gecko/tools/profiler/TableTicker.cpp

1196 lines
33 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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 <string>
#include <stdio.h>
#include <iostream>
#include <fstream>
#include <sstream>
#include "sps_sampler.h"
#include "platform.h"
#include "nsXULAppAPI.h"
#include "nsThreadUtils.h"
#include "prenv.h"
#include "shared-libraries.h"
#include "mozilla/StackWalk.h"
// JSON
#include "JSObjectBuilder.h"
#include "nsIJSRuntimeService.h"
// Meta
#include "nsXPCOM.h"
#include "nsXPCOMCID.h"
#include "nsIHttpProtocolHandler.h"
#include "nsServiceManagerUtils.h"
#include "nsIXULRuntime.h"
#include "nsIXULAppInfo.h"
#include "nsDirectoryServiceUtils.h"
#include "nsDirectoryServiceDefs.h"
#include "nsIObserverService.h"
#include "mozilla/Services.h"
// JS
#include "jsdbgapi.h"
// we eventually want to make this runtime switchable
#if defined(MOZ_PROFILING) && (defined(XP_UNIX) && !defined(XP_MACOSX))
#ifndef ANDROID
#define USE_BACKTRACE
#endif
#endif
#ifdef USE_BACKTRACE
#include <execinfo.h>
#endif
#if defined(MOZ_PROFILING) && (defined(XP_MACOSX) || defined(XP_WIN))
#define USE_NS_STACKWALK
#endif
#ifdef USE_NS_STACKWALK
#include "nsStackWalk.h"
#endif
#if defined(MOZ_PROFILING) && defined(ANDROID)
#define USE_LIBUNWIND
#include <libunwind.h>
#include "android-signal-defs.h"
#endif
using std::string;
using namespace mozilla;
#ifdef XP_WIN
#include <windows.h>
#define getpid GetCurrentProcessId
#else
#include <unistd.h>
#endif
#ifndef MAXPATHLEN
#ifdef PATH_MAX
#define MAXPATHLEN PATH_MAX
#elif defined(MAX_PATH)
#define MAXPATHLEN MAX_PATH
#elif defined(_MAX_PATH)
#define MAXPATHLEN _MAX_PATH
#elif defined(CCHMAXPATH)
#define MAXPATHLEN CCHMAXPATH
#else
#define MAXPATHLEN 1024
#endif
#endif
#if _MSC_VER
#define snprintf _snprintf
#endif
static const int DYNAMIC_MAX_STRING = 512;
mozilla::ThreadLocal<ProfileStack *> tlsStack;
mozilla::ThreadLocal<TableTicker *> tlsTicker;
// We need to track whether we've been initialized otherwise
// we end up using tlsStack without initializing it.
// Because tlsStack is totally opaque to us we can't reuse
// it as the flag itself.
bool stack_key_initialized;
TimeStamp sLastTracerEvent;
int sFrameNumber = 0;
int sLastFrameNumber = 0;
class ThreadProfile;
class ProfileEntry
{
public:
ProfileEntry()
: mTagData(NULL)
, mTagName(0)
{ }
// aTagData must not need release (i.e. be a string from the text segment)
ProfileEntry(char aTagName, const char *aTagData)
: mTagData(aTagData)
, mTagName(aTagName)
{ }
ProfileEntry(char aTagName, void *aTagPtr)
: mTagPtr(aTagPtr)
, mTagName(aTagName)
{ }
ProfileEntry(char aTagName, double aTagFloat)
: mTagFloat(aTagFloat)
, mTagName(aTagName)
{ }
ProfileEntry(char aTagName, uintptr_t aTagOffset)
: mTagOffset(aTagOffset)
, mTagName(aTagName)
{ }
ProfileEntry(char aTagName, Address aTagAddress)
: mTagAddress(aTagAddress)
, mTagName(aTagName)
{ }
ProfileEntry(char aTagName, int aTagLine)
: mTagLine(aTagLine)
, mTagName(aTagName)
{ }
friend std::ostream& operator<<(std::ostream& stream, const ProfileEntry& entry);
private:
friend class ThreadProfile;
union {
const char* mTagData;
char mTagChars[sizeof(void*)];
void* mTagPtr;
double mTagFloat;
Address mTagAddress;
uintptr_t mTagOffset;
int mTagLine;
};
char mTagName;
};
#define PROFILE_MAX_ENTRY 100000
class ThreadProfile
{
public:
ThreadProfile(int aEntrySize, ProfileStack *aStack)
: mWritePos(0)
, mLastFlushPos(0)
, mReadPos(0)
, mEntrySize(aEntrySize)
, mStack(aStack)
{
mEntries = new ProfileEntry[mEntrySize];
}
~ThreadProfile()
{
delete[] mEntries;
}
void addTag(ProfileEntry aTag)
{
// Called from signal, call only reentrant functions
mEntries[mWritePos] = aTag;
mWritePos = (mWritePos + 1) % mEntrySize;
if (mWritePos == mReadPos) {
// Keep one slot open
mEntries[mReadPos] = ProfileEntry();
mReadPos = (mReadPos + 1) % mEntrySize;
}
// we also need to move the flush pos to ensure we
// do not pass it
if (mWritePos == mLastFlushPos) {
