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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#define MOZ_MEMORY_IMPL
#include "mozmemory_wrap.h"
#ifdef _WIN32
# include <windows.h>
# include <io.h>
typedef intptr_t ssize_t;
#else
# include <sys/mman.h>
# include <unistd.h>
#endif
#ifdef XP_LINUX
# include <fcntl.h>
# include <stdlib.h>
#endif
#include <algorithm>
#include <cmath>
#include <cstdio>
#include <cstring>
#include "mozilla/Assertions.h"
#include "mozilla/MathAlgorithms.h"
#include "mozilla/Maybe.h"
#include "FdPrintf.h"
using namespace mozilla;
static void die(const char* message) {
/* Here, it doesn't matter that fprintf may allocate memory. */
fprintf(stderr, "%s\n", message);
exit(1);
}
#ifdef XP_LINUX
static size_t sPageSize = []() { return sysconf(_SC_PAGESIZE); }();
#endif
/* We don't want to be using malloc() to allocate our internal tracking
* data, because that would change the parameters of what is being measured,
* so we want to use data types that directly use mmap/VirtualAlloc. */
template <typename T, size_t Len>
class MappedArray {
public:
MappedArray() : mPtr(nullptr) {
#ifdef XP_LINUX
MOZ_RELEASE_ASSERT(!((sizeof(T) * Len) & (sPageSize - 1)),
"MappedArray size must be a multiple of the page size");
#endif
}
~MappedArray() {
if (mPtr) {
#ifdef _WIN32
VirtualFree(mPtr, sizeof(T) * Len, MEM_RELEASE);
#elif defined(XP_LINUX)
munmap(reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(mPtr) -
sPageSize),
sizeof(T) * Len + sPageSize * 2);
#else
munmap(mPtr, sizeof(T) * Len);
#endif
}
}
T& operator[](size_t aIndex) const {
if (mPtr) {
return mPtr[aIndex];
}
#ifdef _WIN32
mPtr = reinterpret_cast<T*>(VirtualAlloc(
nullptr, sizeof(T) * Len, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE));
if (mPtr == nullptr) {
die("VirtualAlloc error");
}
#else
size_t data_size = sizeof(T) * Len;
size_t size = data_size;
# ifdef XP_LINUX
// See below
size += sPageSize * 2;
# endif
mPtr = reinterpret_cast<T*>(mmap(nullptr, size, PROT_READ | PROT_WRITE,
MAP_ANON | MAP_PRIVATE, -1, 0));
if (mPtr == MAP_FAILED) {
die("Mmap error");
}
# ifdef XP_LINUX
// On Linux we request a page on either side of the allocation and
// mprotect them. This prevents mappings in /proc/self/smaps from being
// merged and allows us to parse this file to calculate the allocator's RSS.
MOZ_ASSERT(0 == mprotect(mPtr, sPageSize, 0));
MOZ_ASSERT(0 == mprotect(reinterpret_cast<void*>(
reinterpret_cast<uintptr_t>(mPtr) + data_size +
sPageSize),
sPageSize, 0));
mPtr = reinterpret_cast<T*>(reinterpret_cast<uintptr_t>(mPtr) + sPageSize);
# endif
#endif
return mPtr[aIndex];
}
bool ownsMapping(uintptr_t addr) const { return addr == (uintptr_t)mPtr; }
bool allocated() const { return !!mPtr; }
private:
mutable T* mPtr;
};
/* Type for records of allocations. */
struct MemSlot {
void* mPtr;
// mRequest is only valid if mPtr is non-null. It doesn't need to be cleared
// when memory is freed or realloc()ed.
size_t mRequest;
};
/* An almost infinite list of slots.
* In essence, this is a linked list of arrays of groups of slots.
* Each group is 1MB. On 64-bits, one group allows to store 64k allocations.
* Each MemSlotList instance can store 1023 such groups, which means more
* than 67M allocations. In case more would be needed, we chain to another
* MemSlotList, and so on.
* Using 1023 groups makes the MemSlotList itself page sized on 32-bits
* and 2 pages-sized on 64-bits.
