hal/HalLog.h
author Andrew McCreight <continuation@gmail.com>
Mon, 22 Apr 2019 16:34:51 +0000
changeset 470376 3073770e06f157040f4c64951b7e8425e1ad7bbe
parent 448947 6f3709b3878117466168c40affa7bca0b60cf75b
child 472094 e1993a1f09ac53cd1a04fdf6a87f8cad8e44f73e
permissions -rw-r--r--
Bug 1535403 - Take indirection into account for the CC optimizations for the outer window wrapper. r=peterv Most wrapper cached C++ objects are held alive by their wrapper. The cycle collector takes advantage of this in many classes and ignores the C++ object if the wrapper is marked black. However, this is not true for the outer window's wrapper. Instead, the outer window's wrapper keeps the inner window alive. The inner window usually keeps its outer window alive, but not after it has been unlinked. For reasons I do not yet understand, the outer window's wrapper can be kept alive after the inner window it is a proxy for is unlinked. This patch fixes the cycle collector optimization for the outer window by only applying it if the outer window still has a weak reference to the inner window, which it will until the inner no longer holds the outer alive. This in turn fixes, or at least helps fix, window leaks seen intermittently when the lifetime of outer windows and docshells are tied together. The code comment is based on a review comment by peterv. Differential Revision: https://phabricator.services.mozilla.com/D27981

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set sw=2 ts=8 et ft=cpp : */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_HalLog_h
#define mozilla_HalLog_h

#include "mozilla/Logging.h"

/*
 * HalLog.h contains internal macros and functions used for logging.
 *
 * This should be considered a private include and not used in non-HAL code.
 * To enable logging in non-debug builds define the PR_FORCE_LOG macro here.
 */

namespace mozilla {

namespace hal {

mozilla::LogModule *GetHalLog();
#define HAL_LOG(...) \
  MOZ_LOG(mozilla::hal::GetHalLog(), LogLevel::Debug, (__VA_ARGS__))
#define HAL_ERR(...) \
  MOZ_LOG(mozilla::hal::GetHalLog(), LogLevel::Error, (__VA_ARGS__))

}  // namespace hal

}  // namespace mozilla

#endif  // mozilla_HalLog_h