/*
* 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.
*/
#define ATRACE_TAG ATRACE_TAG_DALVIK
#include "thread.h"
#include <cutils/trace.h>
#include <pthread.h>
#include <signal.h>
#include <sys/resource.h>
#include <sys/time.h>
#include <algorithm>
#include <bitset>
#include <cerrno>
#include <iostream>
#include <list>
#include <sstream>
#include "arch/context.h"
#include "art_field-inl.h"
#include "art_method-inl.h"
#include "base/bit_utils.h"
#include "base/mutex.h"
#include "base/timing_logger.h"
#include "base/to_str.h"
#include "class_linker-inl.h"
#include "debugger.h"
#include "dex_file-inl.h"
#include "entrypoints/entrypoint_utils.h"
#include "entrypoints/quick/quick_alloc_entrypoints.h"
#include "gc_map.h"
#include "gc/accounting/card_table-inl.h"
#include "gc/allocator/rosalloc.h"
#include "gc/heap.h"
#include "gc/space/space.h"
#include "handle_scope-inl.h"
#include "indirect_reference_table-inl.h"
#include "jni_internal.h"
#include "mirror/class_loader.h"
#include "mirror/class-inl.h"
#include "mirror/object_array-inl.h"
#include "mirror/stack_trace_element.h"
#include "monitor.h"
#include "object_lock.h"
#include "quick_exception_handler.h"
#include "quick/quick_method_frame_info.h"
#include "reflection.h"
#include "runtime.h"
#include "scoped_thread_state_change.h"
#include "ScopedLocalRef.h"
#include "ScopedUtfChars.h"
#include "stack.h"
#include "thread_list.h"
#include "thread-inl.h"
#include "utils.h"
#include "verifier/dex_gc_map.h"
#include "verifier/method_verifier.h"
#include "verify_object-inl.h"
#include "vmap_table.h"
#include "well_known_classes.h"
namespace art {
bool Thread::is_started_ = false;
pthread_key_t Thread::pthread_key_self_;
ConditionVariable* Thread::resume_cond_ = nullptr;
const size_t Thread::kStackOverflowImplicitCheckSize = GetStackOverflowReservedBytes(kRuntimeISA);
static const char* kThreadNameDuringStartup = "<native thread without managed peer>";
void Thread::InitCardTable() {
tlsPtr_.card_table = Runtime::Current()->GetHeap()->GetCardTable()->GetBiasedBegin();
}
static void UnimplementedEntryPoint() {
UNIMPLEMENTED(FATAL);
}
void InitEntryPoints(InterpreterEntryPoints* ipoints, JniEntryPoints* jpoints,
QuickEntryPoints* qpoints);
void Thread::InitTlsEntryPoints() {
// Insert a placeholder so we can easily tell if we call an unimplemented entry point.
uintptr_t* begin = reinterpret_cast<uintptr_t*>(&tlsPtr_.interpreter_entrypoints);
uintptr_t* end = reinterpret_cast<uintptr_t*>(reinterpret_cast<uint8_t*>(&tlsPtr_.quick_entrypoints) +
sizeof(tlsPtr_.quick_entrypoints));
for (uintptr_t* it = begin; it != end; ++it) {
*it = reinterpret_cast<uintptr_t>(UnimplementedEntryPoint);
}
InitEntryPoints(&tlsPtr_.interpreter_entrypoints, &tlsPtr_.jni_entrypoints,
&tlsPtr_.quick_entrypoints);
}
void Thread::InitStringEntryPoints() {
ScopedObjectAccess soa(this);
QuickEntryPoints* qpoints = &tlsPtr_.quick_entrypoints;
qpoints->pNewEmptyString = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newEmptyString));
qpoints->pNewStringFromBytes_B = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newStringFromBytes_B));
qpoints->pNewStringFromBytes_BI = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newStringFromBytes_BI));
qpoints->pNewStringFromBytes_BII = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newStringFromBytes_BII));
qpoints->pNewStringFromBytes_BIII = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newStringFromBytes_BIII));
qpoints->pNewStringFromBytes_BIIString = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newStringFromBytes_BIIString));
qpoints->pNewStringFromBytes_BString = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newStringFromBytes_BString));
qpoints->pNewStringFromBytes_BIICharset = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newStringFromBytes_BIICharset));
qpoints->pNewStringFromBytes_BCharset = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newStringFromBytes_BCharset));
qpoints->pNewStringFromChars_C = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newStringFromChars_C));
qpoints->pNewStringFromChars_CII = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newStringFromChars_CII));
qpoints->pNewStringFromChars_IIC = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newStringFromChars_IIC));
qpoints->pNewStringFromCodePoints = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newStringFromCodePoints));
qpoints->pNewStringFromString = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newStringFromString));
qpoints->pNewStringFromStringBuffer = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newStringFromStringBuffer));
qpoints->pNewStringFromStringBuilder = reinterpret_cast<void(*)()>(
soa.DecodeMethod(WellKnownClasses::java_lang_StringFactory_newStringFromStringBuilder));
}
void Thread::ResetQuickAllocEntryPointsForThread() {
ResetQuickAllocEntryPoints(&tlsPtr_.quick_entrypoints);
}
class DeoptimizationReturnValueRecord {
public:
DeoptimizationReturnValueRecord(const JValue& ret_val,
bool is_reference,
DeoptimizationReturnValueRecord* link)
: ret_val_(ret_val), is_reference_(is_reference), link_(link) {}
JValue GetReturnValue() const { return ret_val_; }
bool IsReference() const { return is_reference_; }
DeoptimizationReturnValueRecord* GetLink() const { return link_; }
mirror::Object** GetGCRoot() {
DCHECK(is_reference_);
return ret_val_.GetGCRoot();
}
private:
JValue ret_val_;
const bool is_reference_;
DeoptimizationReturnValueRecord* const link_;
DISALLOW_COPY_AND_ASSIGN(DeoptimizationReturnValueRecord);
};
class StackedShadowFrameRecord {
public:
StackedShadowFrameRecord(ShadowFrame* shadow_frame,
StackedShadowFrameType type,
StackedShadowFrameRecord* link)
: shadow_frame_(shadow_frame),
type_(type),
link_(link) {}
ShadowFrame* GetShadowFrame() const { return shadow_frame_; }
StackedShadowFrameType GetType() const { return type_; }
StackedShadowFrameRecord* GetLink() const { return link_; }
private:
ShadowFrame* const shadow_frame_;
const StackedShadowFrameType type_;
StackedShadowFrameRecord* const link_;
DISALLOW_COPY_AND_ASSIGN(StackedShadowFrameRecord);
};
void Thread::PushAndClearDeoptimizationReturnValue() {
DeoptimizationReturnValueRecord* record = new DeoptimizationReturnValueRecord(
tls64_.deoptimization_return_value,
tls32_.deoptimization_return_value_is_reference,
tlsPtr_.deoptimization_return_value_stack);
tlsPtr_.deoptimization_return_value_stack = record;
ClearDeoptimizationReturnValue();
}
JValue Thread::PopDeoptimizationReturnValue() {
DeoptimizationReturnValueRecord* record = tlsPtr_.deoptimization_return_value_stack;
DCHECK(record != nullptr);
tlsPtr_.deoptimization_return_value_stack = record->GetLink();
JValue ret_val(record->GetReturnValue());
delete record;
return ret_val;
}
void Thread::PushStackedShadowFrame(ShadowFrame* sf, StackedShadowFrameType type) {
StackedShadowFrameRecord* record = new StackedShadowFrameRecord(
sf, type, tlsPtr_.stacked_shadow_frame_record);
tlsPtr_.stacked_shadow_frame_record = record;
}
ShadowFrame* Thread::PopStackedShadowFrame(StackedShadowFrameType type) {
StackedShadowFrameRecord* record = tlsPtr_.stacked_shadow_frame_record;
DCHECK(record != nullptr);
DCHECK_EQ(record->GetType(), type);
tlsPtr_.stacked_shadow_frame_record = record->GetLink();
ShadowFrame* shadow_frame = record->GetShadowFrame();
delete record;
return shadow_frame;
}
void Thread::InitTid() {
tls32_.tid = ::art::GetTid();
}
void Thread::InitAfterFork() {
// One thread (us) survived the fork, but we have a new tid so we need to
// update the value stashed in this Thread*.
InitTid();
}
void* Thread::CreateCallback(void* arg) {
Thread* self = reinterpret_cast<Thread*>(arg);
Runtime* runtime = Runtime::Current();
if (runtime == nullptr) {
LOG(ERROR) << "Thread attaching to non-existent runtime: " << *self;
return nullptr;
}
{
// TODO: pass self to MutexLock - requires self to equal Thread::Current(), which is only true
// after self->Init().
MutexLock mu(nullptr, *Locks::runtime_shutdown_lock_);
// Check that if we got here we cannot be shutting down (as shutdown should never have started
// while threads are being born).
CHECK(!runtime->IsShuttingDownLocked());
// Note: given that the JNIEnv is created in the parent thread, the only failure point here is
// a mess in InitStackHwm. We do not have a reasonable way to recover from that, so abort
// the runtime in such a case. In case this ever changes, we need to make sure here to
// delete the tmp_jni_env, as we own it at this point.
CHECK(self->Init(runtime->GetThreadList(), runtime->GetJavaVM(), self->tlsPtr_.tmp_jni_env));
self->tlsPtr_.tmp_jni_env = nullptr;
Runtime::Current()->EndThreadBirth();
}
{
ScopedObjectAccess soa(self);
self->InitStringEntryPoints();
// Copy peer into self, deleting global reference when done.
CHECK(self->tlsPtr_.jpeer != nullptr);
self->tlsPtr_.opeer = soa.Decode<mirror::Object*>(self->tlsPtr_.jpeer);
self->GetJniEnv()->DeleteGlobalRef(self->tlsPtr_.jpeer);
self->tlsPtr_.jpeer = nullptr;
self->SetThreadName(self->GetThreadName(soa)->ToModifiedUtf8().c_str());
ArtField* priorityField = soa.DecodeField(WellKnownClasses::java_lang_Thread_priority);
self->SetNativePriority(priorityField->GetInt(self->tlsPtr_.opeer));
Dbg::PostThreadStart(self);
// Invoke the 'run' method of our java.lang.Thread.
mirror::Object* receiver = self->tlsPtr_.opeer;
jmethodID mid = WellKnownClasses::java_lang_Thread_run;
ScopedLocalRef<jobject> ref(soa.Env(), soa.AddLocalReference<jobject>(receiver));
InvokeVirtualOrInterfaceWithJValues(soa, ref.get(), mid, nullptr);
}
// Detach and delete self.
Runtime::Current()->GetThreadList()->Unregister(self);
return nullptr;
}
Thread* Thread::FromManagedThread(const ScopedObjectAccessAlreadyRunnable& soa,
mirror::Object* thread_peer) {
ArtField* f = soa.DecodeField(WellKnownClasses::java_lang_Thread_nativePeer);
Thread* result = reinterpret_cast<Thread*>(static_cast<uintptr_t>(f->GetLong(thread_peer)));
// Sanity check that if we have a result it is either suspended or we hold the thread_list_lock_
// to stop it from going away.
if (kIsDebugBuild) {
MutexLock mu(soa.Self(), *Locks::thread_suspend_count_lock_);
if (result != nullptr && !result->IsSuspended()) {
Locks::thread_list_lock_->AssertHeld(soa.Self());
}
}
return result;
}
Thread* Thread::FromManagedThread(const ScopedObjectAccessAlreadyRunnable& soa,
jobject java_thread) {
return FromManagedThread(soa, soa.Decode<mirror::Object*>(java_thread));
}
static size_t FixStackSize(size_t stack_size) {
// A stack size of zero means "use the default".
if (stack_size == 0) {
stack_size = Runtime::Current()->GetDefaultStackSize();
}
// Dalvik used the bionic pthread default stack size for native threads,
// so include that here to support apps that expect large native stacks.
stack_size += 1 * MB;
// It's not possible to request a stack smaller than the system-defined PTHREAD_STACK_MIN.
if (stack_size < PTHREAD_STACK_MIN) {
stack_size = PTHREAD_STACK_MIN;
}
if (Runtime::Current()->ExplicitStackOverflowChecks()) {
// It's likely that callers are trying to ensure they have at least a certain amount of
// stack space, so we should add our reserved space on top of what they requested, rather
// than implicitly take it away from them.
stack_size += GetStackOverflowReservedBytes(kRuntimeISA);
} else {
// If we are going to use implicit stack checks, allocate space for the protected
// region at the bottom of the stack.
stack_size += Thread::kStackOverflowImplicitCheckSize +
GetStackOverflowReservedBytes(kRuntimeISA);
}
// Some systems require the stack size to be a multiple of the system page size, so round up.
stack_size = RoundUp(stack_size, kPageSize);
return stack_size;
}
// Global variable to prevent the compiler optimizing away the page reads for the stack.
uint8_t dont_optimize_this;
// Install a protected region in the stack. This is used to trigger a SIGSEGV if a stack
// overflow is detected. It is located right below the stack_begin_.
//
// There is a little complexity here that deserves a special mention. On some
// architectures, the stack created using a VM_GROWSDOWN flag
// to prevent memory being allocated when it's not needed. This flag makes the
// kernel only allocate memory for the stack by growing down in memory. Because we
// want to put an mprotected region far away from that at the stack top, we need
// to make sure the pages for the stack are mapped in before we call mprotect. We do
// this by reading every page from the stack bottom (highest address) to the stack top.
