зеркало из https://github.com/mozilla/gecko-dev.git
4695 строки
145 KiB
C++
4695 строки
145 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* vim: set ts=8 sts=2 et sw=2 tw=80: */
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/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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// Portions of this file were originally under the following license:
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//
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// Copyright (C) 2006-2008 Jason Evans <jasone@FreeBSD.org>.
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// All rights reserved.
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// Copyright (C) 2007-2017 Mozilla Foundation.
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//
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions
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// are met:
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// 1. Redistributions of source code must retain the above copyright
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// notice(s), this list of conditions and the following disclaimer as
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// the first lines of this file unmodified other than the possible
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// addition of one or more copyright notices.
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// 2. Redistributions in binary form must reproduce the above copyright
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// notice(s), this list of conditions and the following disclaimer in
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// the documentation and/or other materials provided with the
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// distribution.
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//
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
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// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
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// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
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// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
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// WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
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// OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
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// EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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//
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// *****************************************************************************
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//
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// This allocator implementation is designed to provide scalable performance
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// for multi-threaded programs on multi-processor systems. The following
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// features are included for this purpose:
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//
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// + Multiple arenas are used if there are multiple CPUs, which reduces lock
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// contention and cache sloshing.
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//
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// + Cache line sharing between arenas is avoided for internal data
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// structures.
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//
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// + Memory is managed in chunks and runs (chunks can be split into runs),
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// rather than as individual pages. This provides a constant-time
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// mechanism for associating allocations with particular arenas.
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//
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// Allocation requests are rounded up to the nearest size class, and no record
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// of the original request size is maintained. Allocations are broken into
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// categories according to size class. Assuming runtime defaults, 4 kB pages
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// and a 16 byte quantum on a 32-bit system, the size classes in each category
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// are as follows:
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//
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// |=====================================|
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// | Category | Subcategory | Size |
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// |=====================================|
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// | Small | Tiny | 4 |
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// | | | 8 |
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// | |----------------+---------|
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// | | Quantum-spaced | 16 |
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// | | | 32 |
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// | | | 48 |
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// | | | ... |
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// | | | 480 |
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// | | | 496 |
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// | | | 512 |
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// | |----------------+---------|
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// | | Sub-page | 1 kB |
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// | | | 2 kB |
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// |=====================================|
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// | Large | 4 kB |
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// | | 8 kB |
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// | | 12 kB |
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// | | ... |
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// | | 1012 kB |
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// | | 1016 kB |
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// | | 1020 kB |
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// |=====================================|
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// | Huge | 1 MB |
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// | | 2 MB |
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// | | 3 MB |
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// | | ... |
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// |=====================================|
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//
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// NOTE: Due to Mozilla bug 691003, we cannot reserve less than one word for an
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// allocation on Linux or Mac. So on 32-bit *nix, the smallest bucket size is
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// 4 bytes, and on 64-bit, the smallest bucket size is 8 bytes.
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//
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// A different mechanism is used for each category:
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//
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// Small : Each size class is segregated into its own set of runs. Each run
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// maintains a bitmap of which regions are free/allocated.
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//
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// Large : Each allocation is backed by a dedicated run. Metadata are stored
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// in the associated arena chunk header maps.
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//
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// Huge : Each allocation is backed by a dedicated contiguous set of chunks.
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// Metadata are stored in a separate red-black tree.
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//
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// *****************************************************************************
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#include "mozmemory_wrap.h"
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#include "mozjemalloc.h"
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#include "mozjemalloc_types.h"
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#include <cstring>
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#include <cerrno>
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#ifdef XP_WIN
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# include <io.h>
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# include <windows.h>
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#else
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# include <sys/mman.h>
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# include <unistd.h>
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#endif
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#ifdef XP_DARWIN
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# include <libkern/OSAtomic.h>
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# include <mach/mach_init.h>
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# include <mach/vm_map.h>
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#endif
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#include "mozilla/Atomics.h"
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#include "mozilla/Alignment.h"
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#include "mozilla/ArrayUtils.h"
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#include "mozilla/Assertions.h"
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#include "mozilla/Attributes.h"
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#include "mozilla/CheckedInt.h"
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#include "mozilla/DoublyLinkedList.h"
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#include "mozilla/Likely.h"
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#include "mozilla/MathAlgorithms.h"
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#include "mozilla/RandomNum.h"
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#include "mozilla/Sprintf.h"
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// Note: MozTaggedAnonymousMmap() could call an LD_PRELOADed mmap
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// instead of the one defined here; use only MozTagAnonymousMemory().
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#include "mozilla/TaggedAnonymousMemory.h"
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#include "mozilla/ThreadLocal.h"
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#include "mozilla/UniquePtr.h"
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#include "mozilla/Unused.h"
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#include "mozilla/fallible.h"
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#include "rb.h"
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#include "Mutex.h"
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#include "Utils.h"
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using namespace mozilla;
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// On Linux, we use madvise(MADV_DONTNEED) to release memory back to the
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// operating system. If we release 1MB of live pages with MADV_DONTNEED, our
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// RSS will decrease by 1MB (almost) immediately.
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//
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// On Mac, we use madvise(MADV_FREE). Unlike MADV_DONTNEED on Linux, MADV_FREE
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// on Mac doesn't cause the OS to release the specified pages immediately; the
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// OS keeps them in our process until the machine comes under memory pressure.
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//
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// It's therefore difficult to measure the process's RSS on Mac, since, in the
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// absence of memory pressure, the contribution from the heap to RSS will not
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// decrease due to our madvise calls.
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//
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// We therefore define MALLOC_DOUBLE_PURGE on Mac. This causes jemalloc to
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// track which pages have been MADV_FREE'd. You can then call
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// jemalloc_purge_freed_pages(), which will force the OS to release those
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// MADV_FREE'd pages, making the process's RSS reflect its true memory usage.
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//
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// The jemalloc_purge_freed_pages definition in memory/build/mozmemory.h needs
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// to be adjusted if MALLOC_DOUBLE_PURGE is ever enabled on Linux.
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#ifdef XP_DARWIN
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# define MALLOC_DOUBLE_PURGE
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#endif
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#ifdef XP_WIN
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# define MALLOC_DECOMMIT
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#endif
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// When MALLOC_STATIC_PAGESIZE is defined, the page size is fixed at
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// compile-time for better performance, as opposed to determined at
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// runtime. Some platforms can have different page sizes at runtime
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// depending on kernel configuration, so they are opted out by default.
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// Debug builds are opted out too, for test coverage.
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#ifndef MOZ_DEBUG
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# if !defined(__ia64__) && !defined(__sparc__) && !defined(__mips__) && \
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!defined(__aarch64__)
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# define MALLOC_STATIC_PAGESIZE 1
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# endif
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#endif
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#ifdef XP_WIN
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# define STDERR_FILENO 2
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// Implement getenv without using malloc.
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static char mozillaMallocOptionsBuf[64];
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# define getenv xgetenv
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static char* getenv(const char* name) {
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if (GetEnvironmentVariableA(name, mozillaMallocOptionsBuf,
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sizeof(mozillaMallocOptionsBuf)) > 0) {
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return mozillaMallocOptionsBuf;
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}
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return nullptr;
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}
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#endif
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#ifndef XP_WIN
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// Newer Linux systems support MADV_FREE, but we're not supporting
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// that properly. bug #1406304.
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# if defined(XP_LINUX) && defined(MADV_FREE)
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# undef MADV_FREE
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# endif
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# ifndef MADV_FREE
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# define MADV_FREE MADV_DONTNEED
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# endif
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#endif
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// Some tools, such as /dev/dsp wrappers, LD_PRELOAD libraries that
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// happen to override mmap() and call dlsym() from their overridden
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// mmap(). The problem is that dlsym() calls malloc(), and this ends
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// up in a dead lock in jemalloc.
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// On these systems, we prefer to directly use the system call.
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// We do that for Linux systems and kfreebsd with GNU userland.
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// Note sanity checks are not done (alignment of offset, ...) because
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// the uses of mmap are pretty limited, in jemalloc.
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//
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// On Alpha, glibc has a bug that prevents syscall() to work for system
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// calls with 6 arguments.
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#if (defined(XP_LINUX) && !defined(__alpha__)) || \
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(defined(__FreeBSD_kernel__) && defined(__GLIBC__))
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# include <sys/syscall.h>
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# if defined(SYS_mmap) || defined(SYS_mmap2)
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static inline void* _mmap(void* addr, size_t length, int prot, int flags,
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int fd, off_t offset) {
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// S390 only passes one argument to the mmap system call, which is a
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// pointer to a structure containing the arguments.
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# ifdef __s390__
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struct {
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void* addr;
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size_t length;
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long prot;
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long flags;
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long fd;
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off_t offset;
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} args = {addr, length, prot, flags, fd, offset};
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return (void*)syscall(SYS_mmap, &args);
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# else
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# if defined(ANDROID) && defined(__aarch64__) && defined(SYS_mmap2)
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// Android NDK defines SYS_mmap2 for AArch64 despite it not supporting mmap2.
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# undef SYS_mmap2
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# endif
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# ifdef SYS_mmap2
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return (void*)syscall(SYS_mmap2, addr, length, prot, flags, fd, offset >> 12);
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# else
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return (void*)syscall(SYS_mmap, addr, length, prot, flags, fd, offset);
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# endif
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# endif
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}
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# define mmap _mmap
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# define munmap(a, l) syscall(SYS_munmap, a, l)
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# endif
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#endif
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// ***************************************************************************
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// Structures for chunk headers for chunks used for non-huge allocations.
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struct arena_t;
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// Each element of the chunk map corresponds to one page within the chunk.
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struct arena_chunk_map_t {
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// Linkage for run trees. There are two disjoint uses:
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//
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// 1) arena_t's tree or available runs.
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// 2) arena_run_t conceptually uses this linkage for in-use non-full
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// runs, rather than directly embedding linkage.
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RedBlackTreeNode<arena_chunk_map_t> link;
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// Run address (or size) and various flags are stored together. The bit
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// layout looks like (assuming 32-bit system):
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//
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// ???????? ???????? ????---- -mckdzla
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//
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// ? : Unallocated: Run address for first/last pages, unset for internal
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// pages.
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// Small: Run address.
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// Large: Run size for first page, unset for trailing pages.
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// - : Unused.
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// m : MADV_FREE/MADV_DONTNEED'ed?
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// c : decommitted?
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// k : key?
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// d : dirty?
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// z : zeroed?
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// l : large?
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// a : allocated?
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//
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// Following are example bit patterns for the three types of runs.
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//
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// r : run address
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// s : run size
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// x : don't care
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// - : 0
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// [cdzla] : bit set
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//
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// Unallocated:
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// ssssssss ssssssss ssss---- --c-----
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// xxxxxxxx xxxxxxxx xxxx---- ----d---
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// ssssssss ssssssss ssss---- -----z--
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//
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// Small:
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// rrrrrrrr rrrrrrrr rrrr---- -------a
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// rrrrrrrr rrrrrrrr rrrr---- -------a
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// rrrrrrrr rrrrrrrr rrrr---- -------a
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//
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// Large:
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// ssssssss ssssssss ssss---- ------la
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// -------- -------- -------- ------la
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// -------- -------- -------- ------la
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size_t bits;
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// Note that CHUNK_MAP_DECOMMITTED's meaning varies depending on whether
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// MALLOC_DECOMMIT and MALLOC_DOUBLE_PURGE are defined.
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//
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// If MALLOC_DECOMMIT is defined, a page which is CHUNK_MAP_DECOMMITTED must be
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// re-committed with pages_commit() before it may be touched. If
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// MALLOC_DECOMMIT is defined, MALLOC_DOUBLE_PURGE may not be defined.
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//
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// If neither MALLOC_DECOMMIT nor MALLOC_DOUBLE_PURGE is defined, pages which
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// are madvised (with either MADV_DONTNEED or MADV_FREE) are marked with
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// CHUNK_MAP_MADVISED.
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//
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// Otherwise, if MALLOC_DECOMMIT is not defined and MALLOC_DOUBLE_PURGE is
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// defined, then a page which is madvised is marked as CHUNK_MAP_MADVISED.
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// When it's finally freed with jemalloc_purge_freed_pages, the page is marked
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// as CHUNK_MAP_DECOMMITTED.
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#define CHUNK_MAP_MADVISED ((size_t)0x40U)
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#define CHUNK_MAP_DECOMMITTED ((size_t)0x20U)
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#define CHUNK_MAP_MADVISED_OR_DECOMMITTED \
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(CHUNK_MAP_MADVISED | CHUNK_MAP_DECOMMITTED)
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#define CHUNK_MAP_KEY ((size_t)0x10U)
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#define CHUNK_MAP_DIRTY ((size_t)0x08U)
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#define CHUNK_MAP_ZEROED ((size_t)0x04U)
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#define CHUNK_MAP_LARGE ((size_t)0x02U)
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#define CHUNK_MAP_ALLOCATED ((size_t)0x01U)
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};
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// Arena chunk header.
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struct arena_chunk_t {
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// Arena that owns the chunk.
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arena_t* arena;
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// Linkage for the arena's tree of dirty chunks.
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RedBlackTreeNode<arena_chunk_t> link_dirty;
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#ifdef MALLOC_DOUBLE_PURGE
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// If we're double-purging, we maintain a linked list of chunks which
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// have pages which have been madvise(MADV_FREE)'d but not explicitly
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// purged.
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//
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// We're currently lazy and don't remove a chunk from this list when
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// all its madvised pages are recommitted.
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DoublyLinkedListElement<arena_chunk_t> chunks_madvised_elem;
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#endif
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// Number of dirty pages.
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size_t ndirty;
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// Map of pages within chunk that keeps track of free/large/small.
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arena_chunk_map_t map[1]; // Dynamically sized.
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};
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// ***************************************************************************
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// Constants defining allocator size classes and behavior.
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// Maximum size of L1 cache line. This is used to avoid cache line aliasing,
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// so over-estimates are okay (up to a point), but under-estimates will
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// negatively affect performance.
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static const size_t kCacheLineSize = 64;
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// Smallest size class to support. On Windows the smallest allocation size
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// must be 8 bytes on 32-bit, 16 bytes on 64-bit. On Linux and Mac, even
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// malloc(1) must reserve a word's worth of memory (see Mozilla bug 691003).
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#ifdef XP_WIN
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static const size_t kMinTinyClass = sizeof(void*) * 2;
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#else
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static const size_t kMinTinyClass = sizeof(void*);
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#endif
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// Maximum tiny size class.
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static const size_t kMaxTinyClass = 8;
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// Amount (quantum) separating quantum-spaced size classes.
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static const size_t kQuantum = 16;
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static const size_t kQuantumMask = kQuantum - 1;
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// Smallest quantum-spaced size classes. It could actually also be labelled a
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// tiny allocation, and is spaced as such from the largest tiny size class.
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// Tiny classes being powers of 2, this is twice as large as the largest of
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// them.
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static const size_t kMinQuantumClass = kMaxTinyClass * 2;
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// Largest quantum-spaced size classes.
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static const size_t kMaxQuantumClass = 512;
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static_assert(kMaxQuantumClass % kQuantum == 0,
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"kMaxQuantumClass is not a multiple of kQuantum");
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// Number of (2^n)-spaced tiny classes.
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static const size_t kNumTinyClasses =
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LOG2(kMinQuantumClass) - LOG2(kMinTinyClass);
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// Number of quantum-spaced classes.
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static const size_t kNumQuantumClasses = kMaxQuantumClass / kQuantum;
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// Size and alignment of memory chunks that are allocated by the OS's virtual
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// memory system.
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static const size_t kChunkSize = 1_MiB;
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static const size_t kChunkSizeMask = kChunkSize - 1;
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#ifdef MALLOC_STATIC_PAGESIZE
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// VM page size. It must divide the runtime CPU page size or the code
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// will abort.
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// Platform specific page size conditions copied from js/public/HeapAPI.h
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# if (defined(SOLARIS) || defined(__FreeBSD__)) && \
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(defined(__sparc) || defined(__sparcv9) || defined(__ia64))
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static const size_t gPageSize = 8_KiB;
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# elif defined(__powerpc64__)
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static const size_t gPageSize = 64_KiB;
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# else
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static const size_t gPageSize = 4_KiB;
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# endif
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#else
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static size_t gPageSize;
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#endif
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#ifdef MALLOC_STATIC_PAGESIZE
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# define DECLARE_GLOBAL(type, name)
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# define DEFINE_GLOBALS
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# define END_GLOBALS
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# define DEFINE_GLOBAL(type) static const type
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# define GLOBAL_LOG2 LOG2
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# define GLOBAL_ASSERT_HELPER1(x) static_assert(x, # x)
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# define GLOBAL_ASSERT_HELPER2(x, y) static_assert(x, y)
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# define GLOBAL_ASSERT(...) \
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MACRO_CALL( \
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MOZ_PASTE_PREFIX_AND_ARG_COUNT(GLOBAL_ASSERT_HELPER, __VA_ARGS__), \
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(__VA_ARGS__))
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#else
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# define DECLARE_GLOBAL(type, name) static type name;
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# define DEFINE_GLOBALS static void DefineGlobals() {
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# define END_GLOBALS }
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# define DEFINE_GLOBAL(type)
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# define GLOBAL_LOG2 FloorLog2
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# define GLOBAL_ASSERT MOZ_RELEASE_ASSERT
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#endif
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DECLARE_GLOBAL(size_t, gMaxSubPageClass)
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DECLARE_GLOBAL(uint8_t, gNumSubPageClasses)
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DECLARE_GLOBAL(uint8_t, gPageSize2Pow)
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DECLARE_GLOBAL(size_t, gPageSizeMask)
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DECLARE_GLOBAL(size_t, gChunkNumPages)
|
|
DECLARE_GLOBAL(size_t, gChunkHeaderNumPages)
|
|
DECLARE_GLOBAL(size_t, gMaxLargeClass)
|
|
|
|
DEFINE_GLOBALS
|
|
// Largest sub-page size class.
|
|
DEFINE_GLOBAL(size_t) gMaxSubPageClass = gPageSize / 2;
|
|
|
|
// Max size class for bins.
|
|
#define gMaxBinClass gMaxSubPageClass
|
|
|
|
// Number of (2^n)-spaced sub-page bins.
|
|
DEFINE_GLOBAL(uint8_t)
|
|
gNumSubPageClasses = GLOBAL_LOG2(gMaxSubPageClass) - LOG2(kMaxQuantumClass);
|
|
|
|
DEFINE_GLOBAL(uint8_t) gPageSize2Pow = GLOBAL_LOG2(gPageSize);
|
|
DEFINE_GLOBAL(size_t) gPageSizeMask = gPageSize - 1;
|
|
|
|
// Number of pages in a chunk.
|
|
DEFINE_GLOBAL(size_t) gChunkNumPages = kChunkSize >> gPageSize2Pow;
|
|
|
|
// Number of pages necessary for a chunk header.
|
|
DEFINE_GLOBAL(size_t)
|
|
gChunkHeaderNumPages =
|
|
((sizeof(arena_chunk_t) + sizeof(arena_chunk_map_t) * (gChunkNumPages - 1) +
|
|
gPageSizeMask) &
|
|
~gPageSizeMask) >>
|
|
gPageSize2Pow;
|
|
|
|
// One chunk, minus the header, minus a guard page
|
|
DEFINE_GLOBAL(size_t)
|
|
gMaxLargeClass =
|
|
kChunkSize - gPageSize - (gChunkHeaderNumPages << gPageSize2Pow);
|
|
|
|
// Various sanity checks that regard configuration.
|
|
GLOBAL_ASSERT(1ULL << gPageSize2Pow == gPageSize,
|
|
"Page size is not a power of two");
|
|
GLOBAL_ASSERT(kQuantum >= sizeof(void*));
|
|
GLOBAL_ASSERT(kQuantum <= gPageSize);
|
|
GLOBAL_ASSERT(kChunkSize >= gPageSize);
|
|
GLOBAL_ASSERT(kQuantum * 4 <= kChunkSize);
|
|
END_GLOBALS
|
|
|
|
// Recycle at most 128 MiB of chunks. This means we retain at most
|
|
// 6.25% of the process address space on a 32-bit OS for later use.
|
|
static const size_t gRecycleLimit = 128_MiB;
|
|
|
|
// The current amount of recycled bytes, updated atomically. Malloc may be
|
|
// called non-deterministically when recording/replaying, so this atomic's
|
|
// accesses are not recorded.
|
|
static Atomic<size_t, ReleaseAcquire, recordreplay::Behavior::DontPreserve>
|
|
gRecycledSize;
|
|
|
|
// Maximum number of dirty pages per arena.
|
|
#define DIRTY_MAX_DEFAULT (1U << 8)
|
|
|
|
static size_t opt_dirty_max = DIRTY_MAX_DEFAULT;
|
|
|
|
// Return the smallest chunk multiple that is >= s.
|
|
#define CHUNK_CEILING(s) (((s) + kChunkSizeMask) & ~kChunkSizeMask)
|
|
|
|
// Return the smallest cacheline multiple that is >= s.
|
|
#define CACHELINE_CEILING(s) \
|
|
(((s) + (kCacheLineSize - 1)) & ~(kCacheLineSize - 1))
|
|
|
|
// Return the smallest quantum multiple that is >= a.
|
|
#define QUANTUM_CEILING(a) (((a) + (kQuantumMask)) & ~(kQuantumMask))
|
|
|
|
// Return the smallest pagesize multiple that is >= s.
|
|
#define PAGE_CEILING(s) (((s) + gPageSizeMask) & ~gPageSizeMask)
|
|
|
|
// ***************************************************************************
|
|
// MALLOC_DECOMMIT and MALLOC_DOUBLE_PURGE are mutually exclusive.
|
|
#if defined(MALLOC_DECOMMIT) && defined(MALLOC_DOUBLE_PURGE)
|
|
# error MALLOC_DECOMMIT and MALLOC_DOUBLE_PURGE are mutually exclusive.
|
|
#endif
|
|
|
|
static void* base_alloc(size_t aSize);
|
|
|
|
// Set to true once the allocator has been initialized.
|
|
#if defined(_MSC_VER) && !defined(__clang__)
|
|
// MSVC may create a static initializer for an Atomic<bool>, which may actually
|
|
// run after `malloc_init` has been called once, which triggers multiple
|
|
// initializations.
|
|
// We work around the problem by not using an Atomic<bool> at all. There is a
|
|
// theoretical problem with using `malloc_initialized` non-atomically, but
|
|
// practically, this is only true if `malloc_init` is never called before
|
|
// threads are created.
|
|
static bool malloc_initialized;
|
|
#else
|
|
// Malloc may be called non-deterministically when recording/replaying, so this
|
|
// atomic's accesses are not recorded.
|
|
static Atomic<bool, SequentiallyConsistent,
|
|
recordreplay::Behavior::DontPreserve>
|
|
malloc_initialized;
|
|
#endif
|
|
|
|
static StaticMutex gInitLock = {STATIC_MUTEX_INIT};
|
|
|
|
// ***************************************************************************
|
|
// Statistics data structures.
|
|
|
|
struct arena_stats_t {
|
|
// Number of bytes currently mapped.
|
|
size_t mapped;
|
|
|
|
// Current number of committed pages.
|
|
size_t committed;
|
|
|
|
// Per-size-category statistics.
|
|
size_t allocated_small;
|
|
|
|
size_t allocated_large;
|
|
};
|
|
|
|
// ***************************************************************************
|
|
// Extent data structures.
|
|
|
|
enum ChunkType {
|
|
UNKNOWN_CHUNK,
|
|
ZEROED_CHUNK, // chunk only contains zeroes.
|
|
ARENA_CHUNK, // used to back arena runs created by arena_t::AllocRun.
|
|
HUGE_CHUNK, // used to back huge allocations (e.g. arena_t::MallocHuge).
|
|
RECYCLED_CHUNK, // chunk has been stored for future use by chunk_recycle.
|
|
};
|
|
|
|
// Tree of extents.
|
|
struct extent_node_t {
|
|
// Linkage for the size/address-ordered tree.
|
|
RedBlackTreeNode<extent_node_t> mLinkBySize;
|
|
|
|
// Linkage for the address-ordered tree.
|
|
RedBlackTreeNode<extent_node_t> mLinkByAddr;
|
|
|
|
// Pointer to the extent that this tree node is responsible for.
|
|
void* mAddr;
|
|
|
|
// Total region size.
|
|
size_t mSize;
|
|
|
|
union {
|
|
// What type of chunk is there; used for chunk recycling.
|
|
ChunkType mChunkType;
|
|
|
|
// A pointer to the associated arena, for huge allocations.
