| Index: Source/WTF/wtf/FastMalloc.cpp
|
| diff --git a/Source/WTF/wtf/FastMalloc.cpp b/Source/WTF/wtf/FastMalloc.cpp
|
| deleted file mode 100644
|
| index e58be0f6bfd813e9f921ad27c8d934bb2708d97c..0000000000000000000000000000000000000000
|
| --- a/Source/WTF/wtf/FastMalloc.cpp
|
| +++ /dev/null
|
| @@ -1,4934 +0,0 @@
|
| -// Copyright (c) 2005, 2007, Google Inc.
|
| -// All rights reserved.
|
| -// Copyright (C) 2005, 2006, 2007, 2008, 2009, 2011 Apple Inc. All rights reserved.
|
| -//
|
| -// Redistribution and use in source and binary forms, with or without
|
| -// modification, are permitted provided that the following conditions are
|
| -// met:
|
| -//
|
| -// * Redistributions of source code must retain the above copyright
|
| -// notice, this list of conditions and the following disclaimer.
|
| -// * Redistributions in binary form must reproduce the above
|
| -// copyright notice, this list of conditions and the following disclaimer
|
| -// in the documentation and/or other materials provided with the
|
| -// distribution.
|
| -// * Neither the name of Google Inc. nor the names of its
|
| -// contributors may be used to endorse or promote products derived from
|
| -// this software without specific prior written permission.
|
| -//
|
| -// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
| -// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
| -// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
| -// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
| -// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
| -// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
| -// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
| -// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
| -// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
| -// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
| -// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
| -
|
| -// ---
|
| -// Author: Sanjay Ghemawat <opensource@google.com>
|
| -//
|
| -// A malloc that uses a per-thread cache to satisfy small malloc requests.
|
| -// (The time for malloc/free of a small object drops from 300 ns to 50 ns.)
|
| -//
|
| -// See doc/tcmalloc.html for a high-level
|
| -// description of how this malloc works.
|
| -//
|
| -// SYNCHRONIZATION
|
| -// 1. The thread-specific lists are accessed without acquiring any locks.
|
| -// This is safe because each such list is only accessed by one thread.
|
| -// 2. We have a lock per central free-list, and hold it while manipulating
|
| -// the central free list for a particular size.
|
| -// 3. The central page allocator is protected by "pageheap_lock".
|
| -// 4. The pagemap (which maps from page-number to descriptor),
|
| -// can be read without holding any locks, and written while holding
|
| -// the "pageheap_lock".
|
| -// 5. To improve performance, a subset of the information one can get
|
| -// from the pagemap is cached in a data structure, pagemap_cache_,
|
| -// that atomically reads and writes its entries. This cache can be
|
| -// read and written without locking.
|
| -//
|
| -// This multi-threaded access to the pagemap is safe for fairly
|
| -// subtle reasons. We basically assume that when an object X is
|
| -// allocated by thread A and deallocated by thread B, there must
|
| -// have been appropriate synchronization in the handoff of object
|
| -// X from thread A to thread B. The same logic applies to pagemap_cache_.
|
| -//
|
| -// THE PAGEID-TO-SIZECLASS CACHE
|
| -// Hot PageID-to-sizeclass mappings are held by pagemap_cache_. If this cache
|
| -// returns 0 for a particular PageID then that means "no information," not that
|
| -// the sizeclass is 0. The cache may have stale information for pages that do
|
| -// not hold the beginning of any free()'able object. Staleness is eliminated
|
| -// in Populate() for pages with sizeclass > 0 objects, and in do_malloc() and
|
| -// do_memalign() for all other relevant pages.
|
| -//
|
| -// TODO: Bias reclamation to larger addresses
|
| -// TODO: implement mallinfo/mallopt
|
| -// TODO: Better testing
|
| -//
|
| -// 9/28/2003 (new page-level allocator replaces ptmalloc2):
|
| -// * malloc/free of small objects goes from ~300 ns to ~50 ns.
|
| -// * allocation of a reasonably complicated struct
|
| -// goes from about 1100 ns to about 300 ns.
|
| -
|
| -#include "config.h"
|
| -#include "FastMalloc.h"
|
| -
|
| -#include "Assertions.h"
|
| -
|
| -#include <limits>
|
| -#if OS(WINDOWS)
|
| -#include <windows.h>
|
| -#else
|
| -#include <pthread.h>
|
| -#endif
|
| -#include <string.h>
|
| -#include <wtf/StdLibExtras.h>
|
| -#include <wtf/UnusedParam.h>
|
| -
|
| -#ifndef NO_TCMALLOC_SAMPLES
|
| -#ifdef WTF_CHANGES
|
| -#define NO_TCMALLOC_SAMPLES
|
| -#endif
|
| -#endif
|
| -
|
| -#if !USE(SYSTEM_MALLOC) && defined(NDEBUG)
|
| -#define FORCE_SYSTEM_MALLOC 0
|
| -#else
|
| -#define FORCE_SYSTEM_MALLOC 1
|
| -#endif
|
| -
|
| -// Harden the pointers stored in the TCMalloc linked lists
|
| -#if COMPILER(GCC)
|
| -#define ENABLE_TCMALLOC_HARDENING 1
|
| -#endif
|
| -
|
| -// Use a background thread to periodically scavenge memory to release back to the system
|
| -#define USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY 1
|
| -
|
| -#ifndef NDEBUG
|
| -namespace WTF {
|
| -
|
| -#if OS(WINDOWS)
|
| -
|
| -// TLS_OUT_OF_INDEXES is not defined on WinCE.
|
| -#ifndef TLS_OUT_OF_INDEXES
|
| -#define TLS_OUT_OF_INDEXES 0xffffffff
|
| -#endif
|
| -
|
| -static DWORD isForibiddenTlsIndex = TLS_OUT_OF_INDEXES;
|
| -static const LPVOID kTlsAllowValue = reinterpret_cast<LPVOID>(0); // Must be zero.
|
| -static const LPVOID kTlsForbiddenValue = reinterpret_cast<LPVOID>(1);
|
| -
|
| -#if !ASSERT_DISABLED
|
| -static bool isForbidden()
|
| -{
|
| - // By default, fastMalloc is allowed so we don't allocate the
|
| - // tls index unless we're asked to make it forbidden. If TlsSetValue
|
| - // has not been called on a thread, the value returned by TlsGetValue is 0.
|
| - return (isForibiddenTlsIndex != TLS_OUT_OF_INDEXES) && (TlsGetValue(isForibiddenTlsIndex) == kTlsForbiddenValue);
|
| -}
|
| -#endif
|
| -
|
| -void fastMallocForbid()
|
| -{
|
| - if (isForibiddenTlsIndex == TLS_OUT_OF_INDEXES)
|
| - isForibiddenTlsIndex = TlsAlloc(); // a little racey, but close enough for debug only
|
| - TlsSetValue(isForibiddenTlsIndex, kTlsForbiddenValue);
|
| -}
|
| -
|
| -void fastMallocAllow()
|
| -{
|
| - if (isForibiddenTlsIndex == TLS_OUT_OF_INDEXES)
|
| - return;
|
| - TlsSetValue(isForibiddenTlsIndex, kTlsAllowValue);
|
| -}
|
| -
|
| -#else // !OS(WINDOWS)
|
| -
|
| -static pthread_key_t isForbiddenKey;
|
| -static pthread_once_t isForbiddenKeyOnce = PTHREAD_ONCE_INIT;
|
| -static void initializeIsForbiddenKey()
|
| -{
|
| - pthread_key_create(&isForbiddenKey, 0);
|
| -}
|
| -
|
| -#if !ASSERT_DISABLED
|
| -static bool isForbidden()
|
| -{
|
| - pthread_once(&isForbiddenKeyOnce, initializeIsForbiddenKey);
|
| - return !!pthread_getspecific(isForbiddenKey);
|
| -}
|
| -#endif
|
| -
|
| -void fastMallocForbid()
|
| -{
|
| - pthread_once(&isForbiddenKeyOnce, initializeIsForbiddenKey);
|
| - pthread_setspecific(isForbiddenKey, &isForbiddenKey);
|
| -}
|
| -
|
| -void fastMallocAllow()
|
| -{
|
| - pthread_once(&isForbiddenKeyOnce, initializeIsForbiddenKey);
|
| - pthread_setspecific(isForbiddenKey, 0);
|
| -}
|
| -#endif // OS(WINDOWS)
|
| -
|
| -} // namespace WTF
|
| -#endif // NDEBUG
|
| -
|
| -namespace WTF {
|
| -
|
| -
|
| -namespace Internal {
|
| -#if !ENABLE(WTF_MALLOC_VALIDATION)
|
| -WTF_EXPORT_PRIVATE void fastMallocMatchFailed(void*);
|
| -#else
|
| -COMPILE_ASSERT(((sizeof(ValidationHeader) % sizeof(AllocAlignmentInteger)) == 0), ValidationHeader_must_produce_correct_alignment);
|
| -#endif
|
| -
|
| -NO_RETURN_DUE_TO_CRASH void fastMallocMatchFailed(void*)
|
| -{
|
| - CRASH();
|
| -}
|
| -
|
| -} // namespace Internal
|
| -
|
| -
|
| -void* fastZeroedMalloc(size_t n)
|
| -{
|
| - void* result = fastMalloc(n);
|
| - memset(result, 0, n);
|
| - return result;
|
| -}
|
| -
|
| -char* fastStrDup(const char* src)
|
| -{
|
| - size_t len = strlen(src) + 1;
|
| - char* dup = static_cast<char*>(fastMalloc(len));
|
| - memcpy(dup, src, len);
|
| - return dup;
|
| -}
|
| -
|
| -TryMallocReturnValue tryFastZeroedMalloc(size_t n)
|
| -{
|
| - void* result;
|
| - if (!tryFastMalloc(n).getValue(result))
|
| - return 0;
|
| - memset(result, 0, n);
|
| - return result;
|
| -}
|
| -
|
| -} // namespace WTF
|
| -
|
| -#if FORCE_SYSTEM_MALLOC
|
| -
|
| -#if OS(DARWIN)
|
| -#include <malloc/malloc.h>
|
| -#elif OS(WINDOWS)
|
| -#include <malloc.h>
|
| -#endif
|
| -
|
| -namespace WTF {
|
| -
|
| -size_t fastMallocGoodSize(size_t bytes)
|
| -{
|
| -#if OS(DARWIN)
|
| - return malloc_good_size(bytes);
|
| -#else
|
| - return bytes;
|
| -#endif
|
| -}
|
| -
|
| -TryMallocReturnValue tryFastMalloc(size_t n)
|
| -{
|
| - ASSERT(!isForbidden());
|
| -
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - if (std::numeric_limits<size_t>::max() - Internal::ValidationBufferSize <= n) // If overflow would occur...
|
| - return 0;
|
| -
|
| - void* result = malloc(n + Internal::ValidationBufferSize);
|
| - if (!result)
|
| - return 0;
|
| - Internal::ValidationHeader* header = static_cast<Internal::ValidationHeader*>(result);
|
| - header->m_size = n;
|
| - header->m_type = Internal::AllocTypeMalloc;
|
| - header->m_prefix = static_cast<unsigned>(Internal::ValidationPrefix);
|
| - result = header + 1;
|
| - *Internal::fastMallocValidationSuffix(result) = Internal::ValidationSuffix;
|
| - fastMallocValidate(result);
|
| - return result;
|
| -#else
|
| - return malloc(n);
|
| -#endif
|
| -}
|
| -
|
| -void* fastMalloc(size_t n)
|
| -{
|
| - ASSERT(!isForbidden());
|
| -
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - TryMallocReturnValue returnValue = tryFastMalloc(n);
|
| - void* result;
|
| - if (!returnValue.getValue(result))
|
| - CRASH();
|
| -#else
|
| - void* result = malloc(n);
|
| -#endif
|
| -
|
| - ASSERT(result); // We expect tcmalloc underneath, which would crash instead of getting here.
|
| -
|
| - return result;
|
| -}
|
| -
|
| -TryMallocReturnValue tryFastCalloc(size_t n_elements, size_t element_size)
|
| -{
|
| - ASSERT(!isForbidden());
|
| -
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - size_t totalBytes = n_elements * element_size;
|
| - if (n_elements > 1 && element_size && (totalBytes / element_size) != n_elements)
|
| - return 0;
|
| -
|
| - TryMallocReturnValue returnValue = tryFastMalloc(totalBytes);
|
| - void* result;
|
| - if (!returnValue.getValue(result))
|
| - return 0;
|
| - memset(result, 0, totalBytes);
|
| - fastMallocValidate(result);
|
| - return result;
|
| -#else
|
| - return calloc(n_elements, element_size);
|
| -#endif
|
| -}
|
| -
|
| -void* fastCalloc(size_t n_elements, size_t element_size)
|
| -{
|
| - ASSERT(!isForbidden());
|
| -
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - TryMallocReturnValue returnValue = tryFastCalloc(n_elements, element_size);
|
| - void* result;
|
| - if (!returnValue.getValue(result))
|
| - CRASH();
|
| -#else
|
| - void* result = calloc(n_elements, element_size);
|
| -#endif
|
| -
|
| - ASSERT(result); // We expect tcmalloc underneath, which would crash instead of getting here.
|
| -
|
| - return result;
|
| -}
|
| -
|
| -void fastFree(void* p)
|
| -{
|
| - ASSERT(!isForbidden());
|
| -
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - if (!p)
|
| - return;
|
| -
|
| - fastMallocMatchValidateFree(p, Internal::AllocTypeMalloc);
|
| - Internal::ValidationHeader* header = Internal::fastMallocValidationHeader(p);
|
| - memset(p, 0xCC, header->m_size);
|
| - free(header);
|
| -#else
|
| - free(p);
|
| -#endif
|
| -}
|
| -
|
| -TryMallocReturnValue tryFastRealloc(void* p, size_t n)
|
| -{
|
| - ASSERT(!isForbidden());
|
| -
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - if (p) {
|
| - if (std::numeric_limits<size_t>::max() - Internal::ValidationBufferSize <= n) // If overflow would occur...
|
| - return 0;
|
| - fastMallocValidate(p);
|
| - Internal::ValidationHeader* result = static_cast<Internal::ValidationHeader*>(realloc(Internal::fastMallocValidationHeader(p), n + Internal::ValidationBufferSize));
|
| - if (!result)
|
| - return 0;
|
| - result->m_size = n;
|
| - result = result + 1;
|
| - *fastMallocValidationSuffix(result) = Internal::ValidationSuffix;
|
| - fastMallocValidate(result);
|
| - return result;
|
| - } else {
|
| - return fastMalloc(n);
|
| - }
|
| -#else
|
| - return realloc(p, n);
|
| -#endif
|
| -}
|
| -
|
| -void* fastRealloc(void* p, size_t n)
|
| -{
|
| - ASSERT(!isForbidden());
|
| -
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - TryMallocReturnValue returnValue = tryFastRealloc(p, n);
|
| - void* result;
|
| - if (!returnValue.getValue(result))
|
| - CRASH();
|
| -#else
|
| - void* result = realloc(p, n);
|
| -#endif
|
| -
|
| - ASSERT(result); // We expect tcmalloc underneath, which would crash instead of getting here.
|
| -
|
| - return result;
|
| -}
|
| -
|
| -void releaseFastMallocFreeMemory() { }
|
| -
|
| -FastMallocStatistics fastMallocStatistics()
|
| -{
|
| - FastMallocStatistics statistics = { 0, 0, 0 };
|
| - return statistics;
|
| -}
|
| -
|
| -size_t fastMallocSize(const void* p)
|
| -{
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - return Internal::fastMallocValidationHeader(const_cast<void*>(p))->m_size;
|
| -#elif OS(DARWIN)
|
| - return malloc_size(p);
|
| -#elif OS(WINDOWS)
|
| - return _msize(const_cast<void*>(p));
|
| -#else
|
| - UNUSED_PARAM(p);
|
| - return 1;
|
| -#endif
|
| -}
|
| -
|
| -} // namespace WTF
|
| -
|
| -#if OS(DARWIN)
|
| -// This symbol is present in the JavaScriptCore exports file even when FastMalloc is disabled.
|
| -// It will never be used in this case, so it's type and value are less interesting than its presence.
|
| -extern "C" WTF_EXPORT_PRIVATE const int jscore_fastmalloc_introspection = 0;
|
| -#endif
|
| -
|
| -#else // FORCE_SYSTEM_MALLOC
|
| -
|
| -#include "Compiler.h"
|
| -#include "TCPackedCache.h"
|
| -#include "TCPageMap.h"
|
| -#include "TCSpinLock.h"
|
| -#include "TCSystemAlloc.h"
|
| -#include <algorithm>
|
| -#include <pthread.h>
|
| -#include <stdarg.h>
|
| -#include <stddef.h>
|
| -#include <stdint.h>
|
| -#include <stdio.h>
|
| -#if HAVE(ERRNO_H)
|
| -#include <errno.h>
|
| -#endif
|
| -#if OS(UNIX)
|
| -#include <unistd.h>
|
| -#endif
|
| -#if OS(WINDOWS)
|
| -#ifndef WIN32_LEAN_AND_MEAN
|
| -#define WIN32_LEAN_AND_MEAN
|
| -#endif
|
| -#include <windows.h>
|
| -#endif
|
| -
|
| -#ifdef WTF_CHANGES
|
| -
|
| -#if OS(DARWIN)
|
| -#include "MallocZoneSupport.h"
|
| -#include <wtf/HashSet.h>
|
| -#include <wtf/Vector.h>
|
| -#endif
|
| -
|
| -#if HAVE(DISPATCH_H)
|
| -#include <dispatch/dispatch.h>
|
| -#endif
|
| -
|
| -#ifdef __has_include
|
| -#if __has_include(<System/pthread_machdep.h>)
|
| -
|
| -#include <System/pthread_machdep.h>
|
| -
|
| -#if defined(__PTK_FRAMEWORK_JAVASCRIPTCORE_KEY0)
|
| -#define WTF_USE_PTHREAD_GETSPECIFIC_DIRECT 1
|
| -#endif
|
| -
|
| -#endif
|
| -#endif
|
| -
|
| -#ifndef PRIuS
|
| -#define PRIuS "zu"
|
| -#endif
|
| -
|
| -// Calling pthread_getspecific through a global function pointer is faster than a normal
|
| -// call to the function on Mac OS X, and it's used in performance-critical code. So we
|
| -// use a function pointer. But that's not necessarily faster on other platforms, and we had
|
| -// problems with this technique on Windows, so we'll do this only on Mac OS X.
|
| -#if OS(DARWIN)
|
| -#if !USE(PTHREAD_GETSPECIFIC_DIRECT)
|
| -static void* (*pthread_getspecific_function_pointer)(pthread_key_t) = pthread_getspecific;
|
| -#define pthread_getspecific(key) pthread_getspecific_function_pointer(key)
|
| -#else
|
| -#define pthread_getspecific(key) _pthread_getspecific_direct(key)
|
| -#define pthread_setspecific(key, val) _pthread_setspecific_direct(key, (val))
|
| -#endif
|
| -#endif
|
| -
|
| -#define DEFINE_VARIABLE(type, name, value, meaning) \
|
| - namespace FLAG__namespace_do_not_use_directly_use_DECLARE_##type##_instead { \
|
| - type FLAGS_##name(value); \
|
| - char FLAGS_no##name; \
|
| - } \
|
| - using FLAG__namespace_do_not_use_directly_use_DECLARE_##type##_instead::FLAGS_##name
|
| -
|
| -#define DEFINE_int64(name, value, meaning) \
|
| - DEFINE_VARIABLE(int64_t, name, value, meaning)
|
| -
|
| -#define DEFINE_double(name, value, meaning) \
|
| - DEFINE_VARIABLE(double, name, value, meaning)
|
| -
|
| -namespace WTF {
|
| -
|
| -#define malloc fastMalloc
|
| -#define calloc fastCalloc
|
| -#define free fastFree
|
| -#define realloc fastRealloc
|
| -
|
| -#define MESSAGE LOG_ERROR
|
| -#define CHECK_CONDITION ASSERT
|
| -
|
| -static const char kLLHardeningMask = 0;
|
| -template <unsigned> struct EntropySource;
|
| -template <> struct EntropySource<4> {
|
| - static uint32_t value()
|
| - {
|
| -#if OS(DARWIN)
|
| - return arc4random();
|
| -#else
|
| - return static_cast<uint32_t>(static_cast<uintptr_t>(currentTime() * 10000) ^ reinterpret_cast<uintptr_t>(&kLLHardeningMask));
|
| -#endif
|
| - }
|
| -};
|
| -
|
| -template <> struct EntropySource<8> {
|
| - static uint64_t value()
|
| - {
|
| - return EntropySource<4>::value() | (static_cast<uint64_t>(EntropySource<4>::value()) << 32);
|
| - }
|
| -};
|
| -
|
| -#if ENABLE(TCMALLOC_HARDENING)
|
| -/*
|
| - * To make it harder to exploit use-after free style exploits
|
| - * we mask the addresses we put into our linked lists with the
|
| - * address of kLLHardeningMask. Due to ASLR the address of
|
| - * kLLHardeningMask should be sufficiently randomized to make direct
|
| - * freelist manipulation much more difficult.
|
| - */
|
| -enum {
|
| - MaskKeyShift = 13
|
| -};
|
| -
|
| -static ALWAYS_INLINE uintptr_t internalEntropyValue()
|
| -{
|
| - static uintptr_t value = EntropySource<sizeof(uintptr_t)>::value() | 1;
|
| - ASSERT(value);
|
| - return value;
|
| -}
|
| -
|
| -#define HARDENING_ENTROPY internalEntropyValue()
|
| -#define ROTATE_VALUE(value, amount) (((value) >> (amount)) | ((value) << (sizeof(value) * 8 - (amount))))
|
| -#define XOR_MASK_PTR_WITH_KEY(ptr, key, entropy) (reinterpret_cast<typeof(ptr)>(reinterpret_cast<uintptr_t>(ptr)^(ROTATE_VALUE(reinterpret_cast<uintptr_t>(key), MaskKeyShift)^entropy)))
|
| -
|
| -
|
| -static ALWAYS_INLINE uint32_t freedObjectStartPoison()
|
| -{
|
| - static uint32_t value = EntropySource<sizeof(uint32_t)>::value() | 1;
|
| - ASSERT(value);
|
| - return value;
|
| -}
|
| -
|
| -static ALWAYS_INLINE uint32_t freedObjectEndPoison()
|
| -{
|
| - static uint32_t value = EntropySource<sizeof(uint32_t)>::value() | 1;
|
| - ASSERT(value);
|
| - return value;
|
| -}
|
| -
|
| -#define PTR_TO_UINT32(ptr) static_cast<uint32_t>(reinterpret_cast<uintptr_t>(ptr))
|
| -#define END_POISON_INDEX(allocationSize) (((allocationSize) - sizeof(uint32_t)) / sizeof(uint32_t))
|
| -#define POISON_ALLOCATION(allocation, allocationSize) do { \
|
| - ASSERT((allocationSize) >= 2 * sizeof(uint32_t)); \
|
| - reinterpret_cast<uint32_t*>(allocation)[0] = 0xbadbeef1; \
|
| - reinterpret_cast<uint32_t*>(allocation)[1] = 0xbadbeef3; \
|
| - if ((allocationSize) < 4 * sizeof(uint32_t)) \
|
| - break; \
|
| - reinterpret_cast<uint32_t*>(allocation)[2] = 0xbadbeef5; \
|
| - reinterpret_cast<uint32_t*>(allocation)[END_POISON_INDEX(allocationSize)] = 0xbadbeef7; \
|
| -} while (false);
|
| -
|
| -#define POISON_DEALLOCATION_EXPLICIT(allocation, allocationSize, startPoison, endPoison) do { \
|
| - ASSERT((allocationSize) >= 2 * sizeof(uint32_t)); \
|
| - reinterpret_cast<uint32_t*>(allocation)[0] = 0xbadbeef9; \
|
| - reinterpret_cast<uint32_t*>(allocation)[1] = 0xbadbeefb; \
|
| - if ((allocationSize) < 4 * sizeof(uint32_t)) \
|
| - break; \
|
| - reinterpret_cast<uint32_t*>(allocation)[2] = (startPoison) ^ PTR_TO_UINT32(allocation); \
|
| - reinterpret_cast<uint32_t*>(allocation)[END_POISON_INDEX(allocationSize)] = (endPoison) ^ PTR_TO_UINT32(allocation); \
|
| -} while (false)
|
| -
|
| -#define POISON_DEALLOCATION(allocation, allocationSize) \
|
| - POISON_DEALLOCATION_EXPLICIT(allocation, (allocationSize), freedObjectStartPoison(), freedObjectEndPoison())
|
| -
|
| -#define MAY_BE_POISONED(allocation, allocationSize) (((allocationSize) >= 4 * sizeof(uint32_t)) && ( \
|
| - (reinterpret_cast<uint32_t*>(allocation)[2] == (freedObjectStartPoison() ^ PTR_TO_UINT32(allocation))) || \
|
| - (reinterpret_cast<uint32_t*>(allocation)[END_POISON_INDEX(allocationSize)] == (freedObjectEndPoison() ^ PTR_TO_UINT32(allocation))) \
|
| -))
|
| -
|
| -#define IS_DEFINITELY_POISONED(allocation, allocationSize) (((allocationSize) < 4 * sizeof(uint32_t)) || ( \
|
| - (reinterpret_cast<uint32_t*>(allocation)[2] == (freedObjectStartPoison() ^ PTR_TO_UINT32(allocation))) && \
|
| - (reinterpret_cast<uint32_t*>(allocation)[END_POISON_INDEX(allocationSize)] == (freedObjectEndPoison() ^ PTR_TO_UINT32(allocation))) \
|
| -))
|
| -
|
| -#else
|
| -
|
| -#define POISON_ALLOCATION(allocation, allocationSize)
|
| -#define POISON_DEALLOCATION(allocation, allocationSize)
|
| -#define POISON_DEALLOCATION_EXPLICIT(allocation, allocationSize, startPoison, endPoison)
|
| -#define MAY_BE_POISONED(allocation, allocationSize) (false)
|
| -#define IS_DEFINITELY_POISONED(allocation, allocationSize) (true)
|
| -#define XOR_MASK_PTR_WITH_KEY(ptr, key, entropy) (((void)entropy), ((void)key), ptr)
|
| -
|
| -#define HARDENING_ENTROPY 0
|
| -
|
| -#endif
|
| -
|
| -//-------------------------------------------------------------------
|
| -// Configuration
|
| -//-------------------------------------------------------------------
|
| -
|
| -// Not all possible combinations of the following parameters make
|
| -// sense. In particular, if kMaxSize increases, you may have to
|
| -// increase kNumClasses as well.
