/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "instrumentation.h"
#include <sstream>
#include <android-base/logging.h>
#include "arch/context.h"
#include "art_field-inl.h"
#include "art_method-inl.h"
#include "base/atomic.h"
#include "base/callee_save_type.h"
#include "class_linker.h"
#include "debugger.h"
#include "dex/dex_file-inl.h"
#include "dex/dex_file_types.h"
#include "dex/dex_instruction-inl.h"
#include "entrypoints/quick/quick_alloc_entrypoints.h"
#include "entrypoints/quick/quick_entrypoints.h"
#include "entrypoints/runtime_asm_entrypoints.h"
#include "gc_root-inl.h"
#include "interpreter/interpreter.h"
#include "interpreter/interpreter_common.h"
#include "jit/jit.h"
#include "jit/jit_code_cache.h"
#include "jvalue-inl.h"
#include "mirror/class-inl.h"
#include "mirror/dex_cache.h"
#include "mirror/object-inl.h"
#include "mirror/object_array-inl.h"
#include "nth_caller_visitor.h"
#include "oat_quick_method_header.h"
#include "runtime-inl.h"
#include "thread.h"
#include "thread_list.h"
namespace art {
namespace instrumentation {
constexpr bool kVerboseInstrumentation = false;
void InstrumentationListener::MethodExited(Thread* thread,
Handle<mirror::Object> this_object,
ArtMethod* method,
uint32_t dex_pc,
Handle<mirror::Object> return_value) {
DCHECK_EQ(method->GetInterfaceMethodIfProxy(kRuntimePointerSize)->GetReturnTypePrimitive(),
Primitive::kPrimNot);
JValue v;
v.SetL(return_value.Get());
MethodExited(thread, this_object, method, dex_pc, v);
}
void InstrumentationListener::FieldWritten(Thread* thread,
Handle<mirror::Object> this_object,
ArtMethod* method,
uint32_t dex_pc,
ArtField* field,
Handle<mirror::Object> field_value) {
DCHECK(!field->IsPrimitiveType());
JValue v;
v.SetL(field_value.Get());
FieldWritten(thread, this_object, method, dex_pc, field, v);
}
// Instrumentation works on non-inlined frames by updating returned PCs
// of compiled frames.
static constexpr StackVisitor::StackWalkKind kInstrumentationStackWalk =
StackVisitor::StackWalkKind::kSkipInlinedFrames;
class InstallStubsClassVisitor : public ClassVisitor {
public:
explicit InstallStubsClassVisitor(Instrumentation* instrumentation)
: instrumentation_(instrumentation) {}
bool operator()(ObjPtr<mirror::Class> klass) override REQUIRES(Locks::mutator_lock_) {
instrumentation_->InstallStubsForClass(klass.Ptr());
return true; // we visit all classes.
}
private:
Instrumentation* const instrumentation_;
};
InstrumentationStackPopper::InstrumentationStackPopper(Thread* self)
: self_(self),
instrumentation_(Runtime::Current()->GetInstrumentation()),
frames_to_remove_(0) {}
InstrumentationStackPopper::~InstrumentationStackPopper() {
std::deque<instrumentation::InstrumentationStackFrame>* stack = self_->GetInstrumentationStack();
for (size_t i = 0; i < frames_to_remove_; i++) {
stack->pop_front();
}
}
bool InstrumentationStackPopper::PopFramesTo(uint32_t desired_pops,
MutableHandle<mirror::Throwable>& exception) {
std::deque<instrumentation::InstrumentationStackFrame>* stack = self_->GetInstrumentationStack();
DCHECK_LE(frames_to_remove_, desired_pops);
DCHECK_GE(stack->size(), desired_pops);
DCHECK(!self_->IsExceptionPending());
if (!instrumentation_->HasMethodUnwindListeners()) {
frames_to_remove_ = desired_pops;
return true;
}
if (kVerboseInstrumentation) {
LOG(INFO) << "Popping frames for exception " << exception->Dump();
}
// The instrumentation events expect the exception to be set.
self_->SetException(exception.Get());
bool new_exception_thrown = false;
for (; frames_to_remove_ < desired_pops && !new_exception_thrown; frames_to_remove_++) {
InstrumentationStackFrame frame = stack->at(frames_to_remove_);
ArtMethod* method = frame.method_;
// Notify listeners of method unwind.
// TODO: improve the dex_pc information here.
uint32_t dex_pc = dex::kDexNoIndex;
if (kVerboseInstrumentation) {
LOG(INFO) << "Popping for unwind " << method->PrettyMethod();
}
if (!method->IsRuntimeMethod() && !frame.interpreter_entry_) {
instrumentation_->MethodUnwindEvent(self_, frame.this_object_, method, dex_pc);
new_exception_thrown = self_->GetException() != exception.Get();
}
}
exception.Assign(self_->GetException());
self_->ClearException();
if (kVerboseInstrumentation && new_exception_thrown) {
LOG(INFO) << "Failed to pop " << (desired_pops - frames_to_remove_)
<< " frames due to new exception";
}
return !new_exception_thrown;
}
Instrumentation::Instrumentation()
: instrumentation_stubs_installed_(false),
entry_exit_stubs_installed_(false),
interpreter_stubs_installed_(false),
interpret_only_(false),
forced_interpret_only_(false),
have_method_entry_listeners_(false),
have_method_exit_listeners_(false),
have_method_unwind_listeners_(false),
have_dex_pc_listeners_(false),
have_field_read_listeners_(false),
have_field_write_listeners_(false),
have_exception_thrown_listeners_(false),
have_watched_frame_pop_listeners_(false),
have_branch_listeners_(false),
have_exception_handled_listeners_(false),
deoptimized_methods_lock_(new ReaderWriterMutex("deoptimized methods lock",
kGenericBottomLock)),
deoptimization_enabled_(false),
interpreter_handler_table_(kMainHandlerTable),
quick_alloc_entry_points_instrumentation_counter_(0),
alloc_entrypoints_instrumented_(false),
can_use_instrumentation_trampolines_(true) {
}
void Instrumentation::InstallStubsForClass(mirror::Class* klass) {
if (!klass->IsResolved()) {
// We need the class to be resolved to install/uninstall stubs. Otherwise its methods
// could not be initialized or linked with regards to class inheritance.
} else if (klass->IsErroneousResolved()) {
// We can't execute code in a erroneous class: do nothing.
} else {
for (ArtMethod& method : klass->GetMethods(kRuntimePointerSize)) {
InstallStubsForMethod(&method);
}
}
}
static void UpdateEntrypoints(ArtMethod* method, const void* quick_code)
REQUIRES_SHARED(Locks::mutator_lock_) {
method->SetEntryPointFromQuickCompiledCode(quick_code);
}
bool Instrumentation::NeedDebugVersionFor(ArtMethod* method) const
REQUIRES_SHARED(Locks::mutator_lock_) {
art::Runtime* runtime = Runtime::Current();
// If anything says we need the debug version or we are debuggable we will need the debug version
// of the method.
return (runtime->GetRuntimeCallbacks()->MethodNeedsDebugVersion(method) ||
runtime->IsJavaDebuggable()) &&
!method->IsNative() &&
!method->IsProxyMethod();
}
void Instrumentation::InstallStubsForMethod(ArtMethod* method) {
if (!method->IsInvokable() || method->IsProxyMethod()) {
// Do not change stubs for these methods.
return;
}
// Don't stub Proxy.<init>. Note that the Proxy class itself is not a proxy class.
// TODO We should remove the need for this since it means we cannot always correctly detect calls
// to Proxy.<init>
// Annoyingly this can be called before we have actually initialized WellKnownClasses so therefore
// we also need to check this based on the declaring-class descriptor. The check is valid because
// Proxy only has a single constructor.