*/
class MemSlotList {
static constexpr size_t kGroups = 1024 - 1;
static constexpr size_t kGroupSize = (1024 * 1024) / sizeof(MemSlot);
MappedArray<MemSlot, kGroupSize> mSlots[kGroups];
MappedArray<MemSlotList, 1> mNext;
public:
MemSlot& operator[](size_t aIndex) const {
if (aIndex < kGroupSize * kGroups) {
return mSlots[aIndex / kGroupSize][aIndex % kGroupSize];
}
aIndex -= kGroupSize * kGroups;
return mNext[0][aIndex];
}
// Ask if any of the memory-mapped buffers use this range.
bool ownsMapping(uintptr_t aStart) const {
for (const auto& slot : mSlots) {
if (slot.allocated() && slot.ownsMapping(aStart)) {
return true;
}
}
return mNext.ownsMapping(aStart) ||
(mNext.allocated() && mNext[0].ownsMapping(aStart));
}
};
/* Helper class for memory buffers */
class Buffer {
public:
Buffer() : mBuf(nullptr), mLength(0) {}
Buffer(const void* aBuf, size_t aLength)
: mBuf(reinterpret_cast<const char*>(aBuf)), mLength(aLength) {}
/* Constructor for string literals. */
template <size_t Size>
explicit Buffer(const char (&aStr)[Size]) : mBuf(aStr), mLength(Size - 1) {}
/* Returns a sub-buffer up-to but not including the given aNeedle character.
* The "parent" buffer itself is altered to begin after the aNeedle
* character.
* If the aNeedle character is not found, return the entire buffer, and empty
* the "parent" buffer. */
Buffer SplitChar(char aNeedle) {
char* buf = const_cast<char*>(mBuf);
char* c = reinterpret_cast<char*>(memchr(buf, aNeedle, mLength));
if (!c) {
return Split(mLength);
}
Buffer result = Split(c - buf);
// Remove the aNeedle character itself.
Split(1);
return result;
}
// Advance to the position after aNeedle. This is like SplitChar but does not
// return the skipped portion.
void Skip(char aNeedle, unsigned nTimes = 1) {
for (unsigned i = 0; i < nTimes; i++) {
SplitChar(aNeedle);
}
}
void SkipWhitespace() {
while (mLength > 0) {
if (!IsSpace(mBuf[0])) {
break;
}
mBuf++;
mLength--;
}
}
static bool IsSpace(char c) {
switch (c) {
case ' ':
case '\t':
case '\n':
case '\v':
case '\f':
case '\r':
return true;
}
return false;
}
/* Returns a sub-buffer of at most aLength characters. The "parent" buffer is
* amputated of those aLength characters. If the "parent" buffer is smaller
* than aLength, then its length is used instead. */
Buffer Split(size_t aLength) {
Buffer result(mBuf, std::min(aLength, mLength));
mLength -= result.mLength;
mBuf += result.mLength;
return result;
}
/* Move the buffer (including its content) to the memory address of the aOther
* buffer. */
void Slide(Buffer aOther) {
memmove(const_cast<char*>(aOther.mBuf), mBuf, mLength);
mBuf = aOther.mBuf;
}
/* Returns whether the two involved buffers have the same content. */
bool operator==(Buffer aOther) {
return mLength == aOther.mLength &&
(mBuf == aOther.mBuf || !strncmp(mBuf, aOther.mBuf, mLength));
}
bool operator!=(Buffer aOther) { return !(*this == aOther); }
/* Returns true if the buffer is not empty. */
explicit operator bool() { return mLength; }
char operator[](size_t n) const { return mBuf[n]; }
/* Returns the memory location of the buffer. */
const char* get() { return mBuf; }
/* Returns the memory location of the end of the buffer (technically, the
* first byte after the buffer). */
const char* GetEnd() { return mBuf + mLength; }
/* Extend the buffer over the content of the other buffer, assuming it is
* adjacent. */
void Extend(Buffer aOther) {
MOZ_ASSERT(aOther.mBuf == GetEnd());
mLength += aOther.mLength;
}
size_t Length() const { return mLength; }
private:
const char* mBuf;
size_t mLength;
};
/* Helper class to read from a file descriptor line by line. */
class FdReader {
public:
explicit FdReader(int aFd, bool aNeedClose = false)
: mFd(aFd),
mNeedClose(aNeedClose),
mData(&mRawBuf, 0),
mBuf(&mRawBuf, sizeof(mRawBuf)) {}
FdReader(FdReader&& aOther) noexcept
: mFd(aOther.mFd),
mNeedClose(aOther.mNeedClose),
mData(&mRawBuf, 0),
mBuf(&mRawBuf, sizeof(mRawBuf)) {
memcpy(mRawBuf, aOther.mRawBuf, sizeof(mRawBuf));
aOther.mFd = -1;
aOther.mNeedClose = false;
aOther.mData = Buffer();
aOther.mBuf = Buffer();
}
FdReader& operator=(const FdReader&) = delete;
FdReader(const FdReader&) = delete;
~FdReader() {
if (mNeedClose) {
close(mFd);
}
}
/* Read a line from the file descriptor and returns it as a Buffer instance */
Buffer ReadLine() {
while (true) {
Buffer result = mData.SplitChar('\n');
/* There are essentially three different cases here:
* - '\n' was found "early". In this case, the end of the result buffer
* is before the beginning of the mData buffer (since SplitChar
* amputated it).