|
|
arena_t* mArena;
|
|
};
|
|
};
|
|
|
|
struct ExtentTreeSzTrait {
|
|
static RedBlackTreeNode<extent_node_t>& GetTreeNode(extent_node_t* aThis) {
|
|
return aThis->mLinkBySize;
|
|
}
|
|
|
|
static inline Order Compare(extent_node_t* aNode, extent_node_t* aOther) {
|
|
Order ret = CompareInt(aNode->mSize, aOther->mSize);
|
|
return (ret != Order::eEqual) ? ret
|
|
: CompareAddr(aNode->mAddr, aOther->mAddr);
|
|
}
|
|
};
|
|
|
|
struct ExtentTreeTrait {
|
|
static RedBlackTreeNode<extent_node_t>& GetTreeNode(extent_node_t* aThis) {
|
|
return aThis->mLinkByAddr;
|
|
}
|
|
|
|
static inline Order Compare(extent_node_t* aNode, extent_node_t* aOther) {
|
|
return CompareAddr(aNode->mAddr, aOther->mAddr);
|
|
}
|
|
};
|
|
|
|
struct ExtentTreeBoundsTrait : public ExtentTreeTrait {
|
|
static inline Order Compare(extent_node_t* aKey, extent_node_t* aNode) {
|
|
uintptr_t key_addr = reinterpret_cast<uintptr_t>(aKey->mAddr);
|
|
uintptr_t node_addr = reinterpret_cast<uintptr_t>(aNode->mAddr);
|
|
size_t node_size = aNode->mSize;
|
|
|
|
// Is aKey within aNode?
|
|
if (node_addr <= key_addr && key_addr < node_addr + node_size) {
|
|
return Order::eEqual;
|
|
}
|
|
|
|
return CompareAddr(aKey->mAddr, aNode->mAddr);
|
|
}
|
|
};
|
|
|
|
// Describe size classes to which allocations are rounded up to.
|
|
// TODO: add large and huge types when the arena allocation code
|
|
// changes in a way that allows it to be beneficial.
|
|
class SizeClass {
|
|
public:
|
|
enum ClassType {
|
|
Tiny,
|
|
Quantum,
|
|
SubPage,
|
|
Large,
|
|
};
|
|
|
|
explicit inline SizeClass(size_t aSize) {
|
|
if (aSize <= kMaxTinyClass) {
|
|
mType = Tiny;
|
|
mSize = std::max(RoundUpPow2(aSize), kMinTinyClass);
|
|
} else if (aSize <= kMaxQuantumClass) {
|
|
mType = Quantum;
|
|
mSize = QUANTUM_CEILING(aSize);
|
|
} else if (aSize <= gMaxSubPageClass) {
|
|
mType = SubPage;
|
|
mSize = RoundUpPow2(aSize);
|
|
} else if (aSize <= gMaxLargeClass) {
|
|
mType = Large;
|
|
mSize = PAGE_CEILING(aSize);
|
|
} else {
|
|
MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE("Invalid size");
|
|
}
|
|
}
|
|
|
|
SizeClass& operator=(const SizeClass& aOther) = default;
|
|
|
|
bool operator==(const SizeClass& aOther) { return aOther.mSize == mSize; }
|
|
|
|
size_t Size() { return mSize; }
|
|
|
|
ClassType Type() { return mType; }
|
|
|
|
SizeClass Next() { return SizeClass(mSize + 1); }
|
|
|
|
private:
|
|
ClassType mType;
|
|
size_t mSize;
|
|
};
|
|
|
|
// ***************************************************************************
|
|
// Radix tree data structures.
|
|
//
|
|
// The number of bits passed to the template is the number of significant bits
|
|
// in an address to do a radix lookup with.
|
|
//
|
|
// An address is looked up by splitting it in kBitsPerLevel bit chunks, except
|
|
// the most significant bits, where the bit chunk is kBitsAtLevel1 which can be
|
|
// different if Bits is not a multiple of kBitsPerLevel.
|
|
//
|
|
// With e.g. sizeof(void*)=4, Bits=16 and kBitsPerLevel=8, an address is split
|
|
// like the following:
|
|
// 0x12345678 -> mRoot[0x12][0x34]
|
|
template <size_t Bits>
|
|
class AddressRadixTree {
|
|
// Size of each radix tree node (as a power of 2).
|
|
// This impacts tree depth.
|
|
#ifdef HAVE_64BIT_BUILD
|
|
static const size_t kNodeSize = kCacheLineSize;
|
|
#else
|
|
static const size_t kNodeSize = 16_KiB;
|
|
#endif
|
|
static const size_t kBitsPerLevel = LOG2(kNodeSize) - LOG2(sizeof(void*));
|
|
static const size_t kBitsAtLevel1 =
|
|
(Bits % kBitsPerLevel) ? Bits % kBitsPerLevel : kBitsPerLevel;
|
|
static const size_t kHeight = (Bits + kBitsPerLevel - 1) / kBitsPerLevel;
|
|
static_assert(kBitsAtLevel1 + (kHeight - 1) * kBitsPerLevel == Bits,
|
|
"AddressRadixTree parameters don't work out");
|
|
|
|
Mutex mLock;
|
|
void** mRoot;
|
|
|
|
public:
|
|
bool Init();
|
|
|
|
inline void* Get(void* aAddr);
|
|
|
|
// Returns whether the value was properly set.
|
|
inline bool Set(void* aAddr, void* aValue);
|
|
|
|
inline bool Unset(void* aAddr) { return Set(aAddr, nullptr); }
|
|
|
|
private:
|
|
inline void** GetSlot(void* aAddr, bool aCreate = false);
|
|
};
|
|
|
|
// ***************************************************************************
|
|
// Arena data structures.
|
|
|
|
struct arena_bin_t;
|
|
|
|
struct ArenaChunkMapLink {
|
|
static RedBlackTreeNode<arena_chunk_map_t>& GetTreeNode(
|
|
arena_chunk_map_t* aThis) {
|
|
return aThis->link;
|
|
}
|
|
};
|
|
|
|
struct ArenaRunTreeTrait : public ArenaChunkMapLink {
|
|
static inline Order Compare(arena_chunk_map_t* aNode,
|
|
arena_chunk_map_t* aOther) {
|
|
MOZ_ASSERT(aNode);
|
|
MOZ_ASSERT(aOther);
|
|
return CompareAddr(aNode, aOther);
|
|
}
|
|
};
|
|
|
|
struct ArenaAvailTreeTrait : public ArenaChunkMapLink {
|
|
static inline Order Compare(arena_chunk_map_t* aNode,
|
|
arena_chunk_map_t* aOther) {
|
|
size_t size1 = aNode->bits & ~gPageSizeMask;
|
|
size_t size2 = aOther->bits & ~gPageSizeMask;
|
|
Order ret = CompareInt(size1, size2);
|
|
return (ret != Order::eEqual)
|
|
? ret
|
|
: CompareAddr((aNode->bits & CHUNK_MAP_KEY) ? nullptr : aNode,
|
|
aOther);
|
|
}
|
|
};
|
|
|
|
struct ArenaDirtyChunkTrait {
|
|
static RedBlackTreeNode<arena_chunk_t>& GetTreeNode(arena_chunk_t* aThis) {
|
|
return aThis->link_dirty;
|
|
}
|
|
|
|
static inline Order Compare(arena_chunk_t* aNode, arena_chunk_t* aOther) {
|
|
MOZ_ASSERT(aNode);
|
|
MOZ_ASSERT(aOther);
|
|
return CompareAddr(aNode, aOther);
|
|
}
|
|
};
|
|
|
|
#ifdef MALLOC_DOUBLE_PURGE
|
|
namespace mozilla {
|
|
|
|
template <>
|
|
struct GetDoublyLinkedListElement<arena_chunk_t> {
|
|
static DoublyLinkedListElement<arena_chunk_t>& Get(arena_chunk_t* aThis) {
|
|
return aThis->chunks_madvised_elem;
|
|
}
|
|
};
|
|
} // namespace mozilla
|
|
#endif
|
|
|
|
struct arena_run_t {
|
|
#if defined(MOZ_DIAGNOSTIC_ASSERT_ENABLED)
|
|
uint32_t mMagic;
|
|
# define ARENA_RUN_MAGIC 0x384adf93
|
|
|
|
// On 64-bit platforms, having the arena_bin_t pointer following
|
|
// the mMagic field means there's padding between both fields, making
|
|
// the run header larger than necessary.
|
|
// But when MOZ_DIAGNOSTIC_ASSERT_ENABLED is not set, starting the
|
|
// header with this field followed by the arena_bin_t pointer yields
|
|
// the same padding. We do want the mMagic field to appear first, so
|
|
// depending whether MOZ_DIAGNOSTIC_ASSERT_ENABLED is set or not, we
|
|
// move some field to avoid padding.
|
|
|
|
// Number of free regions in run.
|
|
unsigned mNumFree;
|
|
#endif
|
|
|
|
// Bin this run is associated with.
|
|
arena_bin_t* mBin;
|
|
|
|
// Index of first element that might have a free region.
|
|
unsigned mRegionsMinElement;
|
|
|
|
#if !defined(MOZ_DIAGNOSTIC_ASSERT_ENABLED)
|
|
// Number of free regions in run.
|
|
unsigned mNumFree;
|
|
#endif
|
|
|
|
// Bitmask of in-use regions (0: in use, 1: free).
|
|
unsigned mRegionsMask[1]; // Dynamically sized.
|
|
};
|
|
|
|
struct arena_bin_t {
|
|
// Current run being used to service allocations of this bin's size
|
|
// class.
|
|
arena_run_t* mCurrentRun;
|
|
|
|
// Tree of non-full runs. This tree is used when looking for an
|
|
// existing run when mCurrentRun is no longer usable. We choose the
|
|
// non-full run that is lowest in memory; this policy tends to keep
|
|
// objects packed well, and it can also help reduce the number of
|
|
// almost-empty chunks.
|
|
RedBlackTree<arena_chunk_map_t, ArenaRunTreeTrait> mNonFullRuns;
|
|
|
|
// Bin's size class.
|
|
size_t mSizeClass;
|
|
|
|
// Total size of a run for this bin's size class.
|
|
size_t mRunSize;
|
|
|
|
// Total number of regions in a run for this bin's size class.
|
|
uint32_t mRunNumRegions;
|
|
|
|
// Number of elements in a run's mRegionsMask for this bin's size class.
|
|
uint32_t mRunNumRegionsMask;
|
|
|
|
// Offset of first region in a run for this bin's size class.
|
|
uint32_t mRunFirstRegionOffset;
|
|
|
|
// Current number of runs in this bin, full or otherwise.
|
|
unsigned long mNumRuns;
|
|
|
|
// Amount of overhead runs are allowed to have.
|
|
static constexpr double kRunOverhead = 1.6_percent;
|
|
static constexpr double kRunRelaxedOverhead = 2.4_percent;
|
|
|
|
// Initialize a bin for the given size class.
|
|
// The generated run sizes, for a page size of 4 KiB, are:
|
|
// size|run size|run size|run size|run
|
|
// class|size class|size class|size class|size
|
|
// 4 4 KiB 8 4 KiB 16 4 KiB 32 4 KiB
|
|
// 48 4 KiB 64 4 KiB 80 4 KiB 96 4 KiB
|
|
// 112 4 KiB 128 8 KiB 144 4 KiB 160 8 KiB
|
|
// 176 4 KiB 192 4 KiB 208 8 KiB 224 4 KiB
|
|
// 240 4 KiB 256 16 KiB 272 4 KiB 288 4 KiB
|
|
// 304 12 KiB 320 12 KiB 336 4 KiB 352 8 KiB
|
|
// 368 4 KiB 384 8 KiB 400 20 KiB 416 16 KiB
|
|
// 432 12 KiB 448 4 KiB 464 16 KiB 480 8 KiB
|
|
// 496 20 KiB 512 32 KiB 1024 64 KiB 2048 128 KiB
|
|
inline void Init(SizeClass aSizeClass);
|
|
};
|
|
|
|
struct arena_t {
|
|
#if defined(MOZ_DIAGNOSTIC_ASSERT_ENABLED)
|
|
uint32_t mMagic;
|
|
# define ARENA_MAGIC 0x947d3d24
|
|
#endif
|
|
|
|
arena_id_t mId;
|
|
// Linkage for the tree of arenas by id.
|
|
RedBlackTreeNode<arena_t> mLink;
|
|
|
|
// All operations on this arena require that lock be locked.
|
|
Mutex mLock;
|
|
|
|
arena_stats_t mStats;
|
|
|
|
private:
|
|
// Tree of dirty-page-containing chunks this arena manages.
|
|
RedBlackTree<arena_chunk_t, ArenaDirtyChunkTrait> mChunksDirty;
|
|
|
|
#ifdef MALLOC_DOUBLE_PURGE
|
|
// Head of a linked list of MADV_FREE'd-page-containing chunks this
|
|
// arena manages.
|
|
DoublyLinkedList<arena_chunk_t> mChunksMAdvised;
|
|
#endif
|
|
|
|
// In order to avoid rapid chunk allocation/deallocation when an arena
|
|
// oscillates right on the cusp of needing a new chunk, cache the most
|
|
// recently freed chunk. The spare is left in the arena's chunk trees
|
|
// until it is deleted.
|
|
//
|
|
// There is one spare chunk per arena, rather than one spare total, in
|
|
// order to avoid interactions between multiple threads that could make
|
|
// a single spare inadequate.
|
|
arena_chunk_t* mSpare;
|
|
|
|
public:
|
|
// Current count of pages within unused runs that are potentially
|
|
// dirty, and for which madvise(... MADV_FREE) has not been called. By
|
|
// tracking this, we can institute a limit on how much dirty unused
|
|
// memory is mapped for each arena.
|
|
size_t mNumDirty;
|
|
|
|
// Maximum value allowed for mNumDirty.
|
|
size_t mMaxDirty;
|
|
|
|
private:
|
|
// Size/address-ordered tree of this arena's available runs. This tree
|
|
// is used for first-best-fit run allocation.
|
|
RedBlackTree<arena_chunk_map_t, ArenaAvailTreeTrait> mRunsAvail;
|
|
|
|
public:
|
|
// mBins is used to store rings of free regions of the following sizes,
|
|
// assuming a 16-byte quantum, 4kB pagesize, and default MALLOC_OPTIONS.
|
|
//
|
|
// mBins[i] | size |
|
|
// --------+------+
|
|
// 0 | 2 |
|
|
// 1 | 4 |
|
|
// 2 | 8 |
|
|
// --------+------+
|
|
// 3 | 16 |
|
|
// 4 | 32 |
|
|
// 5 | 48 |
|
|
// 6 | 64 |
|
|
// : :
|
|
// : :
|
|
// 33 | 496 |
|
|
// 34 | 512 |
|
|
// --------+------+
|
|
// 35 | 1024 |
|
|
// 36 | 2048 |
|
|
// --------+------+
|
|
arena_bin_t mBins[1]; // Dynamically sized.
|
|
|
|
explicit arena_t(arena_params_t* aParams);
|
|
|
|
private:
|
|
void InitChunk(arena_chunk_t* aChunk, bool aZeroed);
|
|
|
|
void DeallocChunk(arena_chunk_t* aChunk);
|
|
|
|
arena_run_t* AllocRun(size_t aSize, bool aLarge, bool aZero);
|
|
|
|
void DallocRun(arena_run_t* aRun, bool aDirty);
|
|
|
|
MOZ_MUST_USE bool SplitRun(arena_run_t* aRun, size_t aSize, bool aLarge,
|
|
bool aZero);
|
|
|
|
void TrimRunHead(arena_chunk_t* aChunk, arena_run_t* aRun, size_t aOldSize,
|
|
size_t aNewSize);
|
|
|
|
void TrimRunTail(arena_chunk_t* aChunk, arena_run_t* aRun, size_t aOldSize,
|
|
size_t aNewSize, bool dirty);
|
|
|
|
arena_run_t* GetNonFullBinRun(arena_bin_t* aBin);
|
|
|
|
inline void* MallocSmall(size_t aSize, bool aZero);
|
|
|
|
void* MallocLarge(size_t aSize, bool aZero);
|
|
|
|
void* MallocHuge(size_t aSize, bool aZero);
|
|
|
|
void* PallocLarge(size_t aAlignment, size_t aSize, size_t aAllocSize);
|
|
|
|
void* PallocHuge(size_t aSize, size_t aAlignment, bool aZero);
|
|
|
|
void RallocShrinkLarge(arena_chunk_t* aChunk, void* aPtr, size_t aSize,
|
|
size_t aOldSize);
|
|
|
|
bool RallocGrowLarge(arena_chunk_t* aChunk, void* aPtr, size_t aSize,
|
|
size_t aOldSize);
|
|
|
|
void* RallocSmallOrLarge(void* aPtr, size_t aSize, size_t aOldSize);
|
|
|
|
void* RallocHuge(void* aPtr, size_t aSize, size_t aOldSize);
|
|
|
|
public:
|
|
inline void* Malloc(size_t aSize, bool aZero);
|
|
|
|
void* Palloc(size_t aAlignment, size_t aSize);
|
|
|
|
inline void DallocSmall(arena_chunk_t* aChunk, void* aPtr,
|
|
arena_chunk_map_t* aMapElm);
|
|
|
|
void DallocLarge(arena_chunk_t* aChunk, void* aPtr);
|
|
|
|
void* Ralloc(void* aPtr, size_t aSize, size_t aOldSize);
|
|
|
|
void Purge(bool aAll);
|
|
|
|
void HardPurge();
|
|
|
|
void* operator new(size_t aCount) = delete;
|
|
|
|
void* operator new(size_t aCount, const fallible_t&)
|
|
#if !defined(_MSC_VER) || defined(_CPPUNWIND)
|
|
noexcept
|
|
#endif
|
|
{
|
|
MOZ_ASSERT(aCount == sizeof(arena_t));
|
|
// Allocate enough space for trailing bins.
|
|
return base_alloc(
|
|
aCount + (sizeof(arena_bin_t) * (kNumTinyClasses + kNumQuantumClasses +
|
|
gNumSubPageClasses - 1)));
|
|
}
|
|
|
|
void operator delete(void*) = delete;
|
|
};
|
|
|
|
struct ArenaTreeTrait {
|
|
static RedBlackTreeNode<arena_t>& GetTreeNode(arena_t* aThis) {
|
|
return aThis->mLink;
|
|
}
|
|
|
|
static inline Order Compare(arena_t* aNode, arena_t* aOther) {
|
|
MOZ_ASSERT(aNode);
|
|
MOZ_ASSERT(aOther);
|
|
return CompareInt(aNode->mId, aOther->mId);
|
|
}
|
|
};
|
|
|
|
// Bookkeeping for all the arenas used by the allocator.
|
|
// Arenas are separated in two categories:
|
|
// - "private" arenas, used through the moz_arena_* API
|
|
// - all the other arenas: the default arena, and thread-local arenas,
|
|
// used by the standard API.
|
|
class ArenaCollection {
|
|
public:
|
|
bool Init() {
|
|
mArenas.Init();
|
|
mPrivateArenas.Init();
|
|
arena_params_t params;
|
|
// The main arena allows more dirty pages than the default for other arenas.
|
|
params.mMaxDirty = opt_dirty_max;
|
|
mDefaultArena =
|
|
mLock.Init() ? CreateArena(/* IsPrivate = */ false, ¶ms) : nullptr;
|
|
return bool(mDefaultArena);
|
|
}
|
|
|
|
inline arena_t* GetById(arena_id_t aArenaId, bool aIsPrivate);
|
|
|
|
arena_t* CreateArena(bool aIsPrivate, arena_params_t* aParams);
|
|
|
|
void DisposeArena(arena_t* aArena) {
|
|
MutexAutoLock lock(mLock);
|
|
(mPrivateArenas.Search(aArena) ? mPrivateArenas : mArenas).Remove(aArena);
|
|
// The arena is leaked, and remaining allocations in it still are alive
|
|
// until they are freed. After that, the arena will be empty but still
|
|
// taking have at least a chunk taking address space. TODO: bug 1364359.
|
|
}
|
|
|
|
using Tree = RedBlackTree<arena_t, ArenaTreeTrait>;
|
|
|
|
struct Iterator : Tree::Iterator {
|
|
explicit Iterator(Tree* aTree, Tree* aSecondTree)
|
|
: Tree::Iterator(aTree), mNextTree(aSecondTree) {}
|
|
|
|
Item<Iterator> begin() {
|
|
return Item<Iterator>(this, *Tree::Iterator::begin());
|
|
}
|
|
|
|
Item<Iterator> end() { return Item<Iterator>(this, nullptr); }
|
|
|
|
arena_t* Next() {
|
|
arena_t* result = Tree::Iterator::Next();
|
|
if (!result && mNextTree) {
|
|
new (this) Iterator(mNextTree, nullptr);
|
|
result = *Tree::Iterator::begin();
|
|
}
|
|
return result;
|
|
}
|
|
|
|
private:
|
|
Tree* mNextTree;
|
|
};
|
|
|
|
Iterator iter() { return Iterator(&mArenas, &mPrivateArenas); }
|
|
|
|
inline arena_t* GetDefault() { return mDefaultArena; }
|
|
|
|
Mutex mLock;
|
|
|
|
private:
|
|
inline arena_t* GetByIdInternal(arena_id_t aArenaId, bool aIsPrivate);
|
|
|
|
arena_t* mDefaultArena;
|
|
arena_id_t mLastPublicArenaId;
|
|
Tree mArenas;
|
|
Tree mPrivateArenas;
|
|
};
|
|
|
|
static ArenaCollection gArenas;
|
|
|
|
// ******
|
|
// Chunks.
|
|
static AddressRadixTree<(sizeof(void*) << 3) - LOG2(kChunkSize)> gChunkRTree;
|
|
|
|
// Protects chunk-related data structures.
|
|
static Mutex chunks_mtx;
|
|
|
|
// Trees of chunks that were previously allocated (trees differ only in node
|
|
// ordering). These are used when allocating chunks, in an attempt to re-use
|
|
// address space. Depending on function, different tree orderings are needed,
|
|
// which is why there are two trees with the same contents.
|
|
static RedBlackTree<extent_node_t, ExtentTreeSzTrait> gChunksBySize;
|
|
static RedBlackTree<extent_node_t, ExtentTreeTrait> gChunksByAddress;
|
|
|
|
// Protects huge allocation-related data structures.
|
|
static Mutex huge_mtx;
|
|
|
|
// Tree of chunks that are stand-alone huge allocations.
|
|
static RedBlackTree<extent_node_t, ExtentTreeTrait> huge;
|
|
|
|
// Huge allocation statistics.
|
|
static size_t huge_allocated;
|
|
static size_t huge_mapped;
|
|
|
|
// **************************
|
|
// base (internal allocation).
|
|
|
|
// Current pages that are being used for internal memory allocations. These
|
|
// pages are carved up in cacheline-size quanta, so that there is no chance of
|
|
// false cache line sharing.
|
|
|
|
static void* base_pages;
|
|
static void* base_next_addr;
|
|
static void* base_next_decommitted;
|
|
static void* base_past_addr; // Addr immediately past base_pages.
|
|
static extent_node_t* base_nodes;
|
|
static Mutex base_mtx;
|
|
static size_t base_mapped;
|
|
static size_t base_committed;
|
|
|
|
// ******
|
|
// Arenas.
|
|
|
|
// The arena associated with the current thread (per
|
|
// jemalloc_thread_local_arena) On OSX, __thread/thread_local circles back
|
|
// calling malloc to allocate storage on first access on each thread, which
|
|
// leads to an infinite loop, but pthread-based TLS somehow doesn't have this
|
|
// problem.
|
|
#if !defined(XP_DARWIN)
|
|
static MOZ_THREAD_LOCAL(arena_t*) thread_arena;
|
|
#else
|
|
static detail::ThreadLocal<arena_t*, detail::ThreadLocalKeyStorage>
|
|
thread_arena;
|
|
#endif
|
|
|
|
// *****************************
|
|
// Runtime configuration options.
|
|
|
|
const uint8_t kAllocJunk = 0xe4;
|
|
const uint8_t kAllocPoison = 0xe5;
|
|
|
|
#ifdef MOZ_DEBUG
|
|
static bool opt_junk = true;
|
|
static bool opt_zero = false;
|
|
#else
|
|
static const bool opt_junk = false;
|
|
static const bool opt_zero = false;
|
|
#endif
|
|
|
|
// ***************************************************************************
|
|
// Begin forward declarations.
|
|
|
|
static void* chunk_alloc(size_t aSize, size_t aAlignment, bool aBase,
|
|
bool* aZeroed = nullptr);
|
|
static void chunk_dealloc(void* aChunk, size_t aSize, ChunkType aType);
|
|
static void chunk_ensure_zero(void* aPtr, size_t aSize, bool aZeroed);
|
|
static void huge_dalloc(void* aPtr, arena_t* aArena);
|
|
static bool malloc_init_hard();
|
|
|
|
#ifdef XP_DARWIN
|
|
# define FORK_HOOK extern "C"
|
|
#else
|
|
# define FORK_HOOK static
|
|
#endif
|
|
FORK_HOOK void _malloc_prefork(void);
|
|
FORK_HOOK void _malloc_postfork_parent(void);
|
|
FORK_HOOK void _malloc_postfork_child(void);
|
|
|
|
// End forward declarations.
|
|
// ***************************************************************************
|
|
|
|
// FreeBSD's pthreads implementation calls malloc(3), so the malloc
|
|
// implementation has to take pains to avoid infinite recursion during
|
|
// initialization.
|
|
// Returns whether the allocator was successfully initialized.