|
| -static const size_t kPageShift = 12;
|
| -static const size_t kPageSize = 1 << kPageShift;
|
| -static const size_t kMaxSize = 8u * kPageSize;
|
| -static const size_t kAlignShift = 3;
|
| -static const size_t kAlignment = 1 << kAlignShift;
|
| -static const size_t kNumClasses = 68;
|
| -
|
| -// Allocates a big block of memory for the pagemap once we reach more than
|
| -// 128MB
|
| -static const size_t kPageMapBigAllocationThreshold = 128 << 20;
|
| -
|
| -// Minimum number of pages to fetch from system at a time. Must be
|
| -// significantly bigger than kPageSize to amortize system-call
|
| -// overhead, and also to reduce external fragementation. Also, we
|
| -// should keep this value big because various incarnations of Linux
|
| -// have small limits on the number of mmap() regions per
|
| -// address-space.
|
| -static const size_t kMinSystemAlloc = 1 << (20 - kPageShift);
|
| -
|
| -// Number of objects to move between a per-thread list and a central
|
| -// list in one shot. We want this to be not too small so we can
|
| -// amortize the lock overhead for accessing the central list. Making
|
| -// it too big may temporarily cause unnecessary memory wastage in the
|
| -// per-thread free list until the scavenger cleans up the list.
|
| -static int num_objects_to_move[kNumClasses];
|
| -
|
| -// Maximum length we allow a per-thread free-list to have before we
|
| -// move objects from it into the corresponding central free-list. We
|
| -// want this big to avoid locking the central free-list too often. It
|
| -// should not hurt to make this list somewhat big because the
|
| -// scavenging code will shrink it down when its contents are not in use.
|
| -static const int kMaxFreeListLength = 256;
|
| -
|
| -// Lower and upper bounds on the per-thread cache sizes
|
| -static const size_t kMinThreadCacheSize = kMaxSize * 2;
|
| -static const size_t kMaxThreadCacheSize = 2 << 20;
|
| -
|
| -// Default bound on the total amount of thread caches
|
| -static const size_t kDefaultOverallThreadCacheSize = 16 << 20;
|
| -
|
| -// For all span-lengths < kMaxPages we keep an exact-size list.
|
| -// REQUIRED: kMaxPages >= kMinSystemAlloc;
|
| -static const size_t kMaxPages = kMinSystemAlloc;
|
| -
|
| -/* The smallest prime > 2^n */
|
| -static int primes_list[] = {
|
| - // Small values might cause high rates of sampling
|
| - // and hence commented out.
|
| - // 2, 5, 11, 17, 37, 67, 131, 257,
|
| - // 521, 1031, 2053, 4099, 8209, 16411,
|
| - 32771, 65537, 131101, 262147, 524309, 1048583,
|
| - 2097169, 4194319, 8388617, 16777259, 33554467 };
|
| -
|
| -// Twice the approximate gap between sampling actions.
|
| -// I.e., we take one sample approximately once every
|
| -// tcmalloc_sample_parameter/2
|
| -// bytes of allocation, i.e., ~ once every 128KB.
|
| -// Must be a prime number.
|
| -#ifdef NO_TCMALLOC_SAMPLES
|
| -DEFINE_int64(tcmalloc_sample_parameter, 0,
|
| - "Unused: code is compiled with NO_TCMALLOC_SAMPLES");
|
| -static size_t sample_period = 0;
|
| -#else
|
| -DEFINE_int64(tcmalloc_sample_parameter, 262147,
|
| - "Twice the approximate gap between sampling actions."
|
| - " Must be a prime number. Otherwise will be rounded up to a "
|
| - " larger prime number");
|
| -static size_t sample_period = 262147;
|
| -#endif
|
| -
|
| -// Protects sample_period above
|
| -static SpinLock sample_period_lock = SPINLOCK_INITIALIZER;
|
| -
|
| -// Parameters for controlling how fast memory is returned to the OS.
|
| -
|
| -DEFINE_double(tcmalloc_release_rate, 1,
|
| - "Rate at which we release unused memory to the system. "
|
| - "Zero means we never release memory back to the system. "
|
| - "Increase this flag to return memory faster; decrease it "
|
| - "to return memory slower. Reasonable rates are in the "
|
| - "range [0,10]");
|
| -
|
| -//-------------------------------------------------------------------
|
| -// Mapping from size to size_class and vice versa
|
| -//-------------------------------------------------------------------
|
| -
|
| -// Sizes <= 1024 have an alignment >= 8. So for such sizes we have an
|
| -// array indexed by ceil(size/8). Sizes > 1024 have an alignment >= 128.
|
| -// So for these larger sizes we have an array indexed by ceil(size/128).
|
| -//
|
| -// We flatten both logical arrays into one physical array and use
|
| -// arithmetic to compute an appropriate index. The constants used by
|
| -// ClassIndex() were selected to make the flattening work.
|
| -//
|
| -// Examples:
|
| -// Size Expression Index
|
| -// -------------------------------------------------------
|
| -// 0 (0 + 7) / 8 0
|
| -// 1 (1 + 7) / 8 1
|
| -// ...
|
| -// 1024 (1024 + 7) / 8 128
|
| -// 1025 (1025 + 127 + (120<<7)) / 128 129
|
| -// ...
|
| -// 32768 (32768 + 127 + (120<<7)) / 128 376
|
| -static const size_t kMaxSmallSize = 1024;
|
| -static const int shift_amount[2] = { 3, 7 }; // For divides by 8 or 128
|
| -static const int add_amount[2] = { 7, 127 + (120 << 7) };
|
| -static unsigned char class_array[377];
|
| -
|
| -// Compute index of the class_array[] entry for a given size
|
| -static inline int ClassIndex(size_t s) {
|
| - const int i = (s > kMaxSmallSize);
|
| - return static_cast<int>((s + add_amount[i]) >> shift_amount[i]);
|
| -}
|
| -
|
| -// Mapping from size class to max size storable in that class
|
| -static size_t class_to_size[kNumClasses];
|
| -
|
| -// Mapping from size class to number of pages to allocate at a time
|
| -static size_t class_to_pages[kNumClasses];
|
| -
|
| -// Hardened singly linked list. We make this a class to allow compiler to
|
| -// statically prevent mismatching hardened and non-hardened list
|
| -class HardenedSLL {
|
| -public:
|
| - static ALWAYS_INLINE HardenedSLL create(void* value)
|
| - {
|
| - HardenedSLL result;
|
| - result.m_value = value;
|
| - return result;
|
| - }
|
| -
|
| - static ALWAYS_INLINE HardenedSLL null()
|
| - {
|
| - HardenedSLL result;
|
| - result.m_value = 0;
|
| - return result;
|
| - }
|
| -
|
| - ALWAYS_INLINE void setValue(void* value) { m_value = value; }
|
| - ALWAYS_INLINE void* value() const { return m_value; }
|
| - ALWAYS_INLINE bool operator!() const { return !m_value; }
|
| - typedef void* (HardenedSLL::*UnspecifiedBoolType);
|
| - ALWAYS_INLINE operator UnspecifiedBoolType() const { return m_value ? &HardenedSLL::m_value : 0; }
|
| -
|
| - bool operator!=(const HardenedSLL& other) const { return m_value != other.m_value; }
|
| - bool operator==(const HardenedSLL& other) const { return m_value == other.m_value; }
|
| -
|
| -private:
|
| - void* m_value;
|
| -};
|
| -
|
| -// TransferCache is used to cache transfers of num_objects_to_move[size_class]
|
| -// back and forth between thread caches and the central cache for a given size
|
| -// class.
|
| -struct TCEntry {
|
| - HardenedSLL head; // Head of chain of objects.
|
| - HardenedSLL tail; // Tail of chain of objects.
|
| -};
|
| -// A central cache freelist can have anywhere from 0 to kNumTransferEntries
|
| -// slots to put link list chains into. To keep memory usage bounded the total
|
| -// number of TCEntries across size classes is fixed. Currently each size
|
| -// class is initially given one TCEntry which also means that the maximum any
|
| -// one class can have is kNumClasses.
|
| -static const int kNumTransferEntries = kNumClasses;
|
| -
|
| -// Note: the following only works for "n"s that fit in 32-bits, but
|
| -// that is fine since we only use it for small sizes.
|
| -static inline int LgFloor(size_t n) {
|
| - int log = 0;
|
| - for (int i = 4; i >= 0; --i) {
|
| - int shift = (1 << i);
|
| - size_t x = n >> shift;
|
| - if (x != 0) {
|
| - n = x;
|
| - log += shift;
|
| - }
|
| - }
|
| - ASSERT(n == 1);
|
| - return log;
|
| -}
|
| -
|
| -// Functions for using our simple hardened singly linked list
|
| -static ALWAYS_INLINE HardenedSLL SLL_Next(HardenedSLL t, uintptr_t entropy) {
|
| - return HardenedSLL::create(XOR_MASK_PTR_WITH_KEY(*(reinterpret_cast<void**>(t.value())), t.value(), entropy));
|
| -}
|
| -
|
| -static ALWAYS_INLINE void SLL_SetNext(HardenedSLL t, HardenedSLL n, uintptr_t entropy) {
|
| - *(reinterpret_cast<void**>(t.value())) = XOR_MASK_PTR_WITH_KEY(n.value(), t.value(), entropy);
|
| -}
|
| -
|
| -static ALWAYS_INLINE void SLL_Push(HardenedSLL* list, HardenedSLL element, uintptr_t entropy) {
|
| - SLL_SetNext(element, *list, entropy);
|
| - *list = element;
|
| -}
|
| -
|
| -static ALWAYS_INLINE HardenedSLL SLL_Pop(HardenedSLL *list, uintptr_t entropy) {
|
| - HardenedSLL result = *list;
|
| - *list = SLL_Next(*list, entropy);
|
| - return result;
|
| -}
|
| -
|
| -// Remove N elements from a linked list to which head points. head will be
|
| -// modified to point to the new head. start and end will point to the first
|
| -// and last nodes of the range. Note that end will point to NULL after this
|
| -// function is called.
|
| -
|
| -static ALWAYS_INLINE void SLL_PopRange(HardenedSLL* head, int N, HardenedSLL *start, HardenedSLL *end, uintptr_t entropy) {
|
| - if (N == 0) {
|
| - *start = HardenedSLL::null();
|
| - *end = HardenedSLL::null();
|
| - return;
|
| - }
|
| -
|
| - HardenedSLL tmp = *head;
|
| - for (int i = 1; i < N; ++i) {
|
| - tmp = SLL_Next(tmp, entropy);
|
| - }
|
| -
|
| - *start = *head;
|
| - *end = tmp;
|
| - *head = SLL_Next(tmp, entropy);
|
| - // Unlink range from list.
|
| - SLL_SetNext(tmp, HardenedSLL::null(), entropy);
|
| -}
|
| -
|
| -static ALWAYS_INLINE void SLL_PushRange(HardenedSLL *head, HardenedSLL start, HardenedSLL end, uintptr_t entropy) {
|
| - if (!start) return;
|
| - SLL_SetNext(end, *head, entropy);
|
| - *head = start;
|
| -}
|
| -
|
| -static ALWAYS_INLINE size_t SLL_Size(HardenedSLL head, uintptr_t entropy) {
|
| - int count = 0;
|
| - while (head) {
|
| - count++;
|
| - head = SLL_Next(head, entropy);
|
| - }
|
| - return count;
|
| -}
|
| -
|
| -// Setup helper functions.
|
| -
|
| -static ALWAYS_INLINE size_t SizeClass(size_t size) {
|
| - return class_array[ClassIndex(size)];
|
| -}
|
| -
|
| -// Get the byte-size for a specified class
|
| -static ALWAYS_INLINE size_t ByteSizeForClass(size_t cl) {
|
| - return class_to_size[cl];
|
| -}
|
| -static int NumMoveSize(size_t size) {
|
| - if (size == 0) return 0;
|
| - // Use approx 64k transfers between thread and central caches.
|
| - int num = static_cast<int>(64.0 * 1024.0 / size);
|
| - if (num < 2) num = 2;
|
| - // Clamp well below kMaxFreeListLength to avoid ping pong between central
|
| - // and thread caches.
|
| - if (num > static_cast<int>(0.8 * kMaxFreeListLength))
|
| - num = static_cast<int>(0.8 * kMaxFreeListLength);
|
| -
|
| - // Also, avoid bringing in too many objects into small object free
|
| - // lists. There are lots of such lists, and if we allow each one to
|
| - // fetch too many at a time, we end up having to scavenge too often
|
| - // (especially when there are lots of threads and each thread gets a
|
| - // small allowance for its thread cache).
|
| - //
|
| - // TODO: Make thread cache free list sizes dynamic so that we do not
|
| - // have to equally divide a fixed resource amongst lots of threads.
|
| - if (num > 32) num = 32;
|
| -
|
| - return num;
|
| -}
|
| -
|
| -// Initialize the mapping arrays
|
| -static void InitSizeClasses() {
|
| - // Do some sanity checking on add_amount[]/shift_amount[]/class_array[]
|
| - if (ClassIndex(0) < 0) {
|
| - MESSAGE("Invalid class index %d for size 0\n", ClassIndex(0));
|
| - CRASH();
|
| - }
|
| - if (static_cast<size_t>(ClassIndex(kMaxSize)) >= sizeof(class_array)) {
|
| - MESSAGE("Invalid class index %d for kMaxSize\n", ClassIndex(kMaxSize));
|
| - CRASH();
|
| - }
|
| -
|
| - // Compute the size classes we want to use
|
| - size_t sc = 1; // Next size class to assign
|
| - unsigned char alignshift = kAlignShift;
|
| - int last_lg = -1;
|
| - for (size_t size = kAlignment; size <= kMaxSize; size += (1 << alignshift)) {
|
| - int lg = LgFloor(size);
|
| - if (lg > last_lg) {
|
| - // Increase alignment every so often.
|
| - //
|
| - // Since we double the alignment every time size doubles and
|
| - // size >= 128, this means that space wasted due to alignment is
|
| - // at most 16/128 i.e., 12.5%. Plus we cap the alignment at 256
|
| - // bytes, so the space wasted as a percentage starts falling for
|
| - // sizes > 2K.
|
| - if ((lg >= 7) && (alignshift < 8)) {
|
| - alignshift++;
|
| - }
|
| - last_lg = lg;
|
| - }
|
| -
|
| - // Allocate enough pages so leftover is less than 1/8 of total.
|
| - // This bounds wasted space to at most 12.5%.
|
| - size_t psize = kPageSize;
|
| - while ((psize % size) > (psize >> 3)) {
|
| - psize += kPageSize;
|
| - }
|
| - const size_t my_pages = psize >> kPageShift;
|
| -
|
| - if (sc > 1 && my_pages == class_to_pages[sc-1]) {
|
| - // See if we can merge this into the previous class without
|
| - // increasing the fragmentation of the previous class.
|
| - const size_t my_objects = (my_pages << kPageShift) / size;
|
| - const size_t prev_objects = (class_to_pages[sc-1] << kPageShift)
|
| - / class_to_size[sc-1];
|
| - if (my_objects == prev_objects) {
|
| - // Adjust last class to include this size
|
| - class_to_size[sc-1] = size;
|
| - continue;
|
| - }
|
| - }
|
| -
|
| - // Add new class
|
| - class_to_pages[sc] = my_pages;
|
| - class_to_size[sc] = size;
|
| - sc++;
|
| - }
|
| - if (sc != kNumClasses) {
|
| - MESSAGE("wrong number of size classes: found %" PRIuS " instead of %d\n",
|
| - sc, int(kNumClasses));
|
| - CRASH();
|
| - }
|
| -
|
| - // Initialize the mapping arrays
|
| - int next_size = 0;
|
| - for (unsigned char c = 1; c < kNumClasses; c++) {
|
| - const size_t max_size_in_class = class_to_size[c];
|
| - for (size_t s = next_size; s <= max_size_in_class; s += kAlignment) {
|
| - class_array[ClassIndex(s)] = c;
|
| - }
|
| - next_size = static_cast<int>(max_size_in_class + kAlignment);
|
| - }
|
| -
|
| - // Double-check sizes just to be safe
|
| - for (size_t size = 0; size <= kMaxSize; size++) {
|
| - const size_t sc = SizeClass(size);
|
| - if (sc == 0) {
|
| - MESSAGE("Bad size class %" PRIuS " for %" PRIuS "\n", sc, size);
|
| - CRASH();
|
| - }
|
| - if (sc > 1 && size <= class_to_size[sc-1]) {
|
| - MESSAGE("Allocating unnecessarily large class %" PRIuS " for %" PRIuS
|
| - "\n", sc, size);
|
| - CRASH();
|
| - }
|
| - if (sc >= kNumClasses) {
|
| - MESSAGE("Bad size class %" PRIuS " for %" PRIuS "\n", sc, size);
|
| - CRASH();
|
| - }
|
| - const size_t s = class_to_size[sc];
|
| - if (size > s) {
|
| - MESSAGE("Bad size %" PRIuS " for %" PRIuS " (sc = %" PRIuS ")\n", s, size, sc);
|
| - CRASH();
|
| - }
|
| - if (s == 0) {
|
| - MESSAGE("Bad size %" PRIuS " for %" PRIuS " (sc = %" PRIuS ")\n", s, size, sc);
|
| - CRASH();
|
| - }
|
| - }
|
| -
|
| - // Initialize the num_objects_to_move array.
|
| - for (size_t cl = 1; cl < kNumClasses; ++cl) {
|
| - num_objects_to_move[cl] = NumMoveSize(ByteSizeForClass(cl));
|
| - }
|
| -
|
| -#ifndef WTF_CHANGES
|
| - if (false) {
|
| - // Dump class sizes and maximum external wastage per size class
|
| - for (size_t cl = 1; cl < kNumClasses; ++cl) {
|
| - const int alloc_size = class_to_pages[cl] << kPageShift;
|
| - const int alloc_objs = alloc_size / class_to_size[cl];
|
| - const int min_used = (class_to_size[cl-1] + 1) * alloc_objs;
|
| - const int max_waste = alloc_size - min_used;
|
| - MESSAGE("SC %3d [ %8d .. %8d ] from %8d ; %2.0f%% maxwaste\n",
|
| - int(cl),
|
| - int(class_to_size[cl-1] + 1),
|
| - int(class_to_size[cl]),
|
| - int(class_to_pages[cl] << kPageShift),
|
| - max_waste * 100.0 / alloc_size
|
| - );
|
| - }
|
| - }
|
| -#endif
|
| -}
|
| -
|
| -// -------------------------------------------------------------------------
|
| -// Simple allocator for objects of a specified type. External locking
|
| -// is required before accessing one of these objects.
|
| -// -------------------------------------------------------------------------
|
| -
|
| -// Metadata allocator -- keeps stats about how many bytes allocated
|
| -static uint64_t metadata_system_bytes = 0;
|
| -static void* MetaDataAlloc(size_t bytes) {
|
| - void* result = TCMalloc_SystemAlloc(bytes, 0);
|
| - if (result != NULL) {
|
| - metadata_system_bytes += bytes;
|
| - }
|
| - return result;
|
| -}
|
| -
|
| -template <class T>
|
| -class PageHeapAllocator {
|
| - private:
|
| - // How much to allocate from system at a time
|
| - static const size_t kAllocIncrement = 32 << 10;
|
| -
|
| - // Aligned size of T
|
| - static const size_t kAlignedSize
|
| - = (((sizeof(T) + kAlignment - 1) / kAlignment) * kAlignment);
|
| -
|
| - // Free area from which to carve new objects
|
| - char* free_area_;
|
| - size_t free_avail_;
|
| -
|
| - // Linked list of all regions allocated by this allocator
|
| - HardenedSLL allocated_regions_;
|
| -
|
| - // Free list of already carved objects
|
| - HardenedSLL free_list_;
|
| -
|
| - // Number of allocated but unfreed objects
|
| - int inuse_;
|
| - uintptr_t entropy_;
|
| -
|
| - public:
|
| - void Init(uintptr_t entropy) {
|
| - ASSERT(kAlignedSize <= kAllocIncrement);
|
| - inuse_ = 0;
|
| - allocated_regions_ = HardenedSLL::null();
|
| - free_area_ = NULL;
|
| - free_avail_ = 0;
|
| - free_list_.setValue(NULL);
|
| - entropy_ = entropy;
|
| - }
|
| -
|
| - T* New() {
|
| - // Consult free list
|
| - void* result;
|
| - if (free_list_) {
|
| - result = free_list_.value();
|
| - free_list_ = SLL_Next(free_list_, entropy_);
|
| - } else {
|
| - if (free_avail_ < kAlignedSize) {
|
| - // Need more room
|
| - char* new_allocation = reinterpret_cast<char*>(MetaDataAlloc(kAllocIncrement));
|
| - if (!new_allocation)
|
| - CRASH();
|
| -
|
| - HardenedSLL new_head = HardenedSLL::create(new_allocation);
|
| - SLL_SetNext(new_head, allocated_regions_, entropy_);
|
| - allocated_regions_ = new_head;
|
| - free_area_ = new_allocation + kAlignedSize;
|
| - free_avail_ = kAllocIncrement - kAlignedSize;
|
| - }
|
| - result = free_area_;
|
| - free_area_ += kAlignedSize;
|
| - free_avail_ -= kAlignedSize;
|
| - }
|
| - inuse_++;
|
| - return reinterpret_cast<T*>(result);
|
| - }
|
| -
|
| - void Delete(T* p) {
|
| - HardenedSLL new_head = HardenedSLL::create(p);
|
| - SLL_SetNext(new_head, free_list_, entropy_);
|
| - free_list_ = new_head;
|
| - inuse_--;
|
| - }
|
| -
|
| - int inuse() const { return inuse_; }
|
| -
|
| -#if defined(WTF_CHANGES) && OS(DARWIN)
|
| - template <class Recorder>
|
| - void recordAdministrativeRegions(Recorder& recorder, const RemoteMemoryReader& reader)
|
| - {
|
| - for (HardenedSLL adminAllocation = allocated_regions_; adminAllocation; adminAllocation.setValue(reader.nextEntryInHardenedLinkedList(reinterpret_cast<void**>(adminAllocation.value()), entropy_)))
|
| - recorder.recordRegion(reinterpret_cast<vm_address_t>(adminAllocation.value()), kAllocIncrement);
|
| - }
|
| -#endif
|
| -};
|
| -
|
| -// -------------------------------------------------------------------------
|
| -// Span - a contiguous run of pages
|
| -// -------------------------------------------------------------------------
|
| -
|
| -// Type that can hold a page number
|
| -typedef uintptr_t PageID;
|
| -
|
| -// Type that can hold the length of a run of pages
|
| -typedef uintptr_t Length;
|
| -
|
| -static const Length kMaxValidPages = (~static_cast<Length>(0)) >> kPageShift;
|
| -
|
| -// Convert byte size into pages. This won't overflow, but may return
|
| -// an unreasonably large value if bytes is huge enough.
|
| -static inline Length pages(size_t bytes) {
|
| - return (bytes >> kPageShift) +
|
| - ((bytes & (kPageSize - 1)) > 0 ? 1 : 0);
|
| -}
|
| -
|
| -// Convert a user size into the number of bytes that will actually be
|
| -// allocated
|
| -static size_t AllocationSize(size_t bytes) {
|
| - if (bytes > kMaxSize) {
|
| - // Large object: we allocate an integral number of pages
|
| - ASSERT(bytes <= (kMaxValidPages << kPageShift));
|
| - return pages(bytes) << kPageShift;
|
| - } else {
|
| - // Small object: find the size class to which it belongs
|
| - return ByteSizeForClass(SizeClass(bytes));
|
| - }
|
| -}
|
| -
|
| -enum {
|
| - kSpanCookieBits = 10,
|
| - kSpanCookieMask = (1 << 10) - 1,
|
| - kSpanThisShift = 7
|
| -};
|
| -
|
| -static uint32_t spanValidationCookie;
|
| -static uint32_t spanInitializerCookie()
|
| -{
|
| - static uint32_t value = EntropySource<sizeof(uint32_t)>::value() & kSpanCookieMask;
|
| - spanValidationCookie = value;
|
| - return value;
|
| -}
|
| -
|
| -// Information kept for a span (a contiguous run of pages).
|
| -struct Span {
|
| - PageID start; // Starting page number
|
| - Length length; // Number of pages in span
|
| - Span* next(uintptr_t entropy) const { return XOR_MASK_PTR_WITH_KEY(m_next, this, entropy); }
|
| - Span* remoteNext(const Span* remoteSpanPointer, uintptr_t entropy) const { return XOR_MASK_PTR_WITH_KEY(m_next, remoteSpanPointer, entropy); }
|
| - Span* prev(uintptr_t entropy) const { return XOR_MASK_PTR_WITH_KEY(m_prev, this, entropy); }
|
| - void setNext(Span* next, uintptr_t entropy) { m_next = XOR_MASK_PTR_WITH_KEY(next, this, entropy); }
|
| - void setPrev(Span* prev, uintptr_t entropy) { m_prev = XOR_MASK_PTR_WITH_KEY(prev, this, entropy); }
|
| -
|
| -private:
|
| - Span* m_next; // Used when in link list
|
| - Span* m_prev; // Used when in link list
|
| -public:
|
| - HardenedSLL objects; // Linked list of free objects
|
| - unsigned int free : 1; // Is the span free
|
| -#ifndef NO_TCMALLOC_SAMPLES
|
| - unsigned int sample : 1; // Sampled object?
|
| -#endif
|
| - unsigned int sizeclass : 8; // Size-class for small objects (or 0)
|
| - unsigned int refcount : 11; // Number of non-free objects
|
| - bool decommitted : 1;
|
| - void initCookie()
|
| - {
|
| - m_cookie = ((reinterpret_cast<uintptr_t>(this) >> kSpanThisShift) & kSpanCookieMask) ^ spanInitializerCookie();
|
| - }
|
| - void clearCookie() { m_cookie = 0; }
|
| - bool isValid() const
|
| - {
|
| - return (((reinterpret_cast<uintptr_t>(this) >> kSpanThisShift) & kSpanCookieMask) ^ m_cookie) == spanValidationCookie;
|
| - }
|
| -private:
|
| - uint32_t m_cookie : kSpanCookieBits;
|
| -
|
| -#undef SPAN_HISTORY
|
| -#ifdef SPAN_HISTORY
|
| - // For debugging, we can keep a log events per span
|
| - int nexthistory;
|
| - char history[64];
|
| - int value[64];
|
| -#endif
|
| -};
|
| -
|
| -#define ASSERT_SPAN_COMMITTED(span) ASSERT(!span->decommitted)
|
| -
|
| -#ifdef SPAN_HISTORY
|
| -void Event(Span* span, char op, int v = 0) {
|
| - span->history[span->nexthistory] = op;
|
| - span->value[span->nexthistory] = v;
|
| - span->nexthistory++;
|
| - if (span->nexthistory == sizeof(span->history)) span->nexthistory = 0;
|
| -}
|
| -#else
|
| -#define Event(s,o,v) ((void) 0)
|
| -#endif
|
| -
|
| -// Allocator/deallocator for spans
|
| -static PageHeapAllocator<Span> span_allocator;
|
| -static Span* NewSpan(PageID p, Length len) {
|
| - Span* result = span_allocator.New();
|
| - memset(result, 0, sizeof(*result));
|
| - result->start = p;
|
| - result->length = len;
|
| - result->initCookie();
|
| -#ifdef SPAN_HISTORY
|
| - result->nexthistory = 0;
|
| -#endif
|
| - return result;
|
| -}
|
| -
|
| -static inline void DeleteSpan(Span* span) {
|
| - RELEASE_ASSERT(span->isValid());
|
| -#ifndef NDEBUG
|
| - // In debug mode, trash the contents of deleted Spans
|
| - memset(span, 0x3f, sizeof(*span));
|
| -#endif
|
| - span->clearCookie();
|
| - span_allocator.Delete(span);
|
| -}
|
| -
|
| -// -------------------------------------------------------------------------
|
| -// Doubly linked list of spans.