mLastFlushPos = (mLastFlushPos + 1) % mEntrySize;
}
}
// flush the new entries
void flush()
{
mLastFlushPos = mWritePos;
}
// discards all of the entries since the last flush()
// NOTE: that if mWritePos happens to wrap around past
// mLastFlushPos we actually only discard mWritePos - mLastFlushPos entries
//
// r = mReadPos
// w = mWritePos
// f = mLastFlushPos
//
// r f w
// |-----------------------------|
// | abcdefghijklmnopq | -> 'abcdefghijklmnopq'
// |-----------------------------|
//
//
// mWritePos and mReadPos have passed mLastFlushPos
// f
// w r
// |-----------------------------|
// |ABCDEFGHIJKLMNOPQRSqrstuvwxyz|
// |-----------------------------|
// w
// r
// |-----------------------------|
// |ABCDEFGHIJKLMNOPQRSqrstuvwxyz| -> ''
// |-----------------------------|
//
//
// mWritePos will end up the same as mReadPos
// r
// w f
// |-----------------------------|
// |ABCDEFGHIJKLMklmnopqrstuvwxyz|
// |-----------------------------|
// r
// w
// |-----------------------------|
// |ABCDEFGHIJKLMklmnopqrstuvwxyz| -> ''
// |-----------------------------|
//
//
// mWritePos has moved past mReadPos
// w r f
// |-----------------------------|
// |ABCDEFdefghijklmnopqrstuvwxyz|
// |-----------------------------|
// r w
// |-----------------------------|
// |ABCDEFdefghijklmnopqrstuvwxyz| -> 'defghijkl'
// |-----------------------------|
void erase()
{
mWritePos = mLastFlushPos;
}
char* processDynamicTag(int readPos, int* tagsConsumed, char* tagBuff)
{
int readAheadPos = (readPos + 1) % mEntrySize;
int tagBuffPos = 0;
// Read the string stored in mTagData until the null character is seen
bool seenNullByte = false;
while (readAheadPos != mLastFlushPos && !seenNullByte) {
(*tagsConsumed)++;
ProfileEntry readAheadEntry = mEntries[readAheadPos];
for (size_t pos = 0; pos < sizeof(void*); pos++) {
tagBuff[tagBuffPos] = readAheadEntry.mTagChars[pos];
if (tagBuff[tagBuffPos] == '\0' || tagBuffPos == DYNAMIC_MAX_STRING-2) {
seenNullByte = true;
break;
}
tagBuffPos++;
}
if (!seenNullByte)
readAheadPos = (readAheadPos + 1) % mEntrySize;
}
return tagBuff;
}
friend std::ostream& operator<<(std::ostream& stream, const ThreadProfile& profile);
JSObject *ToJSObject(JSContext *aCx)
{
JSObjectBuilder b(aCx);
JSObject *profile = b.CreateObject();
JSObject *samples = b.CreateArray();
b.DefineProperty(profile, "samples", samples);
JSObject *sample = NULL;
JSObject *frames = NULL;
JSObject *marker = NULL;
int readPos = mReadPos;
while (readPos != mLastFlushPos) {
// Number of tag consumed
int incBy = 1;
ProfileEntry entry = mEntries[readPos];
// Read ahead to the next tag, if it's a 'd' tag process it now
const char* tagStringData = entry.mTagData;
int readAheadPos = (readPos + 1) % mEntrySize;
char tagBuff[DYNAMIC_MAX_STRING];
// Make sure the string is always null terminated if it fills up DYNAMIC_MAX_STRING-2
tagBuff[DYNAMIC_MAX_STRING-1] = '\0';
if (readAheadPos != mLastFlushPos && mEntries[readAheadPos].mTagName == 'd') {
tagStringData = processDynamicTag(readPos, &incBy, tagBuff);
}
switch (entry.mTagName) {
case 's':
sample = b.CreateObject();
b.DefineProperty(sample, "name", tagStringData);
frames = b.CreateArray();
b.DefineProperty(sample, "frames", frames);
b.ArrayPush(samples, sample);
// Created lazily
marker = NULL;
break;
case 'm':
{
if (sample) {
if (!marker) {
marker = b.CreateArray();
b.DefineProperty(sample, "marker", marker);
}
b.ArrayPush(marker, tagStringData);
}
}
break;
case 'r':
{
if (sample) {
b.DefineProperty(sample, "responsiveness", entry.mTagFloat);
}
}
break;
case 'f':
{
if (sample) {
b.DefineProperty(sample, "frameNumber", entry.mTagLine);
}
}
break;
case 't':
{
if (sample) {
b.DefineProperty(sample, "time", entry.mTagFloat);
}
}
break;
case 'c':
case 'l':
{
if (sample) {
JSObject *frame = b.CreateObject();
if (entry.mTagName == 'l') {
// Bug 753041
// We need a double cast here to tell GCC that we don't want to sign
// extend 32-bit addresses starting with 0xFXXXXXX.