// We then madvise this away.
void Thread::InstallImplicitProtection() {
uint8_t* pregion = tlsPtr_.stack_begin - kStackOverflowProtectedSize;
uint8_t* stack_himem = tlsPtr_.stack_end;
uint8_t* stack_top = reinterpret_cast<uint8_t*>(reinterpret_cast<uintptr_t>(&stack_himem) &
~(kPageSize - 1)); // Page containing current top of stack.
// First remove the protection on the protected region as will want to read and
// write it. This may fail (on the first attempt when the stack is not mapped)
// but we ignore that.
UnprotectStack();
// Map in the stack. This must be done by reading from the
// current stack pointer downwards as the stack may be mapped using VM_GROWSDOWN
// in the kernel. Any access more than a page below the current SP might cause
// a segv.
// Read every page from the high address to the low.
for (uint8_t* p = stack_top; p >= pregion; p -= kPageSize) {
dont_optimize_this = *p;
}
VLOG(threads) << "installing stack protected region at " << std::hex <<
static_cast<void*>(pregion) << " to " <<
static_cast<void*>(pregion + kStackOverflowProtectedSize - 1);
// Protect the bottom of the stack to prevent read/write to it.
ProtectStack();
// Tell the kernel that we won't be needing these pages any more.
// NB. madvise will probably write zeroes into the memory (on linux it does).
uint32_t unwanted_size = stack_top - pregion - kPageSize;
madvise(pregion, unwanted_size, MADV_DONTNEED);
}
void Thread::CreateNativeThread(JNIEnv* env, jobject java_peer, size_t stack_size, bool is_daemon) {
CHECK(java_peer != nullptr);
Thread* self = static_cast<JNIEnvExt*>(env)->self;
Runtime* runtime = Runtime::Current();
// Atomically start the birth of the thread ensuring the runtime isn't shutting down.
bool thread_start_during_shutdown = false;
{
MutexLock mu(self, *Locks::runtime_shutdown_lock_);
if (runtime->IsShuttingDownLocked()) {
thread_start_during_shutdown = true;
} else {
runtime->StartThreadBirth();
}
}
if (thread_start_during_shutdown) {
ScopedLocalRef<jclass> error_class(env, env->FindClass("java/lang/InternalError"));
env->ThrowNew(error_class.get(), "Thread starting during runtime shutdown");
return;
}
Thread* child_thread = new Thread(is_daemon);
// Use global JNI ref to hold peer live while child thread starts.
child_thread->tlsPtr_.jpeer = env->NewGlobalRef(java_peer);
stack_size = FixStackSize(stack_size);
// Thread.start is synchronized, so we know that nativePeer is 0, and know that we're not racing to
// assign it.
env->SetLongField(java_peer, WellKnownClasses::java_lang_Thread_nativePeer,
reinterpret_cast<jlong>(child_thread));
// Try to allocate a JNIEnvExt for the thread. We do this here as we might be out of memory and
// do not have a good way to report this on the child's side.
std::unique_ptr<JNIEnvExt> child_jni_env_ext(
JNIEnvExt::Create(child_thread, Runtime::Current()->GetJavaVM()));
int pthread_create_result = 0;
if (child_jni_env_ext.get() != nullptr) {
pthread_t new_pthread;
pthread_attr_t attr;
child_thread->tlsPtr_.tmp_jni_env = child_jni_env_ext.get();
CHECK_PTHREAD_CALL(pthread_attr_init, (&attr), "new thread");
CHECK_PTHREAD_CALL(pthread_attr_setdetachstate, (&attr, PTHREAD_CREATE_DETACHED),
"PTHREAD_CREATE_DETACHED");
CHECK_PTHREAD_CALL(pthread_attr_setstacksize, (&attr, stack_size), stack_size);
pthread_create_result = pthread_create(&new_pthread,
&attr,
Thread::CreateCallback,
child_thread);
CHECK_PTHREAD_CALL(pthread_attr_destroy, (&attr), "new thread");
if (pthread_create_result == 0) {
// pthread_create started the new thread. The child is now responsible for managing the
// JNIEnvExt we created.
// Note: we can't check for tmp_jni_env == nullptr, as that would require synchronization
// between the threads.
child_jni_env_ext.release();
return;
}
}
// Either JNIEnvExt::Create or pthread_create(3) failed, so clean up.
{
MutexLock mu(self, *Locks::runtime_shutdown_lock_);
runtime->EndThreadBirth();
}
// Manually delete the global reference since Thread::Init will not have been run.
env->DeleteGlobalRef(child_thread->tlsPtr_.jpeer);
child_thread->tlsPtr_.jpeer = nullptr;
delete child_thread;
child_thread = nullptr;
// TODO: remove from thread group?
env->SetLongField(java_peer, WellKnownClasses::java_lang_Thread_nativePeer, 0);
{
std::string msg(child_jni_env_ext.get() == nullptr ?
"Could not allocate JNI Env" :
StringPrintf("pthread_create (%s stack) failed: %s",
PrettySize(stack_size).c_str(), strerror(pthread_create_result)));
ScopedObjectAccess soa(env);
soa.Self()->ThrowOutOfMemoryError(msg.c_str());
}
}
bool Thread::Init(ThreadList* thread_list, JavaVMExt* java_vm, JNIEnvExt* jni_env_ext) {
// This function does all the initialization that must be run by the native thread it applies to.
// (When we create a new thread from managed code, we allocate the Thread* in Thread::Create so
// we can handshake with the corresponding native thread when it's ready.) Check this native
// thread hasn't been through here already...
CHECK(Thread::Current() == nullptr);
// Set pthread_self_ ahead of pthread_setspecific, that makes Thread::Current function, this
// avoids pthread_self_ ever being invalid when discovered from Thread::Current().
tlsPtr_.pthread_self = pthread_self();
CHECK(is_started_);
SetUpAlternateSignalStack();
if (!InitStackHwm()) {
return false;
}
InitCpu();
InitTlsEntryPoints();
RemoveSuspendTrigger();
InitCardTable();
InitTid();
CHECK_PTHREAD_CALL(pthread_setspecific, (Thread::pthread_key_self_, this), "attach self");
DCHECK_EQ(Thread::Current(), this);
tls32_.thin_lock_thread_id = thread_list->AllocThreadId(this);
if (jni_env_ext != nullptr) {
DCHECK_EQ(jni_env_ext->vm, java_vm);
DCHECK_EQ(jni_env_ext->self, this);
tlsPtr_.jni_env = jni_env_ext;
} else {
tlsPtr_.jni_env = JNIEnvExt::Create(this, java_vm);
if (tlsPtr_.jni_env == nullptr) {
return false;
}
}
thread_list->Register(this);
return true;
}
Thread* Thread::Attach(const char* thread_name, bool as_daemon, jobject thread_group,
bool create_peer) {
Runtime* runtime = Runtime::Current();
if (runtime == nullptr) {
LOG(ERROR) << "Thread attaching to non-existent runtime: " << thread_name;
return nullptr;
}
Thread* self;
{
MutexLock mu(nullptr, *Locks::runtime_shutdown_lock_);
if (runtime->IsShuttingDownLocked()) {
LOG(ERROR) << "Thread attaching while runtime is shutting down: " << thread_name;
return nullptr;
} else {
Runtime::Current()->StartThreadBirth();
self = new Thread(as_daemon);
bool init_success = self->Init(runtime->GetThreadList(), runtime->GetJavaVM());
Runtime::Current()->EndThreadBirth();
if (!init_success) {
delete self;
return nullptr;
}
}
}
self->InitStringEntryPoints();
CHECK_NE(self->GetState(), kRunnable);
self->SetState(kNative);
// If we're the main thread, ClassLinker won't be created until after we're attached,
// so that thread needs a two-stage attach. Regular threads don't need this hack.
// In the compiler, all threads need this hack, because no-one's going to be getting
// a native peer!
if (create_peer) {
self->CreatePeer(thread_name, as_daemon, thread_group);
if (self->IsExceptionPending()) {
// We cannot keep the exception around, as we're deleting self. Try to be helpful and log it.
{
ScopedObjectAccess soa(self);
LOG(ERROR) << "Exception creating thread peer:";
LOG(ERROR) << self->GetException()->Dump();
self->ClearException();
}
runtime->GetThreadList()->Unregister(self);
// Unregister deletes self, no need to do this here.
return nullptr;
}
} else {
// These aren't necessary, but they improve diagnostics for unit tests & command-line tools.
if (thread_name != nullptr) {
self->tlsPtr_.name->assign(thread_name);
::art::SetThreadName(thread_name);
} else if (self->GetJniEnv()->check_jni) {
LOG(WARNING) << *Thread::Current() << " attached without supplying a name";
}
}
{
ScopedObjectAccess soa(self);
Dbg::PostThreadStart(self);
}
return self;
}
void Thread::CreatePeer(const char* name, bool as_daemon, jobject thread_group) {
Runtime* runtime = Runtime::Current();
CHECK(runtime->IsStarted());
JNIEnv* env = tlsPtr_.jni_env;
if (thread_group == nullptr) {
thread_group = runtime->GetMainThreadGroup();
}
ScopedLocalRef<jobject> thread_name(env, env->NewStringUTF(name));
// Add missing null check in case of OOM b/18297817
if (name != nullptr && thread_name.get() == nullptr) {
CHECK(IsExceptionPending());
return;
}
jint thread_priority = GetNativePriority();
jboolean thread_is_daemon = as_daemon;
ScopedLocalRef<jobject> peer(env, env->AllocObject(WellKnownClasses::java_lang_Thread));
if (peer.get() == nullptr) {
CHECK(IsExceptionPending());
return;
}
{
ScopedObjectAccess soa(this);
tlsPtr_.opeer = soa.Decode<mirror::Object*>(peer.get());
}
env->CallNonvirtualVoidMethod(peer.get(),
WellKnownClasses::java_lang_Thread,
WellKnownClasses::java_lang_Thread_init,
thread_group, thread_name.get(), thread_priority, thread_is_daemon);
if (IsExceptionPending()) {
return;
}
Thread* self = this;
DCHECK_EQ(self, Thread::Current());
env->SetLongField(peer.get(), WellKnownClasses::java_lang_Thread_nativePeer,
reinterpret_cast<jlong>(self));
ScopedObjectAccess soa(self);
StackHandleScope<1> hs(self);
MutableHandle<mirror::String> peer_thread_name(hs.NewHandle(GetThreadName(soa)));
if (peer_thread_name.Get() == nullptr) {
// The Thread constructor should have set the Thread.name to a
// non-null value. However, because we can run without code
// available (in the compiler, in tests), we manually assign the
// fields the constructor should have set.
if (runtime->IsActiveTransaction()) {
InitPeer<true>(soa, thread_is_daemon, thread_group, thread_name.get(), thread_priority);
} else {
InitPeer<false>(soa, thread_is_daemon, thread_group, thread_name.get(), thread_priority);
}
peer_thread_name.Assign(GetThreadName(soa));
}
// 'thread_name' may have been null, so don't trust 'peer_thread_name' to be non-null.
if (peer_thread_name.Get() != nullptr) {
SetThreadName(peer_thread_name->ToModifiedUtf8().c_str());
}
}
template<bool kTransactionActive>
void Thread::InitPeer(ScopedObjectAccess& soa, jboolean thread_is_daemon, jobject thread_group,
jobject thread_name, jint thread_priority) {
soa.DecodeField(WellKnownClasses::java_lang_Thread_daemon)->
SetBoolean<kTransactionActive>(tlsPtr_.opeer, thread_is_daemon);
soa.DecodeField(WellKnownClasses::java_lang_Thread_group)->
SetObject<kTransactionActive>(tlsPtr_.opeer, soa.Decode<mirror::Object*>(thread_group));
soa.DecodeField(WellKnownClasses::java_lang_Thread_name)->
SetObject<kTransactionActive>(tlsPtr_.opeer, soa.Decode<mirror::Object*>(thread_name));
soa.DecodeField(WellKnownClasses::java_lang_Thread_priority)->
SetInt<kTransactionActive>(tlsPtr_.opeer, thread_priority);
}
void Thread::SetThreadName(const char* name) {
tlsPtr_.name->assign(name);
::art::SetThreadName(name);
Dbg::DdmSendThreadNotification(this, CHUNK_TYPE("THNM"));
}
bool Thread::InitStackHwm() {
void* read_stack_base;
size_t read_stack_size;
size_t read_guard_size;
GetThreadStack(tlsPtr_.pthread_self, &read_stack_base, &read_stack_size, &read_guard_size);
tlsPtr_.stack_begin = reinterpret_cast<uint8_t*>(read_stack_base);
tlsPtr_.stack_size = read_stack_size;
// The minimum stack size we can cope with is the overflow reserved bytes (typically
// 8K) + the protected region size (4K) + another page (4K). Typically this will
// be 8+4+4 = 16K. The thread won't be able to do much with this stack even the GC takes
// between 8K and 12K.
uint32_t min_stack = GetStackOverflowReservedBytes(kRuntimeISA) + kStackOverflowProtectedSize
+ 4 * KB;
if (read_stack_size <= min_stack) {
// Note, as we know the stack is small, avoid operations that could use a lot of stack.
LogMessage::LogLineLowStack(__PRETTY_FUNCTION__, __LINE__, ERROR,
"Attempt to attach a thread with a too-small stack");
return false;
}
// This is included in the SIGQUIT output, but it's useful here for thread debugging.
