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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
#include "vm/GeckoProfiler-inl.h"
#include "mozilla/DebugOnly.h"
#include "mozilla/Sprintf.h"
#include "gc/GC.h"
#include "gc/PublicIterators.h"
#include "jit/BaselineJIT.h"
#include "jit/JitcodeMap.h"
#include "jit/JitRuntime.h"
#include "jit/JSJitFrameIter.h"
#include "jit/PerfSpewer.h"
#include "js/ProfilingStack.h"
#include "vm/FrameIter.h" // js::OnlyJSJitFrameIter
#include "vm/JitActivation.h"
#include "vm/JSScript.h"
#include "gc/Marking-inl.h"
#include "jit/JSJitFrameIter-inl.h"
using namespace js;
GeckoProfilerThread::GeckoProfilerThread()
: profilingStack_(nullptr), profilingStackIfEnabled_(nullptr) {}
GeckoProfilerRuntime::GeckoProfilerRuntime(JSRuntime* rt)
: rt(rt), slowAssertions(false), enabled_(false), eventMarker_(nullptr) {
MOZ_ASSERT(rt != nullptr);
}
void GeckoProfilerThread::setProfilingStack(ProfilingStack* profilingStack,
bool enabled) {
profilingStack_ = profilingStack;
profilingStackIfEnabled_ = enabled ? profilingStack : nullptr;
}
void GeckoProfilerRuntime::setEventMarker(void (*fn)(const char*,
const char*)) {
eventMarker_ = fn;
}
// Get a pointer to the top-most profiling frame, given the exit frame pointer.
static jit::JitFrameLayout* GetTopProfilingJitFrame(jit::JitActivation* act) {
// If there is no exit frame set, just return.
if (!act->hasExitFP()) {
return nullptr;
}
// Skip wasm frames that might be in the way.
OnlyJSJitFrameIter iter(act);
if (iter.done()) {
return nullptr;
}
// Skip if the activation has no JS frames. This can happen if there's only a
// TrampolineNative frame because these are skipped by the profiling frame
// iterator.
jit::JSJitProfilingFrameIterator jitIter(
(jit::CommonFrameLayout*)iter.frame().fp());
if (jitIter.done()) {
return nullptr;
}
return jitIter.framePtr();
}
void GeckoProfilerRuntime::enable(bool enabled) {
JSContext* cx = rt->mainContextFromAnyThread();
MOZ_ASSERT(cx->geckoProfiler().infraInstalled());
if (enabled_ == enabled) {
return;
}
/*
* Ensure all future generated code will be instrumented, or that all
* currently instrumented code is discarded
*/
ReleaseAllJITCode(rt->gcContext());
// This function is called when the Gecko profiler makes a new Sampler
// (and thus, a new circular buffer). Set all current entries in the
// JitcodeGlobalTable as expired and reset the buffer range start.
if (rt->hasJitRuntime() && rt->jitRuntime()->hasJitcodeGlobalTable()) {
rt->jitRuntime()->getJitcodeGlobalTable()->setAllEntriesAsExpired();
}
rt->setProfilerSampleBufferRangeStart(0);
// Ensure that lastProfilingFrame is null for the main thread.
if (cx->jitActivation) {
cx->jitActivation->setLastProfilingFrame(nullptr);
cx->jitActivation->setLastProfilingCallSite(nullptr);
}
enabled_ = enabled;
/* Toggle Gecko Profiler-related jumps on baseline jitcode.
* The call to |ReleaseAllJITCode| above will release most baseline jitcode,
* but not jitcode for scripts with active frames on the stack. These scripts
* need to have their profiler state toggled so they behave properly.
