thread.cc revision 37f05ef45e0393de812d51261dc293240c17294d
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-inl.h" 36#include "class_linker.h" 37#include "debugger.h" 38#include "dex_file-inl.h" 39#include "entrypoints/entrypoint_utils.h" 40#include "entrypoints/quick/quick_alloc_entrypoints.h" 41#include "gc_map.h" 42#include "gc/accounting/card_table-inl.h" 43#include "gc/allocator/rosalloc.h" 44#include "gc/heap.h" 45#include "gc/space/space.h" 46#include "handle_scope-inl.h" 47#include "handle_scope.h" 48#include "indirect_reference_table-inl.h" 49#include "jni_internal.h" 50#include "mirror/art_field-inl.h" 51#include "mirror/art_method-inl.h" 52#include "mirror/class_loader.h" 53#include "mirror/class-inl.h" 54#include "mirror/object_array-inl.h" 55#include "mirror/stack_trace_element.h" 56#include "monitor.h" 57#include "object_lock.h" 58#include "quick_exception_handler.h" 59#include "quick/quick_method_frame_info.h" 60#include "reflection.h" 61#include "runtime.h" 62#include "scoped_thread_state_change.h" 63#include "ScopedLocalRef.h" 64#include "ScopedUtfChars.h" 65#include "stack.h" 66#include "thread_list.h" 67#include "thread-inl.h" 68#include "utils.h" 69#include "verifier/dex_gc_map.h" 70#include "verify_object-inl.h" 71#include "vmap_table.h" 72#include "well_known_classes.h" 73 74namespace art { 75 76bool Thread::is_started_ = false; 77pthread_key_t Thread::pthread_key_self_; 78ConditionVariable* Thread::resume_cond_ = nullptr; 79const size_t Thread::kStackOverflowImplicitCheckSize = GetStackOverflowReservedBytes(kRuntimeISA); 80 81static const char* kThreadNameDuringStartup = "<native thread without managed peer>"; 82 83void Thread::InitCardTable() { 84 tlsPtr_.card_table = Runtime::Current()->GetHeap()->GetCardTable()->GetBiasedBegin(); 85} 86 87static void UnimplementedEntryPoint() { 88 UNIMPLEMENTED(FATAL); 89} 90 91void InitEntryPoints(InterpreterEntryPoints* ipoints, JniEntryPoints* jpoints, 92 PortableEntryPoints* ppoints, QuickEntryPoints* qpoints); 93 94void Thread::InitTlsEntryPoints() { 95 // Insert a placeholder so we can easily tell if we call an unimplemented entry point. 96 uintptr_t* begin = reinterpret_cast<uintptr_t*>(&tlsPtr_.interpreter_entrypoints); 97 uintptr_t* end = reinterpret_cast<uintptr_t*>(reinterpret_cast<uint8_t*>(begin) + 98 sizeof(tlsPtr_.quick_entrypoints)); 99 for (uintptr_t* it = begin; it != end; ++it) { 100 *it = reinterpret_cast<uintptr_t>(UnimplementedEntryPoint); 101 } 102 InitEntryPoints(&tlsPtr_.interpreter_entrypoints, &tlsPtr_.jni_entrypoints, 103 &tlsPtr_.portable_entrypoints, &tlsPtr_.quick_entrypoints); 104} 105 106void Thread::ResetQuickAllocEntryPointsForThread() { 107 ResetQuickAllocEntryPoints(&tlsPtr_.quick_entrypoints); 108} 109 110void Thread::SetDeoptimizationShadowFrame(ShadowFrame* sf) { 111 tlsPtr_.deoptimization_shadow_frame = sf; 112} 113 114void Thread::SetDeoptimizationReturnValue(const JValue& ret_val) { 115 tls64_.deoptimization_return_value.SetJ(ret_val.GetJ()); 116} 117 118ShadowFrame* Thread::GetAndClearDeoptimizationShadowFrame(JValue* ret_val) { 119 ShadowFrame* sf = tlsPtr_.deoptimization_shadow_frame; 120 tlsPtr_.deoptimization_shadow_frame = nullptr; 121 ret_val->SetJ(tls64_.deoptimization_return_value.GetJ()); 122 return sf; 123} 124 125void Thread::SetShadowFrameUnderConstruction(ShadowFrame* sf) { 126 sf->SetLink(tlsPtr_.shadow_frame_under_construction); 127 tlsPtr_.shadow_frame_under_construction = sf; 128} 129 130void Thread::ClearShadowFrameUnderConstruction() { 131 CHECK_NE(static_cast<ShadowFrame*>(nullptr), tlsPtr_.shadow_frame_under_construction); 132 tlsPtr_.shadow_frame_under_construction = tlsPtr_.shadow_frame_under_construction->GetLink(); 133} 134 135void Thread::InitTid() { 136 tls32_.tid = ::art::GetTid(); 137} 138 139void Thread::InitAfterFork() { 140 // One thread (us) survived the fork, but we have a new tid so we need to 141 // update the value stashed in this Thread*. 142 InitTid(); 143} 144 145void* Thread::CreateCallback(void* arg) { 146 Thread* self = reinterpret_cast<Thread*>(arg); 147 Runtime* runtime = Runtime::Current(); 148 if (runtime == nullptr) { 149 LOG(ERROR) << "Thread attaching to non-existent runtime: " << *self; 150 return nullptr; 151 } 152 { 153 // TODO: pass self to MutexLock - requires self to equal Thread::Current(), which is only true 154 // after self->Init(). 155 MutexLock mu(nullptr, *Locks::runtime_shutdown_lock_); 156 // Check that if we got here we cannot be shutting down (as shutdown should never have started 157 // while threads are being born). 158 CHECK(!runtime->IsShuttingDownLocked()); 159 self->Init(runtime->GetThreadList(), runtime->GetJavaVM()); 160 Runtime::Current()->EndThreadBirth(); 161 } 162 { 163 ScopedObjectAccess soa(self); 164 165 // Copy peer into self, deleting global reference when done. 166 CHECK(self->tlsPtr_.jpeer != nullptr); 167 self->tlsPtr_.opeer = soa.Decode<mirror::Object*>(self->tlsPtr_.jpeer); 168 self->GetJniEnv()->DeleteGlobalRef(self->tlsPtr_.jpeer); 169 self->tlsPtr_.jpeer = nullptr; 170 self->SetThreadName(self->GetThreadName(soa)->ToModifiedUtf8().c_str()); 171 Dbg::PostThreadStart(self); 172 173 // Invoke the 'run' method of our java.lang.Thread. 174 mirror::Object* receiver = self->tlsPtr_.opeer; 175 jmethodID mid = WellKnownClasses::java_lang_Thread_run; 176 InvokeVirtualOrInterfaceWithJValues(soa, receiver, mid, nullptr); 177 } 178 // Detach and delete self. 179 Runtime::Current()->GetThreadList()->Unregister(self); 180 181 return nullptr; 182} 183 184Thread* Thread::FromManagedThread(const ScopedObjectAccessAlreadyRunnable& soa, 185 mirror::Object* thread_peer) { 186 mirror::ArtField* f = soa.DecodeField(WellKnownClasses::java_lang_Thread_nativePeer); 187 Thread* result = reinterpret_cast<Thread*>(static_cast<uintptr_t>(f->GetLong(thread_peer))); 188 // Sanity check that if we have a result it is either suspended or we hold the thread_list_lock_ 189 // to stop it from going away. 190 if (kIsDebugBuild) { 191 MutexLock mu(soa.Self(), *Locks::thread_suspend_count_lock_); 192 if (result != nullptr && !result->IsSuspended()) { 193 Locks::thread_list_lock_->AssertHeld(soa.Self()); 194 } 195 } 196 return result; 197} 198 199Thread* Thread::FromManagedThread(const ScopedObjectAccessAlreadyRunnable& soa, 200 jobject java_thread) { 201 return FromManagedThread(soa, soa.Decode<mirror::Object*>(java_thread)); 202} 203 204static size_t FixStackSize(size_t stack_size) { 205 // A stack size of zero means "use the default". 206 if (stack_size == 0) { 207 stack_size = Runtime::Current()->GetDefaultStackSize(); 208 } 209 210 // Dalvik used the bionic pthread default stack size for native threads, 211 // so include that here to support apps that expect large native stacks. 212 stack_size += 1 * MB; 213 214 // It's not possible to request a stack smaller than the system-defined PTHREAD_STACK_MIN. 215 if (stack_size < PTHREAD_STACK_MIN) { 216 stack_size = PTHREAD_STACK_MIN; 217 } 218 219 if (Runtime::Current()->ExplicitStackOverflowChecks()) { 220 // It's likely that callers are trying to ensure they have at least a certain amount of 221 // stack space, so we should add our reserved space on top of what they requested, rather 222 // than implicitly take it away from them. 223 stack_size += GetStackOverflowReservedBytes(kRuntimeISA); 224 } else { 225 // If we are going to use implicit stack checks, allocate space for the protected 226 // region at the bottom of the stack. 227 stack_size += Thread::kStackOverflowImplicitCheckSize + 228 GetStackOverflowReservedBytes(kRuntimeISA); 229 } 230 231 // Some systems require the stack size to be a multiple of the system page size, so round up. 232 stack_size = RoundUp(stack_size, kPageSize); 233 234 return stack_size; 235} 236 237// Global variable to prevent the compiler optimizing away the page reads for the stack. 238byte dont_optimize_this; 239 240// Install a protected region in the stack. This is used to trigger a SIGSEGV if a stack 241// overflow is detected. It is located right below the stack_begin_. 242// 243// There is a little complexity here that deserves a special mention. On some 244// architectures, the stack created using a VM_GROWSDOWN flag 245// to prevent memory being allocated when it's not needed. This flag makes the 246// kernel only allocate memory for the stack by growing down in memory. Because we 247// want to put an mprotected region far away from that at the stack top, we need 248// to make sure the pages for the stack are mapped in before we call mprotect. We do 249// this by reading every page from the stack bottom (highest address) to the stack top. 250// We then madvise this away. 251void Thread::InstallImplicitProtection() { 252 byte* pregion = tlsPtr_.stack_begin - kStackOverflowProtectedSize; 253 byte* stack_himem = tlsPtr_.stack_end; 254 byte* stack_top = reinterpret_cast<byte*>(reinterpret_cast<uintptr_t>(&stack_himem) & 255 ~(kPageSize - 1)); // Page containing current top of stack. 256 257 // First remove the protection on the protected region as will want to read and 258 // write it. This may fail (on the first attempt when the stack is not mapped) 259 // but we ignore that. 260 UnprotectStack(); 261 262 // Map in the stack. This must be done by reading from the 263 // current stack pointer downwards as the stack may be mapped using VM_GROWSDOWN 264 // in the kernel. Any access more than a page below the current SP might cause 265 // a segv. 266 267 // Read every page from the high address to the low. 268 for (byte* p = stack_top; p >= pregion; p -= kPageSize) { 269 dont_optimize_this = *p; 270 } 271 272 VLOG(threads) << "installing stack protected region at " << std::hex << 273 static_cast<void*>(pregion) << " to " << 274 static_cast<void*>(pregion + kStackOverflowProtectedSize - 1); 275 276 // Protect the bottom of the stack to prevent read/write to it. 277 ProtectStack(); 278 279 // Tell the kernel that we won't be needing these pages any more. 280 // NB. madvise will probably write zeroes into the memory (on linux it does). 