VLOG(threads) << StringPrintf("Native stack is at %p (%s with %s guard)",
read_stack_base,
PrettySize(read_stack_size).c_str(),
PrettySize(read_guard_size).c_str());
// Set stack_end_ to the bottom of the stack saving space of stack overflows
Runtime* runtime = Runtime::Current();
bool implicit_stack_check = !runtime->ExplicitStackOverflowChecks() && !runtime->IsAotCompiler();
ResetDefaultStackEnd();
// Install the protected region if we are doing implicit overflow checks.
if (implicit_stack_check) {
// The thread might have protected region at the bottom. We need
// to install our own region so we need to move the limits
// of the stack to make room for it.
tlsPtr_.stack_begin += read_guard_size + kStackOverflowProtectedSize;
tlsPtr_.stack_end += read_guard_size + kStackOverflowProtectedSize;
tlsPtr_.stack_size -= read_guard_size;
InstallImplicitProtection();
}
// Sanity check.
int stack_variable;
CHECK_GT(&stack_variable, reinterpret_cast<void*>(tlsPtr_.stack_end));
return true;
}
void Thread::ShortDump(std::ostream& os) const {
os << "Thread[";
if (GetThreadId() != 0) {
// If we're in kStarting, we won't have a thin lock id or tid yet.
os << GetThreadId()
<< ",tid=" << GetTid() << ',';
}
os << GetState()
<< ",Thread*=" << this
<< ",peer=" << tlsPtr_.opeer
<< ",\"" << (tlsPtr_.name != nullptr ? *tlsPtr_.name : "null") << "\""
<< "]";
}
void Thread::Dump(std::ostream& os) const {
DumpState(os);
DumpStack(os);
}
mirror::String* Thread::GetThreadName(const ScopedObjectAccessAlreadyRunnable& soa) const {
ArtField* f = soa.DecodeField(WellKnownClasses::java_lang_Thread_name);
return (tlsPtr_.opeer != nullptr) ?
reinterpret_cast<mirror::String*>(f->GetObject(tlsPtr_.opeer)) : nullptr;
}
void Thread::GetThreadName(std::string& name) const {
name.assign(*tlsPtr_.name);
}
uint64_t Thread::GetCpuMicroTime() const {
#if defined(__linux__)
clockid_t cpu_clock_id;
pthread_getcpuclockid(tlsPtr_.pthread_self, &cpu_clock_id);
timespec now;
clock_gettime(cpu_clock_id, &now);
return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000) + now.tv_nsec / UINT64_C(1000);
#else // __APPLE__
UNIMPLEMENTED(WARNING);
return -1;
#endif
}
// Attempt to rectify locks so that we dump thread list with required locks before exiting.
static void UnsafeLogFatalForSuspendCount(Thread* self, Thread* thread) NO_THREAD_SAFETY_ANALYSIS {
LOG(ERROR) << *thread << " suspend count already zero.";
Locks::thread_suspend_count_lock_->Unlock(self);
if (!Locks::mutator_lock_->IsSharedHeld(self)) {
Locks::mutator_lock_->SharedTryLock(self);
if (!Locks::mutator_lock_->IsSharedHeld(self)) {
LOG(WARNING) << "Dumping thread list without holding mutator_lock_";
}
}
if (!Locks::thread_list_lock_->IsExclusiveHeld(self)) {
Locks::thread_list_lock_->TryLock(self);
if (!Locks::thread_list_lock_->IsExclusiveHeld(self)) {
LOG(WARNING) << "Dumping thread list without holding thread_list_lock_";
}
}
std::ostringstream ss;
Runtime::Current()->GetThreadList()->Dump(ss);
LOG(FATAL) << ss.str();
}
void Thread::ModifySuspendCount(Thread* self, int delta, bool for_debugger) {
if (kIsDebugBuild) {
DCHECK(delta == -1 || delta == +1 || delta == -tls32_.debug_suspend_count)
<< delta << " " << tls32_.debug_suspend_count << " " << this;
DCHECK_GE(tls32_.suspend_count, tls32_.debug_suspend_count) << this;
Locks::thread_suspend_count_lock_->AssertHeld(self);
if (this != self && !IsSuspended()) {
Locks::thread_list_lock_->AssertHeld(self);
}
}
if (UNLIKELY(delta < 0 && tls32_.suspend_count <= 0)) {
UnsafeLogFatalForSuspendCount(self, this);
return;
}
tls32_.suspend_count += delta;
if (for_debugger) {
tls32_.debug_suspend_count += delta;
}
if (tls32_.suspend_count == 0) {
AtomicClearFlag(kSuspendRequest);
} else {
AtomicSetFlag(kSuspendRequest);
TriggerSuspend();
}
}
void Thread::RunCheckpointFunction() {
Closure *checkpoints[kMaxCheckpoints];
// Grab the suspend_count lock and copy the current set of
// checkpoints. Then clear the list and the flag. The RequestCheckpoint
// function will also grab this lock so we prevent a race between setting
// the kCheckpointRequest flag and clearing it.
{
MutexLock mu(this, *Locks::thread_suspend_count_lock_);
for (uint32_t i = 0; i < kMaxCheckpoints; ++i) {
checkpoints[i] = tlsPtr_.checkpoint_functions[i];
tlsPtr_.checkpoint_functions[i] = nullptr;
}
AtomicClearFlag(kCheckpointRequest);
}
// Outside the lock, run all the checkpoint functions that
// we collected.
bool found_checkpoint = false;
for (uint32_t i = 0; i < kMaxCheckpoints; ++i) {
if (checkpoints[i] != nullptr) {
ATRACE_BEGIN("Checkpoint function");
checkpoints[i]->Run(this);
ATRACE_END();
found_checkpoint = true;
}
}
CHECK(found_checkpoint);
}
bool Thread::RequestCheckpoint(Closure* function) {
union StateAndFlags old_state_and_flags;
old_state_and_flags.as_int = tls32_.state_and_flags.as_int;
if (old_state_and_flags.as_struct.state != kRunnable) {
return false; // Fail, thread is suspended and so can't run a checkpoint.
}
uint32_t available_checkpoint = kMaxCheckpoints;
for (uint32_t i = 0 ; i < kMaxCheckpoints; ++i) {
if (tlsPtr_.checkpoint_functions[i] == nullptr) {
available_checkpoint = i;
break;
}
}
if (available_checkpoint == kMaxCheckpoints) {
// No checkpoint functions available, we can't run a checkpoint
return false;
}
tlsPtr_.checkpoint_functions[available_checkpoint] = function;
// Checkpoint function installed now install flag bit.
// We must be runnable to request a checkpoint.
DCHECK_EQ(old_state_and_flags.as_struct.state, kRunnable);
union StateAndFlags new_state_and_flags;
new_state_and_flags.as_int = old_state_and_flags.as_int;
new_state_and_flags.as_struct.flags |= kCheckpointRequest;
bool success = tls32_.state_and_flags.as_atomic_int.CompareExchangeStrongSequentiallyConsistent(
old_state_and_flags.as_int, new_state_and_flags.as_int);
if (UNLIKELY(!success)) {
// The thread changed state before the checkpoint was installed.
CHECK_EQ(tlsPtr_.checkpoint_functions[available_checkpoint], function);
tlsPtr_.checkpoint_functions[available_checkpoint] = nullptr;
} else {
CHECK_EQ(ReadFlag(kCheckpointRequest), true);
TriggerSuspend();
}
return success;
}
Closure* Thread::GetFlipFunction() {
Atomic<Closure*>* atomic_func = reinterpret_cast<Atomic<Closure*>*>(&tlsPtr_.flip_function);
Closure* func;
do {
func = atomic_func->LoadRelaxed();
if (func == nullptr) {
return nullptr;
}
} while (!atomic_func->CompareExchangeWeakSequentiallyConsistent(func, nullptr));
DCHECK(func != nullptr);
return func;
}
void Thread::SetFlipFunction(Closure* function) {
CHECK(function != nullptr);
Atomic<Closure*>* atomic_func = reinterpret_cast<Atomic<Closure*>*>(&tlsPtr_.flip_function);
atomic_func->StoreSequentiallyConsistent(function);
}
void Thread::FullSuspendCheck() {
VLOG(threads) << this << " self-suspending";
ATRACE_BEGIN("Full suspend check");
// Make thread appear suspended to other threads, release mutator_lock_.
tls32_.suspended_at_suspend_check = true;
TransitionFromRunnableToSuspended(kSuspended);
// Transition back to runnable noting requests to suspend, re-acquire share on mutator_lock_.
TransitionFromSuspendedToRunnable();
tls32_.suspended_at_suspend_check = false;
ATRACE_END();
VLOG(threads) << this << " self-reviving";
}
void Thread::DumpState(std::ostream& os, const Thread* thread, pid_t tid) {
std::string group_name;
int priority;
bool is_daemon = false;
Thread* self = Thread::Current();
// If flip_function is not null, it means we have run a checkpoint
// before the thread wakes up to execute the flip function and the
// thread roots haven't been forwarded. So the following access to
// the roots (opeer or methods in the frames) would be bad. Run it
// here. TODO: clean up.
if (thread != nullptr) {
ScopedObjectAccessUnchecked soa(self);
Thread* this_thread = const_cast<Thread*>(thread);
Closure* flip_func = this_thread->GetFlipFunction();
if (flip_func != nullptr) {
flip_func->Run(this_thread);
}
}
// Don't do this if we are aborting since the GC may have all the threads suspended. This will
// cause ScopedObjectAccessUnchecked to deadlock.
if (gAborting == 0 && self != nullptr && thread != nullptr && thread->tlsPtr_.opeer != nullptr) {
ScopedObjectAccessUnchecked soa(self);
priority = soa.DecodeField(WellKnownClasses::java_lang_Thread_priority)
->GetInt(thread->tlsPtr_.opeer);
is_daemon = soa.DecodeField(WellKnownClasses::java_lang_Thread_daemon)
->GetBoolean(thread->tlsPtr_.opeer);
mirror::Object* thread_group =
soa.DecodeField(WellKnownClasses::java_lang_Thread_group)->GetObject(thread->tlsPtr_.opeer);
if (thread_group != nullptr) {
ArtField* group_name_field =
soa.DecodeField(WellKnownClasses::java_lang_ThreadGroup_name);
mirror::String* group_name_string =
reinterpret_cast<mirror::String*>(group_name_field->GetObject(thread_group));
group_name = (group_name_string != nullptr) ? group_name_string->ToModifiedUtf8() : "<null>";
}
} else {
priority = GetNativePriority();
}
std::string scheduler_group_name(GetSchedulerGroupName(tid));
if (scheduler_group_name.empty()) {
scheduler_group_name = "default";
}
if (thread != nullptr) {
os << '"' << *thread->tlsPtr_.name << '"';
if (is_daemon) {
os << " daemon";
}
os << " prio=" << priority
<< " tid=" << thread->GetThreadId()
<< " " << thread->GetState();
if (thread->IsStillStarting()) {
os << " (still starting up)";
}
os << "\n";
} else {
os << '"' << ::art::GetThreadName(tid) << '"'
<< " prio=" << priority
<< " (not attached)\n";
}
if (thread != nullptr) {
MutexLock mu(self, *Locks::thread_suspend_count_lock_);
os << " | group=\"" << group_name << "\""
<< " sCount=" << thread->tls32_.suspend_count
<< " dsCount=" << thread->tls32_.debug_suspend_count
<< " obj=" << reinterpret_cast<void*>(thread->tlsPtr_.opeer)
<< " self=" << reinterpret_cast<const void*>(thread) << "\n";
}
os << " | sysTid=" << tid
<< " nice=" << getpriority(PRIO_PROCESS, tid)
<< " cgrp=" << scheduler_group_name;
if (thread != nullptr) {
int policy;
sched_param sp;
CHECK_PTHREAD_CALL(pthread_getschedparam, (thread->tlsPtr_.pthread_self, &policy, &sp),
__FUNCTION__);
os << " sched=" << policy << "/" << sp.sched_priority
<< " handle=" << reinterpret_cast<void*>(thread->tlsPtr_.pthread_self);
}
os << "\n";
// Grab the scheduler stats for this thread.
std::string scheduler_stats;
if (ReadFileToString(StringPrintf("/proc/self/task/%d/schedstat", tid), &scheduler_stats)) {
scheduler_stats.resize(scheduler_stats.size() - 1); // Lose the trailing '\n'.
