NOCOMMIT: Rebased https://codereview.chromium.org/2696503004 on service rename

base/trace_event/memory_dump_manager.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/trace_event/memory_dump_manager.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "base/allocator/features.h"
@@ skipping 134 matching lines @@
   return Singleton<MemoryDumpManager,
                    LeakySingletonTraits<MemoryDumpManager>>::get();
 }
 
 // static
 void MemoryDumpManager::SetInstanceForTesting(MemoryDumpManager* instance) {
   g_instance_for_testing = instance;
 }
 
 MemoryDumpManager::MemoryDumpManager()
-    : delegate_(nullptr),
-      is_coordinator_(false),
-      memory_tracing_enabled_(0),
+    : memory_tracing_enabled_(0),
       tracing_process_id_(kInvalidTracingProcessId),
       dumper_registrations_ignored_for_testing_(false),
       heap_profiling_enabled_(false) {
   g_next_guid.GetNext();  // Make sure that first guid is not zero.
 
   // At this point the command line may not be initialized but we try to
   // enable the heap profiler to capture allocations as soon as possible.
   EnableHeapProfilingIfNeeded();
 
   strict_thread_check_blacklist_.insert(std::begin(kStrictThreadCheckBlacklist),
@@ skipping 34 matching lines @@
   } else {
     CHECK(false) << "Invalid mode '" << profiling_mode << "' for "
                << switches::kEnableHeapProfiling << " flag.";
   }
 
   for (auto mdp : dump_providers_)
     mdp->dump_provider->OnHeapProfilingEnabled(true);
   heap_profiling_enabled_ = true;
 }
 
-void MemoryDumpManager::Initialize(MemoryDumpManagerDelegate* delegate,
-                                   bool is_coordinator) {
+void MemoryDumpManager::Initialize(
+    std::unique_ptr<MemoryDumpManagerDelegate> delegate) {
   {
     AutoLock lock(lock_);
     DCHECK(delegate);
     DCHECK(!delegate_);
-    delegate_ = delegate;
-    is_coordinator_ = is_coordinator;
+    delegate_.swap(delegate);
     EnableHeapProfilingIfNeeded();
   }
 
 // Enable the core dump providers.
 #if defined(MALLOC_MEMORY_TRACING_SUPPORTED)
   RegisterDumpProvider(MallocDumpProvider::GetInstance(), "Malloc", nullptr);
 #endif
 
 #if defined(OS_ANDROID)
   RegisterDumpProvider(JavaHeapDumpProvider::GetInstance(), "JavaHeap",
@@ skipping 210 matching lines @@
   const uint64_t guid =
       TraceLog::GetInstance()->MangleEventId(g_next_guid.GetNext());
 
   // Creates an async event to keep track of the global dump evolution.
   // The |wrapped_callback| will generate the ASYNC_END event and then invoke
   // the real |callback| provided by the caller.
   TRACE_EVENT_NESTABLE_ASYNC_BEGIN0(kTraceCategory, "GlobalMemoryDump",
                                     TRACE_ID_MANGLE(guid));
   MemoryDumpCallback wrapped_callback = Bind(&OnGlobalDumpDone, callback);
 
-  // Technically there is no need to grab the |lock_| here as the delegate is
-  // long-lived and can only be set by Initialize(), which is locked and
-  // necessarily happens before memory_tracing_enabled_ == true.
-  // Not taking the |lock_|, though, is lakely make TSan barf and, at this point
-  // (memory-infra is enabled) we're not in the fast-path anymore.
-  MemoryDumpManagerDelegate* delegate;
-  {
-    AutoLock lock(lock_);
-    delegate = delegate_;
-  }
-
   // The delegate will coordinate the IPC broadcast and at some point invoke
   // CreateProcessDump() to get a dump for the current process.
   MemoryDumpRequestArgs args = {guid, dump_type, level_of_detail};
-  delegate->RequestGlobalMemoryDump(args, wrapped_callback);
+  delegate_->RequestGlobalMemoryDump(args, wrapped_callback);
 }
 
 void MemoryDumpManager::RequestGlobalDump(
     MemoryDumpType dump_type,
     MemoryDumpLevelOfDetail level_of_detail) {
   RequestGlobalDump(dump_type, level_of_detail, MemoryDumpCallback());
 }
 
 void MemoryDumpManager::CreateProcessDump(const MemoryDumpRequestArgs& args,
                                           const MemoryDumpCallback& callback) {
@@ skipping 325 matching lines @@
     dump_thread_ = std::move(dump_thread);
 
     dump_providers_for_polling_.clear();
     for (const auto& mdpinfo : dump_providers_) {
       if (mdpinfo->options.is_fast_polling_supported)
         dump_providers_for_polling_.insert(mdpinfo);
     }
 
     subtle::NoBarrier_Store(&memory_tracing_enabled_, 1);
 
-    if (!is_coordinator_)
+    if (!delegate_->IsCoordinator())
       return;
   }
 
   // Enable periodic dumps if necessary.
   periodic_dump_timer_.Start(trace_config.memory_dump_config().triggers);
 }
 
 void MemoryDumpManager::OnTraceLogDisabled() {
   // There might be a memory dump in progress while this happens. Therefore,
   // ensure that the MDM state which depends on the tracing enabled / disabled
@@ skipping 165 matching lines @@
   if (heavy_dump_rate_ > 0 && periodic_dumps_count_ % heavy_dump_rate_ == 0)
     level_of_detail = MemoryDumpLevelOfDetail::DETAILED;
   ++periodic_dumps_count_;
 
   MemoryDumpManager::GetInstance()->RequestGlobalDump(
       MemoryDumpType::PERIODIC_INTERVAL, level_of_detail);
 }
 
 }  // namespace trace_event
 }  // namespace base