281 uint32_t unwanted_size = stack_top - pregion - kPageSize; 282 madvise(pregion, unwanted_size, MADV_DONTNEED); 283} 284 285void Thread::CreateNativeThread(JNIEnv* env, jobject java_peer, size_t stack_size, bool is_daemon) { 286 CHECK(java_peer != nullptr); 287 Thread* self = static_cast<JNIEnvExt*>(env)->self; 288 Runtime* runtime = Runtime::Current(); 289 290 // Atomically start the birth of the thread ensuring the runtime isn't shutting down. 291 bool thread_start_during_shutdown = false; 292 { 293 MutexLock mu(self, *Locks::runtime_shutdown_lock_); 294 if (runtime->IsShuttingDownLocked()) { 295 thread_start_during_shutdown = true; 296 } else { 297 runtime->StartThreadBirth(); 298 } 299 } 300 if (thread_start_during_shutdown) { 301 ScopedLocalRef<jclass> error_class(env, env->FindClass("java/lang/InternalError")); 302 env->ThrowNew(error_class.get(), "Thread starting during runtime shutdown"); 303 return; 304 } 305 306 Thread* child_thread = new Thread(is_daemon); 307 // Use global JNI ref to hold peer live while child thread starts. 308 child_thread->tlsPtr_.jpeer = env->NewGlobalRef(java_peer); 309 stack_size = FixStackSize(stack_size); 310 311 // Thread.start is synchronized, so we know that nativePeer is 0, and know that we're not racing to 312 // assign it. 313 env->SetLongField(java_peer, WellKnownClasses::java_lang_Thread_nativePeer, 314 reinterpret_cast<jlong>(child_thread)); 315 316 pthread_t new_pthread; 317 pthread_attr_t attr; 318 CHECK_PTHREAD_CALL(pthread_attr_init, (&attr), "new thread"); 319 CHECK_PTHREAD_CALL(pthread_attr_setdetachstate, (&attr, PTHREAD_CREATE_DETACHED), "PTHREAD_CREATE_DETACHED"); 320 CHECK_PTHREAD_CALL(pthread_attr_setstacksize, (&attr, stack_size), stack_size); 321 int pthread_create_result = pthread_create(&new_pthread, &attr, Thread::CreateCallback, child_thread); 322 CHECK_PTHREAD_CALL(pthread_attr_destroy, (&attr), "new thread"); 323 324 if (pthread_create_result != 0) { 325 // pthread_create(3) failed, so clean up. 326 { 327 MutexLock mu(self, *Locks::runtime_shutdown_lock_); 328 runtime->EndThreadBirth(); 329 } 330 // Manually delete the global reference since Thread::Init will not have been run. 331 env->DeleteGlobalRef(child_thread->tlsPtr_.jpeer); 332 child_thread->tlsPtr_.jpeer = nullptr; 333 delete child_thread; 334 child_thread = nullptr; 335 // TODO: remove from thread group? 336 env->SetLongField(java_peer, WellKnownClasses::java_lang_Thread_nativePeer, 0); 337 { 338 std::string msg(StringPrintf("pthread_create (%s stack) failed: %s", 339 PrettySize(stack_size).c_str(), strerror(pthread_create_result))); 340 ScopedObjectAccess soa(env); 341 soa.Self()->ThrowOutOfMemoryError(msg.c_str()); 342 } 343 } 344} 345 346void Thread::Init(ThreadList* thread_list, JavaVMExt* java_vm) { 347 // This function does all the initialization that must be run by the native thread it applies to. 348 // (When we create a new thread from managed code, we allocate the Thread* in Thread::Create so 349 // we can handshake with the corresponding native thread when it's ready.) Check this native 350 // thread hasn't been through here already... 351 CHECK(Thread::Current() == nullptr); 352 SetUpAlternateSignalStack(); 353 InitCpu(); 354 InitTlsEntryPoints(); 355 RemoveSuspendTrigger(); 356 InitCardTable(); 357 InitTid(); 358 // Set pthread_self_ ahead of pthread_setspecific, that makes Thread::Current function, this 359 // avoids pthread_self_ ever being invalid when discovered from Thread::Current(). 360 tlsPtr_.pthread_self = pthread_self(); 361 CHECK(is_started_); 362 CHECK_PTHREAD_CALL(pthread_setspecific, (Thread::pthread_key_self_, this), "attach self"); 363 DCHECK_EQ(Thread::Current(), this); 364 365 tls32_.thin_lock_thread_id = thread_list->AllocThreadId(this); 366 InitStackHwm(); 367 368 tlsPtr_.jni_env = new JNIEnvExt(this, java_vm); 369 thread_list->Register(this); 370} 371 372Thread* Thread::Attach(const char* thread_name, bool as_daemon, jobject thread_group, 373 bool create_peer) { 374 Thread* self; 375 Runtime* runtime = Runtime::Current(); 376 if (runtime == nullptr) { 377 LOG(ERROR) << "Thread attaching to non-existent runtime: " << thread_name; 378 return nullptr; 379 } 380 { 381 MutexLock mu(nullptr, *Locks::runtime_shutdown_lock_); 382 if (runtime->IsShuttingDownLocked()) { 383 LOG(ERROR) << "Thread attaching while runtime is shutting down: " << thread_name; 384 return nullptr; 385 } else { 386 Runtime::Current()->StartThreadBirth(); 387 self = new Thread(as_daemon); 388 self->Init(runtime->GetThreadList(), runtime->GetJavaVM()); 389 Runtime::Current()->EndThreadBirth(); 390 } 391 } 392 393 CHECK_NE(self->GetState(), kRunnable); 394 self->SetState(kNative); 395 396 // If we're the main thread, ClassLinker won't be created until after we're attached, 397 // so that thread needs a two-stage attach. Regular threads don't need this hack. 398 // In the compiler, all threads need this hack, because no-one's going to be getting 399 // a native peer! 400 if (create_peer) { 401 self->CreatePeer(thread_name, as_daemon, thread_group); 402 } else { 403 // These aren't necessary, but they improve diagnostics for unit tests & command-line tools. 404 if (thread_name != nullptr) { 405 self->tlsPtr_.name->assign(thread_name); 406 ::art::SetThreadName(thread_name); 407 } else if (self->GetJniEnv()->check_jni) { 408 LOG(WARNING) << *Thread::Current() << " attached without supplying a name"; 409 } 410 } 411 412 return self; 413} 414 415void Thread::CreatePeer(const char* name, bool as_daemon, jobject thread_group) { 416 Runtime* runtime = Runtime::Current(); 417 CHECK(runtime->IsStarted()); 418 JNIEnv* env = tlsPtr_.jni_env; 419 420 if (thread_group == nullptr) { 421 thread_group = runtime->GetMainThreadGroup(); 422 } 423 ScopedLocalRef<jobject> thread_name(env, env->NewStringUTF(name)); 424 jint thread_priority = GetNativePriority(); 425 jboolean thread_is_daemon = as_daemon; 426 427 ScopedLocalRef<jobject> peer(env, env->AllocObject(WellKnownClasses::java_lang_Thread)); 428 if (peer.get() == nullptr) { 429 CHECK(IsExceptionPending()); 430 return; 431 } 432 { 433 ScopedObjectAccess soa(this); 434 tlsPtr_.opeer = soa.Decode<mirror::Object*>(peer.get()); 435 } 436 env->CallNonvirtualVoidMethod(peer.get(), 437 WellKnownClasses::java_lang_Thread, 438 WellKnownClasses::java_lang_Thread_init, 439 thread_group, thread_name.get(), thread_priority, thread_is_daemon); 440 AssertNoPendingException(); 441 442 Thread* self = this; 443 DCHECK_EQ(self, Thread::Current()); 444 env->SetLongField(peer.get(), WellKnownClasses::java_lang_Thread_nativePeer, 445 reinterpret_cast<jlong>(self)); 446 447 ScopedObjectAccess soa(self); 448 StackHandleScope<1> hs(self); 449 Handle<mirror::String> peer_thread_name(hs.NewHandle(GetThreadName(soa))); 450 if (peer_thread_name.Get() == nullptr) { 451 // The Thread constructor should have set the Thread.name to a 452 // non-null value. However, because we can run without code 453 // available (in the compiler, in tests), we manually assign the 454 // fields the constructor should have set. 455 if (runtime->IsActiveTransaction()) { 456 InitPeer<true>(soa, thread_is_daemon, thread_group, thread_name.get(), thread_priority); 457 } else { 458 InitPeer<false>(soa, thread_is_daemon, thread_group, thread_name.get(), thread_priority); 459 } 460 peer_thread_name.Assign(GetThreadName(soa)); 461 } 462 // 'thread_name' may have been null, so don't trust 'peer_thread_name' to be non-null. 463 if (peer_thread_name.Get() != nullptr) { 464 SetThreadName(peer_thread_name->ToModifiedUtf8().c_str()); 465 } 466} 467 468template<bool kTransactionActive> 469void Thread::InitPeer(ScopedObjectAccess& soa, jboolean thread_is_daemon, jobject thread_group, 470 jobject thread_name, jint thread_priority) { 471 soa.DecodeField(WellKnownClasses::java_lang_Thread_daemon)-> 472 SetBoolean<kTransactionActive>(tlsPtr_.opeer, thread_is_daemon); 473 soa.DecodeField(WellKnownClasses::java_lang_Thread_group)-> 474 SetObject<kTransactionActive>(tlsPtr_.opeer, soa.Decode<mirror::Object*>(thread_group)); 475 soa.DecodeField(WellKnownClasses::java_lang_Thread_name)-> 476 SetObject<kTransactionActive>(tlsPtr_.opeer, soa.Decode<mirror::Object*>(thread_name)); 477 soa.DecodeField(WellKnownClasses::java_lang_Thread_priority)-> 478 SetInt<kTransactionActive>(tlsPtr_.opeer, thread_priority); 479} 480 481void Thread::SetThreadName(const char* name) { 482 tlsPtr_.name->assign(name); 483 ::art::SetThreadName(name); 484 Dbg::DdmSendThreadNotification(this, CHUNK_TYPE("THNM")); 485} 486 487void Thread::InitStackHwm() { 488 void* read_stack_base; 489 size_t read_stack_size; 490 GetThreadStack(tlsPtr_.pthread_self, &read_stack_base, &read_stack_size); 491 492 // TODO: include this in the thread dumps; potentially useful in SIGQUIT output? 493 VLOG(threads) << StringPrintf("Native stack is at %p (%s)", read_stack_base, 494 PrettySize(read_stack_size).c_str()); 495 496 tlsPtr_.stack_begin = reinterpret_cast<byte*>(read_stack_base); 497 tlsPtr_.stack_size = read_stack_size; 498 499 // The minimum stack size we can cope with is the overflow reserved bytes (typically 500 // 8K) + the protected region size (4K) + another page (4K). Typically this will 501 // be 8+4+4 = 16K. The thread won't be able to do much with this stack even the GC takes 502 // between 8K and 12K. 503 uint32_t min_stack = GetStackOverflowReservedBytes(kRuntimeISA) + kStackOverflowProtectedSize 504 + 4 * KB; 505 if (read_stack_size <= min_stack) { 506 LOG(FATAL) << "Attempt to attach a thread with a too-small stack (" << read_stack_size 507 << " bytes)"; 508 } 509 510 // TODO: move this into the Linux GetThreadStack implementation. 511#if !defined(__APPLE__) 512 // If we're the main thread, check whether we were run with an unlimited stack. In that case, 513 // glibc will have reported a 2GB stack for our 32-bit process, and our stack overflow detection 514 // will be broken because we'll die long before we get close to 2GB. 515 bool is_main_thread = (::art::GetTid() == getpid()); 516 if (is_main_thread) { 517 rlimit stack_limit; 518 if (getrlimit(RLIMIT_STACK, &stack_limit) == -1) { 519 PLOG(FATAL) << "getrlimit(RLIMIT_STACK) failed"; 520 } 521 if (stack_limit.rlim_cur == RLIM_INFINITY) { 522 // Find the default stack size for new threads... 523 pthread_attr_t default_attributes; 524 size_t default_stack_size; 525 CHECK_PTHREAD_CALL(pthread_attr_init, (&default_attributes), "default stack size query"); 526 CHECK_PTHREAD_CALL(pthread_attr_getstacksize, (&default_attributes, &default_stack_size), 527 "default stack size query"); 528 CHECK_PTHREAD_CALL(pthread_attr_destroy, (&default_attributes), "default stack size query"); 529 530 // ...and use that as our limit. 