|
|
static inline bool malloc_init() {
|
|
if (malloc_initialized == false) {
|
|
return malloc_init_hard();
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
static void _malloc_message(const char* p) {
|
|
#if !defined(XP_WIN)
|
|
# define _write write
|
|
#endif
|
|
// Pretend to check _write() errors to suppress gcc warnings about
|
|
// warn_unused_result annotations in some versions of glibc headers.
|
|
if (_write(STDERR_FILENO, p, (unsigned int)strlen(p)) < 0) {
|
|
return;
|
|
}
|
|
}
|
|
|
|
template <typename... Args>
|
|
static void _malloc_message(const char* p, Args... args) {
|
|
_malloc_message(p);
|
|
_malloc_message(args...);
|
|
}
|
|
|
|
#ifdef ANDROID
|
|
// Android's pthread.h does not declare pthread_atfork() until SDK 21.
|
|
extern "C" MOZ_EXPORT int pthread_atfork(void (*)(void), void (*)(void),
|
|
void (*)(void));
|
|
#endif
|
|
|
|
// ***************************************************************************
|
|
// Begin Utility functions/macros.
|
|
|
|
// Return the chunk address for allocation address a.
|
|
static inline arena_chunk_t* GetChunkForPtr(const void* aPtr) {
|
|
return (arena_chunk_t*)(uintptr_t(aPtr) & ~kChunkSizeMask);
|
|
}
|
|
|
|
// Return the chunk offset of address a.
|
|
static inline size_t GetChunkOffsetForPtr(const void* aPtr) {
|
|
return (size_t)(uintptr_t(aPtr) & kChunkSizeMask);
|
|
}
|
|
|
|
static inline const char* _getprogname(void) { return "<jemalloc>"; }
|
|
|
|
// Fill the given range of memory with zeroes or junk depending on opt_junk and
|
|
// opt_zero. Callers can force filling with zeroes through the aForceZero
|
|
// argument.
|
|
static inline void ApplyZeroOrJunk(void* aPtr, size_t aSize) {
|
|
if (opt_junk) {
|
|
memset(aPtr, kAllocJunk, aSize);
|
|
} else if (opt_zero) {
|
|
memset(aPtr, 0, aSize);
|
|
}
|
|
}
|
|
|
|
// ***************************************************************************
|
|
|
|
static inline void pages_decommit(void* aAddr, size_t aSize) {
|
|
#ifdef XP_WIN
|
|
// The region starting at addr may have been allocated in multiple calls
|
|
// to VirtualAlloc and recycled, so decommitting the entire region in one
|
|
// go may not be valid. However, since we allocate at least a chunk at a
|
|
// time, we may touch any region in chunksized increments.
|
|
size_t pages_size = std::min(aSize, kChunkSize - GetChunkOffsetForPtr(aAddr));
|
|
while (aSize > 0) {
|
|
// This will cause Access Violation on read and write and thus act as a
|
|
// guard page or region as well.
|
|
if (!VirtualFree(aAddr, pages_size, MEM_DECOMMIT)) {
|
|
MOZ_CRASH();
|
|
}
|
|
aAddr = (void*)((uintptr_t)aAddr + pages_size);
|
|
aSize -= pages_size;
|
|
pages_size = std::min(aSize, kChunkSize);
|
|
}
|
|
#else
|
|
if (mmap(aAddr, aSize, PROT_NONE, MAP_FIXED | MAP_PRIVATE | MAP_ANON, -1,
|
|
0) == MAP_FAILED) {
|
|
MOZ_CRASH();
|
|
}
|
|
MozTagAnonymousMemory(aAddr, aSize, "jemalloc-decommitted");
|
|
#endif
|
|
}
|
|
|
|
// Commit pages. Returns whether pages were committed.
|
|
MOZ_MUST_USE static inline bool pages_commit(void* aAddr, size_t aSize) {
|
|
#ifdef XP_WIN
|
|
// The region starting at addr may have been allocated in multiple calls
|
|
// to VirtualAlloc and recycled, so committing the entire region in one
|
|
// go may not be valid. However, since we allocate at least a chunk at a
|
|
// time, we may touch any region in chunksized increments.
|
|
size_t pages_size = std::min(aSize, kChunkSize - GetChunkOffsetForPtr(aAddr));
|
|
while (aSize > 0) {
|
|
if (!VirtualAlloc(aAddr, pages_size, MEM_COMMIT, PAGE_READWRITE)) {
|
|
return false;
|
|
}
|
|
aAddr = (void*)((uintptr_t)aAddr + pages_size);
|
|
aSize -= pages_size;
|
|
pages_size = std::min(aSize, kChunkSize);
|
|
}
|
|
#else
|
|
if (mmap(aAddr, aSize, PROT_READ | PROT_WRITE,
|
|
MAP_FIXED | MAP_PRIVATE | MAP_ANON, -1, 0) == MAP_FAILED) {
|
|
return false;
|
|
}
|
|
MozTagAnonymousMemory(aAddr, aSize, "jemalloc");
|
|
#endif
|
|
return true;
|
|
}
|
|
|
|
static bool base_pages_alloc(size_t minsize) {
|
|
size_t csize;
|
|
size_t pminsize;
|
|
|
|
MOZ_ASSERT(minsize != 0);
|
|
csize = CHUNK_CEILING(minsize);
|
|
base_pages = chunk_alloc(csize, kChunkSize, true);
|
|
if (!base_pages) {
|
|
return true;
|
|
}
|
|
base_next_addr = base_pages;
|
|
base_past_addr = (void*)((uintptr_t)base_pages + csize);
|
|
// Leave enough pages for minsize committed, since otherwise they would
|
|
// have to be immediately recommitted.
|
|
pminsize = PAGE_CEILING(minsize);
|
|
base_next_decommitted = (void*)((uintptr_t)base_pages + pminsize);
|
|
if (pminsize < csize) {
|
|
pages_decommit(base_next_decommitted, csize - pminsize);
|
|
}
|
|
base_mapped += csize;
|
|
base_committed += pminsize;
|
|
|
|
return false;
|
|
}
|
|
|
|
static void* base_alloc(size_t aSize) {
|
|
void* ret;
|
|
size_t csize;
|
|
|
|
// Round size up to nearest multiple of the cacheline size.
|
|
csize = CACHELINE_CEILING(aSize);
|
|
|
|
MutexAutoLock lock(base_mtx);
|
|
// Make sure there's enough space for the allocation.
|
|
if ((uintptr_t)base_next_addr + csize > (uintptr_t)base_past_addr) {
|
|
if (base_pages_alloc(csize)) {
|
|
return nullptr;
|
|
}
|
|
}
|
|
// Allocate.
|
|
ret = base_next_addr;
|
|
base_next_addr = (void*)((uintptr_t)base_next_addr + csize);
|
|
// Make sure enough pages are committed for the new allocation.
|
|
if ((uintptr_t)base_next_addr > (uintptr_t)base_next_decommitted) {
|
|
void* pbase_next_addr = (void*)(PAGE_CEILING((uintptr_t)base_next_addr));
|
|
|
|
if (!pages_commit(
|
|
base_next_decommitted,
|
|
(uintptr_t)pbase_next_addr - (uintptr_t)base_next_decommitted)) {
|
|
return nullptr;
|
|
}
|
|
|
|
base_committed +=
|
|
(uintptr_t)pbase_next_addr - (uintptr_t)base_next_decommitted;
|
|
base_next_decommitted = pbase_next_addr;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void* base_calloc(size_t aNumber, size_t aSize) {
|
|
void* ret = base_alloc(aNumber * aSize);
|
|
if (ret) {
|
|
memset(ret, 0, aNumber * aSize);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static extent_node_t* base_node_alloc(void) {
|
|
extent_node_t* ret;
|
|
|
|
base_mtx.Lock();
|
|
if (base_nodes) {
|
|
ret = base_nodes;
|
|
base_nodes = *(extent_node_t**)ret;
|
|
base_mtx.Unlock();
|
|
} else {
|
|
base_mtx.Unlock();
|
|
ret = (extent_node_t*)base_alloc(sizeof(extent_node_t));
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void base_node_dealloc(extent_node_t* aNode) {
|
|
MutexAutoLock lock(base_mtx);
|
|
*(extent_node_t**)aNode = base_nodes;
|
|
base_nodes = aNode;
|
|
}
|
|
|
|
struct BaseNodeFreePolicy {
|
|
void operator()(extent_node_t* aPtr) { base_node_dealloc(aPtr); }
|
|
};
|
|
|
|
using UniqueBaseNode = UniquePtr<extent_node_t, BaseNodeFreePolicy>;
|
|
|
|
// End Utility functions/macros.
|
|
// ***************************************************************************
|
|
// Begin chunk management functions.
|
|
|
|
#ifdef XP_WIN
|
|
|
|
static void* pages_map(void* aAddr, size_t aSize) {
|
|
void* ret = nullptr;
|
|
ret = VirtualAlloc(aAddr, aSize, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
|
|
return ret;
|
|
}
|
|
|
|
static void pages_unmap(void* aAddr, size_t aSize) {
|
|
if (VirtualFree(aAddr, 0, MEM_RELEASE) == 0) {
|
|
_malloc_message(_getprogname(), ": (malloc) Error in VirtualFree()\n");
|
|
}
|
|
}
|
|
#else
|
|
|
|
static void pages_unmap(void* aAddr, size_t aSize) {
|
|
if (munmap(aAddr, aSize) == -1) {
|
|
char buf[64];
|
|
|
|
if (strerror_r(errno, buf, sizeof(buf)) == 0) {
|
|
_malloc_message(_getprogname(), ": (malloc) Error in munmap(): ", buf,
|
|
"\n");
|
|
}
|
|
}
|
|
}
|
|
|
|
static void* pages_map(void* aAddr, size_t aSize) {
|
|
void* ret;
|
|
# if defined(__ia64__) || \
|
|
(defined(__sparc__) && defined(__arch64__) && defined(__linux__))
|
|
// The JS engine assumes that all allocated pointers have their high 17 bits
|
|
// clear, which ia64's mmap doesn't support directly. However, we can emulate
|
|
// it by passing mmap an "addr" parameter with those bits clear. The mmap will
|
|
// return that address, or the nearest available memory above that address,
|
|
// providing a near-guarantee that those bits are clear. If they are not, we
|
|
// return nullptr below to indicate out-of-memory.
|
|
//
|
|
// The addr is chosen as 0x0000070000000000, which still allows about 120TB of
|
|
// virtual address space.
|
|
//
|
|
// See Bug 589735 for more information.
|
|
bool check_placement = true;
|
|
if (!aAddr) {
|
|
aAddr = (void*)0x0000070000000000;
|
|
check_placement = false;
|
|
}
|
|
# endif
|
|
|
|
# if defined(__sparc__) && defined(__arch64__) && defined(__linux__)
|
|
const uintptr_t start = 0x0000070000000000ULL;
|
|
const uintptr_t end = 0x0000800000000000ULL;
|
|
|
|
// Copied from js/src/gc/Memory.cpp and adapted for this source
|
|
uintptr_t hint;
|
|
void* region = MAP_FAILED;
|
|
for (hint = start; region == MAP_FAILED && hint + aSize <= end;
|
|
hint += kChunkSize) {
|
|
region = mmap((void*)hint, aSize, PROT_READ | PROT_WRITE,
|
|
MAP_PRIVATE | MAP_ANON, -1, 0);
|
|
if (region != MAP_FAILED) {
|
|
if (((size_t)region + (aSize - 1)) & 0xffff800000000000) {
|
|
if (munmap(region, aSize)) {
|
|
MOZ_ASSERT(errno == ENOMEM);
|
|
}
|
|
region = MAP_FAILED;
|
|
}
|
|
}
|
|
}
|
|
ret = region;
|
|
# else
|
|
// We don't use MAP_FIXED here, because it can cause the *replacement*
|
|
// of existing mappings, and we only want to create new mappings.
|
|
ret =
|
|
mmap(aAddr, aSize, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
|
|
MOZ_ASSERT(ret);
|
|
# endif
|
|
if (ret == MAP_FAILED) {
|
|
ret = nullptr;
|
|
}
|
|
# if defined(__ia64__) || \
|
|
(defined(__sparc__) && defined(__arch64__) && defined(__linux__))
|
|
// If the allocated memory doesn't have its upper 17 bits clear, consider it
|
|
// as out of memory.
|
|
else if ((long long)ret & 0xffff800000000000) {
|
|
munmap(ret, aSize);
|
|
ret = nullptr;
|
|
}
|
|
// If the caller requested a specific memory location, verify that's what mmap
|
|
// returned.
|
|
else if (check_placement && ret != aAddr) {
|
|
# else
|
|
else if (aAddr && ret != aAddr) {
|
|
# endif
|
|
// We succeeded in mapping memory, but not in the right place.
|
|
pages_unmap(ret, aSize);
|
|
ret = nullptr;
|
|
}
|
|
if (ret) {
|
|
MozTagAnonymousMemory(ret, aSize, "jemalloc");
|
|
}
|
|
|
|
# if defined(__ia64__) || \
|
|
(defined(__sparc__) && defined(__arch64__) && defined(__linux__))
|
|
MOZ_ASSERT(!ret || (!check_placement && ret) ||
|
|
(check_placement && ret == aAddr));
|
|
# else
|
|
MOZ_ASSERT(!ret || (!aAddr && ret != aAddr) || (aAddr && ret == aAddr));
|
|
# endif
|
|
return ret;
|
|
}
|
|
#endif
|
|
|
|
#ifdef XP_DARWIN
|
|
# define VM_COPY_MIN (gPageSize * 32)
|
|
static inline void pages_copy(void* dest, const void* src, size_t n) {
|
|
MOZ_ASSERT((void*)((uintptr_t)dest & ~gPageSizeMask) == dest);
|
|
MOZ_ASSERT(n >= VM_COPY_MIN);
|
|
MOZ_ASSERT((void*)((uintptr_t)src & ~gPageSizeMask) == src);
|
|
|
|
kern_return_t r = vm_copy(mach_task_self(), (vm_address_t)src, (vm_size_t)n,
|
|
(vm_address_t)dest);
|
|
if (r != KERN_SUCCESS) {
|
|
MOZ_CRASH("vm_copy() failed");
|
|
}
|
|
}
|
|
|
|
#endif
|
|
|
|
template <size_t Bits>
|
|
bool AddressRadixTree<Bits>::Init() {
|
|
mLock.Init();
|
|
mRoot = (void**)base_calloc(1 << kBitsAtLevel1, sizeof(void*));
|
|
return mRoot;
|
|
}
|
|
|
|
template <size_t Bits>
|
|
void** AddressRadixTree<Bits>::GetSlot(void* aKey, bool aCreate) {
|
|
uintptr_t key = reinterpret_cast<uintptr_t>(aKey);
|
|
uintptr_t subkey;
|
|
unsigned i, lshift, height, bits;
|
|
void** node;
|
|
void** child;
|
|
|
|
for (i = lshift = 0, height = kHeight, node = mRoot; i < height - 1;
|
|
i++, lshift += bits, node = child) {
|
|
bits = i ? kBitsPerLevel : kBitsAtLevel1;
|
|
subkey = (key << lshift) >> ((sizeof(void*) << 3) - bits);
|
|
child = (void**)node[subkey];
|
|
if (!child && aCreate) {
|
|
child = (void**)base_calloc(1 << kBitsPerLevel, sizeof(void*));
|
|
if (child) {
|
|
node[subkey] = child;
|
|
}
|
|
}
|
|
if (!child) {
|
|
return nullptr;
|
|
}
|
|
}
|
|
|
|
// node is a leaf, so it contains values rather than node
|
|
// pointers.
|
|
bits = i ? kBitsPerLevel : kBitsAtLevel1;
|
|
subkey = (key << lshift) >> ((sizeof(void*) << 3) - bits);
|
|
return &node[subkey];
|
|
}
|
|
|
|
template <size_t Bits>
|
|
void* AddressRadixTree<Bits>::Get(void* aKey) {
|
|
void* ret = nullptr;
|
|
|
|
void** slot = GetSlot(aKey);
|
|
|
|
if (slot) {
|
|
ret = *slot;
|
|
}
|
|
#ifdef MOZ_DEBUG
|
|
MutexAutoLock lock(mLock);
|
|
|
|
// Suppose that it were possible for a jemalloc-allocated chunk to be
|
|
// munmap()ped, followed by a different allocator in another thread re-using
|
|
// overlapping virtual memory, all without invalidating the cached rtree
|
|
// value. The result would be a false positive (the rtree would claim that
|
|
// jemalloc owns memory that it had actually discarded). I don't think this
|
|
// scenario is possible, but the following assertion is a prudent sanity
|
|
// check.
|
|
if (!slot) {
|
|
// In case a slot has been created in the meantime.
|
|
slot = GetSlot(aKey);
|
|
}
|
|
if (slot) {
|
|
// The MutexAutoLock above should act as a memory barrier, forcing
|
|
// the compiler to emit a new read instruction for *slot.
|
|
MOZ_ASSERT(ret == *slot);
|
|
} else {
|
|
MOZ_ASSERT(ret == nullptr);
|
|
}
|
|
#endif
|
|
return ret;
|
|
}
|
|
|
|
template <size_t Bits>
|
|
bool AddressRadixTree<Bits>::Set(void* aKey, void* aValue) {
|
|
MutexAutoLock lock(mLock);
|
|
void** slot = GetSlot(aKey, /* create = */ true);
|
|
if (slot) {
|
|
*slot = aValue;
|
|
}
|
|
return slot;
|
|
}
|
|
|
|
// pages_trim, chunk_alloc_mmap_slow and chunk_alloc_mmap were cherry-picked
|
|
// from upstream jemalloc 3.4.1 to fix Mozilla bug 956501.
|
|
|
|
// Return the offset between a and the nearest aligned address at or below a.
|
|
#define ALIGNMENT_ADDR2OFFSET(a, alignment) \
|
|
((size_t)((uintptr_t)(a) & (alignment - 1)))
|
|
|
|
// Return the smallest alignment multiple that is >= s.
|
|
#define ALIGNMENT_CEILING(s, alignment) \
|
|
(((s) + (alignment - 1)) & (~(alignment - 1)))
|
|
|
|
static void* pages_trim(void* addr, size_t alloc_size, size_t leadsize,
|
|
size_t size) {
|
|
void* ret = (void*)((uintptr_t)addr + leadsize);
|
|
|
|
MOZ_ASSERT(alloc_size >= leadsize + size);
|
|
#ifdef XP_WIN
|
|
{
|
|
void* new_addr;
|
|
|
|
pages_unmap(addr, alloc_size);
|
|
new_addr = pages_map(ret, size);
|
|
if (new_addr == ret) {
|
|
return ret;
|
|
}
|
|
if (new_addr) {
|
|
pages_unmap(new_addr, size);
|
|
}
|
|
return nullptr;
|
|
}
|
|
#else
|
|
{
|
|
size_t trailsize = alloc_size - leadsize - size;
|
|
|
|
if (leadsize != 0) {
|
|
pages_unmap(addr, leadsize);
|
|
}
|
|
if (trailsize != 0) {
|
|
pages_unmap((void*)((uintptr_t)ret + size), trailsize);
|
|
}
|
|
return ret;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
static void* chunk_alloc_mmap_slow(size_t size, size_t alignment) {
|
|
void *ret, *pages;
|
|
size_t alloc_size, leadsize;
|
|
|
|
alloc_size = size + alignment - gPageSize;
|
|
// Beware size_t wrap-around.
|
|
if (alloc_size < size) {
|
|
return nullptr;
|
|
}
|
|
do {
|
|
pages = pages_map(nullptr, alloc_size);
|
|
if (!pages) {
|
|
return nullptr;
|
|
}
|
|
leadsize =
|
|
ALIGNMENT_CEILING((uintptr_t)pages, alignment) - (uintptr_t)pages;
|
|
ret = pages_trim(pages, alloc_size, leadsize, size);
|
|
} while (!ret);
|
|
|
|
MOZ_ASSERT(ret);
|
|
return ret;
|
|
}
|
|
|
|
static void* chunk_alloc_mmap(size_t size, size_t alignment) {
|
|
void* ret;
|
|
size_t offset;
|
|
|
|
// Ideally, there would be a way to specify alignment to mmap() (like
|
|
// NetBSD has), but in the absence of such a feature, we have to work
|
|
// hard to efficiently create aligned mappings. The reliable, but
|
|
// slow method is to create a mapping that is over-sized, then trim the
|
|
// excess. However, that always results in one or two calls to
|
|
// pages_unmap().
|
|
//
|
|
// Optimistically try mapping precisely the right amount before falling
|
|
// back to the slow method, with the expectation that the optimistic
|
|
// approach works most of the time.
|
|
ret = pages_map(nullptr, size);
|
|
if (!ret) {
|
|
return nullptr;
|
|
}
|
|
offset = ALIGNMENT_ADDR2OFFSET(ret, alignment);
|
|
if (offset != 0) {
|
|
pages_unmap(ret, size);
|
|
return chunk_alloc_mmap_slow(size, alignment);
|
|
}
|
|
|
|
MOZ_ASSERT(ret);
|
|
return ret;
|
|
}
|
|
|
|
// Purge and release the pages in the chunk of length `length` at `addr` to
|
|
// the OS.
|
|
// Returns whether the pages are guaranteed to be full of zeroes when the
|
|
// function returns.
|
|
// The force_zero argument explicitly requests that the memory is guaranteed
|
|
// to be full of zeroes when the function returns.
|
|
static bool pages_purge(void* addr, size_t length, bool force_zero) {
|
|
pages_decommit(addr, length);
|
|
return true;
|
|
}
|
|
|
|
static void* chunk_recycle(size_t aSize, size_t aAlignment, bool* aZeroed) {
|
|
extent_node_t key;
|
|
|
|
size_t alloc_size = aSize + aAlignment - kChunkSize;
|
|
// Beware size_t wrap-around.
|
|
if (alloc_size < aSize) {
|
|
return nullptr;
|
|
}
|
|
key.mAddr = nullptr;
|
|
key.mSize = alloc_size;
|
|
chunks_mtx.Lock();
|
|
extent_node_t* node = gChunksBySize.SearchOrNext(&key);
|
|
if (!node) {
|
|
chunks_mtx.Unlock();
|
|
return nullptr;
|
|
}
|
|
size_t leadsize = ALIGNMENT_CEILING((uintptr_t)node->mAddr, aAlignment) -
|
|
(uintptr_t)node->mAddr;
|
|
MOZ_ASSERT(node->mSize >= leadsize + aSize);
|
|
size_t trailsize = node->mSize - leadsize - aSize;
|
|
void* ret = (void*)((uintptr_t)node->mAddr + leadsize);
|
|
ChunkType chunk_type = node->mChunkType;
|
|
if (aZeroed) {
|
|
*aZeroed = (chunk_type == ZEROED_CHUNK);
|
|
}
|
|
// Remove node from the tree.
|
|
gChunksBySize.Remove(node);
|
|
gChunksByAddress.Remove(node);
|
|
if (leadsize != 0) {
|
|
// Insert the leading space as a smaller chunk.
|
|
node->mSize = leadsize;
|
|
gChunksBySize.Insert(node);
|
|
gChunksByAddress.Insert(node);
|
|
node = nullptr;
|
|
}
|
|
if (trailsize != 0) {
|
|
// Insert the trailing space as a smaller chunk.
|
|
if (!node) {
|
|
// An additional node is required, but
|
|
// base_node_alloc() can cause a new base chunk to be
|
|
// allocated. Drop chunks_mtx in order to avoid
|
|
// deadlock, and if node allocation fails, deallocate
|
|
// the result before returning an error.
|
|
chunks_mtx.Unlock();
|
|
node = base_node_alloc();
|
|
if (!node) {
|
|
chunk_dealloc(ret, aSize, chunk_type);
|
|
return nullptr;
|
|
}
|
|
chunks_mtx.Lock();
|
|
}
|
|
node->mAddr = (void*)((uintptr_t)(ret) + aSize);
|
|
node->mSize = trailsize;
|
|
node->mChunkType = chunk_type;
|
|
gChunksBySize.Insert(node);
|
|
gChunksByAddress.Insert(node);
|
|
node = nullptr;
|
|
}
|
|
|
|
gRecycledSize -= aSize;
|
|
|
|
chunks_mtx.Unlock();
|
|
|
|
if (node) {
|
|
base_node_dealloc(node);
|
|
}
|
|
if (!pages_commit(ret, aSize)) {
|
|
return nullptr;
|
|
}
|
|
// pages_commit is guaranteed to zero the chunk.
|
|
if (aZeroed) {
|
|
*aZeroed = true;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
#ifdef XP_WIN
|
|
// On Windows, calls to VirtualAlloc and VirtualFree must be matched, making it
|
|
// awkward to recycle allocations of varying sizes. Therefore we only allow
|
|
// recycling when the size equals the chunksize, unless deallocation is entirely
|
|
// disabled.
|
|
# define CAN_RECYCLE(size) (size == kChunkSize)
|
|
#else
|
|
# define CAN_RECYCLE(size) true
|
|
#endif
|
|
|
|
// Allocates `size` bytes of system memory aligned for `alignment`.
|
|
// `base` indicates whether the memory will be used for the base allocator
|
|
// (e.g. base_alloc).
