thread.cc revision b0fa5dc7769c1e054032f39de0a3f6d6dd06f8cf
1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define ATRACE_TAG ATRACE_TAG_DALVIK
18
19#include "thread.h"
20
21#include <cutils/trace.h>
22#include <pthread.h>
23#include <signal.h>
24#include <sys/resource.h>
25#include <sys/time.h>
26
27#include <algorithm>
28#include <bitset>
29#include <cerrno>
30#include <iostream>
31#include <list>
32
33#include "arch/context.h"
34#include "base/mutex.h"
35#include "class_linker.h"
36#include "class_linker-inl.h"
37#include "cutils/atomic.h"
38#include "cutils/atomic-inline.h"
39#include "debugger.h"
40#include "dex_file-inl.h"
41#include "entrypoints/entrypoint_utils.h"
42#include "entrypoints/quick/quick_alloc_entrypoints.h"
43#include "gc_map.h"
44#include "gc/accounting/card_table-inl.h"
45#include "gc/heap.h"
46#include "gc/space/space.h"
47#include "jni_internal.h"
48#include "mirror/art_field-inl.h"
49#include "mirror/art_method-inl.h"
50#include "mirror/class-inl.h"
51#include "mirror/class_loader.h"
52#include "mirror/object_array-inl.h"
53#include "mirror/stack_trace_element.h"
54#include "monitor.h"
55#include "object_utils.h"
56#include "quick_exception_handler.h"
57#include "reflection.h"
58#include "runtime.h"
59#include "scoped_thread_state_change.h"
60#include "ScopedLocalRef.h"
61#include "ScopedUtfChars.h"
62#include "sirt_ref.h"
63#include "stack.h"
64#include "stack_indirect_reference_table.h"
65#include "thread-inl.h"
66#include "thread_list.h"
67#include "utils.h"
68#include "verifier/dex_gc_map.h"
69#include "verify_object-inl.h"
70#include "vmap_table.h"
71#include "well_known_classes.h"
72
73namespace art {
74
75bool Thread::is_started_ = false;
76pthread_key_t Thread::pthread_key_self_;
77ConditionVariable* Thread::resume_cond_ = nullptr;
78
79static const char* kThreadNameDuringStartup = "<native thread without managed peer>";
80
81void Thread::InitCardTable() {
82  tlsPtr_.card_table = Runtime::Current()->GetHeap()->GetCardTable()->GetBiasedBegin();
83}
84
85static void UnimplementedEntryPoint() {
86  UNIMPLEMENTED(FATAL);
87}
88
89void InitEntryPoints(InterpreterEntryPoints* ipoints, JniEntryPoints* jpoints,
90                     PortableEntryPoints* ppoints, QuickEntryPoints* qpoints);
91
92void Thread::InitTlsEntryPoints() {
93  // Insert a placeholder so we can easily tell if we call an unimplemented entry point.
94  uintptr_t* begin = reinterpret_cast<uintptr_t*>(&tlsPtr_.interpreter_entrypoints);
95  uintptr_t* end = reinterpret_cast<uintptr_t*>(reinterpret_cast<uint8_t*>(begin) +
96                                                sizeof(tlsPtr_.quick_entrypoints));
97  for (uintptr_t* it = begin; it != end; ++it) {
98    *it = reinterpret_cast<uintptr_t>(UnimplementedEntryPoint);
99  }
100  InitEntryPoints(&tlsPtr_.interpreter_entrypoints, &tlsPtr_.jni_entrypoints,
101                  &tlsPtr_.portable_entrypoints, &tlsPtr_.quick_entrypoints);
102}
103
104void Thread::ResetQuickAllocEntryPointsForThread() {
105  ResetQuickAllocEntryPoints(&tlsPtr_.quick_entrypoints);
106}
107
108void Thread::SetDeoptimizationShadowFrame(ShadowFrame* sf) {
109  tlsPtr_.deoptimization_shadow_frame = sf;
110}
111
112void Thread::SetDeoptimizationReturnValue(const JValue& ret_val) {
113  tls64_.deoptimization_return_value.SetJ(ret_val.GetJ());
114}
115
116ShadowFrame* Thread::GetAndClearDeoptimizationShadowFrame(JValue* ret_val) {
117  ShadowFrame* sf = tlsPtr_.deoptimization_shadow_frame;
118  tlsPtr_.deoptimization_shadow_frame = nullptr;
119  ret_val->SetJ(tls64_.deoptimization_return_value.GetJ());
120  return sf;
121}
122
123void Thread::InitTid() {
124  tls32_.tid = ::art::GetTid();
125}
126
127void Thread::InitAfterFork() {
128  // One thread (us) survived the fork, but we have a new tid so we need to
129  // update the value stashed in this Thread*.
130  InitTid();
131}
132
133void* Thread::CreateCallback(void* arg) {
134  Thread* self = reinterpret_cast<Thread*>(arg);
135  Runtime* runtime = Runtime::Current();
136  if (runtime == nullptr) {
137    LOG(ERROR) << "Thread attaching to non-existent runtime: " << *self;
138    return nullptr;
139  }
140  {
141    // TODO: pass self to MutexLock - requires self to equal Thread::Current(), which is only true
142    //       after self->Init().
143    MutexLock mu(nullptr, *Locks::runtime_shutdown_lock_);
144    // Check that if we got here we cannot be shutting down (as shutdown should never have started
145    // while threads are being born).
146    CHECK(!runtime->IsShuttingDownLocked());
147    self->Init(runtime->GetThreadList(), runtime->GetJavaVM());
148    Runtime::Current()->EndThreadBirth();
149  }
150  {
151    ScopedObjectAccess soa(self);
152
153    // Copy peer into self, deleting global reference when done.
154    CHECK(self->tlsPtr_.jpeer != nullptr);
155    self->tlsPtr_.opeer = soa.Decode<mirror::Object*>(self->tlsPtr_.jpeer);
156    self->GetJniEnv()->DeleteGlobalRef(self->tlsPtr_.jpeer);
157    self->tlsPtr_.jpeer = nullptr;
158
159    {
160      SirtRef<mirror::String> thread_name(self, self->GetThreadName(soa));
161      self->SetThreadName(thread_name->ToModifiedUtf8().c_str());
162    }
163    Dbg::PostThreadStart(self);
164
165    // Invoke the 'run' method of our java.lang.Thread.
166    mirror::Object* receiver = self->tlsPtr_.opeer;
167    jmethodID mid = WellKnownClasses::java_lang_Thread_run;
168    InvokeVirtualOrInterfaceWithJValues(soa, receiver, mid, nullptr);
169  }
170  // Detach and delete self.
171  Runtime::Current()->GetThreadList()->Unregister(self);
172
173  return nullptr;
174}
175
176Thread* Thread::FromManagedThread(const ScopedObjectAccessUnchecked& soa,
177                                  mirror::Object* thread_peer) {
178  mirror::ArtField* f = soa.DecodeField(WellKnownClasses::java_lang_Thread_nativePeer);
179  Thread* result = reinterpret_cast<Thread*>(static_cast<uintptr_t>(f->GetLong(thread_peer)));
180  // Sanity check that if we have a result it is either suspended or we hold the thread_list_lock_
181  // to stop it from going away.
182  if (kIsDebugBuild) {
183    MutexLock mu(soa.Self(), *Locks::thread_suspend_count_lock_);
184    if (result != nullptr && !result->IsSuspended()) {
185      Locks::thread_list_lock_->AssertHeld(soa.Self());
186    }
187  }
188  return result;
189}
190
191Thread* Thread::FromManagedThread(const ScopedObjectAccessUnchecked& soa, jobject java_thread) {
192  return FromManagedThread(soa, soa.Decode<mirror::Object*>(java_thread));
193}
194
195static size_t FixStackSize(size_t stack_size) {
196  // A stack size of zero means "use the default".
197  if (stack_size == 0) {
198    stack_size = Runtime::Current()->GetDefaultStackSize();
199  }
200
201  // Dalvik used the bionic pthread default stack size for native threads,
202  // so include that here to support apps that expect large native stacks.
203  stack_size += 1 * MB;
204
205  // It's not possible to request a stack smaller than the system-defined PTHREAD_STACK_MIN.
206  if (stack_size < PTHREAD_STACK_MIN) {
207    stack_size = PTHREAD_STACK_MIN;
208  }
209
210  if (Runtime::Current()->ExplicitStackOverflowChecks()) {
211    // It's likely that callers are trying to ensure they have at least a certain amount of
212    // stack space, so we should add our reserved space on top of what they requested, rather
213    // than implicitly take it away from them.
214    stack_size += Thread::kStackOverflowReservedBytes;
215  } else {
216    // If we are going to use implicit stack checks, allocate space for the protected
217    // region at the bottom of the stack.
218    stack_size += Thread::kStackOverflowImplicitCheckSize;
219  }
220
221  // Some systems require the stack size to be a multiple of the system page size, so round up.
222  stack_size = RoundUp(stack_size, kPageSize);
223
224  return stack_size;
225}
226
227// Install a protected region in the stack.  This is used to trigger a SIGSEGV if a stack
228// overflow is detected.  It is located right below the stack_end_.  Just below that
229// is the StackOverflow reserved region used when creating the StackOverflow
230// exception.
231void Thread::InstallImplicitProtection(bool is_main_stack) {
232  byte* pregion = tlsPtr_.stack_end;
233
234  constexpr uint32_t kMarker = 0xdadadada;
235  uintptr_t *marker = reinterpret_cast<uintptr_t*>(pregion);
236  if (*marker == kMarker) {
237    // The region has already been set up.
238    return;
239  }
240  // Add marker so that we can detect a second attempt to do this.
241  *marker = kMarker;
242
243  pregion -= kStackOverflowProtectedSize;
244
245  // Touch the pages in the region to map them in.  Otherwise mprotect fails.  Only
246  // need to do this on the main stack.
247  if (is_main_stack) {
248    memset(pregion, 0x55, kStackOverflowProtectedSize);
249  }
250  VLOG(threads) << "installing stack protected region at " << std::hex <<
251      static_cast<void*>(pregion) << " to " <<
252      static_cast<void*>(pregion + kStackOverflowProtectedSize - 1);
253
254  if (mprotect(pregion, kStackOverflowProtectedSize, PROT_NONE) == -1) {
255    LOG(FATAL) << "Unable to create protected region in stack for implicit overflow check. Reason:"
256        << strerror(errno);
257  }
258}
259
260void Thread::CreateNativeThread(JNIEnv* env, jobject java_peer, size_t stack_size, bool is_daemon) {
261  CHECK(java_peer != nullptr);
262  Thread* self = static_cast<JNIEnvExt*>(env)->self;
263  Runtime* runtime = Runtime::Current();
264
265  // Atomically start the birth of the thread ensuring the runtime isn't shutting down.
266  bool thread_start_during_shutdown = false;
267  {
268    MutexLock mu(self, *Locks::runtime_shutdown_lock_);
269    if (runtime->IsShuttingDownLocked()) {
270      thread_start_during_shutdown = true;
271    } else {
272      runtime->StartThreadBirth();
273    }
274  }
275  if (thread_start_during_shutdown) {
276    ScopedLocalRef<jclass> error_class(env, env->FindClass("java/lang/InternalError"));
277    env->ThrowNew(error_class.get(), "Thread starting during runtime shutdown");
278    return;
279  }
280
281  Thread* child_thread = new Thread(is_daemon);
282  // Use global JNI ref to hold peer live while child thread starts.
283  child_thread->tlsPtr_.jpeer = env->NewGlobalRef(java_peer);
284  stack_size = FixStackSize(stack_size);
285
286  // Thread.start is synchronized, so we know that nativePeer is 0, and know that we're not racing to
287  // assign it.
288  env->SetLongField(java_peer, WellKnownClasses::java_lang_Thread_nativePeer,
289                    reinterpret_cast<jlong>(child_thread));
290
291  pthread_t new_pthread;
292  pthread_attr_t attr;
293  CHECK_PTHREAD_CALL(pthread_attr_init, (&attr), "new thread");
294  CHECK_PTHREAD_CALL(pthread_attr_setdetachstate, (&attr, PTHREAD_CREATE_DETACHED), "PTHREAD_CREATE_DETACHED");
295  CHECK_PTHREAD_CALL(pthread_attr_setstacksize, (&attr, stack_size), stack_size);
296  int pthread_create_result = pthread_create(&new_pthread, &attr, Thread::CreateCallback, child_thread);
297  CHECK_PTHREAD_CALL(pthread_attr_destroy, (&attr), "new thread");
298
299  if (pthread_create_result != 0) {
300    // pthread_create(3) failed, so clean up.
301    {
302      MutexLock mu(self, *Locks::runtime_shutdown_lock_);
303      runtime->EndThreadBirth();
304    }
305    // Manually delete the global reference since Thread::Init will not have been run.