|
| -// -------------------------------------------------------------------------
|
| -
|
| -static inline void DLL_Init(Span* list, uintptr_t entropy) {
|
| - list->setNext(list, entropy);
|
| - list->setPrev(list, entropy);
|
| -}
|
| -
|
| -static inline void DLL_Remove(Span* span, uintptr_t entropy) {
|
| - span->prev(entropy)->setNext(span->next(entropy), entropy);
|
| - span->next(entropy)->setPrev(span->prev(entropy), entropy);
|
| - span->setPrev(NULL, entropy);
|
| - span->setNext(NULL, entropy);
|
| -}
|
| -
|
| -static ALWAYS_INLINE bool DLL_IsEmpty(const Span* list, uintptr_t entropy) {
|
| - return list->next(entropy) == list;
|
| -}
|
| -
|
| -static int DLL_Length(const Span* list, uintptr_t entropy) {
|
| - int result = 0;
|
| - for (Span* s = list->next(entropy); s != list; s = s->next(entropy)) {
|
| - result++;
|
| - }
|
| - return result;
|
| -}
|
| -
|
| -#if 0 /* Not needed at the moment -- causes compiler warnings if not used */
|
| -static void DLL_Print(const char* label, const Span* list) {
|
| - MESSAGE("%-10s %p:", label, list);
|
| - for (const Span* s = list->next; s != list; s = s->next) {
|
| - MESSAGE(" <%p,%u,%u>", s, s->start, s->length);
|
| - }
|
| - MESSAGE("\n");
|
| -}
|
| -#endif
|
| -
|
| -static inline void DLL_Prepend(Span* list, Span* span, uintptr_t entropy) {
|
| - span->setNext(list->next(entropy), entropy);
|
| - span->setPrev(list, entropy);
|
| - list->next(entropy)->setPrev(span, entropy);
|
| - list->setNext(span, entropy);
|
| -}
|
| -
|
| -//-------------------------------------------------------------------
|
| -// Data kept per size-class in central cache
|
| -//-------------------------------------------------------------------
|
| -
|
| -class TCMalloc_Central_FreeList {
|
| - public:
|
| - void Init(size_t cl, uintptr_t entropy);
|
| -
|
| - // These methods all do internal locking.
|
| -
|
| - // Insert the specified range into the central freelist. N is the number of
|
| - // elements in the range.
|
| - void InsertRange(HardenedSLL start, HardenedSLL end, int N);
|
| -
|
| - // Returns the actual number of fetched elements into N.
|
| - void RemoveRange(HardenedSLL* start, HardenedSLL* end, int *N);
|
| -
|
| - // Returns the number of free objects in cache.
|
| - size_t length() {
|
| - SpinLockHolder h(&lock_);
|
| - return counter_;
|
| - }
|
| -
|
| - // Returns the number of free objects in the transfer cache.
|
| - int tc_length() {
|
| - SpinLockHolder h(&lock_);
|
| - return used_slots_ * num_objects_to_move[size_class_];
|
| - }
|
| -
|
| -#ifdef WTF_CHANGES
|
| - template <class Finder, class Reader>
|
| - void enumerateFreeObjects(Finder& finder, const Reader& reader, TCMalloc_Central_FreeList* remoteCentralFreeList)
|
| - {
|
| - {
|
| - static const ptrdiff_t emptyOffset = reinterpret_cast<const char*>(&empty_) - reinterpret_cast<const char*>(this);
|
| - Span* remoteEmpty = reinterpret_cast<Span*>(reinterpret_cast<char*>(remoteCentralFreeList) + emptyOffset);
|
| - Span* remoteSpan = nonempty_.remoteNext(remoteEmpty, entropy_);
|
| - for (Span* span = reader(remoteEmpty); span && span != &empty_; remoteSpan = span->remoteNext(remoteSpan, entropy_), span = (remoteSpan ? reader(remoteSpan) : 0))
|
| - ASSERT(!span->objects);
|
| - }
|
| -
|
| - ASSERT(!nonempty_.objects);
|
| - static const ptrdiff_t nonemptyOffset = reinterpret_cast<const char*>(&nonempty_) - reinterpret_cast<const char*>(this);
|
| -
|
| - Span* remoteNonempty = reinterpret_cast<Span*>(reinterpret_cast<char*>(remoteCentralFreeList) + nonemptyOffset);
|
| - Span* remoteSpan = nonempty_.remoteNext(remoteNonempty, entropy_);
|
| -
|
| - for (Span* span = reader(remoteSpan); span && remoteSpan != remoteNonempty; remoteSpan = span->remoteNext(remoteSpan, entropy_), span = (remoteSpan ? reader(remoteSpan) : 0)) {
|
| - for (HardenedSLL nextObject = span->objects; nextObject; nextObject.setValue(reader.nextEntryInHardenedLinkedList(reinterpret_cast<void**>(nextObject.value()), entropy_))) {
|
| - finder.visit(nextObject.value());
|
| - }
|
| - }
|
| - }
|
| -#endif
|
| -
|
| - uintptr_t entropy() const { return entropy_; }
|
| - private:
|
| - // REQUIRES: lock_ is held
|
| - // Remove object from cache and return.
|
| - // Return NULL if no free entries in cache.
|
| - HardenedSLL FetchFromSpans();
|
| -
|
| - // REQUIRES: lock_ is held
|
| - // Remove object from cache and return. Fetches
|
| - // from pageheap if cache is empty. Only returns
|
| - // NULL on allocation failure.
|
| - HardenedSLL FetchFromSpansSafe();
|
| -
|
| - // REQUIRES: lock_ is held
|
| - // Release a linked list of objects to spans.
|
| - // May temporarily release lock_.
|
| - void ReleaseListToSpans(HardenedSLL start);
|
| -
|
| - // REQUIRES: lock_ is held
|
| - // Release an object to spans.
|
| - // May temporarily release lock_.
|
| - ALWAYS_INLINE void ReleaseToSpans(HardenedSLL object);
|
| -
|
| - // REQUIRES: lock_ is held
|
| - // Populate cache by fetching from the page heap.
|
| - // May temporarily release lock_.
|
| - ALWAYS_INLINE void Populate();
|
| -
|
| - // REQUIRES: lock is held.
|
| - // Tries to make room for a TCEntry. If the cache is full it will try to
|
| - // expand it at the cost of some other cache size. Return false if there is
|
| - // no space.
|
| - bool MakeCacheSpace();
|
| -
|
| - // REQUIRES: lock_ for locked_size_class is held.
|
| - // Picks a "random" size class to steal TCEntry slot from. In reality it
|
| - // just iterates over the sizeclasses but does so without taking a lock.
|
| - // Returns true on success.
|
| - // May temporarily lock a "random" size class.
|
| - static ALWAYS_INLINE bool EvictRandomSizeClass(size_t locked_size_class, bool force);
|
| -
|
| - // REQUIRES: lock_ is *not* held.
|
| - // Tries to shrink the Cache. If force is true it will relase objects to
|
| - // spans if it allows it to shrink the cache. Return false if it failed to
|
| - // shrink the cache. Decrements cache_size_ on succeess.
|
| - // May temporarily take lock_. If it takes lock_, the locked_size_class
|
| - // lock is released to the thread from holding two size class locks
|
| - // concurrently which could lead to a deadlock.
|
| - bool ShrinkCache(int locked_size_class, bool force);
|
| -
|
| - // This lock protects all the data members. cached_entries and cache_size_
|
| - // may be looked at without holding the lock.
|
| - SpinLock lock_;
|
| -
|
| - // We keep linked lists of empty and non-empty spans.
|
| - size_t size_class_; // My size class
|
| - Span empty_; // Dummy header for list of empty spans
|
| - Span nonempty_; // Dummy header for list of non-empty spans
|
| - size_t counter_; // Number of free objects in cache entry
|
| -
|
| - // Here we reserve space for TCEntry cache slots. Since one size class can
|
| - // end up getting all the TCEntries quota in the system we just preallocate
|
| - // sufficient number of entries here.
|
| - TCEntry tc_slots_[kNumTransferEntries];
|
| -
|
| - // Number of currently used cached entries in tc_slots_. This variable is
|
| - // updated under a lock but can be read without one.
|
| - int32_t used_slots_;
|
| - // The current number of slots for this size class. This is an
|
| - // adaptive value that is increased if there is lots of traffic
|
| - // on a given size class.
|
| - int32_t cache_size_;
|
| - uintptr_t entropy_;
|
| -};
|
| -
|
| -#if COMPILER(CLANG) && defined(__has_warning)
|
| -#pragma clang diagnostic push
|
| -#if __has_warning("-Wunused-private-field")
|
| -#pragma clang diagnostic ignored "-Wunused-private-field"
|
| -#endif
|
| -#endif
|
| -
|
| -// Pad each CentralCache object to multiple of 64 bytes
|
| -template <size_t SizeToPad>
|
| -class TCMalloc_Central_FreeListPadded_Template : public TCMalloc_Central_FreeList {
|
| -private:
|
| - char pad[64 - SizeToPad];
|
| -};
|
| -
|
| -// Zero-size specialization to avoid compiler error when TCMalloc_Central_FreeList happens
|
| -// to be exactly 64 bytes.
|
| -template <> class TCMalloc_Central_FreeListPadded_Template<0> : public TCMalloc_Central_FreeList {
|
| -};
|
| -
|
| -typedef TCMalloc_Central_FreeListPadded_Template<sizeof(TCMalloc_Central_FreeList) % 64> TCMalloc_Central_FreeListPadded;
|
| -
|
| -#if COMPILER(CLANG) && defined(__has_warning)
|
| -#pragma clang diagnostic pop
|
| -#endif
|
| -
|
| -#if OS(DARWIN)
|
| -struct Span;
|
| -class TCMalloc_PageHeap;
|
| -class TCMalloc_ThreadCache;
|
| -template <typename T> class PageHeapAllocator;
|
| -
|
| -class FastMallocZone {
|
| -public:
|
| - static void init();
|
| -
|
| - static kern_return_t enumerate(task_t, void*, unsigned typeMmask, vm_address_t zoneAddress, memory_reader_t, vm_range_recorder_t);
|
| - static size_t goodSize(malloc_zone_t*, size_t size) { return size; }
|
| - static boolean_t check(malloc_zone_t*) { return true; }
|
| - static void print(malloc_zone_t*, boolean_t) { }
|
| - static void log(malloc_zone_t*, void*) { }
|
| - static void forceLock(malloc_zone_t*) { }
|
| - static void forceUnlock(malloc_zone_t*) { }
|
| - static void statistics(malloc_zone_t*, malloc_statistics_t* stats) { memset(stats, 0, sizeof(malloc_statistics_t)); }
|
| -
|
| -private:
|
| - FastMallocZone(TCMalloc_PageHeap*, TCMalloc_ThreadCache**, TCMalloc_Central_FreeListPadded*, PageHeapAllocator<Span>*, PageHeapAllocator<TCMalloc_ThreadCache>*);
|
| - static size_t size(malloc_zone_t*, const void*);
|
| - static void* zoneMalloc(malloc_zone_t*, size_t);
|
| - static void* zoneCalloc(malloc_zone_t*, size_t numItems, size_t size);
|
| - static void zoneFree(malloc_zone_t*, void*);
|
| - static void* zoneRealloc(malloc_zone_t*, void*, size_t);
|
| - static void* zoneValloc(malloc_zone_t*, size_t) { LOG_ERROR("valloc is not supported"); return 0; }
|
| - static void zoneDestroy(malloc_zone_t*) { }
|
| -
|
| - malloc_zone_t m_zone;
|
| - TCMalloc_PageHeap* m_pageHeap;
|
| - TCMalloc_ThreadCache** m_threadHeaps;
|
| - TCMalloc_Central_FreeListPadded* m_centralCaches;
|
| - PageHeapAllocator<Span>* m_spanAllocator;
|
| - PageHeapAllocator<TCMalloc_ThreadCache>* m_pageHeapAllocator;
|
| -};
|
| -
|
| -#endif
|
| -
|
| -#endif
|
| -
|
| -#ifndef WTF_CHANGES
|
| -// This #ifdef should almost never be set. Set NO_TCMALLOC_SAMPLES if
|
| -// you're porting to a system where you really can't get a stacktrace.
|
| -#ifdef NO_TCMALLOC_SAMPLES
|
| -// We use #define so code compiles even if you #include stacktrace.h somehow.
|
| -# define GetStackTrace(stack, depth, skip) (0)
|
| -#else
|
| -# include <google/stacktrace.h>
|
| -#endif
|
| -#endif
|
| -
|
| -// Even if we have support for thread-local storage in the compiler
|
| -// and linker, the OS may not support it. We need to check that at
|
| -// runtime. Right now, we have to keep a manual set of "bad" OSes.
|
| -#if defined(HAVE_TLS)
|
| - static bool kernel_supports_tls = false; // be conservative
|
| - static inline bool KernelSupportsTLS() {
|
| - return kernel_supports_tls;
|
| - }
|
| -# if !HAVE_DECL_UNAME // if too old for uname, probably too old for TLS
|
| - static void CheckIfKernelSupportsTLS() {
|
| - kernel_supports_tls = false;
|
| - }
|
| -# else
|
| -# include <sys/utsname.h> // DECL_UNAME checked for <sys/utsname.h> too
|
| - static void CheckIfKernelSupportsTLS() {
|
| - struct utsname buf;
|
| - if (uname(&buf) != 0) { // should be impossible
|
| - MESSAGE("uname failed assuming no TLS support (errno=%d)\n", errno);
|
| - kernel_supports_tls = false;
|
| - } else if (strcasecmp(buf.sysname, "linux") == 0) {
|
| - // The linux case: the first kernel to support TLS was 2.6.0
|
| - if (buf.release[0] < '2' && buf.release[1] == '.') // 0.x or 1.x
|
| - kernel_supports_tls = false;
|
| - else if (buf.release[0] == '2' && buf.release[1] == '.' &&
|
| - buf.release[2] >= '0' && buf.release[2] < '6' &&
|
| - buf.release[3] == '.') // 2.0 - 2.5
|
| - kernel_supports_tls = false;
|
| - else
|
| - kernel_supports_tls = true;
|
| - } else { // some other kernel, we'll be optimisitic
|
| - kernel_supports_tls = true;
|
| - }
|
| - // TODO(csilvers): VLOG(1) the tls status once we support RAW_VLOG
|
| - }
|
| -# endif // HAVE_DECL_UNAME
|
| -#endif // HAVE_TLS
|
| -
|
| -// __THROW is defined in glibc systems. It means, counter-intuitively,
|
| -// "This function will never throw an exception." It's an optional
|
| -// optimization tool, but we may need to use it to match glibc prototypes.
|
| -#ifndef __THROW // I guess we're not on a glibc system
|
| -# define __THROW // __THROW is just an optimization, so ok to make it ""
|
| -#endif
|
| -
|
| -// -------------------------------------------------------------------------
|
| -// Stack traces kept for sampled allocations
|
| -// The following state is protected by pageheap_lock_.
|
| -// -------------------------------------------------------------------------
|
| -
|
| -// size/depth are made the same size as a pointer so that some generic
|
| -// code below can conveniently cast them back and forth to void*.
|
| -static const int kMaxStackDepth = 31;
|
| -struct StackTrace {
|
| - uintptr_t size; // Size of object
|
| - uintptr_t depth; // Number of PC values stored in array below
|
| - void* stack[kMaxStackDepth];
|
| -};
|
| -static PageHeapAllocator<StackTrace> stacktrace_allocator;
|
| -static Span sampled_objects;
|
| -
|
| -// -------------------------------------------------------------------------
|
| -// Map from page-id to per-page data
|
| -// -------------------------------------------------------------------------
|
| -
|
| -// We use PageMap2<> for 32-bit and PageMap3<> for 64-bit machines.
|
| -// We also use a simple one-level cache for hot PageID-to-sizeclass mappings,
|
| -// because sometimes the sizeclass is all the information we need.
|
| -
|
| -// Selector class -- general selector uses 3-level map
|
| -template <int BITS> class MapSelector {
|
| - public:
|
| - typedef TCMalloc_PageMap3<BITS-kPageShift> Type;
|
| - typedef PackedCache<BITS, uint64_t> CacheType;
|
| -};
|
| -
|
| -#if defined(WTF_CHANGES)
|
| -#if CPU(X86_64)
|
| -// On all known X86-64 platforms, the upper 16 bits are always unused and therefore
|
| -// can be excluded from the PageMap key.
|
| -// See http://en.wikipedia.org/wiki/X86-64#Virtual_address_space_details
|
| -
|
| -static const size_t kBitsUnusedOn64Bit = 16;
|
| -#else
|
| -static const size_t kBitsUnusedOn64Bit = 0;
|
| -#endif
|
| -
|
| -// A three-level map for 64-bit machines
|
| -template <> class MapSelector<64> {
|
| - public:
|
| - typedef TCMalloc_PageMap3<64 - kPageShift - kBitsUnusedOn64Bit> Type;
|
| - typedef PackedCache<64, uint64_t> CacheType;
|
| -};
|
| -#endif
|
| -
|
| -// A two-level map for 32-bit machines
|
| -template <> class MapSelector<32> {
|
| - public:
|
| - typedef TCMalloc_PageMap2<32 - kPageShift> Type;
|
| - typedef PackedCache<32 - kPageShift, uint16_t> CacheType;
|
| -};
|
| -
|
| -// -------------------------------------------------------------------------
|
| -// Page-level allocator
|
| -// * Eager coalescing
|
| -//
|
| -// Heap for page-level allocation. We allow allocating and freeing a
|
| -// contiguous runs of pages (called a "span").
|
| -// -------------------------------------------------------------------------
|
| -
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| -// The page heap maintains a free list for spans that are no longer in use by
|
| -// the central cache or any thread caches. We use a background thread to
|
| -// periodically scan the free list and release a percentage of it back to the OS.
|
| -
|
| -// If free_committed_pages_ exceeds kMinimumFreeCommittedPageCount, the
|
| -// background thread:
|
| -// - wakes up
|
| -// - pauses for kScavengeDelayInSeconds
|
| -// - returns to the OS a percentage of the memory that remained unused during
|
| -// that pause (kScavengePercentage * min_free_committed_pages_since_last_scavenge_)
|
| -// The goal of this strategy is to reduce memory pressure in a timely fashion
|
| -// while avoiding thrashing the OS allocator.
|
| -
|
| -// Time delay before the page heap scavenger will consider returning pages to
|
| -// the OS.
|
| -static const int kScavengeDelayInSeconds = 2;
|
| -
|
| -// Approximate percentage of free committed pages to return to the OS in one
|
| -// scavenge.
|
| -static const float kScavengePercentage = .5f;
|
| -
|
| -// number of span lists to keep spans in when memory is returned.
|
| -static const int kMinSpanListsWithSpans = 32;
|
| -
|
| -// Number of free committed pages that we want to keep around. The minimum number of pages used when there
|
| -// is 1 span in each of the first kMinSpanListsWithSpans spanlists. Currently 528 pages.
|
| -static const size_t kMinimumFreeCommittedPageCount = kMinSpanListsWithSpans * ((1.0f+kMinSpanListsWithSpans) / 2.0f);
|
| -
|
| -#endif
|
| -
|
| -static SpinLock pageheap_lock = SPINLOCK_INITIALIZER;
|
| -
|
| -class TCMalloc_PageHeap {
|
| - public:
|
| - void init();
|
| -
|
| - // Allocate a run of "n" pages. Returns zero if out of memory.
|
| - Span* New(Length n);
|
| -
|
| - // Delete the span "[p, p+n-1]".
|
| - // REQUIRES: span was returned by earlier call to New() and
|
| - // has not yet been deleted.
|
| - void Delete(Span* span);
|
| -
|
| - // Mark an allocated span as being used for small objects of the
|
| - // specified size-class.
|
| - // REQUIRES: span was returned by an earlier call to New()
|
| - // and has not yet been deleted.
|
| - void RegisterSizeClass(Span* span, size_t sc);
|
| -
|
| - // Split an allocated span into two spans: one of length "n" pages
|
| - // followed by another span of length "span->length - n" pages.
|
| - // Modifies "*span" to point to the first span of length "n" pages.
|
| - // Returns a pointer to the second span.
|
| - //
|
| - // REQUIRES: "0 < n < span->length"
|
| - // REQUIRES: !span->free
|
| - // REQUIRES: span->sizeclass == 0
|
| - Span* Split(Span* span, Length n);
|
| -
|
| - // Return the descriptor for the specified page.
|
| - inline Span* GetDescriptor(PageID p) const {
|
| - return reinterpret_cast<Span*>(pagemap_.get(p));
|
| - }
|
| -
|
| -#ifdef WTF_CHANGES
|
| - inline Span* GetDescriptorEnsureSafe(PageID p)
|
| - {
|
| - pagemap_.Ensure(p, 1);
|
| - return GetDescriptor(p);
|
| - }
|
| -
|
| - size_t ReturnedBytes() const;
|
| -#endif
|
| -
|
| - // Dump state to stderr
|
| -#ifndef WTF_CHANGES
|
| - void Dump(TCMalloc_Printer* out);
|
| -#endif
|
| -
|
| - // Return number of bytes allocated from system
|
| - inline uint64_t SystemBytes() const { return system_bytes_; }
|
| -
|
| - // Return number of free bytes in heap
|
| - uint64_t FreeBytes() const {
|
| - return (static_cast<uint64_t>(free_pages_) << kPageShift);
|
| - }
|
| -
|
| - bool Check();
|
| - size_t CheckList(Span* list, Length min_pages, Length max_pages, bool decommitted);
|
| -
|
| - // Release all pages on the free list for reuse by the OS:
|
| - void ReleaseFreePages();
|
| - void ReleaseFreeList(Span*, Span*);
|
| -
|
| - // Return 0 if we have no information, or else the correct sizeclass for p.
|
| - // Reads and writes to pagemap_cache_ do not require locking.
|
| - // The entries are 64 bits on 64-bit hardware and 16 bits on
|
| - // 32-bit hardware, and we don't mind raciness as long as each read of
|
| - // an entry yields a valid entry, not a partially updated entry.
|
| - size_t GetSizeClassIfCached(PageID p) const {
|
| - return pagemap_cache_.GetOrDefault(p, 0);
|
| - }
|
| - void CacheSizeClass(PageID p, size_t cl) const { pagemap_cache_.Put(p, cl); }
|
| -
|
| - private:
|
| - // Pick the appropriate map and cache types based on pointer size
|
| - typedef MapSelector<8*sizeof(uintptr_t)>::Type PageMap;
|
| - typedef MapSelector<8*sizeof(uintptr_t)>::CacheType PageMapCache;
|
| - PageMap pagemap_;
|
| - mutable PageMapCache pagemap_cache_;
|
| -
|
| - // We segregate spans of a given size into two circular linked
|
| - // lists: one for normal spans, and one for spans whose memory
|
| - // has been returned to the system.
|
| - struct SpanList {
|
| - Span normal;
|
| - Span returned;
|
| - };
|
| -
|
| - // List of free spans of length >= kMaxPages
|
| - SpanList large_;
|
| -
|
| - // Array mapping from span length to a doubly linked list of free spans
|
| - SpanList free_[kMaxPages];
|
| -
|
| - // Number of pages kept in free lists
|
| - uintptr_t free_pages_;
|
| -
|
| - // Used for hardening
|
| - uintptr_t entropy_;
|
| -
|
| - // Bytes allocated from system
|
| - uint64_t system_bytes_;
|
| -
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - // Number of pages kept in free lists that are still committed.
|
| - Length free_committed_pages_;
|
| -
|
| - // Minimum number of free committed pages since last scavenge. (Can be 0 if
|
| - // we've committed new pages since the last scavenge.)
|
| - Length min_free_committed_pages_since_last_scavenge_;
|
| -#endif
|
| -
|
| - bool GrowHeap(Length n);
|
| -
|
| - // REQUIRES span->length >= n
|
| - // Remove span from its free list, and move any leftover part of
|
| - // span into appropriate free lists. Also update "span" to have
|
| - // length exactly "n" and mark it as non-free so it can be returned
|
| - // to the client.
|
| - //
|
| - // "released" is true iff "span" was found on a "returned" list.
|
| - void Carve(Span* span, Length n, bool released);
|
| -
|
| - void RecordSpan(Span* span) {
|
| - pagemap_.set(span->start, span);
|
| - if (span->length > 1) {
|
| - pagemap_.set(span->start + span->length - 1, span);
|
| - }
|
| - }
|
| -
|
| - // Allocate a large span of length == n. If successful, returns a
|
| - // span of exactly the specified length. Else, returns NULL.
|
| - Span* AllocLarge(Length n);
|
| -
|
| -#if !USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - // Incrementally release some memory to the system.
|
| - // IncrementalScavenge(n) is called whenever n pages are freed.
|
| - void IncrementalScavenge(Length n);
|
| -#endif
|
| -
|
| - // Number of pages to deallocate before doing more scavenging
|
| - int64_t scavenge_counter_;
|
| -
|
| - // Index of last free list we scavenged
|
| - size_t scavenge_index_;
|
| -
|
| -#if defined(WTF_CHANGES) && OS(DARWIN)
|
| - friend class FastMallocZone;
|
| -#endif
|
| -
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - void initializeScavenger();
|
| - ALWAYS_INLINE void signalScavenger();
|
| - void scavenge();
|
| - ALWAYS_INLINE bool shouldScavenge() const;
|
| -
|
| -#if HAVE(DISPATCH_H) || OS(WINDOWS)
|
| - void periodicScavenge();
|
| - ALWAYS_INLINE bool isScavengerSuspended();
|
| - ALWAYS_INLINE void scheduleScavenger();
|
| - ALWAYS_INLINE void rescheduleScavenger();
|
| - ALWAYS_INLINE void suspendScavenger();
|
| -#endif
|
| -
|
| -#if HAVE(DISPATCH_H)
|
| - dispatch_queue_t m_scavengeQueue;
|
| - dispatch_source_t m_scavengeTimer;
|
| - bool m_scavengingSuspended;
|
| -#elif OS(WINDOWS)
|
| - static void CALLBACK scavengerTimerFired(void*, BOOLEAN);
|
| - HANDLE m_scavengeQueueTimer;
|
| -#else
|
| - static NO_RETURN_WITH_VALUE void* runScavengerThread(void*);
|
| - NO_RETURN void scavengerThread();
|
| -
|
| - // Keeps track of whether the background thread is actively scavenging memory every kScavengeDelayInSeconds, or
|
| - // it's blocked waiting for more pages to be deleted.
