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LeafOS / LeafOS-Project / android_art / 306057fd278d75bf3794bd5243a3b6652c487d18 / . / src / thread.cc
blob: 484806e3f9e41f5be8ae83ca4eb31bd2850be175 [file] [log] [blame]
/*
* 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 "thread.h"
#include <dynamic_annotations.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 "base/mutex.h"
#include "class_linker.h"
#include "class_loader.h"
#include "cutils/atomic.h"
#include "cutils/atomic-inline.h"
#include "debugger.h"
#include "gc_map.h"
#include "heap.h"
#include "jni_internal.h"
#include "monitor.h"
#include "oat/runtime/context.h"
#include "object.h"
#include "object_utils.h"
#include "reflection.h"
#include "runtime.h"
#include "runtime_support.h"
#include "scoped_thread_state_change.h"
#include "ScopedLocalRef.h"
#include "sirt_ref.h"
#include "gc/space.h"
#include "stack.h"
#include "stack_indirect_reference_table.h"
#include "thread_list.h"
#include "utils.h"
#include "verifier/dex_gc_map.h"
#include "well_known_classes.h"
namespace art {
pthread_key_t Thread::pthread_key_self_;
ConditionVariable* Thread::resume_cond_;
static const char* kThreadNameDuringStartup = "<native thread without managed peer>";
void Thread::InitCardTable() {
card_table_ = Runtime::Current()->GetHeap()->GetCardTable()->GetBiasedBegin();
}
#if !defined(__APPLE__)
static void UnimplementedEntryPoint() {
UNIMPLEMENTED(FATAL);
}
#endif
void Thread::InitFunctionPointers() {
#if !defined(__APPLE__) // The Mac GCC is too old to accept this code.
// Insert a placeholder so we can easily tell if we call an unimplemented entry point.
uintptr_t* begin = reinterpret_cast<uintptr_t*>(&entrypoints_);
uintptr_t* end = reinterpret_cast<uintptr_t*>(reinterpret_cast<uint8_t*>(begin) + sizeof(entrypoints_));
for (uintptr_t* it = begin; it != end; ++it) {
*it = reinterpret_cast<uintptr_t>(UnimplementedEntryPoint);
}
#endif
InitEntryPoints(&entrypoints_);
}
void Thread::SetDebuggerUpdatesEnabled(bool enabled) {
LOG(INFO) << "Turning debugger updates " << (enabled ? "on" : "off") << " for " << *this;
#if !defined(ART_USE_LLVM_COMPILER)
ChangeDebuggerEntryPoint(&entrypoints_, enabled);
#else
UNIMPLEMENTED(FATAL);
#endif
}
void Thread::SetDeoptimizationShadowFrame(ShadowFrame* sf, const JValue& ret_val) {
CHECK(sf != NULL);
deoptimization_shadow_frame_ = sf;
deoptimization_return_value_.SetJ(ret_val.GetJ());
}
ShadowFrame* Thread::GetAndClearDeoptimizationShadowFrame(JValue* ret_val) {
ShadowFrame* sf = deoptimization_shadow_frame_;
DCHECK(sf != NULL);
deoptimization_shadow_frame_ = NULL;
ret_val->SetJ(deoptimization_return_value_.GetJ());
return sf;
}
void Thread::InitTid() {
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 == NULL) {
LOG(ERROR) << "Thread attaching to non-existent runtime: " << *self;
return NULL;
}
{
// TODO: pass self to MutexLock - requires self to equal Thread::Current(), which is only true
// after self->Init().
MutexLock mu(NULL, *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->IsShuttingDown());
self->Init(runtime->GetThreadList(), runtime->GetJavaVM());
Runtime::Current()->EndThreadBirth();
}
{
ScopedObjectAccess soa(self);
// Copy peer into self, deleting global reference when done.
CHECK(self->jpeer_ != NULL);
self->opeer_ = soa.Decode<Object*>(self->jpeer_);
self->GetJniEnv()->DeleteGlobalRef(self->jpeer_);
self->jpeer_ = NULL;
{
SirtRef<String> thread_name(self, self->GetThreadName(soa));
self->SetThreadName(thread_name->ToModifiedUtf8().c_str());
}
Dbg::PostThreadStart(self);
// Invoke the 'run' method of our java.lang.Thread.
Object* receiver = self->opeer_;
jmethodID mid = WellKnownClasses::java_lang_Thread_run;
AbstractMethod* m =
receiver->GetClass()->FindVirtualMethodForVirtualOrInterface(soa.DecodeMethod(mid));
m->Invoke(self, receiver, NULL, NULL);
}
// Detach and delete self.
Runtime::Current()->GetThreadList()->Unregister(self);
return NULL;
}
Thread* Thread::FromManagedThread(const ScopedObjectAccessUnchecked& soa, Object* thread_peer) {
Field* f = soa.DecodeField(WellKnownClasses::java_lang_Thread_vmData);
Thread* result = reinterpret_cast<Thread*>(static_cast<uintptr_t>(f->GetInt(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 != NULL && !result->IsSuspended()) {
Locks::thread_list_lock_->AssertHeld(soa.Self());
}
}
return result;
}
Thread* Thread::FromManagedThread(const ScopedObjectAccessUnchecked& soa, jobject java_thread) {
return FromManagedThread(soa, soa.Decode<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;
}
// 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 += Thread::kStackOverflowReservedBytes;
// 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;
}
static void SigAltStack(stack_t* new_stack, stack_t* old_stack) {
if (sigaltstack(new_stack, old_stack) == -1) {
PLOG(FATAL) << "sigaltstack failed";
}
}
static void SetUpAlternateSignalStack() {
// Create and set an alternate signal stack.
stack_t ss;
ss.ss_sp = new uint8_t[SIGSTKSZ];
ss.ss_size = SIGSTKSZ;
ss.ss_flags = 0;
CHECK(ss.ss_sp != NULL);
SigAltStack(&ss, NULL);
// Double-check that it worked.
ss.ss_sp = NULL;
SigAltStack(NULL, &ss);
VLOG(threads) << "Alternate signal stack is " << PrettySize(ss.ss_size) << " at " << ss.ss_sp;
}
static void TearDownAlternateSignalStack() {
// Get the pointer so we can free the memory.
stack_t ss;
SigAltStack(NULL, &ss);
uint8_t* allocated_signal_stack = reinterpret_cast<uint8_t*>(ss.ss_sp);
// Tell the kernel to stop using it.
ss.ss_sp = NULL;
ss.ss_flags = SS_DISABLE;
ss.ss_size = SIGSTKSZ; // Avoid ENOMEM failure with Mac OS' buggy libc.
SigAltStack(&ss, NULL);
// Free it.
delete[] allocated_signal_stack;
}
void Thread::CreateNativeThread(JNIEnv* env, jobject java_peer, size_t stack_size, bool is_daemon) {
CHECK(java_peer != NULL);
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->IsShuttingDown()) {
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->jpeer_ = env->NewGlobalRef(java_peer);
stack_size = FixStackSize(stack_size);
// Thread.start is synchronized, so we know that vmData is 0, and know that we're not racing to
// assign it.
env->SetIntField(java_peer, WellKnownClasses::java_lang_Thread_vmData,
reinterpret_cast<jint>(child_thread));
pthread_t new_pthread;
pthread_attr_t attr;
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);
int 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(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->jpeer_);
child_thread->jpeer_ = NULL;
delete child_thread;
child_thread = NULL;
// TODO: remove from thread group?
env->SetIntField(java_peer, WellKnownClasses::java_lang_Thread_vmData, 0);
{
std::string msg(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());
}
}
}
void Thread::Init(ThreadList* thread_list, JavaVMExt* java_vm) {
// 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() == NULL);
SetUpAlternateSignalStack();
InitCpu();
InitFunctionPointers();
InitCardTable();
InitTid();
if (Runtime::Current()->InterpreterOnly()) {
AtomicSetFlag(kEnterInterpreter);
}
// Set pthread_self_ ahead of pthread_setspecific, that makes Thread::Current function, this
// avoids pthread_self_ ever being invalid when discovered from Thread::Current().
pthread_self_ = pthread_self();
CHECK_PTHREAD_CALL(pthread_setspecific, (Thread::pthread_key_self_, this), "attach self");
DCHECK_EQ(Thread::Current(), this);
thin_lock_id_ = thread_list->AllocThreadId(this);
InitStackHwm();
jni_env_ = new JNIEnvExt(this, java_vm);
thread_list->Register(this);
}
Thread* Thread::Attach(const char* thread_name, bool as_daemon, jobject thread_group,
bool create_peer) {
Thread* self;
Runtime* runtime = Runtime::Current();
if (runtime == NULL) {
LOG(ERROR) << "Thread attaching to non-existent runtime: " << thread_name;
return NULL;
}
{
MutexLock mu(NULL, *Locks::runtime_shutdown_lock_);
if (runtime->IsShuttingDown()) {
LOG(ERROR) << "Thread attaching while runtime is shutting down: " << thread_name;
return NULL;
} else {
Runtime::Current()->StartThreadBirth();
self = new Thread(as_daemon);
self->Init(runtime->GetThreadList(), runtime->GetJavaVM());
Runtime::Current()->EndThreadBirth();
}
}
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);
} else {
// These aren't necessary, but they improve diagnostics for unit tests & command-line tools.
