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-rw-r--r--xpcom/base/nsTraceRefcnt.cpp1198
1 files changed, 1198 insertions, 0 deletions
diff --git a/xpcom/base/nsTraceRefcnt.cpp b/xpcom/base/nsTraceRefcnt.cpp
new file mode 100644
index 0000000000..8836de7b5f
--- /dev/null
+++ b/xpcom/base/nsTraceRefcnt.cpp
@@ -0,0 +1,1198 @@
+/* -*- 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/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 "plstr.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);
+
+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 = PL_strdup(aClassName);
+ mStats.Clear();
+ mTotalLeaked = 0;
+ }
+
+ ~BloatEntry() { PL_strfree(mClassName); }
+
+ 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:
+ 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 = new BloatEntry(aTypeName, aInstanceSize);
+ gBloatView->Put(aTypeName, entry);
+ } 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::Iterator& 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 PL_strcmp(aEntry1->GetClassName(), aEntry2->GetClassName()) == 0;
+ }
+ bool LessThan(BloatEntry* const& aEntry1, BloatEntry* const& aEntry2) const {
+ return PL_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 (auto iter = gBloatView->Iter(); !iter.Done(); iter.Next()) {
+ BloatEntry* entry = iter.UserData();
+ if (nsCRT::strcmp(entry->GetClassName(), "TOTAL") != 0) {
+ entry->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;
+ for (auto iter = gBloatView->Iter(); !iter.Done(); iter.Next()) {
+ entries.AppendElement(iter.UserData());
+ }
+
+ 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->Iter(); !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) {
+ if (!aCreate) {
+ auto record = gSerialNumbers->Get(aPtr);
+ return record ? record->serialNumber : 0;
+ }
+
+ auto entry = gSerialNumbers->LookupForAdd(aPtr);
+ if (entry) {
+ MOZ_CRASH(
+ "If an object already has a serial number, we should be destroying "
+ "it.");
+ }
+
+ auto& record = entry.OrInsert([]() { return new SerialNumberRecord(); });
+ WalkTheStackSavingLocations(record->allocationStack);
+ 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;
+ } else if (fname.EqualsLiteral("2")) {
+ *aResult = stderr;
+ fprintf(stdout, "### " ENVVAR_PRINTF " defined -- logging %s to stderr\n",
+ envvar, aMsg);
+ return true;
+ } else {
+ 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);
+ } else {
+ 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 stream != nullptr;
+ }
+ }
+ 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 PrintStackFrame(uint32_t aFrameNumber, void* aPC, void* aSP,
+ void* aClosure) {
+ FILE* stream = (FILE*)aClosure;
+ MozCodeAddressDetails details;
+ static const size_t buflen = 1024;
+ char buf[buflen + 1]; // 1 for trailing '\n'
+
+ MozDescribeCodeAddress(aPC, &details);
+ MozFormatCodeAddressDetails(buf, buflen, aFrameNumber, aPC, &details);
+ size_t len = std::min(strlen(buf), buflen + 1 - 2);
+ buf[len++] = '\n';
+ buf[len] = '\0';
+ fflush(stream);
+ EnsureWrite(stream, buf, len);
+}
+
+static void PrintStackFrameCached(uint32_t aFrameNumber, void* aPC, void* aSP,
+ void* aClosure) {
+ auto stream = static_cast<FILE*>(aClosure);
+ static const size_t buflen = 1024;
+ char buf[buflen + 5] = " "; // 5 for leading " " and trailing '\n'
+ gCodeAddressService->GetLocation(aFrameNumber, aPC, buf + 4, buflen);
+ size_t len = std::min(strlen(buf), buflen + 5 - 2);
+ 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);
+}
+}
+
+void nsTraceRefcnt::WalkTheStack(FILE* aStream, uint32_t aMaxFrames) {
+ MozStackWalk(PrintStackFrame, /* skipFrames */ 2, aMaxFrames, aStream);
+}
+
+#ifdef ANDROID
+void nsTraceRefcnt::WalkTheStack(void (*aWriter)(uint32_t, void*, void*,
+ void*)) {
+ MozStackWalk(aWriter, /* skipFrames */ 2, /* maxFrames */ 0, nullptr);
+}
+#endif
+
+/**
+ * This is a variant of |WalkTheStack| 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
+ * |WalkTheStack|. 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) {
+ if (!gCodeAddressService) {
+ gCodeAddressService = new CodeAddressService<>();
+ }
+ MozStackWalk(PrintStackFrameCached, /* skipFrames */ 2, /* maxFrames */ 0,
+ aStream);
+}
+
+static void WalkTheStackSavingLocations(std::vector<void*>& aLocations) {
+ if (!gCodeAddressService) {
+ gCodeAddressService = new CodeAddressService<>();
+ }
+ static const int kFramesToSkip = 0 + // this frame gets inlined
+ 1 + // GetSerialNumber
+ 1; // NS_LogCtor
+ MozStackWalk(RecordStackFrame, kFramesToSkip, /* 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(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);
+ 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);
+ }
+
+ 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);
+ fflush(gRefcntsLog);
+ }
+ }
+}
+
+EXPORT_XPCOM_API(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);
+ 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);
+ 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);
+ }
+
+ if (aRefcnt == 0 && gSerialNumbers && loggingThisType) {
+ RecycleSerialNumberPtr(aPtr);
+ }
+ }
+}
+
+EXPORT_XPCOM_API(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);
+ 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);
+ }
+}
+
+EXPORT_XPCOM_API(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);
+ 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);
+ }
+}
+
+EXPORT_XPCOM_API(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);
+ 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);
+ }
+ }
+#endif // HAVE_CPP_DYNAMIC_CAST_TO_VOID_PTR
+}
+
+EXPORT_XPCOM_API(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);
+ 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);
+ }
+ }
+#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