*/
jit::ToggleBaselineProfiling(cx, enabled);
// Update lastProfilingFrame to point to the top-most JS jit-frame currently
// on stack.
if (cx->jitActivation) {
// Walk through all activations, and set their lastProfilingFrame
// appropriately.
if (enabled) {
jit::JitActivation* jitActivation = cx->jitActivation;
while (jitActivation) {
auto* lastProfilingFrame = GetTopProfilingJitFrame(jitActivation);
jitActivation->setLastProfilingFrame(lastProfilingFrame);
jitActivation->setLastProfilingCallSite(nullptr);
jitActivation = jitActivation->prevJitActivation();
}
} else {
jit::JitActivation* jitActivation = cx->jitActivation;
while (jitActivation) {
jitActivation->setLastProfilingFrame(nullptr);
jitActivation->setLastProfilingCallSite(nullptr);
jitActivation = jitActivation->prevJitActivation();
}
}
}
// WebAssembly code does not need to be released, but profiling string
// labels have to be generated so that they are available during async
// profiling stack iteration.
for (RealmsIter r(rt); !r.done(); r.next()) {
r->wasm.ensureProfilingLabels(enabled);
}
#ifdef JS_STRUCTURED_SPEW
// Enable the structured spewer if the environment variable is set.
if (enabled) {
cx->spewer().enableSpewing();
} else {
cx->spewer().disableSpewing();
}
#endif
}
/* Lookup the string for the function/script, creating one if necessary */
const char* GeckoProfilerRuntime::profileString(JSContext* cx,
BaseScript* script) {
ProfileStringMap::AddPtr s = strings().lookupForAdd(script);
if (!s) {
UniqueChars str = allocProfileString(cx, script);
if (!str) {
return nullptr;
}
MOZ_ASSERT(script->hasBytecode());
if (!strings().add(s, script, std::move(str))) {
ReportOutOfMemory(cx);
return nullptr;
}
}
return s->value().get();
}
void GeckoProfilerRuntime::onScriptFinalized(BaseScript* script) {
/*
* This function is called whenever a script is destroyed, regardless of
* whether profiling has been turned on, so don't invoke a function on an
* invalid hash set. Also, even if profiling was enabled but then turned
* off, we still want to remove the string, so no check of enabled() is
* done.
*/
if (ProfileStringMap::Ptr entry = strings().lookup(script)) {
strings().remove(entry);
}
}
void GeckoProfilerRuntime::markEvent(const char* event, const char* details) {
MOZ_ASSERT(enabled());
if (eventMarker_) {
JS::AutoSuppressGCAnalysis nogc;
eventMarker_(event, details);
}
}
bool GeckoProfilerThread::enter(JSContext* cx, JSScript* script) {
const char* dynamicString =
cx->runtime()->geckoProfiler().profileString(cx, script);
if (dynamicString == nullptr) {
return false;
}
#ifdef DEBUG
// In debug builds, assert the JS profiling stack frames already on the
// stack have a non-null pc. Only look at the top frames to avoid quadratic
// behavior.
uint32_t sp = profilingStack_->stackPointer;
if (sp > 0 && sp - 1 < profilingStack_->stackCapacity()) {
size_t start = (sp > 4) ? sp - 4 : 0;
for (size_t i = start; i < sp - 1; i++) {
MOZ_ASSERT_IF(profilingStack_->frames[i].isJsFrame(),
profilingStack_->frames[i].pc());
}
}
#endif
profilingStack_->pushJsFrame(
"", dynamicString, script, script->code(),
script->realm()->creationOptions().profilerRealmID());
return true;
}
void GeckoProfilerThread::exit(JSContext* cx, JSScript* script) {
profilingStack_->pop();
#ifdef DEBUG
/* Sanity check to make sure push/pop balanced */
uint32_t sp = profilingStack_->stackPointer;
if (sp < profilingStack_->stackCapacity()) {
JSRuntime* rt = script->runtimeFromMainThread();
const char* dynamicString = rt->geckoProfiler().profileString(cx, script);
/* Can't fail lookup because we should already be in the set */
MOZ_ASSERT(dynamicString);
if (!profilingStack_->frames[sp].isJsFrame()) {
fprintf(stderr, "--- ABOUT TO FAIL ASSERTION ---\n");
fprintf(stderr, " frames=%p size=%u/%u\n", (void*)profilingStack_->frames,
uint32_t(profilingStack_->stackPointer),
profilingStack_->stackCapacity());
for (int32_t i = sp; i >= 0; i--) {
ProfilingStackFrame& frame = profilingStack_->frames[i];
if (frame.isJsFrame()) {
fprintf(stderr, " [%d] JS %s\n", i, frame.dynamicString());
} else {
fprintf(stderr, " [%d] Label %s\n", i, frame.dynamicString());
}
}
}
ProfilingStackFrame& frame = profilingStack_->frames[sp];
MOZ_ASSERT(frame.isJsFrame());
MOZ_ASSERT(frame.script() == script);
MOZ_ASSERT(strcmp((const char*)frame.dynamicString(), dynamicString) == 0);
}
#endif
}
/*
* Serializes the script/function pair into a "descriptive string" which is
* allowed to fail. This function cannot trigger a GC because it could finalize
* some scripts, resize the hash table of profile strings, and invalidate the
* AddPtr held while invoking allocProfileString.