306    env->DeleteGlobalRef(child_thread->tlsPtr_.jpeer);
307    child_thread->tlsPtr_.jpeer = nullptr;
308    delete child_thread;
309    child_thread = nullptr;
310    // TODO: remove from thread group?
311    env->SetLongField(java_peer, WellKnownClasses::java_lang_Thread_nativePeer, 0);
312    {
313      std::string msg(StringPrintf("pthread_create (%s stack) failed: %s",
314                                   PrettySize(stack_size).c_str(), strerror(pthread_create_result)));
315      ScopedObjectAccess soa(env);
316      soa.Self()->ThrowOutOfMemoryError(msg.c_str());
317    }
318  }
319}
320
321void Thread::Init(ThreadList* thread_list, JavaVMExt* java_vm) {
322  // This function does all the initialization that must be run by the native thread it applies to.
323  // (When we create a new thread from managed code, we allocate the Thread* in Thread::Create so
324  // we can handshake with the corresponding native thread when it's ready.) Check this native
325  // thread hasn't been through here already...
326  CHECK(Thread::Current() == nullptr);
327  SetUpAlternateSignalStack();
328  InitCpu();
329  InitTlsEntryPoints();
330  RemoveSuspendTrigger();
331  InitCardTable();
332  InitTid();
333  // Set pthread_self_ ahead of pthread_setspecific, that makes Thread::Current function, this
334  // avoids pthread_self_ ever being invalid when discovered from Thread::Current().
335  tlsPtr_.pthread_self = pthread_self();
336  CHECK(is_started_);
337  CHECK_PTHREAD_CALL(pthread_setspecific, (Thread::pthread_key_self_, this), "attach self");
338  DCHECK_EQ(Thread::Current(), this);
339
340  tls32_.thin_lock_thread_id = thread_list->AllocThreadId(this);
341  InitStackHwm();
342
343  tlsPtr_.jni_env = new JNIEnvExt(this, java_vm);
344  thread_list->Register(this);
345}
346
347Thread* Thread::Attach(const char* thread_name, bool as_daemon, jobject thread_group,
348                       bool create_peer) {
349  Thread* self;
350  Runtime* runtime = Runtime::Current();
351  if (runtime == nullptr) {
352    LOG(ERROR) << "Thread attaching to non-existent runtime: " << thread_name;
353    return nullptr;
354  }
355  {
356    MutexLock mu(nullptr, *Locks::runtime_shutdown_lock_);
357    if (runtime->IsShuttingDownLocked()) {
358      LOG(ERROR) << "Thread attaching while runtime is shutting down: " << thread_name;
359      return nullptr;
360    } else {
361      Runtime::Current()->StartThreadBirth();
362      self = new Thread(as_daemon);
363      self->Init(runtime->GetThreadList(), runtime->GetJavaVM());
364      Runtime::Current()->EndThreadBirth();
365    }
366  }
367
368  CHECK_NE(self->GetState(), kRunnable);
369  self->SetState(kNative);
370
371  // If we're the main thread, ClassLinker won't be created until after we're attached,
372  // so that thread needs a two-stage attach. Regular threads don't need this hack.
373  // In the compiler, all threads need this hack, because no-one's going to be getting
374  // a native peer!
375  if (create_peer) {
376    self->CreatePeer(thread_name, as_daemon, thread_group);
377  } else {
378    // These aren't necessary, but they improve diagnostics for unit tests & command-line tools.
379    if (thread_name != nullptr) {
380      self->tlsPtr_.name->assign(thread_name);
381      ::art::SetThreadName(thread_name);
382    }
383  }
384
385  return self;
386}
387
388void Thread::CreatePeer(const char* name, bool as_daemon, jobject thread_group) {
389  Runtime* runtime = Runtime::Current();
390  CHECK(runtime->IsStarted());
391  JNIEnv* env = tlsPtr_.jni_env;
392
393  if (thread_group == nullptr) {
394    thread_group = runtime->GetMainThreadGroup();
395  }
396  ScopedLocalRef<jobject> thread_name(env, env->NewStringUTF(name));
397  jint thread_priority = GetNativePriority();
398  jboolean thread_is_daemon = as_daemon;
399
400  ScopedLocalRef<jobject> peer(env, env->AllocObject(WellKnownClasses::java_lang_Thread));
401  if (peer.get() == nullptr) {
402    CHECK(IsExceptionPending());
403    return;
404  }
405  {
406    ScopedObjectAccess soa(this);
407    tlsPtr_.opeer = soa.Decode<mirror::Object*>(peer.get());
408  }
409  env->CallNonvirtualVoidMethod(peer.get(),
410                                WellKnownClasses::java_lang_Thread,
411                                WellKnownClasses::java_lang_Thread_init,
412                                thread_group, thread_name.get(), thread_priority, thread_is_daemon);
413  AssertNoPendingException();
414
415  Thread* self = this;
416  DCHECK_EQ(self, Thread::Current());
417  env->SetLongField(peer.get(), WellKnownClasses::java_lang_Thread_nativePeer,
418                    reinterpret_cast<jlong>(self));
419
420  ScopedObjectAccess soa(self);
421  SirtRef<mirror::String> peer_thread_name(soa.Self(), GetThreadName(soa));
422  if (peer_thread_name.get() == nullptr) {
423    // The Thread constructor should have set the Thread.name to a
424    // non-null value. However, because we can run without code
425    // available (in the compiler, in tests), we manually assign the
426    // fields the constructor should have set.
427    if (runtime->IsActiveTransaction()) {
428      InitPeer<true>(soa, thread_is_daemon, thread_group, thread_name.get(), thread_priority);
429    } else {
430      InitPeer<false>(soa, thread_is_daemon, thread_group, thread_name.get(), thread_priority);
431    }
432    peer_thread_name.reset(GetThreadName(soa));
433  }
434  // 'thread_name' may have been null, so don't trust 'peer_thread_name' to be non-null.
435  if (peer_thread_name.get() != nullptr) {
436    SetThreadName(peer_thread_name->ToModifiedUtf8().c_str());
437  }
438}
439
440template<bool kTransactionActive>
441void Thread::InitPeer(ScopedObjectAccess& soa, jboolean thread_is_daemon, jobject thread_group,
442                      jobject thread_name, jint thread_priority) {
443  soa.DecodeField(WellKnownClasses::java_lang_Thread_daemon)->
444      SetBoolean<kTransactionActive>(tlsPtr_.opeer, thread_is_daemon);
445  soa.DecodeField(WellKnownClasses::java_lang_Thread_group)->
446      SetObject<kTransactionActive>(tlsPtr_.opeer, soa.Decode<mirror::Object*>(thread_group));
447  soa.DecodeField(WellKnownClasses::java_lang_Thread_name)->
448      SetObject<kTransactionActive>(tlsPtr_.opeer, soa.Decode<mirror::Object*>(thread_name));
449  soa.DecodeField(WellKnownClasses::java_lang_Thread_priority)->
450      SetInt<kTransactionActive>(tlsPtr_.opeer, thread_priority);
451}
452
453void Thread::SetThreadName(const char* name) {
454  tlsPtr_.name->assign(name);
455  ::art::SetThreadName(name);
456  Dbg::DdmSendThreadNotification(this, CHUNK_TYPE("THNM"));
457}
458
459void Thread::InitStackHwm() {
460  void* read_stack_base;
461  size_t read_stack_size;
462  GetThreadStack(tlsPtr_.pthread_self, &read_stack_base, &read_stack_size);
463
464  // TODO: include this in the thread dumps; potentially useful in SIGQUIT output?
465  VLOG(threads) << StringPrintf("Native stack is at %p (%s)", read_stack_base,
466                                PrettySize(read_stack_size).c_str());
467
468  tlsPtr_.stack_begin = reinterpret_cast<byte*>(read_stack_base);
469  tlsPtr_.stack_size = read_stack_size;
470
471  if (read_stack_size <= kStackOverflowReservedBytes) {
472    LOG(FATAL) << "Attempt to attach a thread with a too-small stack (" << read_stack_size
473        << " bytes)";
474  }
475
476  // TODO: move this into the Linux GetThreadStack implementation.
477#if !defined(__APPLE__)
478  // If we're the main thread, check whether we were run with an unlimited stack. In that case,
479  // glibc will have reported a 2GB stack for our 32-bit process, and our stack overflow detection
480  // will be broken because we'll die long before we get close to 2GB.
481  bool is_main_thread = (::art::GetTid() == getpid());
482  if (is_main_thread) {
483    rlimit stack_limit;
484    if (getrlimit(RLIMIT_STACK, &stack_limit) == -1) {
485      PLOG(FATAL) << "getrlimit(RLIMIT_STACK) failed";
486    }
487    if (stack_limit.rlim_cur == RLIM_INFINITY) {
488      // Find the default stack size for new threads...
489      pthread_attr_t default_attributes;
490      size_t default_stack_size;
491      CHECK_PTHREAD_CALL(pthread_attr_init, (&default_attributes), "default stack size query");
492      CHECK_PTHREAD_CALL(pthread_attr_getstacksize, (&default_attributes, &default_stack_size),
493                         "default stack size query");
494      CHECK_PTHREAD_CALL(pthread_attr_destroy, (&default_attributes), "default stack size query");
495
496      // ...and use that as our limit.
497      size_t old_stack_size = read_stack_size;
498      tlsPtr_.stack_size = default_stack_size;
499      tlsPtr_.stack_begin += (old_stack_size - default_stack_size);
500      VLOG(threads) << "Limiting unlimited stack (reported as " << PrettySize(old_stack_size) << ")"
501                    << " to " << PrettySize(default_stack_size)
502                    << " with base " << reinterpret_cast<void*>(tlsPtr_.stack_begin);
503    }
504  }
505#endif
506
507  // Set stack_end_ to the bottom of the stack saving space of stack overflows
508  bool implicit_stack_check = !Runtime::Current()->ExplicitStackOverflowChecks();
509  ResetDefaultStackEnd(implicit_stack_check);
510
511  // Install the protected region if we are doing implicit overflow checks.
512  if (implicit_stack_check) {
513    if (is_main_thread) {
514      // The main thread has a 16K protected region at the bottom.  We need
515      // to install our own region so we need to move the limits
516      // of the stack to make room for it.
517      constexpr uint32_t kDelta = 16 * KB;
518      tlsPtr_.stack_begin += kDelta;
519      tlsPtr_.stack_end += kDelta;
520      tlsPtr_.stack_size -= kDelta;
521    }
522    InstallImplicitProtection(is_main_thread);
523  }
524
525  // Sanity check.
526  int stack_variable;
527  CHECK_GT(&stack_variable, reinterpret_cast<void*>(tlsPtr_.stack_end));
528}
529
530void Thread::ShortDump(std::ostream& os) const {
531  os << "Thread[";
532  if (GetThreadId() != 0) {
533    // If we're in kStarting, we won't have a thin lock id or tid yet.
534    os << GetThreadId()
535             << ",tid=" << GetTid() << ',';
536  }
537  os << GetState()
538           << ",Thread*=" << this
539           << ",peer=" << tlsPtr_.opeer
540           << ",\"" << *tlsPtr_.name << "\""
541           << "]";
542}
543
544void Thread::Dump(std::ostream& os) const {
545  DumpState(os);
546  DumpStack(os);
547}
548
549mirror::String* Thread::GetThreadName(const ScopedObjectAccessUnchecked& soa) const {
550  mirror::ArtField* f = soa.DecodeField(WellKnownClasses::java_lang_Thread_name);
551  return (tlsPtr_.opeer != nullptr) ? reinterpret_cast<mirror::String*>(f->GetObject(tlsPtr_.opeer)) : nullptr;
552}
553
554void Thread::GetThreadName(std::string& name) const {
555  name.assign(*tlsPtr_.name);
556}
557
558uint64_t Thread::GetCpuMicroTime() const {
559#if defined(HAVE_POSIX_CLOCKS)
560  clockid_t cpu_clock_id;
561  pthread_getcpuclockid(tlsPtr_.pthread_self, &cpu_clock_id);
562  timespec now;
563  clock_gettime(cpu_clock_id, &now);
564  return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000) + now.tv_nsec / UINT64_C(1000);
565#else
566  UNIMPLEMENTED(WARNING);
567  return -1;
568#endif
569}
570
571void Thread::AtomicSetFlag(ThreadFlag flag) {
572  android_atomic_or(flag, &tls32_.state_and_flags.as_int);
573}
574
575void Thread::AtomicClearFlag(ThreadFlag flag) {
576  android_atomic_and(-1 ^ flag, &tls32_.state_and_flags.as_int);
577}
578
579// Attempt to rectify locks so that we dump thread list with required locks before exiting.
