Bug 1685677 - Don't unnecessarily materialize a flattened array of OriginInfo*. r=dom-workers-and-storage-reviewers,janv

Differential Revision: https://phabricator.services.mozilla.com/D101151

dom/quota/ActorsParent.cpp

@@ -7,6 +7,7 @@
 #include "ActorsParent.h"
 
 // Local includes
+#include "Flatten.h"
 #include "InitializationTypes.h"
 #include "OriginScope.h"
 #include "QuotaCommon.h"
@@ -7115,11 +7116,11 @@ QuotaManager::CollectLRUOriginInfosUntil(Collect&& aCollect, Pred&& aPred) {
   return originInfos;
 }
 
-QuotaManager::OriginInfosFlatTraversable
+QuotaManager::OriginInfosNestedTraversable
 QuotaManager::LockedGetOriginInfosExceedingGroupLimit() const {
   mQuotaMutex.AssertCurrentThreadOwns();
 
-  OriginInfosFlatTraversable originInfos;
+  OriginInfosNestedTraversable originInfos;
 
   for (const auto& entry : mGroupInfoPairs) {
     const auto& pair = entry.GetData();
@@ -7146,9 +7147,7 @@ QuotaManager::LockedGetOriginInfosExceedingGroupLimit() const {
       MOZ_ASSERT(quotaManager, "Shouldn't be null!");
 
       if (groupUsage > quotaManager->GetGroupLimit()) {
-        // XXX Instead of appending into a flat array, return an array of
-        // arrays.
-        originInfos.AppendElements(CollectLRUOriginInfosUntil(
+        originInfos.AppendElement(CollectLRUOriginInfosUntil(
             [&temporaryGroupInfo, &defaultGroupInfo](auto inserter) {
               MaybeInsertOriginInfos(std::move(inserter), temporaryGroupInfo,
                                      defaultGroupInfo,
@@ -7170,7 +7169,7 @@ QuotaManager::LockedGetOriginInfosExceedingGroupLimit() const {
 
 QuotaManager::OriginInfosFlatTraversable
 QuotaManager::LockedGetOriginInfosExceedingGlobalLimit(
-    const OriginInfosFlatTraversable& aAlreadyDoomedOriginInfos,
+    const OriginInfosNestedTraversable& aAlreadyDoomedOriginInfos,
     const uint64_t aAlreadyDoomedUsage) const {
   mQuotaMutex.AssertCurrentThreadOwns();
 
@@ -7186,7 +7185,13 @@ QuotaManager::LockedGetOriginInfosExceedingGlobalLimit(
               inserter, pair->LockedGetGroupInfo(PERSISTENCE_TYPE_TEMPORARY),
               pair->LockedGetGroupInfo(PERSISTENCE_TYPE_DEFAULT),
               [&aAlreadyDoomedOriginInfos](const auto& originInfo) {
-                return !aAlreadyDoomedOriginInfos.Contains(originInfo) &&
+                return !std::any_of(aAlreadyDoomedOriginInfos.cbegin(),
+                                    aAlreadyDoomedOriginInfos.cend(),
+                                    // XXX This should capture originInfo by
+                                    // value, but it can't due to Bug 1421435.
+                                    [&originInfo](const auto& array) {
+                                      return array.Contains(originInfo);
+                                    }) &&
                        !originInfo->LockedPersisted();
               });
         }
@@ -7203,24 +7208,28 @@ QuotaManager::LockedGetOriginInfosExceedingGlobalLimit(
       });
 }
 
-QuotaManager::OriginInfosFlatTraversable
+QuotaManager::OriginInfosNestedTraversable
 QuotaManager::GetOriginInfosExceedingLimits() const {
   MutexAutoLock lock(mQuotaMutex);
 
   auto originInfos = LockedGetOriginInfosExceedingGroupLimit();
 
-  const uint64_t doomedUsage =
-      std::accumulate(originInfos.cbegin(), originInfos.cend(), uint64_t(0),
-                      [](uint64_t oldValue, const auto& originInfo) {
-                        return oldValue + originInfo->LockedUsage();
-                      });
+  const uint64_t doomedUsage = std::accumulate(
+      originInfos.cbegin(), originInfos.cend(), uint64_t(0),
+      [](uint64_t oldValue, const auto& currentOriginInfos) {
+        return std::accumulate(currentOriginInfos.cbegin(),
+                               currentOriginInfos.cend(), oldValue,
+                               [](uint64_t oldValue, const auto& originInfo) {
+                                 return oldValue + originInfo->LockedUsage();
+                               });
+      });
 
   // Evicting origins that exceed their group limit also affects the global
   // temporary storage usage. If the global temporary storage limit would still
   // be exceeded after evicting the origins that were already selected, we need
   // to specifically evict origins to get below the global limit.
   if (mTemporaryStorageUsage - doomedUsage > mTemporaryStorageLimit) {
-    originInfos.AppendElements(
+    originInfos.AppendElement(
         LockedGetOriginInfosExceedingGlobalLimit(originInfos, doomedUsage));
   }
 
@@ -7228,13 +7237,12 @@ QuotaManager::GetOriginInfosExceedingLimits() const {
 }
 
 void QuotaManager::ClearOrigins(
-    const OriginInfosFlatTraversable& aDoomedOriginInfos) {
+    const OriginInfosNestedTraversable& aDoomedOriginInfos) {
   AssertIsOnIOThread();
 
   // XXX Does this need to be done a) in order and/or b) sequentially?
-  // XXX We don't need to concatenate the results of the two steps. It would be
-  // sufficient to chain the ranges for iteration.
-  for (const auto& doomedOriginInfo : aDoomedOriginInfos) {
+  for (const auto& doomedOriginInfo :
+       Flatten<OriginInfosFlatTraversable::elem_type>(aDoomedOriginInfos)) {
 #ifdef DEBUG
     {
       MutexAutoLock lock(mQuotaMutex);
@@ -7249,14 +7257,16 @@ void QuotaManager::ClearOrigins(
   {
     MutexAutoLock lock(mQuotaMutex);
 