} else {
scheduler_stats = "0 0 0";
}
char native_thread_state = '?';
int utime = 0;
int stime = 0;
int task_cpu = 0;
GetTaskStats(tid, &native_thread_state, &utime, &stime, &task_cpu);
os << " | state=" << native_thread_state
<< " schedstat=( " << scheduler_stats << " )"
<< " utm=" << utime
<< " stm=" << stime
<< " core=" << task_cpu
<< " HZ=" << sysconf(_SC_CLK_TCK) << "\n";
if (thread != nullptr) {
os << " | stack=" << reinterpret_cast<void*>(thread->tlsPtr_.stack_begin) << "-"
<< reinterpret_cast<void*>(thread->tlsPtr_.stack_end) << " stackSize="
<< PrettySize(thread->tlsPtr_.stack_size) << "\n";
// Dump the held mutexes.
os << " | held mutexes=";
for (size_t i = 0; i < kLockLevelCount; ++i) {
if (i != kMonitorLock) {
BaseMutex* mutex = thread->GetHeldMutex(static_cast<LockLevel>(i));
if (mutex != nullptr) {
os << " \"" << mutex->GetName() << "\"";
if (mutex->IsReaderWriterMutex()) {
ReaderWriterMutex* rw_mutex = down_cast<ReaderWriterMutex*>(mutex);
if (rw_mutex->GetExclusiveOwnerTid() == static_cast<uint64_t>(tid)) {
os << "(exclusive held)";
} else {
os << "(shared held)";
}
}
}
}
}
os << "\n";
}
}
void Thread::DumpState(std::ostream& os) const {
Thread::DumpState(os, this, GetTid());
}
struct StackDumpVisitor : public StackVisitor {
StackDumpVisitor(std::ostream& os_in, Thread* thread_in, Context* context, bool can_allocate_in)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
: StackVisitor(thread_in, context, StackVisitor::StackWalkKind::kIncludeInlinedFrames),
os(os_in),
thread(thread_in),
can_allocate(can_allocate_in),
last_method(nullptr),
last_line_number(0),
repetition_count(0),
frame_count(0) {}
virtual ~StackDumpVisitor() {
if (frame_count == 0) {
os << " (no managed stack frames)\n";
}
}
bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
ArtMethod* m = GetMethod();
if (m->IsRuntimeMethod()) {
return true;
}
m = m->GetInterfaceMethodIfProxy(sizeof(void*));
const int kMaxRepetition = 3;
mirror::Class* c = m->GetDeclaringClass();
mirror::DexCache* dex_cache = c->GetDexCache();
int line_number = -1;
if (dex_cache != nullptr) { // be tolerant of bad input
const DexFile& dex_file = *dex_cache->GetDexFile();
line_number = dex_file.GetLineNumFromPC(m, GetDexPc(false));
}
if (line_number == last_line_number && last_method == m) {
++repetition_count;
} else {
if (repetition_count >= kMaxRepetition) {
os << " ... repeated " << (repetition_count - kMaxRepetition) << " times\n";
}
repetition_count = 0;
last_line_number = line_number;
last_method = m;
}
if (repetition_count < kMaxRepetition) {
os << " at " << PrettyMethod(m, false);
if (m->IsNative()) {
os << "(Native method)";
} else {
const char* source_file(m->GetDeclaringClassSourceFile());
os << "(" << (source_file != nullptr ? source_file : "unavailable")
<< ":" << line_number << ")";
}
os << "\n";
if (frame_count == 0) {
Monitor::DescribeWait(os, thread);
}
if (can_allocate) {
// Visit locks, but do not abort on errors. This would trigger a nested abort.
Monitor::VisitLocks(this, DumpLockedObject, &os, false);
}
}
++frame_count;
return true;
}
static void DumpLockedObject(mirror::Object* o, void* context)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
std::ostream& os = *reinterpret_cast<std::ostream*>(context);
os << " - locked ";
if (o == nullptr) {
os << "an unknown object";
} else {
if ((o->GetLockWord(false).GetState() == LockWord::kThinLocked) &&
Locks::mutator_lock_->IsExclusiveHeld(Thread::Current())) {
// Getting the identity hashcode here would result in lock inflation and suspension of the
// current thread, which isn't safe if this is the only runnable thread.
os << StringPrintf("<@addr=0x%" PRIxPTR "> (a %s)", reinterpret_cast<intptr_t>(o),
PrettyTypeOf(o).c_str());
} else {
// IdentityHashCode can cause thread suspension, which would invalidate o if it moved. So
// we get the pretty type beofre we call IdentityHashCode.
const std::string pretty_type(PrettyTypeOf(o));
os << StringPrintf("<0x%08x> (a %s)", o->IdentityHashCode(), pretty_type.c_str());
}
}
os << "\n";
}
std::ostream& os;
const Thread* thread;
const bool can_allocate;
ArtMethod* last_method;
int last_line_number;
int repetition_count;
int frame_count;
};
static bool ShouldShowNativeStack(const Thread* thread)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
ThreadState state = thread->GetState();
// In native code somewhere in the VM (one of the kWaitingFor* states)? That's interesting.
if (state > kWaiting && state < kStarting) {
return true;
}
// In an Object.wait variant or Thread.sleep? That's not interesting.
if (state == kTimedWaiting || state == kSleeping || state == kWaiting) {
return false;
}
// Threads with no managed stack frames should be shown.
const ManagedStack* managed_stack = thread->GetManagedStack();
if (managed_stack == nullptr || (managed_stack->GetTopQuickFrame() == nullptr &&
managed_stack->GetTopShadowFrame() == nullptr)) {
return true;
}
// In some other native method? That's interesting.
// We don't just check kNative because native methods will be in state kSuspended if they're
// calling back into the VM, or kBlocked if they're blocked on a monitor, or one of the
// thread-startup states if it's early enough in their life cycle (http://b/7432159).
ArtMethod* current_method = thread->GetCurrentMethod(nullptr);
return current_method != nullptr && current_method->IsNative();
}
void Thread::DumpJavaStack(std::ostream& os) const {
// If flip_function is not null, it means we have run a checkpoint
// before the thread wakes up to execute the flip function and the
// thread roots haven't been forwarded. So the following access to
// the roots (locks or methods in the frames) would be bad. Run it
// here. TODO: clean up.
{
Thread* this_thread = const_cast<Thread*>(this);
Closure* flip_func = this_thread->GetFlipFunction();
if (flip_func != nullptr) {
flip_func->Run(this_thread);
}
}
// Dumping the Java stack involves the verifier for locks. The verifier operates under the
// assumption that there is no exception pending on entry. Thus, stash any pending exception.
// Thread::Current() instead of this in case a thread is dumping the stack of another suspended
// thread.
StackHandleScope<1> scope(Thread::Current());
Handle<mirror::Throwable> exc;
bool have_exception = false;
if (IsExceptionPending()) {
exc = scope.NewHandle(GetException());
const_cast<Thread*>(this)->ClearException();
have_exception = true;
}
std::unique_ptr<Context> context(Context::Create());
StackDumpVisitor dumper(os, const_cast<Thread*>(this), context.get(),
!tls32_.throwing_OutOfMemoryError);
dumper.WalkStack();
if (have_exception) {
const_cast<Thread*>(this)->SetException(exc.Get());
}
}
void Thread::DumpStack(std::ostream& os) const {
// TODO: we call this code when dying but may not have suspended the thread ourself. The
// IsSuspended check is therefore racy with the use for dumping (normally we inhibit
// the race with the thread_suspend_count_lock_).
bool dump_for_abort = (gAborting > 0);
bool safe_to_dump = (this == Thread::Current() || IsSuspended());
if (!kIsDebugBuild) {
// We always want to dump the stack for an abort, however, there is no point dumping another
// thread's stack in debug builds where we'll hit the not suspended check in the stack walk.
safe_to_dump = (safe_to_dump || dump_for_abort);
}
if (safe_to_dump) {
// If we're currently in native code, dump that stack before dumping the managed stack.
if (dump_for_abort || ShouldShowNativeStack(this)) {
DumpKernelStack(os, GetTid(), " kernel: ", false);
DumpNativeStack(os, GetTid(), " native: ", GetCurrentMethod(nullptr, !dump_for_abort));
}
DumpJavaStack(os);
} else {
os << "Not able to dump stack of thread that isn't suspended";
}
}
void Thread::ThreadExitCallback(void* arg) {
Thread* self = reinterpret_cast<Thread*>(arg);
if (self->tls32_.thread_exit_check_count == 0) {
LOG(WARNING) << "Native thread exiting without having called DetachCurrentThread (maybe it's "
"going to use a pthread_key_create destructor?): " << *self;
CHECK(is_started_);
CHECK_PTHREAD_CALL(pthread_setspecific, (Thread::pthread_key_self_, self), "reattach self");
self->tls32_.thread_exit_check_count = 1;
} else {
LOG(FATAL) << "Native thread exited without calling DetachCurrentThread: " << *self;
}
}
void Thread::Startup() {
CHECK(!is_started_);
is_started_ = true;
{
// MutexLock to keep annotalysis happy.
//
// Note we use null for the thread because Thread::Current can
// return garbage since (is_started_ == true) and
// Thread::pthread_key_self_ is not yet initialized.
// This was seen on glibc.
MutexLock mu(nullptr, *Locks::thread_suspend_count_lock_);
resume_cond_ = new ConditionVariable("Thread resumption condition variable",
*Locks::thread_suspend_count_lock_);
}
// Allocate a TLS slot.
CHECK_PTHREAD_CALL(pthread_key_create, (&Thread::pthread_key_self_, Thread::ThreadExitCallback),
"self key");
// Double-check the TLS slot allocation.
if (pthread_getspecific(pthread_key_self_) != nullptr) {
LOG(FATAL) << "Newly-created pthread TLS slot is not nullptr";
}
}
void Thread::FinishStartup() {
Runtime* runtime = Runtime::Current();
CHECK(runtime->IsStarted());
// Finish attaching the main thread.
ScopedObjectAccess soa(Thread::Current());
Thread::Current()->CreatePeer("main", false, runtime->GetMainThreadGroup());
Thread::Current()->AssertNoPendingException();
Runtime::Current()->GetClassLinker()->RunRootClinits();
}
void Thread::Shutdown() {
CHECK(is_started_);
is_started_ = false;
CHECK_PTHREAD_CALL(pthread_key_delete, (Thread::pthread_key_self_), "self key");
MutexLock mu(Thread::Current(), *Locks::thread_suspend_count_lock_);
if (resume_cond_ != nullptr) {
delete resume_cond_;
resume_cond_ = nullptr;
}
}
Thread::Thread(bool daemon) : tls32_(daemon), wait_monitor_(nullptr), interrupted_(false) {
wait_mutex_ = new Mutex("a thread wait mutex");
wait_cond_ = new ConditionVariable("a thread wait condition variable", *wait_mutex_);
tlsPtr_.instrumentation_stack = new std::deque<instrumentation::InstrumentationStackFrame>;
tlsPtr_.name = new std::string(kThreadNameDuringStartup);
tlsPtr_.nested_signal_state = static_cast<jmp_buf*>(malloc(sizeof(jmp_buf)));
CHECK_EQ((sizeof(Thread) % 4), 0U) << sizeof(Thread);
tls32_.state_and_flags.as_struct.flags = 0;
tls32_.state_and_flags.as_struct.state = kNative;
memset(&tlsPtr_.held_mutexes[0], 0, sizeof(tlsPtr_.held_mutexes));
std::fill(tlsPtr_.rosalloc_runs,
tlsPtr_.rosalloc_runs + kNumRosAllocThreadLocalSizeBrackets,
gc::allocator::RosAlloc::GetDedicatedFullRun());
for (uint32_t i = 0; i < kMaxCheckpoints; ++i) {
tlsPtr_.checkpoint_functions[i] = nullptr;
}
tlsPtr_.flip_function = nullptr;
tls32_.suspended_at_suspend_check = false;
}
bool Thread::IsStillStarting() const {
// You might think you can check whether the state is kStarting, but for much of thread startup,
// the thread is in kNative; it might also be in kVmWait.
// You might think you can check whether the peer is null, but the peer is actually created and
// assigned fairly early on, and needs to be.
// It turns out that the last thing to change is the thread name; that's a good proxy for "has
// this thread _ever_ entered kRunnable".
return (tlsPtr_.jpeer == nullptr && tlsPtr_.opeer == nullptr) ||
(*tlsPtr_.name == kThreadNameDuringStartup);
}
void Thread::AssertPendingException() const {
CHECK(IsExceptionPending()) << "Pending exception expected.";
}
void Thread::AssertPendingOOMException() const {
AssertPendingException();
auto* e = GetException();
CHECK_EQ(e->GetClass(), DecodeJObject(WellKnownClasses::java_lang_OutOfMemoryError)->AsClass())
<< e->Dump();
}
void Thread::AssertNoPendingException() const {
if (UNLIKELY(IsExceptionPending())) {
ScopedObjectAccess soa(Thread::Current());
mirror::Throwable* exception = GetException();
LOG(FATAL) << "No pending exception expected: " << exception->Dump();
}
}
void Thread::AssertNoPendingExceptionForNewException(const char* msg) const {
if (UNLIKELY(IsExceptionPending())) {
ScopedObjectAccess soa(Thread::Current());
mirror::Throwable* exception = GetException();
LOG(FATAL) << "Throwing new exception '" << msg << "' with unexpected pending exception: "
<< exception->Dump();
}
}
class MonitorExitVisitor : public SingleRootVisitor {
public:
explicit MonitorExitVisitor(Thread* self) : self_(self) { }
// NO_THREAD_SAFETY_ANALYSIS due to MonitorExit.
void VisitRoot(mirror::Object* entered_monitor, const RootInfo& info ATTRIBUTE_UNUSED)
OVERRIDE NO_THREAD_SAFETY_ANALYSIS {
if (self_->HoldsLock(entered_monitor)) {
LOG(WARNING) << "Calling MonitorExit on object "
<< entered_monitor << " (" << PrettyTypeOf(entered_monitor) << ")"
<< " left locked by native thread "
<< *Thread::Current() << " which is detaching";
entered_monitor->MonitorExit(self_);
}
}
private:
Thread* const self_;
};
void Thread::Destroy() {
Thread* self = this;
DCHECK_EQ(self, Thread::Current());
if (tlsPtr_.jni_env != nullptr) {
{
ScopedObjectAccess soa(self);
MonitorExitVisitor visitor(self);
// On thread detach, all monitors entered with JNI MonitorEnter are automatically exited.
tlsPtr_.jni_env->monitors.VisitRoots(&visitor, RootInfo(kRootVMInternal));
}
// Release locally held global references which releasing may require the mutator lock.
if (tlsPtr_.jpeer != nullptr) {
// If pthread_create fails we don't have a jni env here.
tlsPtr_.jni_env->DeleteGlobalRef(tlsPtr_.jpeer);
tlsPtr_.jpeer = nullptr;
}
if (tlsPtr_.class_loader_override != nullptr) {
tlsPtr_.jni_env->DeleteGlobalRef(tlsPtr_.class_loader_override);
tlsPtr_.class_loader_override = nullptr;
}
}
if (tlsPtr_.opeer != nullptr) {
ScopedObjectAccess soa(self);
// We may need to call user-supplied managed code, do this before final clean-up.
