Disabled MallocHooks code in Release due to performance concerns. Added enable_malloc_hooks flag to…

runtime/vm/malloc_hooks.cc

Index: runtime/vm/malloc_hooks.cc
diff --git a/runtime/vm/malloc_hooks.cc b/runtime/vm/malloc_hooks.cc
index 08a053a81d19b0b32f277a71a89a9095e50dce7d..64e889270dc850c6b8c602a7fd1409ba020e8e29 100644
--- a/runtime/vm/malloc_hooks.cc
+++ b/runtime/vm/malloc_hooks.cc
@@ -203,52 +203,64 @@ AddressMap* MallocHooksState::address_map_ = NULL;
 
 
 void MallocHooks::InitOnce() {
-  MutexLocker ml(MallocHooksState::malloc_hook_mutex());
-  ASSERT(!MallocHooksState::Active());
+  if (FLAG_enable_malloc_hooks) {

[zra, 2017/02/17 23:43:27]

if (!FLAG_enable_malloc_hooks) {
  return;
}

[bkonyi, 2017/02/18 00:01:11]

Done.

+    MutexLocker ml(MallocHooksState::malloc_hook_mutex());
+    ASSERT(!MallocHooksState::Active());
 
-  MallocHookScope::InitMallocHookFlag();
-  MallocHooksState::Init();
+    MallocHookScope::InitMallocHookFlag();
+    MallocHooksState::Init();
 
-  // Register malloc hooks.
-  bool success = false;
-  success = MallocHook::AddNewHook(&MallocHooksState::RecordAllocHook);
-  ASSERT(success);
-  success = MallocHook::AddDeleteHook(&MallocHooksState::RecordFreeHook);
-  ASSERT(success);
+    // Register malloc hooks.
+    bool success = false;
+    success = MallocHook::AddNewHook(&MallocHooksState::RecordAllocHook);
+    ASSERT(success);
+    success = MallocHook::AddDeleteHook(&MallocHooksState::RecordFreeHook);
+    ASSERT(success);
+  }
 }
 
 
 void MallocHooks::TearDown() {
-  MutexLocker ml(MallocHooksState::malloc_hook_mutex());
-  ASSERT(MallocHooksState::Active());
+  if (FLAG_enable_malloc_hooks) {

[zra, 2017/02/17 23:43:27]

ditto

[bkonyi, 2017/02/18 00:01:11]

Done.

+    MutexLocker ml(MallocHooksState::malloc_hook_mutex());
+    ASSERT(MallocHooksState::Active());
 
-  // Remove malloc hooks.
-  bool success = false;
-  success = MallocHook::RemoveNewHook(&MallocHooksState::RecordAllocHook);
-  ASSERT(success);
-  success = MallocHook::RemoveDeleteHook(&MallocHooksState::RecordFreeHook);
-  ASSERT(success);
+    // Remove malloc hooks.
+    bool success = false;
+    success = MallocHook::RemoveNewHook(&MallocHooksState::RecordAllocHook);
+    ASSERT(success);
+    success = MallocHook::RemoveDeleteHook(&MallocHooksState::RecordFreeHook);
+    ASSERT(success);
 
-  MallocHooksState::TearDown();
-  MallocHookScope::DestroyMallocHookFlag();
+    MallocHooksState::TearDown();
+    MallocHookScope::DestroyMallocHookFlag();
+  }
 }
 
 
 void MallocHooks::ResetStats() {
-  MutexLocker ml(MallocHooksState::malloc_hook_mutex());
-  if (MallocHooksState::Active()) {
-    MallocHooksState::ResetStats();
+  if (FLAG_enable_malloc_hooks) {

[zra, 2017/02/17 23:43:27]

ditto

[bkonyi, 2017/02/18 00:01:11]

Done.

+    MutexLocker ml(MallocHooksState::malloc_hook_mutex());
+    if (MallocHooksState::Active()) {
+      MallocHooksState::ResetStats();
+    }
   }
 }
 
 
 bool MallocHooks::Active() {
+  if (!FLAG_enable_malloc_hooks) {
+    return false;
+  }
   ASSERT(MallocHooksState::malloc_hook_mutex()->IsOwnedByCurrentThread());
   return MallocHooksState::Active();
 }
 
 
 void MallocHooks::PrintToJSONObject(JSONObject* jsobj) {
+  if (!FLAG_enable_malloc_hooks) {
+    return;
+  }
   intptr_t allocated_memory = 0;
   intptr_t allocation_count = 0;
   bool add_usage = false;
@@ -271,12 +283,18 @@ void MallocHooks::PrintToJSONObject(JSONObject* jsobj) {
 
 
 intptr_t MallocHooks::allocation_count() {
+  if (!FLAG_enable_malloc_hooks) {
+    return 0;
+  }
   MutexLocker ml(MallocHooksState::malloc_hook_mutex());
   return MallocHooksState::allocation_count();
 }
 
 
 intptr_t MallocHooks::heap_allocated_memory_in_bytes() {
+  if (!FLAG_enable_malloc_hooks) {
+    return 0;
+  }
   MutexLocker ml(MallocHooksState::malloc_hook_mutex());
   return MallocHooksState::heap_allocated_memory_in_bytes();
 }