ArtMethod* well_known_proxy_init = jni::DecodeArtMethod(
WellKnownClasses::java_lang_reflect_Proxy_init);
if ((LIKELY(well_known_proxy_init != nullptr) && UNLIKELY(method == well_known_proxy_init)) ||
UNLIKELY(method->IsConstructor() &&
method->GetDeclaringClass()->DescriptorEquals("Ljava/lang/reflect/Proxy;"))) {
return;
}
const void* new_quick_code;
bool uninstall = !entry_exit_stubs_installed_ && !interpreter_stubs_installed_;
Runtime* const runtime = Runtime::Current();
ClassLinker* const class_linker = runtime->GetClassLinker();
bool is_class_initialized = method->GetDeclaringClass()->IsInitialized();
if (uninstall) {
if ((forced_interpret_only_ || IsDeoptimized(method)) && !method->IsNative()) {
new_quick_code = GetQuickToInterpreterBridge();
} else if (is_class_initialized || !method->IsStatic() || method->IsConstructor()) {
new_quick_code = GetCodeForInvoke(method);
} else {
new_quick_code = GetQuickResolutionStub();
}
} else { // !uninstall
if ((interpreter_stubs_installed_ || forced_interpret_only_ || IsDeoptimized(method)) &&
!method->IsNative()) {
new_quick_code = GetQuickToInterpreterBridge();
} else {
// Do not overwrite resolution trampoline. When the trampoline initializes the method's
// class, all its static methods code will be set to the instrumentation entry point.
// For more details, see ClassLinker::FixupStaticTrampolines.
if (is_class_initialized || !method->IsStatic() || method->IsConstructor()) {
if (entry_exit_stubs_installed_) {
// This needs to be checked first since the instrumentation entrypoint will be able to
// find the actual JIT compiled code that corresponds to this method.
new_quick_code = GetQuickInstrumentationEntryPoint();
} else if (NeedDebugVersionFor(method)) {
// It would be great to search the JIT for its implementation here but we cannot due to
// the locks we hold. Instead just set to the interpreter bridge and that code will search
// the JIT when it gets called and replace the entrypoint then.
new_quick_code = GetQuickToInterpreterBridge();
} else {
new_quick_code = class_linker->GetQuickOatCodeFor(method);
}
} else {
new_quick_code = GetQuickResolutionStub();
}
}
}
UpdateEntrypoints(method, new_quick_code);
}
// Places the instrumentation exit pc as the return PC for every quick frame. This also allows
// deoptimization of quick frames to interpreter frames.
// Since we may already have done this previously, we need to push new instrumentation frame before
// existing instrumentation frames.
static void InstrumentationInstallStack(Thread* thread, void* arg)
REQUIRES_SHARED(Locks::mutator_lock_) {
struct InstallStackVisitor final : public StackVisitor {
InstallStackVisitor(Thread* thread_in, Context* context, uintptr_t instrumentation_exit_pc)
: StackVisitor(thread_in, context, kInstrumentationStackWalk),
instrumentation_stack_(thread_in->GetInstrumentationStack()),
instrumentation_exit_pc_(instrumentation_exit_pc),
reached_existing_instrumentation_frames_(false), instrumentation_stack_depth_(0),
last_return_pc_(0) {
}
bool VisitFrame() override REQUIRES_SHARED(Locks::mutator_lock_) {
ArtMethod* m = GetMethod();
if (m == nullptr) {
if (kVerboseInstrumentation) {
LOG(INFO) << " Skipping upcall. Frame " << GetFrameId();
}
last_return_pc_ = 0;
return true; // Ignore upcalls.
}
if (GetCurrentQuickFrame() == nullptr) {
bool interpreter_frame = true;
InstrumentationStackFrame instrumentation_frame(GetThisObject(), m, 0, GetFrameId(),
interpreter_frame);
if (kVerboseInstrumentation) {
LOG(INFO) << "Pushing shadow frame " << instrumentation_frame.Dump();
}
shadow_stack_.push_back(instrumentation_frame);
return true; // Continue.
}
uintptr_t return_pc = GetReturnPc();
if (kVerboseInstrumentation) {
LOG(INFO) << " Installing exit stub in " << DescribeLocation();
}
if (return_pc == instrumentation_exit_pc_) {
CHECK_LT(instrumentation_stack_depth_, instrumentation_stack_->size());
if (m->IsRuntimeMethod()) {
const InstrumentationStackFrame& frame =
(*instrumentation_stack_)[instrumentation_stack_depth_];
if (frame.interpreter_entry_) {
// This instrumentation frame is for an interpreter bridge and is
// pushed when executing the instrumented interpreter bridge. So method
// enter event must have been reported. However we need to push a DEX pc
// into the dex_pcs_ list to match size of instrumentation stack.
uint32_t dex_pc = dex::kDexNoIndex;
dex_pcs_.push_back(dex_pc);
last_return_pc_ = frame.return_pc_;
++instrumentation_stack_depth_;
return true;
}
}
// We've reached a frame which has already been installed with instrumentation exit stub.
// We should have already installed instrumentation or be interpreter on previous frames.
reached_existing_instrumentation_frames_ = true;
const InstrumentationStackFrame& frame =
(*instrumentation_stack_)[instrumentation_stack_depth_];
CHECK_EQ(m->GetNonObsoleteMethod(), frame.method_->GetNonObsoleteMethod())
<< "Expected " << ArtMethod::PrettyMethod(m)
<< ", Found " << ArtMethod::PrettyMethod(frame.method_);
return_pc = frame.return_pc_;
if (kVerboseInstrumentation) {
LOG(INFO) << "Ignoring already instrumented " << frame.Dump();
}
} else {
CHECK_NE(return_pc, 0U);
if (UNLIKELY(reached_existing_instrumentation_frames_ && !m->IsRuntimeMethod())) {
// We already saw an existing instrumentation frame so this should be a runtime-method
// inserted by the interpreter or runtime.
std::string thread_name;
GetThread()->GetThreadName(thread_name);
uint32_t dex_pc = dex::kDexNoIndex;
if (last_return_pc_ != 0 &&
GetCurrentOatQuickMethodHeader() != nullptr) {
dex_pc = GetCurrentOatQuickMethodHeader()->ToDexPc(m, last_return_pc_);
}
LOG(FATAL) << "While walking " << thread_name << " found unexpected non-runtime method"
<< " without instrumentation exit return or interpreter frame."
<< " method is " << GetMethod()->PrettyMethod()
<< " return_pc is " << std::hex << return_pc
<< " dex pc: " << dex_pc;
UNREACHABLE();
}
InstrumentationStackFrame instrumentation_frame(
m->IsRuntimeMethod() ? nullptr : GetThisObject(),
m,
return_pc,
GetFrameId(), // A runtime method still gets a frame id.
false);
if (kVerboseInstrumentation) {
LOG(INFO) << "Pushing frame " << instrumentation_frame.Dump();
}
// Insert frame at the right position so we do not corrupt the instrumentation stack.
// Instrumentation stack frames are in descending frame id order.
auto it = instrumentation_stack_->begin();
for (auto end = instrumentation_stack_->end(); it != end; ++it) {
const InstrumentationStackFrame& current = *it;
if (instrumentation_frame.frame_id_ >= current.frame_id_) {
break;
}
}
instrumentation_stack_->insert(it, instrumentation_frame);
SetReturnPc(instrumentation_exit_pc_);
}
uint32_t dex_pc = dex::kDexNoIndex;
if (last_return_pc_ != 0 &&
GetCurrentOatQuickMethodHeader() != nullptr) {
dex_pc = GetCurrentOatQuickMethodHeader()->ToDexPc(m, last_return_pc_);
}
dex_pcs_.push_back(dex_pc);
last_return_pc_ = return_pc;
++instrumentation_stack_depth_;
return true; // Continue.
