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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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "nsTraceRefcnt.h"
#include "mozilla/Attributes.h"
#include "mozilla/AutoRestore.h"
#include "mozilla/CycleCollectedJSContext.h"
#include "mozilla/IntegerPrintfMacros.h"
#include "mozilla/Path.h"
#include "mozilla/StaticPtr.h"
#include "nsXPCOMPrivate.h"
#include "nscore.h"
#include "nsClassHashtable.h"
#include "nsContentUtils.h"
#include "nsISupports.h"
#include "nsHashKeys.h"
#include "nsPrintfCString.h"
#include "nsTArray.h"
#include "nsTHashtable.h"
#include "prenv.h"
#include "prlink.h"
#include "nsCRT.h"
#include <math.h>
#include "nsHashKeys.h"
#include "mozilla/StackWalk.h"
#include "nsThreadUtils.h"
#include "CodeAddressService.h"
#include "nsXULAppAPI.h"
#ifdef XP_WIN
# include <process.h>
# define getpid _getpid
#else
# include <unistd.h>
#endif
#include "mozilla/Atomics.h"
#include "mozilla/AutoRestore.h"
#include "mozilla/BlockingResourceBase.h"
#include "mozilla/PoisonIOInterposer.h"
#include "mozilla/UniquePtr.h"
#include <string>
#include <vector>
#ifdef HAVE_DLOPEN
# include <dlfcn.h>
#endif
#ifdef MOZ_DMD
# include "base/process_util.h"
# include "nsMemoryInfoDumper.h"
#endif
// dynamic_cast<void*> is not supported on Windows without RTTI.
#ifndef _WIN32
# define HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR
#endif
////////////////////////////////////////////////////////////////////////////////
#include "prthread.h"
// We use a spin lock instead of a regular mutex because this lock is usually
// only held for a very short time, and gets grabbed at a very high frequency
// (~100000 times per second). On Mac, the overhead of using a regular lock
// is very high, see bug 1137963.
static mozilla::Atomic<uintptr_t, mozilla::ReleaseAcquire> gTraceLogLocked;
struct MOZ_STACK_CLASS AutoTraceLogLock final {
bool doRelease;
AutoTraceLogLock() : doRelease(true) {
uintptr_t currentThread =
reinterpret_cast<uintptr_t>(PR_GetCurrentThread());
if (gTraceLogLocked == currentThread) {
doRelease = false;
} else {
while (!gTraceLogLocked.compareExchange(0, currentThread)) {
PR_Sleep(PR_INTERVAL_NO_WAIT); /* yield */
}
}
}
~AutoTraceLogLock() {
if (doRelease) gTraceLogLocked = 0;
}
};
class BloatEntry;
struct SerialNumberRecord;
using mozilla::AutoRestore;
using mozilla::CodeAddressService;
using mozilla::CycleCollectedJSContext;
using mozilla::StaticAutoPtr;
using BloatHash = nsClassHashtable<nsDepCharHashKey, BloatEntry>;
using CharPtrSet = nsTHashtable<nsCharPtrHashKey>;
using IntPtrSet = nsTHashtable<IntPtrHashKey>;
using SerialHash = nsClassHashtable<nsVoidPtrHashKey, SerialNumberRecord>;
static StaticAutoPtr<BloatHash> gBloatView;
static StaticAutoPtr<CharPtrSet> gTypesToLog;
static StaticAutoPtr<IntPtrSet> gObjectsToLog;
static StaticAutoPtr<SerialHash> gSerialNumbers;
static intptr_t gNextSerialNumber;
static bool gDumpedStatistics = false;
static bool gLogJSStacks = false;
// By default, debug builds only do bloat logging. Bloat logging
// only tries to record when an object is created or destroyed, so we
// optimize the common case in NS_LogAddRef and NS_LogRelease where
// only bloat logging is enabled and no logging needs to be done.
enum LoggingType { NoLogging, OnlyBloatLogging, FullLogging };
static LoggingType gLogging;
static bool gLogLeaksOnly;
#define BAD_TLS_INDEX ((unsigned)-1)
// if gActivityTLS == BAD_TLS_INDEX, then we're
// unitialized... otherwise this points to a NSPR TLS thread index
// indicating whether addref activity is legal. If the PTR_TO_INT32 is 0 then
// activity is ok, otherwise not!
static unsigned gActivityTLS = BAD_TLS_INDEX;
static bool gInitialized;
static nsrefcnt gInitCount;
static FILE* gBloatLog = nullptr;
static FILE* gRefcntsLog = nullptr;
static FILE* gAllocLog = nullptr;
static FILE* gCOMPtrLog = nullptr;
static void WalkTheStackSavingLocations(std::vector<void*>& aLocations,
const void* aFirstFramePC);
struct SerialNumberRecord {
SerialNumberRecord()
: serialNumber(++gNextSerialNumber), refCount(0), COMPtrCount(0) {}
intptr_t serialNumber;
int32_t refCount;
int32_t COMPtrCount;
// We use std:: classes here rather than the XPCOM equivalents because the
// XPCOM equivalents do leak-checking, and if you try to leak-check while
// leak-checking, you're gonna have a bad time.