-    for (const auto& doomedOriginInfo : aDoomedOriginInfos) {
+    for (const auto& doomedOriginInfo :
+         Flatten<OriginInfosFlatTraversable::elem_type>(aDoomedOriginInfos)) {
       LockedRemoveQuotaForOrigin(
           doomedOriginInfo->mGroupInfo->mPersistenceType,
           {doomedOriginInfo->mGroupInfo->mGroup, doomedOriginInfo->mOrigin});
     }
   }
 
-  for (const auto& doomedOriginInfo : aDoomedOriginInfos) {
+  for (const auto& doomedOriginInfo :
+       Flatten<OriginInfosFlatTraversable::elem_type>(aDoomedOriginInfos)) {
     OriginClearCompleted(doomedOriginInfo->mGroupInfo->mPersistenceType,
                          doomedOriginInfo->mOrigin, Nullable<Client::Type>());
   }

dom/quota/Flatten.h

@@ -0,0 +1,109 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef DOM_QUOTA_FLATTEN_H_
+#define DOM_QUOTA_FLATTEN_H_
+
+#include <iterator>
+#include <type_traits>
+#include <utility>
+
+// XXX This should be moved to MFBT.
+
+namespace mozilla::dom::quota {
+
+namespace detail {
+
+using std::begin;
+using std::end;
+
+template <typename T, typename NestedRange>
+auto Flatten(const NestedRange& aRange) -> std::enable_if_t<
+    std::is_same_v<T, typename decltype(begin(
+                          std::declval<const NestedRange&>()))::value_type>,
+    const NestedRange&> {
+  return aRange;
+}
+
+template <typename T, typename NestedRange>
+struct FlatIter {
+  using OuterIterator = decltype(begin(std::declval<const NestedRange&>()));
+  using InnerIterator =
+      decltype(begin(*begin(std::declval<const NestedRange&>())));
+
+  explicit FlatIter(const NestedRange& aRange, OuterIterator aIter)
+      : mOuterIter{std::move(aIter)}, mOuterEnd{end(aRange)} {
+    InitInner();
+  }
+
+  const T& operator*() const { return *mInnerIter; }
+
+  FlatIter& operator++() {
+    if (mInnerIter != mInnerEnd) {
+      ++mInnerIter;
+    } else {
+      ++mOuterIter;
+      InitInner();
+    }
+    return *this;
+  }
+
+  bool operator!=(const FlatIter& aOther) const {
+    return mOuterIter != aOther.mOuterIter || mInnerIter != aOther.mInnerIter;
+  }
+
+ private:
+  void InitInner() {
+    if (mOuterIter != mOuterEnd) {
+      const auto& innerRange = *mOuterIter;
+
+      mInnerIter = begin(innerRange);
+      mInnerEnd = end(innerRange);
+    }
+  }
+
+  OuterIterator mOuterIter;
+  const OuterIterator mOuterEnd;
+
+  InnerIterator mInnerIter;
+  InnerIterator mInnerEnd;
+};
+
+template <typename T, typename NestedRange>
+struct FlatRange {
+  explicit FlatRange(const NestedRange& aRange) : mRange{aRange} {}
+
+  auto begin() const {
+    using std::begin;
+    return FlatIter<T, NestedRange>{mRange, begin(mRange)};
+  }
+  auto end() const {
+    using std::end;
+    return FlatIter<T, NestedRange>{mRange, end(mRange)};
+  }
+
+ private:
+  const NestedRange& mRange;
+};
+
+template <typename T, typename NestedRange>
+auto Flatten(const NestedRange& aRange) -> std::enable_if_t<
+    !std::is_same_v<T, typename decltype(begin(
+                           std::declval<const NestedRange&>()))::value_type>,
+    FlatRange<T, NestedRange>> {
+  return FlatRange<T, NestedRange>{aRange};
+}
+
+}  // namespace detail
+
+template <typename T, typename NestedRange>
+auto Flatten(const NestedRange& aRange) {
+  return detail::Flatten<T>(aRange);
+}
+
+}  // namespace mozilla::dom::quota
+
+#endif

dom/quota/QuotaManager.h

@@ -563,15 +563,18 @@ class QuotaManager final : public BackgroundThreadObject {
   using OriginInfosFlatTraversable =
       nsTArray<NotNull<RefPtr<const OriginInfo>>>;
 
-  OriginInfosFlatTraversable LockedGetOriginInfosExceedingGroupLimit() const;
+  using OriginInfosNestedTraversable =
+      nsTArray<nsTArray<NotNull<RefPtr<const OriginInfo>>>>;
+
+  OriginInfosNestedTraversable LockedGetOriginInfosExceedingGroupLimit() const;
 
   OriginInfosFlatTraversable LockedGetOriginInfosExceedingGlobalLimit(
-      const OriginInfosFlatTraversable& aAlreadyDoomedOriginInfos,
+      const OriginInfosNestedTraversable& aAlreadyDoomedOriginInfos,
       uint64_t aAlreadyDoomedUsage) const;
 
-  OriginInfosFlatTraversable GetOriginInfosExceedingLimits() const;
+  OriginInfosNestedTraversable GetOriginInfosExceedingLimits() const;
 
-  void ClearOrigins(const OriginInfosFlatTraversable& aDoomedOriginInfos);
+  void ClearOrigins(const OriginInfosNestedTraversable& aDoomedOriginInfos);
 
   void CleanupTemporaryStorage();