if (thread_name != NULL) {
self->name_->assign(thread_name);
::art::SetThreadName(thread_name);
}
}
return self;
}
void Thread::CreatePeer(const char* name, bool as_daemon, jobject thread_group) {
Runtime* runtime = Runtime::Current();
CHECK(runtime->IsStarted());
JNIEnv* env = jni_env_;
if (thread_group == NULL) {
thread_group = runtime->GetMainThreadGroup();
}
ScopedLocalRef<jobject> thread_name(env, env->NewStringUTF(name));
jint thread_priority = GetNativePriority();
jboolean thread_is_daemon = as_daemon;
ScopedLocalRef<jobject> peer(env, env->AllocObject(WellKnownClasses::java_lang_Thread));
if (peer.get() == NULL) {
CHECK(IsExceptionPending());
return;
}
{
ScopedObjectAccess soa(this);
opeer_ = soa.Decode<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);
AssertNoPendingException();
Thread* self = this;
DCHECK_EQ(self, Thread::Current());
jni_env_->SetIntField(peer.get(), WellKnownClasses::java_lang_Thread_vmData,
reinterpret_cast<jint>(self));
ScopedObjectAccess soa(self);
SirtRef<String> peer_thread_name(soa.Self(), GetThreadName(soa));
if (peer_thread_name.get() == NULL) {
// 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.
soa.DecodeField(WellKnownClasses::java_lang_Thread_daemon)->
SetBoolean(opeer_, thread_is_daemon);
soa.DecodeField(WellKnownClasses::java_lang_Thread_group)->
SetObject(opeer_, soa.Decode<Object*>(thread_group));
soa.DecodeField(WellKnownClasses::java_lang_Thread_name)->
SetObject(opeer_, soa.Decode<Object*>(thread_name.get()));
soa.DecodeField(WellKnownClasses::java_lang_Thread_priority)->
SetInt(opeer_, thread_priority);
peer_thread_name.reset(GetThreadName(soa));
}
// 'thread_name' may have been null, so don't trust 'peer_thread_name' to be non-null.
if (peer_thread_name.get() != NULL) {
SetThreadName(peer_thread_name->ToModifiedUtf8().c_str());
}
}
void Thread::SetThreadName(const char* name) {
name_->assign(name);
::art::SetThreadName(name);
Dbg::DdmSendThreadNotification(this, CHUNK_TYPE("THNM"));
}
void Thread::InitStackHwm() {
void* stack_base;
size_t stack_size;
GetThreadStack(pthread_self_, stack_base, stack_size);
// TODO: include this in the thread dumps; potentially useful in SIGQUIT output?
VLOG(threads) << StringPrintf("Native stack is at %p (%s)", stack_base, PrettySize(stack_size).c_str());
stack_begin_ = reinterpret_cast<byte*>(stack_base);
stack_size_ = stack_size;
if (stack_size_ <= kStackOverflowReservedBytes) {
LOG(FATAL) << "Attempt to attach a thread with a too-small stack (" << stack_size_ << " bytes)";
}
// TODO: move this into the Linux GetThreadStack implementation.
#if !defined(__APPLE__)
// If we're the main thread, check whether we were run with an unlimited stack. In that case,
// glibc will have reported a 2GB stack for our 32-bit process, and our stack overflow detection
// will be broken because we'll die long before we get close to 2GB.
bool is_main_thread = (::art::GetTid() == getpid());
if (is_main_thread) {
rlimit stack_limit;
if (getrlimit(RLIMIT_STACK, &stack_limit) == -1) {
PLOG(FATAL) << "getrlimit(RLIMIT_STACK) failed";
}
if (stack_limit.rlim_cur == RLIM_INFINITY) {
// Find the default stack size for new threads...
pthread_attr_t default_attributes;
size_t default_stack_size;
CHECK_PTHREAD_CALL(pthread_attr_init, (&default_attributes), "default stack size query");
CHECK_PTHREAD_CALL(pthread_attr_getstacksize, (&default_attributes, &default_stack_size),
"default stack size query");
CHECK_PTHREAD_CALL(pthread_attr_destroy, (&default_attributes), "default stack size query");
// ...and use that as our limit.
size_t old_stack_size = stack_size_;
stack_size_ = default_stack_size;
stack_begin_ += (old_stack_size - stack_size_);
VLOG(threads) << "Limiting unlimited stack (reported as " << PrettySize(old_stack_size) << ")"
<< " to " << PrettySize(stack_size_)
<< " with base " << reinterpret_cast<void*>(stack_begin_);
}
}
#endif
// Set stack_end_ to the bottom of the stack saving space of stack overflows
ResetDefaultStackEnd();
// Sanity check.
int stack_variable;
CHECK_GT(&stack_variable, reinterpret_cast<void*>(stack_end_));
}
void Thread::ShortDump(std::ostream& os) const {
os << "Thread[";
if (GetThinLockId() != 0) {
// If we're in kStarting, we won't have a thin lock id or tid yet.
os << GetThinLockId()
<< ",tid=" << GetTid() << ',';
}
os << GetState()
<< ",Thread*=" << this
<< ",peer=" << opeer_
<< ",\"" << *name_ << "\""
<< "]";
}
void Thread::Dump(std::ostream& os) const {
DumpState(os);
DumpStack(os);
}
String* Thread::GetThreadName(const ScopedObjectAccessUnchecked& soa) const {
Field* f = soa.DecodeField(WellKnownClasses::java_lang_Thread_name);
return (opeer_ != NULL) ? reinterpret_cast<String*>(f->GetObject(opeer_)) : NULL;
}
void Thread::GetThreadName(std::string& name) const {
name.assign(*name_);
}
void Thread::AtomicSetFlag(ThreadFlag flag) {
android_atomic_or(flag, &state_and_flags_.as_int);
}
void Thread::AtomicClearFlag(ThreadFlag flag) {
android_atomic_and(-1 ^ flag, &state_and_flags_.as_int);
}
ThreadState Thread::SetState(ThreadState new_state) {
// Cannot use this code to change into Runnable as changing to Runnable should fail if
// old_state_and_flags.suspend_request is true.
DCHECK_NE(new_state, kRunnable);
DCHECK_EQ(this, Thread::Current());
union StateAndFlags old_state_and_flags = state_and_flags_;
state_and_flags_.as_struct.state = new_state;
return static_cast<ThreadState>(old_state_and_flags.as_struct.state);
}
// 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()->DumpLocked(ss);
LOG(FATAL) << ss.str();
}
void Thread::ModifySuspendCount(Thread* self, int delta, bool for_debugger) {
DCHECK(delta == -1 || delta == +1 || delta == -debug_suspend_count_)
<< delta << " " << debug_suspend_count_ << " " << this;
DCHECK_GE(suspend_count_, 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 && suspend_count_ <= 0)) {
UnsafeLogFatalForSuspendCount(self, this);
return;
}
suspend_count_ += delta;
if (for_debugger) {
debug_suspend_count_ += delta;
}
if (suspend_count_ == 0) {
AtomicClearFlag(kSuspendRequest);
} else {
AtomicSetFlag(kSuspendRequest);
}
}
bool Thread::RequestCheckpoint(Closure* function) {
CHECK(!ReadFlag(kCheckpointRequest)) << "Already have a pending checkpoint request";
checkpoint_function_ = function;
union StateAndFlags old_state_and_flags = state_and_flags_;
// We must be runnable to request a checkpoint.
old_state_and_flags.as_struct.state = kRunnable;
union StateAndFlags new_state_and_flags = old_state_and_flags;
new_state_and_flags.as_struct.flags |= kCheckpointRequest;
int succeeded = android_atomic_cmpxchg(old_state_and_flags.as_int, new_state_and_flags.as_int,
&state_and_flags_.as_int);
return succeeded == 0;
}
void Thread::FullSuspendCheck() {
VLOG(threads) << this << " self-suspending";
// Make thread appear suspended to other threads, release mutator_lock_.
TransitionFromRunnableToSuspended(kSuspended);
// Transition back to runnable noting requests to suspend, re-acquire share on mutator_lock_.
TransitionFromSuspendedToRunnable();
VLOG(threads) << this << " self-reviving";
}
void Thread::TransitionFromRunnableToSuspended(ThreadState new_state) {
AssertThreadSuspensionIsAllowable();
DCHECK_NE(new_state, kRunnable);
DCHECK_EQ(this, Thread::Current());
// Change to non-runnable state, thereby appearing suspended to the system.