std::vector<void*> allocationStack;
mozilla::UniquePtr<char[]> jsStack;
void SaveJSStack() {
// If this thread isn't running JS, there's nothing to do.
if (!CycleCollectedJSContext::Get()) {
return;
}
if (!nsContentUtils::IsInitialized()) {
return;
}
JSContext* cx = nsContentUtils::GetCurrentJSContext();
if (!cx) {
return;
}
JS::UniqueChars chars = xpc_PrintJSStack(cx,
/*showArgs=*/false,
/*showLocals=*/false,
/*showThisProps=*/false);
size_t len = strlen(chars.get());
jsStack = mozilla::MakeUnique<char[]>(len + 1);
memcpy(jsStack.get(), chars.get(), len + 1);
}
};
struct nsTraceRefcntStats {
uint64_t mCreates;
uint64_t mDestroys;
bool HaveLeaks() const { return mCreates != mDestroys; }
void Clear() {
mCreates = 0;
mDestroys = 0;
}
int64_t NumLeaked() const { return (int64_t)(mCreates - mDestroys); }
};
#ifdef DEBUG
static const char kStaticCtorDtorWarning[] =
"XPCOM objects created/destroyed from static ctor/dtor";
static void AssertActivityIsLegal() {
if (gActivityTLS == BAD_TLS_INDEX || PR_GetThreadPrivate(gActivityTLS)) {
if (PR_GetEnv("MOZ_FATAL_STATIC_XPCOM_CTORS_DTORS")) {
MOZ_CRASH_UNSAFE(kStaticCtorDtorWarning);
} else {
NS_WARNING(kStaticCtorDtorWarning);
}
}
}
# define ASSERT_ACTIVITY_IS_LEGAL \
do { \
AssertActivityIsLegal(); \
} while (0)
#else
# define ASSERT_ACTIVITY_IS_LEGAL \
do { \
} while (0)
#endif // DEBUG
////////////////////////////////////////////////////////////////////////////////
mozilla::StaticAutoPtr<CodeAddressService<>> gCodeAddressService;
////////////////////////////////////////////////////////////////////////////////
class BloatEntry {
public:
BloatEntry(const char* aClassName, uint32_t aClassSize)
: mClassSize(aClassSize), mStats() {
MOZ_ASSERT(strlen(aClassName) > 0, "BloatEntry name must be non-empty");
mClassName = aClassName;
mStats.Clear();
mTotalLeaked = 0;
}
~BloatEntry() = default;
uint32_t GetClassSize() { return (uint32_t)mClassSize; }
const char* GetClassName() { return mClassName; }
void Ctor() { mStats.mCreates++; }
void Dtor() { mStats.mDestroys++; }
void Total(BloatEntry* aTotal) {
aTotal->mStats.mCreates += mStats.mCreates;
aTotal->mStats.mDestroys += mStats.mDestroys;
aTotal->mClassSize +=
mClassSize * mStats.mCreates; // adjust for average in DumpTotal
aTotal->mTotalLeaked += mClassSize * mStats.NumLeaked();
}
void DumpTotal(FILE* aOut) {
mClassSize /= mStats.mCreates;
Dump(-1, aOut);
}
bool PrintDumpHeader(FILE* aOut, const char* aMsg) {
fprintf(aOut, "\n== BloatView: %s, %s process %d\n", aMsg,
XRE_GetProcessTypeString(), getpid());
if (gLogLeaksOnly && !mStats.HaveLeaks()) {
return false;
}
// clang-format off
fprintf(aOut,
"\n" \
" |<----------------Class--------------->|<-----Bytes------>|<----Objects---->|\n" \
" | | Per-Inst Leaked| Total Rem|\n");
// clang-format on
this->DumpTotal(aOut);
return true;
}
void Dump(int aIndex, FILE* aOut) {
if (gLogLeaksOnly && !mStats.HaveLeaks()) {
return;
}
if (mStats.HaveLeaks() || mStats.mCreates != 0) {
fprintf(aOut,
"%4d |%-38.38s| %8d %8" PRId64 "|%8" PRIu64 " %8" PRId64 "|\n",
aIndex + 1, mClassName, GetClassSize(),
nsCRT::strcmp(mClassName, "TOTAL")
? (mStats.NumLeaked() * GetClassSize())
: mTotalLeaked,
mStats.mCreates, mStats.NumLeaked());
}
}
protected:
const char* mClassName;
// mClassSize is stored as a double because of the way we compute the avg
// class size for total bloat.
double mClassSize;
// mTotalLeaked is only used for the TOTAL entry.