|
|
// `zeroed` is an outvalue that returns whether the allocated memory is
|
|
// guaranteed to be full of zeroes. It can be omitted when the caller doesn't
|
|
// care about the result.
|
|
static void* chunk_alloc(size_t aSize, size_t aAlignment, bool aBase,
|
|
bool* aZeroed) {
|
|
void* ret = nullptr;
|
|
|
|
MOZ_ASSERT(aSize != 0);
|
|
MOZ_ASSERT((aSize & kChunkSizeMask) == 0);
|
|
MOZ_ASSERT(aAlignment != 0);
|
|
MOZ_ASSERT((aAlignment & kChunkSizeMask) == 0);
|
|
|
|
// Base allocations can't be fulfilled by recycling because of
|
|
// possible deadlock or infinite recursion.
|
|
if (CAN_RECYCLE(aSize) && !aBase) {
|
|
ret = chunk_recycle(aSize, aAlignment, aZeroed);
|
|
}
|
|
if (!ret) {
|
|
ret = chunk_alloc_mmap(aSize, aAlignment);
|
|
if (aZeroed) {
|
|
*aZeroed = true;
|
|
}
|
|
}
|
|
if (ret && !aBase) {
|
|
if (!gChunkRTree.Set(ret, ret)) {
|
|
chunk_dealloc(ret, aSize, UNKNOWN_CHUNK);
|
|
return nullptr;
|
|
}
|
|
}
|
|
|
|
MOZ_ASSERT(GetChunkOffsetForPtr(ret) == 0);
|
|
return ret;
|
|
}
|
|
|
|
static void chunk_ensure_zero(void* aPtr, size_t aSize, bool aZeroed) {
|
|
if (aZeroed == false) {
|
|
memset(aPtr, 0, aSize);
|
|
}
|
|
#ifdef MOZ_DEBUG
|
|
else {
|
|
size_t i;
|
|
size_t* p = (size_t*)(uintptr_t)aPtr;
|
|
|
|
for (i = 0; i < aSize / sizeof(size_t); i++) {
|
|
MOZ_ASSERT(p[i] == 0);
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
static void chunk_record(void* aChunk, size_t aSize, ChunkType aType) {
|
|
extent_node_t key;
|
|
|
|
if (aType != ZEROED_CHUNK) {
|
|
if (pages_purge(aChunk, aSize, aType == HUGE_CHUNK)) {
|
|
aType = ZEROED_CHUNK;
|
|
}
|
|
}
|
|
|
|
// Allocate a node before acquiring chunks_mtx even though it might not
|
|
// be needed, because base_node_alloc() may cause a new base chunk to
|
|
// be allocated, which could cause deadlock if chunks_mtx were already
|
|
// held.
|
|
UniqueBaseNode xnode(base_node_alloc());
|
|
// Use xprev to implement conditional deferred deallocation of prev.
|
|
UniqueBaseNode xprev;
|
|
|
|
// RAII deallocates xnode and xprev defined above after unlocking
|
|
// in order to avoid potential dead-locks
|
|
MutexAutoLock lock(chunks_mtx);
|
|
key.mAddr = (void*)((uintptr_t)aChunk + aSize);
|
|
extent_node_t* node = gChunksByAddress.SearchOrNext(&key);
|
|
// Try to coalesce forward.
|
|
if (node && node->mAddr == key.mAddr) {
|
|
// Coalesce chunk with the following address range. This does
|
|
// not change the position within gChunksByAddress, so only
|
|
// remove/insert from/into gChunksBySize.
|
|
gChunksBySize.Remove(node);
|
|
node->mAddr = aChunk;
|
|
node->mSize += aSize;
|
|
if (node->mChunkType != aType) {
|
|
node->mChunkType = RECYCLED_CHUNK;
|
|
}
|
|
gChunksBySize.Insert(node);
|
|
} else {
|
|
// Coalescing forward failed, so insert a new node.
|
|
if (!xnode) {
|
|
// base_node_alloc() failed, which is an exceedingly
|
|
// unlikely failure. Leak chunk; its pages have
|
|
// already been purged, so this is only a virtual
|
|
// memory leak.
|
|
return;
|
|
}
|
|
node = xnode.release();
|
|
node->mAddr = aChunk;
|
|
node->mSize = aSize;
|
|
node->mChunkType = aType;
|
|
gChunksByAddress.Insert(node);
|
|
gChunksBySize.Insert(node);
|
|
}
|
|
|
|
// Try to coalesce backward.
|
|
extent_node_t* prev = gChunksByAddress.Prev(node);
|
|
if (prev && (void*)((uintptr_t)prev->mAddr + prev->mSize) == aChunk) {
|
|
// Coalesce chunk with the previous address range. This does
|
|
// not change the position within gChunksByAddress, so only
|
|
// remove/insert node from/into gChunksBySize.
|
|
gChunksBySize.Remove(prev);
|
|
gChunksByAddress.Remove(prev);
|
|
|
|
gChunksBySize.Remove(node);
|
|
node->mAddr = prev->mAddr;
|
|
node->mSize += prev->mSize;
|
|
if (node->mChunkType != prev->mChunkType) {
|
|
node->mChunkType = RECYCLED_CHUNK;
|
|
}
|
|
gChunksBySize.Insert(node);
|
|
|
|
xprev.reset(prev);
|
|
}
|
|
|
|
gRecycledSize += aSize;
|
|
}
|
|
|
|
static void chunk_dealloc(void* aChunk, size_t aSize, ChunkType aType) {
|
|
MOZ_ASSERT(aChunk);
|
|
MOZ_ASSERT(GetChunkOffsetForPtr(aChunk) == 0);
|
|
MOZ_ASSERT(aSize != 0);
|
|
MOZ_ASSERT((aSize & kChunkSizeMask) == 0);
|
|
|
|
gChunkRTree.Unset(aChunk);
|
|
|
|
if (CAN_RECYCLE(aSize)) {
|
|
size_t recycled_so_far = gRecycledSize;
|
|
// In case some race condition put us above the limit.
|
|
if (recycled_so_far < gRecycleLimit) {
|
|
size_t recycle_remaining = gRecycleLimit - recycled_so_far;
|
|
size_t to_recycle;
|
|
if (aSize > recycle_remaining) {
|
|
to_recycle = recycle_remaining;
|
|
// Drop pages that would overflow the recycle limit
|
|
pages_trim(aChunk, aSize, 0, to_recycle);
|
|
} else {
|
|
to_recycle = aSize;
|
|
}
|
|
chunk_record(aChunk, to_recycle, aType);
|
|
return;
|
|
}
|
|
}
|
|
|
|
pages_unmap(aChunk, aSize);
|
|
}
|
|
|
|
#undef CAN_RECYCLE
|
|
|
|
// End chunk management functions.
|
|
// ***************************************************************************
|
|
// Begin arena.
|
|
|
|
static inline arena_t* thread_local_arena(bool enabled) {
|
|
arena_t* arena;
|
|
|
|
if (enabled) {
|
|
// The arena will essentially be leaked if this function is
|
|
// called with `false`, but it doesn't matter at the moment.
|
|
// because in practice nothing actually calls this function
|
|
// with `false`, except maybe at shutdown.
|
|
arena =
|
|
gArenas.CreateArena(/* IsPrivate = */ false, /* Params = */ nullptr);
|
|
} else {
|
|
arena = gArenas.GetDefault();
|
|
}
|
|
thread_arena.set(arena);
|
|
return arena;
|
|
}
|
|
|
|
template <>
|
|
inline void MozJemalloc::jemalloc_thread_local_arena(bool aEnabled) {
|
|
if (malloc_init()) {
|
|
thread_local_arena(aEnabled);
|
|
}
|
|
}
|
|
|
|
// Choose an arena based on a per-thread value.
|
|
static inline arena_t* choose_arena(size_t size) {
|
|
arena_t* ret = nullptr;
|
|
|
|
// We can only use TLS if this is a PIC library, since for the static
|
|
// library version, libc's malloc is used by TLS allocation, which
|
|
// introduces a bootstrapping issue.
|
|
|
|
if (size > kMaxQuantumClass) {
|
|
// Force the default arena for larger allocations.
|
|
ret = gArenas.GetDefault();
|
|
} else {
|
|
// Check TLS to see if our thread has requested a pinned arena.
|
|
ret = thread_arena.get();
|
|
if (!ret) {
|
|
// Nothing in TLS. Pin this thread to the default arena.
|
|
ret = thread_local_arena(false);
|
|
}
|
|
}
|
|
|
|
MOZ_DIAGNOSTIC_ASSERT(ret);
|
|
return ret;
|
|
}
|
|
|
|
static inline void* arena_run_reg_alloc(arena_run_t* run, arena_bin_t* bin) {
|
|
void* ret;
|
|
unsigned i, mask, bit, regind;
|
|
|
|
MOZ_DIAGNOSTIC_ASSERT(run->mMagic == ARENA_RUN_MAGIC);
|
|
MOZ_ASSERT(run->mRegionsMinElement < bin->mRunNumRegionsMask);
|
|
|
|
// Move the first check outside the loop, so that run->mRegionsMinElement can
|
|
// be updated unconditionally, without the possibility of updating it
|
|
// multiple times.
|
|
i = run->mRegionsMinElement;
|
|
mask = run->mRegionsMask[i];
|
|
if (mask != 0) {
|
|
// Usable allocation found.
|
|
bit = CountTrailingZeroes32(mask);
|
|
|
|
regind = ((i << (LOG2(sizeof(int)) + 3)) + bit);
|
|
MOZ_ASSERT(regind < bin->mRunNumRegions);
|
|
ret = (void*)(((uintptr_t)run) + bin->mRunFirstRegionOffset +
|
|
(bin->mSizeClass * regind));
|
|
|
|
// Clear bit.
|
|
mask ^= (1U << bit);
|
|
run->mRegionsMask[i] = mask;
|
|
|
|
return ret;
|
|
}
|
|
|
|
for (i++; i < bin->mRunNumRegionsMask; i++) {
|
|
mask = run->mRegionsMask[i];
|
|
if (mask != 0) {
|
|
// Usable allocation found.
|
|
bit = CountTrailingZeroes32(mask);
|
|
|
|
regind = ((i << (LOG2(sizeof(int)) + 3)) + bit);
|
|
MOZ_ASSERT(regind < bin->mRunNumRegions);
|
|
ret = (void*)(((uintptr_t)run) + bin->mRunFirstRegionOffset +
|
|
(bin->mSizeClass * regind));
|
|
|
|
// Clear bit.
|
|
mask ^= (1U << bit);
|
|
run->mRegionsMask[i] = mask;
|
|
|
|
// Make a note that nothing before this element
|
|
// contains a free region.
|
|
run->mRegionsMinElement = i; // Low payoff: + (mask == 0);
|
|
|
|
return ret;
|
|
}
|
|
}
|
|
// Not reached.
|
|
MOZ_DIAGNOSTIC_ASSERT(0);
|
|
return nullptr;
|
|
}
|
|
|
|
static inline void arena_run_reg_dalloc(arena_run_t* run, arena_bin_t* bin,
|
|
void* ptr, size_t size) {
|
|
// To divide by a number D that is not a power of two we multiply
|
|
// by (2^21 / D) and then right shift by 21 positions.
|
|
//
|
|
// X / D
|
|
//
|
|
// becomes
|
|
//
|
|
// (X * size_invs[(D / kQuantum) - 3]) >> SIZE_INV_SHIFT
|
|
|
|
#define SIZE_INV_SHIFT 21
|
|
#define SIZE_INV(s) (((1U << SIZE_INV_SHIFT) / (s * kQuantum)) + 1)
|
|
// clang-format off
|
|
static const unsigned size_invs[] = {
|
|
SIZE_INV(3),
|
|
SIZE_INV(4), SIZE_INV(5), SIZE_INV(6), SIZE_INV(7),
|
|
SIZE_INV(8), SIZE_INV(9), SIZE_INV(10), SIZE_INV(11),
|
|
SIZE_INV(12),SIZE_INV(13), SIZE_INV(14), SIZE_INV(15),
|
|
SIZE_INV(16),SIZE_INV(17), SIZE_INV(18), SIZE_INV(19),
|
|
SIZE_INV(20),SIZE_INV(21), SIZE_INV(22), SIZE_INV(23),
|
|
SIZE_INV(24),SIZE_INV(25), SIZE_INV(26), SIZE_INV(27),
|
|
SIZE_INV(28),SIZE_INV(29), SIZE_INV(30), SIZE_INV(31)
|
|
};
|
|
// clang-format on
|
|
unsigned diff, regind, elm, bit;
|
|
|
|
MOZ_DIAGNOSTIC_ASSERT(run->mMagic == ARENA_RUN_MAGIC);
|
|
static_assert(
|
|
((sizeof(size_invs)) / sizeof(unsigned)) + 3 >= kNumQuantumClasses,
|
|
"size_invs doesn't have enough values");
|
|
|
|
// Avoid doing division with a variable divisor if possible. Using
|
|
// actual division here can reduce allocator throughput by over 20%!
|
|
diff =
|
|
(unsigned)((uintptr_t)ptr - (uintptr_t)run - bin->mRunFirstRegionOffset);
|
|
if (mozilla::IsPowerOfTwo(size)) {
|
|
regind = diff >> FloorLog2(size);
|
|
} else if (size <= ((sizeof(size_invs) / sizeof(unsigned)) * kQuantum) + 2) {
|
|
regind = size_invs[(size / kQuantum) - 3] * diff;
|
|
regind >>= SIZE_INV_SHIFT;
|
|
} else {
|
|
// size_invs isn't large enough to handle this size class, so
|
|
// calculate regind using actual division. This only happens
|
|
// if the user increases small_max via the 'S' runtime
|
|
// configuration option.
|
|
regind = diff / size;
|
|
};
|
|
MOZ_DIAGNOSTIC_ASSERT(diff == regind * size);
|
|
MOZ_DIAGNOSTIC_ASSERT(regind < bin->mRunNumRegions);
|
|
|
|
elm = regind >> (LOG2(sizeof(int)) + 3);
|
|
if (elm < run->mRegionsMinElement) {
|
|
run->mRegionsMinElement = elm;
|
|
}
|
|
bit = regind - (elm << (LOG2(sizeof(int)) + 3));
|
|
MOZ_RELEASE_ASSERT((run->mRegionsMask[elm] & (1U << bit)) == 0,
|
|
"Double-free?");
|
|
run->mRegionsMask[elm] |= (1U << bit);
|
|
#undef SIZE_INV
|
|
#undef SIZE_INV_SHIFT
|
|
}
|
|
|
|
bool arena_t::SplitRun(arena_run_t* aRun, size_t aSize, bool aLarge,
|
|
bool aZero) {
|
|
arena_chunk_t* chunk;
|
|
size_t old_ndirty, run_ind, total_pages, need_pages, rem_pages, i;
|
|
|
|
chunk = GetChunkForPtr(aRun);
|
|
old_ndirty = chunk->ndirty;
|
|
run_ind = (unsigned)((uintptr_t(aRun) - uintptr_t(chunk)) >> gPageSize2Pow);
|
|
total_pages = (chunk->map[run_ind].bits & ~gPageSizeMask) >> gPageSize2Pow;
|
|
need_pages = (aSize >> gPageSize2Pow);
|
|
MOZ_ASSERT(need_pages > 0);
|
|
MOZ_ASSERT(need_pages <= total_pages);
|
|
rem_pages = total_pages - need_pages;
|
|
|
|
for (i = 0; i < need_pages; i++) {
|
|
// Commit decommitted pages if necessary. If a decommitted
|
|
// page is encountered, commit all needed adjacent decommitted
|
|
// pages in one operation, in order to reduce system call
|
|
// overhead.
|
|
if (chunk->map[run_ind + i].bits & CHUNK_MAP_MADVISED_OR_DECOMMITTED) {
|
|
size_t j;
|
|
|
|
// Advance i+j to just past the index of the last page
|
|
// to commit. Clear CHUNK_MAP_DECOMMITTED and
|
|
// CHUNK_MAP_MADVISED along the way.
|
|
for (j = 0; i + j < need_pages && (chunk->map[run_ind + i + j].bits &
|
|
CHUNK_MAP_MADVISED_OR_DECOMMITTED);
|
|
j++) {
|
|
// DECOMMITTED and MADVISED are mutually exclusive.
|
|
MOZ_ASSERT(!(chunk->map[run_ind + i + j].bits & CHUNK_MAP_DECOMMITTED &&
|
|
chunk->map[run_ind + i + j].bits & CHUNK_MAP_MADVISED));
|
|
|
|
chunk->map[run_ind + i + j].bits &= ~CHUNK_MAP_MADVISED_OR_DECOMMITTED;
|
|
}
|
|
|
|
#ifdef MALLOC_DECOMMIT
|
|
bool committed = pages_commit(
|
|
(void*)(uintptr_t(chunk) + ((run_ind + i) << gPageSize2Pow)),
|
|
j << gPageSize2Pow);
|
|
// pages_commit zeroes pages, so mark them as such if it succeeded.
|
|
// That's checked further below to avoid manually zeroing the pages.
|
|
for (size_t k = 0; k < j; k++) {
|
|
chunk->map[run_ind + i + k].bits |=
|
|
committed ? CHUNK_MAP_ZEROED : CHUNK_MAP_DECOMMITTED;
|
|
}
|
|
if (!committed) {
|
|
return false;
|
|
}
|
|
#endif
|
|
|
|
mStats.committed += j;
|
|
}
|
|
}
|
|
|
|
mRunsAvail.Remove(&chunk->map[run_ind]);
|
|
|
|
// Keep track of trailing unused pages for later use.
|
|
if (rem_pages > 0) {
|
|
chunk->map[run_ind + need_pages].bits =
|
|
(rem_pages << gPageSize2Pow) |
|
|
(chunk->map[run_ind + need_pages].bits & gPageSizeMask);
|
|
chunk->map[run_ind + total_pages - 1].bits =
|
|
(rem_pages << gPageSize2Pow) |
|
|
(chunk->map[run_ind + total_pages - 1].bits & gPageSizeMask);
|
|
mRunsAvail.Insert(&chunk->map[run_ind + need_pages]);
|
|
}
|
|
|
|
for (i = 0; i < need_pages; i++) {
|
|
// Zero if necessary.
|
|
if (aZero) {
|
|
if ((chunk->map[run_ind + i].bits & CHUNK_MAP_ZEROED) == 0) {
|
|
memset((void*)(uintptr_t(chunk) + ((run_ind + i) << gPageSize2Pow)), 0,
|
|
gPageSize);
|
|
// CHUNK_MAP_ZEROED is cleared below.
|
|
}
|
|
}
|
|
|
|
// Update dirty page accounting.
|
|
if (chunk->map[run_ind + i].bits & CHUNK_MAP_DIRTY) {
|
|
chunk->ndirty--;
|
|
mNumDirty--;
|
|
// CHUNK_MAP_DIRTY is cleared below.
|
|
}
|
|
|
|
// Initialize the chunk map.
|
|
if (aLarge) {
|
|
chunk->map[run_ind + i].bits = CHUNK_MAP_LARGE | CHUNK_MAP_ALLOCATED;
|
|
} else {
|
|
chunk->map[run_ind + i].bits = size_t(aRun) | CHUNK_MAP_ALLOCATED;
|
|
}
|
|
}
|
|
|
|
// Set the run size only in the first element for large runs. This is
|
|
// primarily a debugging aid, since the lack of size info for trailing
|
|
// pages only matters if the application tries to operate on an
|
|
// interior pointer.
|
|
if (aLarge) {
|
|
chunk->map[run_ind].bits |= aSize;
|
|
}
|
|
|
|
if (chunk->ndirty == 0 && old_ndirty > 0) {
|
|
mChunksDirty.Remove(chunk);
|
|
}
|
|
return true;
|
|
}
|
|
|
|
void arena_t::InitChunk(arena_chunk_t* aChunk, bool aZeroed) {
|
|
size_t i;
|
|
// WARNING: The following relies on !aZeroed meaning "used to be an arena
|
|
// chunk".
|
|
// When the chunk we're initializating as an arena chunk is zeroed, we
|
|
// mark all runs are decommitted and zeroed.
|
|
// When it is not, which we can assume means it's a recycled arena chunk,
|
|
// all it can contain is an arena chunk header (which we're overwriting),
|
|
// and zeroed or poisoned memory (because a recycled arena chunk will
|
|
// have been emptied before being recycled). In that case, we can get
|
|
// away with reusing the chunk as-is, marking all runs as madvised.
|
|
|
|
size_t flags =
|
|
aZeroed ? CHUNK_MAP_DECOMMITTED | CHUNK_MAP_ZEROED : CHUNK_MAP_MADVISED;
|
|
|
|
mStats.mapped += kChunkSize;
|
|
|
|
aChunk->arena = this;
|
|
|
|
// Claim that no pages are in use, since the header is merely overhead.
|
|
aChunk->ndirty = 0;
|
|
|
|
// Initialize the map to contain one maximal free untouched run.
|
|
#ifdef MALLOC_DECOMMIT
|
|
arena_run_t* run = (arena_run_t*)(uintptr_t(aChunk) +
|
|
(gChunkHeaderNumPages << gPageSize2Pow));
|
|
#endif
|
|
|
|
for (i = 0; i < gChunkHeaderNumPages; i++) {
|
|
aChunk->map[i].bits = 0;
|
|
}
|
|
aChunk->map[i].bits = gMaxLargeClass | flags;
|
|
for (i++; i < gChunkNumPages - 2; i++) {
|
|
aChunk->map[i].bits = flags;
|
|
}
|
|
aChunk->map[gChunkNumPages - 2].bits = gMaxLargeClass | flags;
|
|
// Mark the guard page as decommited.
|
|
aChunk->map[gChunkNumPages - 1].bits = CHUNK_MAP_DECOMMITTED;
|
|
|
|
#ifdef MALLOC_DECOMMIT
|
|
// Start out decommitted, in order to force a closer correspondence
|
|
// between dirty pages and committed untouched pages.
|
|
pages_decommit(run, gMaxLargeClass + gPageSize);
|
|
#else
|
|
// Only decommit the last page as a guard.
|
|
pages_decommit((void*)(uintptr_t(aChunk) + kChunkSize - gPageSize),
|
|
gPageSize);
|
|
#endif
|
|
mStats.committed += gChunkHeaderNumPages;
|
|
|
|
// Insert the run into the tree of available runs.
|
|
mRunsAvail.Insert(&aChunk->map[gChunkHeaderNumPages]);
|
|
|
|
#ifdef MALLOC_DOUBLE_PURGE
|
|
new (&aChunk->chunks_madvised_elem) DoublyLinkedListElement<arena_chunk_t>();
|
|
#endif
|
|
}
|
|
|
|
void arena_t::DeallocChunk(arena_chunk_t* aChunk) {
|
|
if (mSpare) {
|
|
if (mSpare->ndirty > 0) {
|
|
aChunk->arena->mChunksDirty.Remove(mSpare);
|
|
mNumDirty -= mSpare->ndirty;
|
|
mStats.committed -= mSpare->ndirty;
|
|
}
|
|
|
|
#ifdef MALLOC_DOUBLE_PURGE
|
|
if (mChunksMAdvised.ElementProbablyInList(mSpare)) {
|
|
mChunksMAdvised.remove(mSpare);
|
|
}
|
|
#endif
|
|
|
|
chunk_dealloc((void*)mSpare, kChunkSize, ARENA_CHUNK);
|
|
mStats.mapped -= kChunkSize;
|
|
mStats.committed -= gChunkHeaderNumPages;
|
|
}
|
|
|
|
// Remove run from the tree of available runs, so that the arena does not use
|
|
// it. Dirty page flushing only uses the tree of dirty chunks, so leaving this
|
|
// chunk in the chunks_* trees is sufficient for that purpose.
|
|
mRunsAvail.Remove(&aChunk->map[gChunkHeaderNumPages]);
|
|
|
|
mSpare = aChunk;
|
|
}
|
|
|
|
arena_run_t* arena_t::AllocRun(size_t aSize, bool aLarge, bool aZero) {
|
|
arena_run_t* run;
|
|
arena_chunk_map_t* mapelm;
|
|
arena_chunk_map_t key;
|
|
|
|
MOZ_ASSERT(aSize <= gMaxLargeClass);
|
|
MOZ_ASSERT((aSize & gPageSizeMask) == 0);
|
|
|
|
// Search the arena's chunks for the lowest best fit.
|
|
key.bits = aSize | CHUNK_MAP_KEY;
|
|
mapelm = mRunsAvail.SearchOrNext(&key);
|
|
if (mapelm) {
|
|
arena_chunk_t* chunk = GetChunkForPtr(mapelm);
|
|
size_t pageind =
|
|
(uintptr_t(mapelm) - uintptr_t(chunk->map)) / sizeof(arena_chunk_map_t);
|
|
|
|
run = (arena_run_t*)(uintptr_t(chunk) + (pageind << gPageSize2Pow));
|
|
} else if (mSpare) {
|
|
// Use the spare.
|
|
arena_chunk_t* chunk = mSpare;
|
|
mSpare = nullptr;
|
|
run = (arena_run_t*)(uintptr_t(chunk) +
|
|
(gChunkHeaderNumPages << gPageSize2Pow));
|
|
// Insert the run into the tree of available runs.