* - '\n' was found as the last character of mData. In this case, mData
* is empty, but still points at the end of mBuf. result points to what
* used to be in mData, without the last character.
* - '\n' was not found. In this case too, mData is empty and points at
* the end of mBuf. But result points to the entire buffer that used to
* be pointed by mData.
* Only in the latter case do both result and mData's end match, and it's
* the only case where we need to refill the buffer.
*/
if (result.GetEnd() != mData.GetEnd()) {
return result;
}
/* Since SplitChar emptied mData, make it point to what it had before. */
mData = result;
/* And move it to the beginning of the read buffer. */
mData.Slide(mBuf);
FillBuffer();
if (!mData) {
return Buffer();
}
}
}
private:
/* Fill the read buffer. */
void FillBuffer() {
size_t size = mBuf.GetEnd() - mData.GetEnd();
Buffer remainder(mData.GetEnd(), size);
ssize_t len = 1;
while (remainder && len > 0) {
len = ::read(mFd, const_cast<char*>(remainder.get()), size);
if (len < 0) {
die("Read error");
}
size -= len;
mData.Extend(remainder.Split(len));
}
}
/* File descriptor to read from. */
int mFd;
bool mNeedClose;
/* Part of data that was read from the file descriptor but not returned with
* ReadLine yet. */
Buffer mData;
/* Buffer representation of mRawBuf */
Buffer mBuf;
/* read() buffer */
char mRawBuf[4096];
};
MOZ_BEGIN_EXTERN_C
/* Function declarations for all the replace_malloc _impl functions.
* See memory/build/replace_malloc.c */
#define MALLOC_DECL(name, return_type, ...) \
return_type name##_impl(__VA_ARGS__);
#define MALLOC_FUNCS MALLOC_FUNCS_MALLOC
#include "malloc_decls.h"
#define MALLOC_DECL(name, return_type, ...) return_type name(__VA_ARGS__);
#define MALLOC_FUNCS MALLOC_FUNCS_JEMALLOC
#include "malloc_decls.h"
#ifdef ANDROID
/* mozjemalloc and jemalloc use pthread_atfork, which Android doesn't have.
* While gecko has one in libmozglue, the replay program can't use that.
* Since we're not going to fork anyways, make it a dummy function. */
int pthread_atfork(void (*aPrepare)(void), void (*aParent)(void),
void (*aChild)(void)) {
return 0;
}
#endif
MOZ_END_EXTERN_C
template <unsigned Base = 10>
size_t parseNumber(Buffer aBuf) {
if (!aBuf) {
die("Malformed input");
}
size_t result = 0;
for (const char *c = aBuf.get(), *end = aBuf.GetEnd(); c < end; c++) {
result *= Base;
if ((*c >= '0' && *c <= '9')) {
result += *c - '0';
} else if (Base == 16 && *c >= 'a' && *c <= 'f') {
result += *c - 'a' + 10;
} else if (Base == 16 && *c >= 'A' && *c <= 'F') {
result += *c - 'A' + 10;
} else {
die("Malformed input");
}
}
return result;
}
static size_t percent(size_t a, size_t b) {
if (!b) {
return 0;
}
return size_t(round(double(a) / double(b) * 100.0));
}
class Distribution {
public:
// Default constructor used for array initialisation.
Distribution()
: mMaxSize(0),
mNextSmallest(0),
mShift(0),
mArrayOffset(0),
mArraySlots(0),
mTotalRequests(0),
mRequests{0} {}
Distribution(size_t max_size, size_t next_smallest, size_t bucket_size)
: mMaxSize(max_size),
mNextSmallest(next_smallest),
mShift(CeilingLog2(bucket_size)),
mArrayOffset(1 + next_smallest),
mArraySlots((max_size - next_smallest) >> mShift),
mTotalRequests(0),
mRequests{
0,
} {
MOZ_ASSERT(mMaxSize);
MOZ_RELEASE_ASSERT(mArraySlots <= MAX_NUM_BUCKETS);
}
Distribution& operator=(const Distribution& aOther) = default;
void addRequest(size_t request) {
MOZ_ASSERT(mMaxSize);
mRequests[(request - mArrayOffset) >> mShift]++;
mTotalRequests++;
}
void printDist(platform_handle_t std_err) {
MOZ_ASSERT(mMaxSize);
// The translation to turn a slot index into a memory request size.