int64_t mTotalLeaked;
nsTraceRefcntStats mStats;
};
static void EnsureBloatView() {
if (!gBloatView) {
gBloatView = new BloatHash(256);
}
}
static BloatEntry* GetBloatEntry(const char* aTypeName,
uint32_t aInstanceSize) {
EnsureBloatView();
BloatEntry* entry = gBloatView->Get(aTypeName);
if (!entry && aInstanceSize > 0) {
entry = gBloatView
->InsertOrUpdate(
aTypeName, MakeUnique<BloatEntry>(aTypeName, aInstanceSize))
.get();
} else {
MOZ_ASSERT(
aInstanceSize == 0 || entry->GetClassSize() == aInstanceSize,
"Mismatched sizes were recorded in the memory leak logging table. "
"The usual cause of this is having a templated class that uses "
"MOZ_COUNT_{C,D}TOR in the constructor or destructor, respectively. "
"As a workaround, the MOZ_COUNT_{C,D}TOR calls can be moved to a "
"non-templated base class. Another possible cause is a runnable with "
"an mName that matches another refcounted class, or two refcounted "
"classes with the same class name in different C++ namespaces.");
}
return entry;
}
static void DumpSerialNumbers(const SerialHash::ConstIterator& aHashEntry,
FILE* aFd, bool aDumpAsStringBuffer) {
SerialNumberRecord* record = aHashEntry.UserData();
auto* outputFile = aFd;
#ifdef HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR
fprintf(outputFile, "%" PRIdPTR " @%p (%d references; %d from COMPtrs)\n",
record->serialNumber, aHashEntry.Key(), record->refCount,
record->COMPtrCount);
#else
fprintf(outputFile, "%" PRIdPTR " @%p (%d references)\n",
record->serialNumber, aHashEntry.Key(), record->refCount);
#endif
if (aDumpAsStringBuffer) {
// This output will be wrong if the nsStringBuffer was used to
// store a char16_t string.
auto* buffer = static_cast<const nsStringBuffer*>(aHashEntry.Key());
nsDependentCString bufferString(static_cast<char*>(buffer->Data()));
fprintf(outputFile,
"Contents of leaked nsStringBuffer with storage size %d as a "
"char*: %s\n",
buffer->StorageSize(), bufferString.get());
}
if (!record->allocationStack.empty()) {
static const size_t bufLen = 1024;
char buf[bufLen];
fprintf(outputFile, "allocation stack:\n");
for (size_t i = 0, length = record->allocationStack.size(); i < length;
++i) {
gCodeAddressService->GetLocation(i, record->allocationStack[i], buf,
bufLen);
fprintf(outputFile, "%s\n", buf);
}
}
if (gLogJSStacks) {
if (record->jsStack) {
fprintf(outputFile, "JS allocation stack:\n%s\n", record->jsStack.get());
} else {
fprintf(outputFile, "There is no JS context on the stack.\n");
}
}
}
template <>
class nsDefaultComparator<BloatEntry*, BloatEntry*> {
public:
bool Equals(BloatEntry* const& aEntry1, BloatEntry* const& aEntry2) const {
return strcmp(aEntry1->GetClassName(), aEntry2->GetClassName()) == 0;
}
bool LessThan(BloatEntry* const& aEntry1, BloatEntry* const& aEntry2) const {
return strcmp(aEntry1->GetClassName(), aEntry2->GetClassName()) < 0;
}
};
nsresult nsTraceRefcnt::DumpStatistics() {
if (!gBloatLog || !gBloatView) {
return NS_ERROR_FAILURE;
}
AutoTraceLogLock lock;
MOZ_ASSERT(!gDumpedStatistics,
"Calling DumpStatistics more than once may result in "
"bogus positive or negative leaks being reported");
gDumpedStatistics = true;
// Don't try to log while we hold the lock, we'd deadlock.
AutoRestore<LoggingType> saveLogging(gLogging);
gLogging = NoLogging;
BloatEntry total("TOTAL", 0);
for (const auto& data : gBloatView->Values()) {
if (nsCRT::strcmp(data->GetClassName(), "TOTAL") != 0) {
data->Total(&total);
}
}
const char* msg;
if (gLogLeaksOnly) {
msg = "ALL (cumulative) LEAK STATISTICS";
} else {
msg = "ALL (cumulative) LEAK AND BLOAT STATISTICS";
}
const bool leaked = total.PrintDumpHeader(gBloatLog, msg);
nsTArray<BloatEntry*> entries(gBloatView->Count());
for (const auto& data : gBloatView->Values()) {
entries.AppendElement(data.get());
}
const uint32_t count = entries.Length();
if (!gLogLeaksOnly || leaked) {
// Sort the entries alphabetically by classname.