}
std::deque<InstrumentationStackFrame>* const instrumentation_stack_;
std::vector<InstrumentationStackFrame> shadow_stack_;
std::vector<uint32_t> dex_pcs_;
const uintptr_t instrumentation_exit_pc_;
bool reached_existing_instrumentation_frames_;
size_t instrumentation_stack_depth_;
uintptr_t last_return_pc_;
};
if (kVerboseInstrumentation) {
std::string thread_name;
thread->GetThreadName(thread_name);
LOG(INFO) << "Installing exit stubs in " << thread_name;
}
Instrumentation* instrumentation = reinterpret_cast<Instrumentation*>(arg);
std::unique_ptr<Context> context(Context::Create());
uintptr_t instrumentation_exit_pc = reinterpret_cast<uintptr_t>(GetQuickInstrumentationExitPc());
InstallStackVisitor visitor(thread, context.get(), instrumentation_exit_pc);
visitor.WalkStack(true);
CHECK_EQ(visitor.dex_pcs_.size(), thread->GetInstrumentationStack()->size());
if (instrumentation->ShouldNotifyMethodEnterExitEvents()) {
// Create method enter events for all methods currently on the thread's stack. We only do this
// if no debugger is attached to prevent from posting events twice.
auto ssi = visitor.shadow_stack_.rbegin();
for (auto isi = thread->GetInstrumentationStack()->rbegin(),
end = thread->GetInstrumentationStack()->rend(); isi != end; ++isi) {
while (ssi != visitor.shadow_stack_.rend() && (*ssi).frame_id_ < (*isi).frame_id_) {
instrumentation->MethodEnterEvent(thread, (*ssi).this_object_, (*ssi).method_, 0);
++ssi;
}
uint32_t dex_pc = visitor.dex_pcs_.back();
visitor.dex_pcs_.pop_back();
if (!isi->interpreter_entry_ && !isi->method_->IsRuntimeMethod()) {
instrumentation->MethodEnterEvent(thread, (*isi).this_object_, (*isi).method_, dex_pc);
}
}
}
thread->VerifyStack();
}
void Instrumentation::InstrumentThreadStack(Thread* thread) {
instrumentation_stubs_installed_ = true;
InstrumentationInstallStack(thread, this);
}
// Removes the instrumentation exit pc as the return PC for every quick frame.
static void InstrumentationRestoreStack(Thread* thread, void* arg)
REQUIRES(Locks::mutator_lock_) {
Locks::mutator_lock_->AssertExclusiveHeld(Thread::Current());
struct RestoreStackVisitor final : public StackVisitor {
RestoreStackVisitor(Thread* thread_in, uintptr_t instrumentation_exit_pc,
Instrumentation* instrumentation)
: StackVisitor(thread_in, nullptr, kInstrumentationStackWalk),
thread_(thread_in),
instrumentation_exit_pc_(instrumentation_exit_pc),
instrumentation_(instrumentation),
instrumentation_stack_(thread_in->GetInstrumentationStack()),
frames_removed_(0) {}
bool VisitFrame() override REQUIRES_SHARED(Locks::mutator_lock_) {
if (instrumentation_stack_->size() == 0) {
return false; // Stop.
}
ArtMethod* m = GetMethod();
if (GetCurrentQuickFrame() == nullptr) {
if (kVerboseInstrumentation) {
LOG(INFO) << " Ignoring a shadow frame. Frame " << GetFrameId()
<< " Method=" << ArtMethod::PrettyMethod(m);
}
return true; // Ignore shadow frames.
}
if (m == nullptr) {
if (kVerboseInstrumentation) {
LOG(INFO) << " Skipping upcall. Frame " << GetFrameId();
}
return true; // Ignore upcalls.
}
bool removed_stub = false;
// TODO: make this search more efficient?
const size_t frameId = GetFrameId();
for (const InstrumentationStackFrame& instrumentation_frame : *instrumentation_stack_) {
if (instrumentation_frame.frame_id_ == frameId) {
if (kVerboseInstrumentation) {
LOG(INFO) << " Removing exit stub in " << DescribeLocation();
}
if (instrumentation_frame.interpreter_entry_) {
CHECK(m == Runtime::Current()->GetCalleeSaveMethod(CalleeSaveType::kSaveRefsAndArgs));
} else {
CHECK_EQ(m->GetNonObsoleteMethod(),
instrumentation_frame.method_->GetNonObsoleteMethod())
<< ArtMethod::PrettyMethod(m);
}
SetReturnPc(instrumentation_frame.return_pc_);
if (instrumentation_->ShouldNotifyMethodEnterExitEvents() &&
!m->IsRuntimeMethod()) {
// Create the method exit events. As the methods didn't really exit the result is 0.
// We only do this if no debugger is attached to prevent from posting events twice.
instrumentation_->MethodExitEvent(thread_, instrumentation_frame.this_object_, m,
GetDexPc(), JValue());
}
frames_removed_++;
removed_stub = true;
break;
}
}
if (!removed_stub) {
if (kVerboseInstrumentation) {
LOG(INFO) << " No exit stub in " << DescribeLocation();
}
}
return true; // Continue.
}
Thread* const thread_;
const uintptr_t instrumentation_exit_pc_;
Instrumentation* const instrumentation_;
std::deque<instrumentation::InstrumentationStackFrame>* const instrumentation_stack_;
size_t frames_removed_;
};
if (kVerboseInstrumentation) {
std::string thread_name;
thread->GetThreadName(thread_name);
LOG(INFO) << "Removing exit stubs in " << thread_name;
}
std::deque<instrumentation::InstrumentationStackFrame>* stack = thread->GetInstrumentationStack();
if (stack->size() > 0) {
Instrumentation* instrumentation = reinterpret_cast<Instrumentation*>(arg);
uintptr_t instrumentation_exit_pc =
reinterpret_cast<uintptr_t>(GetQuickInstrumentationExitPc());
RestoreStackVisitor visitor(thread, instrumentation_exit_pc, instrumentation);
visitor.WalkStack(true);
CHECK_EQ(visitor.frames_removed_, stack->size());
while (stack->size() > 0) {
stack->pop_front();
}
}
}
static bool HasEvent(Instrumentation::InstrumentationEvent expected, uint32_t events) {
return (events & expected) != 0;
}
static void PotentiallyAddListenerTo(Instrumentation::InstrumentationEvent event,
uint32_t events,
std::list<InstrumentationListener*>& list,
InstrumentationListener* listener,
bool* has_listener)
REQUIRES(Locks::mutator_lock_, !Locks::thread_list_lock_, !Locks::classlinker_classes_lock_) {
Locks::mutator_lock_->AssertExclusiveHeld(Thread::Current());
if (!HasEvent(event, events)) {
return;
}
// If there is a free slot in the list, we insert the listener in that slot.
// Otherwise we add it to the end of the list.
auto it = std::find(list.begin(), list.end(), nullptr);
if (it != list.end()) {
*it = listener;
} else {
list.push_back(listener);
}
Runtime::DoAndMaybeSwitchInterpreter([=](){ *has_listener = true; });
}
void Instrumentation::AddListener(InstrumentationListener* listener, uint32_t events) {
Locks::mutator_lock_->AssertExclusiveHeld(Thread::Current());
PotentiallyAddListenerTo(kMethodEntered,
events,
method_entry_listeners_,
listener,
&have_method_entry_listeners_);
PotentiallyAddListenerTo(kMethodExited,
events,
method_exit_listeners_,
listener,
&have_method_exit_listeners_);
PotentiallyAddListenerTo(kMethodUnwind,
events,
method_unwind_listeners_,
listener,
&have_method_unwind_listeners_);
PotentiallyAddListenerTo(kBranch,
events,
branch_listeners_,
listener,
&have_branch_listeners_);
PotentiallyAddListenerTo(kDexPcMoved,
events,
dex_pc_listeners_,
listener,
&have_dex_pc_listeners_);
PotentiallyAddListenerTo(kFieldRead,
events,
field_read_listeners_,
listener,
&have_field_read_listeners_);
PotentiallyAddListenerTo(kFieldWritten,
events,
field_write_listeners_,
listener,
&have_field_write_listeners_);
PotentiallyAddListenerTo(kExceptionThrown,
events,
exception_thrown_listeners_,
listener,
&have_exception_thrown_listeners_);
PotentiallyAddListenerTo(kWatchedFramePop,
events,
watched_frame_pop_listeners_,
listener,
&have_watched_frame_pop_listeners_);
PotentiallyAddListenerTo(kExceptionHandled,
events,
exception_handled_listeners_,
listener,
&have_exception_handled_listeners_);
UpdateInterpreterHandlerTable();
}
static void PotentiallyRemoveListenerFrom(Instrumentation::InstrumentationEvent event,
uint32_t events,
std::list<InstrumentationListener*>& list,
InstrumentationListener* listener,
bool* has_listener)
REQUIRES(Locks::mutator_lock_, !Locks::thread_list_lock_, !Locks::classlinker_classes_lock_) {
Locks::mutator_lock_->AssertExclusiveHeld(Thread::Current());
if (!HasEvent(event, events)) {
return;
}
auto it = std::find(list.begin(), list.end(), listener);
if (it != list.end()) {
// Just update the entry, do not remove from the list. Removing entries in the list
// is unsafe when mutators are iterating over it.