const size_t array_offset_add = (1 << mShift) + mNextSmallest;
FdPrintf(std_err, "\n%zu-bin Distribution:\n", mMaxSize);
FdPrintf(std_err, " request : count percent\n");
size_t range_start = mNextSmallest + 1;
for (size_t j = 0; j < mArraySlots; j++) {
size_t range_end = (j << mShift) + array_offset_add;
FdPrintf(std_err, "%5zu - %5zu: %6zu %6zu%%\n", range_start, range_end,
mRequests[j], percent(mRequests[j], mTotalRequests));
range_start = range_end + 1;
}
}
size_t maxSize() const { return mMaxSize; }
private:
static constexpr size_t MAX_NUM_BUCKETS = 16;
// If size is zero this distribution is uninitialised.
size_t mMaxSize;
size_t mNextSmallest;
// Parameters to convert a size into a slot number.
unsigned mShift;
unsigned mArrayOffset;
// The number of slots.
unsigned mArraySlots;
size_t mTotalRequests;
size_t mRequests[MAX_NUM_BUCKETS];
};
#ifdef XP_LINUX
struct MemoryMap {
uintptr_t mStart;
uintptr_t mEnd;
bool mReadable;
bool mPrivate;
bool mAnon;
bool mIsStack;
bool mIsSpecial;
size_t mRSS;
bool IsCandidate() const {
// Candidates mappings are:
// * anonymous
// * they are private (not shared),
// * anonymous or "[heap]" (not another area such as stack),
//
// The only mappings we're falsely including are the .bss segments for
// shared libraries.
return mReadable && mPrivate && mAnon && !mIsStack && !mIsSpecial;
}
};
class SMapsReader : private FdReader {
private:
explicit SMapsReader(FdReader&& reader) : FdReader(std::move(reader)) {}
public:
static Maybe<SMapsReader> open() {
int fd = ::open(FILENAME, O_RDONLY);
if (fd < 0) {
perror(FILENAME);
return mozilla::Nothing();
}
return Some(SMapsReader(FdReader(fd, true)));
}
Maybe<MemoryMap> readMap(platform_handle_t aStdErr) {
// This is not very tolerant of format changes because things like
// parseNumber will crash if they get a bad value. TODO: make this
// soft-fail.
Buffer line = ReadLine();
if (!line) {
return Nothing();
}
// We're going to be at the start of an entry, start tokenising the first
// line.
// Range
Buffer range = line.SplitChar(' ');
uintptr_t range_start = parseNumber<16>(range.SplitChar('-'));
uintptr_t range_end = parseNumber<16>(range);
// Mode.
Buffer mode = line.SplitChar(' ');
if (mode.Length() != 4) {
FdPrintf(aStdErr, "Couldn't parse SMAPS file\n");
return Nothing();
}
bool readable = mode[0] == 'r';
bool private_ = mode[3] == 'p';
// Offset, device and inode.
line.SkipWhitespace();
bool zero_offset = !parseNumber<16>(line.SplitChar(' '));
line.SkipWhitespace();
bool no_device = line.SplitChar(' ') == Buffer("00:00");
line.SkipWhitespace();
bool zero_inode = !parseNumber(line.SplitChar(' '));
bool is_anon = zero_offset && no_device && zero_inode;
// Filename, or empty for anon mappings.
line.SkipWhitespace();
Buffer filename = line.SplitChar(' ');
bool is_stack;
bool is_special;
if (filename && filename[0] == '[') {
is_stack = filename == Buffer("[stack]");
is_special = filename == Buffer("[vdso]") ||
filename == Buffer("[vvar]") ||
filename == Buffer("[vsyscall]");
} else {
is_stack = false;
is_special = false;
}
size_t rss = 0;
while ((line = ReadLine())) {
Buffer field = line.SplitChar(':');
if (field == Buffer("VmFlags")) {
// This is the last field, at least in the current format. Break this
// loop to read the next mapping.
break;
}
if (field == Buffer("Rss")) {
line.SkipWhitespace();
Buffer value = line.SplitChar(' ');
rss = parseNumber(value) * 1024;
}
}
return Some(MemoryMap({range_start, range_end, readable, private_, is_anon,
is_stack, is_special, rss}));
}
static constexpr char FILENAME[] = "/proc/self/smaps";
};
#endif // XP_LINUX
/* Class to handle dispatching the replay function calls to replace-malloc. */
class Replay {
public:
Replay() {
#ifdef _WIN32
// See comment in FdPrintf.h as to why native win32 handles are used.