entries.Sort();
for (uint32_t i = 0; i < count; ++i) {
BloatEntry* entry = entries[i];
entry->Dump(i, gBloatLog);
}
fprintf(gBloatLog, "\n");
}
fprintf(gBloatLog, "nsTraceRefcnt::DumpStatistics: %d entries\n", count);
if (gSerialNumbers) {
bool onlyLoggingStringBuffers = gTypesToLog && gTypesToLog->Count() == 1 &&
gTypesToLog->Contains("nsStringBuffer");
fprintf(gBloatLog, "\nSerial Numbers of Leaked Objects:\n");
for (auto iter = gSerialNumbers->ConstIter(); !iter.Done(); iter.Next()) {
DumpSerialNumbers(iter, gBloatLog, onlyLoggingStringBuffers);
}
}
return NS_OK;
}
void nsTraceRefcnt::ResetStatistics() {
AutoTraceLogLock lock;
gBloatView = nullptr;
}
static intptr_t GetSerialNumber(void* aPtr, bool aCreate, void* aFirstFramePC) {
if (!aCreate) {
auto record = gSerialNumbers->Get(aPtr);
return record ? record->serialNumber : 0;
}
gSerialNumbers->WithEntryHandle(aPtr, [aFirstFramePC](auto&& entry) {
if (entry) {
MOZ_CRASH(
"If an object already has a serial number, we should be destroying "
"it.");
}
auto& record = entry.Insert(MakeUnique<SerialNumberRecord>());
WalkTheStackSavingLocations(record->allocationStack, aFirstFramePC);
if (gLogJSStacks) {
record->SaveJSStack();
}
});
return gNextSerialNumber;
}
static void RecycleSerialNumberPtr(void* aPtr) { gSerialNumbers->Remove(aPtr); }
static bool LogThisObj(intptr_t aSerialNumber) {
return gObjectsToLog->Contains(aSerialNumber);
}
using EnvCharType = mozilla::filesystem::Path::value_type;
static bool InitLog(const EnvCharType* aEnvVar, const char* aMsg,
FILE** aResult, const char* aProcType) {
#ifdef XP_WIN
// This is gross, I know.
const wchar_t* envvar = reinterpret_cast<const wchar_t*>(aEnvVar);
const char16_t* value = reinterpret_cast<const char16_t*>(::_wgetenv(envvar));
# define ENVVAR_PRINTF "%S"
#else
const char* envvar = aEnvVar;
const char* value = ::getenv(aEnvVar);
# define ENVVAR_PRINTF "%s"
#endif
if (value) {
nsTDependentString<EnvCharType> fname(value);
if (fname.EqualsLiteral("1")) {
*aResult = stdout;
fprintf(stdout, "### " ENVVAR_PRINTF " defined -- logging %s to stdout\n",
envvar, aMsg);
return true;
}
if (fname.EqualsLiteral("2")) {
*aResult = stderr;
fprintf(stdout, "### " ENVVAR_PRINTF " defined -- logging %s to stderr\n",
envvar, aMsg);
return true;
}
if (!XRE_IsParentProcess()) {
bool hasLogExtension =
fname.RFind(".log", true, -1, 4) == kNotFound ? false : true;
if (hasLogExtension) {
fname.Cut(fname.Length() - 4, 4);
}
fname.Append('_');
fname.AppendASCII(aProcType);
fname.AppendLiteral("_pid");
fname.AppendInt((uint32_t)getpid());
if (hasLogExtension) {
fname.AppendLiteral(".log");
}
}
#ifdef XP_WIN
FILE* stream = ::_wfopen(fname.get(), L"wN");
const wchar_t* fp = (const wchar_t*)fname.get();
#else
FILE* stream = ::fopen(fname.get(), "w");
const char* fp = fname.get();
#endif
if (stream) {
MozillaRegisterDebugFD(fileno(stream));
#ifdef MOZ_ENABLE_FORKSERVER
base::RegisterForkServerNoCloseFD(fileno(stream));
#endif
*aResult = stream;
fprintf(stderr,
"### " ENVVAR_PRINTF " defined -- logging %s to " ENVVAR_PRINTF
"\n",
envvar, aMsg, fp);
return true;
}
fprintf(stderr,
"### " ENVVAR_PRINTF
" defined -- unable to log %s to " ENVVAR_PRINTF "\n",
envvar, aMsg, fp);
MOZ_ASSERT(false, "Tried and failed to create an XPCOM log");
#undef ENVVAR_PRINTF
}
return false;
}
static void maybeUnregisterAndCloseFile(FILE*& aFile) {
if (!aFile) {
return;
}
MozillaUnRegisterDebugFILE(aFile);
fclose(aFile);
aFile = nullptr;
}
static void DoInitTraceLog(const char* aProcType) {
#ifdef XP_WIN
# define ENVVAR(x) u"" x
#else
# define ENVVAR(x) x
#endif
bool defined = InitLog(ENVVAR("XPCOM_MEM_BLOAT_LOG"), "bloat/leaks",
&gBloatLog, aProcType);
if (!defined) {
gLogLeaksOnly =
InitLog(ENVVAR("XPCOM_MEM_LEAK_LOG"), "leaks", &gBloatLog, aProcType);
}
if (defined || gLogLeaksOnly) {
// Use the same bloat view, if there is one, to keep it consistent
// between the fork server and content processes.