HandleUncaughtExceptions(soa);
RemoveFromThreadGroup(soa);
// this.nativePeer = 0;
if (Runtime::Current()->IsActiveTransaction()) {
soa.DecodeField(WellKnownClasses::java_lang_Thread_nativePeer)
->SetLong<true>(tlsPtr_.opeer, 0);
} else {
soa.DecodeField(WellKnownClasses::java_lang_Thread_nativePeer)
->SetLong<false>(tlsPtr_.opeer, 0);
}
Dbg::PostThreadDeath(self);
// Thread.join() is implemented as an Object.wait() on the Thread.lock object. Signal anyone
// who is waiting.
mirror::Object* lock =
soa.DecodeField(WellKnownClasses::java_lang_Thread_lock)->GetObject(tlsPtr_.opeer);
// (This conditional is only needed for tests, where Thread.lock won't have been set.)
if (lock != nullptr) {
StackHandleScope<1> hs(self);
Handle<mirror::Object> h_obj(hs.NewHandle(lock));
ObjectLock<mirror::Object> locker(self, h_obj);
locker.NotifyAll();
}
tlsPtr_.opeer = nullptr;
}
{
ScopedObjectAccess soa(self);
Runtime::Current()->GetHeap()->RevokeThreadLocalBuffers(this);
}
}
Thread::~Thread() {
CHECK(tlsPtr_.class_loader_override == nullptr);
CHECK(tlsPtr_.jpeer == nullptr);
CHECK(tlsPtr_.opeer == nullptr);
bool initialized = (tlsPtr_.jni_env != nullptr); // Did Thread::Init run?
if (initialized) {
delete tlsPtr_.jni_env;
tlsPtr_.jni_env = nullptr;
}
CHECK_NE(GetState(), kRunnable);
CHECK_NE(ReadFlag(kCheckpointRequest), true);
CHECK(tlsPtr_.checkpoint_functions[0] == nullptr);
CHECK(tlsPtr_.checkpoint_functions[1] == nullptr);
CHECK(tlsPtr_.checkpoint_functions[2] == nullptr);
CHECK(tlsPtr_.flip_function == nullptr);
CHECK_EQ(tls32_.suspended_at_suspend_check, false);
// We may be deleting a still born thread.
SetStateUnsafe(kTerminated);
delete wait_cond_;
delete wait_mutex_;
if (tlsPtr_.long_jump_context != nullptr) {
delete tlsPtr_.long_jump_context;
}
if (initialized) {
CleanupCpu();
}
if (tlsPtr_.single_step_control != nullptr) {
delete tlsPtr_.single_step_control;
}
delete tlsPtr_.instrumentation_stack;
delete tlsPtr_.name;
delete tlsPtr_.stack_trace_sample;
free(tlsPtr_.nested_signal_state);
Runtime::Current()->GetHeap()->AssertThreadLocalBuffersAreRevoked(this);
TearDownAlternateSignalStack();
}
void Thread::HandleUncaughtExceptions(ScopedObjectAccess& soa) {
if (!IsExceptionPending()) {
return;
}
ScopedLocalRef<jobject> peer(tlsPtr_.jni_env, soa.AddLocalReference<jobject>(tlsPtr_.opeer));
ScopedThreadStateChange tsc(this, kNative);
// Get and clear the exception.
ScopedLocalRef<jthrowable> exception(tlsPtr_.jni_env, tlsPtr_.jni_env->ExceptionOccurred());
tlsPtr_.jni_env->ExceptionClear();
// If the thread has its own handler, use that.
ScopedLocalRef<jobject> handler(tlsPtr_.jni_env,
tlsPtr_.jni_env->GetObjectField(peer.get(),
WellKnownClasses::java_lang_Thread_uncaughtHandler));
if (handler.get() == nullptr) {
// Otherwise use the thread group's default handler.
handler.reset(tlsPtr_.jni_env->GetObjectField(peer.get(),
WellKnownClasses::java_lang_Thread_group));
}
// Call the handler.
tlsPtr_.jni_env->CallVoidMethod(handler.get(),
WellKnownClasses::java_lang_Thread__UncaughtExceptionHandler_uncaughtException,
peer.get(), exception.get());
// If the handler threw, clear that exception too.
tlsPtr_.jni_env->ExceptionClear();
}
void Thread::RemoveFromThreadGroup(ScopedObjectAccess& soa) {
// this.group.removeThread(this);
// group can be null if we're in the compiler or a test.
mirror::Object* ogroup = soa.DecodeField(WellKnownClasses::java_lang_Thread_group)
->GetObject(tlsPtr_.opeer);
if (ogroup != nullptr) {
ScopedLocalRef<jobject> group(soa.Env(), soa.AddLocalReference<jobject>(ogroup));
ScopedLocalRef<jobject> peer(soa.Env(), soa.AddLocalReference<jobject>(tlsPtr_.opeer));
ScopedThreadStateChange tsc(soa.Self(), kNative);
tlsPtr_.jni_env->CallVoidMethod(group.get(),
WellKnownClasses::java_lang_ThreadGroup_removeThread,
peer.get());
}
}
size_t Thread::NumHandleReferences() {
size_t count = 0;
for (HandleScope* cur = tlsPtr_.top_handle_scope; cur != nullptr; cur = cur->GetLink()) {
count += cur->NumberOfReferences();
}
return count;
}
bool Thread::HandleScopeContains(jobject obj) const {
StackReference<mirror::Object>* hs_entry =
reinterpret_cast<StackReference<mirror::Object>*>(obj);
for (HandleScope* cur = tlsPtr_.top_handle_scope; cur!= nullptr; cur = cur->GetLink()) {
if (cur->Contains(hs_entry)) {
return true;
}
}
// JNI code invoked from portable code uses shadow frames rather than the handle scope.
return tlsPtr_.managed_stack.ShadowFramesContain(hs_entry);
}
void Thread::HandleScopeVisitRoots(RootVisitor* visitor, uint32_t thread_id) {
BufferedRootVisitor<kDefaultBufferedRootCount> buffered_visitor(
visitor, RootInfo(kRootNativeStack, thread_id));
for (HandleScope* cur = tlsPtr_.top_handle_scope; cur; cur = cur->GetLink()) {
for (size_t j = 0, count = cur->NumberOfReferences(); j < count; ++j) {
// GetReference returns a pointer to the stack reference within the handle scope. If this
// needs to be updated, it will be done by the root visitor.
buffered_visitor.VisitRootIfNonNull(cur->GetHandle(j).GetReference());
}
}
}
mirror::Object* Thread::DecodeJObject(jobject obj) const {
if (obj == nullptr) {
return nullptr;
}
IndirectRef ref = reinterpret_cast<IndirectRef>(obj);
IndirectRefKind kind = GetIndirectRefKind(ref);
mirror::Object* result;
bool expect_null = false;
// The "kinds" below are sorted by the frequency we expect to encounter them.
if (kind == kLocal) {
IndirectReferenceTable& locals = tlsPtr_.jni_env->locals;
// Local references do not need a read barrier.
result = locals.Get<kWithoutReadBarrier>(ref);
} else if (kind == kHandleScopeOrInvalid) {
// TODO: make stack indirect reference table lookup more efficient.
// Check if this is a local reference in the handle scope.
if (LIKELY(HandleScopeContains(obj))) {
// Read from handle scope.
result = reinterpret_cast<StackReference<mirror::Object>*>(obj)->AsMirrorPtr();
VerifyObject(result);
} else {
tlsPtr_.jni_env->vm->JniAbortF(nullptr, "use of invalid jobject %p", obj);
expect_null = true;
result = nullptr;
}
} else if (kind == kGlobal) {
result = tlsPtr_.jni_env->vm->DecodeGlobal(const_cast<Thread*>(this), ref);
} else {
DCHECK_EQ(kind, kWeakGlobal);
result = tlsPtr_.jni_env->vm->DecodeWeakGlobal(const_cast<Thread*>(this), ref);
if (Runtime::Current()->IsClearedJniWeakGlobal(result)) {
// This is a special case where it's okay to return null.
expect_null = true;
result = nullptr;
}
}
if (UNLIKELY(!expect_null && result == nullptr)) {
tlsPtr_.jni_env->vm->JniAbortF(nullptr, "use of deleted %s %p",
ToStr<IndirectRefKind>(kind).c_str(), obj);
}
return result;
}
// Implements java.lang.Thread.interrupted.
bool Thread::Interrupted() {
MutexLock mu(Thread::Current(), *wait_mutex_);
bool interrupted = IsInterruptedLocked();
SetInterruptedLocked(false);
return interrupted;
}
// Implements java.lang.Thread.isInterrupted.
bool Thread::IsInterrupted() {
MutexLock mu(Thread::Current(), *wait_mutex_);
return IsInterruptedLocked();
}
void Thread::Interrupt(Thread* self) {
MutexLock mu(self, *wait_mutex_);
if (interrupted_) {
return;
}
interrupted_ = true;
NotifyLocked(self);
}
void Thread::Notify() {
Thread* self = Thread::Current();
MutexLock mu(self, *wait_mutex_);
NotifyLocked(self);
}
void Thread::NotifyLocked(Thread* self) {
if (wait_monitor_ != nullptr) {
wait_cond_->Signal(self);
}
}
void Thread::SetClassLoaderOverride(jobject class_loader_override) {
if (tlsPtr_.class_loader_override != nullptr) {
GetJniEnv()->DeleteGlobalRef(tlsPtr_.class_loader_override);
}
tlsPtr_.class_loader_override = GetJniEnv()->NewGlobalRef(class_loader_override);
}
class CountStackDepthVisitor : public StackVisitor {
public:
explicit CountStackDepthVisitor(Thread* thread)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
: StackVisitor(thread, nullptr, StackVisitor::StackWalkKind::kIncludeInlinedFrames),
depth_(0), skip_depth_(0), skipping_(true) {}
bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
// We want to skip frames up to and including the exception's constructor.
// Note we also skip the frame if it doesn't have a method (namely the callee
// save frame)
ArtMethod* m = GetMethod();
if (skipping_ && !m->IsRuntimeMethod() &&
!mirror::Throwable::GetJavaLangThrowable()->IsAssignableFrom(m->GetDeclaringClass())) {
skipping_ = false;
}
if (!skipping_) {
if (!m->IsRuntimeMethod()) { // Ignore runtime frames (in particular callee save).
++depth_;
}
} else {
++skip_depth_;
}
return true;
}
int GetDepth() const {
return depth_;
}
int GetSkipDepth() const {
return skip_depth_;
}
private:
uint32_t depth_;
uint32_t skip_depth_;
bool skipping_;
};
template<bool kTransactionActive>
class BuildInternalStackTraceVisitor : public StackVisitor {
public:
explicit BuildInternalStackTraceVisitor(Thread* self, Thread* thread, int skip_depth)
: StackVisitor(thread, nullptr, StackVisitor::StackWalkKind::kIncludeInlinedFrames),
self_(self),
skip_depth_(skip_depth),
count_(0),
trace_(nullptr),
pointer_size_(Runtime::Current()->GetClassLinker()->GetImagePointerSize()) {}
bool Init(int depth)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
// Allocate method trace with format [method pointers][pcs].
auto* cl = Runtime::Current()->GetClassLinker();
trace_ = cl->AllocPointerArray(self_, depth * 2);
if (trace_ == nullptr) {
self_->AssertPendingOOMException();
return false;
}
// If We are called from native, use non-transactional mode.
const char* last_no_suspend_cause =
self_->StartAssertNoThreadSuspension("Building internal stack trace");
CHECK(last_no_suspend_cause == nullptr) << last_no_suspend_cause;
return true;
}
virtual ~BuildInternalStackTraceVisitor() {
if (trace_ != nullptr) {
self_->EndAssertNoThreadSuspension(nullptr);
}
}
bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
if (trace_ == nullptr) {
return true; // We're probably trying to fillInStackTrace for an OutOfMemoryError.
}
if (skip_depth_ > 0) {
skip_depth_--;
return true;
}
ArtMethod* m = GetMethod();
if (m->IsRuntimeMethod()) {
return true; // Ignore runtime frames (in particular callee save).
}
trace_->SetElementPtrSize<kTransactionActive>(
count_, m, pointer_size_);
trace_->SetElementPtrSize<kTransactionActive>(
trace_->GetLength() / 2 + count_, m->IsProxyMethod() ? DexFile::kDexNoIndex : GetDexPc(),
pointer_size_);
++count_;
return true;
}
mirror::PointerArray* GetInternalStackTrace() const {
return trace_;
}
private:
Thread* const self_;
// How many more frames to skip.
int32_t skip_depth_;
// Current position down stack trace.
uint32_t count_;
// An array of the methods on the stack, the last entries are the dex PCs.
mirror::PointerArray* trace_;
// For cross compilation.
size_t pointer_size_;
};
template<bool kTransactionActive>
jobject Thread::CreateInternalStackTrace(const ScopedObjectAccessAlreadyRunnable& soa) const {
// Compute depth of stack
CountStackDepthVisitor count_visitor(const_cast<Thread*>(this));
count_visitor.WalkStack();
int32_t depth = count_visitor.GetDepth();
int32_t skip_depth = count_visitor.GetSkipDepth();
// Build internal stack trace.