531 size_t old_stack_size = read_stack_size; 532 tlsPtr_.stack_size = default_stack_size; 533 tlsPtr_.stack_begin += (old_stack_size - default_stack_size); 534 VLOG(threads) << "Limiting unlimited stack (reported as " << PrettySize(old_stack_size) << ")" 535 << " to " << PrettySize(default_stack_size) 536 << " with base " << reinterpret_cast<void*>(tlsPtr_.stack_begin); 537 } 538 } 539#endif 540 541 // Set stack_end_ to the bottom of the stack saving space of stack overflows 542 bool implicit_stack_check = !Runtime::Current()->ExplicitStackOverflowChecks(); 543 ResetDefaultStackEnd(); 544 545 // Install the protected region if we are doing implicit overflow checks. 546 if (implicit_stack_check) { 547 size_t guardsize; 548 pthread_attr_t attributes; 549 CHECK_PTHREAD_CALL(pthread_attr_init, (&attributes), "guard size query"); 550 CHECK_PTHREAD_CALL(pthread_attr_getguardsize, (&attributes, &guardsize), "guard size query"); 551 CHECK_PTHREAD_CALL(pthread_attr_destroy, (&attributes), "guard size query"); 552 // The thread might have protected region at the bottom. We need 553 // to install our own region so we need to move the limits 554 // of the stack to make room for it. 555 556#if defined(__i386__) || defined(__x86_64__) 557 // Work around issue trying to read last page of stack on Intel. 558 // The bug for this is b/17111575. The problem is that we are 559 // unable to read the page just above the guard page on the 560 // main stack on an intel target. When the bug is fixed 561 // this can be removed. 562 if (::art::GetTid() == getpid()) { 563 guardsize += 4 * KB; 564 } 565#endif 566 tlsPtr_.stack_begin += guardsize + kStackOverflowProtectedSize; 567 tlsPtr_.stack_end += guardsize + kStackOverflowProtectedSize; 568 tlsPtr_.stack_size -= guardsize; 569 570 InstallImplicitProtection(); 571 } 572 573 // Sanity check. 574 int stack_variable; 575 CHECK_GT(&stack_variable, reinterpret_cast<void*>(tlsPtr_.stack_end)); 576} 577 578void Thread::ShortDump(std::ostream& os) const { 579 os << "Thread["; 580 if (GetThreadId() != 0) { 581 // If we're in kStarting, we won't have a thin lock id or tid yet. 582 os << GetThreadId() 583 << ",tid=" << GetTid() << ','; 584 } 585 os << GetState() 586 << ",Thread*=" << this 587 << ",peer=" << tlsPtr_.opeer 588 << ",\"" << *tlsPtr_.name << "\"" 589 << "]"; 590} 591 592void Thread::Dump(std::ostream& os) const { 593 DumpState(os); 594 DumpStack(os); 595} 596 597mirror::String* Thread::GetThreadName(const ScopedObjectAccessAlreadyRunnable& soa) const { 598 mirror::ArtField* f = soa.DecodeField(WellKnownClasses::java_lang_Thread_name); 599 return (tlsPtr_.opeer != nullptr) ? reinterpret_cast<mirror::String*>(f->GetObject(tlsPtr_.opeer)) : nullptr; 600} 601 602void Thread::GetThreadName(std::string& name) const { 603 name.assign(*tlsPtr_.name); 604} 605 606uint64_t Thread::GetCpuMicroTime() const { 607#if defined(HAVE_POSIX_CLOCKS) 608 clockid_t cpu_clock_id; 609 pthread_getcpuclockid(tlsPtr_.pthread_self, &cpu_clock_id); 610 timespec now; 611 clock_gettime(cpu_clock_id, &now); 612 return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000) + now.tv_nsec / UINT64_C(1000); 613#else 614 UNIMPLEMENTED(WARNING); 615 return -1; 616#endif 617} 618 619// Attempt to rectify locks so that we dump thread list with required locks before exiting. 620static void UnsafeLogFatalForSuspendCount(Thread* self, Thread* thread) NO_THREAD_SAFETY_ANALYSIS { 621 LOG(ERROR) << *thread << " suspend count already zero."; 622 Locks::thread_suspend_count_lock_->Unlock(self); 623 if (!Locks::mutator_lock_->IsSharedHeld(self)) { 624 Locks::mutator_lock_->SharedTryLock(self); 625 if (!Locks::mutator_lock_->IsSharedHeld(self)) { 626 LOG(WARNING) << "Dumping thread list without holding mutator_lock_"; 627 } 628 } 629 if (!Locks::thread_list_lock_->IsExclusiveHeld(self)) { 630 Locks::thread_list_lock_->TryLock(self); 631 if (!Locks::thread_list_lock_->IsExclusiveHeld(self)) { 632 LOG(WARNING) << "Dumping thread list without holding thread_list_lock_"; 633 } 634 } 635 std::ostringstream ss; 636 Runtime::Current()->GetThreadList()->DumpLocked(ss); 637 LOG(FATAL) << ss.str(); 638} 639 640void Thread::ModifySuspendCount(Thread* self, int delta, bool for_debugger) { 641 if (kIsDebugBuild) { 642 DCHECK(delta == -1 || delta == +1 || delta == -tls32_.debug_suspend_count) 643 << delta << " " << tls32_.debug_suspend_count << " " << this; 644 DCHECK_GE(tls32_.suspend_count, tls32_.debug_suspend_count) << this; 645 Locks::thread_suspend_count_lock_->AssertHeld(self); 646 if (this != self && !IsSuspended()) { 647 Locks::thread_list_lock_->AssertHeld(self); 648 } 649 } 650 if (UNLIKELY(delta < 0 && tls32_.suspend_count <= 0)) { 651 UnsafeLogFatalForSuspendCount(self, this); 652 return; 653 } 654 655 tls32_.suspend_count += delta; 656 if (for_debugger) { 657 tls32_.debug_suspend_count += delta; 658 } 659 660 if (tls32_.suspend_count == 0) { 661 AtomicClearFlag(kSuspendRequest); 662 } else { 663 AtomicSetFlag(kSuspendRequest); 664 TriggerSuspend(); 665 } 666} 667 668void Thread::RunCheckpointFunction() { 669 Closure *checkpoints[kMaxCheckpoints]; 670 671 // Grab the suspend_count lock and copy the current set of 672 // checkpoints. Then clear the list and the flag. The RequestCheckpoint 673 // function will also grab this lock so we prevent a race between setting 674 // the kCheckpointRequest flag and clearing it. 675 { 676 MutexLock mu(this, *Locks::thread_suspend_count_lock_); 677 for (uint32_t i = 0; i < kMaxCheckpoints; ++i) { 678 checkpoints[i] = tlsPtr_.checkpoint_functions[i]; 679 tlsPtr_.checkpoint_functions[i] = nullptr; 680 } 681 AtomicClearFlag(kCheckpointRequest); 682 } 683 684 // Outside the lock, run all the checkpoint functions that 685 // we collected. 686 bool found_checkpoint = false; 687 for (uint32_t i = 0; i < kMaxCheckpoints; ++i) { 688 if (checkpoints[i] != nullptr) { 689 ATRACE_BEGIN("Checkpoint function"); 690 checkpoints[i]->Run(this); 691 ATRACE_END(); 692 found_checkpoint = true; 693 } 694 } 695 CHECK(found_checkpoint); 696} 697 698bool Thread::RequestCheckpoint(Closure* function) { 699 union StateAndFlags old_state_and_flags; 700 old_state_and_flags.as_int = tls32_.state_and_flags.as_int; 701 if (old_state_and_flags.as_struct.state != kRunnable) { 702 return false; // Fail, thread is suspended and so can't run a checkpoint. 703 } 704 705 uint32_t available_checkpoint = kMaxCheckpoints; 706 for (uint32_t i = 0 ; i < kMaxCheckpoints; ++i) { 707 if (tlsPtr_.checkpoint_functions[i] == nullptr) { 708 available_checkpoint = i; 709 break; 710 } 711 } 712 if (available_checkpoint == kMaxCheckpoints) { 713 // No checkpoint functions available, we can't run a checkpoint 714 return false; 715 } 716 tlsPtr_.checkpoint_functions[available_checkpoint] = function; 717 718 // Checkpoint function installed now install flag bit. 719 // We must be runnable to request a checkpoint. 720 DCHECK_EQ(old_state_and_flags.as_struct.state, kRunnable); 721 union StateAndFlags new_state_and_flags; 722 new_state_and_flags.as_int = old_state_and_flags.as_int; 723 new_state_and_flags.as_struct.flags |= kCheckpointRequest; 724 bool success = 725 tls32_.state_and_flags.as_atomic_int.CompareExchangeStrongSequentiallyConsistent(old_state_and_flags.as_int, 726 new_state_and_flags.as_int); 727 if (UNLIKELY(!success)) { 728 // The thread changed state before the checkpoint was installed. 729 CHECK_EQ(tlsPtr_.checkpoint_functions[available_checkpoint], function); 730 tlsPtr_.checkpoint_functions[available_checkpoint] = nullptr; 731 } else { 732 CHECK_EQ(ReadFlag(kCheckpointRequest), true); 733 TriggerSuspend(); 734 } 735 return success; 736} 737 738void Thread::FullSuspendCheck() { 739 VLOG(threads) << this << " self-suspending"; 740 ATRACE_BEGIN("Full suspend check"); 741 // Make thread appear suspended to other threads, release mutator_lock_. 742 TransitionFromRunnableToSuspended(kSuspended); 743 // Transition back to runnable noting requests to suspend, re-acquire share on mutator_lock_. 744 TransitionFromSuspendedToRunnable(); 745 ATRACE_END(); 746 VLOG(threads) << this << " self-reviving"; 747} 748 749void Thread::DumpState(std::ostream& os, const Thread* thread, pid_t tid) { 750 std::string group_name; 751 int priority; 752 bool is_daemon = false; 753 Thread* self = Thread::Current(); 754 755 // Don't do this if we are aborting since the GC may have all the threads suspended. This will 756 // cause ScopedObjectAccessUnchecked to deadlock. 757 if (gAborting == 0 && self != nullptr && thread != nullptr && thread->tlsPtr_.opeer != nullptr) { 758 ScopedObjectAccessUnchecked soa(self); 759 priority = soa.DecodeField(WellKnownClasses::java_lang_Thread_priority) 760 ->GetInt(thread->tlsPtr_.opeer); 761 is_daemon = soa.DecodeField(WellKnownClasses::java_lang_Thread_daemon) 762 ->GetBoolean(thread->tlsPtr_.opeer); 763 764 mirror::Object* thread_group = 765 soa.DecodeField(WellKnownClasses::java_lang_Thread_group)->GetObject(thread->tlsPtr_.opeer); 766 767 if (thread_group != nullptr) { 768 mirror::ArtField* group_name_field = 769 soa.DecodeField(WellKnownClasses::java_lang_ThreadGroup_name); 770 mirror::String* group_name_string = 771 reinterpret_cast<mirror::String*>(group_name_field->GetObject(thread_group)); 772 group_name = (group_name_string != nullptr) ? group_name_string->ToModifiedUtf8() : "<null>"; 773 } 774 } else { 775 priority = GetNativePriority(); 776 } 777 778 std::string scheduler_group_name(GetSchedulerGroupName(tid)); 779 if (scheduler_group_name.empty()) { 780 scheduler_group_name = "default"; 781 } 782 783 if (thread != nullptr) { 784 os << '"' << *thread->tlsPtr_.name << '"'; 785 if (is_daemon) { 786 os << " daemon"; 787 } 788 os << " prio=" << priority 789 << " tid=" << thread->GetThreadId() 790 << " " << thread->GetState(); 791 if (thread->IsStillStarting()) { 792 os << " (still starting up)"; 793 } 794 os << "\n"; 795 } else { 796 os << '"' << ::art::GetThreadName(tid) << '"' 797 << " prio=" << priority 798 << " (not attached)\n"; 799 } 800 801 if (thread != nullptr) { 802 MutexLock mu(self, *Locks::thread_suspend_count_lock_); 803 os << " | group=\"" << group_name << "\"" 804 << " sCount=" << thread->tls32_.suspend_count 805 << " dsCount=" << thread->tls32_.debug_suspend_count 806 << " obj=" << reinterpret_cast<void*>(thread->tlsPtr_.opeer) 807 << " self=" << reinterpret_cast<const void*>(thread) << "\n"; 808 } 809 810 os << " | sysTid=" << tid 811 << " nice=" << getpriority(PRIO_PROCESS, tid) 812 << " cgrp=" << scheduler_group_name; 813 if (thread != nullptr) { 814 int policy; 815 sched_param sp; 816 CHECK_PTHREAD_CALL(pthread_getschedparam, (thread->tlsPtr_.pthread_self, &policy, &sp), 817 __FUNCTION__); 818 os << " sched=" << policy << "/" << sp.sched_priority 819 << " handle=" << reinterpret_cast<void*>(thread->tlsPtr_.pthread_self); 820 } 821 os << "\n"; 822 823 // Grab the scheduler stats for this thread. 