EnsureBloatView();
} else if (gBloatView) {
nsTraceRefcnt::ResetStatistics();
}
InitLog(ENVVAR("XPCOM_MEM_REFCNT_LOG"), "refcounts", &gRefcntsLog, aProcType);
InitLog(ENVVAR("XPCOM_MEM_ALLOC_LOG"), "new/delete", &gAllocLog, aProcType);
const char* classes = getenv("XPCOM_MEM_LOG_CLASSES");
#ifdef HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR
if (classes) {
InitLog(ENVVAR("XPCOM_MEM_COMPTR_LOG"), "nsCOMPtr", &gCOMPtrLog, aProcType);
} else {
if (getenv("XPCOM_MEM_COMPTR_LOG")) {
fprintf(stdout,
"### XPCOM_MEM_COMPTR_LOG defined -- "
"but XPCOM_MEM_LOG_CLASSES is not defined\n");
}
}
#else
const char* comptr_log = getenv("XPCOM_MEM_COMPTR_LOG");
if (comptr_log) {
fprintf(stdout,
"### XPCOM_MEM_COMPTR_LOG defined -- "
"but it will not work without dynamic_cast\n");
}
#endif // HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR
#undef ENVVAR
if (classes) {
// if XPCOM_MEM_LOG_CLASSES was set to some value, the value is interpreted
// as a list of class names to track
//
// Use the same |gTypesToLog| and |gSerialNumbers| to keep them
// consistent through the fork server and content processes.
// Without this, counters will be incorrect.
if (!gTypesToLog) {
gTypesToLog = new CharPtrSet(256);
}
fprintf(stdout,
"### XPCOM_MEM_LOG_CLASSES defined -- "
"only logging these classes: ");
const char* cp = classes;
for (;;) {
char* cm = (char*)strchr(cp, ',');
if (cm) {
*cm = '\0';
}
if (!gTypesToLog->Contains(cp)) {
gTypesToLog->PutEntry(cp);
}
fprintf(stdout, "%s ", cp);
if (!cm) {
break;
}
*cm = ',';
cp = cm + 1;
}
fprintf(stdout, "\n");
if (!gSerialNumbers) {
gSerialNumbers = new SerialHash(256);
}
} else {
gTypesToLog = nullptr;
gSerialNumbers = nullptr;
}
const char* objects = getenv("XPCOM_MEM_LOG_OBJECTS");
if (objects) {
gObjectsToLog = new IntPtrSet(256);
if (!(gRefcntsLog || gAllocLog || gCOMPtrLog)) {
fprintf(stdout,
"### XPCOM_MEM_LOG_OBJECTS defined -- "
"but none of XPCOM_MEM_(REFCNT|ALLOC|COMPTR)_LOG is defined\n");
} else {
fprintf(stdout,
"### XPCOM_MEM_LOG_OBJECTS defined -- "
"only logging these objects: ");
const char* cp = objects;
for (;;) {
char* cm = (char*)strchr(cp, ',');
if (cm) {
*cm = '\0';
}
intptr_t top = 0;
intptr_t bottom = 0;
while (*cp) {
if (*cp == '-') {
bottom = top;
top = 0;
++cp;
}
top *= 10;
top += *cp - '0';
++cp;
}
if (!bottom) {
bottom = top;
}
for (intptr_t serialno = bottom; serialno <= top; serialno++) {
gObjectsToLog->PutEntry(serialno);
fprintf(stdout, "%" PRIdPTR " ", serialno);
}
if (!cm) {
break;
}
*cm = ',';
cp = cm + 1;
}
fprintf(stdout, "\n");
}
}
if (getenv("XPCOM_MEM_LOG_JS_STACK")) {
fprintf(stdout, "### XPCOM_MEM_LOG_JS_STACK defined\n");
gLogJSStacks = true;
}
if (gBloatLog) {
gLogging = OnlyBloatLogging;
}
if (gRefcntsLog || gAllocLog || gCOMPtrLog) {
gLogging = FullLogging;
}
}
static void InitTraceLog() {
if (gInitialized) {
return;
}
gInitialized = true;
DoInitTraceLog(XRE_GetProcessTypeString());
}
extern "C" {
static void EnsureWrite(FILE* aStream, const char* aBuf, size_t aLen) {
#ifdef XP_WIN
int fd = _fileno(aStream);
#else
int fd = fileno(aStream);
#endif
while (aLen > 0) {
#ifdef XP_WIN
auto written = _write(fd, aBuf, aLen);
#else
auto written = write(fd, aBuf, aLen);
#endif
if (written <= 0 || size_t(written) > aLen) {
break;
}
aBuf += written;
aLen -= written;
}
}
static void PrintStackFrameCached(uint32_t aFrameNumber, void* aPC, void* aSP,
void* aClosure) {
auto stream = static_cast<FILE*>(aClosure);
static const int buflen = 1024;
char buf[buflen + 5] = " "; // 5 for leading " " and trailing '\n'
int len =
gCodeAddressService->GetLocation(aFrameNumber, aPC, buf + 4, buflen);
len = std::min(len, buflen + 1 - 2) + 4;
buf[len++] = '\n';
buf[len] = '\0';
fflush(stream);
EnsureWrite(stream, buf, len);
}
static void RecordStackFrame(uint32_t /*aFrameNumber*/, void* aPC,
void* /*aSP*/, void* aClosure) {
auto locations = static_cast<std::vector<void*>*>(aClosure);
locations->push_back(aPC);
}
}
/**
* This is a variant of |MozWalkTheStack| that uses |CodeAddressService| to
* cache the results of |NS_DescribeCodeAddress|. If |WalkTheStackCached| is
* being called frequently, it will be a few orders of magnitude faster than
* |MozWalkTheStack|. However, the cache uses a lot of memory, which can cause
* OOM crashes. Therefore, this should only be used for things like refcount
* logging which walk the stack extremely frequently.