580static void UnsafeLogFatalForSuspendCount(Thread* self, Thread* thread) NO_THREAD_SAFETY_ANALYSIS {
581  LOG(ERROR) << *thread << " suspend count already zero.";
582  Locks::thread_suspend_count_lock_->Unlock(self);
583  if (!Locks::mutator_lock_->IsSharedHeld(self)) {
584    Locks::mutator_lock_->SharedTryLock(self);
585    if (!Locks::mutator_lock_->IsSharedHeld(self)) {
586      LOG(WARNING) << "Dumping thread list without holding mutator_lock_";
587    }
588  }
589  if (!Locks::thread_list_lock_->IsExclusiveHeld(self)) {
590    Locks::thread_list_lock_->TryLock(self);
591    if (!Locks::thread_list_lock_->IsExclusiveHeld(self)) {
592      LOG(WARNING) << "Dumping thread list without holding thread_list_lock_";
593    }
594  }
595  std::ostringstream ss;
596  Runtime::Current()->GetThreadList()->DumpLocked(ss);
597  LOG(FATAL) << ss.str();
598}
599
600void Thread::ModifySuspendCount(Thread* self, int delta, bool for_debugger) {
601  if (kIsDebugBuild) {
602    DCHECK(delta == -1 || delta == +1 || delta == -tls32_.debug_suspend_count)
603          << delta << " " << tls32_.debug_suspend_count << " " << this;
604    DCHECK_GE(tls32_.suspend_count, tls32_.debug_suspend_count) << this;
605    Locks::thread_suspend_count_lock_->AssertHeld(self);
606    if (this != self && !IsSuspended()) {
607      Locks::thread_list_lock_->AssertHeld(self);
608    }
609  }
610  if (UNLIKELY(delta < 0 && tls32_.suspend_count <= 0)) {
611    UnsafeLogFatalForSuspendCount(self, this);
612    return;
613  }
614
615  tls32_.suspend_count += delta;
616  if (for_debugger) {
617    tls32_.debug_suspend_count += delta;
618  }
619
620  if (tls32_.suspend_count == 0) {
621    AtomicClearFlag(kSuspendRequest);
622  } else {
623    AtomicSetFlag(kSuspendRequest);
624    TriggerSuspend();
625  }
626}
627
628void Thread::RunCheckpointFunction() {
629  Closure *checkpoints[kMaxCheckpoints];
630
631  // Grab the suspend_count lock and copy the current set of
632  // checkpoints.  Then clear the list and the flag.  The RequestCheckpoint
633  // function will also grab this lock so we prevent a race between setting
634  // the kCheckpointRequest flag and clearing it.
635  {
636    MutexLock mu(this, *Locks::thread_suspend_count_lock_);
637    for (uint32_t i = 0; i < kMaxCheckpoints; ++i) {
638      checkpoints[i] = tlsPtr_.checkpoint_functions[i];
639      tlsPtr_.checkpoint_functions[i] = nullptr;
640    }
641    AtomicClearFlag(kCheckpointRequest);
642  }
643
644  // Outside the lock, run all the checkpoint functions that
645  // we collected.
646  bool found_checkpoint = false;
647  for (uint32_t i = 0; i < kMaxCheckpoints; ++i) {
648    if (checkpoints[i] != nullptr) {
649      ATRACE_BEGIN("Checkpoint function");
650      checkpoints[i]->Run(this);
651      ATRACE_END();
652      found_checkpoint = true;
653    }
654  }
655  CHECK(found_checkpoint);
656}
657
658bool Thread::RequestCheckpoint(Closure* function) {
659  union StateAndFlags old_state_and_flags;
660  old_state_and_flags.as_int = tls32_.state_and_flags.as_int;
661  if (old_state_and_flags.as_struct.state != kRunnable) {
662    return false;  // Fail, thread is suspended and so can't run a checkpoint.
663  }
664
665  uint32_t available_checkpoint = kMaxCheckpoints;
666  for (uint32_t i = 0 ; i < kMaxCheckpoints; ++i) {
667    if (tlsPtr_.checkpoint_functions[i] == nullptr) {
668      available_checkpoint = i;
669      break;
670    }
671  }
672  if (available_checkpoint == kMaxCheckpoints) {
673    // No checkpoint functions available, we can't run a checkpoint
674    return false;
675  }
676  tlsPtr_.checkpoint_functions[available_checkpoint] = function;
677
678  // Checkpoint function installed now install flag bit.
679  // We must be runnable to request a checkpoint.
680  DCHECK_EQ(old_state_and_flags.as_struct.state, kRunnable);
681  union StateAndFlags new_state_and_flags;
682  new_state_and_flags.as_int = old_state_and_flags.as_int;
683  new_state_and_flags.as_struct.flags |= kCheckpointRequest;
684  int succeeded = android_atomic_acquire_cas(old_state_and_flags.as_int, new_state_and_flags.as_int,
685                                             &tls32_.state_and_flags.as_int);
686  if (UNLIKELY(succeeded != 0)) {
687    // The thread changed state before the checkpoint was installed.
688    CHECK_EQ(tlsPtr_.checkpoint_functions[available_checkpoint], function);
689    tlsPtr_.checkpoint_functions[available_checkpoint] = nullptr;
690  } else {
691    CHECK_EQ(ReadFlag(kCheckpointRequest), true);
692    TriggerSuspend();
693  }
694  return succeeded == 0;
695}
696
697void Thread::FullSuspendCheck() {
698  VLOG(threads) << this << " self-suspending";
699  ATRACE_BEGIN("Full suspend check");
700  // Make thread appear suspended to other threads, release mutator_lock_.
701  TransitionFromRunnableToSuspended(kSuspended);
702  // Transition back to runnable noting requests to suspend, re-acquire share on mutator_lock_.
703  TransitionFromSuspendedToRunnable();
704  ATRACE_END();
705  VLOG(threads) << this << " self-reviving";
706}
707
708void Thread::DumpState(std::ostream& os, const Thread* thread, pid_t tid) {
709  std::string group_name;
710  int priority;
711  bool is_daemon = false;
712  Thread* self = Thread::Current();
713
714  // Don't do this if we are aborting since the GC may have all the threads suspended. This will
715  // cause ScopedObjectAccessUnchecked to deadlock.
716  if (gAborting == 0 && self != nullptr && thread != nullptr && thread->tlsPtr_.opeer != nullptr) {
717    ScopedObjectAccessUnchecked soa(self);
718    priority = soa.DecodeField(WellKnownClasses::java_lang_Thread_priority)
719        ->GetInt(thread->tlsPtr_.opeer);
720    is_daemon = soa.DecodeField(WellKnownClasses::java_lang_Thread_daemon)
721        ->GetBoolean(thread->tlsPtr_.opeer);
722
723    mirror::Object* thread_group =
724        soa.DecodeField(WellKnownClasses::java_lang_Thread_group)->GetObject(thread->tlsPtr_.opeer);
725
726    if (thread_group != nullptr) {
727      mirror::ArtField* group_name_field =
728          soa.DecodeField(WellKnownClasses::java_lang_ThreadGroup_name);
729      mirror::String* group_name_string =
730          reinterpret_cast<mirror::String*>(group_name_field->GetObject(thread_group));
731      group_name = (group_name_string != nullptr) ? group_name_string->ToModifiedUtf8() : "<null>";
732    }
733  } else {
734    priority = GetNativePriority();
735  }
736
737  std::string scheduler_group_name(GetSchedulerGroupName(tid));
738  if (scheduler_group_name.empty()) {
739    scheduler_group_name = "default";
740  }
741
742  if (thread != nullptr) {
743    os << '"' << *thread->tlsPtr_.name << '"';
744    if (is_daemon) {
745      os << " daemon";
746    }
747    os << " prio=" << priority
748       << " tid=" << thread->GetThreadId()
749       << " " << thread->GetState();
750    if (thread->IsStillStarting()) {
751      os << " (still starting up)";
752    }
753    os << "\n";
754  } else {
755    os << '"' << ::art::GetThreadName(tid) << '"'
756       << " prio=" << priority
757       << " (not attached)\n";
758  }
759
760  if (thread != nullptr) {
761    MutexLock mu(self, *Locks::thread_suspend_count_lock_);
762    os << "  | group=\"" << group_name << "\""
763       << " sCount=" << thread->tls32_.suspend_count
764       << " dsCount=" << thread->tls32_.debug_suspend_count
765       << " obj=" << reinterpret_cast<void*>(thread->tlsPtr_.opeer)
766       << " self=" << reinterpret_cast<const void*>(thread) << "\n";
767  }
768
769  os << "  | sysTid=" << tid
770     << " nice=" << getpriority(PRIO_PROCESS, tid)
771     << " cgrp=" << scheduler_group_name;
772  if (thread != nullptr) {
773    int policy;
774    sched_param sp;
775    CHECK_PTHREAD_CALL(pthread_getschedparam, (thread->tlsPtr_.pthread_self, &policy, &sp),
776                       __FUNCTION__);
777    os << " sched=" << policy << "/" << sp.sched_priority
778       << " handle=" << reinterpret_cast<void*>(thread->tlsPtr_.pthread_self);
779  }
780  os << "\n";
781
782  // Grab the scheduler stats for this thread.
783  std::string scheduler_stats;
784  if (ReadFileToString(StringPrintf("/proc/self/task/%d/schedstat", tid), &scheduler_stats)) {
785    scheduler_stats.resize(scheduler_stats.size() - 1);  // Lose the trailing '\n'.
786  } else {
787    scheduler_stats = "0 0 0";
788  }
789
790  char native_thread_state = '?';
791  int utime = 0;
792  int stime = 0;
793  int task_cpu = 0;
794  GetTaskStats(tid, &native_thread_state, &utime, &stime, &task_cpu);
795
796  os << "  | state=" << native_thread_state
797     << " schedstat=( " << scheduler_stats << " )"
798     << " utm=" << utime
799     << " stm=" << stime
800     << " core=" << task_cpu
801     << " HZ=" << sysconf(_SC_CLK_TCK) << "\n";
802  if (thread != nullptr) {
803    os << "  | stack=" << reinterpret_cast<void*>(thread->tlsPtr_.stack_begin) << "-"
804        << reinterpret_cast<void*>(thread->tlsPtr_.stack_end) << " stackSize="
805        << PrettySize(thread->tlsPtr_.stack_size) << "\n";
806  }
807}
808
809void Thread::DumpState(std::ostream& os) const {
810  Thread::DumpState(os, this, GetTid());
811}
812
813struct StackDumpVisitor : public StackVisitor {
814  StackDumpVisitor(std::ostream& os, Thread* thread, Context* context, bool can_allocate)
815      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
816      : StackVisitor(thread, context), os(os), thread(thread), can_allocate(can_allocate),
817        last_method(nullptr), last_line_number(0), repetition_count(0), frame_count(0) {
818  }
819
820  virtual ~StackDumpVisitor() {
821    if (frame_count == 0) {
822      os << "  (no managed stack frames)\n";
823    }
824  }
825
826  bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
827    mirror::ArtMethod* m = GetMethod();
828    if (m->IsRuntimeMethod()) {
829      return true;
830    }
831    const int kMaxRepetition = 3;
832    mirror::Class* c = m->GetDeclaringClass();
833    mirror::DexCache* dex_cache = c->GetDexCache();
834    int line_number = -1;
835    if (dex_cache != nullptr) {  // be tolerant of bad input
836      const DexFile& dex_file = *dex_cache->GetDexFile();
837      line_number = dex_file.GetLineNumFromPC(m, GetDexPc(false));
838    }
839    if (line_number == last_line_number && last_method == m) {
840      ++repetition_count;
841    } else {
842      if (repetition_count >= kMaxRepetition) {
843        os << "  ... repeated " << (repetition_count - kMaxRepetition) << " times\n";
844      }
845      repetition_count = 0;
846      last_line_number = line_number;
847      last_method = m;
848    }
849    if (repetition_count < kMaxRepetition) {
850      os << "  at " << PrettyMethod(m, false);
851      if (m->IsNative()) {
852        os << "(Native method)";
853      } else {
854        mh.ChangeMethod(m);
855        const char* source_file(mh.GetDeclaringClassSourceFile());
856        os << "(" << (source_file != nullptr ? source_file : "unavailable")
857           << ":" << line_number << ")";
858      }
859      os << "\n";
860      if (frame_count == 0) {
861        Monitor::DescribeWait(os, thread);
862      }
863      if (can_allocate) {
864        Monitor::VisitLocks(this, DumpLockedObject, &os);
865      }
866    }
867
868    ++frame_count;
869    return true;
870  }
871
872  static void DumpLockedObject(mirror::Object* o, void* context)
873      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
874    std::ostream& os = *reinterpret_cast<std::ostream*>(context);
875    os << "  - locked ";
876    if (o == nullptr) {
877      os << "an unknown object";
878    } else {
879      if ((o->GetLockWord(false).GetState() == LockWord::kThinLocked) &&
880          Locks::mutator_lock_->IsExclusiveHeld(Thread::Current())) {
881        // Getting the identity hashcode here would result in lock inflation and suspension of the
882        // current thread, which isn't safe if this is the only runnable thread.
