Table blob leakage tracking

third_party/WebKit/Source/platform/fonts/shaping/HarfBuzzFace.cpp

Index: third_party/WebKit/Source/platform/fonts/shaping/HarfBuzzFace.cpp
diff --git a/third_party/WebKit/Source/platform/fonts/shaping/HarfBuzzFace.cpp b/third_party/WebKit/Source/platform/fonts/shaping/HarfBuzzFace.cpp
index 46d7870da57e8e3449392839be5bff982546d014..c3065145a386209970ccc690b91a7df3100a3d92 100644
--- a/third_party/WebKit/Source/platform/fonts/shaping/HarfBuzzFace.cpp
+++ b/third_party/WebKit/Source/platform/fonts/shaping/HarfBuzzFace.cpp
@@ -267,6 +267,56 @@ static hb_font_funcs_t* harfBuzzSkiaGetFontFuncs()
     return harfBuzzSkiaFontFuncs;
 }
 
+
+struct HbAllocMeta {
+    unsigned int tableSize;
+    hb_tag_t tableTag;
+};
+
+typedef HashMap<hb_tag_t, unsigned int, WTF::IntHash<hb_tag_t>, WTF::UnsignedWithZeroKeyHashTraits<hb_tag_t>> TagTracking;
+
+TagTracking* tagTracker() {
+    DEFINE_STATIC_LOCAL(TagTracking, s_TagTracking, ());
+    return &s_TagTracking;
+}
+
+void reportTagTracking() {
+    LOG(INFO) << "\n";
+    char tagBuf[4] = { 0 };
+    unsigned int totalLeftover = 0;
+    for (auto tagTrackIterator = tagTracker()->begin(); tagTrackIterator != tagTracker()->end(); ++tagTrackIterator) {
+        hb_tag_to_string(tagTrackIterator->key, tagBuf);
+        LOG(INFO) << "Tag: " << tagBuf << " leftover kb " << tagTrackIterator->value / 1024.0;
+        totalLeftover += tagTrackIterator->value;
+    }
+    LOG(INFO) << "---------------------";
+    LOG(INFO) << "Total: kb " << totalLeftover / 1024.0 << "\n";
+}
+
+void subtractFromTagTracking(hb_tag_t tag, unsigned size) {
+    auto findResult = tagTracker()->find(tag);
+    ASSERT(findResult != tagTracker()->end());
+    findResult->value -= size;
+}
+
+void tableBlobfastFree(void* p) {
+    if (p) {
+        HbAllocMeta* allocMeta = reinterpret_cast<HbAllocMeta*>(p);
+        subtractFromTagTracking(allocMeta->tableTag, allocMeta->tableSize);
+    }
+    WTF::Partitions::fastFree(p);
+    reportTagTracking();
+}
+
+void addToTagTracking(hb_tag_t tag, unsigned size) {
+    unsigned newSize = size;
+    auto tagTrackerFindResult = tagTracker()->find(tag);
+    if (tagTrackerFindResult != tagTracker()->end()) {
+        newSize += tagTrackerFindResult->value;
+    }
+    auto tagEntry = tagTracker()->set(tag, newSize);
+}
+
 #if !OS(MACOSX)
 static hb_blob_t* harfBuzzSkiaGetTable(hb_face_t* face, hb_tag_t tag, void* userData)
 {
@@ -277,15 +327,24 @@ static hb_blob_t* harfBuzzSkiaGetTable(hb_face_t* face, hb_tag_t tag, void* user
         return nullptr;
     }
 
-    char* buffer = reinterpret_cast<char*>(WTF::Partitions::fastMalloc(tableSize, WTF_HEAP_PROFILER_TYPE_NAME(HarfBuzzFontData)));
+    char* buffer = reinterpret_cast<char*>(WTF::Partitions::fastMalloc(tableSize + sizeof(HbAllocMeta), WTF_HEAP_PROFILER_TYPE_NAME(HarfBuzzFontData)));
     if (!buffer)
         return nullptr;
-    size_t actualSize = typeface->getTableData(tag, 0, tableSize, buffer);
+    size_t actualSize = typeface->getTableData(tag, 0, tableSize, buffer + sizeof(HbAllocMeta));
     if (tableSize != actualSize) {
         WTF::Partitions::fastFree(buffer);
         return nullptr;
     }
-    return hb_blob_create(const_cast<char*>(buffer), tableSize, HB_MEMORY_MODE_WRITABLE, buffer, WTF::Partitions::fastFree);
+
+    HbAllocMeta* allocMeta = reinterpret_cast<HbAllocMeta*>(buffer);
+    allocMeta->tableSize = tableSize;
+    allocMeta->tableTag = tag;
+    addToTagTracking(tag, tableSize);
+
+    hb_blob_t* returnBlob = hb_blob_create(const_cast<char*>(buffer  + sizeof(HbAllocMeta)), tableSize, HB_MEMORY_MODE_WRITABLE, buffer, tableBlobfastFree);
+    LOG(INFO) << "Blob memory allocated: " << tableSize << " bytes.";
+    ASSERT(hb_blob_get_length(returnBlob) == tableSize);
+    return returnBlob;
 }
 #endif