BuildInternalStackTraceVisitor<kTransactionActive> build_trace_visitor(soa.Self(),
const_cast<Thread*>(this),
skip_depth);
if (!build_trace_visitor.Init(depth)) {
return nullptr; // Allocation failed.
}
build_trace_visitor.WalkStack();
mirror::PointerArray* trace = build_trace_visitor.GetInternalStackTrace();
if (kIsDebugBuild) {
// Second half is dex PCs.
for (uint32_t i = 0; i < static_cast<uint32_t>(trace->GetLength() / 2); ++i) {
auto* method = trace->GetElementPtrSize<ArtMethod*>(
i, Runtime::Current()->GetClassLinker()->GetImagePointerSize());
CHECK(method != nullptr);
}
}
return soa.AddLocalReference<jobject>(trace);
}
template jobject Thread::CreateInternalStackTrace<false>(
const ScopedObjectAccessAlreadyRunnable& soa) const;
template jobject Thread::CreateInternalStackTrace<true>(
const ScopedObjectAccessAlreadyRunnable& soa) const;
bool Thread::IsExceptionThrownByCurrentMethod(mirror::Throwable* exception) const {
CountStackDepthVisitor count_visitor(const_cast<Thread*>(this));
count_visitor.WalkStack();
return count_visitor.GetDepth() == exception->GetStackDepth();
}
jobjectArray Thread::InternalStackTraceToStackTraceElementArray(
const ScopedObjectAccessAlreadyRunnable& soa, jobject internal, jobjectArray output_array,
int* stack_depth) {
// Decode the internal stack trace into the depth, method trace and PC trace
int32_t depth = soa.Decode<mirror::PointerArray*>(internal)->GetLength() / 2;
auto* cl = Runtime::Current()->GetClassLinker();
jobjectArray result;
if (output_array != nullptr) {
// Reuse the array we were given.
result = output_array;
// ...adjusting the number of frames we'll write to not exceed the array length.
const int32_t traces_length =
soa.Decode<mirror::ObjectArray<mirror::StackTraceElement>*>(result)->GetLength();
depth = std::min(depth, traces_length);
} else {
// Create java_trace array and place in local reference table
mirror::ObjectArray<mirror::StackTraceElement>* java_traces =
cl->AllocStackTraceElementArray(soa.Self(), depth);
if (java_traces == nullptr) {
return nullptr;
}
result = soa.AddLocalReference<jobjectArray>(java_traces);
}
if (stack_depth != nullptr) {
*stack_depth = depth;
}
for (int32_t i = 0; i < depth; ++i) {
auto* method_trace = soa.Decode<mirror::PointerArray*>(internal);
// Prepare parameters for StackTraceElement(String cls, String method, String file, int line)
ArtMethod* method = method_trace->GetElementPtrSize<ArtMethod*>(i, sizeof(void*));
uint32_t dex_pc = method_trace->GetElementPtrSize<uint32_t>(
i + method_trace->GetLength() / 2, sizeof(void*));
int32_t line_number;
StackHandleScope<3> hs(soa.Self());
auto class_name_object(hs.NewHandle<mirror::String>(nullptr));
auto source_name_object(hs.NewHandle<mirror::String>(nullptr));
if (method->IsProxyMethod()) {
line_number = -1;
class_name_object.Assign(method->GetDeclaringClass()->GetName());
// source_name_object intentionally left null for proxy methods
} else {
line_number = method->GetLineNumFromDexPC(dex_pc);
// Allocate element, potentially triggering GC
// TODO: reuse class_name_object via Class::name_?
const char* descriptor = method->GetDeclaringClassDescriptor();
CHECK(descriptor != nullptr);
std::string class_name(PrettyDescriptor(descriptor));
class_name_object.Assign(
mirror::String::AllocFromModifiedUtf8(soa.Self(), class_name.c_str()));
if (class_name_object.Get() == nullptr) {
soa.Self()->AssertPendingOOMException();
return nullptr;
}
const char* source_file = method->GetDeclaringClassSourceFile();
if (source_file != nullptr) {
source_name_object.Assign(mirror::String::AllocFromModifiedUtf8(soa.Self(), source_file));
if (source_name_object.Get() == nullptr) {
soa.Self()->AssertPendingOOMException();
return nullptr;
}
}
}
const char* method_name = method->GetInterfaceMethodIfProxy(sizeof(void*))->GetName();
CHECK(method_name != nullptr);
Handle<mirror::String> method_name_object(
hs.NewHandle(mirror::String::AllocFromModifiedUtf8(soa.Self(), method_name)));
if (method_name_object.Get() == nullptr) {
return nullptr;
}
mirror::StackTraceElement* obj = mirror::StackTraceElement::Alloc(
soa.Self(), class_name_object, method_name_object, source_name_object, line_number);
if (obj == nullptr) {
return nullptr;
}
// We are called from native: use non-transactional mode.
soa.Decode<mirror::ObjectArray<mirror::StackTraceElement>*>(result)->Set<false>(i, obj);
}
return result;
}
void Thread::ThrowNewExceptionF(const char* exception_class_descriptor, const char* fmt, ...) {
va_list args;
va_start(args, fmt);
ThrowNewExceptionV(exception_class_descriptor, fmt, args);
va_end(args);
}
void Thread::ThrowNewExceptionV(const char* exception_class_descriptor,
const char* fmt, va_list ap) {
std::string msg;
StringAppendV(&msg, fmt, ap);
ThrowNewException(exception_class_descriptor, msg.c_str());
}
void Thread::ThrowNewException(const char* exception_class_descriptor,
const char* msg) {
// Callers should either clear or call ThrowNewWrappedException.
AssertNoPendingExceptionForNewException(msg);
ThrowNewWrappedException(exception_class_descriptor, msg);
}
static mirror::ClassLoader* GetCurrentClassLoader(Thread* self)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
ArtMethod* method = self->GetCurrentMethod(nullptr);
return method != nullptr
? method->GetDeclaringClass()->GetClassLoader()
: nullptr;
}
void Thread::ThrowNewWrappedException(const char* exception_class_descriptor,
const char* msg) {
DCHECK_EQ(this, Thread::Current());
ScopedObjectAccessUnchecked soa(this);
StackHandleScope<3> hs(soa.Self());
Handle<mirror::ClassLoader> class_loader(hs.NewHandle(GetCurrentClassLoader(soa.Self())));
ScopedLocalRef<jobject> cause(GetJniEnv(), soa.AddLocalReference<jobject>(GetException()));
ClearException();
Runtime* runtime = Runtime::Current();
auto* cl = runtime->GetClassLinker();
Handle<mirror::Class> exception_class(
hs.NewHandle(cl->FindClass(this, exception_class_descriptor, class_loader)));
if (UNLIKELY(exception_class.Get() == nullptr)) {
CHECK(IsExceptionPending());
LOG(ERROR) << "No exception class " << PrettyDescriptor(exception_class_descriptor);
return;
}
if (UNLIKELY(!runtime->GetClassLinker()->EnsureInitialized(soa.Self(), exception_class, true,
true))) {
DCHECK(IsExceptionPending());
return;
}
DCHECK(!runtime->IsStarted() || exception_class->IsThrowableClass());
Handle<mirror::Throwable> exception(
hs.NewHandle(down_cast<mirror::Throwable*>(exception_class->AllocObject(this))));
// If we couldn't allocate the exception, throw the pre-allocated out of memory exception.
if (exception.Get() == nullptr) {
SetException(Runtime::Current()->GetPreAllocatedOutOfMemoryError());
return;
}
// Choose an appropriate constructor and set up the arguments.
const char* signature;
ScopedLocalRef<jstring> msg_string(GetJniEnv(), nullptr);
if (msg != nullptr) {
// Ensure we remember this and the method over the String allocation.
msg_string.reset(
soa.AddLocalReference<jstring>(mirror::String::AllocFromModifiedUtf8(this, msg)));
if (UNLIKELY(msg_string.get() == nullptr)) {
CHECK(IsExceptionPending()); // OOME.
return;
}
if (cause.get() == nullptr) {
signature = "(Ljava/lang/String;)V";
} else {
signature = "(Ljava/lang/String;Ljava/lang/Throwable;)V";
}
} else {
if (cause.get() == nullptr) {
signature = "()V";
} else {
signature = "(Ljava/lang/Throwable;)V";
}
}
ArtMethod* exception_init_method =
exception_class->FindDeclaredDirectMethod("<init>", signature, cl->GetImagePointerSize());
CHECK(exception_init_method != nullptr) << "No <init>" << signature << " in "
<< PrettyDescriptor(exception_class_descriptor);
if (UNLIKELY(!runtime->IsStarted())) {
// Something is trying to throw an exception without a started runtime, which is the common
// case in the compiler. We won't be able to invoke the constructor of the exception, so set
// the exception fields directly.
if (msg != nullptr) {
exception->SetDetailMessage(down_cast<mirror::String*>(DecodeJObject(msg_string.get())));
}
if (cause.get() != nullptr) {
exception->SetCause(down_cast<mirror::Throwable*>(DecodeJObject(cause.get())));
}
ScopedLocalRef<jobject> trace(GetJniEnv(),
Runtime::Current()->IsActiveTransaction()
? CreateInternalStackTrace<true>(soa)
: CreateInternalStackTrace<false>(soa));
if (trace.get() != nullptr) {
exception->SetStackState(down_cast<mirror::Throwable*>(DecodeJObject(trace.get())));
}
SetException(exception.Get());
} else {
jvalue jv_args[2];
size_t i = 0;
if (msg != nullptr) {
jv_args[i].l = msg_string.get();
++i;
}
if (cause.get() != nullptr) {
jv_args[i].l = cause.get();
++i;
}
ScopedLocalRef<jobject> ref(soa.Env(), soa.AddLocalReference<jobject>(exception.Get()));
InvokeWithJValues(soa, ref.get(), soa.EncodeMethod(exception_init_method), jv_args);
if (LIKELY(!IsExceptionPending())) {
SetException(exception.Get());
}
}
}
void Thread::ThrowOutOfMemoryError(const char* msg) {
LOG(WARNING) << StringPrintf("Throwing OutOfMemoryError \"%s\"%s",
msg, (tls32_.throwing_OutOfMemoryError ? " (recursive case)" : ""));
if (!tls32_.throwing_OutOfMemoryError) {
tls32_.throwing_OutOfMemoryError = true;
ThrowNewException("Ljava/lang/OutOfMemoryError;", msg);
tls32_.throwing_OutOfMemoryError = false;
} else {
Dump(LOG(WARNING)); // The pre-allocated OOME has no stack, so help out and log one.
SetException(Runtime::Current()->GetPreAllocatedOutOfMemoryError());
}
}
Thread* Thread::CurrentFromGdb() {
return Thread::Current();
}
void Thread::DumpFromGdb() const {
std::ostringstream ss;
Dump(ss);
std::string str(ss.str());
// log to stderr for debugging command line processes
std::cerr << str;
#ifdef HAVE_ANDROID_OS
// log to logcat for debugging frameworks processes
LOG(INFO) << str;
#endif
}
// Explicitly instantiate 32 and 64bit thread offset dumping support.