mStdErr = GetStdHandle(STD_ERROR_HANDLE);
#else
mStdErr = fileno(stderr);
#endif
#ifdef XP_LINUX
BuildInitialMapInfo();
#endif
}
void enableSlopCalculation() { mCalculateSlop = true; }
void enableMemset() { mDoMemset = true; }
MemSlot& operator[](size_t index) const { return mSlots[index]; }
void malloc(Buffer& aArgs, Buffer& aResult) {
MemSlot& aSlot = SlotForResult(aResult);
mOps++;
size_t size = parseNumber(aArgs);
aSlot.mPtr = ::malloc_impl(size);
if (aSlot.mPtr) {
aSlot.mRequest = size;
MaybeCommit(aSlot);
if (mCalculateSlop) {
mTotalRequestedSize += size;
mTotalAllocatedSize += ::malloc_usable_size_impl(aSlot.mPtr);
}
}
}
void posix_memalign(Buffer& aArgs, Buffer& aResult) {
MemSlot& aSlot = SlotForResult(aResult);
mOps++;
size_t alignment = parseNumber(aArgs.SplitChar(','));
size_t size = parseNumber(aArgs);
void* ptr;
if (::posix_memalign_impl(&ptr, alignment, size) == 0) {
aSlot.mPtr = ptr;
aSlot.mRequest = size;
MaybeCommit(aSlot);
if (mCalculateSlop) {
mTotalRequestedSize += size;
mTotalAllocatedSize += ::malloc_usable_size_impl(aSlot.mPtr);
}
} else {
aSlot.mPtr = nullptr;
}
}
void aligned_alloc(Buffer& aArgs, Buffer& aResult) {
MemSlot& aSlot = SlotForResult(aResult);
mOps++;
size_t alignment = parseNumber(aArgs.SplitChar(','));
size_t size = parseNumber(aArgs);
aSlot.mPtr = ::aligned_alloc_impl(alignment, size);
if (aSlot.mPtr) {
aSlot.mRequest = size;
MaybeCommit(aSlot);
if (mCalculateSlop) {
mTotalRequestedSize += size;
mTotalAllocatedSize += ::malloc_usable_size_impl(aSlot.mPtr);
}
}
}
void calloc(Buffer& aArgs, Buffer& aResult) {
MemSlot& aSlot = SlotForResult(aResult);
mOps++;
size_t num = parseNumber(aArgs.SplitChar(','));
size_t size = parseNumber(aArgs);
aSlot.mPtr = ::calloc_impl(num, size);
if (aSlot.mPtr) {
aSlot.mRequest = num * size;
MaybeCommit(aSlot);
if (mCalculateSlop) {
mTotalRequestedSize += num * size;
mTotalAllocatedSize += ::malloc_usable_size_impl(aSlot.mPtr);
}
}
}
void realloc(Buffer& aArgs, Buffer& aResult) {
MemSlot& aSlot = SlotForResult(aResult);
mOps++;
Buffer dummy = aArgs.SplitChar('#');
if (dummy) {
die("Malformed input");
}
size_t slot_id = parseNumber(aArgs.SplitChar(','));
size_t size = parseNumber(aArgs);
MemSlot& old_slot = (*this)[slot_id];
void* old_ptr = old_slot.mPtr;
old_slot.mPtr = nullptr;
aSlot.mPtr = ::realloc_impl(old_ptr, size);
if (aSlot.mPtr) {
aSlot.mRequest = size;
MaybeCommit(aSlot);
if (mCalculateSlop) {
mTotalRequestedSize += size;
mTotalAllocatedSize += ::malloc_usable_size_impl(aSlot.mPtr);
}
}
}
void free(Buffer& aArgs, Buffer& aResult) {
if (aResult) {
die("Malformed input");
}
mOps++;
Buffer dummy = aArgs.SplitChar('#');
if (dummy) {
die("Malformed input");
}
size_t slot_id = parseNumber(aArgs);
MemSlot& slot = (*this)[slot_id];
::free_impl(slot.mPtr);
slot.mPtr = nullptr;
}
void memalign(Buffer& aArgs, Buffer& aResult) {
MemSlot& aSlot = SlotForResult(aResult);
mOps++;
size_t alignment = parseNumber(aArgs.SplitChar(','));
size_t size = parseNumber(aArgs);
aSlot.mPtr = ::memalign_impl(alignment, size);
if (aSlot.mPtr) {
aSlot.mRequest = size;
MaybeCommit(aSlot);
if (mCalculateSlop) {
mTotalRequestedSize += size;
mTotalAllocatedSize += ::malloc_usable_size_impl(aSlot.mPtr);
}
}
}
void valloc(Buffer& aArgs, Buffer& aResult) {
MemSlot& aSlot = SlotForResult(aResult);
mOps++;
size_t size = parseNumber(aArgs);
aSlot.mPtr = ::valloc_impl(size);
if (aSlot.mPtr) {
aSlot.mRequest = size;
MaybeCommit(aSlot);
if (mCalculateSlop) {
mTotalRequestedSize += size;
mTotalAllocatedSize += ::malloc_usable_size_impl(aSlot.mPtr);
}
}
}
void jemalloc_stats(Buffer& aArgs, Buffer& aResult) {
if (aArgs || aResult) {
die("Malformed input");
}
mOps++;
jemalloc_stats_t stats;
// Using a variable length array here is a GCC & Clang extension. But it
// allows us to place this on the stack and not alter jemalloc's profiling.