|
| - bool m_scavengeThreadActive;
|
| -
|
| - pthread_mutex_t m_scavengeMutex;
|
| - pthread_cond_t m_scavengeCondition;
|
| -#endif
|
| -
|
| -#endif // USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| -};
|
| -
|
| -void TCMalloc_PageHeap::init()
|
| -{
|
| - pagemap_.init(MetaDataAlloc);
|
| - pagemap_cache_ = PageMapCache(0);
|
| - free_pages_ = 0;
|
| - system_bytes_ = 0;
|
| - entropy_ = HARDENING_ENTROPY;
|
| -
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - free_committed_pages_ = 0;
|
| - min_free_committed_pages_since_last_scavenge_ = 0;
|
| -#endif // USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| -
|
| - scavenge_counter_ = 0;
|
| - // Start scavenging at kMaxPages list
|
| - scavenge_index_ = kMaxPages-1;
|
| - COMPILE_ASSERT(kNumClasses <= (1 << PageMapCache::kValuebits), valuebits);
|
| - DLL_Init(&large_.normal, entropy_);
|
| - DLL_Init(&large_.returned, entropy_);
|
| - for (size_t i = 0; i < kMaxPages; i++) {
|
| - DLL_Init(&free_[i].normal, entropy_);
|
| - DLL_Init(&free_[i].returned, entropy_);
|
| - }
|
| -
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - initializeScavenger();
|
| -#endif // USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| -}
|
| -
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| -
|
| -#if HAVE(DISPATCH_H)
|
| -
|
| -void TCMalloc_PageHeap::initializeScavenger()
|
| -{
|
| - m_scavengeQueue = dispatch_queue_create("com.apple.JavaScriptCore.FastMallocSavenger", NULL);
|
| - m_scavengeTimer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, m_scavengeQueue);
|
| - uint64_t scavengeDelayInNanoseconds = kScavengeDelayInSeconds * NSEC_PER_SEC;
|
| - dispatch_time_t startTime = dispatch_time(DISPATCH_TIME_NOW, scavengeDelayInNanoseconds);
|
| - dispatch_source_set_timer(m_scavengeTimer, startTime, scavengeDelayInNanoseconds, scavengeDelayInNanoseconds / 10);
|
| - dispatch_source_set_event_handler(m_scavengeTimer, ^{ periodicScavenge(); });
|
| - m_scavengingSuspended = true;
|
| -}
|
| -
|
| -ALWAYS_INLINE bool TCMalloc_PageHeap::isScavengerSuspended()
|
| -{
|
| - ASSERT(pageheap_lock.IsHeld());
|
| - return m_scavengingSuspended;
|
| -}
|
| -
|
| -ALWAYS_INLINE void TCMalloc_PageHeap::scheduleScavenger()
|
| -{
|
| - ASSERT(pageheap_lock.IsHeld());
|
| - m_scavengingSuspended = false;
|
| - dispatch_resume(m_scavengeTimer);
|
| -}
|
| -
|
| -ALWAYS_INLINE void TCMalloc_PageHeap::rescheduleScavenger()
|
| -{
|
| - // Nothing to do here for libdispatch.
|
| -}
|
| -
|
| -ALWAYS_INLINE void TCMalloc_PageHeap::suspendScavenger()
|
| -{
|
| - ASSERT(pageheap_lock.IsHeld());
|
| - m_scavengingSuspended = true;
|
| - dispatch_suspend(m_scavengeTimer);
|
| -}
|
| -
|
| -#elif OS(WINDOWS)
|
| -
|
| -void TCMalloc_PageHeap::scavengerTimerFired(void* context, BOOLEAN)
|
| -{
|
| - static_cast<TCMalloc_PageHeap*>(context)->periodicScavenge();
|
| -}
|
| -
|
| -void TCMalloc_PageHeap::initializeScavenger()
|
| -{
|
| - m_scavengeQueueTimer = 0;
|
| -}
|
| -
|
| -ALWAYS_INLINE bool TCMalloc_PageHeap::isScavengerSuspended()
|
| -{
|
| - ASSERT(pageheap_lock.IsHeld());
|
| - return !m_scavengeQueueTimer;
|
| -}
|
| -
|
| -ALWAYS_INLINE void TCMalloc_PageHeap::scheduleScavenger()
|
| -{
|
| - // We need to use WT_EXECUTEONLYONCE here and reschedule the timer, because
|
| - // Windows will fire the timer event even when the function is already running.
|
| - ASSERT(pageheap_lock.IsHeld());
|
| - CreateTimerQueueTimer(&m_scavengeQueueTimer, 0, scavengerTimerFired, this, kScavengeDelayInSeconds * 1000, 0, WT_EXECUTEONLYONCE);
|
| -}
|
| -
|
| -ALWAYS_INLINE void TCMalloc_PageHeap::rescheduleScavenger()
|
| -{
|
| - // We must delete the timer and create it again, because it is not possible to retrigger a timer on Windows.
|
| - suspendScavenger();
|
| - scheduleScavenger();
|
| -}
|
| -
|
| -ALWAYS_INLINE void TCMalloc_PageHeap::suspendScavenger()
|
| -{
|
| - ASSERT(pageheap_lock.IsHeld());
|
| - HANDLE scavengeQueueTimer = m_scavengeQueueTimer;
|
| - m_scavengeQueueTimer = 0;
|
| - DeleteTimerQueueTimer(0, scavengeQueueTimer, 0);
|
| -}
|
| -
|
| -#else
|
| -
|
| -void TCMalloc_PageHeap::initializeScavenger()
|
| -{
|
| - // Create a non-recursive mutex.
|
| -#if !defined(PTHREAD_MUTEX_NORMAL) || PTHREAD_MUTEX_NORMAL == PTHREAD_MUTEX_DEFAULT
|
| - pthread_mutex_init(&m_scavengeMutex, 0);
|
| -#else
|
| - pthread_mutexattr_t attr;
|
| - pthread_mutexattr_init(&attr);
|
| - pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_NORMAL);
|
| -
|
| - pthread_mutex_init(&m_scavengeMutex, &attr);
|
| -
|
| - pthread_mutexattr_destroy(&attr);
|
| -#endif
|
| -
|
| - pthread_cond_init(&m_scavengeCondition, 0);
|
| - m_scavengeThreadActive = true;
|
| - pthread_t thread;
|
| - pthread_create(&thread, 0, runScavengerThread, this);
|
| -}
|
| -
|
| -void* TCMalloc_PageHeap::runScavengerThread(void* context)
|
| -{
|
| - static_cast<TCMalloc_PageHeap*>(context)->scavengerThread();
|
| -#if (COMPILER(MSVC) || COMPILER(SUNCC))
|
| - // Without this, Visual Studio and Sun Studio will complain that this method does not return a value.
|
| - return 0;
|
| -#endif
|
| -}
|
| -
|
| -ALWAYS_INLINE void TCMalloc_PageHeap::signalScavenger()
|
| -{
|
| - // shouldScavenge() should be called only when the pageheap_lock spinlock is held, additionally,
|
| - // m_scavengeThreadActive is only set to false whilst pageheap_lock is held. The caller must ensure this is
|
| - // taken prior to calling this method. If the scavenger thread is sleeping and shouldScavenge() indicates there
|
| - // is memory to free the scavenger thread is signalled to start.
|
| - ASSERT(pageheap_lock.IsHeld());
|
| - if (!m_scavengeThreadActive && shouldScavenge())
|
| - pthread_cond_signal(&m_scavengeCondition);
|
| -}
|
| -
|
| -#endif
|
| -
|
| -void TCMalloc_PageHeap::scavenge()
|
| -{
|
| - size_t pagesToRelease = min_free_committed_pages_since_last_scavenge_ * kScavengePercentage;
|
| - size_t targetPageCount = std::max<size_t>(kMinimumFreeCommittedPageCount, free_committed_pages_ - pagesToRelease);
|
| -
|
| - Length lastFreeCommittedPages = free_committed_pages_;
|
| - while (free_committed_pages_ > targetPageCount) {
|
| - ASSERT(Check());
|
| - for (int i = kMaxPages; i > 0 && free_committed_pages_ >= targetPageCount; i--) {
|
| - SpanList* slist = (static_cast<size_t>(i) == kMaxPages) ? &large_ : &free_[i];
|
| - // If the span size is bigger than kMinSpanListsWithSpans pages return all the spans in the list, else return all but 1 span.
|
| - // Return only 50% of a spanlist at a time so spans of size 1 are not the only ones left.
|
| - size_t length = DLL_Length(&slist->normal, entropy_);
|
| - size_t numSpansToReturn = (i > kMinSpanListsWithSpans) ? length : length / 2;
|
| - for (int j = 0; static_cast<size_t>(j) < numSpansToReturn && !DLL_IsEmpty(&slist->normal, entropy_) && free_committed_pages_ > targetPageCount; j++) {
|
| - Span* s = slist->normal.prev(entropy_);
|
| - DLL_Remove(s, entropy_);
|
| - ASSERT(!s->decommitted);
|
| - if (!s->decommitted) {
|
| - TCMalloc_SystemRelease(reinterpret_cast<void*>(s->start << kPageShift),
|
| - static_cast<size_t>(s->length << kPageShift));
|
| - ASSERT(free_committed_pages_ >= s->length);
|
| - free_committed_pages_ -= s->length;
|
| - s->decommitted = true;
|
| - }
|
| - DLL_Prepend(&slist->returned, s, entropy_);
|
| - }
|
| - }
|
| -
|
| - if (lastFreeCommittedPages == free_committed_pages_)
|
| - break;
|
| - lastFreeCommittedPages = free_committed_pages_;
|
| - }
|
| -
|
| - min_free_committed_pages_since_last_scavenge_ = free_committed_pages_;
|
| -}
|
| -
|
| -ALWAYS_INLINE bool TCMalloc_PageHeap::shouldScavenge() const
|
| -{
|
| - return free_committed_pages_ > kMinimumFreeCommittedPageCount;
|
| -}
|
| -
|
| -#endif // USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| -
|
| -inline Span* TCMalloc_PageHeap::New(Length n) {
|
| - ASSERT(Check());
|
| - ASSERT(n > 0);
|
| -
|
| - // Find first size >= n that has a non-empty list
|
| - for (Length s = n; s < kMaxPages; s++) {
|
| - Span* ll = NULL;
|
| - bool released = false;
|
| - if (!DLL_IsEmpty(&free_[s].normal, entropy_)) {
|
| - // Found normal span
|
| - ll = &free_[s].normal;
|
| - } else if (!DLL_IsEmpty(&free_[s].returned, entropy_)) {
|
| - // Found returned span; reallocate it
|
| - ll = &free_[s].returned;
|
| - released = true;
|
| - } else {
|
| - // Keep looking in larger classes
|
| - continue;
|
| - }
|
| -
|
| - Span* result = ll->next(entropy_);
|
| - Carve(result, n, released);
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - // The newly allocated memory is from a span that's in the normal span list (already committed). Update the
|
| - // free committed pages count.
|
| - ASSERT(free_committed_pages_ >= n);
|
| - free_committed_pages_ -= n;
|
| - if (free_committed_pages_ < min_free_committed_pages_since_last_scavenge_)
|
| - min_free_committed_pages_since_last_scavenge_ = free_committed_pages_;
|
| -#endif // USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - ASSERT(Check());
|
| - free_pages_ -= n;
|
| - return result;
|
| - }
|
| -
|
| - Span* result = AllocLarge(n);
|
| - if (result != NULL) {
|
| - ASSERT_SPAN_COMMITTED(result);
|
| - return result;
|
| - }
|
| -
|
| - // Grow the heap and try again
|
| - if (!GrowHeap(n)) {
|
| - ASSERT(Check());
|
| - return NULL;
|
| - }
|
| -
|
| - return New(n);
|
| -}
|
| -
|
| -Span* TCMalloc_PageHeap::AllocLarge(Length n) {
|
| - // find the best span (closest to n in size).
|
| - // The following loops implements address-ordered best-fit.
|
| - bool from_released = false;
|
| - Span *best = NULL;
|
| -
|
| - // Search through normal list
|
| - for (Span* span = large_.normal.next(entropy_);
|
| - span != &large_.normal;
|
| - span = span->next(entropy_)) {
|
| - if (span->length >= n) {
|
| - if ((best == NULL)
|
| - || (span->length < best->length)
|
| - || ((span->length == best->length) && (span->start < best->start))) {
|
| - best = span;
|
| - from_released = false;
|
| - }
|
| - }
|
| - }
|
| -
|
| - // Search through released list in case it has a better fit
|
| - for (Span* span = large_.returned.next(entropy_);
|
| - span != &large_.returned;
|
| - span = span->next(entropy_)) {
|
| - if (span->length >= n) {
|
| - if ((best == NULL)
|
| - || (span->length < best->length)
|
| - || ((span->length == best->length) && (span->start < best->start))) {
|
| - best = span;
|
| - from_released = true;
|
| - }
|
| - }
|
| - }
|
| -
|
| - if (best != NULL) {
|
| - Carve(best, n, from_released);
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - // The newly allocated memory is from a span that's in the normal span list (already committed). Update the
|
| - // free committed pages count.
|
| - ASSERT(free_committed_pages_ >= n);
|
| - free_committed_pages_ -= n;
|
| - if (free_committed_pages_ < min_free_committed_pages_since_last_scavenge_)
|
| - min_free_committed_pages_since_last_scavenge_ = free_committed_pages_;
|
| -#endif // USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - ASSERT(Check());
|
| - free_pages_ -= n;
|
| - return best;
|
| - }
|
| - return NULL;
|
| -}
|
| -
|
| -Span* TCMalloc_PageHeap::Split(Span* span, Length n) {
|
| - ASSERT(0 < n);
|
| - ASSERT(n < span->length);
|
| - ASSERT(!span->free);
|
| - ASSERT(span->sizeclass == 0);
|
| - Event(span, 'T', n);
|
| -
|
| - const Length extra = span->length - n;
|
| - Span* leftover = NewSpan(span->start + n, extra);
|
| - Event(leftover, 'U', extra);
|
| - RecordSpan(leftover);
|
| - pagemap_.set(span->start + n - 1, span); // Update map from pageid to span
|
| - span->length = n;
|
| -
|
| - return leftover;
|
| -}
|
| -
|
| -inline void TCMalloc_PageHeap::Carve(Span* span, Length n, bool released) {
|
| - ASSERT(n > 0);
|
| - DLL_Remove(span, entropy_);
|
| - span->free = 0;
|
| - Event(span, 'A', n);
|
| -
|
| - if (released) {
|
| - // If the span chosen to carve from is decommited, commit the entire span at once to avoid committing spans 1 page at a time.
|
| - ASSERT(span->decommitted);
|
| - TCMalloc_SystemCommit(reinterpret_cast<void*>(span->start << kPageShift), static_cast<size_t>(span->length << kPageShift));
|
| - span->decommitted = false;
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - free_committed_pages_ += span->length;
|
| -#endif
|
| - }
|
| -
|
| - const int extra = static_cast<int>(span->length - n);
|
| - ASSERT(extra >= 0);
|
| - if (extra > 0) {
|
| - Span* leftover = NewSpan(span->start + n, extra);
|
| - leftover->free = 1;
|
| - leftover->decommitted = false;
|
| - Event(leftover, 'S', extra);
|
| - RecordSpan(leftover);
|
| -
|
| - // Place leftover span on appropriate free list
|
| - SpanList* listpair = (static_cast<size_t>(extra) < kMaxPages) ? &free_[extra] : &large_;
|
| - Span* dst = &listpair->normal;
|
| - DLL_Prepend(dst, leftover, entropy_);
|
| -
|
| - span->length = n;
|
| - pagemap_.set(span->start + n - 1, span);
|
| - }
|
| -}
|
| -
|
| -static ALWAYS_INLINE void mergeDecommittedStates(Span* destination, Span* other)
|
| -{
|
| - if (destination->decommitted && !other->decommitted) {
|
| - TCMalloc_SystemRelease(reinterpret_cast<void*>(other->start << kPageShift),
|
| - static_cast<size_t>(other->length << kPageShift));
|
| - } else if (other->decommitted && !destination->decommitted) {
|
| - TCMalloc_SystemRelease(reinterpret_cast<void*>(destination->start << kPageShift),
|
| - static_cast<size_t>(destination->length << kPageShift));
|
| - destination->decommitted = true;
|
| - }
|
| -}
|
| -
|
| -inline void TCMalloc_PageHeap::Delete(Span* span) {
|
| - ASSERT(Check());
|
| - ASSERT(!span->free);
|
| - ASSERT(span->length > 0);
|
| - ASSERT(GetDescriptor(span->start) == span);
|
| - ASSERT(GetDescriptor(span->start + span->length - 1) == span);
|
| - span->sizeclass = 0;
|
| -#ifndef NO_TCMALLOC_SAMPLES
|
| - span->sample = 0;
|
| -#endif
|
| -
|
| - // Coalesce -- we guarantee that "p" != 0, so no bounds checking
|
| - // necessary. We do not bother resetting the stale pagemap
|
| - // entries for the pieces we are merging together because we only
|
| - // care about the pagemap entries for the boundaries.
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - // Track the total size of the neighboring free spans that are committed.
|
| - Length neighboringCommittedSpansLength = 0;
|
| -#endif
|
| - const PageID p = span->start;
|
| - const Length n = span->length;
|
| - Span* prev = GetDescriptor(p-1);
|
| - if (prev != NULL && prev->free) {
|
| - // Merge preceding span into this span
|
| - ASSERT(prev->start + prev->length == p);
|
| - const Length len = prev->length;
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - if (!prev->decommitted)
|
| - neighboringCommittedSpansLength += len;
|
| -#endif
|
| - mergeDecommittedStates(span, prev);
|
| - DLL_Remove(prev, entropy_);
|
| - DeleteSpan(prev);
|
| - span->start -= len;
|
| - span->length += len;
|
| - pagemap_.set(span->start, span);
|
| - Event(span, 'L', len);
|
| - }
|
| - Span* next = GetDescriptor(p+n);
|
| - if (next != NULL && next->free) {
|
| - // Merge next span into this span
|
| - ASSERT(next->start == p+n);
|
| - const Length len = next->length;
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - if (!next->decommitted)
|
| - neighboringCommittedSpansLength += len;
|
| -#endif
|
| - mergeDecommittedStates(span, next);
|
| - DLL_Remove(next, entropy_);
|
| - DeleteSpan(next);
|
| - span->length += len;
|
| - pagemap_.set(span->start + span->length - 1, span);
|
| - Event(span, 'R', len);
|
| - }
|
| -
|
| - Event(span, 'D', span->length);
|
| - span->free = 1;
|
| - if (span->decommitted) {
|
| - if (span->length < kMaxPages)
|
| - DLL_Prepend(&free_[span->length].returned, span, entropy_);
|
| - else
|
| - DLL_Prepend(&large_.returned, span, entropy_);
|
| - } else {
|
| - if (span->length < kMaxPages)
|
| - DLL_Prepend(&free_[span->length].normal, span, entropy_);
|
| - else
|
| - DLL_Prepend(&large_.normal, span, entropy_);
|
| - }
|
| - free_pages_ += n;
|
| -
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - if (span->decommitted) {
|
| - // If the merged span is decommitted, that means we decommitted any neighboring spans that were
|
| - // committed. Update the free committed pages count.
|
| - free_committed_pages_ -= neighboringCommittedSpansLength;
|
| - if (free_committed_pages_ < min_free_committed_pages_since_last_scavenge_)
|
| - min_free_committed_pages_since_last_scavenge_ = free_committed_pages_;
|
| - } else {
|
| - // If the merged span remains committed, add the deleted span's size to the free committed pages count.
|
| - free_committed_pages_ += n;
|
| - }
|
| -
|
| - // Make sure the scavenge thread becomes active if we have enough freed pages to release some back to the system.
|
| - signalScavenger();
|
| -#else
|
| - IncrementalScavenge(n);
|
| -#endif
|
| -
|
| - ASSERT(Check());
|
| -}
|
| -
|
| -#if !USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| -void TCMalloc_PageHeap::IncrementalScavenge(Length n) {
|
| - // Fast path; not yet time to release memory
|
| - scavenge_counter_ -= n;
|
| - if (scavenge_counter_ >= 0) return; // Not yet time to scavenge
|
| -
|
| - // If there is nothing to release, wait for so many pages before
|
| - // scavenging again. With 4K pages, this comes to 16MB of memory.
|
| - static const size_t kDefaultReleaseDelay = 1 << 8;
|
| -
|
| - // Find index of free list to scavenge
|
| - size_t index = scavenge_index_ + 1;
|
| - uintptr_t entropy = entropy_;
|
| - for (size_t i = 0; i < kMaxPages+1; i++) {
|
| - if (index > kMaxPages) index = 0;
|
| - SpanList* slist = (index == kMaxPages) ? &large_ : &free_[index];
|
| - if (!DLL_IsEmpty(&slist->normal, entropy)) {
|
| - // Release the last span on the normal portion of this list
|
| - Span* s = slist->normal.prev(entropy);
|
| - DLL_Remove(s, entropy_);
|
| - TCMalloc_SystemRelease(reinterpret_cast<void*>(s->start << kPageShift),
|
| - static_cast<size_t>(s->length << kPageShift));
|
| - s->decommitted = true;
|
| - DLL_Prepend(&slist->returned, s, entropy);
|
| -
|
| - scavenge_counter_ = std::max<size_t>(64UL, std::min<size_t>(kDefaultReleaseDelay, kDefaultReleaseDelay - (free_pages_ / kDefaultReleaseDelay)));
|
| -
|
| - if (index == kMaxPages && !DLL_IsEmpty(&slist->normal, entropy))
|
| - scavenge_index_ = index - 1;
|
| - else
|
| - scavenge_index_ = index;
|
| - return;
|
| - }
|
| - index++;
|
| - }
|
| -
|
| - // Nothing to scavenge, delay for a while
|
| - scavenge_counter_ = kDefaultReleaseDelay;
|
| -}
|
| -#endif
|
| -
|
| -void TCMalloc_PageHeap::RegisterSizeClass(Span* span, size_t sc) {
|
| - // Associate span object with all interior pages as well
|
| - ASSERT(!span->free);
|
| - ASSERT(GetDescriptor(span->start) == span);
|
| - ASSERT(GetDescriptor(span->start+span->length-1) == span);
|
| - Event(span, 'C', sc);
|
| - span->sizeclass = static_cast<unsigned int>(sc);
|
| - for (Length i = 1; i < span->length-1; i++) {
|
| - pagemap_.set(span->start+i, span);
|
| - }
|
| -}
|
| -
|
| -#ifdef WTF_CHANGES
|
| -size_t TCMalloc_PageHeap::ReturnedBytes() const {
|
| - size_t result = 0;
|
| - for (unsigned s = 0; s < kMaxPages; s++) {
|
| - const int r_length = DLL_Length(&free_[s].returned, entropy_);
|
| - unsigned r_pages = s * r_length;
|
| - result += r_pages << kPageShift;
|
| - }
|
| -
|
| - for (Span* s = large_.returned.next(entropy_); s != &large_.returned; s = s->next(entropy_))
|
| - result += s->length << kPageShift;
|
| - return result;
|
| -}
|
| -#endif
|
| -
|
| -#ifndef WTF_CHANGES
|
| -static double PagesToMB(uint64_t pages) {
|
| - return (pages << kPageShift) / 1048576.0;
|
| -}
|
| -
|
| -void TCMalloc_PageHeap::Dump(TCMalloc_Printer* out) {
|
| - int nonempty_sizes = 0;
|
| - for (int s = 0; s < kMaxPages; s++) {
|
| - if (!DLL_IsEmpty(&free_[s].normal) || !DLL_IsEmpty(&free_[s].returned)) {
|
| - nonempty_sizes++;
|
| - }
|
| - }
|
| - out->printf("------------------------------------------------\n");
|
| - out->printf("PageHeap: %d sizes; %6.1f MB free\n",
|
| - nonempty_sizes, PagesToMB(free_pages_));
|
| - out->printf("------------------------------------------------\n");
|
| - uint64_t total_normal = 0;
|
| - uint64_t total_returned = 0;
|
| - for (int s = 0; s < kMaxPages; s++) {
|
| - const int n_length = DLL_Length(&free_[s].normal);
|
| - const int r_length = DLL_Length(&free_[s].returned);
|
| - if (n_length + r_length > 0) {
|
| - uint64_t n_pages = s * n_length;
|
| - uint64_t r_pages = s * r_length;
|
| - total_normal += n_pages;
|
| - total_returned += r_pages;
|
| - out->printf("%6u pages * %6u spans ~ %6.1f MB; %6.1f MB cum"
|
| - "; unmapped: %6.1f MB; %6.1f MB cum\n",
|
| - s,
|
| - (n_length + r_length),
|
| - PagesToMB(n_pages + r_pages),
|
| - PagesToMB(total_normal + total_returned),
|
| - PagesToMB(r_pages),
|
| - PagesToMB(total_returned));
|
| - }
|
| - }
|
| -
|
| - uint64_t n_pages = 0;
|
| - uint64_t r_pages = 0;
|
| - int n_spans = 0;
|
| - int r_spans = 0;
|
| - out->printf("Normal large spans:\n");
|
| - for (Span* s = large_.normal.next; s != &large_.normal; s = s->next) {
|
| - out->printf(" [ %6" PRIuS " pages ] %6.1f MB\n",
|
| - s->length, PagesToMB(s->length));
|
| - n_pages += s->length;
|
| - n_spans++;
|
| - }
|
| - out->printf("Unmapped large spans:\n");
|
| - for (Span* s = large_.returned.next; s != &large_.returned; s = s->next) {
|
| - out->printf(" [ %6" PRIuS " pages ] %6.1f MB\n",
|
| - s->length, PagesToMB(s->length));
|
| - r_pages += s->length;
|
| - r_spans++;
|
| - }
|
| - total_normal += n_pages;
|
| - total_returned += r_pages;
|
| - out->printf(">255 large * %6u spans ~ %6.1f MB; %6.1f MB cum"
|
| - "; unmapped: %6.1f MB; %6.1f MB cum\n",
|
| - (n_spans + r_spans),
|
| - PagesToMB(n_pages + r_pages),
|
| - PagesToMB(total_normal + total_returned),
|
| - PagesToMB(r_pages),
|
| - PagesToMB(total_returned));
|
| -}
|
| -#endif
|
| -
|
| -bool TCMalloc_PageHeap::GrowHeap(Length n) {
|
| - ASSERT(kMaxPages >= kMinSystemAlloc);
|
| - if (n > kMaxValidPages) return false;
|
| - Length ask = (n>kMinSystemAlloc) ? n : static_cast<Length>(kMinSystemAlloc);
|
| - size_t actual_size;
|
| - void* ptr = TCMalloc_SystemAlloc(ask << kPageShift, &actual_size, kPageSize);
|
| - if (ptr == NULL) {
|
| - if (n < ask) {
|
| - // Try growing just "n" pages
|
| - ask = n;
|
| - ptr = TCMalloc_SystemAlloc(ask << kPageShift, &actual_size, kPageSize);
|
| - }
|
| - if (ptr == NULL) return false;
|
| - }
|
| - ask = actual_size >> kPageShift;
|
| -
|
| - uint64_t old_system_bytes = system_bytes_;
|
| - system_bytes_ += (ask << kPageShift);
|
| - const PageID p = reinterpret_cast<uintptr_t>(ptr) >> kPageShift;
|
| - ASSERT(p > 0);
|
| -
|
| - // If we have already a lot of pages allocated, just pre allocate a bunch of
|
| - // memory for the page map. This prevents fragmentation by pagemap metadata
|
| - // when a program keeps allocating and freeing large blocks.