unsigned long long pc = (unsigned long long)(uintptr_t)entry.mTagPtr;
snprintf(tagBuff, DYNAMIC_MAX_STRING, "%#llx", pc);
b.DefineProperty(frame, "location", tagBuff);
} else {
b.DefineProperty(frame, "location", tagStringData);
readAheadPos = (readPos + incBy) % mEntrySize;
if (readAheadPos != mLastFlushPos &&
mEntries[readAheadPos].mTagName == 'n') {
b.DefineProperty(frame, "line",
mEntries[readAheadPos].mTagLine);
incBy++;
}
}
b.ArrayPush(frames, frame);
}
}
}
readPos = (readPos + incBy) % mEntrySize;
}
return profile;
}
ProfileStack* GetStack()
{
return mStack;
}
private:
// Circular buffer 'Keep One Slot Open' implementation
// for simplicity
ProfileEntry *mEntries;
int mWritePos; // points to the next entry we will write to
int mLastFlushPos; // points to the next entry since the last flush()
int mReadPos; // points to the next entry we will read to
int mEntrySize;
ProfileStack *mStack;
};
class SaveProfileTask;
static bool
hasFeature(const char** aFeatures, uint32_t aFeatureCount, const char* aFeature) {
for(size_t i = 0; i < aFeatureCount; i++) {
if (strcmp(aFeatures[i], aFeature) == 0)
return true;
}
return false;
}
class TableTicker: public Sampler {
public:
TableTicker(int aInterval, int aEntrySize, ProfileStack *aStack,
const char** aFeatures, uint32_t aFeatureCount)
: Sampler(aInterval, true)
, mPrimaryThreadProfile(aEntrySize, aStack)
, mStartTime(TimeStamp::Now())
, mSaveRequested(false)
{
mUseStackWalk = hasFeature(aFeatures, aFeatureCount, "stackwalk");
//XXX: It's probably worth splitting the jank profiler out from the regular profiler at some point
mJankOnly = hasFeature(aFeatures, aFeatureCount, "jank");
mProfileJS = hasFeature(aFeatures, aFeatureCount, "js");
mPrimaryThreadProfile.addTag(ProfileEntry('m', "Start"));
}
~TableTicker() { if (IsActive()) Stop(); }
virtual void SampleStack(TickSample* sample) {}
// Called within a signal. This function must be reentrant
virtual void Tick(TickSample* sample);
// Called within a signal. This function must be reentrant
virtual void RequestSave()
{
mSaveRequested = true;
}
virtual void HandleSaveRequest();
ThreadProfile* GetPrimaryThreadProfile()
{
return &mPrimaryThreadProfile;
}
JSObject *ToJSObject(JSContext *aCx);
JSObject *GetMetaJSObject(JSObjectBuilder& b);
const bool ProfileJS() { return mProfileJS; }
private:
// Not implemented on platforms which do not support backtracing
void doBacktrace(ThreadProfile &aProfile, TickSample* aSample);
private:
// This represent the application's main thread (SAMPLER_INIT)
ThreadProfile mPrimaryThreadProfile;
TimeStamp mStartTime;
bool mSaveRequested;
bool mUseStackWalk;
bool mJankOnly;
bool mProfileJS;
};
std::string GetSharedLibraryInfoString();
static JSBool
WriteCallback(const jschar *buf, uint32_t len, void *data)
{
std::ofstream& stream = *static_cast<std::ofstream*>(data);
nsAutoCString profile = NS_ConvertUTF16toUTF8(buf, len);
stream << profile.Data();
return JS_TRUE;
}
/**
* This is an event used to save the profile on the main thread
* to be sure that it is not being modified while saving.
