d80e..a8e26add4501e71a3baa01f1332b39d27d16e5d9 100644
--- a/third_party/WebKit/Source/core/fetch/Resource.cpp
+++ b/third_party/WebKit/Source/core/fetch/Resource.cpp
@@ -31,7 +31,6 @@
 #include "core/fetch/ResourceClientWalker.h"
 #include "core/fetch/ResourceFetcher.h"
 #include "core/fetch/ResourceLoader.h"
-#include "core/fetch/ResourcePtr.h"
 #include "core/inspector/InspectorInstrumentation.h"
 #include "platform/Logging.h"
 #include "platform/SharedBuffer.h"
@@ -155,17 +154,13 @@ Resource::Resource(const ResourceRequest& request, Type type)
     , m_identifier(0)
     , m_encodedSize(0)
     , m_decodedSize(0)
-    , m_handleCount(0)
     , m_preloadCount(0)
-    , m_protectorCount(0)
     , m_cacheIdentifier(MemoryCache::defaultCacheIdentifier())
     , m_preloadResult(PreloadNotReferenced)
     , m_requestedFromNetworkingLayer(false)
     , m_loading(false)
-    , m_switchingClientsToRevalidatedResource(false)
     , m_type(type)
     , m_status(Pending)
-    , m_wasPurged(false)
     , m_needsSynchronousCacheHit(false)
     , m_linkPreload(false)
 #ifdef ENABLE_RESOURCE_IS_DELETED_CHECK
@@ -174,7 +169,6 @@ Resource::Resource(const ResourceRequest& request, Type type)
 {
     ASSERT(m_type == unsigned(type)); // m_type is a bitfield, so this tests careless updates of the enum.
     InstanceCounters::incrementCounter(InstanceCounters::ResourceCounter);
-    memoryCache()->registerLiveResource(*this);
 
     // Currently we support the metadata caching only for HTTP family.
     if (m_resourceRequest.url().protocolIsInHTTPFamily())
@@ -191,19 +185,18 @@ Resource::Resource(const ResourceRequest& request, Type type)
 
 Resource::~Resource()
 {
-    ASSERT(canDelete());
-    RELEASE_ASSERT(!memoryCache()->contains(this));
-    RELEASE_ASSERT(!ResourceCallback::callbackHandler()->isScheduled(this));
     assertAlive();
 
 #ifdef ENABLE_RESOURCE_IS_DELETED_CHECK
     m_deleted = true;
 #endif
+
     InstanceCounters::decrementCounter(InstanceCounters::ResourceCounter);
 }
 
-void Resource::dispose()
+void Resource::removedFromMemoryCache()
 {
+    InspectorInstrumentation::removedResourceFromMemoryCache(this);
 }
 
 DEFINE_TRACE(Resource)
@@ -446,18 +439,13 @@ bool Resource::unlock()
     if (!m_data->isLocked())
         return true;
 
-    if (!memoryCache()->contains(this) || hasClients() || m_handleCount > 1 || !m_revalidatingRequest.isNull() || !m_loadFinishTime || !isSafeToUnlock())
+    if (!memoryCache()->contains(this) || hasClients() || !m_revalidatingRequest.isNull() || !m_loadFinishTime || !isSafeToUnlock())
         return false;
 
     m_data->unlock();
     return true;
 }
 
-bool Resource::hasRightHandleCountApartFromCache(unsigned targetCount) const
-{
-    return m_handleCount == targetCount + (memoryCache()->contains(this) ? 1 : 0);
-}
-
 void Resource::responseReceived(const ResourceResponse& response, PassOwnPtr<WebDataConsumerHandle>)
 {
     m_responseTimestamp = currentTime();
@@ -529,12 +517,6 @@ WeakPtrWillBeRawPtr<Resource> Resource::asWeakPtr()
 #endif
 }
 
-bool Resource::canDelete() const
-{
-    return !hasClients() && !m_loader && !m_preloadCount && hasRightHandleCountApartFromCache(0)
-        && !m_protectorCount;
-}
-
 String Resource::reasonNotDeletable() const
 {
     StringBuilder builder;
@@ -563,20 +545,6 @@ String Resource::reasonNotDeletable() const
         builder.appendNumber(m_preloadCount);
         builder.append(")");
     }
-    if (!hasRightHandleCountApartFromCache(0)) {
-        if (!builder.isEmpty())
-            builder.append(' ');
-        builder.append("m_handleCount(");
-        builder.appendNumber(m_handleCount);
-        builder.append(")");
-    }
-    if (m_protectorCount) {
-        if (!builder.isEmpty())
-            builder.append(' ');
-        builder.append("m_protectorCount(");
-        builder.appendNumber(m_protectorCount);
-        builder.append(")");
-    }
     if (memoryCache()->contains(this)) {
         if (!builder.isEmpty())
             builder.append(' ');
@@ -585,11 +553,6 @@ String Resource::reasonNotDeletable() const
     return builder.toString();
 }
 
-bool Resource::hasOneHandle() const
-{
-    return hasRightHandleCountApartFromCache(1);
-}
-
 CachedMetadata* Resource::cachedMetadata(unsigned dataTypeID) const
 {
     if (!m_cachedMetadata || m_cachedMetadata->dataTypeID() != dataTypeID)
@@ -679,11 +642,10 @@ void Resource::removeClient(ResourceClient* client)
     if (m_clientsAwaitingCallback.isEmpty())
         ResourceCallback::callbackHandler()->cancel(this);
 