*it = nullptr;
}
// Check if the list contains any non-null listener, and update 'has_listener'.
for (InstrumentationListener* l : list) {
if (l != nullptr) {
Runtime::DoAndMaybeSwitchInterpreter([=](){ *has_listener = true; });
return;
}
}
Runtime::DoAndMaybeSwitchInterpreter([=](){ *has_listener = false; });
}
void Instrumentation::RemoveListener(InstrumentationListener* listener, uint32_t events) {
Locks::mutator_lock_->AssertExclusiveHeld(Thread::Current());
PotentiallyRemoveListenerFrom(kMethodEntered,
events,
method_entry_listeners_,
listener,
&have_method_entry_listeners_);
PotentiallyRemoveListenerFrom(kMethodExited,
events,
method_exit_listeners_,
listener,
&have_method_exit_listeners_);
PotentiallyRemoveListenerFrom(kMethodUnwind,
events,
method_unwind_listeners_,
listener,
&have_method_unwind_listeners_);
PotentiallyRemoveListenerFrom(kBranch,
events,
branch_listeners_,
listener,
&have_branch_listeners_);
PotentiallyRemoveListenerFrom(kDexPcMoved,
events,
dex_pc_listeners_,
listener,
&have_dex_pc_listeners_);
PotentiallyRemoveListenerFrom(kFieldRead,
events,
field_read_listeners_,
listener,
&have_field_read_listeners_);
PotentiallyRemoveListenerFrom(kFieldWritten,
events,
field_write_listeners_,
listener,
&have_field_write_listeners_);
PotentiallyRemoveListenerFrom(kExceptionThrown,
events,
exception_thrown_listeners_,
listener,
&have_exception_thrown_listeners_);
PotentiallyRemoveListenerFrom(kWatchedFramePop,
events,
watched_frame_pop_listeners_,
listener,
&have_watched_frame_pop_listeners_);
PotentiallyRemoveListenerFrom(kExceptionHandled,
events,
exception_handled_listeners_,
listener,
&have_exception_handled_listeners_);
UpdateInterpreterHandlerTable();
}
Instrumentation::InstrumentationLevel Instrumentation::GetCurrentInstrumentationLevel() const {
if (interpreter_stubs_installed_) {
return InstrumentationLevel::kInstrumentWithInterpreter;
} else if (entry_exit_stubs_installed_) {
return InstrumentationLevel::kInstrumentWithInstrumentationStubs;
} else {
return InstrumentationLevel::kInstrumentNothing;
}
}
bool Instrumentation::RequiresInstrumentationInstallation(InstrumentationLevel new_level) const {
// We need to reinstall instrumentation if we go to a different level.
return GetCurrentInstrumentationLevel() != new_level;
}
void Instrumentation::UpdateInstrumentationLevels(InstrumentationLevel level) {
if (level == InstrumentationLevel::kInstrumentWithInterpreter) {
can_use_instrumentation_trampolines_ = false;
}
if (UNLIKELY(!can_use_instrumentation_trampolines_)) {
for (auto& p : requested_instrumentation_levels_) {
if (p.second == InstrumentationLevel::kInstrumentWithInstrumentationStubs) {
p.second = InstrumentationLevel::kInstrumentWithInterpreter;
}
}
}
}
void Instrumentation::ConfigureStubs(const char* key, InstrumentationLevel desired_level) {
// Store the instrumentation level for this key or remove it.
if (desired_level == InstrumentationLevel::kInstrumentNothing) {
// The client no longer needs instrumentation.
requested_instrumentation_levels_.erase(key);
} else {
// The client needs instrumentation.
requested_instrumentation_levels_.Overwrite(key, desired_level);
}
UpdateInstrumentationLevels(desired_level);
UpdateStubs();
}
void Instrumentation::EnableSingleThreadDeopt() {
// Single-thread deopt only uses interpreter.
can_use_instrumentation_trampolines_ = false;
UpdateInstrumentationLevels(InstrumentationLevel::kInstrumentWithInterpreter);
UpdateStubs();
}
void Instrumentation::UpdateStubs() {
// Look for the highest required instrumentation level.
InstrumentationLevel requested_level = InstrumentationLevel::kInstrumentNothing;
for (const auto& v : requested_instrumentation_levels_) {
requested_level = std::max(requested_level, v.second);
}
DCHECK(can_use_instrumentation_trampolines_ ||
requested_level != InstrumentationLevel::kInstrumentWithInstrumentationStubs)
<< "Use trampolines: " << can_use_instrumentation_trampolines_ << " level "
<< requested_level;
interpret_only_ = (requested_level == InstrumentationLevel::kInstrumentWithInterpreter) ||
forced_interpret_only_;
if (!RequiresInstrumentationInstallation(requested_level)) {
// We're already set.
return;
}
Thread* const self = Thread::Current();
Runtime* runtime = Runtime::Current();
Locks::mutator_lock_->AssertExclusiveHeld(self);
Locks::thread_list_lock_->AssertNotHeld(self);
if (requested_level > InstrumentationLevel::kInstrumentNothing) {
if (requested_level == InstrumentationLevel::kInstrumentWithInterpreter) {
interpreter_stubs_installed_ = true;
entry_exit_stubs_installed_ = true;
} else {
CHECK_EQ(requested_level, InstrumentationLevel::kInstrumentWithInstrumentationStubs);
entry_exit_stubs_installed_ = true;
interpreter_stubs_installed_ = false;
}
InstallStubsClassVisitor visitor(this);
runtime->GetClassLinker()->VisitClasses(&visitor);
instrumentation_stubs_installed_ = true;
MutexLock mu(self, *Locks::thread_list_lock_);
runtime->GetThreadList()->ForEach(InstrumentationInstallStack, this);
} else {
interpreter_stubs_installed_ = false;
entry_exit_stubs_installed_ = false;
InstallStubsClassVisitor visitor(this);
runtime->GetClassLinker()->VisitClasses(&visitor);
// Restore stack only if there is no method currently deoptimized.
bool empty;
{
ReaderMutexLock mu(self, *GetDeoptimizedMethodsLock());
empty = IsDeoptimizedMethodsEmpty(); // Avoid lock violation.
}
if (empty) {
MutexLock mu(self, *Locks::thread_list_lock_);
Runtime::Current()->GetThreadList()->ForEach(InstrumentationRestoreStack, this);
// Only do this after restoring, as walking the stack when restoring will see
// the instrumentation exit pc.
instrumentation_stubs_installed_ = false;
}
}
}
static void ResetQuickAllocEntryPointsForThread(Thread* thread, void* arg ATTRIBUTE_UNUSED) {
thread->ResetQuickAllocEntryPointsForThread(kUseReadBarrier && thread->GetIsGcMarking());
}
void Instrumentation::SetEntrypointsInstrumented(bool instrumented) {
Thread* self = Thread::Current();
Runtime* runtime = Runtime::Current();
Locks::mutator_lock_->AssertNotHeld(self);
Locks::instrument_entrypoints_lock_->AssertHeld(self);
if (runtime->IsStarted()) {
ScopedSuspendAll ssa(__FUNCTION__);
MutexLock mu(self, *Locks::runtime_shutdown_lock_);
SetQuickAllocEntryPointsInstrumented(instrumented);
ResetQuickAllocEntryPoints();
alloc_entrypoints_instrumented_ = instrumented;
} else {
MutexLock mu(self, *Locks::runtime_shutdown_lock_);
SetQuickAllocEntryPointsInstrumented(instrumented);
// Note: ResetQuickAllocEntryPoints only works when the runtime is started. Manually run the
// update for just this thread.