DCHECK_EQ(GetState(), kRunnable);
union StateAndFlags old_state_and_flags;
union StateAndFlags new_state_and_flags;
do {
old_state_and_flags = state_and_flags_;
// Copy over flags and try to clear the checkpoint bit if it is set.
new_state_and_flags.as_struct.flags = old_state_and_flags.as_struct.flags & ~kCheckpointRequest;
new_state_and_flags.as_struct.state = new_state;
} while (android_atomic_cmpxchg(old_state_and_flags.as_int, new_state_and_flags.as_int,
&state_and_flags_.as_int) != 0);
// If we toggled the checkpoint flag we must have cleared it.
uint16_t flag_change = new_state_and_flags.as_struct.flags ^ old_state_and_flags.as_struct.flags;
if ((flag_change & kCheckpointRequest) != 0) {
RunCheckpointFunction();
}
// Release share on mutator_lock_.
Locks::mutator_lock_->SharedUnlock(this);
}
ThreadState Thread::TransitionFromSuspendedToRunnable() {
bool done = false;
union StateAndFlags old_state_and_flags = state_and_flags_;
int16_t old_state = old_state_and_flags.as_struct.state;
DCHECK_NE(static_cast<ThreadState>(old_state), kRunnable);
do {
Locks::mutator_lock_->AssertNotHeld(this); // Otherwise we starve GC..
old_state_and_flags = state_and_flags_;
DCHECK_EQ(old_state_and_flags.as_struct.state, old_state);
if ((old_state_and_flags.as_struct.flags & kSuspendRequest) != 0) {
// Wait while our suspend count is non-zero.
MutexLock mu(this, *Locks::thread_suspend_count_lock_);
old_state_and_flags = state_and_flags_;
DCHECK_EQ(old_state_and_flags.as_struct.state, old_state);
while ((old_state_and_flags.as_struct.flags & kSuspendRequest) != 0) {
// Re-check when Thread::resume_cond_ is notified.
Thread::resume_cond_->Wait(this);
old_state_and_flags = state_and_flags_;
DCHECK_EQ(old_state_and_flags.as_struct.state, old_state);
}
DCHECK_EQ(GetSuspendCount(), 0);
}
// Re-acquire shared mutator_lock_ access.
Locks::mutator_lock_->SharedLock(this);
// Atomically change from suspended to runnable if no suspend request pending.
old_state_and_flags = state_and_flags_;
DCHECK_EQ(old_state_and_flags.as_struct.state, old_state);
if ((old_state_and_flags.as_struct.flags & kSuspendRequest) == 0) {
union StateAndFlags new_state_and_flags = old_state_and_flags;
new_state_and_flags.as_struct.state = kRunnable;
done = android_atomic_cmpxchg(old_state_and_flags.as_int, new_state_and_flags.as_int,
&state_and_flags_.as_int)
== 0;
}
if (!done) {
// Failed to transition to Runnable. Release shared mutator_lock_ access and try again.
Locks::mutator_lock_->SharedUnlock(this);
}
} while (!done);
return static_cast<ThreadState>(old_state);
}
Thread* Thread::SuspendForDebugger(jobject peer, bool request_suspension, bool* timeout) {
static const useconds_t kTimeoutUs = 30 * 1000000; // 30s.
useconds_t total_delay_us = 0;
useconds_t delay_us = 0;
bool did_suspend_request = false;
*timeout = false;
while (true) {
Thread* thread;
{
ScopedObjectAccess soa(Thread::Current());
MutexLock mu(soa.Self(), *Locks::thread_list_lock_);
thread = Thread::FromManagedThread(soa, peer);
if (thread == NULL) {
LOG(WARNING) << "No such thread for suspend: " << peer;
return NULL;
}
{
MutexLock mu(soa.Self(), *Locks::thread_suspend_count_lock_);
if (request_suspension) {
thread->ModifySuspendCount(soa.Self(), +1, true /* for_debugger */);
request_suspension = false;
did_suspend_request = true;
}
// IsSuspended on the current thread will fail as the current thread is changed into
// Runnable above. As the suspend count is now raised if this is the current thread
// it will self suspend on transition to Runnable, making it hard to work with. Its simpler
// to just explicitly handle the current thread in the callers to this code.
CHECK_NE(thread, soa.Self()) << "Attempt to suspend for debugger the current thread";
// If thread is suspended (perhaps it was already not Runnable but didn't have a suspend
// count, or else we've waited and it has self suspended) or is the current thread, we're
// done.
if (thread->IsSuspended()) {
return thread;
}
if (total_delay_us >= kTimeoutUs) {
LOG(ERROR) << "Thread suspension timed out: " << peer;
if (did_suspend_request) {
thread->ModifySuspendCount(soa.Self(), -1, true /* for_debugger */);
}
*timeout = true;
return NULL;
}
}
// Release locks and come out of runnable state.
}
for (int i = kMaxMutexLevel; i >= 0; --i) {
BaseMutex* held_mutex = Thread::Current()->GetHeldMutex(static_cast<LockLevel>(i));
if (held_mutex != NULL) {
LOG(FATAL) << "Holding " << held_mutex->GetName()
<< " while sleeping for thread suspension";
}
}
{
useconds_t new_delay_us = delay_us * 2;
CHECK_GE(new_delay_us, delay_us);
if (new_delay_us < 500000) { // Don't allow sleeping to be more than 0.5s.
delay_us = new_delay_us;
}
}
if (delay_us == 0) {
sched_yield();
// Default to 1 milliseconds (note that this gets multiplied by 2 before the first sleep).
delay_us = 500;
} else {
usleep(delay_us);
total_delay_us += delay_us;
}
}
}
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 (thread != NULL && thread->opeer_ != NULL) {
ScopedObjectAccessUnchecked soa(self);
priority = soa.DecodeField(WellKnownClasses::java_lang_Thread_priority)->GetInt(thread->opeer_);
is_daemon = soa.DecodeField(WellKnownClasses::java_lang_Thread_daemon)->GetBoolean(thread->opeer_);
Object* thread_group =
soa.DecodeField(WellKnownClasses::java_lang_Thread_group)->GetObject(thread->opeer_);
if (thread_group != NULL) {
Field* group_name_field = soa.DecodeField(WellKnownClasses::java_lang_ThreadGroup_name);
String* group_name_string = reinterpret_cast<String*>(group_name_field->GetObject(thread_group));
group_name = (group_name_string != NULL) ? 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 != NULL) {
os << '"' << *thread->name_ << '"';
if (is_daemon) {
os << " daemon";
}
os << " prio=" << priority
<< " tid=" << thread->GetThinLockId()
<< " " << thread->GetState() << "\n";
} else {
os << '"' << ::art::GetThreadName(tid) << '"'
<< " prio=" << priority
<< " (not attached)\n";
}
if (thread != NULL) {
MutexLock mu(self, *Locks::thread_suspend_count_lock_);
os << " | group=\"" << group_name << "\""
<< " sCount=" << thread->suspend_count_
<< " dsCount=" << thread->debug_suspend_count_
<< " obj=" << reinterpret_cast<void*>(thread->opeer_)
<< " self=" << reinterpret_cast<const void*>(thread) << "\n";
}
os << " | sysTid=" << tid
<< " nice=" << getpriority(PRIO_PROCESS, tid)
<< " cgrp=" << scheduler_group_name;
if (thread != NULL) {
int policy;
sched_param sp;
CHECK_PTHREAD_CALL(pthread_getschedparam, (thread->pthread_self_, &policy, &sp), __FUNCTION__);
os << " sched=" << policy << "/" << sp.sched_priority
<< " handle=" << reinterpret_cast<void*>(thread->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 != NULL) {
os << " | stack=" << reinterpret_cast<void*>(thread->stack_begin_) << "-" << reinterpret_cast<void*>(thread->stack_end_)
<< " stackSize=" << PrettySize(thread->stack_size_) << "\n";
}
}
void Thread::DumpState(std::ostream& os) const {
Thread::DumpState(os, this, GetTid());
}
struct StackDumpVisitor : public StackVisitor {
StackDumpVisitor(std::ostream& os, const Thread* thread, Context* context, bool can_allocate)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
: StackVisitor(thread->GetManagedStack(), thread->GetInstrumentationStack(), context),
os(os), thread(thread), can_allocate(can_allocate),
last_method(NULL), 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_) {
AbstractMethod* m = GetMethod();
if (m->IsRuntimeMethod()) {
return true;
}
const int kMaxRepetition = 3;
Class* c = m->GetDeclaringClass();
const DexCache* dex_cache = c->GetDexCache();
int line_number = -1;
if (dex_cache != NULL) { // be tolerant of bad input
const DexFile& dex_file = *dex_cache->GetDexFile();
line_number = dex_file.GetLineNumFromPC(m, GetDexPc());
}
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 {
mh.ChangeMethod(m);
const char* source_file(mh.GetDeclaringClassSourceFile());
os << "(" << (source_file != NULL ? source_file : "unavailable")
<< ":" << line_number << ")";
}
os << "\n";
if (frame_count == 0) {
Monitor::DescribeWait(os, thread);
}
if (can_allocate) {
Monitor::DescribeLocks(os, this);
}
}
++frame_count;
return true;
}
std::ostream& os;
const Thread* thread;
bool can_allocate;
MethodHelper mh;
AbstractMethod* last_method;
int last_line_number;
int repetition_count;
int frame_count;
};
void Thread::DumpStack(std::ostream& os) const {
// If we're currently in native code, dump that stack before dumping the managed stack.