*/
class SaveProfileTask : public nsRunnable {
public:
SaveProfileTask() {}
NS_IMETHOD Run() {
TableTicker *t = tlsTicker.get();
// Pause the profiler during saving.
// This will prevent us from recording sampling
// regarding profile saving. This will also
// prevent bugs caused by the circular buffer not
// being thread safe. Bug 750989.
t->SetPaused(true);
// Get file path
#ifdef MOZ_WIDGET_ANDROID
nsCString tmpPath;
tmpPath.AppendPrintf("/sdcard/profile_%i_%i.txt", XRE_GetProcessType(), getpid());
#else
nsCOMPtr<nsIFile> tmpFile;
nsAutoCString tmpPath;
if (NS_FAILED(NS_GetSpecialDirectory(NS_OS_TEMP_DIR, getter_AddRefs(tmpFile)))) {
LOG("Failed to find temporary directory.");
return NS_ERROR_FAILURE;
}
tmpPath.AppendPrintf("profile_%i_%i.txt", XRE_GetProcessType(), getpid());
nsresult rv = tmpFile->AppendNative(tmpPath);
if (NS_FAILED(rv))
return rv;
rv = tmpFile->GetNativePath(tmpPath);
if (NS_FAILED(rv))
return rv;
#endif
// Create a JSContext to run a JSObjectBuilder :(
// Based on XPCShellEnvironment
JSRuntime *rt;
JSContext *cx;
nsCOMPtr<nsIJSRuntimeService> rtsvc = do_GetService("@mozilla.org/js/xpc/RuntimeService;1");
if (!rtsvc || NS_FAILED(rtsvc->GetRuntime(&rt)) || !rt) {
LOG("failed to get RuntimeService");
return NS_ERROR_FAILURE;;
}
cx = JS_NewContext(rt, 8192);
if (!cx) {
LOG("Failed to get context");
return NS_ERROR_FAILURE;
}
{
JSAutoRequest ar(cx);
static JSClass c = {
"global", JSCLASS_GLOBAL_FLAGS,
JS_PropertyStub, JS_PropertyStub, JS_PropertyStub, JS_StrictPropertyStub,
JS_EnumerateStub, JS_ResolveStub, JS_ConvertStub
};
JSObject *obj = JS_NewGlobalObject(cx, &c, NULL);
std::ofstream stream;
stream.open(tmpPath.get());
// Pause the profiler during saving.
// This will prevent us from recording sampling
// regarding profile saving. This will also
// prevent bugs caused by the circular buffer not
// being thread safe. Bug 750989.
t->SetPaused(true);
if (stream.is_open()) {
JSAutoCompartment autoComp(cx, obj);
JSObject* profileObj = mozilla_sampler_get_profile_data(cx);
jsval val = OBJECT_TO_JSVAL(profileObj);
JS_Stringify(cx, &val, nullptr, JSVAL_NULL, WriteCallback, &stream);
stream.close();
LOGF("Saved to %s", tmpPath.get());
} else {
LOG("Fail to open profile log file.");
}
}
JS_EndRequest(cx);
JS_DestroyContext(cx);
t->SetPaused(false);
return NS_OK;
}
};
void TableTicker::HandleSaveRequest()
{
if (!mSaveRequested)
return;
mSaveRequested = false;
// TODO: Use use the ipc/chromium Tasks here to support processes
// without XPCOM.