// Note: self may be null. One of those paths is setting instrumentation in the Heap
// constructor for gcstress mode.
if (self != nullptr) {
ResetQuickAllocEntryPointsForThread(self, nullptr);
}
alloc_entrypoints_instrumented_ = instrumented;
}
}
void Instrumentation::InstrumentQuickAllocEntryPoints() {
MutexLock mu(Thread::Current(), *Locks::instrument_entrypoints_lock_);
InstrumentQuickAllocEntryPointsLocked();
}
void Instrumentation::UninstrumentQuickAllocEntryPoints() {
MutexLock mu(Thread::Current(), *Locks::instrument_entrypoints_lock_);
UninstrumentQuickAllocEntryPointsLocked();
}
void Instrumentation::InstrumentQuickAllocEntryPointsLocked() {
Locks::instrument_entrypoints_lock_->AssertHeld(Thread::Current());
if (quick_alloc_entry_points_instrumentation_counter_ == 0) {
SetEntrypointsInstrumented(true);
}
++quick_alloc_entry_points_instrumentation_counter_;
}
void Instrumentation::UninstrumentQuickAllocEntryPointsLocked() {
Locks::instrument_entrypoints_lock_->AssertHeld(Thread::Current());
CHECK_GT(quick_alloc_entry_points_instrumentation_counter_, 0U);
--quick_alloc_entry_points_instrumentation_counter_;
if (quick_alloc_entry_points_instrumentation_counter_ == 0) {
SetEntrypointsInstrumented(false);
}
}
void Instrumentation::ResetQuickAllocEntryPoints() {
Runtime* runtime = Runtime::Current();
if (runtime->IsStarted()) {
MutexLock mu(Thread::Current(), *Locks::thread_list_lock_);
runtime->GetThreadList()->ForEach(ResetQuickAllocEntryPointsForThread, nullptr);
}
}
void Instrumentation::UpdateMethodsCodeImpl(ArtMethod* method, const void* quick_code) {
const void* new_quick_code;
if (LIKELY(!instrumentation_stubs_installed_)) {
new_quick_code = quick_code;
} else {
if ((interpreter_stubs_installed_ || IsDeoptimized(method)) && !method->IsNative()) {
new_quick_code = GetQuickToInterpreterBridge();
} else {
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
if (class_linker->IsQuickResolutionStub(quick_code) ||
class_linker->IsQuickToInterpreterBridge(quick_code)) {
new_quick_code = quick_code;
} else if (entry_exit_stubs_installed_ &&
// We need to make sure not to replace anything that InstallStubsForMethod
// wouldn't. Specifically we cannot stub out Proxy.<init> since subtypes copy the
// implementation directly and this will confuse the instrumentation trampolines.
// TODO We should remove the need for this since it makes it impossible to profile
// Proxy.<init> correctly in all cases.
method != jni::DecodeArtMethod(WellKnownClasses::java_lang_reflect_Proxy_init)) {
new_quick_code = GetQuickInstrumentationEntryPoint();
if (!method->IsNative() && Runtime::Current()->GetJit() != nullptr) {
// Native methods use trampoline entrypoints during interpreter tracing.
DCHECK(!Runtime::Current()->GetJit()->GetCodeCache()->GetGarbageCollectCodeUnsafe());
ProfilingInfo* profiling_info = method->GetProfilingInfo(kRuntimePointerSize);
// Tracing will look at the saved entry point in the profiling info to know the actual
// entrypoint, so we store it here.
if (profiling_info != nullptr) {
profiling_info->SetSavedEntryPoint(quick_code);
}
}
} else {
new_quick_code = quick_code;
}
}
}
UpdateEntrypoints(method, new_quick_code);
}
void Instrumentation::UpdateNativeMethodsCodeToJitCode(ArtMethod* method, const void* quick_code) {
// We don't do any read barrier on `method`'s declaring class in this code, as the JIT might
// enter here on a soon-to-be deleted ArtMethod. Updating the entrypoint is OK though, as
// the ArtMethod is still in memory.
const void* new_quick_code = quick_code;
if (UNLIKELY(instrumentation_stubs_installed_) && entry_exit_stubs_installed_) {
new_quick_code = GetQuickInstrumentationEntryPoint();
}
UpdateEntrypoints(method, new_quick_code);
}
void Instrumentation::UpdateMethodsCode(ArtMethod* method, const void* quick_code) {
DCHECK(method->GetDeclaringClass()->IsResolved());
UpdateMethodsCodeImpl(method, quick_code);
}
void Instrumentation::UpdateMethodsCodeToInterpreterEntryPoint(ArtMethod* method) {
UpdateMethodsCodeImpl(method, GetQuickToInterpreterBridge());
}
void Instrumentation::UpdateMethodsCodeForJavaDebuggable(ArtMethod* method,
const void* quick_code) {
// When the runtime is set to Java debuggable, we may update the entry points of
// all methods of a class to the interpreter bridge. A method's declaring class
// might not be in resolved state yet in that case, so we bypass the DCHECK in
// UpdateMethodsCode.
UpdateMethodsCodeImpl(method, quick_code);
}
bool Instrumentation::AddDeoptimizedMethod(ArtMethod* method) {
if (IsDeoptimizedMethod(method)) {
// Already in the map. Return.
return false;
}
// Not found. Add it.
deoptimized_methods_.insert(method);
return true;
}
bool Instrumentation::IsDeoptimizedMethod(ArtMethod* method) {
return deoptimized_methods_.find(method) != deoptimized_methods_.end();
}
ArtMethod* Instrumentation::BeginDeoptimizedMethod() {
if (deoptimized_methods_.empty()) {
// Empty.
return nullptr;
}
return *deoptimized_methods_.begin();
}
bool Instrumentation::RemoveDeoptimizedMethod(ArtMethod* method) {
auto it = deoptimized_methods_.find(method);
if (it == deoptimized_methods_.end()) {
return false;
}
deoptimized_methods_.erase(it);
return true;
}
bool Instrumentation::IsDeoptimizedMethodsEmpty() const {
return deoptimized_methods_.empty();
}
void Instrumentation::Deoptimize(ArtMethod* method) {
CHECK(!method->IsNative());
CHECK(!method->IsProxyMethod());
CHECK(method->IsInvokable());
Thread* self = Thread::Current();
{
WriterMutexLock mu(self, *GetDeoptimizedMethodsLock());
bool has_not_been_deoptimized = AddDeoptimizedMethod(method);
CHECK(has_not_been_deoptimized) << "Method " << ArtMethod::PrettyMethod(method)
<< " is already deoptimized";
}
if (!interpreter_stubs_installed_) {
UpdateEntrypoints(method, GetQuickInstrumentationEntryPoint());
// Install instrumentation exit stub and instrumentation frames. We may already have installed
// these previously so it will only cover the newly created frames.
instrumentation_stubs_installed_ = true;
MutexLock mu(self, *Locks::thread_list_lock_);
Runtime::Current()->GetThreadList()->ForEach(InstrumentationInstallStack, this);
}
}
void Instrumentation::Undeoptimize(ArtMethod* method) {
CHECK(!method->IsNative());
CHECK(!method->IsProxyMethod());
CHECK(method->IsInvokable());
Thread* self = Thread::Current();
bool empty;
{
WriterMutexLock mu(self, *GetDeoptimizedMethodsLock());
bool found_and_erased = RemoveDeoptimizedMethod(method);
CHECK(found_and_erased) << "Method " << ArtMethod::PrettyMethod(method)
<< " is not deoptimized";
empty = IsDeoptimizedMethodsEmpty();
}
// Restore code and possibly stack only if we did not deoptimize everything.
if (!interpreter_stubs_installed_) {
// Restore its code or resolution trampoline.