|
| -
|
| - if (old_system_bytes < kPageMapBigAllocationThreshold
|
| - && system_bytes_ >= kPageMapBigAllocationThreshold) {
|
| - pagemap_.PreallocateMoreMemory();
|
| - }
|
| -
|
| - // Make sure pagemap_ has entries for all of the new pages.
|
| - // Plus ensure one before and one after so coalescing code
|
| - // does not need bounds-checking.
|
| - if (pagemap_.Ensure(p-1, ask+2)) {
|
| - // Pretend the new area is allocated and then Delete() it to
|
| - // cause any necessary coalescing to occur.
|
| - //
|
| - // We do not adjust free_pages_ here since Delete() will do it for us.
|
| - Span* span = NewSpan(p, ask);
|
| - RecordSpan(span);
|
| - Delete(span);
|
| - ASSERT(Check());
|
| - return true;
|
| - } else {
|
| - // We could not allocate memory within "pagemap_"
|
| - // TODO: Once we can return memory to the system, return the new span
|
| - return false;
|
| - }
|
| -}
|
| -
|
| -bool TCMalloc_PageHeap::Check() {
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - size_t totalFreeCommitted = 0;
|
| -#endif
|
| - ASSERT(free_[0].normal.next(entropy_) == &free_[0].normal);
|
| - ASSERT(free_[0].returned.next(entropy_) == &free_[0].returned);
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - totalFreeCommitted = CheckList(&large_.normal, kMaxPages, 1000000000, false);
|
| -#else
|
| - CheckList(&large_.normal, kMaxPages, 1000000000, false);
|
| -#endif
|
| - CheckList(&large_.returned, kMaxPages, 1000000000, true);
|
| - for (Length s = 1; s < kMaxPages; s++) {
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - totalFreeCommitted += CheckList(&free_[s].normal, s, s, false);
|
| -#else
|
| - CheckList(&free_[s].normal, s, s, false);
|
| -#endif
|
| - CheckList(&free_[s].returned, s, s, true);
|
| - }
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - ASSERT(totalFreeCommitted == free_committed_pages_);
|
| -#endif
|
| - return true;
|
| -}
|
| -
|
| -#if ASSERT_DISABLED
|
| -size_t TCMalloc_PageHeap::CheckList(Span*, Length, Length, bool) {
|
| - return 0;
|
| -}
|
| -#else
|
| -size_t TCMalloc_PageHeap::CheckList(Span* list, Length min_pages, Length max_pages, bool decommitted) {
|
| - size_t freeCount = 0;
|
| - for (Span* s = list->next(entropy_); s != list; s = s->next(entropy_)) {
|
| - CHECK_CONDITION(s->free);
|
| - CHECK_CONDITION(s->length >= min_pages);
|
| - CHECK_CONDITION(s->length <= max_pages);
|
| - CHECK_CONDITION(GetDescriptor(s->start) == s);
|
| - CHECK_CONDITION(GetDescriptor(s->start+s->length-1) == s);
|
| - CHECK_CONDITION(s->decommitted == decommitted);
|
| - freeCount += s->length;
|
| - }
|
| - return freeCount;
|
| -}
|
| -#endif
|
| -
|
| -void TCMalloc_PageHeap::ReleaseFreeList(Span* list, Span* returned) {
|
| - // Walk backwards through list so that when we push these
|
| - // spans on the "returned" list, we preserve the order.
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - size_t freePageReduction = 0;
|
| -#endif
|
| -
|
| - while (!DLL_IsEmpty(list, entropy_)) {
|
| - Span* s = list->prev(entropy_);
|
| -
|
| - DLL_Remove(s, entropy_);
|
| - s->decommitted = true;
|
| - DLL_Prepend(returned, s, entropy_);
|
| - TCMalloc_SystemRelease(reinterpret_cast<void*>(s->start << kPageShift),
|
| - static_cast<size_t>(s->length << kPageShift));
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - freePageReduction += s->length;
|
| -#endif
|
| - }
|
| -
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| - free_committed_pages_ -= freePageReduction;
|
| - if (free_committed_pages_ < min_free_committed_pages_since_last_scavenge_)
|
| - min_free_committed_pages_since_last_scavenge_ = free_committed_pages_;
|
| -#endif
|
| -}
|
| -
|
| -void TCMalloc_PageHeap::ReleaseFreePages() {
|
| - for (Length s = 0; s < kMaxPages; s++) {
|
| - ReleaseFreeList(&free_[s].normal, &free_[s].returned);
|
| - }
|
| - ReleaseFreeList(&large_.normal, &large_.returned);
|
| - ASSERT(Check());
|
| -}
|
| -
|
| -//-------------------------------------------------------------------
|
| -// Free list
|
| -//-------------------------------------------------------------------
|
| -
|
| -class TCMalloc_ThreadCache_FreeList {
|
| - private:
|
| - HardenedSLL list_; // Linked list of nodes
|
| - uint16_t length_; // Current length
|
| - uint16_t lowater_; // Low water mark for list length
|
| - uintptr_t entropy_; // Entropy source for hardening
|
| -
|
| - public:
|
| - void Init(uintptr_t entropy) {
|
| - list_.setValue(NULL);
|
| - length_ = 0;
|
| - lowater_ = 0;
|
| - entropy_ = entropy;
|
| -#if ENABLE(TCMALLOC_HARDENING)
|
| - ASSERT(entropy_);
|
| -#endif
|
| - }
|
| -
|
| - // Return current length of list
|
| - int length() const {
|
| - return length_;
|
| - }
|
| -
|
| - // Is list empty?
|
| - bool empty() const {
|
| - return !list_;
|
| - }
|
| -
|
| - // Low-water mark management
|
| - int lowwatermark() const { return lowater_; }
|
| - void clear_lowwatermark() { lowater_ = length_; }
|
| -
|
| - ALWAYS_INLINE void Push(HardenedSLL ptr) {
|
| - SLL_Push(&list_, ptr, entropy_);
|
| - length_++;
|
| - }
|
| -
|
| - void PushRange(int N, HardenedSLL start, HardenedSLL end) {
|
| - SLL_PushRange(&list_, start, end, entropy_);
|
| - length_ = length_ + static_cast<uint16_t>(N);
|
| - }
|
| -
|
| - void PopRange(int N, HardenedSLL* start, HardenedSLL* end) {
|
| - SLL_PopRange(&list_, N, start, end, entropy_);
|
| - ASSERT(length_ >= N);
|
| - length_ = length_ - static_cast<uint16_t>(N);
|
| - if (length_ < lowater_) lowater_ = length_;
|
| - }
|
| -
|
| - ALWAYS_INLINE void* Pop() {
|
| - ASSERT(list_);
|
| - length_--;
|
| - if (length_ < lowater_) lowater_ = length_;
|
| - return SLL_Pop(&list_, entropy_).value();
|
| - }
|
| -
|
| - // Runs through the linked list to ensure that
|
| - // we can do that, and ensures that 'missing'
|
| - // is not present
|
| - NEVER_INLINE void Validate(HardenedSLL missing, size_t size) {
|
| - HardenedSLL node = list_;
|
| - UNUSED_PARAM(size);
|
| - while (node) {
|
| - RELEASE_ASSERT(node != missing);
|
| - RELEASE_ASSERT(IS_DEFINITELY_POISONED(node.value(), size));
|
| - node = SLL_Next(node, entropy_);
|
| - }
|
| - }
|
| -
|
| -#ifdef WTF_CHANGES
|
| - template <class Finder, class Reader>
|
| - void enumerateFreeObjects(Finder& finder, const Reader& reader)
|
| - {
|
| - for (HardenedSLL nextObject = list_; nextObject; nextObject.setValue(reader.nextEntryInHardenedLinkedList(reinterpret_cast<void**>(nextObject.value()), entropy_)))
|
| - finder.visit(nextObject.value());
|
| - }
|
| -#endif
|
| -};
|
| -
|
| -//-------------------------------------------------------------------
|
| -// Data kept per thread
|
| -//-------------------------------------------------------------------
|
| -
|
| -class TCMalloc_ThreadCache {
|
| - private:
|
| - typedef TCMalloc_ThreadCache_FreeList FreeList;
|
| -#if OS(WINDOWS)
|
| - typedef DWORD ThreadIdentifier;
|
| -#else
|
| - typedef pthread_t ThreadIdentifier;
|
| -#endif
|
| -
|
| - size_t size_; // Combined size of data
|
| - ThreadIdentifier tid_; // Which thread owns it
|
| - bool in_setspecific_; // Called pthread_setspecific?
|
| - FreeList list_[kNumClasses]; // Array indexed by size-class
|
| -
|
| - // We sample allocations, biased by the size of the allocation
|
| - uint32_t rnd_; // Cheap random number generator
|
| - size_t bytes_until_sample_; // Bytes until we sample next
|
| -
|
| - uintptr_t entropy_; // Entropy value used for hardening
|
| -
|
| - // Allocate a new heap. REQUIRES: pageheap_lock is held.
|
| - static inline TCMalloc_ThreadCache* NewHeap(ThreadIdentifier tid, uintptr_t entropy);
|
| -
|
| - // Use only as pthread thread-specific destructor function.
|
| - static void DestroyThreadCache(void* ptr);
|
| - public:
|
| - // All ThreadCache objects are kept in a linked list (for stats collection)
|
| - TCMalloc_ThreadCache* next_;
|
| - TCMalloc_ThreadCache* prev_;
|
| -
|
| - void Init(ThreadIdentifier tid, uintptr_t entropy);
|
| - void Cleanup();
|
| -
|
| - // Accessors (mostly just for printing stats)
|
| - int freelist_length(size_t cl) const { return list_[cl].length(); }
|
| -
|
| - // Total byte size in cache
|
| - size_t Size() const { return size_; }
|
| -
|
| - ALWAYS_INLINE void* Allocate(size_t size);
|
| - void Deallocate(HardenedSLL ptr, size_t size_class);
|
| -
|
| - ALWAYS_INLINE void FetchFromCentralCache(size_t cl, size_t allocationSize);
|
| - void ReleaseToCentralCache(size_t cl, int N);
|
| - void Scavenge();
|
| - void Print() const;
|
| -
|
| - // Record allocation of "k" bytes. Return true iff allocation
|
| - // should be sampled
|
| - bool SampleAllocation(size_t k);
|
| -
|
| - // Pick next sampling point
|
| - void PickNextSample(size_t k);
|
| -
|
| - static void InitModule();
|
| - static void InitTSD();
|
| - static TCMalloc_ThreadCache* GetThreadHeap();
|
| - static TCMalloc_ThreadCache* GetCache();
|
| - static TCMalloc_ThreadCache* GetCacheIfPresent();
|
| - static TCMalloc_ThreadCache* CreateCacheIfNecessary();
|
| - static void DeleteCache(TCMalloc_ThreadCache* heap);
|
| - static void BecomeIdle();
|
| - static void RecomputeThreadCacheSize();
|
| -
|
| -#ifdef WTF_CHANGES
|
| - template <class Finder, class Reader>
|
| - void enumerateFreeObjects(Finder& finder, const Reader& reader)
|
| - {
|
| - for (unsigned sizeClass = 0; sizeClass < kNumClasses; sizeClass++)
|
| - list_[sizeClass].enumerateFreeObjects(finder, reader);
|
| - }
|
| -#endif
|
| -};
|
| -
|
| -//-------------------------------------------------------------------
|
| -// Global variables
|
| -//-------------------------------------------------------------------
|
| -
|
| -// Central cache -- a collection of free-lists, one per size-class.
|
| -// We have a separate lock per free-list to reduce contention.
|
| -static TCMalloc_Central_FreeListPadded central_cache[kNumClasses];
|
| -
|
| -// Page-level allocator
|
| -static AllocAlignmentInteger pageheap_memory[(sizeof(TCMalloc_PageHeap) + sizeof(AllocAlignmentInteger) - 1) / sizeof(AllocAlignmentInteger)];
|
| -static bool phinited = false;
|
| -
|
| -// Avoid extra level of indirection by making "pageheap" be just an alias
|
| -// of pageheap_memory.
|
| -typedef union {
|
| - void* m_memory;
|
| - TCMalloc_PageHeap* m_pageHeap;
|
| -} PageHeapUnion;
|
| -
|
| -static inline TCMalloc_PageHeap* getPageHeap()
|
| -{
|
| - PageHeapUnion u = { &pageheap_memory[0] };
|
| - return u.m_pageHeap;
|
| -}
|
| -
|
| -#define pageheap getPageHeap()
|
| -
|
| -size_t fastMallocGoodSize(size_t bytes)
|
| -{
|
| - if (!phinited)
|
| - TCMalloc_ThreadCache::InitModule();
|
| - return AllocationSize(bytes);
|
| -}
|
| -
|
| -#if USE_BACKGROUND_THREAD_TO_SCAVENGE_MEMORY
|
| -
|
| -#if HAVE(DISPATCH_H) || OS(WINDOWS)
|
| -
|
| -void TCMalloc_PageHeap::periodicScavenge()
|
| -{
|
| - SpinLockHolder h(&pageheap_lock);
|
| - pageheap->scavenge();
|
| -
|
| - if (shouldScavenge()) {
|
| - rescheduleScavenger();
|
| - return;
|
| - }
|
| -
|
| - suspendScavenger();
|
| -}
|
| -
|
| -ALWAYS_INLINE void TCMalloc_PageHeap::signalScavenger()
|
| -{
|
| - ASSERT(pageheap_lock.IsHeld());
|
| - if (isScavengerSuspended() && shouldScavenge())
|
| - scheduleScavenger();
|
| -}
|
| -
|
| -#else
|
| -
|
| -void TCMalloc_PageHeap::scavengerThread()
|
| -{
|
| -#if HAVE(PTHREAD_SETNAME_NP)
|
| - pthread_setname_np("JavaScriptCore: FastMalloc scavenger");
|
| -#endif
|
| -
|
| - while (1) {
|
| - pageheap_lock.Lock();
|
| - if (!shouldScavenge()) {
|
| - // Set to false so that signalScavenger() will check whether we need to be siganlled.
|
| - m_scavengeThreadActive = false;
|
| -
|
| - // We need to unlock now, as this thread will block on the condvar until scavenging is required.
|
| - pageheap_lock.Unlock();
|
| -
|
| - // Block until there are enough free committed pages to release back to the system.
|
| - pthread_mutex_lock(&m_scavengeMutex);
|
| - pthread_cond_wait(&m_scavengeCondition, &m_scavengeMutex);
|
| - // After exiting the pthread_cond_wait, we hold the lock on m_scavengeMutex. Unlock it to prevent
|
| - // deadlock next time round the loop.
|
| - pthread_mutex_unlock(&m_scavengeMutex);
|
| -
|
| - // Set to true to prevent unnecessary signalling of the condvar.
|
| - m_scavengeThreadActive = true;
|
| - } else
|
| - pageheap_lock.Unlock();
|
| -
|
| - // Wait for a while to calculate how much memory remains unused during this pause.
|
| - sleep(kScavengeDelayInSeconds);
|
| -
|
| - {
|
| - SpinLockHolder h(&pageheap_lock);
|
| - pageheap->scavenge();
|
| - }
|
| - }
|
| -}
|
| -
|
| -#endif
|
| -
|
| -#endif
|
| -
|
| -// If TLS is available, we also store a copy
|
| -// of the per-thread object in a __thread variable
|
| -// since __thread variables are faster to read
|
| -// than pthread_getspecific(). We still need
|
| -// pthread_setspecific() because __thread
|
| -// variables provide no way to run cleanup
|
| -// code when a thread is destroyed.
|
| -#ifdef HAVE_TLS
|
| -static __thread TCMalloc_ThreadCache *threadlocal_heap;
|
| -#endif
|
| -// Thread-specific key. Initialization here is somewhat tricky
|
| -// because some Linux startup code invokes malloc() before it
|
| -// is in a good enough state to handle pthread_keycreate().
|
| -// Therefore, we use TSD keys only after tsd_inited is set to true.
|
| -// Until then, we use a slow path to get the heap object.
|
| -static bool tsd_inited = false;
|
| -#if USE(PTHREAD_GETSPECIFIC_DIRECT)
|
| -static const pthread_key_t heap_key = __PTK_FRAMEWORK_JAVASCRIPTCORE_KEY0;
|
| -#else
|
| -static pthread_key_t heap_key;
|
| -#endif
|
| -#if OS(WINDOWS)
|
| -DWORD tlsIndex = TLS_OUT_OF_INDEXES;
|
| -#endif
|
| -
|
| -static ALWAYS_INLINE void setThreadHeap(TCMalloc_ThreadCache* heap)
|
| -{
|
| -#if USE(PTHREAD_GETSPECIFIC_DIRECT)
|
| - // Can't have two libraries both doing this in the same process,
|
| - // so check and make this crash right away.
|
| - if (pthread_getspecific(heap_key))
|
| - CRASH();
|
| -#endif
|
| -
|
| - // Still do pthread_setspecific even if there's an alternate form
|
| - // of thread-local storage in use, to benefit from the delete callback.
|
| - pthread_setspecific(heap_key, heap);
|
| -
|
| -#if OS(WINDOWS)
|
| - TlsSetValue(tlsIndex, heap);
|
| -#endif
|
| -}
|
| -
|
| -// Allocator for thread heaps
|
| -static PageHeapAllocator<TCMalloc_ThreadCache> threadheap_allocator;
|
| -
|
| -// Linked list of heap objects. Protected by pageheap_lock.
|
| -static TCMalloc_ThreadCache* thread_heaps = NULL;
|
| -static int thread_heap_count = 0;
|
| -
|
| -// Overall thread cache size. Protected by pageheap_lock.
|
| -static size_t overall_thread_cache_size = kDefaultOverallThreadCacheSize;
|
| -
|
| -// Global per-thread cache size. Writes are protected by
|
| -// pageheap_lock. Reads are done without any locking, which should be
|
| -// fine as long as size_t can be written atomically and we don't place
|
| -// invariants between this variable and other pieces of state.
|
| -static volatile size_t per_thread_cache_size = kMaxThreadCacheSize;
|
| -
|
| -//-------------------------------------------------------------------
|
| -// Central cache implementation
|
| -//-------------------------------------------------------------------
|
| -
|
| -void TCMalloc_Central_FreeList::Init(size_t cl, uintptr_t entropy) {
|
| - lock_.Init();
|
| - size_class_ = cl;
|
| - entropy_ = entropy;
|
| -#if ENABLE(TCMALLOC_HARDENING)
|
| - ASSERT(entropy_);
|
| -#endif
|
| - DLL_Init(&empty_, entropy_);
|
| - DLL_Init(&nonempty_, entropy_);
|
| - counter_ = 0;
|
| -
|
| - cache_size_ = 1;
|
| - used_slots_ = 0;
|
| - ASSERT(cache_size_ <= kNumTransferEntries);
|
| -}
|
| -
|
| -void TCMalloc_Central_FreeList::ReleaseListToSpans(HardenedSLL start) {
|
| - while (start) {
|
| - HardenedSLL next = SLL_Next(start, entropy_);
|
| - ReleaseToSpans(start);
|
| - start = next;
|
| - }
|
| -}
|
| -
|
| -ALWAYS_INLINE void TCMalloc_Central_FreeList::ReleaseToSpans(HardenedSLL object) {
|
| - const PageID p = reinterpret_cast<uintptr_t>(object.value()) >> kPageShift;
|
| - Span* span = pageheap->GetDescriptor(p);
|
| - ASSERT(span != NULL);
|
| - ASSERT(span->refcount > 0);
|
| -
|
| - // If span is empty, move it to non-empty list
|
| - if (!span->objects) {
|
| - DLL_Remove(span, entropy_);
|
| - DLL_Prepend(&nonempty_, span, entropy_);
|
| - Event(span, 'N', 0);
|
| - }
|
| -
|
| - // The following check is expensive, so it is disabled by default
|
| - if (false) {
|
| - // Check that object does not occur in list
|
| - unsigned got = 0;
|
| - for (HardenedSLL p = span->objects; !p; SLL_Next(p, entropy_)) {
|
| - ASSERT(p.value() != object.value());
|
| - got++;
|
| - }
|
| - ASSERT(got + span->refcount ==
|
| - (span->length<<kPageShift)/ByteSizeForClass(span->sizeclass));
|
| - }
|
| -
|
| - counter_++;
|
| - span->refcount--;
|
| - if (span->refcount == 0) {
|
| - Event(span, '#', 0);
|
| - counter_ -= (span->length<<kPageShift) / ByteSizeForClass(span->sizeclass);
|
| - DLL_Remove(span, entropy_);
|
| -
|
| - // Release central list lock while operating on pageheap
|
| - lock_.Unlock();
|
| - {
|
| - SpinLockHolder h(&pageheap_lock);
|
| - pageheap->Delete(span);
|
| - }
|
| - lock_.Lock();
|
| - } else {
|
| - SLL_SetNext(object, span->objects, entropy_);
|
| - span->objects.setValue(object.value());
|
| - }
|
| -}
|
| -
|
| -ALWAYS_INLINE bool TCMalloc_Central_FreeList::EvictRandomSizeClass(
|
| - size_t locked_size_class, bool force) {
|
| - static int race_counter = 0;
|
| - int t = race_counter++; // Updated without a lock, but who cares.
|
| - if (t >= static_cast<int>(kNumClasses)) {
|
| - while (t >= static_cast<int>(kNumClasses)) {
|
| - t -= kNumClasses;
|
| - }
|
| - race_counter = t;
|
| - }
|
| - ASSERT(t >= 0);
|
| - ASSERT(t < static_cast<int>(kNumClasses));
|
| - if (t == static_cast<int>(locked_size_class)) return false;
|
| - return central_cache[t].ShrinkCache(static_cast<int>(locked_size_class), force);
|
| -}
|
| -
|
| -bool TCMalloc_Central_FreeList::MakeCacheSpace() {
|
| - // Is there room in the cache?
|
| - if (used_slots_ < cache_size_) return true;
|
| - // Check if we can expand this cache?
|
| - if (cache_size_ == kNumTransferEntries) return false;
|
| - // Ok, we'll try to grab an entry from some other size class.
|
| - if (EvictRandomSizeClass(size_class_, false) ||
|
| - EvictRandomSizeClass(size_class_, true)) {
|
| - // Succeeded in evicting, we're going to make our cache larger.
|
| - cache_size_++;
|
| - return true;
|
| - }
|
| - return false;
|
| -}
|
| -
|
| -
|
| -namespace {
|
| -class LockInverter {
|
| - private:
|
| - SpinLock *held_, *temp_;
|
| - public:
|
| - inline explicit LockInverter(SpinLock* held, SpinLock *temp)
|
| - : held_(held), temp_(temp) { held_->Unlock(); temp_->Lock(); }
|
| - inline ~LockInverter() { temp_->Unlock(); held_->Lock(); }
|
| -};
|
| -}
|
| -
|
| -bool TCMalloc_Central_FreeList::ShrinkCache(int locked_size_class, bool force) {
|
| - // Start with a quick check without taking a lock.
|
| - if (cache_size_ == 0) return false;
|
| - // We don't evict from a full cache unless we are 'forcing'.
|
| - if (force == false && used_slots_ == cache_size_) return false;
|
| -
|
| - // Grab lock, but first release the other lock held by this thread. We use
|
| - // the lock inverter to ensure that we never hold two size class locks
|
| - // concurrently. That can create a deadlock because there is no well
|
| - // defined nesting order.
|
| - LockInverter li(¢ral_cache[locked_size_class].lock_, &lock_);
|
| - ASSERT(used_slots_ <= cache_size_);
|
| - ASSERT(0 <= cache_size_);
|
| - if (cache_size_ == 0) return false;
|
| - if (used_slots_ == cache_size_) {
|
| - if (force == false) return false;
|
| - // ReleaseListToSpans releases the lock, so we have to make all the
|
| - // updates to the central list before calling it.
|
| - cache_size_--;
|
| - used_slots_--;
|
| - ReleaseListToSpans(tc_slots_[used_slots_].head);
|
| - return true;
|
| - }
|
| - cache_size_--;
|
| - return true;
|
| -}
|
| -
|
| -void TCMalloc_Central_FreeList::InsertRange(HardenedSLL start, HardenedSLL end, int N) {
|
| - SpinLockHolder h(&lock_);
|
| - if (N == num_objects_to_move[size_class_] &&
|
| - MakeCacheSpace()) {
|
| - int slot = used_slots_++;
|
| - ASSERT(slot >=0);
|
| - ASSERT(slot < kNumTransferEntries);
|
| - TCEntry *entry = &tc_slots_[slot];
|
| - entry->head = start;
|
| - entry->tail = end;
|
| - return;
|
| - }
|
| - ReleaseListToSpans(start);
|
| -}
|
| -
|
| -void TCMalloc_Central_FreeList::RemoveRange(HardenedSLL* start, HardenedSLL* end, int *N) {
|
| - int num = *N;
|
| - ASSERT(num > 0);
|
| -
|
| - SpinLockHolder h(&lock_);
|
| - if (num == num_objects_to_move[size_class_] && used_slots_ > 0) {
|
| - int slot = --used_slots_;
|
| - ASSERT(slot >= 0);
|
| - TCEntry *entry = &tc_slots_[slot];
|
| - *start = entry->head;
|
| - *end = entry->tail;
|
| - return;
|
| - }
|
| -
|
| - // TODO: Prefetch multiple TCEntries?
|
| - HardenedSLL tail = FetchFromSpansSafe();
|
| - if (!tail) {
|
| - // We are completely out of memory.