const size_t num_bins = ::jemalloc_stats_num_bins();
const size_t MAX_NUM_BINS = 100;
if (num_bins > MAX_NUM_BINS) {
die("Exceeded maximum number of jemalloc stats bins");
}
jemalloc_bin_stats_t bin_stats[MAX_NUM_BINS] = {{0}};
::jemalloc_stats_internal(&stats, bin_stats);
#ifdef XP_LINUX
size_t rss = get_rss();
#endif
size_t num_objects = 0;
size_t num_sloppy_objects = 0;
size_t total_allocated = 0;
size_t total_slop = 0;
size_t large_slop = 0;
size_t large_used = 0;
size_t huge_slop = 0;
size_t huge_used = 0;
size_t bin_slop[MAX_NUM_BINS] = {0};
for (size_t slot_id = 0; slot_id < mNumUsedSlots; slot_id++) {
MemSlot& slot = mSlots[slot_id];
if (slot.mPtr) {
size_t used = ::malloc_usable_size_impl(slot.mPtr);
size_t slop = used - slot.mRequest;
total_allocated += used;
total_slop += slop;
num_objects++;
if (slop) {
num_sloppy_objects++;
}
if (used <=
(stats.subpage_max ? stats.subpage_max : stats.quantum_wide_max)) {
// We know that this is an inefficient linear search, but there's a
// small number of bins and this is simple.
for (unsigned i = 0; i < num_bins; i++) {
auto& bin = bin_stats[i];
if (used == bin.size) {
bin_slop[i] += slop;
break;
}
}
} else if (used <= stats.large_max) {
large_slop += slop;
large_used += used;
} else {
huge_slop += slop;
huge_used += used;
}
}
}
// This formula corresponds to the calculation of wasted (from committed and
// the other parameters) within jemalloc_stats()
size_t committed = stats.allocated + stats.waste + stats.pages_dirty +
stats.bookkeeping + stats.bin_unused;
FdPrintf(mStdErr, "\n");
FdPrintf(mStdErr, "Objects: %9zu\n", num_objects);
FdPrintf(mStdErr, "Slots: %9zu\n", mNumUsedSlots);
FdPrintf(mStdErr, "Ops: %9zu\n", mOps);
FdPrintf(mStdErr, "mapped: %9zu\n", stats.mapped);
FdPrintf(mStdErr, "committed: %9zu\n", committed);
#ifdef XP_LINUX
if (rss) {
FdPrintf(mStdErr, "rss: %9zu\n", rss);
}
#endif
FdPrintf(mStdErr, "allocated: %9zu\n", stats.allocated);
FdPrintf(mStdErr, "waste: %9zu\n", stats.waste);
FdPrintf(mStdErr, "dirty: %9zu\n", stats.pages_dirty);
FdPrintf(mStdErr, "fresh: %9zu\n", stats.pages_fresh);
FdPrintf(mStdErr, "madvised: %9zu\n", stats.pages_madvised);
FdPrintf(mStdErr, "bookkeep: %9zu\n", stats.bookkeeping);
FdPrintf(mStdErr, "bin-unused: %9zu\n", stats.bin_unused);
FdPrintf(mStdErr, "quantum-max: %9zu\n", stats.quantum_max);
FdPrintf(mStdErr, "quantum-wide-max: %9zu\n", stats.quantum_wide_max);
FdPrintf(mStdErr, "subpage-max: %9zu\n", stats.subpage_max);
FdPrintf(mStdErr, "large-max: %9zu\n", stats.large_max);
if (mCalculateSlop) {
size_t slop = mTotalAllocatedSize - mTotalRequestedSize;
FdPrintf(mStdErr,
"Total slop for all allocations: %zuKiB/%zuKiB (%zu%%)\n",
slop / 1024, mTotalAllocatedSize / 1024,
percent(slop, mTotalAllocatedSize));
}
FdPrintf(mStdErr, "Live sloppy objects: %zu/%zu (%zu%%)\n",
num_sloppy_objects, num_objects,
percent(num_sloppy_objects, num_objects));
FdPrintf(mStdErr, "Live sloppy bytes: %zuKiB/%zuKiB (%zu%%)\n",
total_slop / 1024, total_allocated / 1024,