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
if (method->IsStatic() && !method->IsConstructor() &&
!method->GetDeclaringClass()->IsInitialized()) {
UpdateEntrypoints(method, GetQuickResolutionStub());
} else {
const void* quick_code = NeedDebugVersionFor(method)
? GetQuickToInterpreterBridge()
: class_linker->GetQuickOatCodeFor(method);
UpdateEntrypoints(method, quick_code);
}
// If there is no deoptimized method left, we can restore the stack of each thread.
if (empty && !entry_exit_stubs_installed_) {
MutexLock mu(self, *Locks::thread_list_lock_);
Runtime::Current()->GetThreadList()->ForEach(InstrumentationRestoreStack, this);
instrumentation_stubs_installed_ = false;
}
}
}
bool Instrumentation::IsDeoptimized(ArtMethod* method) {
DCHECK(method != nullptr);
ReaderMutexLock mu(Thread::Current(), *GetDeoptimizedMethodsLock());
return IsDeoptimizedMethod(method);
}
void Instrumentation::EnableDeoptimization() {
ReaderMutexLock mu(Thread::Current(), *GetDeoptimizedMethodsLock());
CHECK(IsDeoptimizedMethodsEmpty());
CHECK_EQ(deoptimization_enabled_, false);
deoptimization_enabled_ = true;
}
void Instrumentation::DisableDeoptimization(const char* key) {
CHECK_EQ(deoptimization_enabled_, true);
// If we deoptimized everything, undo it.
InstrumentationLevel level = GetCurrentInstrumentationLevel();
if (level == InstrumentationLevel::kInstrumentWithInterpreter) {
UndeoptimizeEverything(key);
}
// Undeoptimized selected methods.
while (true) {
ArtMethod* method;
{
ReaderMutexLock mu(Thread::Current(), *GetDeoptimizedMethodsLock());
if (IsDeoptimizedMethodsEmpty()) {
break;
}
method = BeginDeoptimizedMethod();
CHECK(method != nullptr);
}
Undeoptimize(method);
}
deoptimization_enabled_ = false;
}
// Indicates if instrumentation should notify method enter/exit events to the listeners.
bool Instrumentation::ShouldNotifyMethodEnterExitEvents() const {
if (!HasMethodEntryListeners() && !HasMethodExitListeners()) {
return false;
}
return !deoptimization_enabled_ && !interpreter_stubs_installed_;
}
void Instrumentation::DeoptimizeEverything(const char* key) {
CHECK(deoptimization_enabled_);
ConfigureStubs(key, InstrumentationLevel::kInstrumentWithInterpreter);
}
void Instrumentation::UndeoptimizeEverything(const char* key) {
CHECK(interpreter_stubs_installed_);
CHECK(deoptimization_enabled_);
ConfigureStubs(key, InstrumentationLevel::kInstrumentNothing);
}
void Instrumentation::EnableMethodTracing(const char* key, bool needs_interpreter) {
InstrumentationLevel level;
if (needs_interpreter) {
level = InstrumentationLevel::kInstrumentWithInterpreter;
} else {
level = InstrumentationLevel::kInstrumentWithInstrumentationStubs;
}
ConfigureStubs(key, level);
}
void Instrumentation::DisableMethodTracing(const char* key) {
ConfigureStubs(key, InstrumentationLevel::kInstrumentNothing);
}
const void* Instrumentation::GetCodeForInvoke(ArtMethod* method) const {
// This is called by instrumentation entry only and that should never be getting proxy methods.
DCHECK(!method->IsProxyMethod()) << method->PrettyMethod();
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
if (LIKELY(!instrumentation_stubs_installed_ && !interpreter_stubs_installed_)) {
// In general we just return whatever the method thinks its entrypoint is here. The only
// exception is if it still has the instrumentation entrypoint. That means we are racing another
// thread getting rid of instrumentation which is unexpected but possible. In that case we want
// to wait and try to get it from the oat file or jit.
const void* code = method->GetEntryPointFromQuickCompiledCodePtrSize(kRuntimePointerSize);
DCHECK(code != nullptr);
if (code != GetQuickInstrumentationEntryPoint()) {
return code;
} else if (method->IsNative()) {
return class_linker->GetQuickOatCodeFor(method);
}
// We don't know what it is. Fallthough to try to find the code from the JIT or Oat file.
} else if (method->IsNative()) {
// TODO We could have JIT compiled native entrypoints. It might be worth it to find these.
return class_linker->GetQuickOatCodeFor(method);
} else if (UNLIKELY(interpreter_stubs_installed_)) {
return GetQuickToInterpreterBridge();
}
// Since the method cannot be native due to ifs above we can always fall back to interpreter
// bridge.
const void* result = GetQuickToInterpreterBridge();
if (!NeedDebugVersionFor(method)) {
// If we don't need a debug version we should see what the oat file/class linker has to say.
result = class_linker->GetQuickOatCodeFor(method);
}
// If both those fail try the jit.
if (result == GetQuickToInterpreterBridge()) {
jit::Jit* jit = Runtime::Current()->GetJit();
if (jit != nullptr) {
const void* res = jit->GetCodeCache()->FindCompiledCodeForInstrumentation(method);
if (res != nullptr) {
result = res;
}
}
}
return result;
}
const void* Instrumentation::GetQuickCodeFor(ArtMethod* method, PointerSize pointer_size) const {
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
if (LIKELY(!instrumentation_stubs_installed_)) {
const void* code = method->GetEntryPointFromQuickCompiledCodePtrSize(pointer_size);
DCHECK(code != nullptr);
if (LIKELY(!class_linker->IsQuickResolutionStub(code) &&
!class_linker->IsQuickToInterpreterBridge(code)) &&
!class_linker->IsQuickResolutionStub(code) &&
!class_linker->IsQuickToInterpreterBridge(code)) {
return code;
}
}
return class_linker->GetQuickOatCodeFor(method);
}
void Instrumentation::MethodEnterEventImpl(Thread* thread,
ObjPtr<mirror::Object> this_object,
ArtMethod* method,
uint32_t dex_pc) const {
DCHECK(!method->IsRuntimeMethod());
if (HasMethodEntryListeners()) {
Thread* self = Thread::Current();
StackHandleScope<1> hs(self);
Handle<mirror::Object> thiz(hs.NewHandle(this_object));
for (InstrumentationListener* listener : method_entry_listeners_) {
if (listener != nullptr) {
listener->MethodEntered(thread, thiz, method, dex_pc);
}
}
}
}
void Instrumentation::MethodExitEventImpl(Thread* thread,
ObjPtr<mirror::Object> this_object,
ArtMethod* method,
uint32_t dex_pc,
const JValue& return_value) const {
if (HasMethodExitListeners()) {
Thread* self = Thread::Current();
StackHandleScope<2> hs(self);
Handle<mirror::Object> thiz(hs.NewHandle(this_object));
if (method->GetInterfaceMethodIfProxy(kRuntimePointerSize)
->GetReturnTypePrimitive() != Primitive::kPrimNot) {
for (InstrumentationListener* listener : method_exit_listeners_) {
if (listener != nullptr) {
listener->MethodExited(thread, thiz, method, dex_pc, return_value);
}
}
} else {
Handle<mirror::Object> ret(hs.NewHandle(return_value.GetL()));
for (InstrumentationListener* listener : method_exit_listeners_) {
if (listener != nullptr) {
listener->MethodExited(thread, thiz, method, dex_pc, ret);
}
}
}
}
}
void Instrumentation::MethodUnwindEvent(Thread* thread,
mirror::Object* this_object,
ArtMethod* method,
uint32_t dex_pc) const {
if (HasMethodUnwindListeners()) {