template void Thread::DumpThreadOffset<4>(std::ostream& os, uint32_t offset);
template void Thread::DumpThreadOffset<8>(std::ostream& os, uint32_t offset);
template<size_t ptr_size>
void Thread::DumpThreadOffset(std::ostream& os, uint32_t offset) {
#define DO_THREAD_OFFSET(x, y) \
if (offset == x.Uint32Value()) { \
os << y; \
return; \
}
DO_THREAD_OFFSET(ThreadFlagsOffset<ptr_size>(), "state_and_flags")
DO_THREAD_OFFSET(CardTableOffset<ptr_size>(), "card_table")
DO_THREAD_OFFSET(ExceptionOffset<ptr_size>(), "exception")
DO_THREAD_OFFSET(PeerOffset<ptr_size>(), "peer");
DO_THREAD_OFFSET(JniEnvOffset<ptr_size>(), "jni_env")
DO_THREAD_OFFSET(SelfOffset<ptr_size>(), "self")
DO_THREAD_OFFSET(StackEndOffset<ptr_size>(), "stack_end")
DO_THREAD_OFFSET(ThinLockIdOffset<ptr_size>(), "thin_lock_thread_id")
DO_THREAD_OFFSET(TopOfManagedStackOffset<ptr_size>(), "top_quick_frame_method")
DO_THREAD_OFFSET(TopShadowFrameOffset<ptr_size>(), "top_shadow_frame")
DO_THREAD_OFFSET(TopHandleScopeOffset<ptr_size>(), "top_handle_scope")
DO_THREAD_OFFSET(ThreadSuspendTriggerOffset<ptr_size>(), "suspend_trigger")
#undef DO_THREAD_OFFSET
#define INTERPRETER_ENTRY_POINT_INFO(x) \
if (INTERPRETER_ENTRYPOINT_OFFSET(ptr_size, x).Uint32Value() == offset) { \
os << #x; \
return; \
}
INTERPRETER_ENTRY_POINT_INFO(pInterpreterToInterpreterBridge)
INTERPRETER_ENTRY_POINT_INFO(pInterpreterToCompiledCodeBridge)
#undef INTERPRETER_ENTRY_POINT_INFO
#define JNI_ENTRY_POINT_INFO(x) \
if (JNI_ENTRYPOINT_OFFSET(ptr_size, x).Uint32Value() == offset) { \
os << #x; \
return; \
}
JNI_ENTRY_POINT_INFO(pDlsymLookup)
#undef JNI_ENTRY_POINT_INFO
#define QUICK_ENTRY_POINT_INFO(x) \
if (QUICK_ENTRYPOINT_OFFSET(ptr_size, x).Uint32Value() == offset) { \
os << #x; \
return; \
}
QUICK_ENTRY_POINT_INFO(pAllocArray)
QUICK_ENTRY_POINT_INFO(pAllocArrayResolved)
QUICK_ENTRY_POINT_INFO(pAllocArrayWithAccessCheck)
QUICK_ENTRY_POINT_INFO(pAllocObject)
QUICK_ENTRY_POINT_INFO(pAllocObjectResolved)
QUICK_ENTRY_POINT_INFO(pAllocObjectInitialized)
QUICK_ENTRY_POINT_INFO(pAllocObjectWithAccessCheck)
QUICK_ENTRY_POINT_INFO(pCheckAndAllocArray)
QUICK_ENTRY_POINT_INFO(pCheckAndAllocArrayWithAccessCheck)
QUICK_ENTRY_POINT_INFO(pAllocStringFromBytes)
QUICK_ENTRY_POINT_INFO(pAllocStringFromChars)
QUICK_ENTRY_POINT_INFO(pAllocStringFromString)
QUICK_ENTRY_POINT_INFO(pInstanceofNonTrivial)
QUICK_ENTRY_POINT_INFO(pCheckCast)
QUICK_ENTRY_POINT_INFO(pInitializeStaticStorage)
QUICK_ENTRY_POINT_INFO(pInitializeTypeAndVerifyAccess)
QUICK_ENTRY_POINT_INFO(pInitializeType)
QUICK_ENTRY_POINT_INFO(pResolveString)
QUICK_ENTRY_POINT_INFO(pSet8Instance)
QUICK_ENTRY_POINT_INFO(pSet8Static)
QUICK_ENTRY_POINT_INFO(pSet16Instance)
QUICK_ENTRY_POINT_INFO(pSet16Static)
QUICK_ENTRY_POINT_INFO(pSet32Instance)
QUICK_ENTRY_POINT_INFO(pSet32Static)
QUICK_ENTRY_POINT_INFO(pSet64Instance)
QUICK_ENTRY_POINT_INFO(pSet64Static)
QUICK_ENTRY_POINT_INFO(pSetObjInstance)
QUICK_ENTRY_POINT_INFO(pSetObjStatic)
QUICK_ENTRY_POINT_INFO(pGetByteInstance)
QUICK_ENTRY_POINT_INFO(pGetBooleanInstance)
QUICK_ENTRY_POINT_INFO(pGetByteStatic)
QUICK_ENTRY_POINT_INFO(pGetBooleanStatic)
QUICK_ENTRY_POINT_INFO(pGetShortInstance)
QUICK_ENTRY_POINT_INFO(pGetCharInstance)
QUICK_ENTRY_POINT_INFO(pGetShortStatic)
QUICK_ENTRY_POINT_INFO(pGetCharStatic)
QUICK_ENTRY_POINT_INFO(pGet32Instance)
QUICK_ENTRY_POINT_INFO(pGet32Static)
QUICK_ENTRY_POINT_INFO(pGet64Instance)
QUICK_ENTRY_POINT_INFO(pGet64Static)
QUICK_ENTRY_POINT_INFO(pGetObjInstance)
QUICK_ENTRY_POINT_INFO(pGetObjStatic)
QUICK_ENTRY_POINT_INFO(pAputObjectWithNullAndBoundCheck)
QUICK_ENTRY_POINT_INFO(pAputObjectWithBoundCheck)
QUICK_ENTRY_POINT_INFO(pAputObject)
QUICK_ENTRY_POINT_INFO(pHandleFillArrayData)
QUICK_ENTRY_POINT_INFO(pJniMethodStart)
QUICK_ENTRY_POINT_INFO(pJniMethodStartSynchronized)
QUICK_ENTRY_POINT_INFO(pJniMethodEnd)
QUICK_ENTRY_POINT_INFO(pJniMethodEndSynchronized)
QUICK_ENTRY_POINT_INFO(pJniMethodEndWithReference)
QUICK_ENTRY_POINT_INFO(pJniMethodEndWithReferenceSynchronized)
QUICK_ENTRY_POINT_INFO(pQuickGenericJniTrampoline)
QUICK_ENTRY_POINT_INFO(pLockObject)
QUICK_ENTRY_POINT_INFO(pUnlockObject)
QUICK_ENTRY_POINT_INFO(pCmpgDouble)
QUICK_ENTRY_POINT_INFO(pCmpgFloat)
QUICK_ENTRY_POINT_INFO(pCmplDouble)
QUICK_ENTRY_POINT_INFO(pCmplFloat)
QUICK_ENTRY_POINT_INFO(pFmod)
QUICK_ENTRY_POINT_INFO(pL2d)
QUICK_ENTRY_POINT_INFO(pFmodf)
QUICK_ENTRY_POINT_INFO(pL2f)
QUICK_ENTRY_POINT_INFO(pD2iz)
QUICK_ENTRY_POINT_INFO(pF2iz)
QUICK_ENTRY_POINT_INFO(pIdivmod)
QUICK_ENTRY_POINT_INFO(pD2l)
QUICK_ENTRY_POINT_INFO(pF2l)
QUICK_ENTRY_POINT_INFO(pLdiv)
QUICK_ENTRY_POINT_INFO(pLmod)
QUICK_ENTRY_POINT_INFO(pLmul)
QUICK_ENTRY_POINT_INFO(pShlLong)
QUICK_ENTRY_POINT_INFO(pShrLong)
QUICK_ENTRY_POINT_INFO(pUshrLong)
QUICK_ENTRY_POINT_INFO(pIndexOf)
QUICK_ENTRY_POINT_INFO(pStringCompareTo)
QUICK_ENTRY_POINT_INFO(pMemcpy)
QUICK_ENTRY_POINT_INFO(pQuickImtConflictTrampoline)
QUICK_ENTRY_POINT_INFO(pQuickResolutionTrampoline)
QUICK_ENTRY_POINT_INFO(pQuickToInterpreterBridge)
QUICK_ENTRY_POINT_INFO(pInvokeDirectTrampolineWithAccessCheck)
QUICK_ENTRY_POINT_INFO(pInvokeInterfaceTrampolineWithAccessCheck)
QUICK_ENTRY_POINT_INFO(pInvokeStaticTrampolineWithAccessCheck)
QUICK_ENTRY_POINT_INFO(pInvokeSuperTrampolineWithAccessCheck)
QUICK_ENTRY_POINT_INFO(pInvokeVirtualTrampolineWithAccessCheck)
QUICK_ENTRY_POINT_INFO(pTestSuspend)
QUICK_ENTRY_POINT_INFO(pDeliverException)
QUICK_ENTRY_POINT_INFO(pThrowArrayBounds)
QUICK_ENTRY_POINT_INFO(pThrowDivZero)
QUICK_ENTRY_POINT_INFO(pThrowNoSuchMethod)
QUICK_ENTRY_POINT_INFO(pThrowNullPointer)
QUICK_ENTRY_POINT_INFO(pThrowStackOverflow)
QUICK_ENTRY_POINT_INFO(pDeoptimize)
QUICK_ENTRY_POINT_INFO(pA64Load)
QUICK_ENTRY_POINT_INFO(pA64Store)
QUICK_ENTRY_POINT_INFO(pNewEmptyString)
QUICK_ENTRY_POINT_INFO(pNewStringFromBytes_B)
QUICK_ENTRY_POINT_INFO(pNewStringFromBytes_BI)
QUICK_ENTRY_POINT_INFO(pNewStringFromBytes_BII)
QUICK_ENTRY_POINT_INFO(pNewStringFromBytes_BIII)
QUICK_ENTRY_POINT_INFO(pNewStringFromBytes_BIIString)
QUICK_ENTRY_POINT_INFO(pNewStringFromBytes_BString)
QUICK_ENTRY_POINT_INFO(pNewStringFromBytes_BIICharset)
QUICK_ENTRY_POINT_INFO(pNewStringFromBytes_BCharset)
QUICK_ENTRY_POINT_INFO(pNewStringFromChars_C)
QUICK_ENTRY_POINT_INFO(pNewStringFromChars_CII)
QUICK_ENTRY_POINT_INFO(pNewStringFromChars_IIC)
QUICK_ENTRY_POINT_INFO(pNewStringFromCodePoints)
QUICK_ENTRY_POINT_INFO(pNewStringFromString)
QUICK_ENTRY_POINT_INFO(pNewStringFromStringBuffer)
QUICK_ENTRY_POINT_INFO(pNewStringFromStringBuilder)
QUICK_ENTRY_POINT_INFO(pReadBarrierJni)
#undef QUICK_ENTRY_POINT_INFO
os << offset;
}
void Thread::QuickDeliverException() {
// Get exception from thread.
mirror::Throwable* exception = GetException();
CHECK(exception != nullptr);
// Don't leave exception visible while we try to find the handler, which may cause class
// resolution.
ClearException();
bool is_deoptimization = (exception == GetDeoptimizationException());
QuickExceptionHandler exception_handler(this, is_deoptimization);
if (is_deoptimization) {
exception_handler.DeoptimizeStack();
} else {
exception_handler.FindCatch(exception);
}
exception_handler.UpdateInstrumentationStack();
exception_handler.DoLongJump();
}
Context* Thread::GetLongJumpContext() {
Context* result = tlsPtr_.long_jump_context;
if (result == nullptr) {
result = Context::Create();
} else {
tlsPtr_.long_jump_context = nullptr; // Avoid context being shared.
result->Reset();
}
return result;
}
// Note: this visitor may return with a method set, but dex_pc_ being DexFile:kDexNoIndex. This is
// so we don't abort in a special situation (thinlocked monitor) when dumping the Java stack.
struct CurrentMethodVisitor FINAL : public StackVisitor {
CurrentMethodVisitor(Thread* thread, Context* context, bool abort_on_error)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
: StackVisitor(thread, context, StackVisitor::StackWalkKind::kIncludeInlinedFrames),
this_object_(nullptr),
method_(nullptr),
dex_pc_(0),
abort_on_error_(abort_on_error) {}
bool VisitFrame() OVERRIDE SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
ArtMethod* m = GetMethod();
if (m->IsRuntimeMethod()) {
// Continue if this is a runtime method.
return true;
}
if (context_ != nullptr) {
this_object_ = GetThisObject();
}
method_ = m;
dex_pc_ = GetDexPc(abort_on_error_);
return false;
}
mirror::Object* this_object_;
ArtMethod* method_;
uint32_t dex_pc_;
const bool abort_on_error_;
};
ArtMethod* Thread::GetCurrentMethod(uint32_t* dex_pc, bool abort_on_error) const {
CurrentMethodVisitor visitor(const_cast<Thread*>(this), nullptr, abort_on_error);
visitor.WalkStack(false);
if (dex_pc != nullptr) {
*dex_pc = visitor.dex_pc_;
}
return visitor.method_;
}
bool Thread::HoldsLock(mirror::Object* object) const {
if (object == nullptr) {
return false;
}
return object->GetLockOwnerThreadId() == GetThreadId();
}
// RootVisitor parameters are: (const Object* obj, size_t vreg, const StackVisitor* visitor).
template <typename RootVisitor>
class ReferenceMapVisitor : public StackVisitor {
public:
ReferenceMapVisitor(Thread* thread, Context* context, RootVisitor& visitor)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
// We are visiting the references in compiled frames, so we do not need
// to know the inlined frames.
: StackVisitor(thread, context, StackVisitor::StackWalkKind::kSkipInlinedFrames),
visitor_(visitor) {}
bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
if (false) {
LOG(INFO) << "Visiting stack roots in " << PrettyMethod(GetMethod())
<< StringPrintf("@ PC:%04x", GetDexPc());
}
ShadowFrame* shadow_frame = GetCurrentShadowFrame();
if (shadow_frame != nullptr) {
VisitShadowFrame(shadow_frame);
} else {
VisitQuickFrame();
}
return true;
}
void VisitShadowFrame(ShadowFrame* shadow_frame) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
ArtMethod* m = shadow_frame->GetMethod();
DCHECK(m != nullptr);
size_t num_regs = shadow_frame->NumberOfVRegs();
if (m->IsNative() || shadow_frame->HasReferenceArray()) {
// handle scope for JNI or References for interpreter.
for (size_t reg = 0; reg < num_regs; ++reg) {
mirror::Object* ref = shadow_frame->GetVRegReference(reg);
if (ref != nullptr) {
mirror::Object* new_ref = ref;
visitor_(&new_ref, reg, this);
if (new_ref != ref) {
shadow_frame->SetVRegReference(reg, new_ref);
}
}
}
} else {
// Java method.