nsCOMPtr<nsIRunnable> runnable = new SaveProfileTask();
NS_DispatchToMainThread(runnable);
}
JSObject* TableTicker::GetMetaJSObject(JSObjectBuilder& b)
{
JSObject *meta = b.CreateObject();
b.DefineProperty(meta, "version", 2);
b.DefineProperty(meta, "interval", interval());
b.DefineProperty(meta, "stackwalk", mUseStackWalk);
b.DefineProperty(meta, "jank", mJankOnly);
b.DefineProperty(meta, "processType", XRE_GetProcessType());
nsresult res;
nsCOMPtr<nsIHttpProtocolHandler> http = do_GetService(NS_NETWORK_PROTOCOL_CONTRACTID_PREFIX "http", &res);
if (!NS_FAILED(res)) {
nsAutoCString string;
res = http->GetPlatform(string);
if (!NS_FAILED(res))
b.DefineProperty(meta, "platform", string.Data());
res = http->GetOscpu(string);
if (!NS_FAILED(res))
b.DefineProperty(meta, "oscpu", string.Data());
res = http->GetMisc(string);
if (!NS_FAILED(res))
b.DefineProperty(meta, "misc", string.Data());
}
nsCOMPtr<nsIXULRuntime> runtime = do_GetService("@mozilla.org/xre/runtime;1");
if (runtime) {
nsAutoCString string;
res = runtime->GetXPCOMABI(string);
if (!NS_FAILED(res))
b.DefineProperty(meta, "abi", string.Data());
res = runtime->GetWidgetToolkit(string);
if (!NS_FAILED(res))
b.DefineProperty(meta, "toolkit", string.Data());
}
nsCOMPtr<nsIXULAppInfo> appInfo = do_GetService("@mozilla.org/xre/app-info;1");
if (appInfo) {
nsAutoCString string;
res = appInfo->GetName(string);
if (!NS_FAILED(res))
b.DefineProperty(meta, "product", string.Data());
}
return meta;
}
JSObject* TableTicker::ToJSObject(JSContext *aCx)
{
JSObjectBuilder b(aCx);
JSObject *profile = b.CreateObject();
// Put shared library info
b.DefineProperty(profile, "libs", GetSharedLibraryInfoString().c_str());
// Put meta data
JSObject *meta = GetMetaJSObject(b);
b.DefineProperty(profile, "meta", meta);
// Lists the samples for each ThreadProfile
JSObject *threads = b.CreateArray();
b.DefineProperty(profile, "threads", threads);
// For now we only have one thread
SetPaused(true);
JSObject* threadSamples = GetPrimaryThreadProfile()->ToJSObject(aCx);
b.ArrayPush(threads, threadSamples);
SetPaused(false);
return profile;
}
static
void addProfileEntry(volatile StackEntry &entry, ThreadProfile &aProfile,
ProfileStack *stack, void *lastpc)
{
int lineno = -1;
// First entry has tagName 's' (start)
// Check for magic pointer bit 1 to indicate copy
const char* sampleLabel = entry.label();
if (entry.isCopyLabel()) {
// Store the string using 1 or more 'd' (dynamic) tags
// that will happen to the preceding tag
aProfile.addTag(ProfileEntry('c', ""));
// Add one to store the null termination
size_t strLen = strlen(sampleLabel) + 1;
for (size_t j = 0; j < strLen;) {
// Store as many characters in the void* as the platform allows
char text[sizeof(void*)];
for (size_t pos = 0; pos < sizeof(void*) && j+pos < strLen; pos++) {
text[pos] = sampleLabel[j+pos];
}
j += sizeof(void*)/sizeof(char);
// Cast to *((void**) to pass the text data to a void*
aProfile.addTag(ProfileEntry('d', *((void**)(&text[0]))));
}
if (entry.js()) {
if (!entry.pc()) {
// The JIT only allows the top-most entry to have a NULL pc
MOZ_ASSERT(&entry == &stack->mStack[stack->stackSize() - 1]);
// If stack-walking was disabled, then that's just unfortunate
if (lastpc) {
jsbytecode *jspc = js::ProfilingGetPC(stack->mRuntime, entry.script(),
lastpc);
if (jspc) {
lineno = JS_PCToLineNumber(NULL, entry.script(), jspc);
}
}
} else {
lineno = JS_PCToLineNumber(NULL, entry.script(), entry.pc());
}
} else {
lineno = entry.line();
}
} else {
aProfile.addTag(ProfileEntry('c', sampleLabel));
lineno = entry.line();
}
if (lineno != -1) {
aProfile.addTag(ProfileEntry('n', lineno));
}
}
#ifdef USE_BACKTRACE
void TableTicker::doBacktrace(ThreadProfile &aProfile, TickSample* aSample)
{
void *array[100];
int count = backtrace (array, 100);
aProfile.addTag(ProfileEntry('s', "(root)"));
for (int i = 0; i < count; i++) {
if( (intptr_t)array[i] == -1 ) break;
aProfile.addTag(ProfileEntry('l', (void*)array[i]));
}
}
#endif
#ifdef USE_NS_STACKWALK
typedef struct {
void** array;
void** sp_array;
size_t size;
size_t count;
} PCArray;
static
void StackWalkCallback(void* aPC, void* aSP, void* aClosure)
{
PCArray* array = static_cast<PCArray*>(aClosure);
if (array->count >= array->size) {
// too many frames, ignore
return;
}
array->sp_array[array->count] = aSP;
array->array[array->count] = aPC;
array->count++;
}
void TableTicker::doBacktrace(ThreadProfile &aProfile, TickSample* aSample)
{
#ifndef XP_MACOSX
uintptr_t thread = GetThreadHandle(platform_data());
MOZ_ASSERT(thread);
#endif
void* pc_array[1000];
void* sp_array[1000];
PCArray array = {
pc_array,
sp_array,
mozilla::ArrayLength(pc_array),
0
};
// Start with the current function.