824 std::string scheduler_stats; 825 if (ReadFileToString(StringPrintf("/proc/self/task/%d/schedstat", tid), &scheduler_stats)) { 826 scheduler_stats.resize(scheduler_stats.size() - 1); // Lose the trailing '\n'. 827 } else { 828 scheduler_stats = "0 0 0"; 829 } 830 831 char native_thread_state = '?'; 832 int utime = 0; 833 int stime = 0; 834 int task_cpu = 0; 835 GetTaskStats(tid, &native_thread_state, &utime, &stime, &task_cpu); 836 837 os << " | state=" << native_thread_state 838 << " schedstat=( " << scheduler_stats << " )" 839 << " utm=" << utime 840 << " stm=" << stime 841 << " core=" << task_cpu 842 << " HZ=" << sysconf(_SC_CLK_TCK) << "\n"; 843 if (thread != nullptr) { 844 os << " | stack=" << reinterpret_cast<void*>(thread->tlsPtr_.stack_begin) << "-" 845 << reinterpret_cast<void*>(thread->tlsPtr_.stack_end) << " stackSize=" 846 << PrettySize(thread->tlsPtr_.stack_size) << "\n"; 847 // Dump the held mutexes. 848 os << " | held mutexes="; 849 for (size_t i = 0; i < kLockLevelCount; ++i) { 850 if (i != kMonitorLock) { 851 BaseMutex* mutex = thread->GetHeldMutex(static_cast<LockLevel>(i)); 852 if (mutex != nullptr) { 853 os << " \"" << mutex->GetName() << "\""; 854 if (mutex->IsReaderWriterMutex()) { 855 ReaderWriterMutex* rw_mutex = down_cast<ReaderWriterMutex*>(mutex); 856 if (rw_mutex->GetExclusiveOwnerTid() == static_cast<uint64_t>(tid)) { 857 os << "(exclusive held)"; 858 } else { 859 os << "(shared held)"; 860 } 861 } 862 } 863 } 864 } 865 os << "\n"; 866 } 867} 868 869void Thread::DumpState(std::ostream& os) const { 870 Thread::DumpState(os, this, GetTid()); 871} 872 873struct StackDumpVisitor : public StackVisitor { 874 StackDumpVisitor(std::ostream& os, Thread* thread, Context* context, bool can_allocate) 875 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) 876 : StackVisitor(thread, context), os(os), thread(thread), can_allocate(can_allocate), 877 last_method(nullptr), last_line_number(0), repetition_count(0), frame_count(0) { 878 } 879 880 virtual ~StackDumpVisitor() { 881 if (frame_count == 0) { 882 os << " (no managed stack frames)\n"; 883 } 884 } 885 886 bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 887 mirror::ArtMethod* m = GetMethod(); 888 if (m->IsRuntimeMethod()) { 889 return true; 890 } 891 const int kMaxRepetition = 3; 892 mirror::Class* c = m->GetDeclaringClass(); 893 mirror::DexCache* dex_cache = c->GetDexCache(); 894 int line_number = -1; 895 if (dex_cache != nullptr) { // be tolerant of bad input 896 const DexFile& dex_file = *dex_cache->GetDexFile(); 897 line_number = dex_file.GetLineNumFromPC(m, GetDexPc(false)); 898 } 899 if (line_number == last_line_number && last_method == m) { 900 ++repetition_count; 901 } else { 902 if (repetition_count >= kMaxRepetition) { 903 os << " ... repeated " << (repetition_count - kMaxRepetition) << " times\n"; 904 } 905 repetition_count = 0; 906 last_line_number = line_number; 907 last_method = m; 908 } 909 if (repetition_count < kMaxRepetition) { 910 os << " at " << PrettyMethod(m, false); 911 if (m->IsNative()) { 912 os << "(Native method)"; 913 } else { 914 const char* source_file(m->GetDeclaringClassSourceFile()); 915 os << "(" << (source_file != nullptr ? source_file : "unavailable") 916 << ":" << line_number << ")"; 917 } 918 os << "\n"; 919 if (frame_count == 0) { 920 Monitor::DescribeWait(os, thread); 921 } 922 if (can_allocate) { 923 // Visit locks, but do not abort on errors. This would trigger a nested abort. 924 Monitor::VisitLocks(this, DumpLockedObject, &os, false); 925 } 926 } 927 928 ++frame_count; 929 return true; 930 } 931 932 static void DumpLockedObject(mirror::Object* o, void* context) 933 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 934 std::ostream& os = *reinterpret_cast<std::ostream*>(context); 935 os << " - locked "; 936 if (o == nullptr) { 937 os << "an unknown object"; 938 } else { 939 if ((o->GetLockWord(false).GetState() == LockWord::kThinLocked) && 940 Locks::mutator_lock_->IsExclusiveHeld(Thread::Current())) { 941 // Getting the identity hashcode here would result in lock inflation and suspension of the 942 // current thread, which isn't safe if this is the only runnable thread. 943 os << StringPrintf("<@addr=0x%" PRIxPTR "> (a %s)", reinterpret_cast<intptr_t>(o), 944 PrettyTypeOf(o).c_str()); 945 } else { 946 os << StringPrintf("<0x%08x> (a %s)", o->IdentityHashCode(), PrettyTypeOf(o).c_str()); 947 } 948 } 949 os << "\n"; 950 } 951 952 std::ostream& os; 953 const Thread* thread; 954 const bool can_allocate; 955 mirror::ArtMethod* method; 956 mirror::ArtMethod* last_method; 957 int last_line_number; 958 int repetition_count; 959 int frame_count; 960}; 961 962static bool ShouldShowNativeStack(const Thread* thread) 963 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 964 ThreadState state = thread->GetState(); 965 966 // In native code somewhere in the VM (one of the kWaitingFor* states)? That's interesting. 967 if (state > kWaiting && state < kStarting) { 968 return true; 969 } 970 971 // In an Object.wait variant or Thread.sleep? That's not interesting. 972 if (state == kTimedWaiting || state == kSleeping || state == kWaiting) { 973 return false; 974 } 975 976 // In some other native method? That's interesting. 977 // We don't just check kNative because native methods will be in state kSuspended if they're 978 // calling back into the VM, or kBlocked if they're blocked on a monitor, or one of the 979 // thread-startup states if it's early enough in their life cycle (http://b/7432159). 980 mirror::ArtMethod* current_method = thread->GetCurrentMethod(nullptr); 981 return current_method != nullptr && current_method->IsNative(); 982} 983 984void Thread::DumpJavaStack(std::ostream& os) const { 985 std::unique_ptr<Context> context(Context::Create()); 986 StackDumpVisitor dumper(os, const_cast<Thread*>(this), context.get(), 987 !tls32_.throwing_OutOfMemoryError); 988 dumper.WalkStack(); 989} 990 991void Thread::DumpStack(std::ostream& os) const { 992 // TODO: we call this code when dying but may not have suspended the thread ourself. The 993 // IsSuspended check is therefore racy with the use for dumping (normally we inhibit 994 // the race with the thread_suspend_count_lock_). 995 bool dump_for_abort = (gAborting > 0); 996 bool safe_to_dump = (this == Thread::Current() || IsSuspended()); 997 if (!kIsDebugBuild) { 998 // We always want to dump the stack for an abort, however, there is no point dumping another 999 // thread's stack in debug builds where we'll hit the not suspended check in the stack walk. 1000 safe_to_dump = (safe_to_dump || dump_for_abort); 1001 } 1002 if (safe_to_dump) { 1003 // If we're currently in native code, dump that stack before dumping the managed stack. 1004 if (dump_for_abort || ShouldShowNativeStack(this)) { 1005 DumpKernelStack(os, GetTid(), " kernel: ", false); 1006 DumpNativeStack(os, GetTid(), " native: ", GetCurrentMethod(nullptr)); 1007 } 1008 DumpJavaStack(os); 1009 } else { 1010 os << "Not able to dump stack of thread that isn't suspended"; 1011 } 1012} 1013 1014void Thread::ThreadExitCallback(void* arg) { 1015 Thread* self = reinterpret_cast<Thread*>(arg); 1016 if (self->tls32_.thread_exit_check_count == 0) { 1017 LOG(WARNING) << "Native thread exiting without having called DetachCurrentThread (maybe it's " 1018 "going to use a pthread_key_create destructor?): " << *self; 1019 CHECK(is_started_); 1020 CHECK_PTHREAD_CALL(pthread_setspecific, (Thread::pthread_key_self_, self), "reattach self"); 1021 self->tls32_.thread_exit_check_count = 1; 1022 } else { 1023 LOG(FATAL) << "Native thread exited without calling DetachCurrentThread: " << *self; 1024 } 1025} 1026 1027void Thread::Startup() { 1028 CHECK(!is_started_); 1029 is_started_ = true; 1030 { 1031 // MutexLock to keep annotalysis happy. 1032 // 1033 // Note we use nullptr for the thread because Thread::Current can 1034 // return garbage since (is_started_ == true) and 1035 // Thread::pthread_key_self_ is not yet initialized. 1036 // This was seen on glibc. 1037 MutexLock mu(nullptr, *Locks::thread_suspend_count_lock_); 1038 resume_cond_ = new ConditionVariable("Thread resumption condition variable", 1039 *Locks::thread_suspend_count_lock_); 1040 } 1041 1042 // Allocate a TLS slot. 1043 CHECK_PTHREAD_CALL(pthread_key_create, (&Thread::pthread_key_self_, Thread::ThreadExitCallback), "self key"); 1044 1045 // Double-check the TLS slot allocation. 1046 if (pthread_getspecific(pthread_key_self_) != nullptr) { 1047 LOG(FATAL) << "Newly-created pthread TLS slot is not nullptr"; 1048 } 1049} 1050 1051void Thread::FinishStartup() { 1052 Runtime* runtime = Runtime::Current(); 1053 CHECK(runtime->IsStarted()); 1054 1055 // Finish attaching the main thread. 1056 ScopedObjectAccess soa(Thread::Current()); 1057 Thread::Current()->CreatePeer("main", false, runtime->GetMainThreadGroup()); 1058 1059 Runtime::Current()->GetClassLinker()->RunRootClinits(); 1060} 1061 1062void Thread::Shutdown() { 1063 CHECK(is_started_); 1064 is_started_ = false; 1065 CHECK_PTHREAD_CALL(pthread_key_delete, (Thread::pthread_key_self_), "self key"); 1066 MutexLock mu(Thread::Current(), *Locks::thread_suspend_count_lock_); 1067 if (resume_cond_ != nullptr) { 1068 delete resume_cond_; 1069 resume_cond_ = nullptr; 1070 } 1071} 1072 1073Thread::Thread(bool daemon) : tls32_(daemon), wait_monitor_(nullptr), interrupted_(false) { 1074 wait_mutex_ = new Mutex("a thread wait mutex"); 1075 wait_cond_ = new ConditionVariable("a thread wait condition variable", *wait_mutex_); 1076 tlsPtr_.debug_invoke_req = new DebugInvokeReq; 1077 tlsPtr_.single_step_control = new SingleStepControl; 1078 tlsPtr_.instrumentation_stack = new std::deque<instrumentation::InstrumentationStackFrame>; 1079 tlsPtr_.name = new std::string(kThreadNameDuringStartup); 1080 1081 CHECK_EQ((sizeof(Thread) % 4), 0U) << sizeof(Thread); 1082 tls32_.state_and_flags.as_struct.flags = 0; 1083 tls32_.state_and_flags.as_struct.state = kNative; 1084 memset(&tlsPtr_.held_mutexes[0], 0, sizeof(tlsPtr_.held_mutexes)); 1085 std::fill(tlsPtr_.rosalloc_runs, 1086 tlsPtr_.rosalloc_runs + kNumRosAllocThreadLocalSizeBrackets, 1087 gc::allocator::RosAlloc::GetDedicatedFullRun()); 1088 for (uint32_t i = 0; i < kMaxCheckpoints; ++i) { 1089 tlsPtr_.checkpoint_functions[i] = nullptr; 1090 } 1091} 1092 1093bool Thread::IsStillStarting() const { 1094 // You might think you can check whether the state is kStarting, but for much of thread startup, 1095 // the thread is in kNative; it might also be in kVmWait. 