|
|
mRunsAvail.Insert(&chunk->map[gChunkHeaderNumPages]);
|
|
} else {
|
|
// No usable runs. Create a new chunk from which to allocate
|
|
// the run.
|
|
bool zeroed;
|
|
arena_chunk_t* chunk =
|
|
(arena_chunk_t*)chunk_alloc(kChunkSize, kChunkSize, false, &zeroed);
|
|
if (!chunk) {
|
|
return nullptr;
|
|
}
|
|
|
|
InitChunk(chunk, zeroed);
|
|
run = (arena_run_t*)(uintptr_t(chunk) +
|
|
(gChunkHeaderNumPages << gPageSize2Pow));
|
|
}
|
|
// Update page map.
|
|
return SplitRun(run, aSize, aLarge, aZero) ? run : nullptr;
|
|
}
|
|
|
|
void arena_t::Purge(bool aAll) {
|
|
arena_chunk_t* chunk;
|
|
size_t i, npages;
|
|
// If all is set purge all dirty pages.
|
|
size_t dirty_max = aAll ? 1 : mMaxDirty;
|
|
#ifdef MOZ_DEBUG
|
|
size_t ndirty = 0;
|
|
for (auto chunk : mChunksDirty.iter()) {
|
|
ndirty += chunk->ndirty;
|
|
}
|
|
MOZ_ASSERT(ndirty == mNumDirty);
|
|
#endif
|
|
MOZ_DIAGNOSTIC_ASSERT(aAll || (mNumDirty > mMaxDirty));
|
|
|
|
// Iterate downward through chunks until enough dirty memory has been
|
|
// purged. Terminate as soon as possible in order to minimize the
|
|
// number of system calls, even if a chunk has only been partially
|
|
// purged.
|
|
while (mNumDirty > (dirty_max >> 1)) {
|
|
#ifdef MALLOC_DOUBLE_PURGE
|
|
bool madvised = false;
|
|
#endif
|
|
chunk = mChunksDirty.Last();
|
|
MOZ_DIAGNOSTIC_ASSERT(chunk);
|
|
// Last page is DECOMMITTED as a guard page.
|
|
MOZ_ASSERT((chunk->map[gChunkNumPages - 1].bits & CHUNK_MAP_DECOMMITTED) !=
|
|
0);
|
|
for (i = gChunkNumPages - 2; chunk->ndirty > 0; i--) {
|
|
MOZ_DIAGNOSTIC_ASSERT(i >= gChunkHeaderNumPages);
|
|
|
|
if (chunk->map[i].bits & CHUNK_MAP_DIRTY) {
|
|
#ifdef MALLOC_DECOMMIT
|
|
const size_t free_operation = CHUNK_MAP_DECOMMITTED;
|
|
#else
|
|
const size_t free_operation = CHUNK_MAP_MADVISED;
|
|
#endif
|
|
MOZ_ASSERT((chunk->map[i].bits & CHUNK_MAP_MADVISED_OR_DECOMMITTED) ==
|
|
0);
|
|
chunk->map[i].bits ^= free_operation | CHUNK_MAP_DIRTY;
|
|
// Find adjacent dirty run(s).
|
|
for (npages = 1; i > gChunkHeaderNumPages &&
|
|
(chunk->map[i - 1].bits & CHUNK_MAP_DIRTY);
|
|
npages++) {
|
|
i--;
|
|
MOZ_ASSERT((chunk->map[i].bits & CHUNK_MAP_MADVISED_OR_DECOMMITTED) ==
|
|
0);
|
|
chunk->map[i].bits ^= free_operation | CHUNK_MAP_DIRTY;
|
|
}
|
|
chunk->ndirty -= npages;
|
|
mNumDirty -= npages;
|
|
|
|
#ifdef MALLOC_DECOMMIT
|
|
pages_decommit((void*)(uintptr_t(chunk) + (i << gPageSize2Pow)),
|
|
(npages << gPageSize2Pow));
|
|
#endif
|
|
mStats.committed -= npages;
|
|
|
|
#ifndef MALLOC_DECOMMIT
|
|
# ifdef XP_SOLARIS
|
|
posix_madvise((void*)(uintptr_t(chunk) + (i << gPageSize2Pow)),
|
|
(npages << gPageSize2Pow), MADV_FREE);
|
|
# else
|
|
madvise((void*)(uintptr_t(chunk) + (i << gPageSize2Pow)),
|
|
(npages << gPageSize2Pow), MADV_FREE);
|
|
# endif
|
|
# ifdef MALLOC_DOUBLE_PURGE
|
|
madvised = true;
|
|
# endif
|
|
#endif
|
|
if (mNumDirty <= (dirty_max >> 1)) {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (chunk->ndirty == 0) {
|
|
mChunksDirty.Remove(chunk);
|
|
}
|
|
#ifdef MALLOC_DOUBLE_PURGE
|
|
if (madvised) {
|
|
// The chunk might already be in the list, but this
|
|
// makes sure it's at the front.
|
|
if (mChunksMAdvised.ElementProbablyInList(chunk)) {
|
|
mChunksMAdvised.remove(chunk);
|
|
}
|
|
mChunksMAdvised.pushFront(chunk);
|
|
}
|
|
#endif
|
|
}
|
|
}
|
|
|
|
void arena_t::DallocRun(arena_run_t* aRun, bool aDirty) {
|
|
arena_chunk_t* chunk;
|
|
size_t size, run_ind, run_pages;
|
|
|
|
chunk = GetChunkForPtr(aRun);
|
|
run_ind = (size_t)((uintptr_t(aRun) - uintptr_t(chunk)) >> gPageSize2Pow);
|
|
MOZ_DIAGNOSTIC_ASSERT(run_ind >= gChunkHeaderNumPages);
|
|
MOZ_RELEASE_ASSERT(run_ind < gChunkNumPages - 1);
|
|
if ((chunk->map[run_ind].bits & CHUNK_MAP_LARGE) != 0) {
|
|
size = chunk->map[run_ind].bits & ~gPageSizeMask;
|
|
} else {
|
|
size = aRun->mBin->mRunSize;
|
|
}
|
|
run_pages = (size >> gPageSize2Pow);
|
|
|
|
// Mark pages as unallocated in the chunk map.
|
|
if (aDirty) {
|
|
size_t i;
|
|
|
|
for (i = 0; i < run_pages; i++) {
|
|
MOZ_DIAGNOSTIC_ASSERT((chunk->map[run_ind + i].bits & CHUNK_MAP_DIRTY) ==
|
|
0);
|
|
chunk->map[run_ind + i].bits = CHUNK_MAP_DIRTY;
|
|
}
|
|
|
|
if (chunk->ndirty == 0) {
|
|
mChunksDirty.Insert(chunk);
|
|
}
|
|
chunk->ndirty += run_pages;
|
|
mNumDirty += run_pages;
|
|
} else {
|
|
size_t i;
|
|
|
|
for (i = 0; i < run_pages; i++) {
|
|
chunk->map[run_ind + i].bits &= ~(CHUNK_MAP_LARGE | CHUNK_MAP_ALLOCATED);
|
|
}
|
|
}
|
|
chunk->map[run_ind].bits = size | (chunk->map[run_ind].bits & gPageSizeMask);
|
|
chunk->map[run_ind + run_pages - 1].bits =
|
|
size | (chunk->map[run_ind + run_pages - 1].bits & gPageSizeMask);
|
|
|
|
// Try to coalesce forward.
|
|
if (run_ind + run_pages < gChunkNumPages - 1 &&
|
|
(chunk->map[run_ind + run_pages].bits & CHUNK_MAP_ALLOCATED) == 0) {
|
|
size_t nrun_size = chunk->map[run_ind + run_pages].bits & ~gPageSizeMask;
|
|
|
|
// Remove successor from tree of available runs; the coalesced run is
|
|
// inserted later.
|
|
mRunsAvail.Remove(&chunk->map[run_ind + run_pages]);
|
|
|
|
size += nrun_size;
|
|
run_pages = size >> gPageSize2Pow;
|
|
|
|
MOZ_DIAGNOSTIC_ASSERT((chunk->map[run_ind + run_pages - 1].bits &
|
|
~gPageSizeMask) == nrun_size);
|
|
chunk->map[run_ind].bits =
|
|
size | (chunk->map[run_ind].bits & gPageSizeMask);
|
|
chunk->map[run_ind + run_pages - 1].bits =
|
|
size | (chunk->map[run_ind + run_pages - 1].bits & gPageSizeMask);
|
|
}
|
|
|
|
// Try to coalesce backward.
|
|
if (run_ind > gChunkHeaderNumPages &&
|
|
(chunk->map[run_ind - 1].bits & CHUNK_MAP_ALLOCATED) == 0) {
|
|
size_t prun_size = chunk->map[run_ind - 1].bits & ~gPageSizeMask;
|
|
|
|
run_ind -= prun_size >> gPageSize2Pow;
|
|
|
|
// Remove predecessor from tree of available runs; the coalesced run is
|
|
// inserted later.
|
|
mRunsAvail.Remove(&chunk->map[run_ind]);
|
|
|
|
size += prun_size;
|
|
run_pages = size >> gPageSize2Pow;
|
|
|
|
MOZ_DIAGNOSTIC_ASSERT((chunk->map[run_ind].bits & ~gPageSizeMask) ==
|
|
prun_size);
|
|
chunk->map[run_ind].bits =
|
|
size | (chunk->map[run_ind].bits & gPageSizeMask);
|
|
chunk->map[run_ind + run_pages - 1].bits =
|
|
size | (chunk->map[run_ind + run_pages - 1].bits & gPageSizeMask);
|
|
}
|
|
|
|
// Insert into tree of available runs, now that coalescing is complete.
|
|
mRunsAvail.Insert(&chunk->map[run_ind]);
|
|
|
|
// Deallocate chunk if it is now completely unused.
|
|
if ((chunk->map[gChunkHeaderNumPages].bits &
|
|
(~gPageSizeMask | CHUNK_MAP_ALLOCATED)) == gMaxLargeClass) {
|
|
DeallocChunk(chunk);
|
|
}
|
|
|
|
// Enforce mMaxDirty.
|
|
if (mNumDirty > mMaxDirty) {
|
|
Purge(false);
|
|
}
|
|
}
|
|
|
|
void arena_t::TrimRunHead(arena_chunk_t* aChunk, arena_run_t* aRun,
|
|
size_t aOldSize, size_t aNewSize) {
|
|
size_t pageind = (uintptr_t(aRun) - uintptr_t(aChunk)) >> gPageSize2Pow;
|
|
size_t head_npages = (aOldSize - aNewSize) >> gPageSize2Pow;
|
|
|
|
MOZ_ASSERT(aOldSize > aNewSize);
|
|
|
|
// Update the chunk map so that arena_t::RunDalloc() can treat the
|
|
// leading run as separately allocated.
|
|
aChunk->map[pageind].bits =
|
|
(aOldSize - aNewSize) | CHUNK_MAP_LARGE | CHUNK_MAP_ALLOCATED;
|
|
aChunk->map[pageind + head_npages].bits =
|
|
aNewSize | CHUNK_MAP_LARGE | CHUNK_MAP_ALLOCATED;
|
|
|
|
DallocRun(aRun, false);
|
|
}
|
|
|
|
void arena_t::TrimRunTail(arena_chunk_t* aChunk, arena_run_t* aRun,
|
|
size_t aOldSize, size_t aNewSize, bool aDirty) {
|
|
size_t pageind = (uintptr_t(aRun) - uintptr_t(aChunk)) >> gPageSize2Pow;
|
|
size_t npages = aNewSize >> gPageSize2Pow;
|
|
|
|
MOZ_ASSERT(aOldSize > aNewSize);
|
|
|
|
// Update the chunk map so that arena_t::RunDalloc() can treat the
|
|
// trailing run as separately allocated.
|
|
aChunk->map[pageind].bits = aNewSize | CHUNK_MAP_LARGE | CHUNK_MAP_ALLOCATED;
|
|
aChunk->map[pageind + npages].bits =
|
|
(aOldSize - aNewSize) | CHUNK_MAP_LARGE | CHUNK_MAP_ALLOCATED;
|
|
|
|
DallocRun((arena_run_t*)(uintptr_t(aRun) + aNewSize), aDirty);
|
|
}
|
|
|
|
arena_run_t* arena_t::GetNonFullBinRun(arena_bin_t* aBin) {
|
|
arena_chunk_map_t* mapelm;
|
|
arena_run_t* run;
|
|
unsigned i, remainder;
|
|
|
|
// Look for a usable run.
|
|
mapelm = aBin->mNonFullRuns.First();
|
|
if (mapelm) {
|
|
// run is guaranteed to have available space.
|
|
aBin->mNonFullRuns.Remove(mapelm);
|
|
run = (arena_run_t*)(mapelm->bits & ~gPageSizeMask);
|
|
return run;
|
|
}
|
|
// No existing runs have any space available.
|
|
|
|
// Allocate a new run.
|
|
run = AllocRun(aBin->mRunSize, false, false);
|
|
if (!run) {
|
|
return nullptr;
|
|
}
|
|
// Don't initialize if a race in arena_t::RunAlloc() allowed an existing
|
|
// run to become usable.
|
|
if (run == aBin->mCurrentRun) {
|
|
return run;
|
|
}
|
|
|
|
// Initialize run internals.
|
|
run->mBin = aBin;
|
|
|
|
for (i = 0; i < aBin->mRunNumRegionsMask - 1; i++) {
|
|
run->mRegionsMask[i] = UINT_MAX;
|
|
}
|
|
remainder = aBin->mRunNumRegions & ((1U << (LOG2(sizeof(int)) + 3)) - 1);
|
|
if (remainder == 0) {
|
|
run->mRegionsMask[i] = UINT_MAX;
|
|
} else {
|
|
// The last element has spare bits that need to be unset.
|
|
run->mRegionsMask[i] =
|
|
(UINT_MAX >> ((1U << (LOG2(sizeof(int)) + 3)) - remainder));
|
|
}
|
|
|
|
run->mRegionsMinElement = 0;
|
|
|
|
run->mNumFree = aBin->mRunNumRegions;
|
|
#if defined(MOZ_DIAGNOSTIC_ASSERT_ENABLED)
|
|
run->mMagic = ARENA_RUN_MAGIC;
|
|
#endif
|
|
|
|
aBin->mNumRuns++;
|
|
return run;
|
|
}
|
|
|
|
void arena_bin_t::Init(SizeClass aSizeClass) {
|
|
size_t try_run_size;
|
|
unsigned try_nregs, try_mask_nelms, try_reg0_offset;
|
|
// Size of the run header, excluding mRegionsMask.
|
|
static const size_t kFixedHeaderSize = offsetof(arena_run_t, mRegionsMask);
|
|
|
|
MOZ_ASSERT(aSizeClass.Size() <= gMaxBinClass);
|
|
|
|
try_run_size = gPageSize;
|
|
|
|
mCurrentRun = nullptr;
|
|
mNonFullRuns.Init();
|
|
mSizeClass = aSizeClass.Size();
|
|
mNumRuns = 0;
|
|
|
|
// mRunSize expansion loop.
|
|
while (true) {
|
|
try_nregs = ((try_run_size - kFixedHeaderSize) / mSizeClass) +
|
|
1; // Counter-act try_nregs-- in loop.
|
|
|
|
// The do..while loop iteratively reduces the number of regions until
|
|
// the run header and the regions no longer overlap. A closed formula
|
|
// would be quite messy, since there is an interdependency between the
|
|
// header's mask length and the number of regions.
|
|
do {
|
|
try_nregs--;
|
|
try_mask_nelms =
|
|
(try_nregs >> (LOG2(sizeof(int)) + 3)) +
|
|
((try_nregs & ((1U << (LOG2(sizeof(int)) + 3)) - 1)) ? 1 : 0);
|
|
try_reg0_offset = try_run_size - (try_nregs * mSizeClass);
|
|
} while (kFixedHeaderSize + (sizeof(unsigned) * try_mask_nelms) >
|
|
try_reg0_offset);
|
|
|
|
// Try to keep the run overhead below kRunOverhead.
|
|
if (Fraction(try_reg0_offset, try_run_size) <= kRunOverhead) {
|
|
break;
|
|
}
|
|
|
|
// If the overhead is larger than the size class, it means the size class
|
|
// is small and doesn't align very well with the header. It's desirable to
|
|
// have smaller run sizes for them, so relax the overhead requirement.
|
|
if (try_reg0_offset > mSizeClass) {
|
|
if (Fraction(try_reg0_offset, try_run_size) <= kRunRelaxedOverhead) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
// The run header includes one bit per region of the given size. For sizes
|
|
// small enough, the number of regions is large enough that growing the run
|
|
// size barely moves the needle for the overhead because of all those bits.
|
|
// For example, for a size of 8 bytes, adding 4KiB to the run size adds
|
|
// close to 512 bits to the header, which is 64 bytes.
|
|
// With such overhead, there is no way to get to the wanted overhead above,
|
|
// so we give up if the required size for mRegionsMask more than doubles the
|
|
// size of the run header.
|
|
if (try_mask_nelms * sizeof(unsigned) >= kFixedHeaderSize) {
|
|
break;
|
|
}
|
|
|
|
// If next iteration is going to be larger than the largest possible large
|
|
// size class, then we didn't find a setup where the overhead is small
|
|
// enough, and we can't do better than the current settings, so just use
|
|
// that.
|
|
if (try_run_size + gPageSize > gMaxLargeClass) {
|
|
break;
|
|
}
|
|
|
|
// Try more aggressive settings.
|
|
try_run_size += gPageSize;
|
|
}
|
|
|
|
MOZ_ASSERT(kFixedHeaderSize + (sizeof(unsigned) * try_mask_nelms) <=
|
|
try_reg0_offset);
|
|
MOZ_ASSERT((try_mask_nelms << (LOG2(sizeof(int)) + 3)) >= try_nregs);
|
|
|
|
// Copy final settings.
|
|
mRunSize = try_run_size;
|
|
mRunNumRegions = try_nregs;
|
|
mRunNumRegionsMask = try_mask_nelms;
|
|
mRunFirstRegionOffset = try_reg0_offset;
|
|
}
|
|
|
|
void* arena_t::MallocSmall(size_t aSize, bool aZero) {
|
|
void* ret;
|
|
arena_bin_t* bin;
|
|
arena_run_t* run;
|
|
SizeClass sizeClass(aSize);
|
|
aSize = sizeClass.Size();
|
|
|
|
switch (sizeClass.Type()) {
|
|
case SizeClass::Tiny:
|
|
bin = &mBins[FloorLog2(aSize / kMinTinyClass)];
|
|
break;
|
|
case SizeClass::Quantum:
|
|
bin = &mBins[kNumTinyClasses + (aSize / kQuantum) - 1];
|
|
break;
|
|
case SizeClass::SubPage:
|
|
bin = &mBins[kNumTinyClasses + kNumQuantumClasses +
|
|
(FloorLog2(aSize / kMaxQuantumClass) - 1)];
|
|
break;
|
|
default:
|
|
MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE("Unexpected size class type");
|
|
}
|
|
MOZ_DIAGNOSTIC_ASSERT(aSize == bin->mSizeClass);
|
|
|
|
{
|
|
MutexAutoLock lock(mLock);
|
|
run = bin->mCurrentRun;
|
|
if (MOZ_UNLIKELY(!run || run->mNumFree == 0)) {
|
|
run = bin->mCurrentRun = GetNonFullBinRun(bin);
|
|
}
|
|
if (MOZ_UNLIKELY(!run)) {
|
|
return nullptr;
|
|
}
|
|
MOZ_DIAGNOSTIC_ASSERT(run->mMagic == ARENA_RUN_MAGIC);
|
|
MOZ_DIAGNOSTIC_ASSERT(run->mNumFree > 0);
|
|
ret = arena_run_reg_alloc(run, bin);
|
|
MOZ_DIAGNOSTIC_ASSERT(ret);
|
|
run->mNumFree--;
|
|
if (!ret) {
|
|
return nullptr;
|
|
}
|
|
|
|
mStats.allocated_small += aSize;
|
|
}
|
|
|
|
if (!aZero) {
|
|
ApplyZeroOrJunk(ret, aSize);
|
|
} else {
|
|
memset(ret, 0, aSize);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
void* arena_t::MallocLarge(size_t aSize, bool aZero) {
|
|
void* ret;
|
|
|
|
// Large allocation.
|
|
aSize = PAGE_CEILING(aSize);
|
|
|
|
{
|
|
MutexAutoLock lock(mLock);
|
|
ret = AllocRun(aSize, true, aZero);
|
|
if (!ret) {
|
|
return nullptr;
|
|
}
|
|
mStats.allocated_large += aSize;
|
|
}
|
|
|
|
if (!aZero) {
|
|
ApplyZeroOrJunk(ret, aSize);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
void* arena_t::Malloc(size_t aSize, bool aZero) {
|
|
MOZ_DIAGNOSTIC_ASSERT(mMagic == ARENA_MAGIC);
|
|
MOZ_ASSERT(aSize != 0);
|
|
|
|
if (aSize <= gMaxBinClass) {
|
|
return MallocSmall(aSize, aZero);
|
|
}
|
|
if (aSize <= gMaxLargeClass) {
|
|
return MallocLarge(aSize, aZero);
|
|
}
|
|
return MallocHuge(aSize, aZero);
|
|
}
|
|
|
|
// Only handles large allocations that require more than page alignment.
|
|
void* arena_t::PallocLarge(size_t aAlignment, size_t aSize, size_t aAllocSize) {
|
|
void* ret;
|
|
size_t offset;
|
|
arena_chunk_t* chunk;
|
|
|
|
MOZ_ASSERT((aSize & gPageSizeMask) == 0);
|
|
MOZ_ASSERT((aAlignment & gPageSizeMask) == 0);
|
|
|
|
{
|
|
MutexAutoLock lock(mLock);
|
|
ret = AllocRun(aAllocSize, true, false);
|
|
if (!ret) {
|
|
return nullptr;
|
|
}
|
|
|
|
chunk = GetChunkForPtr(ret);
|
|
|
|
offset = uintptr_t(ret) & (aAlignment - 1);
|
|
MOZ_ASSERT((offset & gPageSizeMask) == 0);
|
|
MOZ_ASSERT(offset < aAllocSize);
|
|
if (offset == 0) {
|
|
TrimRunTail(chunk, (arena_run_t*)ret, aAllocSize, aSize, false);
|
|
} else {
|
|
size_t leadsize, trailsize;
|
|
|
|
leadsize = aAlignment - offset;
|
|
if (leadsize > 0) {
|
|
TrimRunHead(chunk, (arena_run_t*)ret, aAllocSize,
|
|
aAllocSize - leadsize);
|
|
ret = (void*)(uintptr_t(ret) + leadsize);
|
|
}
|
|
|
|
trailsize = aAllocSize - leadsize - aSize;
|
|
if (trailsize != 0) {
|
|
// Trim trailing space.
|
|
MOZ_ASSERT(trailsize < aAllocSize);
|
|
TrimRunTail(chunk, (arena_run_t*)ret, aSize + trailsize, aSize, false);
|
|
}
|
|
}
|
|
|
|
mStats.allocated_large += aSize;
|
|
}
|
|
|
|
ApplyZeroOrJunk(ret, aSize);
|
|
return ret;
|
|
}
|
|
|
|
void* arena_t::Palloc(size_t aAlignment, size_t aSize) {
|
|
void* ret;
|
|
size_t ceil_size;
|
|
|
|
// Round size up to the nearest multiple of alignment.
|
|
//
|
|
// This done, we can take advantage of the fact that for each small
|
|
// size class, every object is aligned at the smallest power of two
|
|
// that is non-zero in the base two representation of the size. For
|
|
// example:
|
|
//
|
|
// Size | Base 2 | Minimum alignment
|
|
// -----+----------+------------------
|
|
// 96 | 1100000 | 32
|
|
// 144 | 10100000 | 32
|
|
// 192 | 11000000 | 64
|
|
//
|
|
// Depending on runtime settings, it is possible that arena_malloc()
|
|
// will further round up to a power of two, but that never causes
|
|
// correctness issues.
|
|
ceil_size = ALIGNMENT_CEILING(aSize, aAlignment);
|
|
|
|
// (ceil_size < aSize) protects against the combination of maximal
|
|
// alignment and size greater than maximal alignment.
|
|
if (ceil_size < aSize) {
|
|
// size_t overflow.
|
|
return nullptr;
|
|
}
|
|
|
|
if (ceil_size <= gPageSize ||
|
|
(aAlignment <= gPageSize && ceil_size <= gMaxLargeClass)) {
|
|
ret = Malloc(ceil_size, false);
|
|
} else {
|
|
size_t run_size;
|
|
|
|
// We can't achieve sub-page alignment, so round up alignment
|
|
// permanently; it makes later calculations simpler.
|
|
aAlignment = PAGE_CEILING(aAlignment);
|
|
ceil_size = PAGE_CEILING(aSize);
|
|
|
|
// (ceil_size < aSize) protects against very large sizes within
|
|
// pagesize of SIZE_T_MAX.