StackWalkCallback(aSample->pc, aSample->sp, &array);
#ifdef XP_MACOSX
pthread_t pt = GetProfiledThread(platform_data());
void *stackEnd = reinterpret_cast<void*>(-1);
if (pt)
stackEnd = static_cast<char*>(pthread_get_stackaddr_np(pt));
nsresult rv = FramePointerStackWalk(StackWalkCallback, 0, &array, reinterpret_cast<void**>(aSample->fp), stackEnd);
#else
nsresult rv = NS_StackWalk(StackWalkCallback, 0, &array, thread);
#endif
if (NS_SUCCEEDED(rv)) {
aProfile.addTag(ProfileEntry('s', "(root)"));
ProfileStack* stack = aProfile.GetStack();
int pseudoStackPos = 0;
/* We have two stacks, the native C stack we extracted from unwinding,
* and the pseudostack we managed during execution. We want to consolidate
* the two in order. We do so by merging using the approximate stack address
* when each entry was push. When pushing JS entry we may not now the stack
* address in which case we have a NULL stack address in which case we assume
* that it follows immediatly the previous element.
*
* C Stack | Address -- Pseudo Stack | Address
* main() | 0x100 run_js() | 0x40
* start() | 0x80 jsCanvas() | NULL
* timer() | 0x50 drawLine() | NULL
* azure() | 0x10
*
* Merged: main(), start(), timer(), run_js(), jsCanvas(), drawLine(), azure()
*/
// i is the index in C stack starting at main and decreasing
// pseudoStackPos is the position in the Pseudo stack starting
// at the first frame (run_js in the example) and increasing.
for (size_t i = array.count; i > 0; --i) {
while (pseudoStackPos < stack->stackSize()) {
volatile StackEntry& entry = stack->mStack[pseudoStackPos];
if (entry.stackAddress() < array.sp_array[i-1] && entry.stackAddress())
break;
addProfileEntry(entry, aProfile, stack, array.array[0]);
pseudoStackPos++;
}
aProfile.addTag(ProfileEntry('l', (void*)array.array[i-1]));
}
}
}
#endif
#if defined(USE_LIBUNWIND) && defined(ANDROID)
void TableTicker::doBacktrace(ThreadProfile &aProfile, TickSample* aSample)
{
void* pc_array[1000];
size_t count = 0;
unw_cursor_t cursor; unw_context_t uc;
unw_word_t ip;
unw_getcontext(&uc);
// Dirty hack: replace the registers with values from the signal handler
// We do this in order to avoid the overhead of walking up to reach the
// signal handler frame, and the possibility that libunwind fails to
// handle it correctly.
unw_tdep_context_t *unw_ctx = reinterpret_cast<unw_tdep_context_t*> (&uc);
mcontext_t& mcontext = reinterpret_cast<ucontext_t*> (aSample->context)->uc_mcontext;
#define REPLACE_REG(num) unw_ctx->regs[num] = mcontext.gregs[R##num]
REPLACE_REG(0);
REPLACE_REG(1);
REPLACE_REG(2);
REPLACE_REG(3);
REPLACE_REG(4);
REPLACE_REG(5);
REPLACE_REG(6);
REPLACE_REG(7);
REPLACE_REG(8);
REPLACE_REG(9);
REPLACE_REG(10);
REPLACE_REG(11);
REPLACE_REG(12);
REPLACE_REG(13);
REPLACE_REG(14);
REPLACE_REG(15);
#undef REPLACE_REG
unw_init_local(&cursor, &uc);
while (count < ArrayLength(pc_array) &&
unw_step(&cursor) > 0) {
unw_get_reg(&cursor, UNW_REG_IP, &ip);
pc_array[count++] = reinterpret_cast<void*> (ip);
}
aProfile.addTag(ProfileEntry('s', "(root)"));
for (size_t i = count; i > 0; --i) {
aProfile.addTag(ProfileEntry('l', reinterpret_cast<void*>(pc_array[i - 1])));
}
}
#endif
static
void doSampleStackTrace(ProfileStack *aStack, ThreadProfile &aProfile, TickSample *sample)
{
// Sample
// 's' tag denotes the start of a sample block
// followed by 0 or more 'c' tags.