1096 // You might think you can check whether the peer is nullptr, but the peer is actually created and 1097 // assigned fairly early on, and needs to be. 1098 // It turns out that the last thing to change is the thread name; that's a good proxy for "has 1099 // this thread _ever_ entered kRunnable". 1100 return (tlsPtr_.jpeer == nullptr && tlsPtr_.opeer == nullptr) || 1101 (*tlsPtr_.name == kThreadNameDuringStartup); 1102} 1103 1104void Thread::AssertNoPendingException() const { 1105 if (UNLIKELY(IsExceptionPending())) { 1106 ScopedObjectAccess soa(Thread::Current()); 1107 mirror::Throwable* exception = GetException(nullptr); 1108 LOG(FATAL) << "No pending exception expected: " << exception->Dump(); 1109 } 1110} 1111 1112void Thread::AssertNoPendingExceptionForNewException(const char* msg) const { 1113 if (UNLIKELY(IsExceptionPending())) { 1114 ScopedObjectAccess soa(Thread::Current()); 1115 mirror::Throwable* exception = GetException(nullptr); 1116 LOG(FATAL) << "Throwing new exception '" << msg << "' with unexpected pending exception: " 1117 << exception->Dump(); 1118 } 1119} 1120 1121static void MonitorExitVisitor(mirror::Object** object, void* arg, uint32_t /*thread_id*/, 1122 RootType /*root_type*/) 1123 NO_THREAD_SAFETY_ANALYSIS { 1124 Thread* self = reinterpret_cast<Thread*>(arg); 1125 mirror::Object* entered_monitor = *object; 1126 if (self->HoldsLock(entered_monitor)) { 1127 LOG(WARNING) << "Calling MonitorExit on object " 1128 << object << " (" << PrettyTypeOf(entered_monitor) << ")" 1129 << " left locked by native thread " 1130 << *Thread::Current() << " which is detaching"; 1131 entered_monitor->MonitorExit(self); 1132 } 1133} 1134 1135void Thread::Destroy() { 1136 Thread* self = this; 1137 DCHECK_EQ(self, Thread::Current()); 1138 1139 if (tlsPtr_.jni_env != nullptr) { 1140 // On thread detach, all monitors entered with JNI MonitorEnter are automatically exited. 1141 tlsPtr_.jni_env->monitors.VisitRoots(MonitorExitVisitor, self, 0, kRootVMInternal); 1142 // Release locally held global references which releasing may require the mutator lock. 1143 if (tlsPtr_.jpeer != nullptr) { 1144 // If pthread_create fails we don't have a jni env here. 1145 tlsPtr_.jni_env->DeleteGlobalRef(tlsPtr_.jpeer); 1146 tlsPtr_.jpeer = nullptr; 1147 } 1148 if (tlsPtr_.class_loader_override != nullptr) { 1149 tlsPtr_.jni_env->DeleteGlobalRef(tlsPtr_.class_loader_override); 1150 tlsPtr_.class_loader_override = nullptr; 1151 } 1152 } 1153 1154 if (tlsPtr_.opeer != nullptr) { 1155 ScopedObjectAccess soa(self); 1156 // We may need to call user-supplied managed code, do this before final clean-up. 1157 HandleUncaughtExceptions(soa); 1158 RemoveFromThreadGroup(soa); 1159 1160 // this.nativePeer = 0; 1161 if (Runtime::Current()->IsActiveTransaction()) { 1162 soa.DecodeField(WellKnownClasses::java_lang_Thread_nativePeer) 1163 ->SetLong<true>(tlsPtr_.opeer, 0); 1164 } else { 1165 soa.DecodeField(WellKnownClasses::java_lang_Thread_nativePeer) 1166 ->SetLong<false>(tlsPtr_.opeer, 0); 1167 } 1168 Dbg::PostThreadDeath(self); 1169 1170 // Thread.join() is implemented as an Object.wait() on the Thread.lock object. Signal anyone 1171 // who is waiting. 1172 mirror::Object* lock = 1173 soa.DecodeField(WellKnownClasses::java_lang_Thread_lock)->GetObject(tlsPtr_.opeer); 1174 // (This conditional is only needed for tests, where Thread.lock won't have been set.) 1175 if (lock != nullptr) { 1176 StackHandleScope<1> hs(self); 1177 Handle<mirror::Object> h_obj(hs.NewHandle(lock)); 1178 ObjectLock<mirror::Object> locker(self, h_obj); 1179 locker.NotifyAll(); 1180 } 1181 tlsPtr_.opeer = nullptr; 1182 } 1183 1184 Runtime::Current()->GetHeap()->RevokeThreadLocalBuffers(this); 1185} 1186 1187Thread::~Thread() { 1188 CHECK(tlsPtr_.class_loader_override == nullptr); 1189 CHECK(tlsPtr_.jpeer == nullptr); 1190 CHECK(tlsPtr_.opeer == nullptr); 1191 bool initialized = (tlsPtr_.jni_env != nullptr); // Did Thread::Init run? 1192 if (initialized) { 1193 delete tlsPtr_.jni_env; 1194 tlsPtr_.jni_env = nullptr; 1195 } 1196 CHECK_NE(GetState(), kRunnable); 1197 CHECK_NE(ReadFlag(kCheckpointRequest), true); 1198 CHECK(tlsPtr_.checkpoint_functions[0] == nullptr); 1199 CHECK(tlsPtr_.checkpoint_functions[1] == nullptr); 1200 CHECK(tlsPtr_.checkpoint_functions[2] == nullptr); 1201 1202 // We may be deleting a still born thread. 1203 SetStateUnsafe(kTerminated); 1204 1205 delete wait_cond_; 1206 delete wait_mutex_; 1207 1208 if (tlsPtr_.long_jump_context != nullptr) { 1209 delete tlsPtr_.long_jump_context; 1210 } 1211 1212 if (initialized) { 1213 CleanupCpu(); 1214 } 1215 1216 delete tlsPtr_.debug_invoke_req; 1217 delete tlsPtr_.single_step_control; 1218 delete tlsPtr_.instrumentation_stack; 1219 delete tlsPtr_.name; 1220 delete tlsPtr_.stack_trace_sample; 1221 1222 Runtime::Current()->GetHeap()->AssertThreadLocalBuffersAreRevoked(this); 1223 1224 TearDownAlternateSignalStack(); 1225} 1226 1227void Thread::HandleUncaughtExceptions(ScopedObjectAccess& soa) { 1228 if (!IsExceptionPending()) { 1229 return; 1230 } 1231 ScopedLocalRef<jobject> peer(tlsPtr_.jni_env, soa.AddLocalReference<jobject>(tlsPtr_.opeer)); 1232 ScopedThreadStateChange tsc(this, kNative); 1233 1234 // Get and clear the exception. 1235 ScopedLocalRef<jthrowable> exception(tlsPtr_.jni_env, tlsPtr_.jni_env->ExceptionOccurred()); 1236 tlsPtr_.jni_env->ExceptionClear(); 1237 1238 // If the thread has its own handler, use that. 1239 ScopedLocalRef<jobject> handler(tlsPtr_.jni_env, 1240 tlsPtr_.jni_env->GetObjectField(peer.get(), 1241 WellKnownClasses::java_lang_Thread_uncaughtHandler)); 1242 if (handler.get() == nullptr) { 1243 // Otherwise use the thread group's default handler. 1244 handler.reset(tlsPtr_.jni_env->GetObjectField(peer.get(), 1245 WellKnownClasses::java_lang_Thread_group)); 1246 } 1247 1248 // Call the handler. 1249 tlsPtr_.jni_env->CallVoidMethod(handler.get(), 1250 WellKnownClasses::java_lang_Thread$UncaughtExceptionHandler_uncaughtException, 1251 peer.get(), exception.get()); 1252 1253 // If the handler threw, clear that exception too. 1254 tlsPtr_.jni_env->ExceptionClear(); 1255} 1256 1257void Thread::RemoveFromThreadGroup(ScopedObjectAccess& soa) { 1258 // this.group.removeThread(this); 1259 // group can be null if we're in the compiler or a test. 1260 mirror::Object* ogroup = soa.DecodeField(WellKnownClasses::java_lang_Thread_group) 1261 ->GetObject(tlsPtr_.opeer); 1262 if (ogroup != nullptr) { 1263 ScopedLocalRef<jobject> group(soa.Env(), soa.AddLocalReference<jobject>(ogroup)); 1264 ScopedLocalRef<jobject> peer(soa.Env(), soa.AddLocalReference<jobject>(tlsPtr_.opeer)); 1265 ScopedThreadStateChange tsc(soa.Self(), kNative); 1266 tlsPtr_.jni_env->CallVoidMethod(group.get(), 1267 WellKnownClasses::java_lang_ThreadGroup_removeThread, 1268 peer.get()); 1269 } 1270} 1271 1272size_t Thread::NumHandleReferences() { 1273 size_t count = 0; 1274 for (HandleScope* cur = tlsPtr_.top_handle_scope; cur; cur = cur->GetLink()) { 1275 count += cur->NumberOfReferences(); 1276 } 1277 return count; 1278} 1279 1280bool Thread::HandleScopeContains(jobject obj) const { 1281 StackReference<mirror::Object>* hs_entry = 1282 reinterpret_cast<StackReference<mirror::Object>*>(obj); 1283 for (HandleScope* cur = tlsPtr_.top_handle_scope; cur; cur = cur->GetLink()) { 1284 if (cur->Contains(hs_entry)) { 1285 return true; 1286 } 1287 } 1288 // JNI code invoked from portable code uses shadow frames rather than the handle scope. 1289 return tlsPtr_.managed_stack.ShadowFramesContain(hs_entry); 1290} 1291 1292void Thread::HandleScopeVisitRoots(RootCallback* visitor, void* arg, uint32_t thread_id) { 1293 for (HandleScope* cur = tlsPtr_.top_handle_scope; cur; cur = cur->GetLink()) { 1294 size_t num_refs = cur->NumberOfReferences(); 1295 for (size_t j = 0; j < num_refs; ++j) { 1296 mirror::Object* object = cur->GetReference(j); 1297 if (object != nullptr) { 1298 mirror::Object* old_obj = object; 1299 visitor(&object, arg, thread_id, kRootNativeStack); 1300 if (old_obj != object) { 1301 cur->SetReference(j, object); 1302 } 1303 } 1304 } 1305 } 1306} 1307 1308mirror::Object* Thread::DecodeJObject(jobject obj) const { 1309 Locks::mutator_lock_->AssertSharedHeld(this); 1310 if (obj == nullptr) { 1311 return nullptr; 1312 } 1313 IndirectRef ref = reinterpret_cast<IndirectRef>(obj); 1314 IndirectRefKind kind = GetIndirectRefKind(ref); 1315 mirror::Object* result; 1316 // The "kinds" below are sorted by the frequency we expect to encounter them. 1317 if (kind == kLocal) { 1318 IndirectReferenceTable& locals = tlsPtr_.jni_env->locals; 1319 // Local references do not need a read barrier. 1320 result = locals.Get<kWithoutReadBarrier>(ref); 1321 } else if (kind == kHandleScopeOrInvalid) { 1322 // TODO: make stack indirect reference table lookup more efficient. 1323 // Check if this is a local reference in the handle scope. 1324 if (LIKELY(HandleScopeContains(obj))) { 1325 // Read from handle scope. 1326 result = reinterpret_cast<StackReference<mirror::Object>*>(obj)->AsMirrorPtr(); 1327 VerifyObject(result); 1328 } else { 1329 result = kInvalidIndirectRefObject; 1330 } 1331 } else if (kind == kGlobal) { 1332 result = tlsPtr_.jni_env->vm->DecodeGlobal(const_cast<Thread*>(this), ref); 1333 } else { 1334 DCHECK_EQ(kind, kWeakGlobal); 1335 result = tlsPtr_.jni_env->vm->DecodeWeakGlobal(const_cast<Thread*>(this), ref); 1336 if (result == kClearedJniWeakGlobal) { 1337 // This is a special case where it's okay to return nullptr. 1338 return nullptr; 1339 } 1340 } 1341 1342 if (UNLIKELY(result == nullptr)) { 1343 tlsPtr_.jni_env->vm->JniAbortF(nullptr, "use of deleted %s %p", 1344 ToStr<IndirectRefKind>(kind).c_str(), obj); 1345 } 1346 return result; 1347} 1348 1349// Implements java.lang.Thread.interrupted. 