*/
static void WalkTheStackCached(FILE* aStream, const void* aFirstFramePC) {
if (!gCodeAddressService) {
gCodeAddressService = new CodeAddressService<>();
}
MozStackWalk(PrintStackFrameCached, aFirstFramePC, /* maxFrames */ 0,
aStream);
}
static void WalkTheStackSavingLocations(std::vector<void*>& aLocations,
const void* aFirstFramePC) {
if (!gCodeAddressService) {
gCodeAddressService = new CodeAddressService<>();
}
MozStackWalk(RecordStackFrame, aFirstFramePC, /* maxFrames */ 0, &aLocations);
}
//----------------------------------------------------------------------
EXPORT_XPCOM_API(void)
NS_LogInit() {
NS_SetMainThread();
// FIXME: This is called multiple times, we should probably not allow that.
if (++gInitCount) {
nsTraceRefcnt::SetActivityIsLegal(true);
}
}
EXPORT_XPCOM_API(void)
NS_LogTerm() { mozilla::LogTerm(); }
#ifdef MOZ_DMD
// If MOZ_DMD_SHUTDOWN_LOG is set, dump a DMD report to a file.
// The value of this environment variable is used as the prefix
// of the file name, so you probably want something like "/tmp/".
// By default, this is run in all processes, but you can record a
// log only for a specific process type by setting MOZ_DMD_LOG_PROCESS
// to the process type you want to log, such as "default" or "tab".
// This method can't use the higher level XPCOM file utilities
// because it is run very late in shutdown to avoid recording
// information about refcount logging entries.
static void LogDMDFile() {
const char* dmdFilePrefix = PR_GetEnv("MOZ_DMD_SHUTDOWN_LOG");
if (!dmdFilePrefix) {
return;
}
const char* logProcessEnv = PR_GetEnv("MOZ_DMD_LOG_PROCESS");
if (logProcessEnv && !!strcmp(logProcessEnv, XRE_GetProcessTypeString())) {
return;
}
nsPrintfCString fileName("%sdmd-%d.log.gz", dmdFilePrefix,
base::GetCurrentProcId());
FILE* logFile = fopen(fileName.get(), "w");
if (NS_WARN_IF(!logFile)) {
return;
}
nsMemoryInfoDumper::DumpDMDToFile(logFile);
}
#endif // MOZ_DMD
namespace mozilla {
void LogTerm() {
NS_ASSERTION(gInitCount > 0, "NS_LogTerm without matching NS_LogInit");
if (--gInitCount == 0) {
#ifdef DEBUG
/* FIXME bug 491977: This is only going to operate on the
* BlockingResourceBase which is compiled into
* libxul/libxpcom_core.so. Anyone using external linkage will
* have their own copy of BlockingResourceBase statics which will
* not be freed by this method.
*
* It sounds like what we really want is to be able to register a
* callback function to call at XPCOM shutdown. Note that with
* this solution, however, we need to guarantee that
* BlockingResourceBase::Shutdown() runs after all other shutdown
* functions.