aProfile.addTag(ProfileEntry('s', "(root)"));
for (uint32_t i = 0; i < aStack->stackSize(); i++) {
addProfileEntry(aStack->mStack[i], aProfile, aStack, nullptr);
}
#ifdef ENABLE_SPS_LEAF_DATA
if (sample) {
aProfile.addTag(ProfileEntry('l', (void*)sample->pc));
#ifdef ENABLE_ARM_LR_SAVING
aProfile.addTag(ProfileEntry('L', (void*)sample->lr));
#endif
}
#endif
}
/* used to keep track of the last event that we sampled during */
unsigned int sLastSampledEventGeneration = 0;
/* a counter that's incremented everytime we get responsiveness event
* note: it might also be worth tracking everytime we go around
* the event loop */
unsigned int sCurrentEventGeneration = 0;
/* we don't need to worry about overflow because we only treat the
* case of them being the same as special. i.e. we only run into
* a problem if 2^32 events happen between samples that we need
* to know are associated with different events */
void TableTicker::Tick(TickSample* sample)
{
// Marker(s) come before the sample
ProfileStack* stack = mPrimaryThreadProfile.GetStack();
for (int i = 0; stack->getMarker(i) != NULL; i++) {
mPrimaryThreadProfile.addTag(ProfileEntry('m', stack->getMarker(i)));
}
stack->mQueueClearMarker = true;
bool recordSample = true;
if (mJankOnly) {
// if we are on a different event we can discard any temporary samples
// we've kept around
if (sLastSampledEventGeneration != sCurrentEventGeneration) {
// XXX: we also probably want to add an entry to the profile to help
// distinguish which samples are part of the same event. That, or record
// the event generation in each sample
mPrimaryThreadProfile.erase();
}
sLastSampledEventGeneration = sCurrentEventGeneration;
recordSample = false;
// only record the events when we have a we haven't seen a tracer event for 100ms
if (!sLastTracerEvent.IsNull()) {
TimeDuration delta = sample->timestamp - sLastTracerEvent;
if (delta.ToMilliseconds() > 100.0) {
recordSample = true;
}
}
}
#if defined(USE_BACKTRACE) || defined(USE_NS_STACKWALK) || defined(USE_LIBUNWIND)
if (mUseStackWalk) {
doBacktrace(mPrimaryThreadProfile, sample);
} else {
doSampleStackTrace(stack, mPrimaryThreadProfile, sample);
}
#else
doSampleStackTrace(stack, mPrimaryThreadProfile, sample);
#endif
if (recordSample)
mPrimaryThreadProfile.flush();
if (!sLastTracerEvent.IsNull() && sample) {
TimeDuration delta = sample->timestamp - sLastTracerEvent;
mPrimaryThreadProfile.addTag(ProfileEntry('r', delta.ToMilliseconds()));
}
if (sample) {
TimeDuration delta = sample->timestamp - mStartTime;
mPrimaryThreadProfile.addTag(ProfileEntry('t', delta.ToMilliseconds()));
}
if (sLastFrameNumber != sFrameNumber) {
mPrimaryThreadProfile.addTag(ProfileEntry('f', sFrameNumber));
sLastFrameNumber = sFrameNumber;
}
}
std::ostream& operator<<(std::ostream& stream, const ThreadProfile& profile)
{
int readPos = profile.mReadPos;
while (readPos != profile.mLastFlushPos) {
stream << profile.mEntries[readPos];
readPos = (readPos + 1) % profile.mEntrySize;
}
return stream;
}
std::ostream& operator<<(std::ostream& stream, const ProfileEntry& entry)
{
if (entry.mTagName == 'r' || entry.mTagName == 't') {
stream << entry.mTagName << "-" << std::fixed << entry.mTagFloat << "\n";
} else if (entry.mTagName == 'l' || entry.mTagName == 'L') {
// Bug 739800 - Force l-tag addresses to have a "0x" prefix on all platforms
// Additionally, stringstream seemed to be ignoring formatter flags.
char tagBuff[1024];
unsigned long long pc = (unsigned long long)(uintptr_t)entry.mTagPtr;
snprintf(tagBuff, 1024, "%c-%#llx\n", entry.mTagName, pc);
stream << tagBuff;
} else if (entry.mTagName == 'd') {
// TODO implement 'd' tag for text profile
} else {
stream << entry.mTagName << "-" << entry.mTagData << "\n";
}
return stream;
}
void mozilla_sampler_init()
{
if (stack_key_initialized)
return;
if (!tlsStack.init() || !tlsTicker.init()) {
LOG("Failed to init.");
return;
}
stack_key_initialized = true;
ProfileStack *stack = new ProfileStack();
tlsStack.set(stack);
#if defined(USE_LIBUNWIND) && defined(ANDROID)
// Only try debug_frame and exidx unwinding
putenv("UNW_ARM_UNWIND_METHOD=5");
#endif
// Allow the profiler to be started using signals
OS::RegisterStartHandler();
#if defined(USE_LIBUNWIND) && defined(__arm__) && defined(MOZ_CRASHREPORTER)
// On ARM, libunwind defines a signal handler for segmentation faults.