// Portable path use DexGcMap and store in Method.native_gc_map_.
const uint8_t* gc_map = m->GetNativeGcMap(sizeof(void*));
CHECK(gc_map != nullptr) << PrettyMethod(m);
verifier::DexPcToReferenceMap dex_gc_map(gc_map);
uint32_t dex_pc = shadow_frame->GetDexPC();
const uint8_t* reg_bitmap = dex_gc_map.FindBitMap(dex_pc);
DCHECK(reg_bitmap != nullptr);
num_regs = std::min(dex_gc_map.RegWidth() * 8, num_regs);
for (size_t reg = 0; reg < num_regs; ++reg) {
if (TestBitmap(reg, reg_bitmap)) {
mirror::Object* ref = shadow_frame->GetVRegReference(reg);
if (ref != nullptr) {
mirror::Object* new_ref = ref;
visitor_(&new_ref, reg, this);
if (new_ref != ref) {
shadow_frame->SetVRegReference(reg, new_ref);
}
}
}
}
}
}
private:
void VisitQuickFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
auto* cur_quick_frame = GetCurrentQuickFrame();
DCHECK(cur_quick_frame != nullptr);
auto* m = *cur_quick_frame;
// Process register map (which native and runtime methods don't have)
if (!m->IsNative() && !m->IsRuntimeMethod() && !m->IsProxyMethod()) {
if (m->IsOptimized(sizeof(void*))) {
auto* vreg_base = reinterpret_cast<StackReference<mirror::Object>*>(
reinterpret_cast<uintptr_t>(cur_quick_frame));
Runtime* runtime = Runtime::Current();
const void* entry_point = runtime->GetInstrumentation()->GetQuickCodeFor(m, sizeof(void*));
uintptr_t native_pc_offset = m->NativeQuickPcOffset(GetCurrentQuickFramePc(), entry_point);
CodeInfo code_info = m->GetOptimizedCodeInfo();
StackMap map = code_info.GetStackMapForNativePcOffset(native_pc_offset);
MemoryRegion mask = map.GetStackMask(code_info);
// Visit stack entries that hold pointers.
for (size_t i = 0; i < mask.size_in_bits(); ++i) {
if (mask.LoadBit(i)) {
auto* ref_addr = vreg_base + i;
mirror::Object* ref = ref_addr->AsMirrorPtr();
if (ref != nullptr) {
mirror::Object* new_ref = ref;
visitor_(&new_ref, -1, this);
if (ref != new_ref) {
ref_addr->Assign(new_ref);
}
}
}
}
// Visit callee-save registers that hold pointers.
uint32_t register_mask = map.GetRegisterMask(code_info);
for (size_t i = 0; i < BitSizeOf<uint32_t>(); ++i) {
if (register_mask & (1 << i)) {
mirror::Object** ref_addr = reinterpret_cast<mirror::Object**>(GetGPRAddress(i));
if (*ref_addr != nullptr) {
visitor_(ref_addr, -1, this);
}
}
}
} else {
const uint8_t* native_gc_map = m->GetNativeGcMap(sizeof(void*));
CHECK(native_gc_map != nullptr) << PrettyMethod(m);
const DexFile::CodeItem* code_item = m->GetCodeItem();
// Can't be null or how would we compile its instructions?
DCHECK(code_item != nullptr) << PrettyMethod(m);
NativePcOffsetToReferenceMap map(native_gc_map);
size_t num_regs = std::min(map.RegWidth() * 8,
static_cast<size_t>(code_item->registers_size_));
if (num_regs > 0) {
Runtime* runtime = Runtime::Current();
const void* entry_point = runtime->GetInstrumentation()->GetQuickCodeFor(m, sizeof(void*));
uintptr_t native_pc_offset = m->NativeQuickPcOffset(GetCurrentQuickFramePc(), entry_point);
const uint8_t* reg_bitmap = map.FindBitMap(native_pc_offset);
DCHECK(reg_bitmap != nullptr);
const void* code_pointer = ArtMethod::EntryPointToCodePointer(entry_point);
const VmapTable vmap_table(m->GetVmapTable(code_pointer, sizeof(void*)));
QuickMethodFrameInfo frame_info = m->GetQuickFrameInfo(code_pointer);
// For all dex registers in the bitmap
DCHECK(cur_quick_frame != nullptr);
for (size_t reg = 0; reg < num_regs; ++reg) {
// Does this register hold a reference?
if (TestBitmap(reg, reg_bitmap)) {
uint32_t vmap_offset;
if (vmap_table.IsInContext(reg, kReferenceVReg, &vmap_offset)) {
int vmap_reg = vmap_table.ComputeRegister(frame_info.CoreSpillMask(), vmap_offset,
kReferenceVReg);
// This is sound as spilled GPRs will be word sized (ie 32 or 64bit).
mirror::Object** ref_addr =
reinterpret_cast<mirror::Object**>(GetGPRAddress(vmap_reg));
if (*ref_addr != nullptr) {
visitor_(ref_addr, reg, this);
}
} else {
StackReference<mirror::Object>* ref_addr =
reinterpret_cast<StackReference<mirror::Object>*>(GetVRegAddrFromQuickCode(
cur_quick_frame, code_item, frame_info.CoreSpillMask(),
frame_info.FpSpillMask(), frame_info.FrameSizeInBytes(), reg));
mirror::Object* ref = ref_addr->AsMirrorPtr();
if (ref != nullptr) {
mirror::Object* new_ref = ref;
visitor_(&new_ref, reg, this);
if (ref != new_ref) {
ref_addr->Assign(new_ref);
}
}
}
}
}
}
}
}
}
// Visitor for when we visit a root.
RootVisitor& visitor_;
};
class RootCallbackVisitor {
public:
RootCallbackVisitor(RootVisitor* visitor, uint32_t tid) : visitor_(visitor), tid_(tid) {}
void operator()(mirror::Object** obj, size_t vreg, const StackVisitor* stack_visitor) const
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
visitor_->VisitRoot(obj, JavaFrameRootInfo(tid_, stack_visitor, vreg));
}
private:
RootVisitor* const visitor_;
const uint32_t tid_;
};
void Thread::VisitRoots(RootVisitor* visitor) {
const uint32_t thread_id = GetThreadId();
visitor->VisitRootIfNonNull(&tlsPtr_.opeer, RootInfo(kRootThreadObject, thread_id));
if (tlsPtr_.exception != nullptr && tlsPtr_.exception != GetDeoptimizationException()) {
visitor->VisitRoot(reinterpret_cast<mirror::Object**>(&tlsPtr_.exception),
RootInfo(kRootNativeStack, thread_id));
}
visitor->VisitRootIfNonNull(&tlsPtr_.monitor_enter_object, RootInfo(kRootNativeStack, thread_id));
tlsPtr_.jni_env->locals.VisitRoots(visitor, RootInfo(kRootJNILocal, thread_id));
tlsPtr_.jni_env->monitors.VisitRoots(visitor, RootInfo(kRootJNIMonitor, thread_id));
HandleScopeVisitRoots(visitor, thread_id);
if (tlsPtr_.debug_invoke_req != nullptr) {
tlsPtr_.debug_invoke_req->VisitRoots(visitor, RootInfo(kRootDebugger, thread_id));
}
if (tlsPtr_.stacked_shadow_frame_record != nullptr) {
RootCallbackVisitor visitor_to_callback(visitor, thread_id);
ReferenceMapVisitor<RootCallbackVisitor> mapper(this, nullptr, visitor_to_callback);
for (StackedShadowFrameRecord* record = tlsPtr_.stacked_shadow_frame_record;
record != nullptr;
record = record->GetLink()) {
for (ShadowFrame* shadow_frame = record->GetShadowFrame();
shadow_frame != nullptr;
shadow_frame = shadow_frame->GetLink()) {
mapper.VisitShadowFrame(shadow_frame);
}
}
}
if (tlsPtr_.deoptimization_return_value_stack != nullptr) {
for (DeoptimizationReturnValueRecord* record = tlsPtr_.deoptimization_return_value_stack;
record != nullptr;
record = record->GetLink()) {
if (record->IsReference()) {
visitor->VisitRootIfNonNull(record->GetGCRoot(),
RootInfo(kRootThreadObject, thread_id));
}
}
}
for (auto* verifier = tlsPtr_.method_verifier; verifier != nullptr; verifier = verifier->link_) {
verifier->VisitRoots(visitor, RootInfo(kRootNativeStack, thread_id));
}
// Visit roots on this thread's stack
Context* context = GetLongJumpContext();
RootCallbackVisitor visitor_to_callback(visitor, thread_id);
ReferenceMapVisitor<RootCallbackVisitor> mapper(this, context, visitor_to_callback);
mapper.WalkStack();
ReleaseLongJumpContext(context);
for (instrumentation::InstrumentationStackFrame& frame : *GetInstrumentationStack()) {
visitor->VisitRootIfNonNull(&frame.this_object_, RootInfo(kRootVMInternal, thread_id));
}
}
class VerifyRootVisitor : public SingleRootVisitor {
public:
void VisitRoot(mirror::Object* root, const RootInfo& info ATTRIBUTE_UNUSED)
OVERRIDE SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
VerifyObject(root);
}
};
void Thread::VerifyStackImpl() {
VerifyRootVisitor visitor;
std::unique_ptr<Context> context(Context::Create());
RootCallbackVisitor visitor_to_callback(&visitor, GetThreadId());
ReferenceMapVisitor<RootCallbackVisitor> mapper(this, context.get(), visitor_to_callback);
mapper.WalkStack();
}
// Set the stack end to that to be used during a stack overflow
void Thread::SetStackEndForStackOverflow() {
// During stack overflow we allow use of the full stack.
if (tlsPtr_.stack_end == tlsPtr_.stack_begin) {
// However, we seem to have already extended to use the full stack.
LOG(ERROR) << "Need to increase kStackOverflowReservedBytes (currently "
<< GetStackOverflowReservedBytes(kRuntimeISA) << ")?";
DumpStack(LOG(ERROR));
LOG(FATAL) << "Recursive stack overflow.";
}
tlsPtr_.stack_end = tlsPtr_.stack_begin;
// Remove the stack overflow protection if is it set up.
bool implicit_stack_check = !Runtime::Current()->ExplicitStackOverflowChecks();
if (implicit_stack_check) {
if (!UnprotectStack()) {
LOG(ERROR) << "Unable to remove stack protection for stack overflow";
}
}
}
void Thread::SetTlab(uint8_t* start, uint8_t* end) {
DCHECK_LE(start, end);
tlsPtr_.thread_local_start = start;
tlsPtr_.thread_local_pos = tlsPtr_.thread_local_start;
tlsPtr_.thread_local_end = end;
tlsPtr_.thread_local_objects = 0;
}
bool Thread::HasTlab() const {
bool has_tlab = tlsPtr_.thread_local_pos != nullptr;
if (has_tlab) {
DCHECK(tlsPtr_.thread_local_start != nullptr && tlsPtr_.thread_local_end != nullptr);
} else {
DCHECK(tlsPtr_.thread_local_start == nullptr && tlsPtr_.thread_local_end == nullptr);
}
return has_tlab;
}
std::ostream& operator<<(std::ostream& os, const Thread& thread) {
thread.ShortDump(os);
return os;
}
void Thread::ProtectStack() {
void* pregion = tlsPtr_.stack_begin - kStackOverflowProtectedSize;
VLOG(threads) << "Protecting stack at " << pregion;
if (mprotect(pregion, kStackOverflowProtectedSize, PROT_NONE) == -1) {
LOG(FATAL) << "Unable to create protected region in stack for implicit overflow check. "
"Reason: "
<< strerror(errno) << " size: " << kStackOverflowProtectedSize;
}
}
bool Thread::UnprotectStack() {
void* pregion = tlsPtr_.stack_begin - kStackOverflowProtectedSize;
VLOG(threads) << "Unprotecting stack at " << pregion;
return mprotect(pregion, kStackOverflowProtectedSize, PROT_READ|PROT_WRITE) == 0;
}
void Thread::ActivateSingleStepControl(SingleStepControl* ssc) {
CHECK(Dbg::IsDebuggerActive());
CHECK(GetSingleStepControl() == nullptr) << "Single step already active in thread " << *this;
CHECK(ssc != nullptr);
tlsPtr_.single_step_control = ssc;
}
void Thread::DeactivateSingleStepControl() {
CHECK(Dbg::IsDebuggerActive());
CHECK(GetSingleStepControl() != nullptr) << "Single step not active in thread " << *this;
SingleStepControl* ssc = GetSingleStepControl();
tlsPtr_.single_step_control = nullptr;
delete ssc;
}
void Thread::SetDebugInvokeReq(DebugInvokeReq* req) {
CHECK(Dbg::IsDebuggerActive());
CHECK(GetInvokeReq() == nullptr) << "Debug invoke req already active in thread " << *this;
CHECK(Thread::Current() != this) << "Debug invoke can't be dispatched by the thread itself";
CHECK(req != nullptr);
tlsPtr_.debug_invoke_req = req;
}
void Thread::ClearDebugInvokeReq() {
CHECK(GetInvokeReq() != nullptr) << "Debug invoke req not active in thread " << *this;
CHECK(Thread::Current() == this) << "Debug invoke must be finished by the thread itself";
DebugInvokeReq* req = tlsPtr_.debug_invoke_req;
tlsPtr_.debug_invoke_req = nullptr;
delete req;
}
void Thread::PushVerifier(verifier::MethodVerifier* verifier) {
verifier->link_ = tlsPtr_.method_verifier;
tlsPtr_.method_verifier = verifier;
}
void Thread::PopVerifier(verifier::MethodVerifier* verifier) {
CHECK_EQ(tlsPtr_.method_verifier, verifier);
tlsPtr_.method_verifier = verifier->link_;
}
} // namespace art