883        os << StringPrintf("<@addr=0x%" PRIxPTR "> (a %s)", reinterpret_cast<intptr_t>(o),
884                           PrettyTypeOf(o).c_str());
885      } else {
886        os << StringPrintf("<0x%08x> (a %s)", o->IdentityHashCode(), PrettyTypeOf(o).c_str());
887      }
888    }
889    os << "\n";
890  }
891
892  std::ostream& os;
893  const Thread* thread;
894  const bool can_allocate;
895  MethodHelper mh;
896  mirror::ArtMethod* last_method;
897  int last_line_number;
898  int repetition_count;
899  int frame_count;
900};
901
902static bool ShouldShowNativeStack(const Thread* thread)
903    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
904  ThreadState state = thread->GetState();
905
906  // In native code somewhere in the VM (one of the kWaitingFor* states)? That's interesting.
907  if (state > kWaiting && state < kStarting) {
908    return true;
909  }
910
911  // In an Object.wait variant or Thread.sleep? That's not interesting.
912  if (state == kTimedWaiting || state == kSleeping || state == kWaiting) {
913    return false;
914  }
915
916  // In some other native method? That's interesting.
917  // We don't just check kNative because native methods will be in state kSuspended if they're
918  // calling back into the VM, or kBlocked if they're blocked on a monitor, or one of the
919  // thread-startup states if it's early enough in their life cycle (http://b/7432159).
920  mirror::ArtMethod* current_method = thread->GetCurrentMethod(nullptr);
921  return current_method != nullptr && current_method->IsNative();
922}
923
924void Thread::DumpJavaStack(std::ostream& os) const {
925  UniquePtr<Context> context(Context::Create());
926  StackDumpVisitor dumper(os, const_cast<Thread*>(this), context.get(),
927                          !tls32_.throwing_OutOfMemoryError);
928  dumper.WalkStack();
929}
930
931void Thread::DumpStack(std::ostream& os) const {
932  // TODO: we call this code when dying but may not have suspended the thread ourself. The
933  //       IsSuspended check is therefore racy with the use for dumping (normally we inhibit
934  //       the race with the thread_suspend_count_lock_).
935  // No point dumping for an abort in debug builds where we'll hit the not suspended check in stack.
936  bool dump_for_abort = (gAborting > 0) && !kIsDebugBuild;
937  if (this == Thread::Current() || IsSuspended() || dump_for_abort) {
938    // If we're currently in native code, dump that stack before dumping the managed stack.
939    if (dump_for_abort || ShouldShowNativeStack(this)) {
940      DumpKernelStack(os, GetTid(), "  kernel: ", false);
941      SirtRef<mirror::ArtMethod> method_ref(Thread::Current(), GetCurrentMethod(nullptr));
942      DumpNativeStack(os, GetTid(), "  native: ", method_ref.get());
943    }
944    DumpJavaStack(os);
945  } else {
946    os << "Not able to dump stack of thread that isn't suspended";
947  }
948}
949
950void Thread::ThreadExitCallback(void* arg) {
951  Thread* self = reinterpret_cast<Thread*>(arg);
952  if (self->tls32_.thread_exit_check_count == 0) {
953    LOG(WARNING) << "Native thread exiting without having called DetachCurrentThread (maybe it's "
954        "going to use a pthread_key_create destructor?): " << *self;
955    CHECK(is_started_);
956    CHECK_PTHREAD_CALL(pthread_setspecific, (Thread::pthread_key_self_, self), "reattach self");
957    self->tls32_.thread_exit_check_count = 1;
958  } else {
959    LOG(FATAL) << "Native thread exited without calling DetachCurrentThread: " << *self;
960  }
961}
962
963void Thread::Startup() {
964  CHECK(!is_started_);
965  is_started_ = true;
966  {
967    // MutexLock to keep annotalysis happy.
968    //
969    // Note we use nullptr for the thread because Thread::Current can
970    // return garbage since (is_started_ == true) and
971    // Thread::pthread_key_self_ is not yet initialized.
972    // This was seen on glibc.
973    MutexLock mu(nullptr, *Locks::thread_suspend_count_lock_);
974    resume_cond_ = new ConditionVariable("Thread resumption condition variable",
975                                         *Locks::thread_suspend_count_lock_);
976  }
977
978  // Allocate a TLS slot.
979  CHECK_PTHREAD_CALL(pthread_key_create, (&Thread::pthread_key_self_, Thread::ThreadExitCallback), "self key");
980
981  // Double-check the TLS slot allocation.
982  if (pthread_getspecific(pthread_key_self_) != nullptr) {
983    LOG(FATAL) << "Newly-created pthread TLS slot is not nullptr";
984  }
985}
986
987void Thread::FinishStartup() {
988  Runtime* runtime = Runtime::Current();
989  CHECK(runtime->IsStarted());
990
991  // Finish attaching the main thread.
992  ScopedObjectAccess soa(Thread::Current());
993  Thread::Current()->CreatePeer("main", false, runtime->GetMainThreadGroup());
994
995  Runtime::Current()->GetClassLinker()->RunRootClinits();
996}
997
998void Thread::Shutdown() {
999  CHECK(is_started_);
1000  is_started_ = false;
1001  CHECK_PTHREAD_CALL(pthread_key_delete, (Thread::pthread_key_self_), "self key");
1002  MutexLock mu(Thread::Current(), *Locks::thread_suspend_count_lock_);
1003  if (resume_cond_ != nullptr) {
1004    delete resume_cond_;
1005    resume_cond_ = nullptr;
1006  }
1007}
1008
1009Thread::Thread(bool daemon) : tls32_(daemon), wait_monitor_(nullptr), interrupted_(false) {
1010  wait_mutex_ = new Mutex("a thread wait mutex");
1011  wait_cond_ = new ConditionVariable("a thread wait condition variable", *wait_mutex_);
1012  tlsPtr_.debug_invoke_req = new DebugInvokeReq;
1013  tlsPtr_.single_step_control = new SingleStepControl;
1014  tlsPtr_.instrumentation_stack = new std::deque<instrumentation::InstrumentationStackFrame>;
1015  tlsPtr_.name = new std::string(kThreadNameDuringStartup);
1016
1017  CHECK_EQ((sizeof(Thread) % 4), 0U) << sizeof(Thread);
1018  tls32_.state_and_flags.as_struct.flags = 0;
1019  tls32_.state_and_flags.as_struct.state = kNative;
1020  memset(&tlsPtr_.held_mutexes[0], 0, sizeof(tlsPtr_.held_mutexes));
1021  std::fill(tlsPtr_.rosalloc_runs, tlsPtr_.rosalloc_runs + kRosAllocNumOfSizeBrackets,
1022            gc::allocator::RosAlloc::GetDedicatedFullRun());
1023  for (uint32_t i = 0; i < kMaxCheckpoints; ++i) {
1024    tlsPtr_.checkpoint_functions[i] = nullptr;
1025  }
1026}
1027
1028bool Thread::IsStillStarting() const {
1029  // You might think you can check whether the state is kStarting, but for much of thread startup,
1030  // the thread is in kNative; it might also be in kVmWait.
1031  // You might think you can check whether the peer is nullptr, but the peer is actually created and
1032  // assigned fairly early on, and needs to be.
1033  // It turns out that the last thing to change is the thread name; that's a good proxy for "has
1034  // this thread _ever_ entered kRunnable".
1035  return (tlsPtr_.jpeer == nullptr && tlsPtr_.opeer == nullptr) ||
1036      (*tlsPtr_.name == kThreadNameDuringStartup);
1037}
1038
1039void Thread::AssertNoPendingException() const {
1040  if (UNLIKELY(IsExceptionPending())) {
1041    ScopedObjectAccess soa(Thread::Current());
1042    mirror::Throwable* exception = GetException(nullptr);
1043    LOG(FATAL) << "No pending exception expected: " << exception->Dump();
1044  }
1045}
1046
1047void Thread::AssertNoPendingExceptionForNewException(const char* msg) const {
1048  if (UNLIKELY(IsExceptionPending())) {
1049    ScopedObjectAccess soa(Thread::Current());
1050    mirror::Throwable* exception = GetException(nullptr);
1051    LOG(FATAL) << "Throwing new exception " << msg << " with unexpected pending exception: "
1052        << exception->Dump();
1053  }
1054}
1055
1056static void MonitorExitVisitor(mirror::Object** object, void* arg, uint32_t /*thread_id*/,
1057                               RootType /*root_type*/)
1058    NO_THREAD_SAFETY_ANALYSIS {
1059  Thread* self = reinterpret_cast<Thread*>(arg);
1060  mirror::Object* entered_monitor = *object;
1061  if (self->HoldsLock(entered_monitor)) {
1062    LOG(WARNING) << "Calling MonitorExit on object "
1063                 << object << " (" << PrettyTypeOf(entered_monitor) << ")"
1064                 << " left locked by native thread "
1065                 << *Thread::Current() << " which is detaching";
1066    entered_monitor->MonitorExit(self);
1067  }
1068}
1069
1070void Thread::Destroy() {
1071  Thread* self = this;
1072  DCHECK_EQ(self, Thread::Current());
1073
1074  if (tlsPtr_.opeer != nullptr) {
1075    ScopedObjectAccess soa(self);
1076    // We may need to call user-supplied managed code, do this before final clean-up.
1077    HandleUncaughtExceptions(soa);
1078    RemoveFromThreadGroup(soa);
1079
1080    // this.nativePeer = 0;
1081    if (Runtime::Current()->IsActiveTransaction()) {
1082      soa.DecodeField(WellKnownClasses::java_lang_Thread_nativePeer)
1083          ->SetLong<true>(tlsPtr_.opeer, 0);
1084    } else {
1085      soa.DecodeField(WellKnownClasses::java_lang_Thread_nativePeer)
1086          ->SetLong<false>(tlsPtr_.opeer, 0);
1087    }
1088    Dbg::PostThreadDeath(self);
1089
1090    // Thread.join() is implemented as an Object.wait() on the Thread.lock object. Signal anyone
1091    // who is waiting.
1092    mirror::Object* lock =
1093        soa.DecodeField(WellKnownClasses::java_lang_Thread_lock)->GetObject(tlsPtr_.opeer);
1094    // (This conditional is only needed for tests, where Thread.lock won't have been set.)
1095    if (lock != nullptr) {
1096      SirtRef<mirror::Object> sirt_obj(self, lock);
1097      ObjectLock<mirror::Object> locker(self, &sirt_obj);
1098      locker.NotifyAll();
1099    }
1100  }
1101
1102  // On thread detach, all monitors entered with JNI MonitorEnter are automatically exited.
1103  if (tlsPtr_.jni_env != nullptr) {
1104    tlsPtr_.jni_env->monitors.VisitRoots(MonitorExitVisitor, self, 0, kRootVMInternal);
1105  }
1106}
1107
1108Thread::~Thread() {
1109  if (tlsPtr_.jni_env != nullptr && tlsPtr_.jpeer != nullptr) {
1110    // If pthread_create fails we don't have a jni env here.
1111    tlsPtr_.jni_env->DeleteGlobalRef(tlsPtr_.jpeer);
1112    tlsPtr_.jpeer = nullptr;
1113  }
1114  tlsPtr_.opeer = nullptr;
1115
1116  bool initialized = (tlsPtr_.jni_env != nullptr);  // Did Thread::Init run?
1117  if (initialized) {
1118    delete tlsPtr_.jni_env;
1119    tlsPtr_.jni_env = nullptr;
1120  }
1121  CHECK_NE(GetState(), kRunnable);
1122  CHECK_NE(ReadFlag(kCheckpointRequest), true);
1123  CHECK(tlsPtr_.checkpoint_functions[0] == nullptr);
1124  CHECK(tlsPtr_.checkpoint_functions[1] == nullptr);
1125  CHECK(tlsPtr_.checkpoint_functions[2] == nullptr);
1126
1127  // We may be deleting a still born thread.
1128  SetStateUnsafe(kTerminated);
1129
1130  delete wait_cond_;
1131  delete wait_mutex_;
1132
1133  if (tlsPtr_.long_jump_context != nullptr) {
1134    delete tlsPtr_.long_jump_context;
1135  }
1136
1137  if (initialized) {
1138    CleanupCpu();
1139  }
1140
1141  delete tlsPtr_.debug_invoke_req;
1142  delete tlsPtr_.single_step_control;
1143  delete tlsPtr_.instrumentation_stack;
1144  delete tlsPtr_.name;
1145  delete tlsPtr_.stack_trace_sample;
1146
1147  Runtime::Current()->GetHeap()->RevokeThreadLocalBuffers(this);
1148
1149  TearDownAlternateSignalStack();
1150}
1151
1152void Thread::HandleUncaughtExceptions(ScopedObjectAccess& soa) {
1153  if (!IsExceptionPending()) {
1154    return;
1155  }
1156  ScopedLocalRef<jobject> peer(tlsPtr_.jni_env, soa.AddLocalReference<jobject>(tlsPtr_.opeer));
1157  ScopedThreadStateChange tsc(this, kNative);
1158
1159  // Get and clear the exception.