percent(total_slop, total_allocated));
FdPrintf(mStdErr, "\n%8s %11s %10s %8s %9s %9s %8s\n", "bin-size",
"unused (c)", "total (c)", "used (c)", "non-full (r)", "total (r)",
"used (r)");
for (unsigned i = 0; i < num_bins; i++) {
auto& bin = bin_stats[i];
MOZ_ASSERT(bin.size);
FdPrintf(mStdErr, "%8zu %8zuKiB %7zuKiB %7zu%% %12zu %9zu %7zu%%\n",
bin.size, bin.bytes_unused / 1024, bin.bytes_total / 1024,
percent(bin.bytes_total - bin.bytes_unused, bin.bytes_total),
bin.num_non_full_runs, bin.num_runs,
percent(bin.num_runs - bin.num_non_full_runs, bin.num_runs));
}
FdPrintf(mStdErr, "\n%5s %8s %9s %7s\n", "bin", "slop", "used", "percent");
for (unsigned i = 0; i < num_bins; i++) {
auto& bin = bin_stats[i];
size_t used = bin.bytes_total - bin.bytes_unused;
FdPrintf(mStdErr, "%5zu %8zu %9zu %6zu%%\n", bin.size, bin_slop[i], used,
percent(bin_slop[i], used));
}
FdPrintf(mStdErr, "%5s %8zu %9zu %6zu%%\n", "large", large_slop, large_used,
percent(large_slop, large_used));
FdPrintf(mStdErr, "%5s %8zu %9zu %6zu%%\n", "huge", huge_slop, huge_used,
percent(huge_slop, huge_used));
print_distributions(stats, bin_stats);
}
private:
/*
* Create and print frequency distributions of memory requests.
*/
void print_distributions(jemalloc_stats_t& stats,
jemalloc_bin_stats_t* bin_stats) {
const size_t num_bins = ::jemalloc_stats_num_bins();
// We compute distributions for all of the bins for small allocations
// (num_bins) plus two more distributions for larger allocations.
Distribution dists[num_bins + 2];
unsigned last_size = 0;
unsigned num_dists = 0;
for (unsigned i = 0; i < num_bins; i++) {
auto& bin = bin_stats[i];
auto& dist = dists[num_dists++];
MOZ_ASSERT(bin.size);
if (bin.size <= 16) {
// 1 byte buckets.
dist = Distribution(bin.size, last_size, 1);
} else if (bin.size <= stats.quantum_max) {
// 4 buckets, (4 bytes per bucket with a 16 byte quantum).
dist = Distribution(bin.size, last_size, stats.quantum / 4);
} else if (bin.size <= stats.quantum_wide_max) {
// 8 buckets, (32 bytes per bucket with a 256 byte quantum-wide).
dist = Distribution(bin.size, last_size, stats.quantum_wide / 8);
} else {
// 16 buckets.
dist = Distribution(bin.size, last_size, (bin.size - last_size) / 16);
}
last_size = bin.size;
}
// 16 buckets.
dists[num_dists] = Distribution(stats.page_size, last_size,
(stats.page_size - last_size) / 16);
num_dists++;
// Buckets are 1/4 of the page size (12 buckets).
dists[num_dists] =
Distribution(stats.page_size * 4, stats.page_size, stats.page_size / 4);
num_dists++;
MOZ_RELEASE_ASSERT(num_dists <= num_bins + 2);
for (size_t slot_id = 0; slot_id < mNumUsedSlots; slot_id++) {
MemSlot& slot = mSlots[slot_id];
if (slot.mPtr) {
for (size_t i = 0; i < num_dists; i++) {
if (slot.mRequest <= dists[i].maxSize()) {
dists[i].addRequest(slot.mRequest);
break;
}
}
}
}
for (unsigned i = 0; i < num_dists; i++) {
dists[i].printDist(mStdErr);
}
}
#ifdef XP_LINUX
size_t get_rss() {
if (mGetRSSFailed) {
return 0;
}
// On Linux we can determine the RSS of the heap area by examining the
// smaps file.