*/
BlockingResourceBase::Shutdown();
#endif
if (gInitialized) {
nsTraceRefcnt::DumpStatistics();
nsTraceRefcnt::ResetStatistics();
}
nsTraceRefcnt::Shutdown();
nsTraceRefcnt::SetActivityIsLegal(false);
gActivityTLS = BAD_TLS_INDEX;
#ifdef MOZ_DMD
LogDMDFile();
#endif
}
}
} // namespace mozilla
EXPORT_XPCOM_API(MOZ_NEVER_INLINE void)
NS_LogAddRef(void* aPtr, nsrefcnt aRefcnt, const char* aClass,
uint32_t aClassSize) {
ASSERT_ACTIVITY_IS_LEGAL;
if (!gInitialized) {
InitTraceLog();
}
if (gLogging == NoLogging) {
return;
}
if (aRefcnt == 1 || gLogging == FullLogging) {
AutoTraceLogLock lock;
if (aRefcnt == 1 && gBloatLog) {
BloatEntry* entry = GetBloatEntry(aClass, aClassSize);
if (entry) {
entry->Ctor();
}
}
// Here's the case where MOZ_COUNT_CTOR was not used,
// yet we still want to see creation information:
bool loggingThisType = (!gTypesToLog || gTypesToLog->Contains(aClass));
intptr_t serialno = 0;
if (gSerialNumbers && loggingThisType) {
serialno = GetSerialNumber(aPtr, aRefcnt == 1, CallerPC());
MOZ_ASSERT(serialno != 0,
"Serial number requested for unrecognized pointer! "
"Are you memmoving a refcounted object?");
auto record = gSerialNumbers->Get(aPtr);
if (record) {
++record->refCount;
}
}
bool loggingThisObject = (!gObjectsToLog || LogThisObj(serialno));
if (aRefcnt == 1 && gAllocLog && loggingThisType && loggingThisObject) {
fprintf(gAllocLog, "\n<%s> %p %" PRIdPTR " Create [thread %p]\n", aClass,
aPtr, serialno, PR_GetCurrentThread());
WalkTheStackCached(gAllocLog, CallerPC());
}
if (gRefcntsLog && loggingThisType && loggingThisObject) {
// Can't use MOZ_LOG(), b/c it truncates the line
fprintf(gRefcntsLog,
"\n<%s> %p %" PRIuPTR " AddRef %" PRIuPTR " [thread %p]\n",
aClass, aPtr, serialno, aRefcnt, PR_GetCurrentThread());
WalkTheStackCached(gRefcntsLog, CallerPC());
fflush(gRefcntsLog);
}
}
}
EXPORT_XPCOM_API(MOZ_NEVER_INLINE void)
NS_LogRelease(void* aPtr, nsrefcnt aRefcnt, const char* aClass) {
ASSERT_ACTIVITY_IS_LEGAL;
if (!gInitialized) {
InitTraceLog();
}
if (gLogging == NoLogging) {
return;
}
if (aRefcnt == 0 || gLogging == FullLogging) {
AutoTraceLogLock lock;
if (aRefcnt == 0 && gBloatLog) {
BloatEntry* entry = GetBloatEntry(aClass, 0);
if (entry) {
entry->Dtor();
}
}
bool loggingThisType = (!gTypesToLog || gTypesToLog->Contains(aClass));
intptr_t serialno = 0;
if (gSerialNumbers && loggingThisType) {
serialno = GetSerialNumber(aPtr, false, CallerPC());
MOZ_ASSERT(serialno != 0,
"Serial number requested for unrecognized pointer! "
"Are you memmoving a refcounted object?");
auto record = gSerialNumbers->Get(aPtr);
if (record) {
--record->refCount;
}
}
bool loggingThisObject = (!gObjectsToLog || LogThisObj(serialno));
if (gRefcntsLog && loggingThisType && loggingThisObject) {
// Can't use MOZ_LOG(), b/c it truncates the line
fprintf(gRefcntsLog,
"\n<%s> %p %" PRIuPTR " Release %" PRIuPTR " [thread %p]\n",
aClass, aPtr, serialno, aRefcnt, PR_GetCurrentThread());
WalkTheStackCached(gRefcntsLog, CallerPC());
fflush(gRefcntsLog);
}
// Here's the case where MOZ_COUNT_DTOR was not used,
// yet we still want to see deletion information:
if (aRefcnt == 0 && gAllocLog && loggingThisType && loggingThisObject) {
fprintf(gAllocLog, "\n<%s> %p %" PRIdPTR " Destroy [thread %p]\n", aClass,
aPtr, serialno, PR_GetCurrentThread());
WalkTheStackCached(gAllocLog, CallerPC());
}
if (aRefcnt == 0 && gSerialNumbers && loggingThisType) {
RecycleSerialNumberPtr(aPtr);
}
}
}
EXPORT_XPCOM_API(MOZ_NEVER_INLINE void)
NS_LogCtor(void* aPtr, const char* aType, uint32_t aInstanceSize) {
ASSERT_ACTIVITY_IS_LEGAL;
if (!gInitialized) {
InitTraceLog();
}
if (gLogging == NoLogging) {
return;
}
AutoTraceLogLock lock;
if (gBloatLog) {
BloatEntry* entry = GetBloatEntry(aType, aInstanceSize);
if (entry) {
entry->Ctor();
}
}
bool loggingThisType = (!gTypesToLog || gTypesToLog->Contains(aType));
intptr_t serialno = 0;
if (gSerialNumbers && loggingThisType) {
serialno = GetSerialNumber(aPtr, true, CallerPC());
MOZ_ASSERT(serialno != 0,
"GetSerialNumber should never return 0 when passed true");
}
bool loggingThisObject = (!gObjectsToLog || LogThisObj(serialno));
if (gAllocLog && loggingThisType && loggingThisObject) {
fprintf(gAllocLog, "\n<%s> %p %" PRIdPTR " Ctor (%d)\n", aType, aPtr,
serialno, aInstanceSize);
WalkTheStackCached(gAllocLog, CallerPC());
}
}
EXPORT_XPCOM_API(MOZ_NEVER_INLINE void)
NS_LogDtor(void* aPtr, const char* aType, uint32_t aInstanceSize) {
ASSERT_ACTIVITY_IS_LEGAL;
if (!gInitialized) {
InitTraceLog();
}
if (gLogging == NoLogging) {
return;
}
AutoTraceLogLock lock;
if (gBloatLog) {
BloatEntry* entry = GetBloatEntry(aType, aInstanceSize);
if (entry) {
entry->Dtor();
}
}
bool loggingThisType = (!gTypesToLog || gTypesToLog->Contains(aType));
intptr_t serialno = 0;
if (gSerialNumbers && loggingThisType) {
serialno = GetSerialNumber(aPtr, false, CallerPC());
MOZ_ASSERT(serialno != 0,
"Serial number requested for unrecognized pointer! "
"Are you memmoving a MOZ_COUNT_CTOR-tracked object?");
RecycleSerialNumberPtr(aPtr);
}
bool loggingThisObject = (!gObjectsToLog || LogThisObj(serialno));
// (If we're on a losing architecture, don't do this because we'll be
// using LogDeleteXPCOM instead to get file and line numbers.)