1160  ScopedLocalRef<jthrowable> exception(tlsPtr_.jni_env, tlsPtr_.jni_env->ExceptionOccurred());
1161  tlsPtr_.jni_env->ExceptionClear();
1162
1163  // If the thread has its own handler, use that.
1164  ScopedLocalRef<jobject> handler(tlsPtr_.jni_env,
1165                                  tlsPtr_.jni_env->GetObjectField(peer.get(),
1166                                      WellKnownClasses::java_lang_Thread_uncaughtHandler));
1167  if (handler.get() == nullptr) {
1168    // Otherwise use the thread group's default handler.
1169    handler.reset(tlsPtr_.jni_env->GetObjectField(peer.get(),
1170                                                  WellKnownClasses::java_lang_Thread_group));
1171  }
1172
1173  // Call the handler.
1174  tlsPtr_.jni_env->CallVoidMethod(handler.get(),
1175      WellKnownClasses::java_lang_Thread$UncaughtExceptionHandler_uncaughtException,
1176      peer.get(), exception.get());
1177
1178  // If the handler threw, clear that exception too.
1179  tlsPtr_.jni_env->ExceptionClear();
1180}
1181
1182void Thread::RemoveFromThreadGroup(ScopedObjectAccess& soa) {
1183  // this.group.removeThread(this);
1184  // group can be null if we're in the compiler or a test.
1185  mirror::Object* ogroup = soa.DecodeField(WellKnownClasses::java_lang_Thread_group)
1186      ->GetObject(tlsPtr_.opeer);
1187  if (ogroup != nullptr) {
1188    ScopedLocalRef<jobject> group(soa.Env(), soa.AddLocalReference<jobject>(ogroup));
1189    ScopedLocalRef<jobject> peer(soa.Env(), soa.AddLocalReference<jobject>(tlsPtr_.opeer));
1190    ScopedThreadStateChange tsc(soa.Self(), kNative);
1191    tlsPtr_.jni_env->CallVoidMethod(group.get(),
1192                                    WellKnownClasses::java_lang_ThreadGroup_removeThread,
1193                                    peer.get());
1194  }
1195}
1196
1197size_t Thread::NumSirtReferences() {
1198  size_t count = 0;
1199  for (StackIndirectReferenceTable* cur = tlsPtr_.top_sirt; cur; cur = cur->GetLink()) {
1200    count += cur->NumberOfReferences();
1201  }
1202  return count;
1203}
1204
1205bool Thread::SirtContains(jobject obj) const {
1206  StackReference<mirror::Object>* sirt_entry =
1207      reinterpret_cast<StackReference<mirror::Object>*>(obj);
1208  for (StackIndirectReferenceTable* cur = tlsPtr_.top_sirt; cur; cur = cur->GetLink()) {
1209    if (cur->Contains(sirt_entry)) {
1210      return true;
1211    }
1212  }
1213  // JNI code invoked from portable code uses shadow frames rather than the SIRT.
1214  return tlsPtr_.managed_stack.ShadowFramesContain(sirt_entry);
1215}
1216
1217void Thread::SirtVisitRoots(RootCallback* visitor, void* arg, uint32_t thread_id) {
1218  for (StackIndirectReferenceTable* cur = tlsPtr_.top_sirt; cur; cur = cur->GetLink()) {
1219    size_t num_refs = cur->NumberOfReferences();
1220    for (size_t j = 0; j < num_refs; ++j) {
1221      mirror::Object* object = cur->GetReference(j);
1222      if (object != nullptr) {
1223        mirror::Object* old_obj = object;
1224        visitor(&object, arg, thread_id, kRootNativeStack);
1225        if (old_obj != object) {
1226          cur->SetReference(j, object);
1227        }
1228      }
1229    }
1230  }
1231}
1232
1233mirror::Object* Thread::DecodeJObject(jobject obj) const {
1234  Locks::mutator_lock_->AssertSharedHeld(this);
1235  if (obj == nullptr) {
1236    return nullptr;
1237  }
1238  IndirectRef ref = reinterpret_cast<IndirectRef>(obj);
1239  IndirectRefKind kind = GetIndirectRefKind(ref);
1240  mirror::Object* result;
1241  // The "kinds" below are sorted by the frequency we expect to encounter them.
1242  if (kind == kLocal) {
1243    IndirectReferenceTable& locals = tlsPtr_.jni_env->locals;
1244    result = locals.Get(ref);
1245  } else if (kind == kSirtOrInvalid) {
1246    // TODO: make stack indirect reference table lookup more efficient.
1247    // Check if this is a local reference in the SIRT.
1248    if (LIKELY(SirtContains(obj))) {
1249      // Read from SIRT.
1250      result = reinterpret_cast<StackReference<mirror::Object>*>(obj)->AsMirrorPtr();
1251      VerifyObject(result);
1252    } else {
1253      result = kInvalidIndirectRefObject;
1254    }
1255  } else if (kind == kGlobal) {
1256    JavaVMExt* vm = Runtime::Current()->GetJavaVM();
1257    IndirectReferenceTable& globals = vm->globals;
1258    ReaderMutexLock mu(const_cast<Thread*>(this), vm->globals_lock);
1259    result = const_cast<mirror::Object*>(globals.Get(ref));
1260  } else {
1261    DCHECK_EQ(kind, kWeakGlobal);
1262    result = Runtime::Current()->GetJavaVM()->DecodeWeakGlobal(const_cast<Thread*>(this), ref);
1263    if (result == kClearedJniWeakGlobal) {
1264      // This is a special case where it's okay to return nullptr.
1265      return nullptr;
1266    }
1267  }
1268
1269  if (UNLIKELY(result == nullptr)) {
1270    JniAbortF(nullptr, "use of deleted %s %p", ToStr<IndirectRefKind>(kind).c_str(), obj);
1271  }
1272  return result;
1273}
1274
1275// Implements java.lang.Thread.interrupted.
1276bool Thread::Interrupted() {
1277  MutexLock mu(Thread::Current(), *wait_mutex_);
1278  bool interrupted = IsInterruptedLocked();
1279  SetInterruptedLocked(false);
1280  return interrupted;
1281}
1282
1283// Implements java.lang.Thread.isInterrupted.
1284bool Thread::IsInterrupted() {
1285  MutexLock mu(Thread::Current(), *wait_mutex_);
1286  return IsInterruptedLocked();
1287}
1288
1289void Thread::Interrupt(Thread* self) {
1290  MutexLock mu(self, *wait_mutex_);
1291  if (interrupted_) {
1292    return;
1293  }
1294  interrupted_ = true;
1295  NotifyLocked(self);
1296}
1297
1298void Thread::Notify() {
1299  Thread* self = Thread::Current();
1300  MutexLock mu(self, *wait_mutex_);
1301  NotifyLocked(self);
1302}
1303
1304void Thread::NotifyLocked(Thread* self) {
1305  if (wait_monitor_ != nullptr) {
1306    wait_cond_->Signal(self);
1307  }
1308}
1309
1310class CountStackDepthVisitor : public StackVisitor {
1311 public:
1312  explicit CountStackDepthVisitor(Thread* thread)
1313      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
1314      : StackVisitor(thread, nullptr),
1315        depth_(0), skip_depth_(0), skipping_(true) {}
1316
1317  bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1318    // We want to skip frames up to and including the exception's constructor.
1319    // Note we also skip the frame if it doesn't have a method (namely the callee
1320    // save frame)
1321    mirror::ArtMethod* m = GetMethod();
1322    if (skipping_ && !m->IsRuntimeMethod() &&
1323        !mirror::Throwable::GetJavaLangThrowable()->IsAssignableFrom(m->GetDeclaringClass())) {
1324      skipping_ = false;
1325    }
1326    if (!skipping_) {
1327      if (!m->IsRuntimeMethod()) {  // Ignore runtime frames (in particular callee save).
1328        ++depth_;
1329      }
1330    } else {
1331      ++skip_depth_;
1332    }
1333    return true;
1334  }
1335
1336  int GetDepth() const {
1337    return depth_;
1338  }
1339
1340  int GetSkipDepth() const {
1341    return skip_depth_;
1342  }
1343
1344 private:
1345  uint32_t depth_;
1346  uint32_t skip_depth_;
1347  bool skipping_;
1348};
1349
1350template<bool kTransactionActive>
1351class BuildInternalStackTraceVisitor : public StackVisitor {
1352 public:
1353  explicit BuildInternalStackTraceVisitor(Thread* self, Thread* thread, int skip_depth)
1354      : StackVisitor(thread, nullptr), self_(self),
1355        skip_depth_(skip_depth), count_(0), dex_pc_trace_(nullptr), method_trace_(nullptr) {}
1356
1357  bool Init(int depth)
1358      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1359    // Allocate method trace with an extra slot that will hold the PC trace
1360    SirtRef<mirror::ObjectArray<mirror::Object> >
1361        method_trace(self_,
1362                     Runtime::Current()->GetClassLinker()->AllocObjectArray<mirror::Object>(self_,
1363                                                                                            depth + 1));
1364    if (method_trace.get() == nullptr) {
1365      return false;
1366    }
1367    mirror::IntArray* dex_pc_trace = mirror::IntArray::Alloc(self_, depth);
1368    if (dex_pc_trace == nullptr) {
1369      return false;
1370    }
1371    // Save PC trace in last element of method trace, also places it into the
1372    // object graph.
1373    // We are called from native: use non-transactional mode.
1374    method_trace->Set<kTransactionActive>(depth, dex_pc_trace);
1375    // Set the Object*s and assert that no thread suspension is now possible.
1376    const char* last_no_suspend_cause =
1377        self_->StartAssertNoThreadSuspension("Building internal stack trace");
1378    CHECK(last_no_suspend_cause == nullptr) << last_no_suspend_cause;
1379    method_trace_ = method_trace.get();
1380    dex_pc_trace_ = dex_pc_trace;
1381    return true;
1382  }
1383
1384  virtual ~BuildInternalStackTraceVisitor() {
1385    if (method_trace_ != nullptr) {
1386      self_->EndAssertNoThreadSuspension(nullptr);
1387    }
1388  }
1389
1390  bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1391    if (method_trace_ == nullptr || dex_pc_trace_ == nullptr) {
1392      return true;  // We're probably trying to fillInStackTrace for an OutOfMemoryError.
1393    }
1394    if (skip_depth_ > 0) {
1395      skip_depth_--;
1396      return true;
1397    }
1398    mirror::ArtMethod* m = GetMethod();
1399    if (m->IsRuntimeMethod()) {
1400      return true;  // Ignore runtime frames (in particular callee save).
1401    }
1402    method_trace_->Set<kTransactionActive>(count_, m);
1403    dex_pc_trace_->Set<kTransactionActive>(count_,
1404        m->IsProxyMethod() ? DexFile::kDexNoIndex : GetDexPc());
1405    ++count_;
1406    return true;
1407  }
1408
1409  mirror::ObjectArray<mirror::Object>* GetInternalStackTrace() const {
1410    return method_trace_;
1411  }
1412
1413 private:
1414  Thread* const self_;
1415  // How many more frames to skip.
1416  int32_t skip_depth_;
1417  // Current position down stack trace.
1418  uint32_t count_;
1419  // Array of dex PC values.
1420  mirror::IntArray* dex_pc_trace_;
1421  // An array of the methods on the stack, the last entry is a reference to the PC trace.
1422  mirror::ObjectArray<mirror::Object>* method_trace_;
1423};
1424
1425template<bool kTransactionActive>
1426jobject Thread::CreateInternalStackTrace(const ScopedObjectAccessUnchecked& soa) const {
1427  // Compute depth of stack
1428  CountStackDepthVisitor count_visitor(const_cast<Thread*>(this));
1429  count_visitor.WalkStack();
1430  int32_t depth = count_visitor.GetDepth();
1431  int32_t skip_depth = count_visitor.GetSkipDepth();
1432
1433  // Build internal stack trace.
1434  BuildInternalStackTraceVisitor<kTransactionActive> build_trace_visitor(soa.Self(),
1435                                                                         const_cast<Thread*>(this),
1436                                                                         skip_depth);
1437  if (!build_trace_visitor.Init(depth)) {
1438    return nullptr;  // Allocation failed.