|
| - *start = *end = HardenedSLL::null();
|
| - *N = 0;
|
| - return;
|
| - }
|
| -
|
| - SLL_SetNext(tail, HardenedSLL::null(), entropy_);
|
| - HardenedSLL head = tail;
|
| - int count = 1;
|
| - while (count < num) {
|
| - HardenedSLL t = FetchFromSpans();
|
| - if (!t) break;
|
| - SLL_Push(&head, t, entropy_);
|
| - count++;
|
| - }
|
| - *start = head;
|
| - *end = tail;
|
| - *N = count;
|
| -}
|
| -
|
| -
|
| -HardenedSLL TCMalloc_Central_FreeList::FetchFromSpansSafe() {
|
| - HardenedSLL t = FetchFromSpans();
|
| - if (!t) {
|
| - Populate();
|
| - t = FetchFromSpans();
|
| - }
|
| - return t;
|
| -}
|
| -
|
| -HardenedSLL TCMalloc_Central_FreeList::FetchFromSpans() {
|
| - if (DLL_IsEmpty(&nonempty_, entropy_)) return HardenedSLL::null();
|
| - Span* span = nonempty_.next(entropy_);
|
| -
|
| - ASSERT(span->objects);
|
| - ASSERT_SPAN_COMMITTED(span);
|
| - span->refcount++;
|
| - HardenedSLL result = span->objects;
|
| - span->objects = SLL_Next(result, entropy_);
|
| - if (!span->objects) {
|
| - // Move to empty list
|
| - DLL_Remove(span, entropy_);
|
| - DLL_Prepend(&empty_, span, entropy_);
|
| - Event(span, 'E', 0);
|
| - }
|
| - counter_--;
|
| - return result;
|
| -}
|
| -
|
| -// Fetch memory from the system and add to the central cache freelist.
|
| -ALWAYS_INLINE void TCMalloc_Central_FreeList::Populate() {
|
| - // Release central list lock while operating on pageheap
|
| - lock_.Unlock();
|
| - const size_t npages = class_to_pages[size_class_];
|
| -
|
| - Span* span;
|
| - {
|
| - SpinLockHolder h(&pageheap_lock);
|
| - span = pageheap->New(npages);
|
| - if (span) pageheap->RegisterSizeClass(span, size_class_);
|
| - }
|
| - if (span == NULL) {
|
| -#if HAVE(ERRNO_H)
|
| - MESSAGE("allocation failed: %d\n", errno);
|
| -#elif OS(WINDOWS)
|
| - MESSAGE("allocation failed: %d\n", ::GetLastError());
|
| -#else
|
| - MESSAGE("allocation failed\n");
|
| -#endif
|
| - lock_.Lock();
|
| - return;
|
| - }
|
| - ASSERT_SPAN_COMMITTED(span);
|
| - ASSERT(span->length == npages);
|
| - // Cache sizeclass info eagerly. Locking is not necessary.
|
| - // (Instead of being eager, we could just replace any stale info
|
| - // about this span, but that seems to be no better in practice.)
|
| - for (size_t i = 0; i < npages; i++) {
|
| - pageheap->CacheSizeClass(span->start + i, size_class_);
|
| - }
|
| -
|
| - // Split the block into pieces and add to the free-list
|
| - // TODO: coloring of objects to avoid cache conflicts?
|
| - HardenedSLL head = HardenedSLL::null();
|
| - char* start = reinterpret_cast<char*>(span->start << kPageShift);
|
| - const size_t size = ByteSizeForClass(size_class_);
|
| - char* ptr = start + (npages << kPageShift) - ((npages << kPageShift) % size);
|
| - int num = 0;
|
| -#if ENABLE(TCMALLOC_HARDENING)
|
| - uint32_t startPoison = freedObjectStartPoison();
|
| - uint32_t endPoison = freedObjectEndPoison();
|
| -#endif
|
| -
|
| - while (ptr > start) {
|
| - ptr -= size;
|
| - HardenedSLL node = HardenedSLL::create(ptr);
|
| - POISON_DEALLOCATION_EXPLICIT(ptr, size, startPoison, endPoison);
|
| - SLL_SetNext(node, head, entropy_);
|
| - head = node;
|
| - num++;
|
| - }
|
| - ASSERT(ptr == start);
|
| - ASSERT(ptr == head.value());
|
| -#ifndef NDEBUG
|
| - {
|
| - HardenedSLL node = head;
|
| - while (node) {
|
| - ASSERT(IS_DEFINITELY_POISONED(node.value(), size));
|
| - node = SLL_Next(node, entropy_);
|
| - }
|
| - }
|
| -#endif
|
| - span->objects = head;
|
| - ASSERT(span->objects.value() == head.value());
|
| - span->refcount = 0; // No sub-object in use yet
|
| -
|
| - // Add span to list of non-empty spans
|
| - lock_.Lock();
|
| - DLL_Prepend(&nonempty_, span, entropy_);
|
| - counter_ += num;
|
| -}
|
| -
|
| -//-------------------------------------------------------------------
|
| -// TCMalloc_ThreadCache implementation
|
| -//-------------------------------------------------------------------
|
| -
|
| -inline bool TCMalloc_ThreadCache::SampleAllocation(size_t k) {
|
| - if (bytes_until_sample_ < k) {
|
| - PickNextSample(k);
|
| - return true;
|
| - } else {
|
| - bytes_until_sample_ -= k;
|
| - return false;
|
| - }
|
| -}
|
| -
|
| -void TCMalloc_ThreadCache::Init(ThreadIdentifier tid, uintptr_t entropy) {
|
| - size_ = 0;
|
| - next_ = NULL;
|
| - prev_ = NULL;
|
| - tid_ = tid;
|
| - in_setspecific_ = false;
|
| - entropy_ = entropy;
|
| -#if ENABLE(TCMALLOC_HARDENING)
|
| - ASSERT(entropy_);
|
| -#endif
|
| - for (size_t cl = 0; cl < kNumClasses; ++cl) {
|
| - list_[cl].Init(entropy_);
|
| - }
|
| -
|
| - // Initialize RNG -- run it for a bit to get to good values
|
| - bytes_until_sample_ = 0;
|
| - rnd_ = static_cast<uint32_t>(reinterpret_cast<uintptr_t>(this));
|
| - for (int i = 0; i < 100; i++) {
|
| - PickNextSample(static_cast<size_t>(FLAGS_tcmalloc_sample_parameter * 2));
|
| - }
|
| -}
|
| -
|
| -void TCMalloc_ThreadCache::Cleanup() {
|
| - // Put unused memory back into central cache
|
| - for (size_t cl = 0; cl < kNumClasses; ++cl) {
|
| - if (list_[cl].length() > 0) {
|
| - ReleaseToCentralCache(cl, list_[cl].length());
|
| - }
|
| - }
|
| -}
|
| -
|
| -ALWAYS_INLINE void* TCMalloc_ThreadCache::Allocate(size_t size) {
|
| - ASSERT(size <= kMaxSize);
|
| - const size_t cl = SizeClass(size);
|
| - FreeList* list = &list_[cl];
|
| - size_t allocationSize = ByteSizeForClass(cl);
|
| - if (list->empty()) {
|
| - FetchFromCentralCache(cl, allocationSize);
|
| - if (list->empty()) return NULL;
|
| - }
|
| - size_ -= allocationSize;
|
| - void* result = list->Pop();
|
| - if (!result)
|
| - return 0;
|
| - RELEASE_ASSERT(IS_DEFINITELY_POISONED(result, allocationSize));
|
| - POISON_ALLOCATION(result, allocationSize);
|
| - return result;
|
| -}
|
| -
|
| -inline void TCMalloc_ThreadCache::Deallocate(HardenedSLL ptr, size_t cl) {
|
| - size_t allocationSize = ByteSizeForClass(cl);
|
| - size_ += allocationSize;
|
| - FreeList* list = &list_[cl];
|
| - if (MAY_BE_POISONED(ptr.value(), allocationSize))
|
| - list->Validate(ptr, allocationSize);
|
| -
|
| - POISON_DEALLOCATION(ptr.value(), allocationSize);
|
| - list->Push(ptr);
|
| - // If enough data is free, put back into central cache
|
| - if (list->length() > kMaxFreeListLength) {
|
| - ReleaseToCentralCache(cl, num_objects_to_move[cl]);
|
| - }
|
| - if (size_ >= per_thread_cache_size) Scavenge();
|
| -}
|
| -
|
| -// Remove some objects of class "cl" from central cache and add to thread heap
|
| -ALWAYS_INLINE void TCMalloc_ThreadCache::FetchFromCentralCache(size_t cl, size_t allocationSize) {
|
| - int fetch_count = num_objects_to_move[cl];
|
| - HardenedSLL start, end;
|
| - central_cache[cl].RemoveRange(&start, &end, &fetch_count);
|
| - list_[cl].PushRange(fetch_count, start, end);
|
| - size_ += allocationSize * fetch_count;
|
| -}
|
| -
|
| -// Remove some objects of class "cl" from thread heap and add to central cache
|
| -inline void TCMalloc_ThreadCache::ReleaseToCentralCache(size_t cl, int N) {
|
| - ASSERT(N > 0);
|
| - FreeList* src = &list_[cl];
|
| - if (N > src->length()) N = src->length();
|
| - size_ -= N*ByteSizeForClass(cl);
|
| -
|
| - // We return prepackaged chains of the correct size to the central cache.
|
| - // TODO: Use the same format internally in the thread caches?
|
| - int batch_size = num_objects_to_move[cl];
|
| - while (N > batch_size) {
|
| - HardenedSLL tail, head;
|
| - src->PopRange(batch_size, &head, &tail);
|
| - central_cache[cl].InsertRange(head, tail, batch_size);
|
| - N -= batch_size;
|
| - }
|
| - HardenedSLL tail, head;
|
| - src->PopRange(N, &head, &tail);
|
| - central_cache[cl].InsertRange(head, tail, N);
|
| -}
|
| -
|
| -// Release idle memory to the central cache
|
| -inline void TCMalloc_ThreadCache::Scavenge() {
|
| - // If the low-water mark for the free list is L, it means we would
|
| - // not have had to allocate anything from the central cache even if
|
| - // we had reduced the free list size by L. We aim to get closer to
|
| - // that situation by dropping L/2 nodes from the free list. This
|
| - // may not release much memory, but if so we will call scavenge again
|
| - // pretty soon and the low-water marks will be high on that call.
|
| - //int64 start = CycleClock::Now();
|
| -
|
| - for (size_t cl = 0; cl < kNumClasses; cl++) {
|
| - FreeList* list = &list_[cl];
|
| - const int lowmark = list->lowwatermark();
|
| - if (lowmark > 0) {
|
| - const int drop = (lowmark > 1) ? lowmark/2 : 1;
|
| - ReleaseToCentralCache(cl, drop);
|
| - }
|
| - list->clear_lowwatermark();
|
| - }
|
| -
|
| - //int64 finish = CycleClock::Now();
|
| - //CycleTimer ct;
|
| - //MESSAGE("GC: %.0f ns\n", ct.CyclesToUsec(finish-start)*1000.0);
|
| -}
|
| -
|
| -void TCMalloc_ThreadCache::PickNextSample(size_t k) {
|
| - // Make next "random" number
|
| - // x^32+x^22+x^2+x^1+1 is a primitive polynomial for random numbers
|
| - static const uint32_t kPoly = (1 << 22) | (1 << 2) | (1 << 1) | (1 << 0);
|
| - uint32_t r = rnd_;
|
| - rnd_ = (r << 1) ^ ((static_cast<int32_t>(r) >> 31) & kPoly);
|
| -
|
| - // Next point is "rnd_ % (sample_period)". I.e., average
|
| - // increment is "sample_period/2".
|
| - const int flag_value = static_cast<int>(FLAGS_tcmalloc_sample_parameter);
|
| - static int last_flag_value = -1;
|
| -
|
| - if (flag_value != last_flag_value) {
|
| - SpinLockHolder h(&sample_period_lock);
|
| - int i;
|
| - for (i = 0; i < (static_cast<int>(sizeof(primes_list)/sizeof(primes_list[0])) - 1); i++) {
|
| - if (primes_list[i] >= flag_value) {
|
| - break;
|
| - }
|
| - }
|
| - sample_period = primes_list[i];
|
| - last_flag_value = flag_value;
|
| - }
|
| -
|
| - bytes_until_sample_ += rnd_ % sample_period;
|
| -
|
| - if (k > (static_cast<size_t>(-1) >> 2)) {
|
| - // If the user has asked for a huge allocation then it is possible
|
| - // for the code below to loop infinitely. Just return (note that
|
| - // this throws off the sampling accuracy somewhat, but a user who
|
| - // is allocating more than 1G of memory at a time can live with a
|
| - // minor inaccuracy in profiling of small allocations, and also
|
| - // would rather not wait for the loop below to terminate).
|
| - return;
|
| - }
|
| -
|
| - while (bytes_until_sample_ < k) {
|
| - // Increase bytes_until_sample_ by enough average sampling periods
|
| - // (sample_period >> 1) to allow us to sample past the current
|
| - // allocation.
|
| - bytes_until_sample_ += (sample_period >> 1);
|
| - }
|
| -
|
| - bytes_until_sample_ -= k;
|
| -}
|
| -
|
| -void TCMalloc_ThreadCache::InitModule() {
|
| - // There is a slight potential race here because of double-checked
|
| - // locking idiom. However, as long as the program does a small
|
| - // allocation before switching to multi-threaded mode, we will be
|
| - // fine. We increase the chances of doing such a small allocation
|
| - // by doing one in the constructor of the module_enter_exit_hook
|
| - // object declared below.
|
| - SpinLockHolder h(&pageheap_lock);
|
| - if (!phinited) {
|
| - uintptr_t entropy = HARDENING_ENTROPY;
|
| -#ifdef WTF_CHANGES
|
| - InitTSD();
|
| -#endif
|
| - InitSizeClasses();
|
| - threadheap_allocator.Init(entropy);
|
| - span_allocator.Init(entropy);
|
| - span_allocator.New(); // Reduce cache conflicts
|
| - span_allocator.New(); // Reduce cache conflicts
|
| - stacktrace_allocator.Init(entropy);
|
| - DLL_Init(&sampled_objects, entropy);
|
| - for (size_t i = 0; i < kNumClasses; ++i) {
|
| - central_cache[i].Init(i, entropy);
|
| - }
|
| - pageheap->init();
|
| - phinited = 1;
|
| -#if defined(WTF_CHANGES) && OS(DARWIN)
|
| - FastMallocZone::init();
|
| -#endif
|
| - }
|
| -}
|
| -
|
| -inline TCMalloc_ThreadCache* TCMalloc_ThreadCache::NewHeap(ThreadIdentifier tid, uintptr_t entropy) {
|
| - // Create the heap and add it to the linked list
|
| - TCMalloc_ThreadCache *heap = threadheap_allocator.New();
|
| - heap->Init(tid, entropy);
|
| - heap->next_ = thread_heaps;
|
| - heap->prev_ = NULL;
|
| - if (thread_heaps != NULL) thread_heaps->prev_ = heap;
|
| - thread_heaps = heap;
|
| - thread_heap_count++;
|
| - RecomputeThreadCacheSize();
|
| - return heap;
|
| -}
|
| -
|
| -inline TCMalloc_ThreadCache* TCMalloc_ThreadCache::GetThreadHeap() {
|
| -#ifdef HAVE_TLS
|
| - // __thread is faster, but only when the kernel supports it
|
| - if (KernelSupportsTLS())
|
| - return threadlocal_heap;
|
| -#elif OS(WINDOWS)
|
| - return static_cast<TCMalloc_ThreadCache*>(TlsGetValue(tlsIndex));
|
| -#else
|
| - return static_cast<TCMalloc_ThreadCache*>(pthread_getspecific(heap_key));
|
| -#endif
|
| -}
|
| -
|
| -inline TCMalloc_ThreadCache* TCMalloc_ThreadCache::GetCache() {
|
| - TCMalloc_ThreadCache* ptr = NULL;
|
| - if (!tsd_inited) {
|
| - InitModule();
|
| - } else {
|
| - ptr = GetThreadHeap();
|
| - }
|
| - if (ptr == NULL) ptr = CreateCacheIfNecessary();
|
| - return ptr;
|
| -}
|
| -
|
| -// In deletion paths, we do not try to create a thread-cache. This is
|
| -// because we may be in the thread destruction code and may have
|
| -// already cleaned up the cache for this thread.
|
| -inline TCMalloc_ThreadCache* TCMalloc_ThreadCache::GetCacheIfPresent() {
|
| - if (!tsd_inited) return NULL;
|
| - void* const p = GetThreadHeap();
|
| - return reinterpret_cast<TCMalloc_ThreadCache*>(p);
|
| -}
|
| -
|
| -void TCMalloc_ThreadCache::InitTSD() {
|
| - ASSERT(!tsd_inited);
|
| -#if USE(PTHREAD_GETSPECIFIC_DIRECT)
|
| - pthread_key_init_np(heap_key, DestroyThreadCache);
|
| -#else
|
| - pthread_key_create(&heap_key, DestroyThreadCache);
|
| -#endif
|
| -#if OS(WINDOWS)
|
| - tlsIndex = TlsAlloc();
|
| -#endif
|
| - tsd_inited = true;
|
| -
|
| -#if !OS(WINDOWS)
|
| - // We may have used a fake pthread_t for the main thread. Fix it.
|
| - pthread_t zero;
|
| - memset(&zero, 0, sizeof(zero));
|
| -#endif
|
| -#ifndef WTF_CHANGES
|
| - SpinLockHolder h(&pageheap_lock);
|
| -#else
|
| - ASSERT(pageheap_lock.IsHeld());
|
| -#endif
|
| - for (TCMalloc_ThreadCache* h = thread_heaps; h != NULL; h = h->next_) {
|
| -#if OS(WINDOWS)
|
| - if (h->tid_ == 0) {
|
| - h->tid_ = GetCurrentThreadId();
|
| - }
|
| -#else
|
| - if (pthread_equal(h->tid_, zero)) {
|
| - h->tid_ = pthread_self();
|
| - }
|
| -#endif
|
| - }
|
| -}
|
| -
|
| -TCMalloc_ThreadCache* TCMalloc_ThreadCache::CreateCacheIfNecessary() {
|
| - // Initialize per-thread data if necessary
|
| - TCMalloc_ThreadCache* heap = NULL;
|
| - {
|
| - SpinLockHolder h(&pageheap_lock);
|
| -
|
| -#if OS(WINDOWS)
|
| - DWORD me;
|
| - if (!tsd_inited) {
|
| - me = 0;
|
| - } else {
|
| - me = GetCurrentThreadId();
|
| - }
|
| -#else
|
| - // Early on in glibc's life, we cannot even call pthread_self()
|
| - pthread_t me;
|
| - if (!tsd_inited) {
|
| - memset(&me, 0, sizeof(me));
|
| - } else {
|
| - me = pthread_self();
|
| - }
|
| -#endif
|
| -
|
| - // This may be a recursive malloc call from pthread_setspecific()
|
| - // In that case, the heap for this thread has already been created
|
| - // and added to the linked list. So we search for that first.
|
| - for (TCMalloc_ThreadCache* h = thread_heaps; h != NULL; h = h->next_) {
|
| -#if OS(WINDOWS)
|
| - if (h->tid_ == me) {
|
| -#else
|
| - if (pthread_equal(h->tid_, me)) {
|
| -#endif
|
| - heap = h;
|
| - break;
|
| - }
|
| - }
|
| -
|
| - if (heap == NULL) heap = NewHeap(me, HARDENING_ENTROPY);
|
| - }
|
| -
|
| - // We call pthread_setspecific() outside the lock because it may
|
| - // call malloc() recursively. The recursive call will never get
|
| - // here again because it will find the already allocated heap in the
|
| - // linked list of heaps.
|
| - if (!heap->in_setspecific_ && tsd_inited) {
|
| - heap->in_setspecific_ = true;
|
| - setThreadHeap(heap);
|
| - }
|
| - return heap;
|
| -}
|
| -
|
| -void TCMalloc_ThreadCache::BecomeIdle() {
|
| - if (!tsd_inited) return; // No caches yet
|
| - TCMalloc_ThreadCache* heap = GetThreadHeap();
|
| - if (heap == NULL) return; // No thread cache to remove
|
| - if (heap->in_setspecific_) return; // Do not disturb the active caller
|
| -
|
| - heap->in_setspecific_ = true;
|
| - setThreadHeap(NULL);
|
| -#ifdef HAVE_TLS
|
| - // Also update the copy in __thread
|
| - threadlocal_heap = NULL;
|
| -#endif
|
| - heap->in_setspecific_ = false;
|
| - if (GetThreadHeap() == heap) {
|
| - // Somehow heap got reinstated by a recursive call to malloc
|
| - // from pthread_setspecific. We give up in this case.
|
| - return;
|
| - }
|
| -
|
| - // We can now get rid of the heap
|
| - DeleteCache(heap);
|
| -}
|
| -
|
| -void TCMalloc_ThreadCache::DestroyThreadCache(void* ptr) {
|
| - // Note that "ptr" cannot be NULL since pthread promises not
|
| - // to invoke the destructor on NULL values, but for safety,
|
| - // we check anyway.
|
| - if (ptr == NULL) return;
|
| -#ifdef HAVE_TLS
|
| - // Prevent fast path of GetThreadHeap() from returning heap.
|
| - threadlocal_heap = NULL;
|
| -#endif
|
| - DeleteCache(reinterpret_cast<TCMalloc_ThreadCache*>(ptr));
|
| -}
|
| -
|
| -void TCMalloc_ThreadCache::DeleteCache(TCMalloc_ThreadCache* heap) {
|
| - // Remove all memory from heap
|
| - heap->Cleanup();
|
| -
|
| - // Remove from linked list
|
| - SpinLockHolder h(&pageheap_lock);
|
| - if (heap->next_ != NULL) heap->next_->prev_ = heap->prev_;
|
| - if (heap->prev_ != NULL) heap->prev_->next_ = heap->next_;
|
| - if (thread_heaps == heap) thread_heaps = heap->next_;
|
| - thread_heap_count--;
|
| - RecomputeThreadCacheSize();
|
| -
|
| - threadheap_allocator.Delete(heap);
|
| -}
|
| -
|
| -void TCMalloc_ThreadCache::RecomputeThreadCacheSize() {
|
| - // Divide available space across threads
|
| - int n = thread_heap_count > 0 ? thread_heap_count : 1;
|
| - size_t space = overall_thread_cache_size / n;
|
| -
|
| - // Limit to allowed range
|
| - if (space < kMinThreadCacheSize) space = kMinThreadCacheSize;
|
| - if (space > kMaxThreadCacheSize) space = kMaxThreadCacheSize;
|
| -
|
| - per_thread_cache_size = space;
|
| -}
|
| -
|
| -void TCMalloc_ThreadCache::Print() const {
|
| - for (size_t cl = 0; cl < kNumClasses; ++cl) {
|
| - MESSAGE(" %5" PRIuS " : %4d len; %4d lo\n",
|
| - ByteSizeForClass(cl),
|
| - list_[cl].length(),
|
| - list_[cl].lowwatermark());
|
| - }
|
| -}
|
| -
|
| -// Extract interesting stats
|
| -struct TCMallocStats {
|
| - uint64_t system_bytes; // Bytes alloced from system
|
| - uint64_t thread_bytes; // Bytes in thread caches
|
| - uint64_t central_bytes; // Bytes in central cache
|
| - uint64_t transfer_bytes; // Bytes in central transfer cache
|
| - uint64_t pageheap_bytes; // Bytes in page heap
|
| - uint64_t metadata_bytes; // Bytes alloced for metadata
|
| -};
|
| -
|
| -#ifndef WTF_CHANGES
|
| -// Get stats into "r". Also get per-size-class counts if class_count != NULL
|
| -static void ExtractStats(TCMallocStats* r, uint64_t* class_count) {
|
| - r->central_bytes = 0;
|
| - r->transfer_bytes = 0;
|
| - for (int cl = 0; cl < kNumClasses; ++cl) {
|
| - const int length = central_cache[cl].length();
|
| - const int tc_length = central_cache[cl].tc_length();
|
| - r->central_bytes += static_cast<uint64_t>(ByteSizeForClass(cl)) * length;
|
| - r->transfer_bytes +=
|
| - static_cast<uint64_t>(ByteSizeForClass(cl)) * tc_length;
|
| - if (class_count) class_count[cl] = length + tc_length;
|
| - }
|
| -
|
| - // Add stats from per-thread heaps
|
| - r->thread_bytes = 0;
|
| - { // scope
|
| - SpinLockHolder h(&pageheap_lock);
|
| - for (TCMalloc_ThreadCache* h = thread_heaps; h != NULL; h = h->next_) {
|
| - r->thread_bytes += h->Size();
|
| - if (class_count) {
|
| - for (size_t cl = 0; cl < kNumClasses; ++cl) {
|
| - class_count[cl] += h->freelist_length(cl);
|
| - }
|
| - }
|
| - }
|
| - }
|
| -
|
| - { //scope
|
| - SpinLockHolder h(&pageheap_lock);
|
| - r->system_bytes = pageheap->SystemBytes();
|
| - r->metadata_bytes = metadata_system_bytes;
|
| - r->pageheap_bytes = pageheap->FreeBytes();
|
| - }
|
| -}
|
| -#endif
|
| -
|
| -#ifndef WTF_CHANGES
|
| -// WRITE stats to "out"
|
| -static void DumpStats(TCMalloc_Printer* out, int level) {
|
| - TCMallocStats stats;
|
| - uint64_t class_count[kNumClasses];
|
| - ExtractStats(&stats, (level >= 2 ? class_count : NULL));
|
| -
|
| - if (level >= 2) {
|
| - out->printf("------------------------------------------------\n");
|
| - uint64_t cumulative = 0;
|
| - for (int cl = 0; cl < kNumClasses; ++cl) {
|
| - if (class_count[cl] > 0) {
|
| - uint64_t class_bytes = class_count[cl] * ByteSizeForClass(cl);
|
| - cumulative += class_bytes;
|
| - out->printf("class %3d [ %8" PRIuS " bytes ] : "
|
| - "%8" PRIu64 " objs; %5.1f MB; %5.1f cum MB\n",
|
| - cl, ByteSizeForClass(cl),
|
| - class_count[cl],
|
| - class_bytes / 1048576.0,
|
| - cumulative / 1048576.0);
|
| - }
|
| - }
|
| -
|
| - SpinLockHolder h(&pageheap_lock);
|
| - pageheap->Dump(out);
|
| - }
|
| -
|
| - const uint64_t bytes_in_use = stats.system_bytes
|
| - - stats.pageheap_bytes
|
| - - stats.central_bytes
|
| - - stats.transfer_bytes
|
| - - stats.thread_bytes;
|
| -
|
| - out->printf("------------------------------------------------\n"
|
| - "MALLOC: %12" PRIu64 " Heap size\n"
|
| - "MALLOC: %12" PRIu64 " Bytes in use by application\n"
|
| - "MALLOC: %12" PRIu64 " Bytes free in page heap\n"
|
| - "MALLOC: %12" PRIu64 " Bytes free in central cache\n"
|
| - "MALLOC: %12" PRIu64 " Bytes free in transfer cache\n"
|
| - "MALLOC: %12" PRIu64 " Bytes free in thread caches\n"
|
| - "MALLOC: %12" PRIu64 " Spans in use\n"
|
| - "MALLOC: %12" PRIu64 " Thread heaps in use\n"
|
| - "MALLOC: %12" PRIu64 " Metadata allocated\n"
|
| - "------------------------------------------------\n",
|
| - stats.system_bytes,
|
| - bytes_in_use,
|
| - stats.pageheap_bytes,
|
| - stats.central_bytes,
|
| - stats.transfer_bytes,
|
| - stats.thread_bytes,
|
| - uint64_t(span_allocator.inuse()),
|
| - uint64_t(threadheap_allocator.inuse()),
|
| - stats.metadata_bytes);
|
| -}
|
| -
|
| -static void PrintStats(int level) {
|
| - const int kBufferSize = 16 << 10;
|
| - char* buffer = new char[kBufferSize];
|
| - TCMalloc_Printer printer(buffer, kBufferSize);
|
| - DumpStats(&printer, level);
|
| - write(STDERR_FILENO, buffer, strlen(buffer));
|
| - delete[] buffer;
|
| -}
|
| -
|
| -static void** DumpStackTraces() {
|
| - // Count how much space we need
|
| - int needed_slots = 0;
|
| - {
|
| - SpinLockHolder h(&pageheap_lock);
|
| - for (Span* s = sampled_objects.next; s != &sampled_objects; s = s->next) {
|
| - StackTrace* stack = reinterpret_cast<StackTrace*>(s->objects);
|
| - needed_slots += 3 + stack->depth;
|
| - }
|
| - needed_slots += 100; // Slop in case sample grows
|
| - needed_slots += needed_slots/8; // An extra 12.5% slop
|
| - }
|
| -
|
| - void** result = new void*[needed_slots];
|
| - if (result == NULL) {
|
| - MESSAGE("tcmalloc: could not allocate %d slots for stack traces\n",
|
| - needed_slots);
|
| - return NULL;
|
| - }
|
| -
|
| - SpinLockHolder h(&pageheap_lock);
|
| - int used_slots = 0;
|
| - for (Span* s = sampled_objects.next; s != &sampled_objects; s = s->next) {
|
| - ASSERT(used_slots < needed_slots); // Need to leave room for terminator
|
| - StackTrace* stack = reinterpret_cast<StackTrace*>(s->objects);
|
| - if (used_slots + 3 + stack->depth >= needed_slots) {
|
| - // No more room
|
| - break;
|
| - }
|
| -
|
| - result[used_slots+0] = reinterpret_cast<void*>(static_cast<uintptr_t>(1));
|
| - result[used_slots+1] = reinterpret_cast<void*>(stack->size);
|
| - result[used_slots+2] = reinterpret_cast<void*>(stack->depth);
|
| - for (int d = 0; d < stack->depth; d++) {
|
| - result[used_slots+3+d] = stack->stack[d];
|
| - }
|
| - used_slots += 3 + stack->depth;
|
| - }
|
| - result[used_slots] = reinterpret_cast<void*>(static_cast<uintptr_t>(0));
|
| - return result;
|
| -}
|
| -#endif
|
| -
|
| -#ifndef WTF_CHANGES
|
| -
|
| -// TCMalloc's support for extra malloc interfaces
|
| -class TCMallocImplementation : public MallocExtension {
|
| - public:
|
| - virtual void GetStats(char* buffer, int buffer_length) {
|
| - ASSERT(buffer_length > 0);
|
| - TCMalloc_Printer printer(buffer, buffer_length);
|
| -
|
| - // Print level one stats unless lots of space is available
|
| - if (buffer_length < 10000) {
|
| - DumpStats(&printer, 1);
|
| - } else {
|
| - DumpStats(&printer, 2);
|
| - }
|
| - }
|
| -
|
| - virtual void** ReadStackTraces() {
|
| - return DumpStackTraces();
|
| - }
|
| -
|
| - virtual bool GetNumericProperty(const char* name, size_t* value) {
|
| - ASSERT(name != NULL);
|
| -
|
| - if (strcmp(name, "generic.current_allocated_bytes") == 0) {
|
| - TCMallocStats stats;
|
| - ExtractStats(&stats, NULL);
|
| - *value = stats.system_bytes
|
| - - stats.thread_bytes
|
| - - stats.central_bytes
|
| - - stats.pageheap_bytes;
|
| - return true;
|
| - }
|
| -
|
| - if (strcmp(name, "generic.heap_size") == 0) {
|
| - TCMallocStats stats;
|
| - ExtractStats(&stats, NULL);
|
| - *value = stats.system_bytes;
|
| - return true;
|
| - }
|
| -
|
| - if (strcmp(name, "tcmalloc.slack_bytes") == 0) {
|
| - // We assume that bytes in the page heap are not fragmented too
|
| - // badly, and are therefore available for allocation.