if (gAllocLog && loggingThisType && loggingThisObject) {
fprintf(gAllocLog, "\n<%s> %p %" PRIdPTR " Dtor (%d)\n", aType, aPtr,
serialno, aInstanceSize);
WalkTheStackCached(gAllocLog, CallerPC());
}
}
EXPORT_XPCOM_API(MOZ_NEVER_INLINE void)
NS_LogCOMPtrAddRef(void* aCOMPtr, nsISupports* aObject) {
#ifdef HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR
// Get the most-derived object.
void* object = dynamic_cast<void*>(aObject);
// This is a very indirect way of finding out what the class is
// of the object being logged. If we're logging a specific type,
// then
if (!gTypesToLog || !gSerialNumbers) {
return;
}
if (!gInitialized) {
InitTraceLog();
}
if (gLogging == FullLogging) {
AutoTraceLogLock lock;
intptr_t serialno = GetSerialNumber(object, false, CallerPC());
if (serialno == 0) {
return;
}
auto record = gSerialNumbers->Get(object);
int32_t count = record ? ++record->COMPtrCount : -1;
bool loggingThisObject = (!gObjectsToLog || LogThisObj(serialno));
if (gCOMPtrLog && loggingThisObject) {
fprintf(gCOMPtrLog, "\n<?> %p %" PRIdPTR " nsCOMPtrAddRef %d %p\n",
object, serialno, count, aCOMPtr);
WalkTheStackCached(gCOMPtrLog, CallerPC());
}
}
#endif // HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR
}
EXPORT_XPCOM_API(MOZ_NEVER_INLINE void)
NS_LogCOMPtrRelease(void* aCOMPtr, nsISupports* aObject) {
#ifdef HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR
// Get the most-derived object.
void* object = dynamic_cast<void*>(aObject);
// This is a very indirect way of finding out what the class is
// of the object being logged. If we're logging a specific type,
// then
if (!gTypesToLog || !gSerialNumbers) {
return;
}
if (!gInitialized) {
InitTraceLog();
}
if (gLogging == FullLogging) {
AutoTraceLogLock lock;
intptr_t serialno = GetSerialNumber(object, false, CallerPC());
if (serialno == 0) {
return;
}
auto record = gSerialNumbers->Get(object);
int32_t count = record ? --record->COMPtrCount : -1;
bool loggingThisObject = (!gObjectsToLog || LogThisObj(serialno));
if (gCOMPtrLog && loggingThisObject) {
fprintf(gCOMPtrLog, "\n<?> %p %" PRIdPTR " nsCOMPtrRelease %d %p\n",
object, serialno, count, aCOMPtr);
WalkTheStackCached(gCOMPtrLog, CallerPC());
}
}
#endif // HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR
}
static void ClearLogs(bool aKeepCounters) {
gCodeAddressService = nullptr;
// These counters from the fork server process will be preserved
// for the content processes to keep them consistent.
if (!aKeepCounters) {
gBloatView = nullptr;
gTypesToLog = nullptr;
gSerialNumbers = nullptr;
}
gObjectsToLog = nullptr;
gLogJSStacks = false;
gLogLeaksOnly = false;
maybeUnregisterAndCloseFile(gBloatLog);
maybeUnregisterAndCloseFile(gRefcntsLog);
maybeUnregisterAndCloseFile(gAllocLog);
maybeUnregisterAndCloseFile(gCOMPtrLog);
}
void nsTraceRefcnt::Shutdown() { ClearLogs(false); }
void nsTraceRefcnt::SetActivityIsLegal(bool aLegal) {
if (gActivityTLS == BAD_TLS_INDEX) {
PR_NewThreadPrivateIndex(&gActivityTLS, nullptr);
}
PR_SetThreadPrivate(gActivityTLS, reinterpret_cast<void*>(!aLegal));
}
#ifdef MOZ_ENABLE_FORKSERVER
void nsTraceRefcnt::ResetLogFiles(const char* aProcType) {
AutoRestore<LoggingType> saveLogging(gLogging);
gLogging = NoLogging;
ClearLogs(true);
// Create log files with the correct process type in the name.
DoInitTraceLog(aProcType);
}
#endif