1350bool Thread::Interrupted() { 1351 MutexLock mu(Thread::Current(), *wait_mutex_); 1352 bool interrupted = IsInterruptedLocked(); 1353 SetInterruptedLocked(false); 1354 return interrupted; 1355} 1356 1357// Implements java.lang.Thread.isInterrupted. 1358bool Thread::IsInterrupted() { 1359 MutexLock mu(Thread::Current(), *wait_mutex_); 1360 return IsInterruptedLocked(); 1361} 1362 1363void Thread::Interrupt(Thread* self) { 1364 MutexLock mu(self, *wait_mutex_); 1365 if (interrupted_) { 1366 return; 1367 } 1368 interrupted_ = true; 1369 NotifyLocked(self); 1370} 1371 1372void Thread::Notify() { 1373 Thread* self = Thread::Current(); 1374 MutexLock mu(self, *wait_mutex_); 1375 NotifyLocked(self); 1376} 1377 1378void Thread::NotifyLocked(Thread* self) { 1379 if (wait_monitor_ != nullptr) { 1380 wait_cond_->Signal(self); 1381 } 1382} 1383 1384void Thread::SetClassLoaderOverride(jobject class_loader_override) { 1385 if (tlsPtr_.class_loader_override != nullptr) { 1386 GetJniEnv()->DeleteGlobalRef(tlsPtr_.class_loader_override); 1387 } 1388 tlsPtr_.class_loader_override = GetJniEnv()->NewGlobalRef(class_loader_override); 1389} 1390 1391class CountStackDepthVisitor : public StackVisitor { 1392 public: 1393 explicit CountStackDepthVisitor(Thread* thread) 1394 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) 1395 : StackVisitor(thread, nullptr), 1396 depth_(0), skip_depth_(0), skipping_(true) {} 1397 1398 bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1399 // We want to skip frames up to and including the exception's constructor. 1400 // Note we also skip the frame if it doesn't have a method (namely the callee 1401 // save frame) 1402 mirror::ArtMethod* m = GetMethod(); 1403 if (skipping_ && !m->IsRuntimeMethod() && 1404 !mirror::Throwable::GetJavaLangThrowable()->IsAssignableFrom(m->GetDeclaringClass())) { 1405 skipping_ = false; 1406 } 1407 if (!skipping_) { 1408 if (!m->IsRuntimeMethod()) { // Ignore runtime frames (in particular callee save). 1409 ++depth_; 1410 } 1411 } else { 1412 ++skip_depth_; 1413 } 1414 return true; 1415 } 1416 1417 int GetDepth() const { 1418 return depth_; 1419 } 1420 1421 int GetSkipDepth() const { 1422 return skip_depth_; 1423 } 1424 1425 private: 1426 uint32_t depth_; 1427 uint32_t skip_depth_; 1428 bool skipping_; 1429}; 1430 1431template<bool kTransactionActive> 1432class BuildInternalStackTraceVisitor : public StackVisitor { 1433 public: 1434 explicit BuildInternalStackTraceVisitor(Thread* self, Thread* thread, int skip_depth) 1435 : StackVisitor(thread, nullptr), self_(self), 1436 skip_depth_(skip_depth), count_(0), dex_pc_trace_(nullptr), method_trace_(nullptr) {} 1437 1438 bool Init(int depth) 1439 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1440 // Allocate method trace with an extra slot that will hold the PC trace 1441 StackHandleScope<1> hs(self_); 1442 ClassLinker* class_linker = Runtime::Current()->GetClassLinker(); 1443 Handle<mirror::ObjectArray<mirror::Object>> method_trace( 1444 hs.NewHandle(class_linker->AllocObjectArray<mirror::Object>(self_, depth + 1))); 1445 if (method_trace.Get() == nullptr) { 1446 return false; 1447 } 1448 mirror::IntArray* dex_pc_trace = mirror::IntArray::Alloc(self_, depth); 1449 if (dex_pc_trace == nullptr) { 1450 return false; 1451 } 1452 // Save PC trace in last element of method trace, also places it into the 1453 // object graph. 1454 // We are called from native: use non-transactional mode. 1455 method_trace->Set<kTransactionActive>(depth, dex_pc_trace); 1456 // Set the Object*s and assert that no thread suspension is now possible. 1457 const char* last_no_suspend_cause = 1458 self_->StartAssertNoThreadSuspension("Building internal stack trace"); 1459 CHECK(last_no_suspend_cause == nullptr) << last_no_suspend_cause; 1460 method_trace_ = method_trace.Get(); 1461 dex_pc_trace_ = dex_pc_trace; 1462 return true; 1463 } 1464 1465 virtual ~BuildInternalStackTraceVisitor() { 1466 if (method_trace_ != nullptr) { 1467 self_->EndAssertNoThreadSuspension(nullptr); 1468 } 1469 } 1470 1471 bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1472 if (method_trace_ == nullptr || dex_pc_trace_ == nullptr) { 1473 return true; // We're probably trying to fillInStackTrace for an OutOfMemoryError. 1474 } 1475 if (skip_depth_ > 0) { 1476 skip_depth_--; 1477 return true; 1478 } 1479 mirror::ArtMethod* m = GetMethod(); 1480 if (m->IsRuntimeMethod()) { 1481 return true; // Ignore runtime frames (in particular callee save). 1482 } 1483 method_trace_->Set<kTransactionActive>(count_, m); 1484 dex_pc_trace_->Set<kTransactionActive>(count_, 1485 m->IsProxyMethod() ? DexFile::kDexNoIndex : GetDexPc()); 1486 ++count_; 1487 return true; 1488 } 1489 1490 mirror::ObjectArray<mirror::Object>* GetInternalStackTrace() const { 1491 return method_trace_; 1492 } 1493 1494 private: 1495 Thread* const self_; 1496 // How many more frames to skip. 1497 int32_t skip_depth_; 1498 // Current position down stack trace. 1499 uint32_t count_; 1500 // Array of dex PC values. 1501 mirror::IntArray* dex_pc_trace_; 1502 // An array of the methods on the stack, the last entry is a reference to the PC trace. 1503 mirror::ObjectArray<mirror::Object>* method_trace_; 1504}; 1505 1506template<bool kTransactionActive> 1507jobject Thread::CreateInternalStackTrace(const ScopedObjectAccessAlreadyRunnable& soa) const { 1508 // Compute depth of stack 1509 CountStackDepthVisitor count_visitor(const_cast<Thread*>(this)); 1510 count_visitor.WalkStack(); 1511 int32_t depth = count_visitor.GetDepth(); 1512 int32_t skip_depth = count_visitor.GetSkipDepth(); 1513 1514 // Build internal stack trace. 1515 BuildInternalStackTraceVisitor<kTransactionActive> build_trace_visitor(soa.Self(), 1516 const_cast<Thread*>(this), 1517 skip_depth); 1518 if (!build_trace_visitor.Init(depth)) { 1519 return nullptr; // Allocation failed. 1520 } 1521 build_trace_visitor.WalkStack(); 1522 mirror::ObjectArray<mirror::Object>* trace = build_trace_visitor.GetInternalStackTrace(); 1523 if (kIsDebugBuild) { 1524 for (int32_t i = 0; i < trace->GetLength(); ++i) { 1525 CHECK(trace->Get(i) != nullptr); 1526 } 1527 } 1528 return soa.AddLocalReference<jobjectArray>(trace); 1529} 1530template jobject Thread::CreateInternalStackTrace<false>( 1531 const ScopedObjectAccessAlreadyRunnable& soa) const; 1532template jobject Thread::CreateInternalStackTrace<true>( 1533 const ScopedObjectAccessAlreadyRunnable& soa) const; 1534 1535jobjectArray Thread::InternalStackTraceToStackTraceElementArray( 1536 const ScopedObjectAccessAlreadyRunnable& soa, jobject internal, jobjectArray output_array, 1537 int* stack_depth) { 1538 // Decode the internal stack trace into the depth, method trace and PC trace 1539 int32_t depth = soa.Decode<mirror::ObjectArray<mirror::Object>*>(internal)->GetLength() - 1; 1540 1541 ClassLinker* class_linker = Runtime::Current()->GetClassLinker(); 1542 1543 jobjectArray result; 1544 1545 if (output_array != nullptr) { 1546 // Reuse the array we were given. 1547 result = output_array; 1548 // ...adjusting the number of frames we'll write to not exceed the array length. 1549 const int32_t traces_length = 1550 soa.Decode<mirror::ObjectArray<mirror::StackTraceElement>*>(result)->GetLength(); 1551 depth = std::min(depth, traces_length); 1552 } else { 1553 // Create java_trace array and place in local reference table 1554 mirror::ObjectArray<mirror::StackTraceElement>* java_traces = 1555 class_linker->AllocStackTraceElementArray(soa.Self(), depth); 1556 if (java_traces == nullptr) { 1557 return nullptr; 1558 } 1559 result = soa.AddLocalReference<jobjectArray>(java_traces); 1560 } 1561 1562 if (stack_depth != nullptr) { 1563 *stack_depth = depth; 1564 } 1565 1566 for (int32_t i = 0; i < depth; ++i) { 1567 mirror::ObjectArray<mirror::Object>* method_trace = 1568 soa.Decode<mirror::ObjectArray<mirror::Object>*>(internal); 1569 // Prepare parameters for StackTraceElement(String cls, String method, String file, int line) 1570 mirror::ArtMethod* method = down_cast<mirror::ArtMethod*>(method_trace->Get(i)); 1571 int32_t line_number; 1572 StackHandleScope<3> hs(soa.Self()); 1573 auto class_name_object(hs.NewHandle<mirror::String>(nullptr)); 1574 auto source_name_object(hs.NewHandle<mirror::String>(nullptr)); 1575 if (method->IsProxyMethod()) { 1576 line_number = -1; 1577 class_name_object.Assign(method->GetDeclaringClass()->GetName()); 1578 // source_name_object intentionally left null for proxy methods 1579 } else { 1580 mirror::IntArray* pc_trace = down_cast<mirror::IntArray*>(method_trace->Get(depth)); 1581 uint32_t dex_pc = pc_trace->Get(i); 1582 line_number = method->GetLineNumFromDexPC(dex_pc); 1583 // Allocate element, potentially triggering GC 1584 // TODO: reuse class_name_object via Class::name_? 1585 const char* descriptor = method->GetDeclaringClassDescriptor(); 1586 CHECK(descriptor != nullptr); 1587 std::string class_name(PrettyDescriptor(descriptor)); 1588 class_name_object.Assign(mirror::String::AllocFromModifiedUtf8(soa.Self(), class_name.c_str())); 1589 if (class_name_object.Get() == nullptr) { 1590 return nullptr; 1591 } 1592 const char* source_file = method->GetDeclaringClassSourceFile(); 1593 if (source_file != nullptr) { 1594 source_name_object.Assign(mirror::String::AllocFromModifiedUtf8(soa.Self(), source_file)); 1595 if (source_name_object.Get() == nullptr) { 1596 return nullptr; 1597 } 1598 } 1599 } 1600 const char* method_name = method->GetName(); 1601 CHECK(method_name != nullptr); 1602 Handle<mirror::String> method_name_object( 1603 hs.NewHandle(mirror::String::AllocFromModifiedUtf8(soa.Self(), method_name))); 1604 if (method_name_object.Get() == nullptr) { 1605 return nullptr; 1606 } 1607 mirror::StackTraceElement* obj = mirror::StackTraceElement::Alloc( 1608 soa.Self(), class_name_object, method_name_object, source_name_object, line_number); 1609 if (obj == nullptr) { 1610 return nullptr; 1611 } 1612 // We are called from native: use non-transactional mode. 1613 soa.Decode<mirror::ObjectArray<mirror::StackTraceElement>*>(result)->Set<false>(i, obj); 1614 } 1615 return result; 1616} 1617 1618void Thread::ThrowNewExceptionF(const ThrowLocation& throw_location, 1619 const char* exception_class_descriptor, const char* fmt, ...) { 1620 va_list args; 1621 va_start(args, fmt); 1622 ThrowNewExceptionV(throw_location, exception_class_descriptor, 1623 fmt, args); 1624 va_end(args); 1625} 1626 1627void Thread::ThrowNewExceptionV(const ThrowLocation& throw_location, 1628 const char* exception_class_descriptor, 1629 const char* fmt, va_list ap) { 1630 std::string msg; 1631 StringAppendV(&msg, fmt, ap); 1632 ThrowNewException(throw_location, exception_class_descriptor, msg.c_str()); 1633} 1634 1635void Thread::ThrowNewException(const ThrowLocation& throw_location, const char* exception_class_descriptor, 1636 const char* msg) { 1637 // Callers should either clear or call ThrowNewWrappedException. 