-    bool deleted = deleteIfPossible();
-    if (!deleted && !hasClients()) {
+    if (!hasClients()) {
+        RefPtrWillBeRawPtr<Resource> protect(this);
         memoryCache()->makeDead(this);
-        if (!m_switchingClientsToRevalidatedResource)
-            allClientsRemoved();
+        allClientsRemoved();
 
         // RFC2616 14.9.2:
         // "no-store: ... MUST make a best-effort attempt to remove the information from volatile storage as promptly as possible"
@@ -703,7 +665,7 @@ void Resource::allClientsRemoved()
 {
     if (!m_loader)
         return;
-    if (m_type == MainResource || m_type == Raw)
+    if (m_type == MainResource || m_type == Raw || !memoryCache()->contains(this))
         cancelTimerFired(&m_cancelTimer);
     else if (!m_cancelTimer.isActive())
         m_cancelTimer.startOneShot(0, BLINK_FROM_HERE);
@@ -716,26 +678,12 @@ void Resource::cancelTimerFired(Timer<Resource>* timer)
     ASSERT_UNUSED(timer, timer == &m_cancelTimer);
     if (hasClients() || !m_loader)
         return;
-    ResourcePtr<Resource> protect(this);
+    RefPtrWillBeRawPtr<Resource> protect(this);
     m_loader->cancelIfNotFinishing();
     if (m_status != Cached)
         memoryCache()->remove(this);
 }
 
-bool Resource::deleteIfPossible()
-{
-    if (canDelete() && !memoryCache()->contains(this)) {
-        InspectorInstrumentation::willDestroyResource(this);
-        dispose();
-        memoryCache()->unregisterLiveResource(*this);
-#if !ENABLE(OILPAN)
-        delete this;
-#endif
-        return true;
-    }
-    return false;
-}
-
 void Resource::setDecodedSize(size_t decodedSize)
 {
     if (decodedSize == m_decodedSize)
@@ -807,14 +755,13 @@ void Resource::onMemoryDump(WebMemoryDumpLevelOfDetail levelOfDetail, WebProcess
     const String dumpName = getMemoryDumpName();
     WebMemoryAllocatorDump* dump = memoryDump->createMemoryAllocatorDump(dumpName);
     dump->addScalar("encoded_size", "bytes", m_encodedSize);
-    if (canDelete()) {
-        dump->addScalar("dead_size", "bytes", m_encodedSize);
-    } else {
+    if (m_data && m_data->isLocked())
         dump->addScalar("live_size", "bytes", m_encodedSize);
-    }
+    else
+        dump->addScalar("dead_size", "bytes", m_encodedSize);
 
     if (m_data) {
-        dump->addScalar("purgeable_size", "bytes", isPurgeable() && !wasPurged() ? encodedSize() + overheadSize() : 0);
+        dump->addScalar("purgeable_size", "bytes", isPurgeable() ? encodedSize() + overheadSize() : 0);
         m_data->onMemoryDump(dumpName, memoryDump);
     }
 
@@ -896,29 +843,6 @@ void Resource::revalidationFailed()
     destroyDecodedDataForFailedRevalidation();
 }
 
-void Resource::registerHandle(ResourcePtrBase* h)
-{
-    assertAlive();
-    ++m_handleCount;
-}
-
-void Resource::unregisterHandle(ResourcePtrBase* h)
-{
-    assertAlive();
-    ASSERT(m_handleCount > 0);
-    --m_handleCount;
-
-    if (!m_handleCount) {
-        if (deleteIfPossible())
-            return;
-        unlock();
-    } else if (m_handleCount == 1 && memoryCache()->contains(this)) {
-        unlock();
-        if (!hasClients())
-            memoryCache()->prune(this);
-    }
-}
-
 bool Resource::canReuseRedirectChain()
 {
     for (auto& redirect : m_redirectChain) {
@@ -960,11 +884,6 @@ bool Resource::isPurgeable() const
     return m_data && !m_data->isLocked();
 }
 
-bool Resource::wasPurged() const
-{
-    return m_wasPurged;
-}
-
 bool Resource::lock()
 {
     if (!m_data)
@@ -974,8 +893,10 @@ bool Resource::lock()
 
     ASSERT(!hasClients());
 
+    // If locking fails, our buffer has been purged. There's no point
+    // in leaving a purged resource in MemoryCache.
     if (!m_data->lock()) {
-        m_wasPurged = true;
+        memoryCache()->remove(this);
         return false;
     }
     return true;
@@ -1055,8 +976,8 @@ bool Resource::ResourceCallback::isScheduled(Resource* resource) const
 
 void Resource::ResourceCallback::runTask()
 {
-    Vector<ResourcePtr<Resource>> resources;
-    for (const RawPtrWillBeMember<Resource>& resource : m_resourcesWithPendingClients)
+    WillBeHeapVector<RefPtrWillBeMember<Resource>> resources;
+    for (const RefPtrWillBeMember<Resource>& resource : m_resourcesWithPendingClients)
         resources.append(resource.get());
     m_resourcesWithPendingClients.clear();