|
| - SpinLockHolder l(&pageheap_lock);
|
| - *value = pageheap->FreeBytes();
|
| - return true;
|
| - }
|
| -
|
| - if (strcmp(name, "tcmalloc.max_total_thread_cache_bytes") == 0) {
|
| - SpinLockHolder l(&pageheap_lock);
|
| - *value = overall_thread_cache_size;
|
| - return true;
|
| - }
|
| -
|
| - if (strcmp(name, "tcmalloc.current_total_thread_cache_bytes") == 0) {
|
| - TCMallocStats stats;
|
| - ExtractStats(&stats, NULL);
|
| - *value = stats.thread_bytes;
|
| - return true;
|
| - }
|
| -
|
| - return false;
|
| - }
|
| -
|
| - virtual bool SetNumericProperty(const char* name, size_t value) {
|
| - ASSERT(name != NULL);
|
| -
|
| - if (strcmp(name, "tcmalloc.max_total_thread_cache_bytes") == 0) {
|
| - // Clip the value to a reasonable range
|
| - if (value < kMinThreadCacheSize) value = kMinThreadCacheSize;
|
| - if (value > (1<<30)) value = (1<<30); // Limit to 1GB
|
| -
|
| - SpinLockHolder l(&pageheap_lock);
|
| - overall_thread_cache_size = static_cast<size_t>(value);
|
| - TCMalloc_ThreadCache::RecomputeThreadCacheSize();
|
| - return true;
|
| - }
|
| -
|
| - return false;
|
| - }
|
| -
|
| - virtual void MarkThreadIdle() {
|
| - TCMalloc_ThreadCache::BecomeIdle();
|
| - }
|
| -
|
| - virtual void ReleaseFreeMemory() {
|
| - SpinLockHolder h(&pageheap_lock);
|
| - pageheap->ReleaseFreePages();
|
| - }
|
| -};
|
| -#endif
|
| -
|
| -// The constructor allocates an object to ensure that initialization
|
| -// runs before main(), and therefore we do not have a chance to become
|
| -// multi-threaded before initialization. We also create the TSD key
|
| -// here. Presumably by the time this constructor runs, glibc is in
|
| -// good enough shape to handle pthread_key_create().
|
| -//
|
| -// The constructor also takes the opportunity to tell STL to use
|
| -// tcmalloc. We want to do this early, before construct time, so
|
| -// all user STL allocations go through tcmalloc (which works really
|
| -// well for STL).
|
| -//
|
| -// The destructor prints stats when the program exits.
|
| -class TCMallocGuard {
|
| - public:
|
| -
|
| - TCMallocGuard() {
|
| -#ifdef HAVE_TLS // this is true if the cc/ld/libc combo support TLS
|
| - // Check whether the kernel also supports TLS (needs to happen at runtime)
|
| - CheckIfKernelSupportsTLS();
|
| -#endif
|
| -#ifndef WTF_CHANGES
|
| -#ifdef WIN32 // patch the windows VirtualAlloc, etc.
|
| - PatchWindowsFunctions(); // defined in windows/patch_functions.cc
|
| -#endif
|
| -#endif
|
| - free(malloc(1));
|
| - TCMalloc_ThreadCache::InitTSD();
|
| - free(malloc(1));
|
| -#ifndef WTF_CHANGES
|
| - MallocExtension::Register(new TCMallocImplementation);
|
| -#endif
|
| - }
|
| -
|
| -#ifndef WTF_CHANGES
|
| - ~TCMallocGuard() {
|
| - const char* env = getenv("MALLOCSTATS");
|
| - if (env != NULL) {
|
| - int level = atoi(env);
|
| - if (level < 1) level = 1;
|
| - PrintStats(level);
|
| - }
|
| -#ifdef WIN32
|
| - UnpatchWindowsFunctions();
|
| -#endif
|
| - }
|
| -#endif
|
| -};
|
| -
|
| -#ifndef WTF_CHANGES
|
| -static TCMallocGuard module_enter_exit_hook;
|
| -#endif
|
| -
|
| -
|
| -//-------------------------------------------------------------------
|
| -// Helpers for the exported routines below
|
| -//-------------------------------------------------------------------
|
| -
|
| -#ifndef WTF_CHANGES
|
| -
|
| -static Span* DoSampledAllocation(size_t size) {
|
| -
|
| - // Grab the stack trace outside the heap lock
|
| - StackTrace tmp;
|
| - tmp.depth = GetStackTrace(tmp.stack, kMaxStackDepth, 1);
|
| - tmp.size = size;
|
| -
|
| - SpinLockHolder h(&pageheap_lock);
|
| - // Allocate span
|
| - Span *span = pageheap->New(pages(size == 0 ? 1 : size));
|
| - if (span == NULL) {
|
| - return NULL;
|
| - }
|
| -
|
| - // Allocate stack trace
|
| - StackTrace *stack = stacktrace_allocator.New();
|
| - if (stack == NULL) {
|
| - // Sampling failed because of lack of memory
|
| - return span;
|
| - }
|
| -
|
| - *stack = tmp;
|
| - span->sample = 1;
|
| - span->objects = stack;
|
| - DLL_Prepend(&sampled_objects, span);
|
| -
|
| - return span;
|
| -}
|
| -#endif
|
| -
|
| -static inline bool CheckCachedSizeClass(void *ptr) {
|
| - PageID p = reinterpret_cast<uintptr_t>(ptr) >> kPageShift;
|
| - size_t cached_value = pageheap->GetSizeClassIfCached(p);
|
| - return cached_value == 0 ||
|
| - cached_value == pageheap->GetDescriptor(p)->sizeclass;
|
| -}
|
| -
|
| -static inline void* CheckedMallocResult(void *result)
|
| -{
|
| - ASSERT(result == 0 || CheckCachedSizeClass(result));
|
| - return result;
|
| -}
|
| -
|
| -static inline void* SpanToMallocResult(Span *span) {
|
| - ASSERT_SPAN_COMMITTED(span);
|
| - pageheap->CacheSizeClass(span->start, 0);
|
| - void* result = reinterpret_cast<void*>(span->start << kPageShift);
|
| - POISON_ALLOCATION(result, span->length << kPageShift);
|
| - return CheckedMallocResult(result);
|
| -}
|
| -
|
| -#ifdef WTF_CHANGES
|
| -template <bool crashOnFailure>
|
| -#endif
|
| -static ALWAYS_INLINE void* do_malloc(size_t size) {
|
| - void* ret = NULL;
|
| -
|
| -#ifdef WTF_CHANGES
|
| - ASSERT(!isForbidden());
|
| -#endif
|
| -
|
| - // The following call forces module initialization
|
| - TCMalloc_ThreadCache* heap = TCMalloc_ThreadCache::GetCache();
|
| -#ifndef WTF_CHANGES
|
| - if ((FLAGS_tcmalloc_sample_parameter > 0) && heap->SampleAllocation(size)) {
|
| - Span* span = DoSampledAllocation(size);
|
| - if (span != NULL) {
|
| - ret = SpanToMallocResult(span);
|
| - }
|
| - } else
|
| -#endif
|
| - if (size > kMaxSize) {
|
| - // Use page-level allocator
|
| - SpinLockHolder h(&pageheap_lock);
|
| - Span* span = pageheap->New(pages(size));
|
| - if (span != NULL) {
|
| - ret = SpanToMallocResult(span);
|
| - }
|
| - } else {
|
| - // The common case, and also the simplest. This just pops the
|
| - // size-appropriate freelist, afer replenishing it if it's empty.
|
| - ret = CheckedMallocResult(heap->Allocate(size));
|
| - }
|
| - if (!ret) {
|
| -#ifdef WTF_CHANGES
|
| - if (crashOnFailure) // This branch should be optimized out by the compiler.
|
| - CRASH();
|
| -#else
|
| - errno = ENOMEM;
|
| -#endif
|
| - }
|
| - return ret;
|
| -}
|
| -
|
| -static ALWAYS_INLINE void do_free(void* ptr) {
|
| - if (ptr == NULL) return;
|
| - ASSERT(pageheap != NULL); // Should not call free() before malloc()
|
| - const PageID p = reinterpret_cast<uintptr_t>(ptr) >> kPageShift;
|
| - Span* span = NULL;
|
| - size_t cl = pageheap->GetSizeClassIfCached(p);
|
| -
|
| - if (cl == 0) {
|
| - span = pageheap->GetDescriptor(p);
|
| - RELEASE_ASSERT(span->isValid());
|
| - cl = span->sizeclass;
|
| - pageheap->CacheSizeClass(p, cl);
|
| - }
|
| - if (cl != 0) {
|
| -#ifndef NO_TCMALLOC_SAMPLES
|
| - ASSERT(!pageheap->GetDescriptor(p)->sample);
|
| -#endif
|
| - TCMalloc_ThreadCache* heap = TCMalloc_ThreadCache::GetCacheIfPresent();
|
| - if (heap != NULL) {
|
| - heap->Deallocate(HardenedSLL::create(ptr), cl);
|
| - } else {
|
| - // Delete directly into central cache
|
| - POISON_DEALLOCATION(ptr, ByteSizeForClass(cl));
|
| - SLL_SetNext(HardenedSLL::create(ptr), HardenedSLL::null(), central_cache[cl].entropy());
|
| - central_cache[cl].InsertRange(HardenedSLL::create(ptr), HardenedSLL::create(ptr), 1);
|
| - }
|
| - } else {
|
| - SpinLockHolder h(&pageheap_lock);
|
| - ASSERT(reinterpret_cast<uintptr_t>(ptr) % kPageSize == 0);
|
| - ASSERT(span != NULL && span->start == p);
|
| -#ifndef NO_TCMALLOC_SAMPLES
|
| - if (span->sample) {
|
| - DLL_Remove(span);
|
| - stacktrace_allocator.Delete(reinterpret_cast<StackTrace*>(span->objects));
|
| - span->objects = NULL;
|
| - }
|
| -#endif
|
| -
|
| - POISON_DEALLOCATION(ptr, span->length << kPageShift);
|
| - pageheap->Delete(span);
|
| - }
|
| -}
|
| -
|
| -#ifndef WTF_CHANGES
|
| -// For use by exported routines below that want specific alignments
|
| -//
|
| -// Note: this code can be slow, and can significantly fragment memory.
|
| -// The expectation is that memalign/posix_memalign/valloc/pvalloc will
|
| -// not be invoked very often. This requirement simplifies our
|
| -// implementation and allows us to tune for expected allocation
|
| -// patterns.
|
| -static void* do_memalign(size_t align, size_t size) {
|
| - ASSERT((align & (align - 1)) == 0);
|
| - ASSERT(align > 0);
|
| - if (pageheap == NULL) TCMalloc_ThreadCache::InitModule();
|
| -
|
| - // Allocate at least one byte to avoid boundary conditions below
|
| - if (size == 0) size = 1;
|
| -
|
| - if (size <= kMaxSize && align < kPageSize) {
|
| - // Search through acceptable size classes looking for one with
|
| - // enough alignment. This depends on the fact that
|
| - // InitSizeClasses() currently produces several size classes that
|
| - // are aligned at powers of two. We will waste time and space if
|
| - // we miss in the size class array, but that is deemed acceptable
|
| - // since memalign() should be used rarely.
|
| - size_t cl = SizeClass(size);
|
| - while (cl < kNumClasses && ((class_to_size[cl] & (align - 1)) != 0)) {
|
| - cl++;
|
| - }
|
| - if (cl < kNumClasses) {
|
| - TCMalloc_ThreadCache* heap = TCMalloc_ThreadCache::GetCache();
|
| - return CheckedMallocResult(heap->Allocate(class_to_size[cl]));
|
| - }
|
| - }
|
| -
|
| - // We will allocate directly from the page heap
|
| - SpinLockHolder h(&pageheap_lock);
|
| -
|
| - if (align <= kPageSize) {
|
| - // Any page-level allocation will be fine
|
| - // TODO: We could put the rest of this page in the appropriate
|
| - // TODO: cache but it does not seem worth it.
|
| - Span* span = pageheap->New(pages(size));
|
| - return span == NULL ? NULL : SpanToMallocResult(span);
|
| - }
|
| -
|
| - // Allocate extra pages and carve off an aligned portion
|
| - const Length alloc = pages(size + align);
|
| - Span* span = pageheap->New(alloc);
|
| - if (span == NULL) return NULL;
|
| -
|
| - // Skip starting portion so that we end up aligned
|
| - Length skip = 0;
|
| - while ((((span->start+skip) << kPageShift) & (align - 1)) != 0) {
|
| - skip++;
|
| - }
|
| - ASSERT(skip < alloc);
|
| - if (skip > 0) {
|
| - Span* rest = pageheap->Split(span, skip);
|
| - pageheap->Delete(span);
|
| - span = rest;
|
| - }
|
| -
|
| - // Skip trailing portion that we do not need to return
|
| - const Length needed = pages(size);
|
| - ASSERT(span->length >= needed);
|
| - if (span->length > needed) {
|
| - Span* trailer = pageheap->Split(span, needed);
|
| - pageheap->Delete(trailer);
|
| - }
|
| - return SpanToMallocResult(span);
|
| -}
|
| -#endif
|
| -
|
| -// Helpers for use by exported routines below:
|
| -
|
| -#ifndef WTF_CHANGES
|
| -static inline void do_malloc_stats() {
|
| - PrintStats(1);
|
| -}
|
| -#endif
|
| -
|
| -static inline int do_mallopt(int, int) {
|
| - return 1; // Indicates error
|
| -}
|
| -
|
| -#ifdef HAVE_STRUCT_MALLINFO // mallinfo isn't defined on freebsd, for instance
|
| -static inline struct mallinfo do_mallinfo() {
|
| - TCMallocStats stats;
|
| - ExtractStats(&stats, NULL);
|
| -
|
| - // Just some of the fields are filled in.
|
| - struct mallinfo info;
|
| - memset(&info, 0, sizeof(info));
|
| -
|
| - // Unfortunately, the struct contains "int" field, so some of the
|
| - // size values will be truncated.
|
| - info.arena = static_cast<int>(stats.system_bytes);
|
| - info.fsmblks = static_cast<int>(stats.thread_bytes
|
| - + stats.central_bytes
|
| - + stats.transfer_bytes);
|
| - info.fordblks = static_cast<int>(stats.pageheap_bytes);
|
| - info.uordblks = static_cast<int>(stats.system_bytes
|
| - - stats.thread_bytes
|
| - - stats.central_bytes
|
| - - stats.transfer_bytes
|
| - - stats.pageheap_bytes);
|
| -
|
| - return info;
|
| -}
|
| -#endif
|
| -
|
| -//-------------------------------------------------------------------
|
| -// Exported routines
|
| -//-------------------------------------------------------------------
|
| -
|
| -// CAVEAT: The code structure below ensures that MallocHook methods are always
|
| -// called from the stack frame of the invoked allocation function.
|
| -// heap-checker.cc depends on this to start a stack trace from
|
| -// the call to the (de)allocation function.
|
| -
|
| -#ifndef WTF_CHANGES
|
| -extern "C"
|
| -#else
|
| -#define do_malloc do_malloc<crashOnFailure>
|
| -
|
| -template <bool crashOnFailure>
|
| -ALWAYS_INLINE void* malloc(size_t);
|
| -
|
| -void* fastMalloc(size_t size)
|
| -{
|
| - return malloc<true>(size);
|
| -}
|
| -
|
| -TryMallocReturnValue tryFastMalloc(size_t size)
|
| -{
|
| - return malloc<false>(size);
|
| -}
|
| -
|
| -template <bool crashOnFailure>
|
| -ALWAYS_INLINE
|
| -#endif
|
| -void* malloc(size_t size) {
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - if (std::numeric_limits<size_t>::max() - Internal::ValidationBufferSize <= size) // If overflow would occur...
|
| - return 0;
|
| - void* result = do_malloc(size + Internal::ValidationBufferSize);
|
| - if (!result)
|
| - return 0;
|
| -
|
| - Internal::ValidationHeader* header = static_cast<Internal::ValidationHeader*>(result);
|
| - header->m_size = size;
|
| - header->m_type = Internal::AllocTypeMalloc;
|
| - header->m_prefix = static_cast<unsigned>(Internal::ValidationPrefix);
|
| - result = header + 1;
|
| - *Internal::fastMallocValidationSuffix(result) = Internal::ValidationSuffix;
|
| - fastMallocValidate(result);
|
| -#else
|
| - void* result = do_malloc(size);
|
| -#endif
|
| -
|
| -#ifndef WTF_CHANGES
|
| - MallocHook::InvokeNewHook(result, size);
|
| -#endif
|
| - return result;
|
| -}
|
| -
|
| -#ifndef WTF_CHANGES
|
| -extern "C"
|
| -#endif
|
| -void free(void* ptr) {
|
| -#ifndef WTF_CHANGES
|
| - MallocHook::InvokeDeleteHook(ptr);
|
| -#endif
|
| -
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - if (!ptr)
|
| - return;
|
| -
|
| - fastMallocValidate(ptr);
|
| - Internal::ValidationHeader* header = Internal::fastMallocValidationHeader(ptr);
|
| - memset(ptr, 0xCC, header->m_size);
|
| - do_free(header);
|
| -#else
|
| - do_free(ptr);
|
| -#endif
|
| -}
|
| -
|
| -#ifndef WTF_CHANGES
|
| -extern "C"
|
| -#else
|
| -template <bool crashOnFailure>
|
| -ALWAYS_INLINE void* calloc(size_t, size_t);
|
| -
|
| -void* fastCalloc(size_t n, size_t elem_size)
|
| -{
|
| - void* result = calloc<true>(n, elem_size);
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - fastMallocValidate(result);
|
| -#endif
|
| - return result;
|
| -}
|
| -
|
| -TryMallocReturnValue tryFastCalloc(size_t n, size_t elem_size)
|
| -{
|
| - void* result = calloc<false>(n, elem_size);
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - fastMallocValidate(result);
|
| -#endif
|
| - return result;
|
| -}
|
| -
|
| -template <bool crashOnFailure>
|
| -ALWAYS_INLINE
|
| -#endif
|
| -void* calloc(size_t n, size_t elem_size) {
|
| - size_t totalBytes = n * elem_size;
|
| -
|
| - // Protect against overflow
|
| - if (n > 1 && elem_size && (totalBytes / elem_size) != n)
|
| - return 0;
|
| -
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - void* result = malloc<crashOnFailure>(totalBytes);
|
| - if (!result)
|
| - return 0;
|
| -
|
| - memset(result, 0, totalBytes);
|
| - fastMallocValidate(result);
|
| -#else
|
| - void* result = do_malloc(totalBytes);
|
| - if (result != NULL) {
|
| - memset(result, 0, totalBytes);
|
| - }
|
| -#endif
|
| -
|
| -#ifndef WTF_CHANGES
|
| - MallocHook::InvokeNewHook(result, totalBytes);
|
| -#endif
|
| - return result;
|
| -}
|
| -
|
| -// Since cfree isn't used anywhere, we don't compile it in.
|
| -#ifndef WTF_CHANGES
|
| -#ifndef WTF_CHANGES
|
| -extern "C"
|
| -#endif
|
| -void cfree(void* ptr) {
|
| -#ifndef WTF_CHANGES
|
| - MallocHook::InvokeDeleteHook(ptr);
|
| -#endif
|
| - do_free(ptr);
|
| -}
|
| -#endif
|
| -
|
| -#ifndef WTF_CHANGES
|
| -extern "C"
|
| -#else
|
| -template <bool crashOnFailure>
|
| -ALWAYS_INLINE void* realloc(void*, size_t);
|
| -
|
| -void* fastRealloc(void* old_ptr, size_t new_size)
|
| -{
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - fastMallocValidate(old_ptr);
|
| -#endif
|
| - void* result = realloc<true>(old_ptr, new_size);
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - fastMallocValidate(result);
|
| -#endif
|
| - return result;
|
| -}
|
| -
|
| -TryMallocReturnValue tryFastRealloc(void* old_ptr, size_t new_size)
|
| -{
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - fastMallocValidate(old_ptr);
|
| -#endif
|
| - void* result = realloc<false>(old_ptr, new_size);
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - fastMallocValidate(result);
|
| -#endif
|
| - return result;
|
| -}
|
| -
|
| -template <bool crashOnFailure>
|
| -ALWAYS_INLINE
|
| -#endif
|
| -void* realloc(void* old_ptr, size_t new_size) {
|
| - if (old_ptr == NULL) {
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - void* result = malloc<crashOnFailure>(new_size);
|
| -#else
|
| - void* result = do_malloc(new_size);
|
| -#ifndef WTF_CHANGES
|
| - MallocHook::InvokeNewHook(result, new_size);
|
| -#endif
|
| -#endif
|
| - return result;
|
| - }
|
| - if (new_size == 0) {
|
| -#ifndef WTF_CHANGES
|
| - MallocHook::InvokeDeleteHook(old_ptr);
|
| -#endif
|
| - free(old_ptr);
|
| - return NULL;
|
| - }
|
| -
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - if (std::numeric_limits<size_t>::max() - Internal::ValidationBufferSize <= new_size) // If overflow would occur...
|
| - return 0;
|
| - Internal::ValidationHeader* header = Internal::fastMallocValidationHeader(old_ptr);
|
| - fastMallocValidate(old_ptr);
|
| - old_ptr = header;
|
| - header->m_size = new_size;
|
| - new_size += Internal::ValidationBufferSize;
|
| -#endif
|
| -
|
| - // Get the size of the old entry
|
| - const PageID p = reinterpret_cast<uintptr_t>(old_ptr) >> kPageShift;
|
| - size_t cl = pageheap->GetSizeClassIfCached(p);
|
| - Span *span = NULL;
|
| - size_t old_size;
|
| - if (cl == 0) {
|
| - span = pageheap->GetDescriptor(p);
|
| - cl = span->sizeclass;
|
| - pageheap->CacheSizeClass(p, cl);
|
| - }
|
| - if (cl != 0) {
|
| - old_size = ByteSizeForClass(cl);
|
| - } else {
|
| - ASSERT(span != NULL);
|
| - old_size = span->length << kPageShift;
|
| - }
|
| -
|
| - // Reallocate if the new size is larger than the old size,
|
| - // or if the new size is significantly smaller than the old size.