Thread* self = Thread::Current();
StackHandleScope<1> hs(self);
Handle<mirror::Object> thiz(hs.NewHandle(this_object));
for (InstrumentationListener* listener : method_unwind_listeners_) {
if (listener != nullptr) {
listener->MethodUnwind(thread, thiz, method, dex_pc);
}
}
}
}
void Instrumentation::DexPcMovedEventImpl(Thread* thread,
ObjPtr<mirror::Object> this_object,
ArtMethod* method,
uint32_t dex_pc) const {
Thread* self = Thread::Current();
StackHandleScope<1> hs(self);
Handle<mirror::Object> thiz(hs.NewHandle(this_object));
for (InstrumentationListener* listener : dex_pc_listeners_) {
if (listener != nullptr) {
listener->DexPcMoved(thread, thiz, method, dex_pc);
}
}
}
void Instrumentation::BranchImpl(Thread* thread,
ArtMethod* method,
uint32_t dex_pc,
int32_t offset) const {
for (InstrumentationListener* listener : branch_listeners_) {
if (listener != nullptr) {
listener->Branch(thread, method, dex_pc, offset);
}
}
}
void Instrumentation::WatchedFramePopImpl(Thread* thread, const ShadowFrame& frame) const {
for (InstrumentationListener* listener : watched_frame_pop_listeners_) {
if (listener != nullptr) {
listener->WatchedFramePop(thread, frame);
}
}
}
void Instrumentation::FieldReadEventImpl(Thread* thread,
ObjPtr<mirror::Object> this_object,
ArtMethod* method,
uint32_t dex_pc,
ArtField* field) const {
Thread* self = Thread::Current();
StackHandleScope<1> hs(self);
Handle<mirror::Object> thiz(hs.NewHandle(this_object));
for (InstrumentationListener* listener : field_read_listeners_) {
if (listener != nullptr) {
listener->FieldRead(thread, thiz, method, dex_pc, field);
}
}
}
void Instrumentation::FieldWriteEventImpl(Thread* thread,
ObjPtr<mirror::Object> this_object,
ArtMethod* method,
uint32_t dex_pc,
ArtField* field,
const JValue& field_value) const {
Thread* self = Thread::Current();
StackHandleScope<2> hs(self);
Handle<mirror::Object> thiz(hs.NewHandle(this_object));
if (field->IsPrimitiveType()) {
for (InstrumentationListener* listener : field_write_listeners_) {
if (listener != nullptr) {
listener->FieldWritten(thread, thiz, method, dex_pc, field, field_value);
}
}
} else {
Handle<mirror::Object> val(hs.NewHandle(field_value.GetL()));
for (InstrumentationListener* listener : field_write_listeners_) {
if (listener != nullptr) {
listener->FieldWritten(thread, thiz, method, dex_pc, field, val);
}
}
}
}
void Instrumentation::ExceptionThrownEvent(Thread* thread,
mirror::Throwable* exception_object) const {
Thread* self = Thread::Current();
StackHandleScope<1> hs(self);
Handle<mirror::Throwable> h_exception(hs.NewHandle(exception_object));
if (HasExceptionThrownListeners()) {
DCHECK_EQ(thread->GetException(), h_exception.Get());
thread->ClearException();
for (InstrumentationListener* listener : exception_thrown_listeners_) {
if (listener != nullptr) {
listener->ExceptionThrown(thread, h_exception);
}
}
// See b/65049545 for discussion about this behavior.
thread->AssertNoPendingException();
thread->SetException(h_exception.Get());
}
}
void Instrumentation::ExceptionHandledEvent(Thread* thread,
mirror::Throwable* exception_object) const {
Thread* self = Thread::Current();
StackHandleScope<1> hs(self);
Handle<mirror::Throwable> h_exception(hs.NewHandle(exception_object));
if (HasExceptionHandledListeners()) {
// We should have cleared the exception so that callers can detect a new one.
DCHECK(thread->GetException() == nullptr);
for (InstrumentationListener* listener : exception_handled_listeners_) {
if (listener != nullptr) {
listener->ExceptionHandled(thread, h_exception);
}
}
}
}
// Computes a frame ID by ignoring inlined frames.
size_t Instrumentation::ComputeFrameId(Thread* self,
size_t frame_depth,
size_t inlined_frames_before_frame) {
CHECK_GE(frame_depth, inlined_frames_before_frame);
size_t no_inline_depth = frame_depth - inlined_frames_before_frame;
return StackVisitor::ComputeNumFrames(self, kInstrumentationStackWalk) - no_inline_depth;
}
static void CheckStackDepth(Thread* self, const InstrumentationStackFrame& instrumentation_frame,
int delta)
REQUIRES_SHARED(Locks::mutator_lock_) {
size_t frame_id = StackVisitor::ComputeNumFrames(self, kInstrumentationStackWalk) + delta;
if (frame_id != instrumentation_frame.frame_id_) {
LOG(ERROR) << "Expected frame_id=" << frame_id << " but found "
<< instrumentation_frame.frame_id_;
StackVisitor::DescribeStack(self);
CHECK_EQ(frame_id, instrumentation_frame.frame_id_);
}
}
void Instrumentation::PushInstrumentationStackFrame(Thread* self, mirror::Object* this_object,
ArtMethod* method,
uintptr_t lr, bool interpreter_entry) {
DCHECK(!self->IsExceptionPending());
std::deque<instrumentation::InstrumentationStackFrame>* stack = self->GetInstrumentationStack();
if (kVerboseInstrumentation) {
LOG(INFO) << "Entering " << ArtMethod::PrettyMethod(method) << " from PC "
<< reinterpret_cast<void*>(lr);
}
// We send the enter event before pushing the instrumentation frame to make cleanup easier. If the
// event causes an exception we can simply send the unwind event and return.
StackHandleScope<1> hs(self);
Handle<mirror::Object> h_this(hs.NewHandle(this_object));
if (!interpreter_entry) {
MethodEnterEvent(self, h_this.Get(), method, 0);
if (self->IsExceptionPending()) {
MethodUnwindEvent(self, h_this.Get(), method, 0);
return;
}
}
// We have a callee-save frame meaning this value is guaranteed to never be 0.
DCHECK(!self->IsExceptionPending());
size_t frame_id = StackVisitor::ComputeNumFrames(self, kInstrumentationStackWalk);
instrumentation::InstrumentationStackFrame instrumentation_frame(h_this.Get(), method, lr,
frame_id, interpreter_entry);
stack->push_front(instrumentation_frame);
}
DeoptimizationMethodType Instrumentation::GetDeoptimizationMethodType(ArtMethod* method) {
if (method->IsRuntimeMethod()) {
// Certain methods have strict requirement on whether the dex instruction
// should be re-executed upon deoptimization.
if (method == Runtime::Current()->GetCalleeSaveMethod(
CalleeSaveType::kSaveEverythingForClinit)) {
return DeoptimizationMethodType::kKeepDexPc;
}
if (method == Runtime::Current()->GetCalleeSaveMethod(
CalleeSaveType::kSaveEverythingForSuspendCheck)) {
return DeoptimizationMethodType::kKeepDexPc;
}
}
return DeoptimizationMethodType::kDefault;
}
// Try to get the shorty of a runtime method if it's an invocation stub.
static char GetRuntimeMethodShorty(Thread* thread) REQUIRES_SHARED(Locks::mutator_lock_) {
char shorty = 'V';
StackVisitor::WalkStack(
[&shorty](const art::StackVisitor* stack_visitor) REQUIRES_SHARED(Locks::mutator_lock_) {
ArtMethod* m = stack_visitor->GetMethod();
if (m == nullptr || m->IsRuntimeMethod()) {
return true;
}
// The first Java method.
if (m->IsNative()) {
// Use JNI method's shorty for the jni stub.
shorty = m->GetShorty()[0];
} else if (m->IsProxyMethod()) {
// Proxy method just invokes its proxied method via
// art_quick_proxy_invoke_handler.