if (GetState() == kNative) {
DumpKernelStack(os, GetTid(), " kernel: ", false);
DumpNativeStack(os, GetTid(), " native: ", false);
}
UniquePtr<Context> context(Context::Create());
StackDumpVisitor dumper(os, this, context.get(), !throwing_OutOfMemoryError_);
dumper.WalkStack();
}
void Thread::ThreadExitCallback(void* arg) {
Thread* self = reinterpret_cast<Thread*>(arg);
if (self->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_PTHREAD_CALL(pthread_setspecific, (Thread::pthread_key_self_, self), "reattach self");
self->thread_exit_check_count_ = 1;
} else {
LOG(FATAL) << "Native thread exited without calling DetachCurrentThread: " << *self;
}
}
void Thread::Startup() {
{
MutexLock mu(Thread::Current(), *Locks::thread_suspend_count_lock_); // Keep GCC happy.
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_) != NULL) {
LOG(FATAL) << "Newly-created pthread TLS slot is not NULL";
}
}
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());
Runtime::Current()->GetClassLinker()->RunRootClinits();
}
void Thread::Shutdown() {
CHECK_PTHREAD_CALL(pthread_key_delete, (Thread::pthread_key_self_), "self key");
}
Thread::Thread(bool daemon)
: suspend_count_(0),
card_table_(NULL),
exception_(NULL),
stack_end_(NULL),
managed_stack_(),
jni_env_(NULL),
self_(NULL),
opeer_(NULL),
jpeer_(NULL),
stack_begin_(NULL),
stack_size_(0),
thin_lock_id_(0),
tid_(0),
wait_mutex_(new Mutex("a thread wait mutex")),
wait_cond_(new ConditionVariable("a thread wait condition variable", *wait_mutex_)),
wait_monitor_(NULL),
interrupted_(false),
wait_next_(NULL),
monitor_enter_object_(NULL),
top_sirt_(NULL),
runtime_(NULL),
class_loader_override_(NULL),
long_jump_context_(NULL),
throwing_OutOfMemoryError_(false),
debug_suspend_count_(0),
debug_invoke_req_(new DebugInvokeReq),
instrumentation_stack_(new std::deque<InstrumentationStackFrame>),
name_(new std::string(kThreadNameDuringStartup)),
daemon_(daemon),
pthread_self_(0),
no_thread_suspension_(0),
last_no_thread_suspension_cause_(NULL),
checkpoint_function_(0),
thread_exit_check_count_(0) {
CHECK_EQ((sizeof(Thread) % 4), 0U) << sizeof(Thread);
state_and_flags_.as_struct.flags = 0;
state_and_flags_.as_struct.state = kNative;
memset(&held_mutexes_[0], 0, sizeof(held_mutexes_));
}
bool Thread::IsStillStarting() const {
// You might think you can check whether the state is kStarting, but for much of thread startup,
// the thread 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 (*name_ == kThreadNameDuringStartup);
}
void Thread::AssertNoPendingException() const {
if (UNLIKELY(IsExceptionPending())) {
ScopedObjectAccess soa(Thread::Current());
Throwable* exception = GetException();
LOG(FATAL) << "No pending exception expected: " << exception->Dump();
}
}
static void MonitorExitVisitor(const Object* object, void* arg) NO_THREAD_SAFETY_ANALYSIS {
Thread* self = reinterpret_cast<Thread*>(arg);
Object* entered_monitor = const_cast<Object*>(object);
if (self->HoldsLock(entered_monitor)) {
LOG(WARNING) << "Calling MonitorExit on object "
<< object << " (" << PrettyTypeOf(object) << ")"
<< " left locked by native thread "
<< *Thread::Current() << " which is detaching";
entered_monitor->MonitorExit(self);
}
}
void Thread::Destroy() {
Thread* self = this;
DCHECK_EQ(self, Thread::Current());
if (opeer_ != NULL) {
ScopedObjectAccess soa(self);
// We may need to call user-supplied managed code, do this before final clean-up.
HandleUncaughtExceptions(soa);
RemoveFromThreadGroup(soa);
// this.vmData = 0;
soa.DecodeField(WellKnownClasses::java_lang_Thread_vmData)->SetInt(opeer_, 0);
Dbg::PostThreadDeath(self);
// Thread.join() is implemented as an Object.wait() on the Thread.lock object. Signal anyone
// who is waiting.
Object* lock = soa.DecodeField(WellKnownClasses::java_lang_Thread_lock)->GetObject(opeer_);
// (This conditional is only needed for tests, where Thread.lock won't have been set.)
if (lock != NULL) {
lock->MonitorEnter(self);
lock->Notify();
lock->MonitorExit(self);
}
}
// On thread detach, all monitors entered with JNI MonitorEnter are automatically exited.
if (jni_env_ != NULL) {
jni_env_->monitors.VisitRoots(MonitorExitVisitor, self);
}
}
Thread::~Thread() {
if (jni_env_ != NULL && jpeer_ != NULL) {
// If pthread_create fails we don't have a jni env here.
jni_env_->DeleteGlobalRef(jpeer_);
jpeer_ = NULL;
}
opeer_ = NULL;
delete jni_env_;
jni_env_ = NULL;
CHECK_NE(GetState(), kRunnable);
// We may be deleting a still born thread.
SetStateUnsafe(kTerminated);
delete wait_cond_;
delete wait_mutex_;
#if !defined(ART_USE_LLVM_COMPILER)
delete long_jump_context_;
#endif
delete debug_invoke_req_;
delete instrumentation_stack_;
delete name_;
TearDownAlternateSignalStack();
}
void Thread::HandleUncaughtExceptions(ScopedObjectAccess& soa) {
if (!IsExceptionPending()) {
return;
}
ScopedLocalRef<jobject> peer(jni_env_, soa.AddLocalReference<jobject>(opeer_));
ScopedThreadStateChange tsc(this, kNative);
// Get and clear the exception.
ScopedLocalRef<jthrowable> exception(jni_env_, jni_env_->ExceptionOccurred());
jni_env_->ExceptionClear();
// If the thread has its own handler, use that.
ScopedLocalRef<jobject> handler(jni_env_,
jni_env_->GetObjectField(peer.get(),
WellKnownClasses::java_lang_Thread_uncaughtHandler));
if (handler.get() == NULL) {
// Otherwise use the thread group's default handler.
handler.reset(jni_env_->GetObjectField(peer.get(), WellKnownClasses::java_lang_Thread_group));
}
// Call the handler.
jni_env_->CallVoidMethod(handler.get(),
WellKnownClasses::java_lang_Thread$UncaughtExceptionHandler_uncaughtException,
peer.get(), exception.get());
// If the handler threw, clear that exception too.
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.
Object* ogroup = soa.DecodeField(WellKnownClasses::java_lang_Thread_group)->GetObject(opeer_);
if (ogroup != NULL) {
ScopedLocalRef<jobject> group(soa.Env(), soa.AddLocalReference<jobject>(ogroup));
ScopedLocalRef<jobject> peer(soa.Env(), soa.AddLocalReference<jobject>(opeer_));
ScopedThreadStateChange tsc(soa.Self(), kNative);
jni_env_->CallVoidMethod(group.get(), WellKnownClasses::java_lang_ThreadGroup_removeThread,
peer.get());
}
}
size_t Thread::NumSirtReferences() {
size_t count = 0;
for (StackIndirectReferenceTable* cur = top_sirt_; cur; cur = cur->GetLink()) {
count += cur->NumberOfReferences();
}
return count;
}
bool Thread::SirtContains(jobject obj) const {
Object** sirt_entry = reinterpret_cast<Object**>(obj);
for (StackIndirectReferenceTable* cur = top_sirt_; cur; cur = cur->GetLink()) {
if (cur->Contains(sirt_entry)) {
return true;
}
}
// JNI code invoked from portable code uses shadow frames rather than the SIRT.