1638 AssertNoPendingExceptionForNewException(msg); 1639 ThrowNewWrappedException(throw_location, exception_class_descriptor, msg); 1640} 1641 1642void Thread::ThrowNewWrappedException(const ThrowLocation& throw_location, 1643 const char* exception_class_descriptor, 1644 const char* msg) { 1645 DCHECK_EQ(this, Thread::Current()); 1646 ScopedObjectAccessUnchecked soa(this); 1647 StackHandleScope<5> hs(soa.Self()); 1648 // Ensure we don't forget arguments over object allocation. 1649 Handle<mirror::Object> saved_throw_this(hs.NewHandle(throw_location.GetThis())); 1650 Handle<mirror::ArtMethod> saved_throw_method(hs.NewHandle(throw_location.GetMethod())); 1651 // Ignore the cause throw location. TODO: should we report this as a re-throw? 1652 ScopedLocalRef<jobject> cause(GetJniEnv(), soa.AddLocalReference<jobject>(GetException(nullptr))); 1653 bool is_exception_reported = IsExceptionReportedToInstrumentation(); 1654 ClearException(); 1655 Runtime* runtime = Runtime::Current(); 1656 1657 mirror::ClassLoader* cl = nullptr; 1658 if (saved_throw_method.Get() != nullptr) { 1659 cl = saved_throw_method.Get()->GetDeclaringClass()->GetClassLoader(); 1660 } 1661 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(cl)); 1662 Handle<mirror::Class> exception_class( 1663 hs.NewHandle(runtime->GetClassLinker()->FindClass(this, exception_class_descriptor, 1664 class_loader))); 1665 if (UNLIKELY(exception_class.Get() == nullptr)) { 1666 CHECK(IsExceptionPending()); 1667 LOG(ERROR) << "No exception class " << PrettyDescriptor(exception_class_descriptor); 1668 return; 1669 } 1670 1671 if (UNLIKELY(!runtime->GetClassLinker()->EnsureInitialized(exception_class, true, true))) { 1672 DCHECK(IsExceptionPending()); 1673 return; 1674 } 1675 DCHECK(!runtime->IsStarted() || exception_class->IsThrowableClass()); 1676 Handle<mirror::Throwable> exception( 1677 hs.NewHandle(down_cast<mirror::Throwable*>(exception_class->AllocObject(this)))); 1678 1679 // If we couldn't allocate the exception, throw the pre-allocated out of memory exception. 1680 if (exception.Get() == nullptr) { 1681 ThrowLocation gc_safe_throw_location(saved_throw_this.Get(), saved_throw_method.Get(), 1682 throw_location.GetDexPc()); 1683 SetException(gc_safe_throw_location, Runtime::Current()->GetPreAllocatedOutOfMemoryError()); 1684 SetExceptionReportedToInstrumentation(is_exception_reported); 1685 return; 1686 } 1687 1688 // Choose an appropriate constructor and set up the arguments. 1689 const char* signature; 1690 ScopedLocalRef<jstring> msg_string(GetJniEnv(), nullptr); 1691 if (msg != nullptr) { 1692 // Ensure we remember this and the method over the String allocation. 1693 msg_string.reset( 1694 soa.AddLocalReference<jstring>(mirror::String::AllocFromModifiedUtf8(this, msg))); 1695 if (UNLIKELY(msg_string.get() == nullptr)) { 1696 CHECK(IsExceptionPending()); // OOME. 1697 return; 1698 } 1699 if (cause.get() == nullptr) { 1700 signature = "(Ljava/lang/String;)V"; 1701 } else { 1702 signature = "(Ljava/lang/String;Ljava/lang/Throwable;)V"; 1703 } 1704 } else { 1705 if (cause.get() == nullptr) { 1706 signature = "()V"; 1707 } else { 1708 signature = "(Ljava/lang/Throwable;)V"; 1709 } 1710 } 1711 mirror::ArtMethod* exception_init_method = 1712 exception_class->FindDeclaredDirectMethod("<init>", signature); 1713 1714 CHECK(exception_init_method != nullptr) << "No <init>" << signature << " in " 1715 << PrettyDescriptor(exception_class_descriptor); 1716 1717 if (UNLIKELY(!runtime->IsStarted())) { 1718 // Something is trying to throw an exception without a started runtime, which is the common 1719 // case in the compiler. We won't be able to invoke the constructor of the exception, so set 1720 // the exception fields directly. 1721 if (msg != nullptr) { 1722 exception->SetDetailMessage(down_cast<mirror::String*>(DecodeJObject(msg_string.get()))); 1723 } 1724 if (cause.get() != nullptr) { 1725 exception->SetCause(down_cast<mirror::Throwable*>(DecodeJObject(cause.get()))); 1726 } 1727 ScopedLocalRef<jobject> trace(GetJniEnv(), 1728 Runtime::Current()->IsActiveTransaction() 1729 ? CreateInternalStackTrace<true>(soa) 1730 : CreateInternalStackTrace<false>(soa)); 1731 if (trace.get() != nullptr) { 1732 exception->SetStackState(down_cast<mirror::Throwable*>(DecodeJObject(trace.get()))); 1733 } 1734 ThrowLocation gc_safe_throw_location(saved_throw_this.Get(), saved_throw_method.Get(), 1735 throw_location.GetDexPc()); 1736 SetException(gc_safe_throw_location, exception.Get()); 1737 SetExceptionReportedToInstrumentation(is_exception_reported); 1738 } else { 1739 jvalue jv_args[2]; 1740 size_t i = 0; 1741 1742 if (msg != nullptr) { 1743 jv_args[i].l = msg_string.get(); 1744 ++i; 1745 } 1746 if (cause.get() != nullptr) { 1747 jv_args[i].l = cause.get(); 1748 ++i; 1749 } 1750 InvokeWithJValues(soa, exception.Get(), soa.EncodeMethod(exception_init_method), jv_args); 1751 if (LIKELY(!IsExceptionPending())) { 1752 ThrowLocation gc_safe_throw_location(saved_throw_this.Get(), saved_throw_method.Get(), 1753 throw_location.GetDexPc()); 1754 SetException(gc_safe_throw_location, exception.Get()); 1755 SetExceptionReportedToInstrumentation(is_exception_reported); 1756 } 1757 } 1758} 1759 1760void Thread::ThrowOutOfMemoryError(const char* msg) { 1761 LOG(ERROR) << StringPrintf("Throwing OutOfMemoryError \"%s\"%s", 1762 msg, (tls32_.throwing_OutOfMemoryError ? " (recursive case)" : "")); 1763 ThrowLocation throw_location = GetCurrentLocationForThrow(); 1764 if (!tls32_.throwing_OutOfMemoryError) { 1765 tls32_.throwing_OutOfMemoryError = true; 1766 ThrowNewException(throw_location, "Ljava/lang/OutOfMemoryError;", msg); 1767 tls32_.throwing_OutOfMemoryError = false; 1768 } else { 1769 Dump(LOG(ERROR)); // The pre-allocated OOME has no stack, so help out and log one. 1770 SetException(throw_location, Runtime::Current()->GetPreAllocatedOutOfMemoryError()); 1771 } 1772} 1773 1774Thread* Thread::CurrentFromGdb() { 1775 return Thread::Current(); 1776} 1777 1778void Thread::DumpFromGdb() const { 1779 std::ostringstream ss; 1780 Dump(ss); 1781 std::string str(ss.str()); 1782 // log to stderr for debugging command line processes 1783 std::cerr << str; 1784#ifdef HAVE_ANDROID_OS 1785 // log to logcat for debugging frameworks processes 1786 LOG(INFO) << str; 1787#endif 1788} 1789 1790// Explicitly instantiate 32 and 64bit thread offset dumping support. 1791template void Thread::DumpThreadOffset<4>(std::ostream& os, uint32_t offset); 1792template void Thread::DumpThreadOffset<8>(std::ostream& os, uint32_t offset); 1793 1794template<size_t ptr_size> 1795void Thread::DumpThreadOffset(std::ostream& os, uint32_t offset) { 1796#define DO_THREAD_OFFSET(x, y) \ 1797 if (offset == x.Uint32Value()) { \ 1798 os << y; \ 1799 return; \ 1800 } 1801 DO_THREAD_OFFSET(ThreadFlagsOffset<ptr_size>(), "state_and_flags") 1802 DO_THREAD_OFFSET(CardTableOffset<ptr_size>(), "card_table") 1803 DO_THREAD_OFFSET(ExceptionOffset<ptr_size>(), "exception") 1804 DO_THREAD_OFFSET(PeerOffset<ptr_size>(), "peer"); 1805 DO_THREAD_OFFSET(JniEnvOffset<ptr_size>(), "jni_env") 1806 DO_THREAD_OFFSET(SelfOffset<ptr_size>(), "self") 1807 DO_THREAD_OFFSET(StackEndOffset<ptr_size>(), "stack_end") 1808 DO_THREAD_OFFSET(ThinLockIdOffset<ptr_size>(), "thin_lock_thread_id") 1809 DO_THREAD_OFFSET(TopOfManagedStackOffset<ptr_size>(), "top_quick_frame_method") 1810 DO_THREAD_OFFSET(TopOfManagedStackPcOffset<ptr_size>(), "top_quick_frame_pc") 1811 DO_THREAD_OFFSET(TopShadowFrameOffset<ptr_size>(), "top_shadow_frame") 1812 DO_THREAD_OFFSET(TopHandleScopeOffset<ptr_size>(), "top_handle_scope") 1813 DO_THREAD_OFFSET(ThreadSuspendTriggerOffset<ptr_size>(), "suspend_trigger") 1814#undef DO_THREAD_OFFSET 1815 1816#define INTERPRETER_ENTRY_POINT_INFO(x) \ 1817 if (INTERPRETER_ENTRYPOINT_OFFSET(ptr_size, x).Uint32Value() == offset) { \ 1818 os << #x; \ 1819 return; \ 1820 } 1821 INTERPRETER_ENTRY_POINT_INFO(pInterpreterToInterpreterBridge) 1822 INTERPRETER_ENTRY_POINT_INFO(pInterpreterToCompiledCodeBridge) 1823#undef INTERPRETER_ENTRY_POINT_INFO 1824 1825#define JNI_ENTRY_POINT_INFO(x) \ 1826 if (JNI_ENTRYPOINT_OFFSET(ptr_size, x).Uint32Value() == offset) { \ 1827 os << #x; \ 1828 return; \ 1829 } 1830 JNI_ENTRY_POINT_INFO(pDlsymLookup) 1831#undef JNI_ENTRY_POINT_INFO 1832 1833#define PORTABLE_ENTRY_POINT_INFO(x) \ 1834 if (PORTABLE_ENTRYPOINT_OFFSET(ptr_size, x).Uint32Value() == offset) { \ 1835 os << #x; \ 1836 return; \ 1837 } 1838 PORTABLE_ENTRY_POINT_INFO(pPortableImtConflictTrampoline) 1839 PORTABLE_ENTRY_POINT_INFO(pPortableResolutionTrampoline) 1840 PORTABLE_ENTRY_POINT_INFO(pPortableToInterpreterBridge) 1841#undef PORTABLE_ENTRY_POINT_INFO 1842 1843#define QUICK_ENTRY_POINT_INFO(x) \ 1844 if (QUICK_ENTRYPOINT_OFFSET(ptr_size, x).Uint32Value() == offset) { \ 1845 os << #x; \ 1846 return; \ 1847 } 1848 QUICK_ENTRY_POINT_INFO(pAllocArray) 1849 QUICK_ENTRY_POINT_INFO(pAllocArrayResolved) 1850 QUICK_ENTRY_POINT_INFO(pAllocArrayWithAccessCheck) 1851 QUICK_ENTRY_POINT_INFO(pAllocObject) 1852 QUICK_ENTRY_POINT_INFO(pAllocObjectResolved) 1853 QUICK_ENTRY_POINT_INFO(pAllocObjectInitialized) 1854 QUICK_ENTRY_POINT_INFO(pAllocObjectWithAccessCheck) 1855 QUICK_ENTRY_POINT_INFO(pCheckAndAllocArray) 1856 QUICK_ENTRY_POINT_INFO(pCheckAndAllocArrayWithAccessCheck) 1857 QUICK_ENTRY_POINT_INFO(pInstanceofNonTrivial) 1858 QUICK_ENTRY_POINT_INFO(pCheckCast) 1859 QUICK_ENTRY_POINT_INFO(pInitializeStaticStorage) 1860 QUICK_ENTRY_POINT_INFO(pInitializeTypeAndVerifyAccess) 1861 QUICK_ENTRY_POINT_INFO(pInitializeType) 1862 QUICK_ENTRY_POINT_INFO(pResolveString) 1863 QUICK_ENTRY_POINT_INFO(pSet8Instance) 1864 QUICK_ENTRY_POINT_INFO(pSet8Static) 1865 QUICK_ENTRY_POINT_INFO(pSet16Instance) 1866 QUICK_ENTRY_POINT_INFO(pSet16Static) 1867 QUICK_ENTRY_POINT_INFO(pSet32Instance) 1868 QUICK_ENTRY_POINT_INFO(pSet32Static) 1869 