|
|
//
|
|
// (ceil_size + aAlignment < ceil_size) protects against the
|
|
// combination of maximal alignment and ceil_size large enough
|
|
// to cause overflow. This is similar to the first overflow
|
|
// check above, but it needs to be repeated due to the new
|
|
// ceil_size value, which may now be *equal* to maximal
|
|
// alignment, whereas before we only detected overflow if the
|
|
// original size was *greater* than maximal alignment.
|
|
if (ceil_size < aSize || ceil_size + aAlignment < ceil_size) {
|
|
// size_t overflow.
|
|
return nullptr;
|
|
}
|
|
|
|
// Calculate the size of the over-size run that arena_palloc()
|
|
// would need to allocate in order to guarantee the alignment.
|
|
if (ceil_size >= aAlignment) {
|
|
run_size = ceil_size + aAlignment - gPageSize;
|
|
} else {
|
|
// It is possible that (aAlignment << 1) will cause
|
|
// overflow, but it doesn't matter because we also
|
|
// subtract pagesize, which in the case of overflow
|
|
// leaves us with a very large run_size. That causes
|
|
// the first conditional below to fail, which means
|
|
// that the bogus run_size value never gets used for
|
|
// anything important.
|
|
run_size = (aAlignment << 1) - gPageSize;
|
|
}
|
|
|
|
if (run_size <= gMaxLargeClass) {
|
|
ret = PallocLarge(aAlignment, ceil_size, run_size);
|
|
} else if (aAlignment <= kChunkSize) {
|
|
ret = MallocHuge(ceil_size, false);
|
|
} else {
|
|
ret = PallocHuge(ceil_size, aAlignment, false);
|
|
}
|
|
}
|
|
|
|
MOZ_ASSERT((uintptr_t(ret) & (aAlignment - 1)) == 0);
|
|
return ret;
|
|
}
|
|
|
|
// Return the size of the allocation pointed to by ptr.
|
|
static size_t arena_salloc(const void* ptr) {
|
|
size_t ret;
|
|
arena_chunk_t* chunk;
|
|
size_t pageind, mapbits;
|
|
|
|
MOZ_ASSERT(ptr);
|
|
MOZ_ASSERT(GetChunkOffsetForPtr(ptr) != 0);
|
|
|
|
chunk = GetChunkForPtr(ptr);
|
|
pageind = (((uintptr_t)ptr - (uintptr_t)chunk) >> gPageSize2Pow);
|
|
mapbits = chunk->map[pageind].bits;
|
|
MOZ_DIAGNOSTIC_ASSERT((mapbits & CHUNK_MAP_ALLOCATED) != 0);
|
|
if ((mapbits & CHUNK_MAP_LARGE) == 0) {
|
|
arena_run_t* run = (arena_run_t*)(mapbits & ~gPageSizeMask);
|
|
MOZ_DIAGNOSTIC_ASSERT(run->mMagic == ARENA_RUN_MAGIC);
|
|
ret = run->mBin->mSizeClass;
|
|
} else {
|
|
ret = mapbits & ~gPageSizeMask;
|
|
MOZ_DIAGNOSTIC_ASSERT(ret != 0);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
class AllocInfo {
|
|
public:
|
|
template <bool Validate = false>
|
|
static inline AllocInfo Get(const void* aPtr) {
|
|
// If the allocator is not initialized, the pointer can't belong to it.
|
|
if (Validate && malloc_initialized == false) {
|
|
return AllocInfo();
|
|
}
|
|
|
|
auto chunk = GetChunkForPtr(aPtr);
|
|
if (Validate) {
|
|
if (!chunk || !gChunkRTree.Get(chunk)) {
|
|
return AllocInfo();
|
|
}
|
|
}
|
|
|
|
if (chunk != aPtr) {
|
|
MOZ_DIAGNOSTIC_ASSERT(chunk->arena->mMagic == ARENA_MAGIC);
|
|
return AllocInfo(arena_salloc(aPtr), chunk);
|
|
}
|
|
|
|
extent_node_t key;
|
|
|
|
// Huge allocation
|
|
key.mAddr = chunk;
|
|
MutexAutoLock lock(huge_mtx);
|
|
extent_node_t* node = huge.Search(&key);
|
|
if (Validate && !node) {
|
|
return AllocInfo();
|
|
}
|
|
return AllocInfo(node->mSize, node);
|
|
}
|
|
|
|
// Validate ptr before assuming that it points to an allocation. Currently,
|
|
// the following validation is performed:
|
|
//
|
|
// + Check that ptr is not nullptr.
|
|
//
|
|
// + Check that ptr lies within a mapped chunk.
|
|
static inline AllocInfo GetValidated(const void* aPtr) {
|
|
return Get<true>(aPtr);
|
|
}
|
|
|
|
AllocInfo() : mSize(0), mChunk(nullptr) {}
|
|
|
|
explicit AllocInfo(size_t aSize, arena_chunk_t* aChunk)
|
|
: mSize(aSize), mChunk(aChunk) {
|
|
MOZ_ASSERT(mSize <= gMaxLargeClass);
|
|
}
|
|
|
|
explicit AllocInfo(size_t aSize, extent_node_t* aNode)
|
|
: mSize(aSize), mNode(aNode) {
|
|
MOZ_ASSERT(mSize > gMaxLargeClass);
|
|
}
|
|
|
|
size_t Size() { return mSize; }
|
|
|
|
arena_t* Arena() {
|
|
return (mSize <= gMaxLargeClass) ? mChunk->arena : mNode->mArena;
|
|
}
|
|
|
|
private:
|
|
size_t mSize;
|
|
union {
|
|
// Pointer to the chunk associated with the allocation for small
|
|
// and large allocations.
|
|
arena_chunk_t* mChunk;
|
|
|
|
// Pointer to the extent node for huge allocations.
|
|
extent_node_t* mNode;
|
|
};
|
|
};
|
|
|
|
template <>
|
|
inline void MozJemalloc::jemalloc_ptr_info(const void* aPtr,
|
|
jemalloc_ptr_info_t* aInfo) {
|
|
arena_chunk_t* chunk = GetChunkForPtr(aPtr);
|
|
|
|
// Is the pointer null, or within one chunk's size of null?
|
|
// Alternatively, if the allocator is not initialized yet, the pointer
|
|
// can't be known.
|
|
if (!chunk || !malloc_initialized) {
|
|
*aInfo = {TagUnknown, nullptr, 0, 0};
|
|
return;
|
|
}
|
|
|
|
// Look for huge allocations before looking for |chunk| in gChunkRTree.
|
|
// This is necessary because |chunk| won't be in gChunkRTree if it's
|
|
// the second or subsequent chunk in a huge allocation.
|
|
extent_node_t* node;
|
|
extent_node_t key;
|
|
{
|
|
MutexAutoLock lock(huge_mtx);
|
|
key.mAddr = const_cast<void*>(aPtr);
|
|
node =
|
|
reinterpret_cast<RedBlackTree<extent_node_t, ExtentTreeBoundsTrait>*>(
|
|
&huge)
|
|
->Search(&key);
|
|
if (node) {
|
|
*aInfo = {TagLiveHuge, node->mAddr, node->mSize, node->mArena->mId};
|
|
return;
|
|
}
|
|
}
|
|
|
|
// It's not a huge allocation. Check if we have a known chunk.
|
|
if (!gChunkRTree.Get(chunk)) {
|
|
*aInfo = {TagUnknown, nullptr, 0, 0};
|
|
return;
|
|
}
|
|
|
|
MOZ_DIAGNOSTIC_ASSERT(chunk->arena->mMagic == ARENA_MAGIC);
|
|
|
|
// Get the page number within the chunk.
|
|
size_t pageind = (((uintptr_t)aPtr - (uintptr_t)chunk) >> gPageSize2Pow);
|
|
if (pageind < gChunkHeaderNumPages) {
|
|
// Within the chunk header.
|
|
*aInfo = {TagUnknown, nullptr, 0, 0};
|
|
return;
|
|
}
|
|
|
|
size_t mapbits = chunk->map[pageind].bits;
|
|
|
|
if (!(mapbits & CHUNK_MAP_ALLOCATED)) {
|
|
PtrInfoTag tag = TagFreedPageDirty;
|
|
if (mapbits & CHUNK_MAP_DIRTY) {
|
|
tag = TagFreedPageDirty;
|
|
} else if (mapbits & CHUNK_MAP_DECOMMITTED) {
|
|
tag = TagFreedPageDecommitted;
|
|
} else if (mapbits & CHUNK_MAP_MADVISED) {
|
|
tag = TagFreedPageMadvised;
|
|
} else if (mapbits & CHUNK_MAP_ZEROED) {
|
|
tag = TagFreedPageZeroed;
|
|
} else {
|
|
MOZ_CRASH();
|
|
}
|
|
|
|
void* pageaddr = (void*)(uintptr_t(aPtr) & ~gPageSizeMask);
|
|
*aInfo = {tag, pageaddr, gPageSize, chunk->arena->mId};
|
|
return;
|
|
}
|
|
|
|
if (mapbits & CHUNK_MAP_LARGE) {
|
|
// It's a large allocation. Only the first page of a large
|
|
// allocation contains its size, so if the address is not in
|
|
// the first page, scan back to find the allocation size.
|
|
size_t size;
|
|
while (true) {
|
|
size = mapbits & ~gPageSizeMask;
|
|
if (size != 0) {
|
|
break;
|
|
}
|
|
|
|
// The following two return paths shouldn't occur in
|
|
// practice unless there is heap corruption.
|
|
pageind--;
|
|
MOZ_DIAGNOSTIC_ASSERT(pageind >= gChunkHeaderNumPages);
|
|
if (pageind < gChunkHeaderNumPages) {
|
|
*aInfo = {TagUnknown, nullptr, 0, 0};
|
|
return;
|
|
}
|
|
|
|
mapbits = chunk->map[pageind].bits;
|
|
MOZ_DIAGNOSTIC_ASSERT(mapbits & CHUNK_MAP_LARGE);
|
|
if (!(mapbits & CHUNK_MAP_LARGE)) {
|
|
*aInfo = {TagUnknown, nullptr, 0, 0};
|
|
return;
|
|
}
|
|
}
|
|
|
|
void* addr = ((char*)chunk) + (pageind << gPageSize2Pow);
|
|
*aInfo = {TagLiveLarge, addr, size, chunk->arena->mId};
|
|
return;
|
|
}
|
|
|
|
// It must be a small allocation.
|
|
auto run = (arena_run_t*)(mapbits & ~gPageSizeMask);
|
|
MOZ_DIAGNOSTIC_ASSERT(run->mMagic == ARENA_RUN_MAGIC);
|
|
|
|
// The allocation size is stored in the run metadata.
|
|
size_t size = run->mBin->mSizeClass;
|
|
|
|
// Address of the first possible pointer in the run after its headers.
|
|
uintptr_t reg0_addr = (uintptr_t)run + run->mBin->mRunFirstRegionOffset;
|
|
if (aPtr < (void*)reg0_addr) {
|
|
// In the run header.
|
|
*aInfo = {TagUnknown, nullptr, 0, 0};
|
|
return;
|
|
}
|
|
|
|
// Position in the run.
|
|
unsigned regind = ((uintptr_t)aPtr - reg0_addr) / size;
|
|
|
|
// Pointer to the allocation's base address.
|
|
void* addr = (void*)(reg0_addr + regind * size);
|
|
|
|
// Check if the allocation has been freed.
|
|
unsigned elm = regind >> (LOG2(sizeof(int)) + 3);
|
|
unsigned bit = regind - (elm << (LOG2(sizeof(int)) + 3));
|
|
PtrInfoTag tag =
|
|
((run->mRegionsMask[elm] & (1U << bit))) ? TagFreedSmall : TagLiveSmall;
|
|
|
|
*aInfo = {tag, addr, size, chunk->arena->mId};
|
|
}
|
|
|
|
namespace Debug {
|
|
// Helper for debuggers. We don't want it to be inlined and optimized out.
|
|
MOZ_NEVER_INLINE jemalloc_ptr_info_t* jemalloc_ptr_info(const void* aPtr) {
|
|
static jemalloc_ptr_info_t info;
|
|
MozJemalloc::jemalloc_ptr_info(aPtr, &info);
|
|
return &info;
|
|
}
|
|
} // namespace Debug
|
|
|
|
void arena_t::DallocSmall(arena_chunk_t* aChunk, void* aPtr,
|
|
arena_chunk_map_t* aMapElm) {
|
|
arena_run_t* run;
|
|
arena_bin_t* bin;
|
|
size_t size;
|
|
|
|
run = (arena_run_t*)(aMapElm->bits & ~gPageSizeMask);
|
|
MOZ_DIAGNOSTIC_ASSERT(run->mMagic == ARENA_RUN_MAGIC);
|
|
bin = run->mBin;
|
|
size = bin->mSizeClass;
|
|
MOZ_DIAGNOSTIC_ASSERT(uintptr_t(aPtr) >=
|
|
uintptr_t(run) + bin->mRunFirstRegionOffset);
|
|
|
|
memset(aPtr, kAllocPoison, size);
|
|
|
|
arena_run_reg_dalloc(run, bin, aPtr, size);
|
|
run->mNumFree++;
|
|
|
|
if (run->mNumFree == bin->mRunNumRegions) {
|
|
// Deallocate run.
|
|
if (run == bin->mCurrentRun) {
|
|
bin->mCurrentRun = nullptr;
|
|
} else if (bin->mRunNumRegions != 1) {
|
|
size_t run_pageind =
|
|
(uintptr_t(run) - uintptr_t(aChunk)) >> gPageSize2Pow;
|
|
arena_chunk_map_t* run_mapelm = &aChunk->map[run_pageind];
|
|
|
|
// This block's conditional is necessary because if the
|
|
// run only contains one region, then it never gets
|
|
// inserted into the non-full runs tree.
|
|
MOZ_DIAGNOSTIC_ASSERT(bin->mNonFullRuns.Search(run_mapelm) == run_mapelm);
|
|
bin->mNonFullRuns.Remove(run_mapelm);
|
|
}
|
|
#if defined(MOZ_DIAGNOSTIC_ASSERT_ENABLED)
|
|
run->mMagic = 0;
|
|
#endif
|
|
DallocRun(run, true);
|
|
bin->mNumRuns--;
|
|
} else if (run->mNumFree == 1 && run != bin->mCurrentRun) {
|
|
// Make sure that bin->mCurrentRun always refers to the lowest
|
|
// non-full run, if one exists.
|
|
if (!bin->mCurrentRun) {
|
|
bin->mCurrentRun = run;
|
|
} else if (uintptr_t(run) < uintptr_t(bin->mCurrentRun)) {
|
|
// Switch mCurrentRun.
|
|
if (bin->mCurrentRun->mNumFree > 0) {
|
|
arena_chunk_t* runcur_chunk = GetChunkForPtr(bin->mCurrentRun);
|
|
size_t runcur_pageind =
|
|
(uintptr_t(bin->mCurrentRun) - uintptr_t(runcur_chunk)) >>
|
|
gPageSize2Pow;
|
|
arena_chunk_map_t* runcur_mapelm = &runcur_chunk->map[runcur_pageind];
|
|
|
|
// Insert runcur.
|
|
MOZ_DIAGNOSTIC_ASSERT(!bin->mNonFullRuns.Search(runcur_mapelm));
|
|
bin->mNonFullRuns.Insert(runcur_mapelm);
|
|
}
|
|
bin->mCurrentRun = run;
|
|
} else {
|
|
size_t run_pageind =
|
|
(uintptr_t(run) - uintptr_t(aChunk)) >> gPageSize2Pow;
|
|
arena_chunk_map_t* run_mapelm = &aChunk->map[run_pageind];
|
|
|
|
MOZ_DIAGNOSTIC_ASSERT(bin->mNonFullRuns.Search(run_mapelm) == nullptr);
|
|
bin->mNonFullRuns.Insert(run_mapelm);
|
|
}
|
|
}
|
|
mStats.allocated_small -= size;
|
|
}
|
|
|
|
void arena_t::DallocLarge(arena_chunk_t* aChunk, void* aPtr) {
|
|
MOZ_DIAGNOSTIC_ASSERT((uintptr_t(aPtr) & gPageSizeMask) == 0);
|
|
size_t pageind = (uintptr_t(aPtr) - uintptr_t(aChunk)) >> gPageSize2Pow;
|
|
size_t size = aChunk->map[pageind].bits & ~gPageSizeMask;
|
|
|
|
memset(aPtr, kAllocPoison, size);
|
|
mStats.allocated_large -= size;
|
|
|
|
DallocRun((arena_run_t*)aPtr, true);
|
|
}
|
|
|
|
static inline void arena_dalloc(void* aPtr, size_t aOffset, arena_t* aArena) {
|
|
MOZ_ASSERT(aPtr);
|
|
MOZ_ASSERT(aOffset != 0);
|
|
MOZ_ASSERT(GetChunkOffsetForPtr(aPtr) == aOffset);
|
|
|
|
auto chunk = (arena_chunk_t*)((uintptr_t)aPtr - aOffset);
|
|
auto arena = chunk->arena;
|
|
MOZ_ASSERT(arena);
|
|
MOZ_DIAGNOSTIC_ASSERT(arena->mMagic == ARENA_MAGIC);
|
|
MOZ_RELEASE_ASSERT(!aArena || arena == aArena);
|
|
|
|
MutexAutoLock lock(arena->mLock);
|
|
size_t pageind = aOffset >> gPageSize2Pow;
|
|
arena_chunk_map_t* mapelm = &chunk->map[pageind];
|
|
MOZ_RELEASE_ASSERT((mapelm->bits & CHUNK_MAP_DECOMMITTED) == 0,
|
|
"Freeing in decommitted page.");
|
|
MOZ_RELEASE_ASSERT((mapelm->bits & CHUNK_MAP_ALLOCATED) != 0, "Double-free?");
|
|
if ((mapelm->bits & CHUNK_MAP_LARGE) == 0) {
|
|
// Small allocation.
|
|
arena->DallocSmall(chunk, aPtr, mapelm);
|
|
} else {
|
|
// Large allocation.
|
|
arena->DallocLarge(chunk, aPtr);
|
|
}
|
|
}
|
|
|
|
static inline void idalloc(void* ptr, arena_t* aArena) {
|
|
size_t offset;
|
|
|
|
MOZ_ASSERT(ptr);
|
|
|
|
offset = GetChunkOffsetForPtr(ptr);
|
|
if (offset != 0) {
|
|
arena_dalloc(ptr, offset, aArena);
|
|
} else {
|
|
huge_dalloc(ptr, aArena);
|
|
}
|
|
}
|
|
|
|
void arena_t::RallocShrinkLarge(arena_chunk_t* aChunk, void* aPtr, size_t aSize,
|
|
size_t aOldSize) {
|
|
MOZ_ASSERT(aSize < aOldSize);
|
|
|
|
// Shrink the run, and make trailing pages available for other
|
|
// allocations.
|
|
MutexAutoLock lock(mLock);
|
|
TrimRunTail(aChunk, (arena_run_t*)aPtr, aOldSize, aSize, true);
|
|
mStats.allocated_large -= aOldSize - aSize;
|
|
}
|
|
|
|
// Returns whether reallocation was successful.
|
|
bool arena_t::RallocGrowLarge(arena_chunk_t* aChunk, void* aPtr, size_t aSize,
|
|
size_t aOldSize) {
|
|
size_t pageind = (uintptr_t(aPtr) - uintptr_t(aChunk)) >> gPageSize2Pow;
|
|
size_t npages = aOldSize >> gPageSize2Pow;
|
|
|
|
MutexAutoLock lock(mLock);
|
|
MOZ_DIAGNOSTIC_ASSERT(aOldSize ==
|
|
(aChunk->map[pageind].bits & ~gPageSizeMask));
|
|
|
|
// Try to extend the run.
|
|
MOZ_ASSERT(aSize > aOldSize);
|
|
if (pageind + npages < gChunkNumPages - 1 &&
|
|
(aChunk->map[pageind + npages].bits & CHUNK_MAP_ALLOCATED) == 0 &&
|
|
(aChunk->map[pageind + npages].bits & ~gPageSizeMask) >=
|
|
aSize - aOldSize) {
|
|
// The next run is available and sufficiently large. Split the
|
|
// following run, then merge the first part with the existing
|
|
// allocation.
|
|
if (!SplitRun((arena_run_t*)(uintptr_t(aChunk) +
|
|
((pageind + npages) << gPageSize2Pow)),
|
|
aSize - aOldSize, true, false)) {
|
|
return false;
|
|
}
|
|
|
|
aChunk->map[pageind].bits = aSize | CHUNK_MAP_LARGE | CHUNK_MAP_ALLOCATED;
|
|
aChunk->map[pageind + npages].bits = CHUNK_MAP_LARGE | CHUNK_MAP_ALLOCATED;
|
|
|
|
mStats.allocated_large += aSize - aOldSize;
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
void* arena_t::RallocSmallOrLarge(void* aPtr, size_t aSize, size_t aOldSize) {
|
|
void* ret;
|
|
size_t copysize;
|
|
SizeClass sizeClass(aSize);
|
|
|
|
// Try to avoid moving the allocation.
|
|
if (aOldSize <= gMaxLargeClass && sizeClass.Size() == aOldSize) {
|
|
if (aSize < aOldSize) {
|
|
memset((void*)(uintptr_t(aPtr) + aSize), kAllocPoison, aOldSize - aSize);
|
|
}
|
|
return aPtr;
|
|
}
|
|
if (sizeClass.Type() == SizeClass::Large && aOldSize > gMaxBinClass &&
|
|
aOldSize <= gMaxLargeClass) {
|
|
arena_chunk_t* chunk = GetChunkForPtr(aPtr);
|
|
if (sizeClass.Size() < aOldSize) {
|
|
// Fill before shrinking in order to avoid a race.
|
|
memset((void*)((uintptr_t)aPtr + aSize), kAllocPoison, aOldSize - aSize);
|
|
RallocShrinkLarge(chunk, aPtr, sizeClass.Size(), aOldSize);
|
|
return aPtr;
|
|
}
|
|
if (RallocGrowLarge(chunk, aPtr, sizeClass.Size(), aOldSize)) {
|
|
ApplyZeroOrJunk((void*)((uintptr_t)aPtr + aOldSize), aSize - aOldSize);
|
|
return aPtr;
|
|
}
|
|
}
|
|
|
|
// If we get here, then aSize and aOldSize are different enough that we
|
|
// need to move the object. In that case, fall back to allocating new
|
|
// space and copying.
|
|
ret = Malloc(aSize, false);
|
|
if (!ret) {
|
|
return nullptr;
|
|
}
|
|
|
|
// Junk/zero-filling were already done by arena_t::Malloc().
|
|
copysize = (aSize < aOldSize) ? aSize : aOldSize;
|
|
#ifdef VM_COPY_MIN
|
|
if (copysize >= VM_COPY_MIN) {
|
|
pages_copy(ret, aPtr, copysize);
|
|
} else
|
|
#endif
|
|
{
|
|
memcpy(ret, aPtr, copysize);
|
|
}
|
|
idalloc(aPtr, this);
|
|
return ret;
|
|
}
|
|
|
|
void* arena_t::Ralloc(void* aPtr, size_t aSize, size_t aOldSize) {
|
|
MOZ_DIAGNOSTIC_ASSERT(mMagic == ARENA_MAGIC);
|
|
MOZ_ASSERT(aPtr);
|
|
MOZ_ASSERT(aSize != 0);
|
|
|
|
return (aSize <= gMaxLargeClass) ? RallocSmallOrLarge(aPtr, aSize, aOldSize)
|
|
: RallocHuge(aPtr, aSize, aOldSize);
|
|
}
|
|
|
|
arena_t::arena_t(arena_params_t* aParams) {
|
|
unsigned i;
|
|
|
|
MOZ_RELEASE_ASSERT(mLock.Init());
|
|
|
|
memset(&mLink, 0, sizeof(mLink));
|
|
memset(&mStats, 0, sizeof(arena_stats_t));
|
|
|
|
// Initialize chunks.
|
|
mChunksDirty.Init();
|
|
#ifdef MALLOC_DOUBLE_PURGE
|
|
new (&mChunksMAdvised) DoublyLinkedList<arena_chunk_t>();
|
|
#endif
|
|
mSpare = nullptr;
|
|
|
|
mNumDirty = 0;
|
|
|
|
// The default maximum amount of dirty pages allowed on arenas is a fraction
|
|
// of opt_dirty_max.
|
|
mMaxDirty = (aParams && aParams->mMaxDirty) ? aParams->mMaxDirty
|
|
: (opt_dirty_max / 8);
|
|
|
|
mRunsAvail.Init();
|
|
|
|
// Initialize bins.
|
|
SizeClass sizeClass(1);
|
|
|
|
for (i = 0;; i++) {
|
|
arena_bin_t& bin = mBins[i];
|
|
bin.Init(sizeClass);
|
|
|
|
// SizeClass doesn't want sizes larger than gMaxSubPageClass for now.