return managed_stack_.ShadowFramesContain(sirt_entry);
}
void Thread::SirtVisitRoots(Heap::RootVisitor* visitor, void* arg) {
for (StackIndirectReferenceTable* cur = top_sirt_; cur; cur = cur->GetLink()) {
size_t num_refs = cur->NumberOfReferences();
for (size_t j = 0; j < num_refs; j++) {
Object* object = cur->GetReference(j);
if (object != NULL) {
visitor(object, arg);
}
}
}
}
Object* Thread::DecodeJObject(jobject obj) const {
Locks::mutator_lock_->AssertSharedHeld(this);
if (obj == NULL) {
return NULL;
}
IndirectRef ref = reinterpret_cast<IndirectRef>(obj);
IndirectRefKind kind = GetIndirectRefKind(ref);
Object* result;
switch (kind) {
case kLocal:
{
IndirectReferenceTable& locals = jni_env_->locals;
result = const_cast<Object*>(locals.Get(ref));
break;
}
case kGlobal:
{
JavaVMExt* vm = Runtime::Current()->GetJavaVM();
IndirectReferenceTable& globals = vm->globals;
MutexLock mu(const_cast<Thread*>(this), vm->globals_lock);
result = const_cast<Object*>(globals.Get(ref));
break;
}
case kWeakGlobal:
{
JavaVMExt* vm = Runtime::Current()->GetJavaVM();
IndirectReferenceTable& weak_globals = vm->weak_globals;
MutexLock mu(const_cast<Thread*>(this), vm->weak_globals_lock);
result = const_cast<Object*>(weak_globals.Get(ref));
if (result == kClearedJniWeakGlobal) {
// This is a special case where it's okay to return NULL.
return NULL;
}
break;
}
case kSirtOrInvalid:
default:
// TODO: make stack indirect reference table lookup more efficient
// Check if this is a local reference in the SIRT
if (SirtContains(obj)) {
result = *reinterpret_cast<Object**>(obj); // Read from SIRT
} else if (Runtime::Current()->GetJavaVM()->work_around_app_jni_bugs) {
// Assume an invalid local reference is actually a direct pointer.
result = reinterpret_cast<Object*>(obj);
} else {
result = kInvalidIndirectRefObject;
}
}
if (result == NULL) {
JniAbortF(NULL, "use of deleted %s %p", ToStr<IndirectRefKind>(kind).c_str(), obj);
} else {
if (result != kInvalidIndirectRefObject) {
Runtime::Current()->GetHeap()->VerifyObject(result);
}
}
return result;
}
// Implements java.lang.Thread.interrupted.
bool Thread::Interrupted() {
MutexLock mu(Thread::Current(), *wait_mutex_);
bool interrupted = interrupted_;
interrupted_ = false;
return interrupted;
}
// Implements java.lang.Thread.isInterrupted.
bool Thread::IsInterrupted() {
MutexLock mu(Thread::Current(), *wait_mutex_);
return interrupted_;
}
void Thread::Interrupt() {
Thread* self = Thread::Current();
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_ != NULL) {
wait_cond_->Signal(self);
}
}
class CountStackDepthVisitor : public StackVisitor {
public:
CountStackDepthVisitor(const ManagedStack* stack,
const std::deque<InstrumentationStackFrame>* instrumentation_stack)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
: StackVisitor(stack, instrumentation_stack, NULL),
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)
AbstractMethod* m = GetMethod();
if (skipping_ && !m->IsRuntimeMethod() &&
!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_;
};
class BuildInternalStackTraceVisitor : public StackVisitor {
public:
explicit BuildInternalStackTraceVisitor(Thread* self, const ManagedStack* stack,
const std::deque<InstrumentationStackFrame>* instrumentation_stack,
int skip_depth)
: StackVisitor(stack, instrumentation_stack, NULL), self_(self),
skip_depth_(skip_depth), count_(0), dex_pc_trace_(NULL), method_trace_(NULL) {}
bool Init(int depth)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
// Allocate method trace with an extra slot that will hold the PC trace
SirtRef<ObjectArray<Object> >
method_trace(self_,
Runtime::Current()->GetClassLinker()->AllocObjectArray<Object>(self_,
depth + 1));
if (method_trace.get() == NULL) {
return false;
}
IntArray* dex_pc_trace = IntArray::Alloc(self_, depth);
if (dex_pc_trace == NULL) {
return false;
}
// Save PC trace in last element of method trace, also places it into the
// object graph.
method_trace->Set(depth, dex_pc_trace);
// Set the Object*s and assert that no thread suspension is now possible.
const char* last_no_suspend_cause =
self_->StartAssertNoThreadSuspension("Building internal stack trace");
CHECK(last_no_suspend_cause == NULL) << last_no_suspend_cause;
method_trace_ = method_trace.get();
dex_pc_trace_ = dex_pc_trace;
return true;
}
virtual ~BuildInternalStackTraceVisitor() {
if (method_trace_ != NULL) {
self_->EndAssertNoThreadSuspension(NULL);
}
}
bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
if (method_trace_ == NULL || dex_pc_trace_ == NULL) {
return true; // We're probably trying to fillInStackTrace for an OutOfMemoryError.
}
if (skip_depth_ > 0) {
skip_depth_--;
return true;
}
AbstractMethod* m = GetMethod();
if (m->IsRuntimeMethod()) {
return true; // Ignore runtime frames (in particular callee save).
}
method_trace_->Set(count_, m);
dex_pc_trace_->Set(count_, GetDexPc());
++count_;
return true;
}
ObjectArray<Object>* GetInternalStackTrace() const {
return method_trace_;
}
private:
Thread* const self_;
// How many more frames to skip.
int32_t skip_depth_;
// Current position down stack trace.
uint32_t count_;
// Array of dex PC values.
IntArray* dex_pc_trace_;
// An array of the methods on the stack, the last entry is a reference to the PC trace.
ObjectArray<Object>* method_trace_;
};
jobject Thread::CreateInternalStackTrace(const ScopedObjectAccessUnchecked& soa) const {
// Compute depth of stack
CountStackDepthVisitor count_visitor(GetManagedStack(), GetInstrumentationStack());
count_visitor.WalkStack();
int32_t depth = count_visitor.GetDepth();
int32_t skip_depth = count_visitor.GetSkipDepth();
// Build internal stack trace.
BuildInternalStackTraceVisitor build_trace_visitor(soa.Self(), GetManagedStack(),
GetInstrumentationStack(), skip_depth);
if (!build_trace_visitor.Init(depth)) {
return NULL; // Allocation failed.
}
build_trace_visitor.WalkStack();
return soa.AddLocalReference<jobjectArray>(build_trace_visitor.GetInternalStackTrace());
}
jobjectArray Thread::InternalStackTraceToStackTraceElementArray(JNIEnv* env, jobject internal,
jobjectArray output_array, int* stack_depth) {
// Transition into runnable state to work on Object*/Array*
ScopedObjectAccess soa(env);
// Decode the internal stack trace into the depth, method trace and PC trace
ObjectArray<Object>* method_trace = soa.Decode<ObjectArray<Object>*>(internal);
int32_t depth = method_trace->GetLength() - 1;
IntArray* pc_trace = down_cast<IntArray*>(method_trace->Get(depth));
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
jobjectArray result;
ObjectArray<StackTraceElement>* java_traces;
if (output_array != NULL) {
// Reuse the array we were given.
result = output_array;
java_traces = soa.Decode<ObjectArray<StackTraceElement>*>(output_array);
// ...adjusting the number of frames we'll write to not exceed the array length.
depth = std::min(depth, java_traces->GetLength());
} else {
// Create java_trace array and place in local reference table
java_traces = class_linker->AllocStackTraceElementArray(soa.Self(), depth);
if (java_traces == NULL) {
return NULL;
}
result = soa.AddLocalReference<jobjectArray>(java_traces);
}
if (stack_depth != NULL) {
*stack_depth = depth;
}
MethodHelper mh;
for (int32_t i = 0; i < depth; ++i) {
// Prepare parameters for StackTraceElement(String cls, String method, String file, int line)
AbstractMethod* method = down_cast<AbstractMethod*>(method_trace->Get(i));
mh.ChangeMethod(method);
uint32_t dex_pc = pc_trace->Get(i);
int32_t line_number = mh.GetLineNumFromDexPC(dex_pc);
// Allocate element, potentially triggering GC
// TODO: reuse class_name_object via Class::name_?
const char* descriptor = mh.GetDeclaringClassDescriptor();
CHECK(descriptor != NULL);
std::string class_name(PrettyDescriptor(descriptor));
SirtRef<String> class_name_object(soa.Self(),
String::AllocFromModifiedUtf8(soa.Self(),
class_name.c_str()));
if (class_name_object.get() == NULL) {
return NULL;
}
const char* method_name = mh.GetName();
CHECK(method_name != NULL);
SirtRef<String> method_name_object(soa.Self(), String::AllocFromModifiedUtf8(soa.Self(),
method_name));
if (method_name_object.get() == NULL) {
return NULL;
}
const char* source_file = mh.GetDeclaringClassSourceFile();
SirtRef<String> source_name_object(soa.Self(), String::AllocFromModifiedUtf8(soa.Self(),
source_file));
StackTraceElement* obj = StackTraceElement::Alloc(soa.Self(),
class_name_object.get(),
method_name_object.get(),
source_name_object.get(),
line_number);
if (obj == NULL) {
return NULL;
}
#ifdef MOVING_GARBAGE_COLLECTOR
// Re-read after potential GC
java_traces = Decode<ObjectArray<Object>*>(soa.Env(), result);
method_trace = down_cast<ObjectArray<Object>*>(Decode<Object*>(soa.Env(), internal));
pc_trace = down_cast<IntArray*>(method_trace->Get(depth));
#endif
java_traces->Set(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) {
AssertNoPendingException(); // Callers should either clear or call ThrowNewWrappedException.
