[tracing] Add SkResourceCache as suballocation to avoid double counting.

skia/ext/skia_memory_dump_provider.cc

Index: skia/ext/skia_memory_dump_provider.cc
diff --git a/skia/ext/skia_memory_dump_provider.cc b/skia/ext/skia_memory_dump_provider.cc
index a7c445fd5d4f1f9b34865ac3162a3b7bf0a1688e..aeb66846c387ff16cb9647a9db01965288176472 100644
--- a/skia/ext/skia_memory_dump_provider.cc
+++ b/skia/ext/skia_memory_dump_provider.cc
@@ -4,6 +4,8 @@
 
 #include "skia_memory_dump_provider.h"
 
+#include "base/memory/discardable_shared_memory.h"
+#include "base/trace_event/malloc_dump_provider.h"
 #include "base/trace_event/memory_allocator_dump.h"
 #include "base/trace_event/memory_dump_manager.h"
 #include "base/trace_event/process_memory_dump.h"
@@ -26,16 +28,24 @@ bool SkiaMemoryDumpProvider::OnMemoryDump(
     base::trace_event::ProcessMemoryDump* process_memory_dump) {
   auto font_mad =
       process_memory_dump->CreateAllocatorDump("skia/sk_font_cache");
-  font_mad->AddScalar("size", "bytes", SkGraphics::GetFontCacheUsed());
-  font_mad->AddScalar("count", "objects", SkGraphics::GetFontCacheCountUsed());
-
+  font_mad->AddScalar(base::trace_event::MemoryAllocatorDump::kNameSize,
+                      base::trace_event::MemoryAllocatorDump::kUnitsBytes,
+                      SkGraphics::GetFontCacheUsed());
+  font_mad->AddScalar(base::trace_event::MemoryAllocatorDump::kNameObjectsCount,
+                      base::trace_event::MemoryAllocatorDump::kUnitsObjects,
+                      SkGraphics::GetFontCacheCountUsed());
+
+  const size_t skia_resource_cache_size = SkResourceCache::GetTotalBytesUsed();
   auto resource_mad =
       process_memory_dump->CreateAllocatorDump("skia/sk_resource_cache");
-  resource_mad->AddScalar("size", "bytes",
-                          SkResourceCache::GetTotalBytesUsed());
-  // TODO(ssid): crbug.com/503168. Add sub-allocation edges from discardable or
-  // malloc memory dumps to avoid double counting.
-
+  resource_mad->AddScalar(base::trace_event::MemoryAllocatorDump::kNameSize,
+                          base::trace_event::MemoryAllocatorDump::kUnitsBytes,
+                          skia_resource_cache_size);
+  const char* source_name =
+      SkResourceCache::GetDiscardableFactory()
+          ? base::DiscardableSharedMemory::kAllocatedObjectsDumpName

[petrcermak, 2015/07/29 16:39:00]

Maybe rename the constant to "kAllocatedObjects" to be consistent with
MallocDumpProvider?

[ssid, 2015/07/29 16:57:37]

Added dumpName since This is not really a dumpProvider. Just a string name
AllocatedObjects won't really mean anything to this class.

+          : base::trace_event::MallocDumpProvider::kAllocatedObjects;
+  process_memory_dump->AddSuballocation(resource_mad->guid(), source_name);
   return true;

[petrcermak, 2015/07/29 16:38:59]

nit: I'd keep a blank line in front of the return statement.

[ssid, 2015/07/29 16:57:37]

Done.

 }