1439  }
1440  build_trace_visitor.WalkStack();
1441  mirror::ObjectArray<mirror::Object>* trace = build_trace_visitor.GetInternalStackTrace();
1442  if (kIsDebugBuild) {
1443    for (int32_t i = 0; i < trace->GetLength(); ++i) {
1444      CHECK(trace->Get(i) != nullptr);
1445    }
1446  }
1447  return soa.AddLocalReference<jobjectArray>(trace);
1448}
1449template jobject Thread::CreateInternalStackTrace<false>(const ScopedObjectAccessUnchecked& soa) const;
1450template jobject Thread::CreateInternalStackTrace<true>(const ScopedObjectAccessUnchecked& soa) const;
1451
1452jobjectArray Thread::InternalStackTraceToStackTraceElementArray(const ScopedObjectAccess& soa,
1453    jobject internal, jobjectArray output_array, int* stack_depth) {
1454  // Decode the internal stack trace into the depth, method trace and PC trace
1455  int32_t depth = soa.Decode<mirror::ObjectArray<mirror::Object>*>(internal)->GetLength() - 1;
1456
1457  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
1458
1459  jobjectArray result;
1460
1461  if (output_array != nullptr) {
1462    // Reuse the array we were given.
1463    result = output_array;
1464    // ...adjusting the number of frames we'll write to not exceed the array length.
1465    const int32_t traces_length =
1466        soa.Decode<mirror::ObjectArray<mirror::StackTraceElement>*>(result)->GetLength();
1467    depth = std::min(depth, traces_length);
1468  } else {
1469    // Create java_trace array and place in local reference table
1470    mirror::ObjectArray<mirror::StackTraceElement>* java_traces =
1471        class_linker->AllocStackTraceElementArray(soa.Self(), depth);
1472    if (java_traces == nullptr) {
1473      return nullptr;
1474    }
1475    result = soa.AddLocalReference<jobjectArray>(java_traces);
1476  }
1477
1478  if (stack_depth != nullptr) {
1479    *stack_depth = depth;
1480  }
1481
1482  for (int32_t i = 0; i < depth; ++i) {
1483    mirror::ObjectArray<mirror::Object>* method_trace =
1484          soa.Decode<mirror::ObjectArray<mirror::Object>*>(internal);
1485    // Prepare parameters for StackTraceElement(String cls, String method, String file, int line)
1486    mirror::ArtMethod* method = down_cast<mirror::ArtMethod*>(method_trace->Get(i));
1487    MethodHelper mh(method);
1488    int32_t line_number;
1489    SirtRef<mirror::String> class_name_object(soa.Self(), nullptr);
1490    SirtRef<mirror::String> source_name_object(soa.Self(), nullptr);
1491    if (method->IsProxyMethod()) {
1492      line_number = -1;
1493      class_name_object.reset(method->GetDeclaringClass()->GetName());
1494      // source_name_object intentionally left null for proxy methods
1495    } else {
1496      mirror::IntArray* pc_trace = down_cast<mirror::IntArray*>(method_trace->Get(depth));
1497      uint32_t dex_pc = pc_trace->Get(i);
1498      line_number = mh.GetLineNumFromDexPC(dex_pc);
1499      // Allocate element, potentially triggering GC
1500      // TODO: reuse class_name_object via Class::name_?
1501      const char* descriptor = mh.GetDeclaringClassDescriptor();
1502      CHECK(descriptor != nullptr);
1503      std::string class_name(PrettyDescriptor(descriptor));
1504      class_name_object.reset(mirror::String::AllocFromModifiedUtf8(soa.Self(), class_name.c_str()));
1505      if (class_name_object.get() == nullptr) {
1506        return nullptr;
1507      }
1508      const char* source_file = mh.GetDeclaringClassSourceFile();
1509      if (source_file != nullptr) {
1510        source_name_object.reset(mirror::String::AllocFromModifiedUtf8(soa.Self(), source_file));
1511        if (source_name_object.get() == nullptr) {
1512          return nullptr;
1513        }
1514      }
1515    }
1516    const char* method_name = mh.GetName();
1517    CHECK(method_name != nullptr);
1518    SirtRef<mirror::String> method_name_object(soa.Self(),
1519                                               mirror::String::AllocFromModifiedUtf8(soa.Self(),
1520                                                                                     method_name));
1521    if (method_name_object.get() == nullptr) {
1522      return nullptr;
1523    }
1524    mirror::StackTraceElement* obj = mirror::StackTraceElement::Alloc(
1525        soa.Self(), class_name_object, method_name_object, source_name_object, line_number);
1526    if (obj == nullptr) {
1527      return nullptr;
1528    }
1529    // We are called from native: use non-transactional mode.
1530    soa.Decode<mirror::ObjectArray<mirror::StackTraceElement>*>(result)->Set<false>(i, obj);
1531  }
1532  return result;
1533}
1534
1535void Thread::ThrowNewExceptionF(const ThrowLocation& throw_location,
1536                                const char* exception_class_descriptor, const char* fmt, ...) {
1537  va_list args;
1538  va_start(args, fmt);
1539  ThrowNewExceptionV(throw_location, exception_class_descriptor,
1540                     fmt, args);
1541  va_end(args);
1542}
1543
1544void Thread::ThrowNewExceptionV(const ThrowLocation& throw_location,
1545                                const char* exception_class_descriptor,
1546                                const char* fmt, va_list ap) {
1547  std::string msg;
1548  StringAppendV(&msg, fmt, ap);
1549  ThrowNewException(throw_location, exception_class_descriptor, msg.c_str());
1550}
1551
1552void Thread::ThrowNewException(const ThrowLocation& throw_location, const char* exception_class_descriptor,
1553                               const char* msg) {
1554  // Callers should either clear or call ThrowNewWrappedException.
1555  AssertNoPendingExceptionForNewException(msg);
1556  ThrowNewWrappedException(throw_location, exception_class_descriptor, msg);
1557}
1558
1559void Thread::ThrowNewWrappedException(const ThrowLocation& throw_location,
1560                                      const char* exception_class_descriptor,
1561                                      const char* msg) {
1562  DCHECK_EQ(this, Thread::Current());
1563  ScopedObjectAccessUnchecked soa(this);
1564  // Ensure we don't forget arguments over object allocation.
1565  SirtRef<mirror::Object> saved_throw_this(this, throw_location.GetThis());
1566  SirtRef<mirror::ArtMethod> saved_throw_method(this, throw_location.GetMethod());
1567  // Ignore the cause throw location. TODO: should we report this as a re-throw?
1568  ScopedLocalRef<jobject> cause(GetJniEnv(), soa.AddLocalReference<jobject>(GetException(nullptr)));
1569  ClearException();
1570  Runtime* runtime = Runtime::Current();
1571
1572  mirror::ClassLoader* cl = nullptr;
1573  if (saved_throw_method.get() != nullptr) {
1574    cl = saved_throw_method.get()->GetDeclaringClass()->GetClassLoader();
1575  }
1576  SirtRef<mirror::ClassLoader> class_loader(this, cl);
1577  SirtRef<mirror::Class>
1578      exception_class(this, runtime->GetClassLinker()->FindClass(this, exception_class_descriptor,
1579                                                                 class_loader));
1580  if (UNLIKELY(exception_class.get() == nullptr)) {
1581    CHECK(IsExceptionPending());
1582    LOG(ERROR) << "No exception class " << PrettyDescriptor(exception_class_descriptor);
1583    return;
1584  }
1585
1586  if (UNLIKELY(!runtime->GetClassLinker()->EnsureInitialized(exception_class, true, true))) {
1587    DCHECK(IsExceptionPending());
1588    return;
1589  }
1590  DCHECK(!runtime->IsStarted() || exception_class->IsThrowableClass());
1591  SirtRef<mirror::Throwable> exception(this,
1592                                down_cast<mirror::Throwable*>(exception_class->AllocObject(this)));
1593
1594  // If we couldn't allocate the exception, throw the pre-allocated out of memory exception.
1595  if (exception.get() == nullptr) {
1596    ThrowLocation gc_safe_throw_location(saved_throw_this.get(), saved_throw_method.get(),
1597                                         throw_location.GetDexPc());
1598    SetException(gc_safe_throw_location, Runtime::Current()->GetPreAllocatedOutOfMemoryError());
1599    return;
1600  }
1601
1602  // Choose an appropriate constructor and set up the arguments.
1603  const char* signature;
1604  ScopedLocalRef<jstring> msg_string(GetJniEnv(), nullptr);
1605  if (msg != nullptr) {
1606    // Ensure we remember this and the method over the String allocation.
1607    msg_string.reset(
1608        soa.AddLocalReference<jstring>(mirror::String::AllocFromModifiedUtf8(this, msg)));
1609    if (UNLIKELY(msg_string.get() == nullptr)) {
1610      CHECK(IsExceptionPending());  // OOME.
1611      return;
1612    }
1613    if (cause.get() == nullptr) {
1614      signature = "(Ljava/lang/String;)V";
1615    } else {
1616      signature = "(Ljava/lang/String;Ljava/lang/Throwable;)V";
1617    }
1618  } else {
1619    if (cause.get() == nullptr) {
1620      signature = "()V";
1621    } else {
1622      signature = "(Ljava/lang/Throwable;)V";
1623    }
1624  }
1625  mirror::ArtMethod* exception_init_method =
1626      exception_class->FindDeclaredDirectMethod("<init>", signature);
1627
1628  CHECK(exception_init_method != nullptr) << "No <init>" << signature << " in "
1629      << PrettyDescriptor(exception_class_descriptor);
1630
1631  if (UNLIKELY(!runtime->IsStarted())) {
1632    // Something is trying to throw an exception without a started runtime, which is the common
1633    // case in the compiler. We won't be able to invoke the constructor of the exception, so set
1634    // the exception fields directly.
1635    if (msg != nullptr) {
1636      exception->SetDetailMessage(down_cast<mirror::String*>(DecodeJObject(msg_string.get())));
1637    }
1638    if (cause.get() != nullptr) {
1639      exception->SetCause(down_cast<mirror::Throwable*>(DecodeJObject(cause.get())));
1640    }
1641    ThrowLocation gc_safe_throw_location(saved_throw_this.get(), saved_throw_method.get(),
1642                                         throw_location.GetDexPc());
1643    SetException(gc_safe_throw_location, exception.get());
1644  } else {
1645    jvalue jv_args[2];
1646    size_t i = 0;
1647
1648    if (msg != nullptr) {
1649      jv_args[i].l = msg_string.get();
1650      ++i;
1651    }
1652    if (cause.get() != nullptr) {
1653      jv_args[i].l = cause.get();
1654      ++i;
1655    }
1656    InvokeWithJValues(soa, exception.get(), soa.EncodeMethod(exception_init_method), jv_args);
1657    if (LIKELY(!IsExceptionPending())) {
1658      ThrowLocation gc_safe_throw_location(saved_throw_this.get(), saved_throw_method.get(),
1659                                           throw_location.GetDexPc());
1660      SetException(gc_safe_throw_location, exception.get());
1661    }
1662  }
1663}
1664
1665void Thread::ThrowOutOfMemoryError(const char* msg) {
1666  LOG(ERROR) << StringPrintf("Throwing OutOfMemoryError \"%s\"%s",
1667      msg, (tls32_.throwing_OutOfMemoryError ? " (recursive case)" : ""));
1668  ThrowLocation throw_location = GetCurrentLocationForThrow();
1669  if (!tls32_.throwing_OutOfMemoryError) {
1670    tls32_.throwing_OutOfMemoryError = true;
1671    ThrowNewException(throw_location, "Ljava/lang/OutOfMemoryError;", msg);
1672    tls32_.throwing_OutOfMemoryError = false;
1673  } else {
1674    Dump(LOG(ERROR));  // The pre-allocated OOME has no stack, so help out and log one.
1675    SetException(throw_location, Runtime::Current()->GetPreAllocatedOutOfMemoryError());
1676  }
1677}
1678
1679Thread* Thread::CurrentFromGdb() {
1680  return Thread::Current();
1681}
1682
1683void Thread::DumpFromGdb() const {
1684  std::ostringstream ss;
1685  Dump(ss);
1686  std::string str(ss.str());
1687  // log to stderr for debugging command line processes
1688  std::cerr << str;
1689#ifdef HAVE_ANDROID_OS
1690  // log to logcat for debugging frameworks processes
1691  LOG(INFO) << str;
1692#endif
1693}
1694
1695// Explicitly instantiate 32 and 64bit thread offset dumping support.