|
|
if (sizeClass.Size() == gMaxSubPageClass) {
|
|
break;
|
|
}
|
|
sizeClass = sizeClass.Next();
|
|
}
|
|
MOZ_ASSERT(i ==
|
|
kNumTinyClasses + kNumQuantumClasses + gNumSubPageClasses - 1);
|
|
|
|
#if defined(MOZ_DIAGNOSTIC_ASSERT_ENABLED)
|
|
mMagic = ARENA_MAGIC;
|
|
#endif
|
|
}
|
|
|
|
arena_t* ArenaCollection::CreateArena(bool aIsPrivate,
|
|
arena_params_t* aParams) {
|
|
fallible_t fallible;
|
|
arena_t* ret = new (fallible) arena_t(aParams);
|
|
if (!ret) {
|
|
// Only reached if there is an OOM error.
|
|
|
|
// OOM here is quite inconvenient to propagate, since dealing with it
|
|
// would require a check for failure in the fast path. Instead, punt
|
|
// by using the first arena.
|
|
// In practice, this is an extremely unlikely failure.
|
|
_malloc_message(_getprogname(), ": (malloc) Error initializing arena\n");
|
|
|
|
return mDefaultArena;
|
|
}
|
|
|
|
MutexAutoLock lock(mLock);
|
|
|
|
// For public arenas, it's fine to just use incrementing arena id
|
|
if (!aIsPrivate) {
|
|
ret->mId = mLastPublicArenaId++;
|
|
mArenas.Insert(ret);
|
|
return ret;
|
|
}
|
|
|
|
// For private arenas, generate a cryptographically-secure random id for the
|
|
// new arena. If an attacker manages to get control of the process, this
|
|
// should make it more difficult for them to "guess" the ID of a memory
|
|
// arena, stopping them from getting data they may want
|
|
|
|
while (true) {
|
|
mozilla::Maybe<uint64_t> maybeRandomId = mozilla::RandomUint64();
|
|
MOZ_RELEASE_ASSERT(maybeRandomId.isSome());
|
|
|
|
// Keep looping until we ensure that the random number we just generated
|
|
// isn't already in use by another active arena
|
|
arena_t* existingArena =
|
|
GetByIdInternal(maybeRandomId.value(), true /*aIsPrivate*/);
|
|
|
|
if (!existingArena) {
|
|
ret->mId = static_cast<arena_id_t>(maybeRandomId.value());
|
|
mPrivateArenas.Insert(ret);
|
|
return ret;
|
|
}
|
|
}
|
|
}
|
|
|
|
// End arena.
|
|
// ***************************************************************************
|
|
// Begin general internal functions.
|
|
|
|
void* arena_t::MallocHuge(size_t aSize, bool aZero) {
|
|
return PallocHuge(aSize, kChunkSize, aZero);
|
|
}
|
|
|
|
void* arena_t::PallocHuge(size_t aSize, size_t aAlignment, bool aZero) {
|
|
void* ret;
|
|
size_t csize;
|
|
size_t psize;
|
|
extent_node_t* node;
|
|
bool zeroed;
|
|
|
|
// We're going to configure guard pages in the region between the
|
|
// page-aligned size and the chunk-aligned size, so if those are the same
|
|
// then we need to force that region into existence.
|
|
csize = CHUNK_CEILING(aSize + gPageSize);
|
|
if (csize < aSize) {
|
|
// size is large enough to cause size_t wrap-around.
|
|
return nullptr;
|
|
}
|
|
|
|
// Allocate an extent node with which to track the chunk.
|
|
node = base_node_alloc();
|
|
if (!node) {
|
|
return nullptr;
|
|
}
|
|
|
|
// Allocate one or more contiguous chunks for this request.
|
|
ret = chunk_alloc(csize, aAlignment, false, &zeroed);
|
|
if (!ret) {
|
|
base_node_dealloc(node);
|
|
return nullptr;
|
|
}
|
|
psize = PAGE_CEILING(aSize);
|
|
if (aZero) {
|
|
// We will decommit anything past psize so there is no need to zero
|
|
// further.
|
|
chunk_ensure_zero(ret, psize, zeroed);
|
|
}
|
|
|
|
// Insert node into huge.
|
|
node->mAddr = ret;
|
|
node->mSize = psize;
|
|
node->mArena = this;
|
|
|
|
{
|
|
MutexAutoLock lock(huge_mtx);
|
|
huge.Insert(node);
|
|
|
|
// Although we allocated space for csize bytes, we indicate that we've
|
|
// allocated only psize bytes.
|
|
//
|
|
// If DECOMMIT is defined, this is a reasonable thing to do, since
|
|
// we'll explicitly decommit the bytes in excess of psize.
|
|
//
|
|
// If DECOMMIT is not defined, then we're relying on the OS to be lazy
|
|
// about how it allocates physical pages to mappings. If we never
|
|
// touch the pages in excess of psize, the OS won't allocate a physical
|
|
// page, and we won't use more than psize bytes of physical memory.
|
|
//
|
|
// A correct program will only touch memory in excess of how much it
|
|
// requested if it first calls malloc_usable_size and finds out how
|
|
// much space it has to play with. But because we set node->mSize =
|
|
// psize above, malloc_usable_size will return psize, not csize, and
|
|
// the program will (hopefully) never touch bytes in excess of psize.
|
|
// Thus those bytes won't take up space in physical memory, and we can
|
|
// reasonably claim we never "allocated" them in the first place.
|
|
huge_allocated += psize;
|
|
huge_mapped += csize;
|
|
}
|
|
|
|
pages_decommit((void*)((uintptr_t)ret + psize), csize - psize);
|
|
|
|
if (!aZero) {
|
|
ApplyZeroOrJunk(ret, psize);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
void* arena_t::RallocHuge(void* aPtr, size_t aSize, size_t aOldSize) {
|
|
void* ret;
|
|
size_t copysize;
|
|
|
|
// Avoid moving the allocation if the size class would not change.
|
|
if (aOldSize > gMaxLargeClass &&
|
|
CHUNK_CEILING(aSize + gPageSize) == CHUNK_CEILING(aOldSize + gPageSize)) {
|
|
size_t psize = PAGE_CEILING(aSize);
|
|
if (aSize < aOldSize) {
|
|
memset((void*)((uintptr_t)aPtr + aSize), kAllocPoison, aOldSize - aSize);
|
|
}
|
|
if (psize < aOldSize) {
|
|
extent_node_t key;
|
|
|
|
pages_decommit((void*)((uintptr_t)aPtr + psize), aOldSize - psize);
|
|
|
|
// Update recorded size.
|
|
MutexAutoLock lock(huge_mtx);
|
|
key.mAddr = const_cast<void*>(aPtr);
|
|
extent_node_t* node = huge.Search(&key);
|
|
MOZ_ASSERT(node);
|
|
MOZ_ASSERT(node->mSize == aOldSize);
|
|
MOZ_RELEASE_ASSERT(node->mArena == this);
|
|
huge_allocated -= aOldSize - psize;
|
|
// No need to change huge_mapped, because we didn't (un)map anything.
|
|
node->mSize = psize;
|
|
} else if (psize > aOldSize) {
|
|
if (!pages_commit((void*)((uintptr_t)aPtr + aOldSize),
|
|
psize - aOldSize)) {
|
|
return nullptr;
|
|
}
|
|
|
|
// We need to update the recorded size if the size increased,
|
|
// so malloc_usable_size doesn't return a value smaller than
|
|
// what was requested via realloc().
|
|
extent_node_t key;
|
|
MutexAutoLock lock(huge_mtx);
|
|
key.mAddr = const_cast<void*>(aPtr);
|
|
extent_node_t* node = huge.Search(&key);
|
|
MOZ_ASSERT(node);
|
|
MOZ_ASSERT(node->mSize == aOldSize);
|
|
MOZ_RELEASE_ASSERT(node->mArena == this);
|
|
huge_allocated += psize - aOldSize;
|
|
// No need to change huge_mapped, because we didn't
|
|
// (un)map anything.
|
|
node->mSize = psize;
|
|
}
|
|
|
|
if (aSize > aOldSize) {
|
|
ApplyZeroOrJunk((void*)((uintptr_t)aPtr + aOldSize), aSize - aOldSize);
|
|
}
|
|
return aPtr;
|
|
}
|
|
|
|
// If we get here, then aSize and aOldSize are different enough that we
|
|
// need to use a different size class. In that case, fall back to
|
|
// allocating new space and copying.
|
|
ret = MallocHuge(aSize, false);
|
|
if (!ret) {
|
|
return nullptr;
|
|
}
|
|
|
|
copysize = (aSize < aOldSize) ? aSize : aOldSize;
|
|
#ifdef VM_COPY_MIN
|
|
if (copysize >= VM_COPY_MIN) {
|
|
pages_copy(ret, aPtr, copysize);
|
|
} else
|
|
#endif
|
|
{
|
|
memcpy(ret, aPtr, copysize);
|
|
}
|
|
idalloc(aPtr, this);
|
|
return ret;
|
|
}
|
|
|
|
static void huge_dalloc(void* aPtr, arena_t* aArena) {
|
|
extent_node_t* node;
|
|
size_t mapped = 0;
|
|
{
|
|
extent_node_t key;
|
|
MutexAutoLock lock(huge_mtx);
|
|
|
|
// Extract from tree of huge allocations.
|
|
key.mAddr = aPtr;
|
|
node = huge.Search(&key);
|
|
MOZ_RELEASE_ASSERT(node, "Double-free?");
|
|
MOZ_ASSERT(node->mAddr == aPtr);
|
|
MOZ_RELEASE_ASSERT(!aArena || node->mArena == aArena);
|
|
huge.Remove(node);
|
|
|
|
mapped = CHUNK_CEILING(node->mSize + gPageSize);
|
|
huge_allocated -= node->mSize;
|
|
huge_mapped -= mapped;
|
|
}
|
|
|
|
// Unmap chunk.
|
|
chunk_dealloc(node->mAddr, mapped, HUGE_CHUNK);
|
|
|
|
base_node_dealloc(node);
|
|
}
|
|
|
|
static size_t GetKernelPageSize() {
|
|
static size_t kernel_page_size = ([]() {
|
|
#ifdef XP_WIN
|
|
SYSTEM_INFO info;
|
|
GetSystemInfo(&info);
|
|
return info.dwPageSize;
|
|
#else
|
|
long result = sysconf(_SC_PAGESIZE);
|
|
MOZ_ASSERT(result != -1);
|
|
return result;
|
|
#endif
|
|
})();
|
|
return kernel_page_size;
|
|
}
|
|
|
|
// Returns whether the allocator was successfully initialized.
|
|
static bool malloc_init_hard() {
|
|
unsigned i;
|
|
const char* opts;
|
|
long result;
|
|
|
|
AutoLock<StaticMutex> lock(gInitLock);
|
|
|
|
if (malloc_initialized) {
|
|
// Another thread initialized the allocator before this one
|
|
// acquired gInitLock.
|
|
return true;
|
|
}
|
|
|
|
if (!thread_arena.init()) {
|
|
return true;
|
|
}
|
|
|
|
// Get page size and number of CPUs
|
|
result = GetKernelPageSize();
|
|
// We assume that the page size is a power of 2.
|
|
MOZ_ASSERT(((result - 1) & result) == 0);
|
|
#ifdef MALLOC_STATIC_PAGESIZE
|
|
if (gPageSize % (size_t)result) {
|
|
_malloc_message(
|
|
_getprogname(),
|
|
"Compile-time page size does not divide the runtime one.\n");
|
|
MOZ_CRASH();
|
|
}
|
|
#else
|
|
gPageSize = (size_t)result;
|
|
DefineGlobals();
|
|
#endif
|
|
|
|
// Get runtime configuration.
|
|
if ((opts = getenv("MALLOC_OPTIONS"))) {
|
|
for (i = 0; opts[i] != '\0'; i++) {
|
|
unsigned j, nreps;
|
|
bool nseen;
|
|
|
|
// Parse repetition count, if any.
|
|
for (nreps = 0, nseen = false;; i++, nseen = true) {
|
|
switch (opts[i]) {
|
|
case '0':
|
|
case '1':
|
|
case '2':
|
|
case '3':
|
|
case '4':
|
|
case '5':
|
|
case '6':
|
|
case '7':
|
|
case '8':
|
|
case '9':
|
|
nreps *= 10;
|
|
nreps += opts[i] - '0';
|
|
break;
|
|
default:
|
|
goto MALLOC_OUT;
|
|
}
|
|
}
|
|
MALLOC_OUT:
|
|
if (nseen == false) {
|
|
nreps = 1;
|
|
}
|
|
|
|
for (j = 0; j < nreps; j++) {
|
|
switch (opts[i]) {
|
|
case 'f':
|
|
opt_dirty_max >>= 1;
|
|
break;
|
|
case 'F':
|
|
if (opt_dirty_max == 0) {
|
|
opt_dirty_max = 1;
|
|
} else if ((opt_dirty_max << 1) != 0) {
|
|
opt_dirty_max <<= 1;
|
|
}
|
|
break;
|
|
#ifdef MOZ_DEBUG
|
|
case 'j':
|
|
opt_junk = false;
|
|
break;
|
|
case 'J':
|
|
opt_junk = true;
|
|
break;
|
|
#endif
|
|
#ifdef MOZ_DEBUG
|
|
case 'z':
|
|
opt_zero = false;
|
|
break;
|
|
case 'Z':
|
|
opt_zero = true;
|
|
break;
|
|
#endif
|
|
default: {
|
|
char cbuf[2];
|
|
|
|
cbuf[0] = opts[i];
|
|
cbuf[1] = '\0';
|
|
_malloc_message(_getprogname(),
|
|
": (malloc) Unsupported character "
|
|
"in malloc options: '",
|
|
cbuf, "'\n");
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
gRecycledSize = 0;
|
|
|
|
// Initialize chunks data.
|
|
chunks_mtx.Init();
|
|
gChunksBySize.Init();
|
|
gChunksByAddress.Init();
|
|
|
|
// Initialize huge allocation data.
|
|
huge_mtx.Init();
|
|
huge.Init();
|
|
huge_allocated = 0;
|
|
huge_mapped = 0;
|
|
|
|
// Initialize base allocation data structures.
|
|
base_mapped = 0;
|
|
base_committed = 0;
|
|
base_nodes = nullptr;
|
|
base_mtx.Init();
|
|
|
|
// Initialize arenas collection here.
|
|
if (!gArenas.Init()) {
|
|
return false;
|
|
}
|
|
|
|
// Assign the default arena to the initial thread.
|
|
thread_arena.set(gArenas.GetDefault());
|
|
|
|
if (!gChunkRTree.Init()) {
|
|
return false;
|
|
}
|
|
|
|
malloc_initialized = true;
|
|
|
|
// Dummy call so that the function is not removed by dead-code elimination
|
|
Debug::jemalloc_ptr_info(nullptr);
|
|
|
|
#if !defined(XP_WIN) && !defined(XP_DARWIN)
|
|
// Prevent potential deadlock on malloc locks after fork.
|
|
pthread_atfork(_malloc_prefork, _malloc_postfork_parent,
|
|
_malloc_postfork_child);
|
|
#endif
|
|
|
|
return true;
|
|
}
|
|
|
|
// End general internal functions.
|
|
// ***************************************************************************
|
|
// Begin malloc(3)-compatible functions.
|
|
|
|
// The BaseAllocator class is a helper class that implements the base allocator
|
|
// functions (malloc, calloc, realloc, free, memalign) for a given arena,
|
|
// or an appropriately chosen arena (per choose_arena()) when none is given.
|
|
struct BaseAllocator {
|
|
#define MALLOC_DECL(name, return_type, ...) \
|
|
inline return_type name(__VA_ARGS__);
|
|
|
|
#define MALLOC_FUNCS MALLOC_FUNCS_MALLOC_BASE
|
|
#include "malloc_decls.h"
|
|
|
|
explicit BaseAllocator(arena_t* aArena) : mArena(aArena) {}
|
|
|
|
private:
|
|
arena_t* mArena;
|
|
};
|
|
|
|
#define MALLOC_DECL(name, return_type, ...) \
|
|
template <> \
|
|
inline return_type MozJemalloc::name( \
|
|
ARGS_HELPER(TYPED_ARGS, ##__VA_ARGS__)) { \
|
|
BaseAllocator allocator(nullptr); \
|
|
return allocator.name(ARGS_HELPER(ARGS, ##__VA_ARGS__)); \
|
|
}
|
|
#define MALLOC_FUNCS MALLOC_FUNCS_MALLOC_BASE
|
|
#include "malloc_decls.h"
|
|
|
|
inline void* BaseAllocator::malloc(size_t aSize) {
|
|
void* ret;
|
|
arena_t* arena;
|
|
|
|
if (!malloc_init()) {
|
|
ret = nullptr;
|
|
goto RETURN;
|
|
}
|
|
|
|
if (aSize == 0) {
|
|
aSize = 1;
|
|
}
|
|
arena = mArena ? mArena : choose_arena(aSize);
|
|
ret = arena->Malloc(aSize, /* zero = */ false);
|
|
|
|
RETURN:
|
|
if (!ret) {
|
|
errno = ENOMEM;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
inline void* BaseAllocator::memalign(size_t aAlignment, size_t aSize) {
|
|
MOZ_ASSERT(((aAlignment - 1) & aAlignment) == 0);
|
|
|
|
if (!malloc_init()) {
|
|
return nullptr;
|
|
}
|
|
|
|
if (aSize == 0) {
|
|
aSize = 1;
|
|
}
|
|
|
|
aAlignment = aAlignment < sizeof(void*) ? sizeof(void*) : aAlignment;
|
|
arena_t* arena = mArena ? mArena : choose_arena(aSize);
|
|
return arena->Palloc(aAlignment, aSize);
|
|
}
|
|
|
|
inline void* BaseAllocator::calloc(size_t aNum, size_t aSize) {
|
|
void* ret;
|
|
|
|
if (malloc_init()) {
|
|
CheckedInt<size_t> checkedSize = CheckedInt<size_t>(aNum) * aSize;
|
|
if (checkedSize.isValid()) {
|
|
size_t allocSize = checkedSize.value();
|
|
if (allocSize == 0) {
|
|
allocSize = 1;
|
|
}
|
|
arena_t* arena = mArena ? mArena : choose_arena(allocSize);
|
|
ret = arena->Malloc(allocSize, /* zero = */ true);
|
|
} else {
|
|
ret = nullptr;
|
|
}
|
|
} else {
|
|
ret = nullptr;
|
|
}
|
|
|
|
if (!ret) {
|
|
errno = ENOMEM;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
inline void* BaseAllocator::realloc(void* aPtr, size_t aSize) {
|
|
void* ret;
|
|
|
|
if (aSize == 0) {
|
|
aSize = 1;
|
|
}
|
|
|
|
if (aPtr) {
|
|
MOZ_RELEASE_ASSERT(malloc_initialized);
|
|
|
|
auto info = AllocInfo::Get(aPtr);
|
|
auto arena = info.Arena();
|
|
MOZ_RELEASE_ASSERT(!mArena || arena == mArena);
|
|
ret = arena->Ralloc(aPtr, aSize, info.Size());
|
|
|
|
if (!ret) {
|
|
errno = ENOMEM;
|
|
}
|
|
} else {
|
|
if (!malloc_init()) {
|
|
ret = nullptr;
|
|
} else {
|
|
arena_t* arena = mArena ? mArena : choose_arena(aSize);
|
|
ret = arena->Malloc(aSize, /* zero = */ false);
|
|
}
|
|
|
|
if (!ret) {
|
|
errno = ENOMEM;
|
|
}
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
inline void BaseAllocator::free(void* aPtr) {
|
|
size_t offset;
|
|
|
|
// A version of idalloc that checks for nullptr pointer.
|
|
offset = GetChunkOffsetForPtr(aPtr);
|
|
if (offset != 0) {
|
|
MOZ_RELEASE_ASSERT(malloc_initialized);
|
|
arena_dalloc(aPtr, offset, mArena);
|
|
} else if (aPtr) {
|
|
MOZ_RELEASE_ASSERT(malloc_initialized);
|
|
huge_dalloc(aPtr, mArena);
|
|
}
|
|
}
|
|
|
|
template <void* (*memalign)(size_t, size_t)>
|
|
struct AlignedAllocator {
|
|
static inline int posix_memalign(void** aMemPtr, size_t aAlignment,
|
|
size_t aSize) {
|
|
void* result;
|
|
|
|
// alignment must be a power of two and a multiple of sizeof(void*)
|
|
if (((aAlignment - 1) & aAlignment) != 0 || aAlignment < sizeof(void*)) {
|
|
return EINVAL;
|
|
}
|
|
|
|
// The 0-->1 size promotion is done in the memalign() call below
|
|
result = memalign(aAlignment, aSize);
|
|
|
|
if (!result) {
|
|
return ENOMEM;
|
|
}
|
|
|
|
*aMemPtr = result;
|
|
return 0;
|
|
}
|
|
|
|
static inline void* aligned_alloc(size_t aAlignment, size_t aSize) {
|
|
if (aSize % aAlignment) {
|
|
return nullptr;
|
|
}
|
|
return memalign(aAlignment, aSize);
|
|
}
|
|
|
|
static inline void* valloc(size_t aSize) {
|
|
return memalign(GetKernelPageSize(), aSize);
|
|
}
|
|
};
|
|
|
|
template <>
|
|
inline int MozJemalloc::posix_memalign(void** aMemPtr, size_t aAlignment,
|
|
size_t aSize) {
|
|
return AlignedAllocator<memalign>::posix_memalign(aMemPtr, aAlignment, aSize);
|
|
}
|
|
|
|
template <>
|
|
inline void* MozJemalloc::aligned_alloc(size_t aAlignment, size_t aSize) {
|
|
return AlignedAllocator<memalign>::aligned_alloc(aAlignment, aSize);
|
|
}
|
|
|
|
template <>
|
|
inline void* MozJemalloc::valloc(size_t aSize) {
|
|
return AlignedAllocator<memalign>::valloc(aSize);
|
|
}
|
|
|
|
// End malloc(3)-compatible functions.
|
|
// ***************************************************************************
|
|
// Begin non-standard functions.
|
|
|
|
// This was added by Mozilla for use by SQLite.
|
|
template <>
|
|
inline size_t MozJemalloc::malloc_good_size(size_t aSize) {
|
|
if (aSize <= gMaxLargeClass) {
|
|
// Small or large
|
|
aSize = SizeClass(aSize).Size();
|
|
} else {
|
|
// Huge. We use PAGE_CEILING to get psize, instead of using
|
|
// CHUNK_CEILING to get csize. This ensures that this
|
|
// malloc_usable_size(malloc(n)) always matches
|
|
// malloc_good_size(n).
|
|
aSize = PAGE_CEILING(aSize);
|
|
}
|
|
return aSize;
|
|
}
|
|
|
|
template <>
|
|
inline size_t MozJemalloc::malloc_usable_size(usable_ptr_t aPtr) {
|
|
return AllocInfo::GetValidated(aPtr).Size();
|
|
}
|
|
|
|
template <>
|
|
inline void MozJemalloc::jemalloc_stats(jemalloc_stats_t* aStats) {
|
|
size_t non_arena_mapped, chunk_header_size;
|
|
|
|
if (!aStats) {
|
|
return;
|
|
}
|
|
if (!malloc_init()) {
|
|
memset(aStats, 0, sizeof(*aStats));
|
|
return;
|
|
}
|
|
|
|
// Gather runtime settings.
|
|
aStats->opt_junk = opt_junk;
|
|
aStats->opt_zero = opt_zero;
|
|
aStats->quantum = kQuantum;
|
|
aStats->small_max = kMaxQuantumClass;
|
|
aStats->large_max = gMaxLargeClass;
|
|
aStats->chunksize = kChunkSize;
|
|
aStats->page_size = gPageSize;
|
|
aStats->dirty_max = opt_dirty_max;
|
|
|
|
// Gather current memory usage statistics.
|
|
aStats->narenas = 0;
|
|
aStats->mapped = 0;
|
|
aStats->allocated = 0;
|
|
aStats->waste = 0;
|
|
aStats->page_cache = 0;
|
|
aStats->bookkeeping = 0;
|
|
aStats->bin_unused = 0;
|
|
|
|
non_arena_mapped = 0;
|
|
|
|
// Get huge mapped/allocated.
|
|
{
|
|
MutexAutoLock lock(huge_mtx);
|
|
non_arena_mapped += huge_mapped;
|
|
aStats->allocated += huge_allocated;
|
|
MOZ_ASSERT(huge_mapped >= huge_allocated);
|
|
}
|
|
|
|
// Get base mapped/allocated.
|
|
{
|
|
MutexAutoLock lock(base_mtx);
|
|
non_arena_mapped += base_mapped;
|
|
aStats->bookkeeping += base_committed;
|
|
MOZ_ASSERT(base_mapped >= base_committed);
|
|
}
|
|
|
|
gArenas.mLock.Lock();
|
|
// Iterate over arenas.
|
|
for (auto arena : gArenas.iter()) {
|
|
size_t arena_mapped, arena_allocated, arena_committed, arena_dirty, j,
|
|
arena_unused, arena_headers;
|
|
arena_run_t* run;
|
|
|
|
arena_headers = 0;
|
|
arena_unused = 0;
|
|
|
|
{
|
|
MutexAutoLock lock(arena->mLock);
|
|
|
|
arena_mapped = arena->mStats.mapped;
|
|
|
|
// "committed" counts dirty and allocated memory.