// If SPS is enabled now, the crash reporter will override that signal
// handler, and libunwind will likely break.
return;
#endif
// We can't open pref so we use an environment variable
// to know if we should trigger the profiler on startup
// NOTE: Default
const char *val = PR_GetEnv("MOZ_PROFILER_STARTUP");
if (!val || !*val) {
return;
}
const char* features[] = {"js"
#if defined(XP_WIN) || defined(XP_MACOSX)
, "stackwalk"
#endif
};
mozilla_sampler_start(PROFILE_DEFAULT_ENTRY, PROFILE_DEFAULT_INTERVAL,
features, sizeof(features)/sizeof(const char*));
}
void mozilla_sampler_deinit()
{
mozilla_sampler_stop();
// We can't delete the Stack because we can be between a
// sampler call_enter/call_exit point.
// TODO Need to find a safe time to delete Stack
}
void mozilla_sampler_save()
{
TableTicker *t = tlsTicker.get();
if (!t) {
return;
}
t->RequestSave();
// We're on the main thread already so we don't
// have to wait to handle the save request.
t->HandleSaveRequest();
}
char* mozilla_sampler_get_profile()
{
TableTicker *t = tlsTicker.get();
if (!t) {
return NULL;
}
std::stringstream profile;
t->SetPaused(true);
profile << *(t->GetPrimaryThreadProfile());
t->SetPaused(false);
std::string profileString = profile.str();
char *rtn = (char*)malloc( (profileString.length() + 1) * sizeof(char) );
strcpy(rtn, profileString.c_str());
return rtn;
}
JSObject *mozilla_sampler_get_profile_data(JSContext *aCx)
{
TableTicker *t = tlsTicker.get();
if (!t) {
return NULL;
}
return t->ToJSObject(aCx);
}
const char** mozilla_sampler_get_features()
{
static const char* features[] = {
#if defined(MOZ_PROFILING) && (defined(USE_BACKTRACE) || defined(USE_NS_STACKWALK) || defined(USE_LIBUNWIND))
"stackwalk",
#endif
"jank",
"js",
NULL
};
return features;
}
// Values are only honored on the first start
void mozilla_sampler_start(int aProfileEntries, int aInterval,
const char** aFeatures, uint32_t aFeatureCount)
{
if (!stack_key_initialized)
mozilla_sampler_init();
ProfileStack *stack = tlsStack.get();
if (!stack) {
ASSERT(false);
return;
}
mozilla_sampler_stop();
TableTicker *t = new TableTicker(aInterval ? aInterval : PROFILE_DEFAULT_INTERVAL,
aProfileEntries ? aProfileEntries : PROFILE_DEFAULT_ENTRY,
stack, aFeatures, aFeatureCount);
tlsTicker.set(t);
t->Start();
if (t->ProfileJS())
stack->enableJSSampling();
nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
if (os)
os->NotifyObservers(nullptr, "profiler-started", nullptr);
}
void mozilla_sampler_stop()
{
if (!stack_key_initialized)
mozilla_sampler_init();
TableTicker *t = tlsTicker.get();
if (!t) {
return;
}
bool disableJS = t->ProfileJS();
t->Stop();
delete t;
tlsTicker.set(NULL);
ProfileStack *stack = tlsStack.get();
ASSERT(stack != NULL);
if (disableJS)
stack->disableJSSampling();
nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
if (os)
os->NotifyObservers(nullptr, "profiler-stopped", nullptr);
}
bool mozilla_sampler_is_active()
{
if (!stack_key_initialized)
mozilla_sampler_init();
TableTicker *t = tlsTicker.get();
if (!t) {
return false;
}
return t->IsActive();
}
double sResponsivenessTimes[100];
double sCurrResponsiveness = 0.f;
unsigned int sResponsivenessLoc = 0;
void mozilla_sampler_responsiveness(TimeStamp aTime)
{
if (!sLastTracerEvent.IsNull()) {
if (sResponsivenessLoc == 100) {
for(size_t i = 0; i < 100-1; i++) {
sResponsivenessTimes[i] = sResponsivenessTimes[i+1];
}
sResponsivenessLoc--;
}
TimeDuration delta = aTime - sLastTracerEvent;
sResponsivenessTimes[sResponsivenessLoc++] = delta.ToMilliseconds();
}
sCurrentEventGeneration++;
sLastTracerEvent = aTime;
}
const double* mozilla_sampler_get_responsiveness()
{
return sResponsivenessTimes;
}
void mozilla_sampler_frame_number(int frameNumber)
{
sFrameNumber = frameNumber;
}