Enable sharding of AllocationRegister on desktop.

base/trace_event/malloc_dump_provider.cc

Index: base/trace_event/malloc_dump_provider.cc
diff --git a/base/trace_event/malloc_dump_provider.cc b/base/trace_event/malloc_dump_provider.cc
index 7b3831c08d64a723d3773ba754708a3121c69e49..0e37293eac0894b84c59e8a0bba07ac487f6df89 100644
--- a/base/trace_event/malloc_dump_provider.cc
+++ b/base/trace_event/malloc_dump_provider.cc
@@ -14,9 +14,9 @@
 #include "base/debug/profiler.h"
 #include "base/trace_event/heap_profiler_allocation_context.h"
 #include "base/trace_event/heap_profiler_allocation_context_tracker.h"
-#include "base/trace_event/heap_profiler_allocation_register.h"
 #include "base/trace_event/heap_profiler_heap_dump_writer.h"
 #include "base/trace_event/process_memory_dump.h"
+#include "base/trace_event/sharded_allocation_register.h"
 #include "base/trace_event/trace_event_argument.h"
 #include "build/build_config.h"
 
@@ -190,7 +190,8 @@ MallocDumpProvider* MallocDumpProvider::GetInstance() {
 }
 
 MallocDumpProvider::MallocDumpProvider()
-    : heap_profiler_enabled_(false), tid_dumping_heap_(kInvalidThreadId) {}
+    : allocation_register_(new ShardedAllocationRegister),
+      tid_dumping_heap_(kInvalidThreadId) {}
 
 MallocDumpProvider::~MallocDumpProvider() {}
 
@@ -286,7 +287,7 @@ bool MallocDumpProvider::OnMemoryDump(const MemoryDumpArgs& args,
   }
 
   // Heap profiler dumps.
-  if (!heap_profiler_enabled_)
+  if (!allocation_register_->IsEnabled())
     return true;
 
   // The dumps of the heap profiler should be created only when heap profiling
@@ -304,18 +305,14 @@ bool MallocDumpProvider::OnMemoryDump(const MemoryDumpArgs& args,
     TraceEventMemoryOverhead overhead;
     std::unordered_map<AllocationContext, AllocationMetrics> metrics_by_context;
     {

[Primiano Tucci (use gerrit), 2017/05/22 16:37:50]

at this point this {} scope delimiter is not needed anymore.

[erikchen, 2017/05/22 17:10:42]

Done.

-      AutoLock lock(allocation_register_lock_);
       if (allocation_register_) {

[Primiano Tucci (use gerrit), 2017/05/22 16:37:50]

this condition is always going to evaluate to true, as you populate the
unique_ptr on ctor. I guess you want a if(...IsEnabled()) ?

[erikchen, 2017/05/22 17:10:42]

The condition ins already checked on line 290. Removed this line.

         if (args.level_of_detail == MemoryDumpLevelOfDetail::DETAILED) {
-          for (const auto& alloc_size : *allocation_register_) {
-            AllocationMetrics& metrics = metrics_by_context[alloc_size.context];
-            metrics.size += alloc_size.size;
-            metrics.count++;
-
-            // Aggregate data for objects allocated through the shim.
-            shim_allocated_objects_size += alloc_size.size;
-            shim_allocated_objects_count++;
-          }
+          ShardedAllocationRegister::OutputMetrics metrics =
+              allocation_register_->UpdateAndReturnsMetrics(metrics_by_context);
+
+          // Aggregate data for objects allocated through the shim.
+          shim_allocated_objects_size += metrics.size;
+          shim_allocated_objects_count += metrics.count;
         }
         allocation_register_->EstimateTraceMemoryOverhead(&overhead);
       }
@@ -326,7 +323,7 @@ bool MallocDumpProvider::OnMemoryDump(const MemoryDumpArgs& args,
       inner_dump->AddScalar("shim_allocator_object_count",
                              MemoryAllocatorDump::kUnitsObjects,
                              shim_allocated_objects_count);
-    }  // lock(allocation_register_lock_)
+    }
     pmd->DumpHeapUsage(metrics_by_context, overhead, "malloc");
   }
   tid_dumping_heap_ = kInvalidThreadId;
@@ -337,20 +334,15 @@ bool MallocDumpProvider::OnMemoryDump(const MemoryDumpArgs& args,
 void MallocDumpProvider::OnHeapProfilingEnabled(bool enabled) {
 #if BUILDFLAG(USE_EXPERIMENTAL_ALLOCATOR_SHIM)
   if (enabled) {
-    {
-      AutoLock lock(allocation_register_lock_);
-      allocation_register_.reset(new AllocationRegister());
-    }
+    if (!allocation_register_->IsInitialized())

[Primiano Tucci (use gerrit), 2017/05/22 16:37:50]

just call Initialize and early out in its implementation if IsInitialized
already?

[erikchen, 2017/05/22 17:10:42]

Done.

+      allocation_register_->Initialize();
     allocator::InsertAllocatorDispatch(&g_allocator_hooks);
   } else {
-    AutoLock lock(allocation_register_lock_);
-    allocation_register_.reset();
-    // Insert/RemoveAllocation below will no-op if the register is torn down.
-    // Once disabled, heap profiling will not re-enabled anymore for the
-    // lifetime of the process.
+    // Once we enable heap profiling, we never remove the structures from
+    // memory.
   }
 #endif
-  heap_profiler_enabled_ = enabled;
+  allocation_register_->SetEnabled(enabled);
 }
 
 void MallocDumpProvider::InsertAllocation(void* address, size_t size) {
@@ -372,8 +364,7 @@ void MallocDumpProvider::InsertAllocation(void* address, size_t size) {
   if (!tracker->GetContextSnapshot(&context))
     return;
 
-  AutoLock lock(allocation_register_lock_);
-  if (!allocation_register_)
+  if (!allocation_register_->IsEnabled())
     return;
 
   allocation_register_->Insert(address, size, context);
@@ -385,8 +376,7 @@ void MallocDumpProvider::RemoveAllocation(void* address) {
   if (tid_dumping_heap_ != kInvalidThreadId &&
       tid_dumping_heap_ == PlatformThread::CurrentId())
     return;
-  AutoLock lock(allocation_register_lock_);
-  if (!allocation_register_)
+  if (!allocation_register_->IsEnabled())
     return;
   allocation_register_->Remove(address);
 }