ThrowNewWrappedException(exception_class_descriptor, msg);
}
void Thread::ThrowNewWrappedException(const char* exception_class_descriptor, const char* msg) {
// Convert "Ljava/lang/Exception;" into JNI-style "java/lang/Exception".
CHECK_EQ('L', exception_class_descriptor[0]);
std::string descriptor(exception_class_descriptor + 1);
CHECK_EQ(';', descriptor[descriptor.length() - 1]);
descriptor.erase(descriptor.length() - 1);
JNIEnv* env = GetJniEnv();
jobject cause = env->ExceptionOccurred();
env->ExceptionClear();
ScopedLocalRef<jclass> exception_class(env, env->FindClass(descriptor.c_str()));
if (exception_class.get() == NULL) {
LOG(ERROR) << "Couldn't throw new " << descriptor << " because JNI FindClass failed: "
<< PrettyTypeOf(GetException());
CHECK(IsExceptionPending());
return;
}
if (!Runtime::Current()->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 use
// AllocObject which will not invoke a constructor.
ScopedLocalRef<jthrowable> exception(
env, reinterpret_cast<jthrowable>(env->AllocObject(exception_class.get())));
if (exception.get() != NULL) {
ScopedObjectAccessUnchecked soa(env);
Throwable* t = reinterpret_cast<Throwable*>(soa.Self()->DecodeJObject(exception.get()));
t->SetDetailMessage(String::AllocFromModifiedUtf8(soa.Self(), msg));
if (cause != NULL) {
t->SetCause(soa.Decode<Throwable*>(cause));
}
soa.Self()->SetException(t);
} else {
LOG(ERROR) << "Couldn't throw new " << descriptor << " because JNI AllocObject failed: "
<< PrettyTypeOf(GetException());
CHECK(IsExceptionPending());
}
return;
}
int rc = ::art::ThrowNewException(env, exception_class.get(), msg, cause);
if (rc != JNI_OK) {
LOG(ERROR) << "Couldn't throw new " << descriptor << " because JNI ThrowNew failed: "
<< PrettyTypeOf(GetException());
CHECK(IsExceptionPending());
}
}
void Thread::ThrowOutOfMemoryError(const char* msg) {
LOG(ERROR) << StringPrintf("Throwing OutOfMemoryError \"%s\"%s",
msg, (throwing_OutOfMemoryError_ ? " (recursive case)" : ""));
if (!throwing_OutOfMemoryError_) {
throwing_OutOfMemoryError_ = true;
ThrowNewException("Ljava/lang/OutOfMemoryError;", msg);
} else {
Dump(LOG(ERROR)); // The pre-allocated OOME has no stack, so help out and log one.
SetException(Runtime::Current()->GetPreAllocatedOutOfMemoryError());
}
throwing_OutOfMemoryError_ = false;
}
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
}
struct EntryPointInfo {
uint32_t offset;
const char* name;
};
#define ENTRY_POINT_INFO(x) { ENTRYPOINT_OFFSET(x), #x }
static const EntryPointInfo gThreadEntryPointInfo[] = {
ENTRY_POINT_INFO(pAllocArrayFromCode),
ENTRY_POINT_INFO(pAllocArrayFromCodeWithAccessCheck),
ENTRY_POINT_INFO(pAllocObjectFromCode),
ENTRY_POINT_INFO(pAllocObjectFromCodeWithAccessCheck),
ENTRY_POINT_INFO(pCheckAndAllocArrayFromCode),
ENTRY_POINT_INFO(pCheckAndAllocArrayFromCodeWithAccessCheck),
ENTRY_POINT_INFO(pInstanceofNonTrivialFromCode),
ENTRY_POINT_INFO(pCanPutArrayElementFromCode),
ENTRY_POINT_INFO(pCheckCastFromCode),
ENTRY_POINT_INFO(pDebugMe),
ENTRY_POINT_INFO(pUpdateDebuggerFromCode),
ENTRY_POINT_INFO(pInitializeStaticStorage),
ENTRY_POINT_INFO(pInitializeTypeAndVerifyAccessFromCode),
ENTRY_POINT_INFO(pInitializeTypeFromCode),
ENTRY_POINT_INFO(pResolveStringFromCode),
ENTRY_POINT_INFO(pGetAndClearException),
ENTRY_POINT_INFO(pSet32Instance),
ENTRY_POINT_INFO(pSet32Static),
ENTRY_POINT_INFO(pSet64Instance),
ENTRY_POINT_INFO(pSet64Static),
ENTRY_POINT_INFO(pSetObjInstance),
ENTRY_POINT_INFO(pSetObjStatic),
ENTRY_POINT_INFO(pGet32Instance),
ENTRY_POINT_INFO(pGet32Static),
ENTRY_POINT_INFO(pGet64Instance),
ENTRY_POINT_INFO(pGet64Static),
ENTRY_POINT_INFO(pGetObjInstance),
ENTRY_POINT_INFO(pGetObjStatic),
ENTRY_POINT_INFO(pHandleFillArrayDataFromCode),
ENTRY_POINT_INFO(pFindNativeMethod),
ENTRY_POINT_INFO(pJniMethodStart),
ENTRY_POINT_INFO(pJniMethodStartSynchronized),
ENTRY_POINT_INFO(pJniMethodEnd),
ENTRY_POINT_INFO(pJniMethodEndSynchronized),
ENTRY_POINT_INFO(pJniMethodEndWithReference),
ENTRY_POINT_INFO(pJniMethodEndWithReferenceSynchronized),
ENTRY_POINT_INFO(pLockObjectFromCode),
ENTRY_POINT_INFO(pUnlockObjectFromCode),
ENTRY_POINT_INFO(pCmpgDouble),
ENTRY_POINT_INFO(pCmpgFloat),
ENTRY_POINT_INFO(pCmplDouble),
ENTRY_POINT_INFO(pCmplFloat),
ENTRY_POINT_INFO(pFmod),
ENTRY_POINT_INFO(pSqrt),
ENTRY_POINT_INFO(pL2d),
ENTRY_POINT_INFO(pFmodf),
ENTRY_POINT_INFO(pL2f),
ENTRY_POINT_INFO(pD2iz),
ENTRY_POINT_INFO(pF2iz),
ENTRY_POINT_INFO(pIdivmod),
ENTRY_POINT_INFO(pD2l),
ENTRY_POINT_INFO(pF2l),
ENTRY_POINT_INFO(pLdiv),
ENTRY_POINT_INFO(pLdivmod),
ENTRY_POINT_INFO(pLmul),
ENTRY_POINT_INFO(pShlLong),
ENTRY_POINT_INFO(pShrLong),
ENTRY_POINT_INFO(pUshrLong),
ENTRY_POINT_INFO(pIndexOf),
ENTRY_POINT_INFO(pMemcmp16),
ENTRY_POINT_INFO(pStringCompareTo),
ENTRY_POINT_INFO(pMemcpy),
ENTRY_POINT_INFO(pUnresolvedDirectMethodTrampolineFromCode),
ENTRY_POINT_INFO(pInvokeDirectTrampolineWithAccessCheck),
ENTRY_POINT_INFO(pInvokeInterfaceTrampoline),
ENTRY_POINT_INFO(pInvokeInterfaceTrampolineWithAccessCheck),
ENTRY_POINT_INFO(pInvokeStaticTrampolineWithAccessCheck),
ENTRY_POINT_INFO(pInvokeSuperTrampolineWithAccessCheck),
ENTRY_POINT_INFO(pInvokeVirtualTrampolineWithAccessCheck),
ENTRY_POINT_INFO(pCheckSuspendFromCode),
ENTRY_POINT_INFO(pTestSuspendFromCode),
ENTRY_POINT_INFO(pDeliverException),
ENTRY_POINT_INFO(pThrowAbstractMethodErrorFromCode),
ENTRY_POINT_INFO(pThrowArrayBoundsFromCode),
ENTRY_POINT_INFO(pThrowDivZeroFromCode),
ENTRY_POINT_INFO(pThrowNoSuchMethodFromCode),
ENTRY_POINT_INFO(pThrowNullPointerFromCode),
ENTRY_POINT_INFO(pThrowStackOverflowFromCode),
};
#undef ENTRY_POINT_INFO
void Thread::DumpThreadOffset(std::ostream& os, uint32_t offset, size_t size_of_pointers) {
CHECK_EQ(size_of_pointers, 4U); // TODO: support 64-bit targets.