|
| - if ((new_size > old_size) || (AllocationSize(new_size) < old_size)) {
|
| - // Need to reallocate
|
| - void* new_ptr = do_malloc(new_size);
|
| - if (new_ptr == NULL) {
|
| - return NULL;
|
| - }
|
| -#ifndef WTF_CHANGES
|
| - MallocHook::InvokeNewHook(new_ptr, new_size);
|
| -#endif
|
| - memcpy(new_ptr, old_ptr, ((old_size < new_size) ? old_size : new_size));
|
| -#ifndef WTF_CHANGES
|
| - MallocHook::InvokeDeleteHook(old_ptr);
|
| -#endif
|
| - // We could use a variant of do_free() that leverages the fact
|
| - // that we already know the sizeclass of old_ptr. The benefit
|
| - // would be small, so don't bother.
|
| - do_free(old_ptr);
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - new_ptr = static_cast<Internal::ValidationHeader*>(new_ptr) + 1;
|
| - *Internal::fastMallocValidationSuffix(new_ptr) = Internal::ValidationSuffix;
|
| -#endif
|
| - return new_ptr;
|
| - } else {
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - old_ptr = static_cast<Internal::ValidationHeader*>(old_ptr) + 1; // Set old_ptr back to the user pointer.
|
| - *Internal::fastMallocValidationSuffix(old_ptr) = Internal::ValidationSuffix;
|
| -#endif
|
| - return old_ptr;
|
| - }
|
| -}
|
| -
|
| -#ifdef WTF_CHANGES
|
| -#undef do_malloc
|
| -#else
|
| -
|
| -static SpinLock set_new_handler_lock = SPINLOCK_INITIALIZER;
|
| -
|
| -static inline void* cpp_alloc(size_t size, bool nothrow) {
|
| - for (;;) {
|
| - void* p = do_malloc(size);
|
| -#ifdef PREANSINEW
|
| - return p;
|
| -#else
|
| - if (p == NULL) { // allocation failed
|
| - // Get the current new handler. NB: this function is not
|
| - // thread-safe. We make a feeble stab at making it so here, but
|
| - // this lock only protects against tcmalloc interfering with
|
| - // itself, not with other libraries calling set_new_handler.
|
| - std::new_handler nh;
|
| - {
|
| - SpinLockHolder h(&set_new_handler_lock);
|
| - nh = std::set_new_handler(0);
|
| - (void) std::set_new_handler(nh);
|
| - }
|
| - // If no new_handler is established, the allocation failed.
|
| - if (!nh) {
|
| - if (nothrow) return 0;
|
| - throw std::bad_alloc();
|
| - }
|
| - // Otherwise, try the new_handler. If it returns, retry the
|
| - // allocation. If it throws std::bad_alloc, fail the allocation.
|
| - // if it throws something else, don't interfere.
|
| - try {
|
| - (*nh)();
|
| - } catch (const std::bad_alloc&) {
|
| - if (!nothrow) throw;
|
| - return p;
|
| - }
|
| - } else { // allocation success
|
| - return p;
|
| - }
|
| -#endif
|
| - }
|
| -}
|
| -
|
| -extern "C" void* memalign(size_t align, size_t size) __THROW {
|
| - void* result = do_memalign(align, size);
|
| - MallocHook::InvokeNewHook(result, size);
|
| - return result;
|
| -}
|
| -
|
| -extern "C" int posix_memalign(void** result_ptr, size_t align, size_t size)
|
| - __THROW {
|
| - if (((align % sizeof(void*)) != 0) ||
|
| - ((align & (align - 1)) != 0) ||
|
| - (align == 0)) {
|
| - return EINVAL;
|
| - }
|
| -
|
| - void* result = do_memalign(align, size);
|
| - MallocHook::InvokeNewHook(result, size);
|
| - if (result == NULL) {
|
| - return ENOMEM;
|
| - } else {
|
| - *result_ptr = result;
|
| - return 0;
|
| - }
|
| -}
|
| -
|
| -static size_t pagesize = 0;
|
| -
|
| -extern "C" void* valloc(size_t size) __THROW {
|
| - // Allocate page-aligned object of length >= size bytes
|
| - if (pagesize == 0) pagesize = getpagesize();
|
| - void* result = do_memalign(pagesize, size);
|
| - MallocHook::InvokeNewHook(result, size);
|
| - return result;
|
| -}
|
| -
|
| -extern "C" void* pvalloc(size_t size) __THROW {
|
| - // Round up size to a multiple of pagesize
|
| - if (pagesize == 0) pagesize = getpagesize();
|
| - size = (size + pagesize - 1) & ~(pagesize - 1);
|
| - void* result = do_memalign(pagesize, size);
|
| - MallocHook::InvokeNewHook(result, size);
|
| - return result;
|
| -}
|
| -
|
| -extern "C" void malloc_stats(void) {
|
| - do_malloc_stats();
|
| -}
|
| -
|
| -extern "C" int mallopt(int cmd, int value) {
|
| - return do_mallopt(cmd, value);
|
| -}
|
| -
|
| -#ifdef HAVE_STRUCT_MALLINFO
|
| -extern "C" struct mallinfo mallinfo(void) {
|
| - return do_mallinfo();
|
| -}
|
| -#endif
|
| -
|
| -//-------------------------------------------------------------------
|
| -// Some library routines on RedHat 9 allocate memory using malloc()
|
| -// and free it using __libc_free() (or vice-versa). Since we provide
|
| -// our own implementations of malloc/free, we need to make sure that
|
| -// the __libc_XXX variants (defined as part of glibc) also point to
|
| -// the same implementations.
|
| -//-------------------------------------------------------------------
|
| -
|
| -#if defined(__GLIBC__)
|
| -extern "C" {
|
| -#if COMPILER(GCC) && !defined(__MACH__) && defined(HAVE___ATTRIBUTE__)
|
| - // Potentially faster variants that use the gcc alias extension.
|
| - // Mach-O (Darwin) does not support weak aliases, hence the __MACH__ check.
|
| -# define ALIAS(x) __attribute__ ((weak, alias (x)))
|
| - void* __libc_malloc(size_t size) ALIAS("malloc");
|
| - void __libc_free(void* ptr) ALIAS("free");
|
| - void* __libc_realloc(void* ptr, size_t size) ALIAS("realloc");
|
| - void* __libc_calloc(size_t n, size_t size) ALIAS("calloc");
|
| - void __libc_cfree(void* ptr) ALIAS("cfree");
|
| - void* __libc_memalign(size_t align, size_t s) ALIAS("memalign");
|
| - void* __libc_valloc(size_t size) ALIAS("valloc");
|
| - void* __libc_pvalloc(size_t size) ALIAS("pvalloc");
|
| - int __posix_memalign(void** r, size_t a, size_t s) ALIAS("posix_memalign");
|
| -# undef ALIAS
|
| -# else /* not __GNUC__ */
|
| - // Portable wrappers
|
| - void* __libc_malloc(size_t size) { return malloc(size); }
|
| - void __libc_free(void* ptr) { free(ptr); }
|
| - void* __libc_realloc(void* ptr, size_t size) { return realloc(ptr, size); }
|
| - void* __libc_calloc(size_t n, size_t size) { return calloc(n, size); }
|
| - void __libc_cfree(void* ptr) { cfree(ptr); }
|
| - void* __libc_memalign(size_t align, size_t s) { return memalign(align, s); }
|
| - void* __libc_valloc(size_t size) { return valloc(size); }
|
| - void* __libc_pvalloc(size_t size) { return pvalloc(size); }
|
| - int __posix_memalign(void** r, size_t a, size_t s) {
|
| - return posix_memalign(r, a, s);
|
| - }
|
| -# endif /* __GNUC__ */
|
| -}
|
| -#endif /* __GLIBC__ */
|
| -
|
| -// Override __libc_memalign in libc on linux boxes specially.
|
| -// They have a bug in libc that causes them to (very rarely) allocate
|
| -// with __libc_memalign() yet deallocate with free() and the
|
| -// definitions above don't catch it.
|
| -// This function is an exception to the rule of calling MallocHook method
|
| -// from the stack frame of the allocation function;
|
| -// heap-checker handles this special case explicitly.
|
| -static void *MemalignOverride(size_t align, size_t size, const void *caller)
|
| - __THROW {
|
| - void* result = do_memalign(align, size);
|
| - MallocHook::InvokeNewHook(result, size);
|
| - return result;
|
| -}
|
| -void *(*__memalign_hook)(size_t, size_t, const void *) = MemalignOverride;
|
| -
|
| -#endif
|
| -
|
| -#ifdef WTF_CHANGES
|
| -void releaseFastMallocFreeMemory()
|
| -{
|
| - // Flush free pages in the current thread cache back to the page heap.
|
| - if (TCMalloc_ThreadCache* threadCache = TCMalloc_ThreadCache::GetCacheIfPresent())
|
| - threadCache->Cleanup();
|
| -
|
| - SpinLockHolder h(&pageheap_lock);
|
| - pageheap->ReleaseFreePages();
|
| -}
|
| -
|
| -FastMallocStatistics fastMallocStatistics()
|
| -{
|
| - FastMallocStatistics statistics;
|
| -
|
| - SpinLockHolder lockHolder(&pageheap_lock);
|
| - statistics.reservedVMBytes = static_cast<size_t>(pageheap->SystemBytes());
|
| - statistics.committedVMBytes = statistics.reservedVMBytes - pageheap->ReturnedBytes();
|
| -
|
| - statistics.freeListBytes = 0;
|
| - for (unsigned cl = 0; cl < kNumClasses; ++cl) {
|
| - const int length = central_cache[cl].length();
|
| - const int tc_length = central_cache[cl].tc_length();
|
| -
|
| - statistics.freeListBytes += ByteSizeForClass(cl) * (length + tc_length);
|
| - }
|
| - for (TCMalloc_ThreadCache* threadCache = thread_heaps; threadCache ; threadCache = threadCache->next_)
|
| - statistics.freeListBytes += threadCache->Size();
|
| -
|
| - return statistics;
|
| -}
|
| -
|
| -size_t fastMallocSize(const void* ptr)
|
| -{
|
| -#if ENABLE(WTF_MALLOC_VALIDATION)
|
| - return Internal::fastMallocValidationHeader(const_cast<void*>(ptr))->m_size;
|
| -#else
|
| - const PageID p = reinterpret_cast<uintptr_t>(ptr) >> kPageShift;
|
| - Span* span = pageheap->GetDescriptorEnsureSafe(p);
|
| -
|
| - if (!span || span->free)
|
| - return 0;
|
| -
|
| - for (HardenedSLL free = span->objects; free; free = SLL_Next(free, HARDENING_ENTROPY)) {
|
| - if (ptr == free.value())
|
| - return 0;
|
| - }
|
| -
|
| - if (size_t cl = span->sizeclass)
|
| - return ByteSizeForClass(cl);
|
| -
|
| - return span->length << kPageShift;
|
| -#endif
|
| -}
|
| -
|
| -#if OS(DARWIN)
|
| -
|
| -template <typename T>
|
| -T* RemoteMemoryReader::nextEntryInHardenedLinkedList(T** remoteAddress, uintptr_t entropy) const
|
| -{
|
| - T** localAddress = (*this)(remoteAddress);
|
| - if (!localAddress)
|
| - return 0;
|
| - T* hardenedNext = *localAddress;
|
| - if (!hardenedNext || hardenedNext == (void*)entropy)
|
| - return 0;
|
| - return XOR_MASK_PTR_WITH_KEY(hardenedNext, remoteAddress, entropy);
|
| -}
|
| -
|
| -class FreeObjectFinder {
|
| - const RemoteMemoryReader& m_reader;
|
| - HashSet<void*> m_freeObjects;
|
| -
|
| -public:
|
| - FreeObjectFinder(const RemoteMemoryReader& reader) : m_reader(reader) { }
|
| -
|
| - void visit(void* ptr) { m_freeObjects.add(ptr); }
|
| - bool isFreeObject(void* ptr) const { return m_freeObjects.contains(ptr); }
|
| - bool isFreeObject(vm_address_t ptr) const { return isFreeObject(reinterpret_cast<void*>(ptr)); }
|
| - size_t freeObjectCount() const { return m_freeObjects.size(); }
|
| -
|
| - void findFreeObjects(TCMalloc_ThreadCache* threadCache)
|
| - {
|
| - for (; threadCache; threadCache = (threadCache->next_ ? m_reader(threadCache->next_) : 0))
|
| - threadCache->enumerateFreeObjects(*this, m_reader);
|
| - }
|
| -
|
| - void findFreeObjects(TCMalloc_Central_FreeListPadded* centralFreeList, size_t numSizes, TCMalloc_Central_FreeListPadded* remoteCentralFreeList)
|
| - {
|
| - for (unsigned i = 0; i < numSizes; i++)
|
| - centralFreeList[i].enumerateFreeObjects(*this, m_reader, remoteCentralFreeList + i);
|
| - }
|
| -};
|
| -
|
| -class PageMapFreeObjectFinder {
|
| - const RemoteMemoryReader& m_reader;
|
| - FreeObjectFinder& m_freeObjectFinder;
|
| - uintptr_t m_entropy;
|
| -
|
| -public:
|
| - PageMapFreeObjectFinder(const RemoteMemoryReader& reader, FreeObjectFinder& freeObjectFinder, uintptr_t entropy)
|
| - : m_reader(reader)
|
| - , m_freeObjectFinder(freeObjectFinder)
|
| - , m_entropy(entropy)
|
| - {
|
| -#if ENABLE(TCMALLOC_HARDENING)
|
| - ASSERT(m_entropy);
|
| -#endif
|
| - }
|
| -
|
| - int visit(void* ptr) const
|
| - {
|
| - if (!ptr)
|
| - return 1;
|
| -
|
| - Span* span = m_reader(reinterpret_cast<Span*>(ptr));
|
| - if (!span)
|
| - return 1;
|
| -
|
| - if (span->free) {
|
| - void* ptr = reinterpret_cast<void*>(span->start << kPageShift);
|
| - m_freeObjectFinder.visit(ptr);
|
| - } else if (span->sizeclass) {
|
| - // Walk the free list of the small-object span, keeping track of each object seen
|
| - for (HardenedSLL nextObject = span->objects; nextObject; nextObject.setValue(m_reader.nextEntryInHardenedLinkedList(reinterpret_cast<void**>(nextObject.value()), m_entropy)))
|
| - m_freeObjectFinder.visit(nextObject.value());
|
| - }
|
| - return span->length;
|
| - }
|
| -};
|
| -
|
| -class PageMapMemoryUsageRecorder {
|
| - task_t m_task;
|
| - void* m_context;
|
| - unsigned m_typeMask;
|
| - vm_range_recorder_t* m_recorder;
|
| - const RemoteMemoryReader& m_reader;
|
| - const FreeObjectFinder& m_freeObjectFinder;
|
| -
|
| - HashSet<void*> m_seenPointers;
|
| - Vector<Span*> m_coalescedSpans;
|
| -
|
| -public:
|
| - PageMapMemoryUsageRecorder(task_t task, void* context, unsigned typeMask, vm_range_recorder_t* recorder, const RemoteMemoryReader& reader, const FreeObjectFinder& freeObjectFinder)
|
| - : m_task(task)
|
| - , m_context(context)
|
| - , m_typeMask(typeMask)
|
| - , m_recorder(recorder)
|
| - , m_reader(reader)
|
| - , m_freeObjectFinder(freeObjectFinder)
|
| - { }
|
| -
|
| - ~PageMapMemoryUsageRecorder()
|
| - {
|
| - ASSERT(!m_coalescedSpans.size());
|
| - }
|
| -
|
| - void recordPendingRegions()
|
| - {
|
| - if (!(m_typeMask & (MALLOC_PTR_IN_USE_RANGE_TYPE | MALLOC_PTR_REGION_RANGE_TYPE))) {
|
| - m_coalescedSpans.clear();
|
| - return;
|
| - }
|
| -
|
| - Vector<vm_range_t, 1024> allocatedPointers;
|
| - for (size_t i = 0; i < m_coalescedSpans.size(); ++i) {
|
| - Span *theSpan = m_coalescedSpans[i];
|
| - if (theSpan->free)
|
| - continue;
|
| -
|
| - vm_address_t spanStartAddress = theSpan->start << kPageShift;
|
| - vm_size_t spanSizeInBytes = theSpan->length * kPageSize;
|
| -
|
| - if (!theSpan->sizeclass) {
|
| - // If it's an allocated large object span, mark it as in use
|
| - if (!m_freeObjectFinder.isFreeObject(spanStartAddress))
|
| - allocatedPointers.append((vm_range_t){spanStartAddress, spanSizeInBytes});
|
| - } else {
|
| - const size_t objectSize = ByteSizeForClass(theSpan->sizeclass);
|
| -
|
| - // Mark each allocated small object within the span as in use
|
| - const vm_address_t endOfSpan = spanStartAddress + spanSizeInBytes;
|
| - for (vm_address_t object = spanStartAddress; object + objectSize <= endOfSpan; object += objectSize) {
|
| - if (!m_freeObjectFinder.isFreeObject(object))
|
| - allocatedPointers.append((vm_range_t){object, objectSize});
|
| - }
|
| - }
|
| - }
|
| -
|
| - (*m_recorder)(m_task, m_context, m_typeMask & (MALLOC_PTR_IN_USE_RANGE_TYPE | MALLOC_PTR_REGION_RANGE_TYPE), allocatedPointers.data(), allocatedPointers.size());
|
| -
|
| - m_coalescedSpans.clear();
|
| - }
|
| -
|
| - int visit(void* ptr)
|
| - {
|
| - if (!ptr)
|
| - return 1;
|
| -
|
| - Span* span = m_reader(reinterpret_cast<Span*>(ptr));
|
| - if (!span || !span->start)
|
| - return 1;
|
| -
|
| - if (m_seenPointers.contains(ptr))
|
| - return span->length;
|
| - m_seenPointers.add(ptr);
|
| -
|
| - if (!m_coalescedSpans.size()) {
|
| - m_coalescedSpans.append(span);
|
| - return span->length;
|
| - }
|
| -
|
| - Span* previousSpan = m_coalescedSpans[m_coalescedSpans.size() - 1];
|
| - vm_address_t previousSpanStartAddress = previousSpan->start << kPageShift;
|
| - vm_size_t previousSpanSizeInBytes = previousSpan->length * kPageSize;
|
| -
|
| - // If the new span is adjacent to the previous span, do nothing for now.
|
| - vm_address_t spanStartAddress = span->start << kPageShift;
|
| - if (spanStartAddress == previousSpanStartAddress + previousSpanSizeInBytes) {
|
| - m_coalescedSpans.append(span);
|
| - return span->length;
|
| - }
|
| -
|
| - // New span is not adjacent to previous span, so record the spans coalesced so far.
|
| - recordPendingRegions();
|
| - m_coalescedSpans.append(span);
|
| -
|
| - return span->length;
|
| - }
|
| -};
|
| -
|
| -class AdminRegionRecorder {
|
| - task_t m_task;
|
| - void* m_context;
|
| - unsigned m_typeMask;
|
| - vm_range_recorder_t* m_recorder;
|
| -
|
| - Vector<vm_range_t, 1024> m_pendingRegions;
|
| -
|
| -public:
|
| - AdminRegionRecorder(task_t task, void* context, unsigned typeMask, vm_range_recorder_t* recorder)
|
| - : m_task(task)
|
| - , m_context(context)
|
| - , m_typeMask(typeMask)
|
| - , m_recorder(recorder)
|
| - { }
|
| -
|
| - void recordRegion(vm_address_t ptr, size_t size)
|
| - {
|
| - if (m_typeMask & MALLOC_ADMIN_REGION_RANGE_TYPE)
|
| - m_pendingRegions.append((vm_range_t){ ptr, size });
|
| - }
|
| -
|
| - void visit(void *ptr, size_t size)
|
| - {
|
| - recordRegion(reinterpret_cast<vm_address_t>(ptr), size);
|
| - }
|
| -
|
| - void recordPendingRegions()
|
| - {
|
| - if (m_pendingRegions.size()) {
|
| - (*m_recorder)(m_task, m_context, MALLOC_ADMIN_REGION_RANGE_TYPE, m_pendingRegions.data(), m_pendingRegions.size());
|
| - m_pendingRegions.clear();
|
| - }
|
| - }
|
| -
|
| - ~AdminRegionRecorder()
|
| - {
|
| - ASSERT(!m_pendingRegions.size());
|
| - }
|
| -};
|
| -
|
| -kern_return_t FastMallocZone::enumerate(task_t task, void* context, unsigned typeMask, vm_address_t zoneAddress, memory_reader_t reader, vm_range_recorder_t recorder)
|
| -{
|
| - RemoteMemoryReader memoryReader(task, reader);
|
| -
|
| - InitSizeClasses();
|
| -
|
| - FastMallocZone* mzone = memoryReader(reinterpret_cast<FastMallocZone*>(zoneAddress));
|
| - TCMalloc_PageHeap* pageHeap = memoryReader(mzone->m_pageHeap);
|
| - TCMalloc_ThreadCache** threadHeapsPointer = memoryReader(mzone->m_threadHeaps);
|
| - TCMalloc_ThreadCache* threadHeaps = memoryReader(*threadHeapsPointer);
|
| -
|
| - TCMalloc_Central_FreeListPadded* centralCaches = memoryReader(mzone->m_centralCaches, sizeof(TCMalloc_Central_FreeListPadded) * kNumClasses);
|
| -
|
| - FreeObjectFinder finder(memoryReader);
|
| - finder.findFreeObjects(threadHeaps);
|
| - finder.findFreeObjects(centralCaches, kNumClasses, mzone->m_centralCaches);
|
| -
|
| - TCMalloc_PageHeap::PageMap* pageMap = &pageHeap->pagemap_;
|
| - PageMapFreeObjectFinder pageMapFinder(memoryReader, finder, pageHeap->entropy_);
|
| - pageMap->visitValues(pageMapFinder, memoryReader);
|
| -
|
| - PageMapMemoryUsageRecorder usageRecorder(task, context, typeMask, recorder, memoryReader, finder);
|
| - pageMap->visitValues(usageRecorder, memoryReader);
|
| - usageRecorder.recordPendingRegions();
|
| -
|
| - AdminRegionRecorder adminRegionRecorder(task, context, typeMask, recorder);
|
| - pageMap->visitAllocations(adminRegionRecorder, memoryReader);
|
| -
|
| - PageHeapAllocator<Span>* spanAllocator = memoryReader(mzone->m_spanAllocator);
|
| - PageHeapAllocator<TCMalloc_ThreadCache>* pageHeapAllocator = memoryReader(mzone->m_pageHeapAllocator);
|
| -
|
| - spanAllocator->recordAdministrativeRegions(adminRegionRecorder, memoryReader);
|
| - pageHeapAllocator->recordAdministrativeRegions(adminRegionRecorder, memoryReader);
|
| -
|
| - adminRegionRecorder.recordPendingRegions();
|
| -
|
| - return 0;
|
| -}
|
| -
|
| -size_t FastMallocZone::size(malloc_zone_t*, const void*)
|
| -{
|
| - return 0;
|
| -}
|
| -
|
| -void* FastMallocZone::zoneMalloc(malloc_zone_t*, size_t)
|
| -{
|
| - return 0;
|
| -}
|
| -
|
| -void* FastMallocZone::zoneCalloc(malloc_zone_t*, size_t, size_t)
|
| -{
|
| - return 0;
|
| -}
|
| -
|
| -void FastMallocZone::zoneFree(malloc_zone_t*, void* ptr)
|
| -{
|
| - // Due to <rdar://problem/5671357> zoneFree may be called by the system free even if the pointer
|
| - // is not in this zone. When this happens, the pointer being freed was not allocated by any
|
| - // zone so we need to print a useful error for the application developer.
|
| - malloc_printf("*** error for object %p: pointer being freed was not allocated\n", ptr);
|
| -}
|
| -
|
| -void* FastMallocZone::zoneRealloc(malloc_zone_t*, void*, size_t)
|
| -{
|
| - return 0;
|
| -}
|
| -
|
| -
|
| -#undef malloc
|
| -#undef free
|
| -#undef realloc
|
| -#undef calloc
|
| -
|
| -extern "C" {
|
| -malloc_introspection_t jscore_fastmalloc_introspection = { &FastMallocZone::enumerate, &FastMallocZone::goodSize, &FastMallocZone::check, &FastMallocZone::print,
|
| - &FastMallocZone::log, &FastMallocZone::forceLock, &FastMallocZone::forceUnlock, &FastMallocZone::statistics
|
| -
|
| -#if OS(IOS) || __MAC_OS_X_VERSION_MAX_ALLOWED >= 1060
|
| - , 0 // zone_locked will not be called on the zone unless it advertises itself as version five or higher.
|
| -#endif
|
| -#if OS(IOS) || __MAC_OS_X_VERSION_MAX_ALLOWED >= 1070
|
| - , 0, 0, 0, 0 // These members will not be used unless the zone advertises itself as version seven or higher.
|
| -#endif
|
| -
|
| - };
|
| -}
|
| -
|
| -FastMallocZone::FastMallocZone(TCMalloc_PageHeap* pageHeap, TCMalloc_ThreadCache** threadHeaps, TCMalloc_Central_FreeListPadded* centralCaches, PageHeapAllocator<Span>* spanAllocator, PageHeapAllocator<TCMalloc_ThreadCache>* pageHeapAllocator)
|
| - : m_pageHeap(pageHeap)
|
| - , m_threadHeaps(threadHeaps)
|
| - , m_centralCaches(centralCaches)
|
| - , m_spanAllocator(spanAllocator)
|
| - , m_pageHeapAllocator(pageHeapAllocator)
|
| -{
|
| - memset(&m_zone, 0, sizeof(m_zone));
|
| - m_zone.version = 4;
|
| - m_zone.zone_name = "JavaScriptCore FastMalloc";
|
| - m_zone.size = &FastMallocZone::size;
|
| - m_zone.malloc = &FastMallocZone::zoneMalloc;
|
| - m_zone.calloc = &FastMallocZone::zoneCalloc;
|
| - m_zone.realloc = &FastMallocZone::zoneRealloc;
|
| - m_zone.free = &FastMallocZone::zoneFree;
|
| - m_zone.valloc = &FastMallocZone::zoneValloc;
|
| - m_zone.destroy = &FastMallocZone::zoneDestroy;
|
| - m_zone.introspect = &jscore_fastmalloc_introspection;
|
| - malloc_zone_register(&m_zone);
|
| -}
|
| -
|
| -
|
| -void FastMallocZone::init()
|
| -{
|
| - static FastMallocZone zone(pageheap, &thread_heaps, static_cast<TCMalloc_Central_FreeListPadded*>(central_cache), &span_allocator, &threadheap_allocator);
|
| -}
|
| -
|
| -#endif // OS(DARWIN)
|
| -
|
| -} // namespace WTF
|
| -#endif // WTF_CHANGES
|
| -
|
| -#endif // FORCE_SYSTEM_MALLOC
|
|
|
Chromium Code Reviews
Issue 14238015:
Move Source/WTF/wtf to Source/wtf (Closed)
Base URL: svn://svn.chromium.org/blink/trunk