chrome/profiling/memlog_connection_manager.h

// Copyright 2017 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.

#ifndef CHROME_PROFILING_MEMLOG_CONNECTION_MANAGER_H_
#define CHROME_PROFILING_MEMLOG_CONNECTION_MANAGER_H_

#include <string>
#include <vector>

#include "base/containers/flat_map.h"
#include "base/files/file.h"
#include "base/files/platform_file.h"
#include "base/macros.h"
#include "base/memory/weak_ptr.h"
#include "base/process/process_handle.h"
#include "base/synchronization/lock.h"
#include "base/values.h"
#include "build/build_config.h"
#include "chrome/common/profiling/memlog.mojom.h"
#include "chrome/profiling/backtrace_storage.h"
#include "services/resource_coordinator/public/interfaces/memory_instrumentation/memory_instrumentation.mojom.h"

namespace base {

class SequencedTaskRunner;

}  // namespace base

namespace profiling {

// Manages all connections and logging for each process. Pipes are supplied by
// the pipe server and this class will connect them to a parser and logger.
//
// Note |backtrace_storage| must outlive MemlogConnectionManager.
//
// This object is constructed on the UI thread, but the rest of the usage
// (including deletion) is on the IO thread.
class MemlogConnectionManager {
 public:
  MemlogConnectionManager();
  ~MemlogConnectionManager();

  // Parameters to DumpProcess().
  struct DumpProcessArgs {
    DumpProcessArgs();
    ~DumpProcessArgs();
    DumpProcessArgs(DumpProcessArgs&&);
    base::ProcessId pid;
    std::unique_ptr<base::DictionaryValue> metadata;
    std::vector<memory_instrumentation::mojom::VmRegionPtr> maps;
    base::File file;
    mojom::Memlog::DumpProcessCallback callback;

   private:
    DISALLOW_COPY_AND_ASSIGN(DumpProcessArgs);
  };

  // Dumps the memory log for the given process into |args.output_file|. This
  // must be provided the memory map for the given process since that is not
  // tracked as part of the normal allocation process. When
  // |hop_to_connection_thread| is |true|, the task is posted onto the
  // connection thread's task runner, and then back onto the current task
  // runner. This ensures that all queued tasks on the connection's thread are
  // flushed before the dump is executed.
  void DumpProcess(DumpProcessArgs args, bool hop_to_connection_thread);

  void DumpProcessesForTracing(
      mojom::Memlog::DumpProcessesForTracingCallback callback,
      memory_instrumentation::mojom::GlobalMemoryDumpPtr dump);

  void OnNewConnection(base::ScopedPlatformFile file, base::ProcessId pid);

 private:
  struct Connection;

  // This method is posted on the connection's thread, and immediately reposts
  // DumpProcess back to |task_runner|. This ensures that all queued tasks on
  // the connection's thread are flushed before the dump is executed.
  static void HopToConnectionThread(
      base::WeakPtr<MemlogConnectionManager> manager,
      DumpProcessArgs args,
      scoped_refptr<base::SequencedTaskRunner> task_runner);

  // Notification that a connection is complete. Unlike OnNewConnection which
  // is signaled by the pipe server, this is signaled by the allocation tracker
  // to ensure that the pipeline for this process has been flushed of all
  // messages.
  void OnConnectionComplete(base::ProcessId pid);

  void OnConnectionCompleteThunk(
      scoped_refptr<base::SequencedTaskRunner> main_loop,
      base::ProcessId process_id);

  BacktraceStorage backtrace_storage_;

  // Maps process ID to the connection information for it.
  base::flat_map<base::ProcessId, std::unique_ptr<Connection>> connections_;
  base::Lock connections_lock_;

  // Must be last.
  base::WeakPtrFactory<MemlogConnectionManager> weak_factory_;

  DISALLOW_COPY_AND_ASSIGN(MemlogConnectionManager);
};

}  // namespace profiling

#endif  // CHROME_PROFILING_MEMLOG_CONNECTION_MANAGER_H_