#define DO_THREAD_OFFSET(x) if (offset == static_cast<uint32_t>(OFFSETOF_VOLATILE_MEMBER(Thread, x))) { os << # x; return; }
DO_THREAD_OFFSET(state_and_flags_);
DO_THREAD_OFFSET(card_table_);
DO_THREAD_OFFSET(exception_);
DO_THREAD_OFFSET(opeer_);
DO_THREAD_OFFSET(jni_env_);
DO_THREAD_OFFSET(self_);
DO_THREAD_OFFSET(stack_end_);
DO_THREAD_OFFSET(suspend_count_);
DO_THREAD_OFFSET(thin_lock_id_);
//DO_THREAD_OFFSET(top_of_managed_stack_);
//DO_THREAD_OFFSET(top_of_managed_stack_pc_);
DO_THREAD_OFFSET(top_sirt_);
#undef DO_THREAD_OFFSET
size_t entry_point_count = arraysize(gThreadEntryPointInfo);
CHECK_EQ(entry_point_count * size_of_pointers, sizeof(EntryPoints));
uint32_t expected_offset = OFFSETOF_MEMBER(Thread, entrypoints_);
for (size_t i = 0; i < entry_point_count; ++i) {
CHECK_EQ(gThreadEntryPointInfo[i].offset, expected_offset) << gThreadEntryPointInfo[i].name;
expected_offset += size_of_pointers;
if (gThreadEntryPointInfo[i].offset == offset) {
os << gThreadEntryPointInfo[i].name;
return;
}
}
os << offset;
}
static const bool kDebugExceptionDelivery = false;
class CatchBlockStackVisitor : public StackVisitor {
public:
CatchBlockStackVisitor(Thread* self, Throwable* exception)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
: StackVisitor(self->GetManagedStack(), self->GetInstrumentationStack(), self->GetLongJumpContext()),
self_(self), exception_(exception), to_find_(exception->GetClass()), throw_method_(NULL),
throw_frame_id_(0), throw_dex_pc_(0), handler_quick_frame_(NULL),
handler_quick_frame_pc_(0), handler_dex_pc_(0), native_method_count_(0),
method_tracing_active_(Runtime::Current()->IsMethodTracingActive()) {
// Exception not in root sets, can't allow GC.
last_no_assert_suspension_cause_ = self->StartAssertNoThreadSuspension("Finding catch block");
}
~CatchBlockStackVisitor() {
LOG(FATAL) << "UNREACHABLE"; // Expected to take long jump.
}
bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
AbstractMethod* method = GetMethod();
if (method == NULL) {
// This is the upcall, we remember the frame and last pc so that we may long jump to them.
handler_quick_frame_pc_ = GetCurrentQuickFramePc();
handler_quick_frame_ = GetCurrentQuickFrame();
return false; // End stack walk.
}
uint32_t dex_pc = DexFile::kDexNoIndex;
if (method->IsRuntimeMethod()) {
// ignore callee save method
DCHECK(method->IsCalleeSaveMethod());
} else {
if (throw_method_ == NULL) {
throw_method_ = method;
throw_frame_id_ = GetFrameId();
throw_dex_pc_ = GetDexPc();
}
if (method->IsNative()) {
native_method_count_++;
} else {
// Unwind stack when an exception occurs during instrumentation
if (UNLIKELY(method_tracing_active_ &&
GetInstrumentationExitPc() == GetCurrentQuickFramePc())) {
uintptr_t pc = InstrumentationMethodUnwindFromCode(Thread::Current());
dex_pc = method->ToDexPc(pc);
} else {
dex_pc = GetDexPc();
}
}
}
if (dex_pc != DexFile::kDexNoIndex) {
uint32_t found_dex_pc = method->FindCatchBlock(to_find_, dex_pc);
if (found_dex_pc != DexFile::kDexNoIndex) {
handler_dex_pc_ = found_dex_pc;
handler_quick_frame_pc_ = method->ToNativePc(found_dex_pc);
handler_quick_frame_ = GetCurrentQuickFrame();
return false; // End stack walk.
}
}
return true; // Continue stack walk.
}
void DoLongJump() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
AbstractMethod* catch_method = *handler_quick_frame_;
if (kDebugExceptionDelivery) {
if (catch_method == NULL) {
LOG(INFO) << "Handler is upcall";
} else {
const DexFile& dex_file = *catch_method->GetDeclaringClass()->GetDexCache()->GetDexFile();
int line_number = dex_file.GetLineNumFromPC(catch_method, handler_dex_pc_);
LOG(INFO) << "Handler: " << PrettyMethod(catch_method) << " (line: " << line_number << ")";
}
}
self_->SetException(exception_); // Exception back in root set.
self_->EndAssertNoThreadSuspension(last_no_assert_suspension_cause_);
// Do debugger PostException after allowing thread suspension again.
Dbg::PostException(self_, throw_frame_id_, throw_method_, throw_dex_pc_,
catch_method, handler_dex_pc_, exception_);
// Place context back on thread so it will be available when we continue.
self_->ReleaseLongJumpContext(context_);
context_->SetSP(reinterpret_cast<uintptr_t>(handler_quick_frame_));
CHECK_NE(handler_quick_frame_pc_, 0u);
context_->SetPC(handler_quick_frame_pc_);
context_->SmashCallerSaves();
context_->DoLongJump();
}
private:
Thread* self_;
Throwable* exception_;
// The type of the exception catch block to find.
Class* to_find_;
AbstractMethod* throw_method_;
JDWP::FrameId throw_frame_id_;
uint32_t throw_dex_pc_;
// Quick frame with found handler or last frame if no handler found.
AbstractMethod** handler_quick_frame_;
// PC to branch to for the handler.
uintptr_t handler_quick_frame_pc_;
// Associated dex PC.
uint32_t handler_dex_pc_;
// Number of native methods passed in crawl (equates to number of SIRTs to pop)
uint32_t native_method_count_;
// Is method tracing active?
const bool method_tracing_active_;
// Support for nesting no thread suspension checks.
const char* last_no_assert_suspension_cause_;
};
void Thread::QuickDeliverException() {
Throwable* exception = GetException(); // Get exception from thread
CHECK(exception != NULL);
// Don't leave exception visible while we try to find the handler, which may cause class
// resolution.
ClearException();
if (kDebugExceptionDelivery) {
String* msg = exception->GetDetailMessage();
std::string str_msg(msg != NULL ? msg->ToModifiedUtf8() : "");
DumpStack(LOG(INFO) << "Delivering exception: " << PrettyTypeOf(exception)
<< ": " << str_msg << "\n");
}
CatchBlockStackVisitor catch_finder(this, exception);
catch_finder.WalkStack(true);
catch_finder.DoLongJump();
LOG(FATAL) << "UNREACHABLE";
}
Context* Thread::GetLongJumpContext() {
Context* result = long_jump_context_;
if (result == NULL) {
result = Context::Create();
} else {
long_jump_context_ = NULL; // Avoid context being shared.
result->Reset();
}
return result;
}
AbstractMethod* Thread::GetCurrentMethod(uint32_t* dex_pc, size_t* frame_id) const {
struct CurrentMethodVisitor : public StackVisitor {
CurrentMethodVisitor(const ManagedStack* stack,
const std::deque<InstrumentationStackFrame>* instrumentation_stack)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
: StackVisitor(stack, instrumentation_stack, NULL), method_(NULL), dex_pc_(0), frame_id_(0) {}
virtual bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
AbstractMethod* m = GetMethod();
if (m->IsRuntimeMethod()) {
// Continue if this is a runtime method.
return true;
}
method_ = m;
dex_pc_ = GetDexPc();
frame_id_ = GetFrameId();
return false;
}
AbstractMethod* method_;
uint32_t dex_pc_;
size_t frame_id_;
};
CurrentMethodVisitor visitor(GetManagedStack(), GetInstrumentationStack());
visitor.WalkStack(false);
if (dex_pc != NULL) {
*dex_pc = visitor.dex_pc_;
}
if (frame_id != NULL) {
*frame_id = visitor.frame_id_;
}
return visitor.method_;
}
bool Thread::HoldsLock(Object* object) {
if (object == NULL) {
return false;
}
return object->GetThinLockId() == thin_lock_id_;
}
// RootVisitor parameters are: (const Object* obj, size_t vreg, const StackVisitor* visitor).
template <typename RootVisitor>
class ReferenceMapVisitor : public StackVisitor {
public:
ReferenceMapVisitor(const ManagedStack* stack,
const std::deque<InstrumentationStackFrame>* instrumentation_stack,
Context* context, const RootVisitor& visitor)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
: StackVisitor(stack, instrumentation_stack, context), 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 != NULL) {
AbstractMethod* m = shadow_frame->GetMethod();
size_t num_regs = shadow_frame->NumberOfVRegs();
if (m->IsNative() || shadow_frame->HasReferenceArray()) {
// SIRT for JNI or References for interpreter.
for (size_t reg = 0; reg < num_regs; ++reg) {
Object* ref = shadow_frame->GetVRegReference(reg);
if (ref != NULL) {
visitor_(ref, reg, this);
}
}
} else {
// Java method.