|
|
arena_committed = arena->mStats.committed << gPageSize2Pow;
|
|
|
|
arena_allocated =
|
|
arena->mStats.allocated_small + arena->mStats.allocated_large;
|
|
|
|
arena_dirty = arena->mNumDirty << gPageSize2Pow;
|
|
|
|
for (j = 0; j < kNumTinyClasses + kNumQuantumClasses + gNumSubPageClasses;
|
|
j++) {
|
|
arena_bin_t* bin = &arena->mBins[j];
|
|
size_t bin_unused = 0;
|
|
|
|
for (auto mapelm : bin->mNonFullRuns.iter()) {
|
|
run = (arena_run_t*)(mapelm->bits & ~gPageSizeMask);
|
|
bin_unused += run->mNumFree * bin->mSizeClass;
|
|
}
|
|
|
|
if (bin->mCurrentRun) {
|
|
bin_unused += bin->mCurrentRun->mNumFree * bin->mSizeClass;
|
|
}
|
|
|
|
arena_unused += bin_unused;
|
|
arena_headers += bin->mNumRuns * bin->mRunFirstRegionOffset;
|
|
}
|
|
}
|
|
|
|
MOZ_ASSERT(arena_mapped >= arena_committed);
|
|
MOZ_ASSERT(arena_committed >= arena_allocated + arena_dirty);
|
|
|
|
// "waste" is committed memory that is neither dirty nor
|
|
// allocated.
|
|
aStats->mapped += arena_mapped;
|
|
aStats->allocated += arena_allocated;
|
|
aStats->page_cache += arena_dirty;
|
|
aStats->waste += arena_committed - arena_allocated - arena_dirty -
|
|
arena_unused - arena_headers;
|
|
aStats->bin_unused += arena_unused;
|
|
aStats->bookkeeping += arena_headers;
|
|
aStats->narenas++;
|
|
}
|
|
gArenas.mLock.Unlock();
|
|
|
|
// Account for arena chunk headers in bookkeeping rather than waste.
|
|
chunk_header_size =
|
|
((aStats->mapped / aStats->chunksize) * gChunkHeaderNumPages)
|
|
<< gPageSize2Pow;
|
|
|
|
aStats->mapped += non_arena_mapped;
|
|
aStats->bookkeeping += chunk_header_size;
|
|
aStats->waste -= chunk_header_size;
|
|
|
|
MOZ_ASSERT(aStats->mapped >= aStats->allocated + aStats->waste +
|
|
aStats->page_cache + aStats->bookkeeping);
|
|
}
|
|
|
|
#ifdef MALLOC_DOUBLE_PURGE
|
|
|
|
// Explicitly remove all of this chunk's MADV_FREE'd pages from memory.
|
|
static void hard_purge_chunk(arena_chunk_t* aChunk) {
|
|
// See similar logic in arena_t::Purge().
|
|
for (size_t i = gChunkHeaderNumPages; i < gChunkNumPages; i++) {
|
|
// Find all adjacent pages with CHUNK_MAP_MADVISED set.
|
|
size_t npages;
|
|
for (npages = 0; aChunk->map[i + npages].bits & CHUNK_MAP_MADVISED &&
|
|
i + npages < gChunkNumPages;
|
|
npages++) {
|
|
// Turn off the chunk's MADV_FREED bit and turn on its
|
|
// DECOMMITTED bit.
|
|
MOZ_DIAGNOSTIC_ASSERT(
|
|
!(aChunk->map[i + npages].bits & CHUNK_MAP_DECOMMITTED));
|
|
aChunk->map[i + npages].bits ^= CHUNK_MAP_MADVISED_OR_DECOMMITTED;
|
|
}
|
|
|
|
// We could use mincore to find out which pages are actually
|
|
// present, but it's not clear that's better.
|
|
if (npages > 0) {
|
|
pages_decommit(((char*)aChunk) + (i << gPageSize2Pow),
|
|
npages << gPageSize2Pow);
|
|
Unused << pages_commit(((char*)aChunk) + (i << gPageSize2Pow),
|
|
npages << gPageSize2Pow);
|
|
}
|
|
i += npages;
|
|
}
|
|
}
|
|
|
|
// Explicitly remove all of this arena's MADV_FREE'd pages from memory.
|
|
void arena_t::HardPurge() {
|
|
MutexAutoLock lock(mLock);
|
|
|
|
while (!mChunksMAdvised.isEmpty()) {
|
|
arena_chunk_t* chunk = mChunksMAdvised.popFront();
|
|
hard_purge_chunk(chunk);
|
|
}
|
|
}
|
|
|
|
template <>
|
|
inline void MozJemalloc::jemalloc_purge_freed_pages() {
|
|
if (malloc_initialized) {
|
|
MutexAutoLock lock(gArenas.mLock);
|
|
for (auto arena : gArenas.iter()) {
|
|
arena->HardPurge();
|
|
}
|
|
}
|
|
}
|
|
|
|
#else // !defined MALLOC_DOUBLE_PURGE
|
|
|
|
template <>
|
|
inline void MozJemalloc::jemalloc_purge_freed_pages() {
|
|
// Do nothing.
|
|
}
|
|
|
|
#endif // defined MALLOC_DOUBLE_PURGE
|
|
|
|
template <>
|
|
inline void MozJemalloc::jemalloc_free_dirty_pages(void) {
|
|
if (malloc_initialized) {
|
|
MutexAutoLock lock(gArenas.mLock);
|
|
for (auto arena : gArenas.iter()) {
|
|
MutexAutoLock arena_lock(arena->mLock);
|
|
arena->Purge(true);
|
|
}
|
|
}
|
|
}
|
|
|
|
inline arena_t* ArenaCollection::GetByIdInternal(arena_id_t aArenaId,
|
|
bool aIsPrivate) {
|
|
// Use AlignedStorage2 to avoid running the arena_t constructor, while
|
|
// we only need it as a placeholder for mId.
|
|
mozilla::AlignedStorage2<arena_t> key;
|
|
key.addr()->mId = aArenaId;
|
|
return (aIsPrivate ? mPrivateArenas : mArenas).Search(key.addr());
|
|
}
|
|
|
|
inline arena_t* ArenaCollection::GetById(arena_id_t aArenaId, bool aIsPrivate) {
|
|
if (!malloc_initialized) {
|
|
return nullptr;
|
|
}
|
|
|
|
MutexAutoLock lock(mLock);
|
|
arena_t* result = GetByIdInternal(aArenaId, aIsPrivate);
|
|
MOZ_RELEASE_ASSERT(result);
|
|
return result;
|
|
}
|
|
|
|
template <>
|
|
inline arena_id_t MozJemalloc::moz_create_arena_with_params(
|
|
arena_params_t* aParams) {
|
|
if (malloc_init()) {
|
|
arena_t* arena = gArenas.CreateArena(/* IsPrivate = */ true, aParams);
|
|
return arena->mId;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
template <>
|
|
inline void MozJemalloc::moz_dispose_arena(arena_id_t aArenaId) {
|
|
// Until Bug 1364359 is fixed it is unsafe to call moz_dispose_arena.
|
|
// We want to catch any such occurances of that behavior.
|
|
MOZ_CRASH("Do not call moz_dispose_arena until Bug 1364359 is fixed.");
|
|
|
|
arena_t* arena = gArenas.GetById(aArenaId, /* IsPrivate = */ true);
|
|
MOZ_RELEASE_ASSERT(arena);
|
|
gArenas.DisposeArena(arena);
|
|
}
|
|
|
|
#define MALLOC_DECL(name, return_type, ...) \
|
|
template <> \
|
|
inline return_type MozJemalloc::moz_arena_##name( \
|
|
arena_id_t aArenaId, ARGS_HELPER(TYPED_ARGS, ##__VA_ARGS__)) { \
|
|
BaseAllocator allocator( \
|
|
gArenas.GetById(aArenaId, /* IsPrivate = */ true)); \
|
|
return allocator.name(ARGS_HELPER(ARGS, ##__VA_ARGS__)); \
|
|
}
|
|
#define MALLOC_FUNCS MALLOC_FUNCS_MALLOC_BASE
|
|
#include "malloc_decls.h"
|
|
|
|
// End non-standard functions.
|
|
// ***************************************************************************
|
|
#ifndef XP_WIN
|
|
// Begin library-private functions, used by threading libraries for protection
|
|
// of malloc during fork(). These functions are only called if the program is
|
|
// running in threaded mode, so there is no need to check whether the program
|
|
// is threaded here.
|
|
# ifndef XP_DARWIN
|
|
static
|
|
# endif
|
|
void
|
|
_malloc_prefork(void) {
|
|
// Acquire all mutexes in a safe order.
|
|
gArenas.mLock.Lock();
|
|
|
|
for (auto arena : gArenas.iter()) {
|
|
arena->mLock.Lock();
|
|
}
|
|
|
|
base_mtx.Lock();
|
|
|
|
huge_mtx.Lock();
|
|
}
|
|
|
|
# ifndef XP_DARWIN
|
|
static
|
|
# endif
|
|
void
|
|
_malloc_postfork_parent(void) {
|
|
// Release all mutexes, now that fork() has completed.
|
|
huge_mtx.Unlock();
|
|
|
|
base_mtx.Unlock();
|
|
|
|
for (auto arena : gArenas.iter()) {
|
|
arena->mLock.Unlock();
|
|
}
|
|
|
|
gArenas.mLock.Unlock();
|
|
}
|
|
|
|
# ifndef XP_DARWIN
|
|
static
|
|
# endif
|
|
void
|
|
_malloc_postfork_child(void) {
|
|
// Reinitialize all mutexes, now that fork() has completed.
|
|
huge_mtx.Init();
|
|
|
|
base_mtx.Init();
|
|
|
|
for (auto arena : gArenas.iter()) {
|
|
arena->mLock.Init();
|
|
}
|
|
|
|
gArenas.mLock.Init();
|
|
}
|
|
#endif // XP_WIN
|
|
|
|
// End library-private functions.
|
|
// ***************************************************************************
|
|
#ifdef MOZ_REPLACE_MALLOC
|
|
// Windows doesn't come with weak imports as they are possible with
|
|
// LD_PRELOAD or DYLD_INSERT_LIBRARIES on Linux/OSX. On this platform,
|
|
// the replacement functions are defined as variable pointers to the
|
|
// function resolved with GetProcAddress() instead of weak definitions
|
|
// of functions. On Android, the same needs to happen as well, because
|
|
// the Android linker doesn't handle weak linking with non LD_PRELOADed
|
|
// libraries, but LD_PRELOADing is not very convenient on Android, with
|
|
// the zygote.
|
|
# ifdef XP_DARWIN
|
|
# define MOZ_REPLACE_WEAK __attribute__((weak_import))
|
|
# elif defined(XP_WIN) || defined(ANDROID)
|
|
# define MOZ_DYNAMIC_REPLACE_INIT
|
|
# define replace_init replace_init_decl
|
|
# elif defined(__GNUC__)
|
|
# define MOZ_REPLACE_WEAK __attribute__((weak))
|
|
# endif
|
|
|
|
# include "replace_malloc.h"
|
|
|
|
# define MALLOC_DECL(name, return_type, ...) MozJemalloc::name,
|
|
|
|
static const malloc_table_t gReplaceMallocTableDefault = {
|
|
# include "malloc_decls.h"
|
|
};
|
|
static malloc_table_t gReplaceMallocTables[2] = {
|
|
{
|
|
# include "malloc_decls.h"
|
|
},
|
|
{
|
|
# include "malloc_decls.h"
|
|
},
|
|
};
|
|
unsigned gReplaceMallocIndex = 0;
|
|
|
|
// Avoid races when swapping malloc impls dynamically
|
|
static Atomic<malloc_table_t const*, mozilla::MemoryOrdering::Relaxed,
|
|
recordreplay::Behavior::DontPreserve>
|
|
gReplaceMallocTable;
|
|
|
|
# ifdef MOZ_DYNAMIC_REPLACE_INIT
|
|
# undef replace_init
|
|
typedef decltype(replace_init_decl) replace_init_impl_t;
|
|
static replace_init_impl_t* replace_init = nullptr;
|
|
# endif
|
|
|
|
# ifdef XP_WIN
|
|
typedef HMODULE replace_malloc_handle_t;
|
|
|
|
static replace_malloc_handle_t replace_malloc_handle() {
|
|
wchar_t replace_malloc_lib[1024];
|
|
if (GetEnvironmentVariableW(L"MOZ_REPLACE_MALLOC_LIB", replace_malloc_lib,
|
|
ArrayLength(replace_malloc_lib)) > 0) {
|
|
return LoadLibraryW(replace_malloc_lib);
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
# define REPLACE_MALLOC_GET_INIT_FUNC(handle) \
|
|
(replace_init_impl_t*)GetProcAddress(handle, "replace_init")
|
|
|
|
# elif defined(ANDROID)
|
|
# include <dlfcn.h>
|
|
|
|
typedef void* replace_malloc_handle_t;
|
|
|
|
static replace_malloc_handle_t replace_malloc_handle() {
|
|
const char* replace_malloc_lib = getenv("MOZ_REPLACE_MALLOC_LIB");
|
|
if (replace_malloc_lib && *replace_malloc_lib) {
|
|
return dlopen(replace_malloc_lib, RTLD_LAZY);
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
# define REPLACE_MALLOC_GET_INIT_FUNC(handle) \
|
|
(replace_init_impl_t*)dlsym(handle, "replace_init")
|
|
|
|
# endif
|
|
|
|
static void replace_malloc_init_funcs(malloc_table_t*);
|
|
|
|
# ifdef MOZ_REPLACE_MALLOC_STATIC
|
|
extern "C" void logalloc_init(malloc_table_t*, ReplaceMallocBridge**);
|
|
|
|
extern "C" void dmd_init(malloc_table_t*, ReplaceMallocBridge**);
|
|
# endif
|
|
|
|
bool Equals(const malloc_table_t& aTable1, const malloc_table_t& aTable2) {
|
|
return memcmp(&aTable1, &aTable2, sizeof(malloc_table_t)) == 0;
|
|
}
|
|
|
|
// Below is the malloc implementation overriding jemalloc and calling the
|
|
// replacement functions if they exist.
|
|
static ReplaceMallocBridge* gReplaceMallocBridge = nullptr;
|
|
static void init() {
|
|
malloc_table_t tempTable = gReplaceMallocTableDefault;
|
|
|
|
# ifdef MOZ_DYNAMIC_REPLACE_INIT
|
|
replace_malloc_handle_t handle = replace_malloc_handle();
|
|
if (handle) {
|
|
replace_init = REPLACE_MALLOC_GET_INIT_FUNC(handle);
|
|
}
|
|
# endif
|
|
|
|
// Set this *before* calling replace_init, otherwise if replace_init calls
|
|
// malloc() we'll get an infinite loop.
|
|
gReplaceMallocTable = &gReplaceMallocTableDefault;
|
|
|
|
// Pass in the a new (default allocator table so replace functions can
|
|
// copy and use it for their allocations. The replace_init() function
|
|
// should modify the table if it wants to be active, otherwise leave it
|
|
// unmodified.
|
|
if (replace_init) {
|
|
replace_init(&tempTable, &gReplaceMallocBridge);
|
|
}
|
|
# ifdef MOZ_REPLACE_MALLOC_STATIC
|
|
if (Equals(tempTable, gReplaceMallocTableDefault)) {
|
|
logalloc_init(&tempTable, &gReplaceMallocBridge);
|
|
}
|
|
# ifdef MOZ_DMD
|
|
if (Equals(tempTable, gReplaceMallocTableDefault)) {
|
|
dmd_init(&tempTable, &gReplaceMallocBridge);
|
|
}
|
|
# endif
|
|
# endif
|
|
if (!Equals(tempTable, gReplaceMallocTableDefault)) {
|
|
replace_malloc_init_funcs(&tempTable);
|
|
gReplaceMallocIndex = (gReplaceMallocIndex + 1) % 2;
|
|
gReplaceMallocTables[gReplaceMallocIndex] = tempTable;
|
|
// Atomic change
|
|
gReplaceMallocTable = &gReplaceMallocTables[gReplaceMallocIndex];
|
|
}
|
|
}
|
|
|
|
// Note: since other allocations have happened before this, it must deal
|
|
// with allocations being freed that weren't allocated through it, and when
|
|
// it's removed the normal allocator must deal with allocations made by the
|
|
// replacement that are freed by the normal allocator.
|
|
//
|
|
// This means that simple replacements that don't modify much about the
|
|
// allocations or just record information about it are fine.
|
|
MOZ_JEMALLOC_API void jemalloc_replace_dynamic(
|
|
jemalloc_init_func replace_init_func) {
|
|
malloc_table_t tempTable = gReplaceMallocTableDefault;
|
|
if (replace_init_func) {
|
|
(*replace_init_func)(&tempTable, &gReplaceMallocBridge);
|
|
if (!Equals(tempTable, gReplaceMallocTableDefault)) {
|
|
replace_malloc_init_funcs(&tempTable);
|
|
// flip-flop between two tables
|
|
gReplaceMallocIndex = (gReplaceMallocIndex + 1) % 2;
|
|
gReplaceMallocTables[gReplaceMallocIndex] = tempTable;
|
|
gReplaceMallocTable = &gReplaceMallocTables[gReplaceMallocIndex];
|
|
// We assume that dynamic replaces don't occur close enough for a
|
|
// thread to still have old copies of the table pointer when the 2nd
|
|
// replace occurs.
|
|
return;
|
|
}
|
|
}
|
|
// When a replacer is removed, switch back to the original default. A
|
|
// new replacement will not immediately re-use the same table array index
|
|
// as the last malloc replacer.
|
|
gReplaceMallocTable = &gReplaceMallocTableDefault;
|
|
}
|
|
|
|
# define MALLOC_DECL(name, return_type, ...) \
|
|
template <> \
|
|
inline return_type ReplaceMalloc::name( \
|
|
ARGS_HELPER(TYPED_ARGS, ##__VA_ARGS__)) { \
|
|
if (MOZ_UNLIKELY(!gReplaceMallocTable)) { \
|
|
init(); \
|
|
} \
|
|
return (*gReplaceMallocTable).name(ARGS_HELPER(ARGS, ##__VA_ARGS__)); \
|
|
}
|
|
# include "malloc_decls.h"
|
|
|
|
MOZ_JEMALLOC_API struct ReplaceMallocBridge* get_bridge(void) {
|
|
if (MOZ_UNLIKELY(!gReplaceMallocTable)) {
|
|
init();
|
|
}
|
|
return gReplaceMallocBridge;
|
|
}
|
|
|
|
// posix_memalign, aligned_alloc, memalign and valloc all implement some kind
|
|
// of aligned memory allocation. For convenience, a replace-malloc library can
|
|
// skip defining replace_posix_memalign, replace_aligned_alloc and
|
|
// replace_valloc, and default implementations will be automatically derived
|
|
// from replace_memalign.
|
|
static void replace_malloc_init_funcs(malloc_table_t* table) {
|
|
if (table->posix_memalign == MozJemalloc::posix_memalign &&
|
|
table->memalign != MozJemalloc::memalign) {
|
|
table->posix_memalign =
|
|
AlignedAllocator<ReplaceMalloc::memalign>::posix_memalign;
|
|
}
|
|
if (table->aligned_alloc == MozJemalloc::aligned_alloc &&
|
|
table->memalign != MozJemalloc::memalign) {
|
|
table->aligned_alloc =
|
|
AlignedAllocator<ReplaceMalloc::memalign>::aligned_alloc;
|
|
}
|
|
if (table->valloc == MozJemalloc::valloc &&
|
|
table->memalign != MozJemalloc::memalign) {
|
|
table->valloc = AlignedAllocator<ReplaceMalloc::memalign>::valloc;
|
|
}
|
|
if (table->moz_create_arena_with_params ==
|
|
MozJemalloc::moz_create_arena_with_params &&
|
|
table->malloc != MozJemalloc::malloc) {
|
|
# define MALLOC_DECL(name, ...) \
|
|
table->name = DummyArenaAllocator<ReplaceMalloc>::name;
|
|
# define MALLOC_FUNCS MALLOC_FUNCS_ARENA_BASE
|
|
# include "malloc_decls.h"
|
|
}
|
|
if (table->moz_arena_malloc == MozJemalloc::moz_arena_malloc &&
|
|
table->malloc != MozJemalloc::malloc) {
|
|
# define MALLOC_DECL(name, ...) \
|
|
table->name = DummyArenaAllocator<ReplaceMalloc>::name;
|
|
# define MALLOC_FUNCS MALLOC_FUNCS_ARENA_ALLOC
|
|
# include "malloc_decls.h"
|
|
}
|
|
}
|
|
|
|
#endif // MOZ_REPLACE_MALLOC
|
|
// ***************************************************************************
|
|
// Definition of all the _impl functions
|
|
|
|
#define GENERIC_MALLOC_DECL2(name, name_impl, return_type, ...) \
|
|
return_type name_impl(ARGS_HELPER(TYPED_ARGS, ##__VA_ARGS__)) { \
|
|
return DefaultMalloc::name(ARGS_HELPER(ARGS, ##__VA_ARGS__)); \
|
|
}
|
|
|
|
#define GENERIC_MALLOC_DECL(name, return_type, ...) \
|
|
GENERIC_MALLOC_DECL2(name, name##_impl, return_type, ##__VA_ARGS__)
|
|
|
|
#define MALLOC_DECL(...) \
|
|
MOZ_MEMORY_API MACRO_CALL(GENERIC_MALLOC_DECL, (__VA_ARGS__))
|
|
#define MALLOC_FUNCS MALLOC_FUNCS_MALLOC
|
|
#include "malloc_decls.h"
|
|
|
|
#undef GENERIC_MALLOC_DECL
|
|
#define GENERIC_MALLOC_DECL(name, return_type, ...) \
|
|
GENERIC_MALLOC_DECL2(name, name, return_type, ##__VA_ARGS__)
|
|
|
|
#define MALLOC_DECL(...) \
|
|
MOZ_JEMALLOC_API MACRO_CALL(GENERIC_MALLOC_DECL, (__VA_ARGS__))
|
|
#define MALLOC_FUNCS (MALLOC_FUNCS_JEMALLOC | MALLOC_FUNCS_ARENA)
|
|
#include "malloc_decls.h"
|
|
// ***************************************************************************
|
|
|
|
#ifdef HAVE_DLOPEN
|
|
# include <dlfcn.h>
|
|
#endif
|
|
|
|
#if defined(__GLIBC__) && !defined(__UCLIBC__)
|
|
// glibc provides the RTLD_DEEPBIND flag for dlopen which can make it possible
|
|
// to inconsistently reference libc's malloc(3)-compatible functions
|
|
// (bug 493541).
|
|
//
|
|
// These definitions interpose hooks in glibc. The functions are actually
|
|
// passed an extra argument for the caller return address, which will be
|
|
// ignored.
|
|
|
|
extern "C" {
|
|
MOZ_EXPORT void (*__free_hook)(void*) = free_impl;
|
|
MOZ_EXPORT void* (*__malloc_hook)(size_t) = malloc_impl;
|
|
MOZ_EXPORT void* (*__realloc_hook)(void*, size_t) = realloc_impl;
|
|
MOZ_EXPORT void* (*__memalign_hook)(size_t, size_t) = memalign_impl;
|
|
}
|
|
|
|
#elif defined(RTLD_DEEPBIND)
|
|
// XXX On systems that support RTLD_GROUP or DF_1_GROUP, do their
|
|
// implementations permit similar inconsistencies? Should STV_SINGLETON
|
|
// visibility be used for interposition where available?
|
|
# error \
|
|
"Interposing malloc is unsafe on this system without libc malloc hooks."
|
|
#endif
|
|
|
|
#ifdef XP_WIN
|
|
void* _recalloc(void* aPtr, size_t aCount, size_t aSize) {
|
|
size_t oldsize = aPtr ? AllocInfo::Get(aPtr).Size() : 0;
|
|
CheckedInt<size_t> checkedSize = CheckedInt<size_t>(aCount) * aSize;
|
|
|
|
if (!checkedSize.isValid()) {
|
|
return nullptr;
|
|
}
|
|
|
|
size_t newsize = checkedSize.value();
|
|
|
|
// In order for all trailing bytes to be zeroed, the caller needs to
|
|
// use calloc(), followed by recalloc(). However, the current calloc()
|
|
// implementation only zeros the bytes requested, so if recalloc() is
|
|
// to work 100% correctly, calloc() will need to change to zero
|
|
// trailing bytes.
|
|
aPtr = DefaultMalloc::realloc(aPtr, newsize);
|
|
if (aPtr && oldsize < newsize) {
|
|
memset((void*)((uintptr_t)aPtr + oldsize), 0, newsize - oldsize);
|
|
}
|
|
|
|
return aPtr;
|
|
}
|
|
|
|
// This impl of _expand doesn't ever actually expand or shrink blocks: it
|
|
// simply replies that you may continue using a shrunk block.
|
|
void* _expand(void* aPtr, size_t newsize) {
|
|
if (AllocInfo::Get(aPtr).Size() >= newsize) {
|
|
return aPtr;
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
size_t _msize(void* aPtr) { return DefaultMalloc::malloc_usable_size(aPtr); }
|
|
#endif
|