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third_party/WebKit/Source/platform/PurgeableVector.cpp

Index: third_party/WebKit/Source/platform/PurgeableVector.cpp
diff --git a/third_party/WebKit/Source/platform/PurgeableVector.cpp b/third_party/WebKit/Source/platform/PurgeableVector.cpp
index 01cb41f2d68ba3eb8369ba8546c29d8ccc748521..b59feb2aabbab0ab93846d86b31ceaf5f0a74b43 100644
--- a/third_party/WebKit/Source/platform/PurgeableVector.cpp
+++ b/third_party/WebKit/Source/platform/PurgeableVector.cpp
@@ -33,6 +33,7 @@
 
 #include "public/platform/Platform.h"
 #include "public/platform/WebDiscardableMemory.h"
+#include "public/platform/WebProcessMemoryDump.h"
 #include "wtf/Assertions.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
@@ -79,6 +80,17 @@ void PurgeableVector::reserveCapacity(size_t capacity)
     moveDataFromDiscardableToVector();
 }
 
+void PurgeableVector::onMemoryDump(const String& dumpName, WebProcessMemoryDump* memoryDump) const
+{
+    WebMemoryAllocatorDump* dump = memoryDump->createDiscardableMemoryAllocatorDump(dumpName, m_discardable.get());
+    if (m_discardable) {
+        dump->AddScalar("discardable_size", "bytes", m_discardableSize);

[haraken, 2015/09/28 14:54:02]

This is confusing. Even if m_discardable is non-null, it is not discardable
while m_discardable.isLocked() returns true. I think this should be:

  if (m_discardable) {
    if (m_discardable.isLocked())
      ...;
    else
      ...;
  } else {
    ...;
  }

[ssid, 2015/09/28 16:24:38]

I am sorry I screwed up the condition here. Now fixed it.

Now it just dumps both, not thinking if locked or not.
It means: if discardable it creates a discardable dump,
and it creates a normal dump with sub-allocations from partition alloc.
This createDiscardableMemoryAllocatorDump is added in the cl
http://crrev.com/1372573003.

Do you think this is fine?

+    } else if (m_vector.size() > 0) {
+        dump->AddScalar("size", "bytes", m_vector.size());
+        memoryDump->AddSuballocation(dump->guid(), String(WTF::Partitions::allocatorPoolNameForTracing()));

[haraken, 2015/09/28 14:54:02]

What does allocatorPoolNameForTracing return? (I couldn't find it in a code
search.)

[ssid, 2015/09/28 16:24:38]

Sorry, this is added in this CL https://codereview.chromium.org/1366203002/.
Just returns "partition_alloc/allocated_objects" meaning this is allocated from
partitionAlloc.

+    }
+}
+
 void PurgeableVector::moveDataFromDiscardableToVector()
 {
     if (m_discardable) {