1696template void Thread::DumpThreadOffset<4>(std::ostream& os, uint32_t offset);
1697template void Thread::DumpThreadOffset<8>(std::ostream& os, uint32_t offset);
1698
1699template<size_t ptr_size>
1700void Thread::DumpThreadOffset(std::ostream& os, uint32_t offset) {
1701#define DO_THREAD_OFFSET(x, y) \
1702    if (offset == x.Uint32Value()) { \
1703      os << y; \
1704      return; \
1705    }
1706  DO_THREAD_OFFSET(ThreadFlagsOffset<ptr_size>(), "state_and_flags")
1707  DO_THREAD_OFFSET(CardTableOffset<ptr_size>(), "card_table")
1708  DO_THREAD_OFFSET(ExceptionOffset<ptr_size>(), "exception")
1709  DO_THREAD_OFFSET(PeerOffset<ptr_size>(), "peer");
1710  DO_THREAD_OFFSET(JniEnvOffset<ptr_size>(), "jni_env")
1711  DO_THREAD_OFFSET(SelfOffset<ptr_size>(), "self")
1712  DO_THREAD_OFFSET(StackEndOffset<ptr_size>(), "stack_end")
1713  DO_THREAD_OFFSET(ThinLockIdOffset<ptr_size>(), "thin_lock_thread_id")
1714  DO_THREAD_OFFSET(TopOfManagedStackOffset<ptr_size>(), "top_quick_frame_method")
1715  DO_THREAD_OFFSET(TopOfManagedStackPcOffset<ptr_size>(), "top_quick_frame_pc")
1716  DO_THREAD_OFFSET(TopShadowFrameOffset<ptr_size>(), "top_shadow_frame")
1717  DO_THREAD_OFFSET(TopSirtOffset<ptr_size>(), "top_sirt")
1718  DO_THREAD_OFFSET(ThreadSuspendTriggerOffset<ptr_size>(), "suspend_trigger")
1719#undef DO_THREAD_OFFSET
1720
1721#define INTERPRETER_ENTRY_POINT_INFO(x) \
1722    if (INTERPRETER_ENTRYPOINT_OFFSET(ptr_size, x).Uint32Value() == offset) { \
1723      os << #x; \
1724      return; \
1725    }
1726  INTERPRETER_ENTRY_POINT_INFO(pInterpreterToInterpreterBridge)
1727  INTERPRETER_ENTRY_POINT_INFO(pInterpreterToCompiledCodeBridge)
1728#undef INTERPRETER_ENTRY_POINT_INFO
1729
1730#define JNI_ENTRY_POINT_INFO(x) \
1731    if (JNI_ENTRYPOINT_OFFSET(ptr_size, x).Uint32Value() == offset) { \
1732      os << #x; \
1733      return; \
1734    }
1735  JNI_ENTRY_POINT_INFO(pDlsymLookup)
1736#undef JNI_ENTRY_POINT_INFO
1737
1738#define PORTABLE_ENTRY_POINT_INFO(x) \
1739    if (PORTABLE_ENTRYPOINT_OFFSET(ptr_size, x).Uint32Value() == offset) { \
1740      os << #x; \
1741      return; \
1742    }
1743  PORTABLE_ENTRY_POINT_INFO(pPortableImtConflictTrampoline)
1744  PORTABLE_ENTRY_POINT_INFO(pPortableResolutionTrampoline)
1745  PORTABLE_ENTRY_POINT_INFO(pPortableToInterpreterBridge)
1746#undef PORTABLE_ENTRY_POINT_INFO
1747
1748#define QUICK_ENTRY_POINT_INFO(x) \
1749    if (QUICK_ENTRYPOINT_OFFSET(ptr_size, x).Uint32Value() == offset) { \
1750      os << #x; \
1751      return; \
1752    }
1753  QUICK_ENTRY_POINT_INFO(pAllocArray)
1754  QUICK_ENTRY_POINT_INFO(pAllocArrayResolved)
1755  QUICK_ENTRY_POINT_INFO(pAllocArrayWithAccessCheck)
1756  QUICK_ENTRY_POINT_INFO(pAllocObject)
1757  QUICK_ENTRY_POINT_INFO(pAllocObjectResolved)
1758  QUICK_ENTRY_POINT_INFO(pAllocObjectInitialized)
1759  QUICK_ENTRY_POINT_INFO(pAllocObjectWithAccessCheck)
1760  QUICK_ENTRY_POINT_INFO(pCheckAndAllocArray)
1761  QUICK_ENTRY_POINT_INFO(pCheckAndAllocArrayWithAccessCheck)
1762  QUICK_ENTRY_POINT_INFO(pInstanceofNonTrivial)
1763  QUICK_ENTRY_POINT_INFO(pCheckCast)
1764  QUICK_ENTRY_POINT_INFO(pInitializeStaticStorage)
1765  QUICK_ENTRY_POINT_INFO(pInitializeTypeAndVerifyAccess)
1766  QUICK_ENTRY_POINT_INFO(pInitializeType)
1767  QUICK_ENTRY_POINT_INFO(pResolveString)
1768  QUICK_ENTRY_POINT_INFO(pSet32Instance)
1769  QUICK_ENTRY_POINT_INFO(pSet32Static)
1770  QUICK_ENTRY_POINT_INFO(pSet64Instance)
1771  QUICK_ENTRY_POINT_INFO(pSet64Static)
1772  QUICK_ENTRY_POINT_INFO(pSetObjInstance)
1773  QUICK_ENTRY_POINT_INFO(pSetObjStatic)
1774  QUICK_ENTRY_POINT_INFO(pGet32Instance)
1775  QUICK_ENTRY_POINT_INFO(pGet32Static)
1776  QUICK_ENTRY_POINT_INFO(pGet64Instance)
1777  QUICK_ENTRY_POINT_INFO(pGet64Static)
1778  QUICK_ENTRY_POINT_INFO(pGetObjInstance)
1779  QUICK_ENTRY_POINT_INFO(pGetObjStatic)
1780  QUICK_ENTRY_POINT_INFO(pAputObjectWithNullAndBoundCheck)
1781  QUICK_ENTRY_POINT_INFO(pAputObjectWithBoundCheck)
1782  QUICK_ENTRY_POINT_INFO(pAputObject)
1783  QUICK_ENTRY_POINT_INFO(pHandleFillArrayData)
1784  QUICK_ENTRY_POINT_INFO(pJniMethodStart)
1785  QUICK_ENTRY_POINT_INFO(pJniMethodStartSynchronized)
1786  QUICK_ENTRY_POINT_INFO(pJniMethodEnd)
1787  QUICK_ENTRY_POINT_INFO(pJniMethodEndSynchronized)
1788  QUICK_ENTRY_POINT_INFO(pJniMethodEndWithReference)
1789  QUICK_ENTRY_POINT_INFO(pJniMethodEndWithReferenceSynchronized)
1790  QUICK_ENTRY_POINT_INFO(pQuickGenericJniTrampoline)
1791  QUICK_ENTRY_POINT_INFO(pLockObject)
1792  QUICK_ENTRY_POINT_INFO(pUnlockObject)
1793  QUICK_ENTRY_POINT_INFO(pCmpgDouble)
1794  QUICK_ENTRY_POINT_INFO(pCmpgFloat)
1795  QUICK_ENTRY_POINT_INFO(pCmplDouble)
1796  QUICK_ENTRY_POINT_INFO(pCmplFloat)
1797  QUICK_ENTRY_POINT_INFO(pFmod)
1798  QUICK_ENTRY_POINT_INFO(pSqrt)
1799  QUICK_ENTRY_POINT_INFO(pL2d)
1800  QUICK_ENTRY_POINT_INFO(pFmodf)
1801  QUICK_ENTRY_POINT_INFO(pL2f)
1802  QUICK_ENTRY_POINT_INFO(pD2iz)
1803  QUICK_ENTRY_POINT_INFO(pF2iz)
1804  QUICK_ENTRY_POINT_INFO(pIdivmod)
1805  QUICK_ENTRY_POINT_INFO(pD2l)
1806  QUICK_ENTRY_POINT_INFO(pF2l)
1807  QUICK_ENTRY_POINT_INFO(pLdiv)
1808  QUICK_ENTRY_POINT_INFO(pLmod)
1809  QUICK_ENTRY_POINT_INFO(pLmul)
1810  QUICK_ENTRY_POINT_INFO(pShlLong)
1811  QUICK_ENTRY_POINT_INFO(pShrLong)
1812  QUICK_ENTRY_POINT_INFO(pUshrLong)
1813  QUICK_ENTRY_POINT_INFO(pIndexOf)
1814  QUICK_ENTRY_POINT_INFO(pMemcmp16)
1815  QUICK_ENTRY_POINT_INFO(pStringCompareTo)
1816  QUICK_ENTRY_POINT_INFO(pMemcpy)
1817  QUICK_ENTRY_POINT_INFO(pQuickImtConflictTrampoline)
1818  QUICK_ENTRY_POINT_INFO(pQuickResolutionTrampoline)
1819  QUICK_ENTRY_POINT_INFO(pQuickToInterpreterBridge)
1820  QUICK_ENTRY_POINT_INFO(pInvokeDirectTrampolineWithAccessCheck)
1821  QUICK_ENTRY_POINT_INFO(pInvokeInterfaceTrampolineWithAccessCheck)
1822  QUICK_ENTRY_POINT_INFO(pInvokeStaticTrampolineWithAccessCheck)
1823  QUICK_ENTRY_POINT_INFO(pInvokeSuperTrampolineWithAccessCheck)
1824  QUICK_ENTRY_POINT_INFO(pInvokeVirtualTrampolineWithAccessCheck)
1825  QUICK_ENTRY_POINT_INFO(pCheckSuspend)
1826  QUICK_ENTRY_POINT_INFO(pTestSuspend)
1827  QUICK_ENTRY_POINT_INFO(pDeliverException)
1828  QUICK_ENTRY_POINT_INFO(pThrowArrayBounds)
1829  QUICK_ENTRY_POINT_INFO(pThrowDivZero)
1830  QUICK_ENTRY_POINT_INFO(pThrowNoSuchMethod)
1831  QUICK_ENTRY_POINT_INFO(pThrowNullPointer)
1832  QUICK_ENTRY_POINT_INFO(pThrowStackOverflow)
1833#undef QUICK_ENTRY_POINT_INFO
1834
1835  os << offset;
1836}
1837
1838void Thread::QuickDeliverException() {
1839  // Get exception from thread.
1840  ThrowLocation throw_location;
1841  mirror::Throwable* exception = GetException(&throw_location);
1842  CHECK(exception != nullptr);
1843  // Don't leave exception visible while we try to find the handler, which may cause class
1844  // resolution.
1845  ClearException();
1846  bool is_deoptimization = (exception == GetDeoptimizationException());
1847  if (kDebugExceptionDelivery) {
1848    if (!is_deoptimization) {
1849      mirror::String* msg = exception->GetDetailMessage();
1850      std::string str_msg(msg != nullptr ? msg->ToModifiedUtf8() : "");
1851      DumpStack(LOG(INFO) << "Delivering exception: " << PrettyTypeOf(exception)
1852                << ": " << str_msg << "\n");
1853    } else {
1854      DumpStack(LOG(INFO) << "Deoptimizing: ");
1855    }
1856  }
1857  QuickExceptionHandler exception_handler(this, is_deoptimization);
1858  if (is_deoptimization) {
1859    exception_handler.DeoptimizeStack();
1860  } else {
1861    exception_handler.FindCatch(throw_location, exception);
1862  }
1863  exception_handler.UpdateInstrumentationStack();
1864  exception_handler.DoLongJump();
1865  LOG(FATAL) << "UNREACHABLE";
1866}
1867
1868Context* Thread::GetLongJumpContext() {
1869  Context* result = tlsPtr_.long_jump_context;
1870  if (result == nullptr) {
1871    result = Context::Create();
1872  } else {
1873    tlsPtr_.long_jump_context = nullptr;  // Avoid context being shared.
1874    result->Reset();
1875  }
1876  return result;
1877}
1878
1879struct CurrentMethodVisitor FINAL : public StackVisitor {
1880  CurrentMethodVisitor(Thread* thread, Context* context)
1881      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
1882      : StackVisitor(thread, context), this_object_(nullptr), method_(nullptr), dex_pc_(0) {}
1883  bool VisitFrame() OVERRIDE SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1884    mirror::ArtMethod* m = GetMethod();
1885    if (m->IsRuntimeMethod()) {
1886      // Continue if this is a runtime method.
1887      return true;
1888    }
1889    if (context_ != nullptr) {
1890      this_object_ = GetThisObject();
1891    }
1892    method_ = m;
1893    dex_pc_ = GetDexPc();
1894    return false;
1895  }
1896  mirror::Object* this_object_;
1897  mirror::ArtMethod* method_;
1898  uint32_t dex_pc_;
1899};
1900
1901mirror::ArtMethod* Thread::GetCurrentMethod(uint32_t* dex_pc) const {
1902  CurrentMethodVisitor visitor(const_cast<Thread*>(this), nullptr);
1903  visitor.WalkStack(false);
1904  if (dex_pc != nullptr) {
1905    *dex_pc = visitor.dex_pc_;
1906  }
1907  return visitor.method_;
1908}
1909
1910ThrowLocation Thread::GetCurrentLocationForThrow() {
1911  Context* context = GetLongJumpContext();
1912  CurrentMethodVisitor visitor(this, context);
1913  visitor.WalkStack(false);
1914  ReleaseLongJumpContext(context);
1915  return ThrowLocation(visitor.this_object_, visitor.method_, visitor.dex_pc_);
1916}
1917
1918bool Thread::HoldsLock(mirror::Object* object) const {
1919  if (object == nullptr) {
1920    return false;
1921  }
1922  return object->GetLockOwnerThreadId() == GetThreadId();
1923}
1924
1925// RootVisitor parameters are: (const Object* obj, size_t vreg, const StackVisitor* visitor).