*/
/* static */
UniqueChars GeckoProfilerRuntime::allocProfileString(JSContext* cx,
BaseScript* script) {
// Note: this profiler string is regexp-matched by
// profiler code. Most recently at
// If the script has a function, try calculating its name.
JSAtom* name = nullptr;
size_t nameLength = 0;
JSFunction* func = script->function();
if (func && func->fullDisplayAtom()) {
name = func->fullDisplayAtom();
nameLength = JS::GetDeflatedUTF8StringLength(name);
}
// Calculate filename length. We cap this to a reasonable limit to avoid
// performance impact of strlen/alloc/memcpy.
constexpr size_t MaxFilenameLength = 200;
const char* filenameStr = script->filename() ? script->filename() : "(null)";
size_t filenameLength = js_strnlen(filenameStr, MaxFilenameLength);
// Calculate line + column length.
bool hasLineAndColumn = false;
size_t lineAndColumnLength = 0;
char lineAndColumnStr[30];
if (name || script->isFunction() || script->isForEval()) {
lineAndColumnLength =
SprintfLiteral(lineAndColumnStr, "%u:%u", script->lineno(),
script->column().oneOriginValue());
hasLineAndColumn = true;
}
// Full profile string for scripts with functions is:
// FuncName (FileName:Lineno:Column)
// Full profile string for scripts without functions is:
// FileName:Lineno:Column
// Full profile string for scripts without functions and without lines is:
// FileName
// Calculate full string length.
size_t fullLength = 0;
if (name) {
MOZ_ASSERT(hasLineAndColumn);
fullLength = nameLength + 2 + filenameLength + 1 + lineAndColumnLength + 1;
} else if (hasLineAndColumn) {
fullLength = filenameLength + 1 + lineAndColumnLength;
} else {
fullLength = filenameLength;
}
// Allocate string.
UniqueChars str(cx->pod_malloc<char>(fullLength + 1));
if (!str) {
return nullptr;
}
size_t cur = 0;
// Fill string with function name if needed.
if (name) {
mozilla::DebugOnly<size_t> written = JS::DeflateStringToUTF8Buffer(
name, mozilla::Span(str.get() + cur, nameLength));
MOZ_ASSERT(written == nameLength);
cur += nameLength;
str[cur++] = ' ';
str[cur++] = '(';
}
// Fill string with filename chars.
memcpy(str.get() + cur, filenameStr, filenameLength);
cur += filenameLength;
// Fill line + column chars.
if (hasLineAndColumn) {
str[cur++] = ':';
memcpy(str.get() + cur, lineAndColumnStr, lineAndColumnLength);
cur += lineAndColumnLength;
}
// Terminal ')' if necessary.