mozilla::Maybe<SMapsReader> reader = SMapsReader::open();
if (!reader) {
mGetRSSFailed = true;
return 0;
}
size_t rss = 0;
while (Maybe<MemoryMap> map = reader->readMap(mStdErr)) {
if (map->IsCandidate() && !mSlots.ownsMapping(map->mStart) &&
!InitialMapsContains(map->mStart)) {
rss += map->mRSS;
}
}
return rss;
}
bool InitialMapsContains(uintptr_t aRangeStart) {
for (unsigned i = 0; i < mNumInitialMaps; i++) {
MOZ_ASSERT(i < MAX_INITIAL_MAPS);
if (mInitialMaps[i] == aRangeStart) {
return true;
}
}
return false;
}
public:
void BuildInitialMapInfo() {
if (mGetRSSFailed) {
return;
}
Maybe<SMapsReader> reader = SMapsReader::open();
if (!reader) {
mGetRSSFailed = true;
return;
}
while (Maybe<MemoryMap> map = reader->readMap(mStdErr)) {
if (map->IsCandidate()) {
if (mNumInitialMaps >= MAX_INITIAL_MAPS) {
FdPrintf(mStdErr, "Too many initial mappings, can't compute RSS\n");
mGetRSSFailed = false;
return;
}
mInitialMaps[mNumInitialMaps++] = map->mStart;
}
}
}
#endif
private:
MemSlot& SlotForResult(Buffer& aResult) {
/* Parse result value and get the corresponding slot. */
Buffer dummy = aResult.SplitChar('=');
Buffer dummy2 = aResult.SplitChar('#');
if (dummy || dummy2) {
die("Malformed input");
}
size_t slot_id = parseNumber(aResult);
mNumUsedSlots = std::max(mNumUsedSlots, slot_id + 1);
return mSlots[slot_id];
}
void MaybeCommit(MemSlot& aSlot) {
if (mDoMemset) {
// Write any byte, 0x55 isn't significant.
memset(aSlot.mPtr, 0x55, aSlot.mRequest);
}
}
platform_handle_t mStdErr;
size_t mOps = 0;
// The number of slots that have been used. It is used to iterate over slots
// without accessing those we haven't initialised.
size_t mNumUsedSlots = 0;
MemSlotList mSlots;
size_t mTotalRequestedSize = 0;
size_t mTotalAllocatedSize = 0;
// Whether to calculate slop for all allocations over the runtime of a
// process.
bool mCalculateSlop = false;
bool mDoMemset = false;
#ifdef XP_LINUX
// If we have a failure reading smaps info then this is used to disable that
// feature.
bool mGetRSSFailed = false;
// The initial memory mappings are recorded here at start up. We exclude
// memory in these mappings when computing RSS. We assume they do not grow
// and that no regions are allocated near them, this is true because they'll
// only record the .bss and .data segments from our binary and shared objects
// or regions that logalloc-replay has created for MappedArrays.
//
// 64 should be enough for anybody.
static constexpr unsigned MAX_INITIAL_MAPS = 64;
uintptr_t mInitialMaps[MAX_INITIAL_MAPS];
unsigned mNumInitialMaps = 0;
#endif // XP_LINUX
};
static Replay replay;
int main(int argc, const char* argv[]) {
size_t first_pid = 0;
FdReader reader(0);
for (int i = 1; i < argc; i++) {
const char* option = argv[i];
if (strcmp(option, "-s") == 0) {
// Do accounting to calculate allocation slop.
replay.enableSlopCalculation();
} else if (strcmp(option, "-c") == 0) {
// Touch memory as we allocate it.
replay.enableMemset();
} else {
fprintf(stderr, "Unknown command line option: %s\n", option);
return EXIT_FAILURE;
}
}
/* Read log from stdin and dispatch function calls to the Replay instance.
* The log format is essentially:
* <pid> <tid> <function>([<args>])[=<result>]
* <args> is a comma separated list of arguments.
*
* The logs are expected to be preprocessed so that allocations are
* attributed a tracking slot. The input is trusted not to have crazy
* values for these slot numbers.
*
* <result>, as well as some of the args to some of the function calls are
* such slot numbers.
*/
while (true) {
Buffer line = reader.ReadLine();
if (!line) {
break;
}
size_t pid = parseNumber(line.SplitChar(' '));
if (!first_pid) {
first_pid = pid;
}
/* The log may contain data for several processes, only entries for the
* very first that appears are treated. */
if (first_pid != pid) {
continue;
}
/* The log contains thread ids for manual analysis, but we just ignore them
* for now. */
parseNumber(line.SplitChar(' '));
Buffer func = line.SplitChar('(');
Buffer args = line.SplitChar(')');
if (func == Buffer("jemalloc_stats")) {
replay.jemalloc_stats(args, line);
} else if (func == Buffer("free")) {
replay.free(args, line);
} else if (func == Buffer("malloc")) {
replay.malloc(args, line);
} else if (func == Buffer("posix_memalign")) {
replay.posix_memalign(args, line);
} else if (func == Buffer("aligned_alloc")) {
replay.aligned_alloc(args, line);
} else if (func == Buffer("calloc")) {
replay.calloc(args, line);
} else if (func == Buffer("realloc")) {
replay.realloc(args, line);
} else if (func == Buffer("memalign")) {
replay.memalign(args, line);
} else if (func == Buffer("valloc")) {
replay.valloc(args, line);
} else {
die("Malformed input");
}
}
return 0;
}