1926template <typename RootVisitor>
1927class ReferenceMapVisitor : public StackVisitor {
1928 public:
1929  ReferenceMapVisitor(Thread* thread, Context* context, const RootVisitor& visitor)
1930      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
1931      : StackVisitor(thread, context), visitor_(visitor) {}
1932
1933  bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1934    if (false) {
1935      LOG(INFO) << "Visiting stack roots in " << PrettyMethod(GetMethod())
1936                << StringPrintf("@ PC:%04x", GetDexPc());
1937    }
1938    ShadowFrame* shadow_frame = GetCurrentShadowFrame();
1939    if (shadow_frame != nullptr) {
1940      VisitShadowFrame(shadow_frame);
1941    } else {
1942      VisitQuickFrame();
1943    }
1944    return true;
1945  }
1946
1947  void VisitShadowFrame(ShadowFrame* shadow_frame) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1948    mirror::ArtMethod* m = shadow_frame->GetMethod();
1949    size_t num_regs = shadow_frame->NumberOfVRegs();
1950    if (m->IsNative() || shadow_frame->HasReferenceArray()) {
1951      // SIRT for JNI or References for interpreter.
1952      for (size_t reg = 0; reg < num_regs; ++reg) {
1953        mirror::Object* ref = shadow_frame->GetVRegReference(reg);
1954        if (ref != nullptr) {
1955          mirror::Object* new_ref = ref;
1956          visitor_(&new_ref, reg, this);
1957          if (new_ref != ref) {
1958            shadow_frame->SetVRegReference(reg, new_ref);
1959          }
1960        }
1961      }
1962    } else {
1963      // Java method.
1964      // Portable path use DexGcMap and store in Method.native_gc_map_.
1965      const uint8_t* gc_map = m->GetNativeGcMap();
1966      CHECK(gc_map != nullptr) << PrettyMethod(m);
1967      verifier::DexPcToReferenceMap dex_gc_map(gc_map);
1968      uint32_t dex_pc = shadow_frame->GetDexPC();
1969      const uint8_t* reg_bitmap = dex_gc_map.FindBitMap(dex_pc);
1970      DCHECK(reg_bitmap != nullptr);
1971      num_regs = std::min(dex_gc_map.RegWidth() * 8, num_regs);
1972      for (size_t reg = 0; reg < num_regs; ++reg) {
1973        if (TestBitmap(reg, reg_bitmap)) {
1974          mirror::Object* ref = shadow_frame->GetVRegReference(reg);
1975          if (ref != nullptr) {
1976            mirror::Object* new_ref = ref;
1977            visitor_(&new_ref, reg, this);
1978            if (new_ref != ref) {
1979              shadow_frame->SetVRegReference(reg, new_ref);
1980            }
1981          }
1982        }
1983      }
1984    }
1985  }
1986
1987 private:
1988  void VisitQuickFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1989    mirror::ArtMethod* m = GetMethod();
1990    // Process register map (which native and runtime methods don't have)
1991    if (!m->IsNative() && !m->IsRuntimeMethod() && !m->IsProxyMethod()) {
1992      const uint8_t* native_gc_map = m->GetNativeGcMap();
1993      CHECK(native_gc_map != nullptr) << PrettyMethod(m);
1994      mh_.ChangeMethod(m);
1995      const DexFile::CodeItem* code_item = mh_.GetCodeItem();
1996      DCHECK(code_item != nullptr) << PrettyMethod(m);  // Can't be nullptr or how would we compile its instructions?
1997      NativePcOffsetToReferenceMap map(native_gc_map);
1998      size_t num_regs = std::min(map.RegWidth() * 8,
1999                                 static_cast<size_t>(code_item->registers_size_));
2000      if (num_regs > 0) {
2001        const uint8_t* reg_bitmap = map.FindBitMap(GetNativePcOffset());
2002        DCHECK(reg_bitmap != nullptr);
2003        const VmapTable vmap_table(m->GetVmapTable());
2004        uint32_t core_spills = m->GetCoreSpillMask();
2005        uint32_t fp_spills = m->GetFpSpillMask();
2006        size_t frame_size = m->GetFrameSizeInBytes();
2007        // For all dex registers in the bitmap
2008        mirror::ArtMethod** cur_quick_frame = GetCurrentQuickFrame();
2009        DCHECK(cur_quick_frame != nullptr);
2010        for (size_t reg = 0; reg < num_regs; ++reg) {
2011          // Does this register hold a reference?
2012          if (TestBitmap(reg, reg_bitmap)) {
2013            uint32_t vmap_offset;
2014            if (vmap_table.IsInContext(reg, kReferenceVReg, &vmap_offset)) {
2015              int vmap_reg = vmap_table.ComputeRegister(core_spills, vmap_offset, kReferenceVReg);
2016              // This is sound as spilled GPRs will be word sized (ie 32 or 64bit).
2017              mirror::Object** ref_addr = reinterpret_cast<mirror::Object**>(GetGPRAddress(vmap_reg));
2018              if (*ref_addr != nullptr) {
2019                visitor_(ref_addr, reg, this);
2020              }
2021            } else {
2022              StackReference<mirror::Object>* ref_addr =
2023                  reinterpret_cast<StackReference<mirror::Object>*>(
2024                      GetVRegAddr(cur_quick_frame, code_item, core_spills, fp_spills, frame_size,
2025                                  reg));
2026              mirror::Object* ref = ref_addr->AsMirrorPtr();
2027              if (ref != nullptr) {
2028                mirror::Object* new_ref = ref;
2029                visitor_(&new_ref, reg, this);
2030                if (ref != new_ref) {
2031                  ref_addr->Assign(new_ref);
2032                }
2033              }
2034            }
2035          }
2036        }
2037      }
2038    }
2039  }
2040
2041  static bool TestBitmap(size_t reg, const uint8_t* reg_vector) {
2042    return ((reg_vector[reg / kBitsPerByte] >> (reg % kBitsPerByte)) & 0x01) != 0;
2043  }
2044
2045  // Visitor for when we visit a root.
2046  const RootVisitor& visitor_;
2047
2048  // A method helper we keep around to avoid dex file/cache re-computations.
2049  MethodHelper mh_;
2050};
2051
2052class RootCallbackVisitor {
2053 public:
2054  RootCallbackVisitor(RootCallback* callback, void* arg, uint32_t tid)
2055     : callback_(callback), arg_(arg), tid_(tid) {}
2056
2057  void operator()(mirror::Object** obj, size_t, const StackVisitor*) const {
2058    callback_(obj, arg_, tid_, kRootJavaFrame);
2059  }
2060
2061 private:
2062  RootCallback* const callback_;
2063  void* const arg_;
2064  const uint32_t tid_;
2065};
2066
2067void Thread::SetClassLoaderOverride(mirror::ClassLoader* class_loader_override) {
2068  VerifyObject(class_loader_override);
2069  tlsPtr_.class_loader_override = class_loader_override;
2070}
2071
2072void Thread::VisitRoots(RootCallback* visitor, void* arg) {
2073  uint32_t thread_id = GetThreadId();
2074  if (tlsPtr_.opeer != nullptr) {
2075    visitor(&tlsPtr_.opeer, arg, thread_id, kRootThreadObject);
2076  }
2077  if (tlsPtr_.exception != nullptr && tlsPtr_.exception != GetDeoptimizationException()) {
2078    visitor(reinterpret_cast<mirror::Object**>(&tlsPtr_.exception), arg, thread_id, kRootNativeStack);
2079  }
2080  tlsPtr_.throw_location.VisitRoots(visitor, arg);
2081  if (tlsPtr_.class_loader_override != nullptr) {
2082    visitor(reinterpret_cast<mirror::Object**>(&tlsPtr_.class_loader_override), arg, thread_id,
2083            kRootNativeStack);
2084  }
2085  if (tlsPtr_.monitor_enter_object != nullptr) {
2086    visitor(&tlsPtr_.monitor_enter_object, arg, thread_id, kRootNativeStack);
2087  }
2088  tlsPtr_.jni_env->locals.VisitRoots(visitor, arg, thread_id, kRootJNILocal);
2089  tlsPtr_.jni_env->monitors.VisitRoots(visitor, arg, thread_id, kRootJNIMonitor);
2090  SirtVisitRoots(visitor, arg, thread_id);
2091  if (tlsPtr_.debug_invoke_req != nullptr) {
2092    tlsPtr_.debug_invoke_req->VisitRoots(visitor, arg, thread_id, kRootDebugger);
2093  }
2094  if (tlsPtr_.single_step_control != nullptr) {
2095    tlsPtr_.single_step_control->VisitRoots(visitor, arg, thread_id, kRootDebugger);
2096  }
2097  if (tlsPtr_.deoptimization_shadow_frame != nullptr) {
2098    RootCallbackVisitor visitorToCallback(visitor, arg, thread_id);
2099    ReferenceMapVisitor<RootCallbackVisitor> mapper(this, nullptr, visitorToCallback);
2100    for (ShadowFrame* shadow_frame = tlsPtr_.deoptimization_shadow_frame; shadow_frame != nullptr;
2101        shadow_frame = shadow_frame->GetLink()) {
2102      mapper.VisitShadowFrame(shadow_frame);
2103    }
2104  }
2105  // Visit roots on this thread's stack
2106  Context* context = GetLongJumpContext();
2107  RootCallbackVisitor visitorToCallback(visitor, arg, thread_id);
2108  ReferenceMapVisitor<RootCallbackVisitor> mapper(this, context, visitorToCallback);
2109  mapper.WalkStack();
2110  ReleaseLongJumpContext(context);
2111  for (instrumentation::InstrumentationStackFrame& frame : *GetInstrumentationStack()) {
2112    if (frame.this_object_ != nullptr) {
2113      visitor(&frame.this_object_, arg, thread_id, kRootJavaFrame);
2114    }
2115    DCHECK(frame.method_ != nullptr);
2116    visitor(reinterpret_cast<mirror::Object**>(&frame.method_), arg, thread_id, kRootJavaFrame);
2117  }
2118}
2119
2120static void VerifyRoot(mirror::Object** root, void* /*arg*/, uint32_t /*thread_id*/,
2121                       RootType /*root_type*/) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
2122  VerifyObject(*root);
2123}
2124
2125void Thread::VerifyStackImpl() {
2126  UniquePtr<Context> context(Context::Create());
2127  RootCallbackVisitor visitorToCallback(VerifyRoot, Runtime::Current()->GetHeap(), GetThreadId());
2128  ReferenceMapVisitor<RootCallbackVisitor> mapper(this, context.get(), visitorToCallback);
2129  mapper.WalkStack();
2130}
2131
2132// Set the stack end to that to be used during a stack overflow
2133void Thread::SetStackEndForStackOverflow() {
2134  // During stack overflow we allow use of the full stack.
2135  if (tlsPtr_.stack_end == tlsPtr_.stack_begin) {
2136    // However, we seem to have already extended to use the full stack.
2137    LOG(ERROR) << "Need to increase kStackOverflowReservedBytes (currently "
2138               << kStackOverflowReservedBytes << ")?";
2139    DumpStack(LOG(ERROR));
2140    LOG(FATAL) << "Recursive stack overflow.";
2141  }
2142
2143  tlsPtr_.stack_end = tlsPtr_.stack_begin;
2144}
2145
2146void Thread::SetTlab(byte* start, byte* end) {
2147  DCHECK_LE(start, end);
2148  tlsPtr_.thread_local_start = start;
2149  tlsPtr_.thread_local_pos  = tlsPtr_.thread_local_start;
2150  tlsPtr_.thread_local_end = end;
2151  tlsPtr_.thread_local_objects = 0;
2152}
2153
2154bool Thread::HasTlab() const {
2155  bool has_tlab = tlsPtr_.thread_local_pos != nullptr;
2156  if (has_tlab) {
2157    DCHECK(tlsPtr_.thread_local_start != nullptr && tlsPtr_.thread_local_end != nullptr);
2158  } else {
2159    DCHECK(tlsPtr_.thread_local_start == nullptr && tlsPtr_.thread_local_end == nullptr);
2160  }
2161  return has_tlab;
2162}
2163
2164std::ostream& operator<<(std::ostream& os, const Thread& thread) {
2165  thread.ShortDump(os);
2166  return os;
2167}
2168
2169}  // namespace art
2170