if (name) {
str[cur++] = ')';
}
MOZ_ASSERT(cur == fullLength);
str[cur] = 0;
return str;
}
void GeckoProfilerThread::trace(JSTracer* trc) {
if (profilingStack_) {
size_t size = profilingStack_->stackSize();
for (size_t i = 0; i < size; i++) {
profilingStack_->frames[i].trace(trc);
}
}
}
void GeckoProfilerRuntime::fixupStringsMapAfterMovingGC() {
for (ProfileStringMap::Enum e(strings()); !e.empty(); e.popFront()) {
BaseScript* script = e.front().key();
if (IsForwarded(script)) {
script = Forwarded(script);
e.rekeyFront(script);
}
}
}
#ifdef JSGC_HASH_TABLE_CHECKS
void GeckoProfilerRuntime::checkStringsMapAfterMovingGC() {
CheckTableAfterMovingGC(strings(), [](const auto& entry) {
BaseScript* script = entry.key();
CheckGCThingAfterMovingGC(script);
return script;
});
}
#endif
void ProfilingStackFrame::trace(JSTracer* trc) {
if (isJsFrame()) {
JSScript* s = rawScript();
TraceNullableRoot(trc, &s, "ProfilingStackFrame script");
spOrScript = s;
}
}
GeckoProfilerBaselineOSRMarker::GeckoProfilerBaselineOSRMarker(
JSContext* cx, bool hasProfilerFrame)
: profiler(&cx->geckoProfiler()) {
if (!hasProfilerFrame || !cx->runtime()->geckoProfiler().enabled()) {
profiler = nullptr;
return;
}
uint32_t sp = profiler->profilingStack_->stackPointer;
if (sp >= profiler->profilingStack_->stackCapacity()) {
profiler = nullptr;
return;
}
spBefore_ = sp;
if (sp == 0) {
return;
}
ProfilingStackFrame& frame = profiler->profilingStack_->frames[sp - 1];
MOZ_ASSERT(!frame.isOSRFrame());
frame.setIsOSRFrame(true);
}
GeckoProfilerBaselineOSRMarker::~GeckoProfilerBaselineOSRMarker() {
if (profiler == nullptr) {
return;
}
uint32_t sp = profiler->stackPointer();
MOZ_ASSERT(spBefore_ == sp);
if (sp == 0) {
return;
}
ProfilingStackFrame& frame = profiler->stack()[sp - 1];
MOZ_ASSERT(frame.isOSRFrame());
frame.setIsOSRFrame(false);
}
JS_PUBLIC_API JSScript* ProfilingStackFrame::script() const {
MOZ_ASSERT(isJsFrame());
auto* script = reinterpret_cast<JSScript*>(spOrScript.operator void*());
if (!script) {
return nullptr;
}
// If profiling is supressed then we can't trust the script pointers to be
// valid as they could be in the process of being moved by a compacting GC
// (although it's still OK to get the runtime from them).
JSContext* cx = script->runtimeFromAnyThread()->mainContextFromAnyThread();
if (!cx->isProfilerSamplingEnabled()) {
return nullptr;
}
MOZ_ASSERT(!IsForwarded(script));
return script;
}
JS_PUBLIC_API JSFunction* ProfilingStackFrame::function() const {
JSScript* script = this->script();
return script ? script->function() : nullptr;
}
JS_PUBLIC_API jsbytecode* ProfilingStackFrame::pc() const {
MOZ_ASSERT(isJsFrame());
if (pcOffsetIfJS_ == NullPCOffset) {
return nullptr;
}
JSScript* script = this->script();
return script ? script->offsetToPC(pcOffsetIfJS_) : nullptr;
}
/* static */
int32_t ProfilingStackFrame::pcToOffset(JSScript* aScript, jsbytecode* aPc) {
return aPc ? aScript->pcToOffset(aPc) : NullPCOffset;
}
void ProfilingStackFrame::setPC(jsbytecode* pc) {
MOZ_ASSERT(isJsFrame());
JSScript* script = this->script();
MOZ_ASSERT(
script); // This should not be called while profiling is suppressed.