shorty = m->GetInterfaceMethodIfProxy(kRuntimePointerSize)->GetShorty()[0];
} else {
const Instruction& instr = m->DexInstructions().InstructionAt(stack_visitor->GetDexPc());
if (instr.IsInvoke()) {
auto get_method_index_fn = [](ArtMethod* caller,
const Instruction& inst,
uint32_t dex_pc)
REQUIRES_SHARED(Locks::mutator_lock_) {
switch (inst.Opcode()) {
case Instruction::INVOKE_VIRTUAL_RANGE_QUICK:
case Instruction::INVOKE_VIRTUAL_QUICK: {
uint16_t method_idx = caller->GetIndexFromQuickening(dex_pc);
CHECK_NE(method_idx, DexFile::kDexNoIndex16);
return method_idx;
}
default: {
return static_cast<uint16_t>(inst.VRegB());
}
}
};
uint16_t method_index = get_method_index_fn(m, instr, stack_visitor->GetDexPc());
const DexFile* dex_file = m->GetDexFile();
if (interpreter::IsStringInit(dex_file, method_index)) {
// Invoking string init constructor is turned into invoking
// StringFactory.newStringFromChars() which returns a string.
shorty = 'L';
} else {
shorty = dex_file->GetMethodShorty(method_index)[0];
}
} else {
// It could be that a non-invoke opcode invokes a stub, which in turn
// invokes Java code. In such cases, we should never expect a return
// value from the stub.
}
}
// Stop stack walking since we've seen a Java frame.
return false;
},
thread,
/* context= */ nullptr,
art::StackVisitor::StackWalkKind::kIncludeInlinedFrames);
return shorty;
}
TwoWordReturn Instrumentation::PopInstrumentationStackFrame(Thread* self,
uintptr_t* return_pc,
uint64_t* gpr_result,
uint64_t* fpr_result) {
DCHECK(gpr_result != nullptr);
DCHECK(fpr_result != nullptr);
// Do the pop.
std::deque<instrumentation::InstrumentationStackFrame>* stack = self->GetInstrumentationStack();
CHECK_GT(stack->size(), 0U);
InstrumentationStackFrame instrumentation_frame = stack->front();
stack->pop_front();
// Set return PC and check the sanity of the stack.
*return_pc = instrumentation_frame.return_pc_;
CheckStackDepth(self, instrumentation_frame, 0);
self->VerifyStack();
ArtMethod* method = instrumentation_frame.method_;
uint32_t length;
const PointerSize pointer_size = Runtime::Current()->GetClassLinker()->GetImagePointerSize();
char return_shorty;
// Runtime method does not call into MethodExitEvent() so there should not be
// suspension point below.
ScopedAssertNoThreadSuspension ants(__FUNCTION__, method->IsRuntimeMethod());
if (method->IsRuntimeMethod()) {
if (method != Runtime::Current()->GetCalleeSaveMethod(
CalleeSaveType::kSaveEverythingForClinit)) {
// If the caller is at an invocation point and the runtime method is not
// for clinit, we need to pass return results to the caller.
// We need the correct shorty to decide whether we need to pass the return
// result for deoptimization below.
return_shorty = GetRuntimeMethodShorty(self);
} else {
// Some runtime methods such as allocations, unresolved field getters, etc.
// have return value. We don't need to set return_value since MethodExitEvent()
// below isn't called for runtime methods. Deoptimization doesn't need the
// value either since the dex instruction will be re-executed by the
// interpreter, except these two cases:
// (1) For an invoke, which is handled above to get the correct shorty.
// (2) For MONITOR_ENTER/EXIT, which cannot be re-executed since it's not
// idempotent. However there is no return value for it anyway.
return_shorty = 'V';
}
} else {
return_shorty = method->GetInterfaceMethodIfProxy(pointer_size)->GetShorty(&length)[0];
}
bool is_ref = return_shorty == '[' || return_shorty == 'L';
StackHandleScope<1> hs(self);
MutableHandle<mirror::Object> res(hs.NewHandle<mirror::Object>(nullptr));
JValue return_value;
if (return_shorty == 'V') {
return_value.SetJ(0);
} else if (return_shorty == 'F' || return_shorty == 'D') {
return_value.SetJ(*fpr_result);
} else {
return_value.SetJ(*gpr_result);
}
if (is_ref) {
// Take a handle to the return value so we won't lose it if we suspend.
res.Assign(return_value.GetL());
}
// TODO: improve the dex pc information here, requires knowledge of current PC as opposed to
// return_pc.
uint32_t dex_pc = dex::kDexNoIndex;
mirror::Object* this_object = instrumentation_frame.this_object_;
if (!method->IsRuntimeMethod() && !instrumentation_frame.interpreter_entry_) {
MethodExitEvent(self, this_object, instrumentation_frame.method_, dex_pc, return_value);
}
// Deoptimize if the caller needs to continue execution in the interpreter. Do nothing if we get
// back to an upcall.
NthCallerVisitor visitor(self, 1, true);
visitor.WalkStack(true);
bool deoptimize = (visitor.caller != nullptr) &&
(interpreter_stubs_installed_ || IsDeoptimized(visitor.caller) ||
self->IsForceInterpreter() ||
Dbg::IsForcedInterpreterNeededForUpcall(self, visitor.caller));
if (is_ref) {
// Restore the return value if it's a reference since it might have moved.
*reinterpret_cast<mirror::Object**>(gpr_result) = res.Get();
}
if (deoptimize && Runtime::Current()->IsAsyncDeoptimizeable(*return_pc)) {
if (kVerboseInstrumentation) {
LOG(INFO) << "Deoptimizing "
<< visitor.caller->PrettyMethod()
<< " by returning from "
<< method->PrettyMethod()
<< " with result "
<< std::hex << return_value.GetJ() << std::dec
<< " in "
<< *self;
}
DeoptimizationMethodType deopt_method_type = GetDeoptimizationMethodType(method);
self->PushDeoptimizationContext(return_value,
return_shorty == 'L' || return_shorty == '[',
/* exception= */ nullptr ,
/* from_code= */ false,
deopt_method_type);
return GetTwoWordSuccessValue(*return_pc,
reinterpret_cast<uintptr_t>(GetQuickDeoptimizationEntryPoint()));
} else {
if (deoptimize && !Runtime::Current()->IsAsyncDeoptimizeable(*return_pc)) {
VLOG(deopt) << "Got a deoptimization request on un-deoptimizable " << method->PrettyMethod()
<< " at PC " << reinterpret_cast<void*>(*return_pc);
}
if (kVerboseInstrumentation) {
LOG(INFO) << "Returning from " << method->PrettyMethod()
<< " to PC " << reinterpret_cast<void*>(*return_pc);
}
return GetTwoWordSuccessValue(0, *return_pc);
}
}
uintptr_t Instrumentation::PopFramesForDeoptimization(Thread* self, size_t nframes) const {
std::deque<instrumentation::InstrumentationStackFrame>* stack = self->GetInstrumentationStack();
CHECK_GE(stack->size(), nframes);
if (nframes == 0) {
return 0u;
}
// Only need to send instrumentation events if it's not for deopt (do give the log messages if we
// have verbose-instrumentation anyway though).
if (kVerboseInstrumentation) {
for (size_t i = 0; i < nframes; i++) {
LOG(INFO) << "Popping for deoptimization " << stack->at(i).method_->PrettyMethod();
}
}
// Now that we've sent all the instrumentation events we can actually modify the
// instrumentation-stack. We cannot do this earlier since MethodUnwindEvent can re-enter java and
// do other things that require the instrumentation stack to be in a consistent state with the
// actual stack.
for (size_t i = 0; i < nframes - 1; i++) {
stack->pop_front();
}
uintptr_t return_pc = stack->front().return_pc_;
stack->pop_front();
return return_pc;
}
std::string InstrumentationStackFrame::Dump() const {
std::ostringstream os;
os << "Frame " << frame_id_ << " " << ArtMethod::PrettyMethod(method_) << ":"
<< reinterpret_cast<void*>(return_pc_) << " this=" << reinterpret_cast<void*>(this_object_);
return os.str();
}
} // namespace instrumentation
} // namespace art