// Portable path use DexGcMap and store in Method.native_gc_map_.
const uint8_t* gc_map = m->GetNativeGcMap();
CHECK(gc_map != NULL) << PrettyMethod(m);
uint32_t gc_map_length = static_cast<uint32_t>((gc_map[0] << 24) |
(gc_map[1] << 16) |
(gc_map[2] << 8) |
(gc_map[3] << 0));
verifier::DexPcToReferenceMap dex_gc_map(gc_map + 4, gc_map_length);
uint32_t dex_pc = GetDexPc();
const uint8_t* reg_bitmap = dex_gc_map.FindBitMap(dex_pc);
DCHECK(reg_bitmap != NULL);
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)) {
Object* ref = shadow_frame->GetVRegReference(reg);
if (ref != NULL) {
visitor_(ref, reg, this);
}
}
}
}
} else {
AbstractMethod* m = GetMethod();
// Process register map (which native and runtime methods don't have)
if (!m->IsNative() && !m->IsRuntimeMethod() && !m->IsProxyMethod()) {
const uint8_t* native_gc_map = m->GetNativeGcMap();
CHECK(native_gc_map != NULL) << PrettyMethod(m);
mh_.ChangeMethod(m);
const DexFile::CodeItem* code_item = mh_.GetCodeItem();
DCHECK(code_item != NULL) << PrettyMethod(m); // Can't be NULL or how would we compile its instructions?
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) {
const uint8_t* reg_bitmap = map.FindBitMap(GetNativePcOffset());
DCHECK(reg_bitmap != NULL);
const VmapTable vmap_table(m->GetVmapTableRaw());
uint32_t core_spills = m->GetCoreSpillMask();
uint32_t fp_spills = m->GetFpSpillMask();
size_t frame_size = m->GetFrameSizeInBytes();
// For all dex registers in the bitmap
AbstractMethod** cur_quick_frame = GetCurrentQuickFrame();
DCHECK(cur_quick_frame != NULL);
for (size_t reg = 0; reg < num_regs; ++reg) {
// Does this register hold a reference?
if (TestBitmap(reg, reg_bitmap)) {
uint32_t vmap_offset;
Object* ref;
if (vmap_table.IsInContext(reg, vmap_offset, kReferenceVReg)) {
uintptr_t val = GetGPR(vmap_table.ComputeRegister(core_spills, vmap_offset,
kReferenceVReg));
ref = reinterpret_cast<Object*>(val);
} else {
ref = reinterpret_cast<Object*>(GetVReg(cur_quick_frame, code_item, core_spills,
fp_spills, frame_size, reg));
}
if (ref != NULL) {
visitor_(ref, reg, this);
}
}
}
}
}
}
return true;
}
private:
static bool TestBitmap(int reg, const uint8_t* reg_vector) {
return ((reg_vector[reg / 8] >> (reg % 8)) & 0x01) != 0;
}
// Visitor for when we visit a root.
const RootVisitor& visitor_;
// A method helper we keep around to avoid dex file/cache re-computations.
MethodHelper mh_;
};
class RootCallbackVisitor {
public:
RootCallbackVisitor(Heap::RootVisitor* visitor, void* arg) : visitor_(visitor), arg_(arg) {
}
void operator()(const Object* obj, size_t, const StackVisitor*) const {
visitor_(obj, arg_);
}
private:
Heap::RootVisitor* visitor_;
void* arg_;
};
class VerifyCallbackVisitor {
public:
VerifyCallbackVisitor(Heap::VerifyRootVisitor* visitor, void* arg)
: visitor_(visitor),
arg_(arg) {
}
void operator()(const Object* obj, size_t vreg, const StackVisitor* visitor) const {
visitor_(obj, arg_, vreg, visitor);
}
private:
Heap::VerifyRootVisitor* const visitor_;
void* const arg_;
};
struct VerifyRootWrapperArg {
Heap::VerifyRootVisitor* visitor;
void* arg;
};
static void VerifyRootWrapperCallback(const Object* root, void* arg) {
VerifyRootWrapperArg* wrapperArg = reinterpret_cast<VerifyRootWrapperArg*>(arg);
wrapperArg->visitor(root, wrapperArg->arg, 0, NULL);
}
void Thread::VerifyRoots(Heap::VerifyRootVisitor* visitor, void* arg) {
// We need to map from a RootVisitor to VerifyRootVisitor, so pass in nulls for arguments we
// don't have.
VerifyRootWrapperArg wrapperArg;
wrapperArg.arg = arg;
wrapperArg.visitor = visitor;
if (opeer_ != NULL) {
VerifyRootWrapperCallback(opeer_, &wrapperArg);
}
if (exception_ != NULL) {
VerifyRootWrapperCallback(exception_, &wrapperArg);
}
if (class_loader_override_ != NULL) {
VerifyRootWrapperCallback(class_loader_override_, &wrapperArg);
}
jni_env_->locals.VisitRoots(VerifyRootWrapperCallback, &wrapperArg);
jni_env_->monitors.VisitRoots(VerifyRootWrapperCallback, &wrapperArg);
SirtVisitRoots(VerifyRootWrapperCallback, &wrapperArg);
// Visit roots on this thread's stack
Context* context = GetLongJumpContext();
VerifyCallbackVisitor visitorToCallback(visitor, arg);
ReferenceMapVisitor<VerifyCallbackVisitor> mapper(GetManagedStack(), GetInstrumentationStack(),
context, visitorToCallback);
mapper.WalkStack();
ReleaseLongJumpContext(context);
}
void Thread::VisitRoots(Heap::RootVisitor* visitor, void* arg) {
if (opeer_ != NULL) {
visitor(opeer_, arg);
}
if (exception_ != NULL) {
visitor(exception_, arg);
}
if (class_loader_override_ != NULL) {
visitor(class_loader_override_, arg);
}
jni_env_->locals.VisitRoots(visitor, arg);
jni_env_->monitors.VisitRoots(visitor, arg);
SirtVisitRoots(visitor, arg);
// Visit roots on this thread's stack
Context* context = GetLongJumpContext();
RootCallbackVisitor visitorToCallback(visitor, arg);
ReferenceMapVisitor<RootCallbackVisitor> mapper(GetManagedStack(), GetInstrumentationStack(), context,
visitorToCallback);
mapper.WalkStack();
ReleaseLongJumpContext(context);
}
#if VERIFY_OBJECT_ENABLED
static void VerifyObject(const Object* obj, void* arg) {
Heap* heap = reinterpret_cast<Heap*>(arg);
heap->VerifyObject(obj);
}
void Thread::VerifyStack() {
UniquePtr<Context> context(Context::Create());
RootCallbackVisitor visitorToCallback(VerifyObject, Runtime::Current()->GetHeap());
ReferenceMapVisitor<RootCallbackVisitor> mapper(GetManagedStack(), GetInstrumentationStack(), context.get(),
visitorToCallback);
mapper.WalkStack();
}
#endif
// 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 (stack_end_ == stack_begin_) {
DumpStack(std::cerr);
LOG(FATAL) << "Need to increase kStackOverflowReservedBytes (currently "
<< kStackOverflowReservedBytes << ")";
}
stack_end_ = stack_begin_;
}
std::ostream& operator<<(std::ostream& os, const Thread& thread) {
thread.ShortDump(os);
return os;
}
#ifndef NDEBUG
void Thread::AssertThreadSuspensionIsAllowable(bool check_locks) const {
CHECK_EQ(0u, no_thread_suspension_) << last_no_thread_suspension_cause_;
if (check_locks) {
bool bad_mutexes_held = false;
for (int i = kMaxMutexLevel; i >= 0; --i) {
// We expect no locks except the mutator_lock_.
if (i != kMutatorLock) {
BaseMutex* held_mutex = GetHeldMutex(static_cast<LockLevel>(i));
if (held_mutex != NULL) {
LOG(ERROR) << "holding \"" << held_mutex->GetName()
<< "\" at point where thread suspension is expected";
bad_mutexes_held = true;
}
}
}
CHECK(!bad_mutexes_held);
}
}
#endif
} // namespace art