pcOffsetIfJS_ = pcToOffset(script, pc);
}
JS_PUBLIC_API void js::SetContextProfilingStack(
JSContext* cx, ProfilingStack* profilingStack) {
cx->geckoProfiler().setProfilingStack(
profilingStack, cx->runtime()->geckoProfiler().enabled());
}
JS_PUBLIC_API void js::EnableContextProfilingStack(JSContext* cx,
bool enabled) {
cx->geckoProfiler().enable(enabled);
cx->runtime()->geckoProfiler().enable(enabled);
}
JS_PUBLIC_API void js::RegisterContextProfilingEventMarker(
JSContext* cx, void (*fn)(const char*, const char*)) {
MOZ_ASSERT(cx->runtime()->geckoProfiler().enabled());
cx->runtime()->geckoProfiler().setEventMarker(fn);
}
AutoSuppressProfilerSampling::AutoSuppressProfilerSampling(JSContext* cx)
: cx_(cx), previouslyEnabled_(cx->isProfilerSamplingEnabled()) {
if (previouslyEnabled_) {
cx_->disableProfilerSampling();
}
}
AutoSuppressProfilerSampling::~AutoSuppressProfilerSampling() {
if (previouslyEnabled_) {
cx_->enableProfilerSampling();
}
}
namespace JS {
// clang-format off
// ProfilingSubcategory_X:
// One enum for each category X, listing that category's subcategories. This
// allows the sProfilingCategoryInfo macro construction below to look up a
// per-category index for a subcategory.
#define SUBCATEGORY_ENUMS_BEGIN_CATEGORY(name, labelAsString, color) \
enum class ProfilingSubcategory_##name : uint32_t {
#define SUBCATEGORY_ENUMS_SUBCATEGORY(category, name, labelAsString) \
name,
#define SUBCATEGORY_ENUMS_END_CATEGORY \
};
MOZ_PROFILING_CATEGORY_LIST(SUBCATEGORY_ENUMS_BEGIN_CATEGORY,
SUBCATEGORY_ENUMS_SUBCATEGORY,
SUBCATEGORY_ENUMS_END_CATEGORY)
#undef SUBCATEGORY_ENUMS_BEGIN_CATEGORY
#undef SUBCATEGORY_ENUMS_SUBCATEGORY
#undef SUBCATEGORY_ENUMS_END_CATEGORY
// sProfilingCategoryPairInfo:
// A list of ProfilingCategoryPairInfos with the same order as
// ProfilingCategoryPair, which can be used to map a ProfilingCategoryPair to
// its information.
#define CATEGORY_INFO_BEGIN_CATEGORY(name, labelAsString, color)
#define CATEGORY_INFO_SUBCATEGORY(category, name, labelAsString) \
{ProfilingCategory::category, \
uint32_t(ProfilingSubcategory_##category::name), labelAsString},
#define CATEGORY_INFO_END_CATEGORY
const ProfilingCategoryPairInfo sProfilingCategoryPairInfo[] = {
MOZ_PROFILING_CATEGORY_LIST(CATEGORY_INFO_BEGIN_CATEGORY,
CATEGORY_INFO_SUBCATEGORY,
CATEGORY_INFO_END_CATEGORY)
};
#undef CATEGORY_INFO_BEGIN_CATEGORY
#undef CATEGORY_INFO_SUBCATEGORY
#undef CATEGORY_INFO_END_CATEGORY
// clang-format on
JS_PUBLIC_API const ProfilingCategoryPairInfo& GetProfilingCategoryPairInfo(
ProfilingCategoryPair aCategoryPair) {
static_assert(
std::size(sProfilingCategoryPairInfo) ==
uint32_t(ProfilingCategoryPair::COUNT),
"sProfilingCategoryPairInfo and ProfilingCategory need to have the "
"same order and the same length");
uint32_t categoryPairIndex = uint32_t(aCategoryPair);
MOZ_RELEASE_ASSERT(categoryPairIndex <=
uint32_t(ProfilingCategoryPair::LAST));
return sProfilingCategoryPairInfo[categoryPairIndex];
}
} // namespace JS