QUICK_ENTRY_POINT_INFO(pSet64Instance) 1870 QUICK_ENTRY_POINT_INFO(pSet64Static) 1871 QUICK_ENTRY_POINT_INFO(pSetObjInstance) 1872 QUICK_ENTRY_POINT_INFO(pSetObjStatic) 1873 QUICK_ENTRY_POINT_INFO(pGetByteInstance) 1874 QUICK_ENTRY_POINT_INFO(pGetBooleanInstance) 1875 QUICK_ENTRY_POINT_INFO(pGetByteStatic) 1876 QUICK_ENTRY_POINT_INFO(pGetBooleanStatic) 1877 QUICK_ENTRY_POINT_INFO(pGetShortInstance) 1878 QUICK_ENTRY_POINT_INFO(pGetCharInstance) 1879 QUICK_ENTRY_POINT_INFO(pGetShortStatic) 1880 QUICK_ENTRY_POINT_INFO(pGetCharStatic) 1881 QUICK_ENTRY_POINT_INFO(pGet32Instance) 1882 QUICK_ENTRY_POINT_INFO(pGet32Static) 1883 QUICK_ENTRY_POINT_INFO(pGet64Instance) 1884 QUICK_ENTRY_POINT_INFO(pGet64Static) 1885 QUICK_ENTRY_POINT_INFO(pGetObjInstance) 1886 QUICK_ENTRY_POINT_INFO(pGetObjStatic) 1887 QUICK_ENTRY_POINT_INFO(pAputObjectWithNullAndBoundCheck) 1888 QUICK_ENTRY_POINT_INFO(pAputObjectWithBoundCheck) 1889 QUICK_ENTRY_POINT_INFO(pAputObject) 1890 QUICK_ENTRY_POINT_INFO(pHandleFillArrayData) 1891 QUICK_ENTRY_POINT_INFO(pJniMethodStart) 1892 QUICK_ENTRY_POINT_INFO(pJniMethodStartSynchronized) 1893 QUICK_ENTRY_POINT_INFO(pJniMethodEnd) 1894 QUICK_ENTRY_POINT_INFO(pJniMethodEndSynchronized) 1895 QUICK_ENTRY_POINT_INFO(pJniMethodEndWithReference) 1896 QUICK_ENTRY_POINT_INFO(pJniMethodEndWithReferenceSynchronized) 1897 QUICK_ENTRY_POINT_INFO(pQuickGenericJniTrampoline) 1898 QUICK_ENTRY_POINT_INFO(pLockObject) 1899 QUICK_ENTRY_POINT_INFO(pUnlockObject) 1900 QUICK_ENTRY_POINT_INFO(pCmpgDouble) 1901 QUICK_ENTRY_POINT_INFO(pCmpgFloat) 1902 QUICK_ENTRY_POINT_INFO(pCmplDouble) 1903 QUICK_ENTRY_POINT_INFO(pCmplFloat) 1904 QUICK_ENTRY_POINT_INFO(pFmod) 1905 QUICK_ENTRY_POINT_INFO(pL2d) 1906 QUICK_ENTRY_POINT_INFO(pFmodf) 1907 QUICK_ENTRY_POINT_INFO(pL2f) 1908 QUICK_ENTRY_POINT_INFO(pD2iz) 1909 QUICK_ENTRY_POINT_INFO(pF2iz) 1910 QUICK_ENTRY_POINT_INFO(pIdivmod) 1911 QUICK_ENTRY_POINT_INFO(pD2l) 1912 QUICK_ENTRY_POINT_INFO(pF2l) 1913 QUICK_ENTRY_POINT_INFO(pLdiv) 1914 QUICK_ENTRY_POINT_INFO(pLmod) 1915 QUICK_ENTRY_POINT_INFO(pLmul) 1916 QUICK_ENTRY_POINT_INFO(pShlLong) 1917 QUICK_ENTRY_POINT_INFO(pShrLong) 1918 QUICK_ENTRY_POINT_INFO(pUshrLong) 1919 QUICK_ENTRY_POINT_INFO(pIndexOf) 1920 QUICK_ENTRY_POINT_INFO(pStringCompareTo) 1921 QUICK_ENTRY_POINT_INFO(pMemcpy) 1922 QUICK_ENTRY_POINT_INFO(pQuickImtConflictTrampoline) 1923 QUICK_ENTRY_POINT_INFO(pQuickResolutionTrampoline) 1924 QUICK_ENTRY_POINT_INFO(pQuickToInterpreterBridge) 1925 QUICK_ENTRY_POINT_INFO(pInvokeDirectTrampolineWithAccessCheck) 1926 QUICK_ENTRY_POINT_INFO(pInvokeInterfaceTrampolineWithAccessCheck) 1927 QUICK_ENTRY_POINT_INFO(pInvokeStaticTrampolineWithAccessCheck) 1928 QUICK_ENTRY_POINT_INFO(pInvokeSuperTrampolineWithAccessCheck) 1929 QUICK_ENTRY_POINT_INFO(pInvokeVirtualTrampolineWithAccessCheck) 1930 QUICK_ENTRY_POINT_INFO(pTestSuspend) 1931 QUICK_ENTRY_POINT_INFO(pDeliverException) 1932 QUICK_ENTRY_POINT_INFO(pThrowArrayBounds) 1933 QUICK_ENTRY_POINT_INFO(pThrowDivZero) 1934 QUICK_ENTRY_POINT_INFO(pThrowNoSuchMethod) 1935 QUICK_ENTRY_POINT_INFO(pThrowNullPointer) 1936 QUICK_ENTRY_POINT_INFO(pThrowStackOverflow) 1937 QUICK_ENTRY_POINT_INFO(pA64Load) 1938 QUICK_ENTRY_POINT_INFO(pA64Store) 1939#undef QUICK_ENTRY_POINT_INFO 1940 1941 os << offset; 1942} 1943 1944void Thread::QuickDeliverException() { 1945 // Get exception from thread. 1946 ThrowLocation throw_location; 1947 mirror::Throwable* exception = GetException(&throw_location); 1948 CHECK(exception != nullptr); 1949 // Don't leave exception visible while we try to find the handler, which may cause class 1950 // resolution. 1951 bool is_exception_reported = IsExceptionReportedToInstrumentation(); 1952 ClearException(); 1953 bool is_deoptimization = (exception == GetDeoptimizationException()); 1954 QuickExceptionHandler exception_handler(this, is_deoptimization); 1955 if (is_deoptimization) { 1956 exception_handler.DeoptimizeStack(); 1957 } else { 1958 exception_handler.FindCatch(throw_location, exception, is_exception_reported); 1959 } 1960 exception_handler.UpdateInstrumentationStack(); 1961 exception_handler.DoLongJump(); 1962 LOG(FATAL) << "UNREACHABLE"; 1963} 1964 1965Context* Thread::GetLongJumpContext() { 1966 Context* result = tlsPtr_.long_jump_context; 1967 if (result == nullptr) { 1968 result = Context::Create(); 1969 } else { 1970 tlsPtr_.long_jump_context = nullptr; // Avoid context being shared. 1971 result->Reset(); 1972 } 1973 return result; 1974} 1975 1976// Note: this visitor may return with a method set, but dex_pc_ being DexFile:kDexNoIndex. This is 1977// so we don't abort in a special situation (thinlocked monitor) when dumping the Java stack. 1978struct CurrentMethodVisitor FINAL : public StackVisitor { 1979 CurrentMethodVisitor(Thread* thread, Context* context, bool abort_on_error) 1980 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) 1981 : StackVisitor(thread, context), this_object_(nullptr), method_(nullptr), dex_pc_(0), 1982 abort_on_error_(abort_on_error) {} 1983 bool VisitFrame() OVERRIDE SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1984 mirror::ArtMethod* m = GetMethod(); 1985 if (m->IsRuntimeMethod()) { 1986 // Continue if this is a runtime method. 1987 return true; 1988 } 1989 if (context_ != nullptr) { 1990 this_object_ = GetThisObject(); 1991 } 1992 method_ = m; 1993 dex_pc_ = GetDexPc(abort_on_error_); 1994 return false; 1995 } 1996 mirror::Object* this_object_; 1997 mirror::ArtMethod* method_; 1998 uint32_t dex_pc_; 1999 const bool abort_on_error_; 2000}; 2001 2002mirror::ArtMethod* Thread::GetCurrentMethod(uint32_t* dex_pc, bool abort_on_error) const { 2003 CurrentMethodVisitor visitor(const_cast<Thread*>(this), nullptr, abort_on_error); 2004 visitor.WalkStack(false); 2005 if (dex_pc != nullptr) { 2006 *dex_pc = visitor.dex_pc_; 2007 } 2008 return visitor.method_; 2009} 2010 2011ThrowLocation Thread::GetCurrentLocationForThrow() { 2012 Context* context = GetLongJumpContext(); 2013 CurrentMethodVisitor visitor(this, context, true); 2014 visitor.WalkStack(false); 2015 ReleaseLongJumpContext(context); 2016 return ThrowLocation(visitor.this_object_, visitor.method_, visitor.dex_pc_); 2017} 2018 2019bool Thread::HoldsLock(mirror::Object* object) const { 2020 if (object == nullptr) { 2021 return false; 2022 } 2023 return object->GetLockOwnerThreadId() == GetThreadId(); 2024} 2025 2026// RootVisitor parameters are: (const Object* obj, size_t vreg, const StackVisitor* visitor). 2027template <typename RootVisitor> 2028class ReferenceMapVisitor : public StackVisitor { 2029 public: 2030 ReferenceMapVisitor(Thread* thread, Context* context, const RootVisitor& visitor) 2031 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) 2032 : StackVisitor(thread, context), visitor_(visitor) {} 2033 2034 bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 2035 if (false) { 2036 LOG(INFO) << "Visiting stack roots in " << PrettyMethod(GetMethod()) 2037 << StringPrintf("@ PC:%04x", GetDexPc()); 2038 } 2039 ShadowFrame* shadow_frame = GetCurrentShadowFrame(); 2040 if (shadow_frame != nullptr) { 2041 VisitShadowFrame(shadow_frame); 2042 } else { 2043 VisitQuickFrame(); 2044 } 2045 return true; 2046 } 2047 2048 void VisitShadowFrame(ShadowFrame* shadow_frame) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 2049 mirror::ArtMethod** method_addr = shadow_frame->GetMethodAddress(); 2050 visitor_(reinterpret_cast<mirror::Object**>(method_addr), 0 /*ignored*/, this); 2051 mirror::ArtMethod* m = *method_addr; 2052 DCHECK(m != nullptr); 2053 size_t num_regs = shadow_frame->NumberOfVRegs(); 2054 if (m->IsNative() || shadow_frame->HasReferenceArray()) { 2055 // handle scope for JNI or References for interpreter. 2056 for (size_t reg = 0; reg < num_regs; ++reg) { 2057 mirror::Object* ref = shadow_frame->GetVRegReference(reg); 2058 if (ref != nullptr) { 2059 mirror::Object* new_ref = ref; 2060 visitor_(&new_ref, reg, this); 2061 if (new_ref != ref) { 2062 shadow_frame->SetVRegReference(reg, new_ref); 2063 } 2064 } 2065 } 2066 } else { 2067 // Java method. 2068 // Portable path use DexGcMap and store in Method.native_gc_map_. 2069 const uint8_t* gc_map = m->GetNativeGcMap(); 2070 CHECK(gc_map != nullptr) << PrettyMethod(m); 2071 verifier::DexPcToReferenceMap dex_gc_map(gc_map); 2072 uint32_t dex_pc = shadow_frame->GetDexPC(); 2073 const uint8_t* reg_bitmap = dex_gc_map.FindBitMap(dex_pc); 2074 DCHECK(reg_bitmap != nullptr); 2075 num_regs = std::min(dex_gc_map.RegWidth() * 8, num_regs); 2076 for (size_t reg = 0; reg < num_regs; ++reg) { 2077 if (TestBitmap(reg, reg_bitmap)) { 2078 mirror::Object* ref = shadow_frame->GetVRegReference(reg); 2079 if (ref != nullptr) { 2080 mirror::Object* new_ref = ref; 2081 visitor_(&new_ref, reg, this); 2082 if (new_ref != ref) { 2083 shadow_frame->SetVRegReference(reg, new_ref); 2084 } 2085 } 2086 } 2087 } 2088 } 2089 } 2090 2091 private: 2092 void VisitQuickFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 2093 StackReference<mirror::ArtMethod>* cur_quick_frame = GetCurrentQuickFrame(); 2094 mirror::ArtMethod* m = cur_quick_frame->AsMirrorPtr(); 2095 mirror::ArtMethod* old_method = m; 2096 visitor_(reinterpret_cast<mirror::Object**>(&m), 0 /*ignored*/, this); 2097 if (m != old_method) { 2098 cur_quick_frame->Assign(m); 2099 } 2100 2101 // Process register map (which native and runtime methods don't have) 2102 if (!m->IsNative() && !m->IsRuntimeMethod() && !m->IsProxyMethod()) { 2103 const uint8_t* native_gc_map = m->GetNativeGcMap(); 2104 CHECK(native_gc_map != nullptr) << PrettyMethod(m); 2105 const DexFile::CodeItem* code_item = m->GetCodeItem(); 2106 DCHECK(code_item != nullptr) << PrettyMethod(m); // Can't be nullptr or how would we compile its instructions? 2107 NativePcOffsetToReferenceMap map(native_gc_map); 2108 size_t num_regs = std::min(map.RegWidth() * 8, 2109 static_cast<size_t>(code_item->registers_size_)); 2110 if (num_regs > 0) { 2111 Runtime* runtime = Runtime::Current(); 2112 const void* entry_point = runtime->GetInstrumentation()->GetQuickCodeFor(m); 2113 uintptr_t native_pc_offset = m->NativePcOffset(GetCurrentQuickFramePc(), entry_point); 2114 const uint8_t* reg_bitmap = map.FindBitMap(native_pc_offset); 2115 DCHECK(reg_bitmap != nullptr); 2116 const void* code_pointer = mirror::ArtMethod::EntryPointToCodePointer(entry_point); 2117 const VmapTable vmap_table(m->GetVmapTable(code_pointer)); 2118 QuickMethodFrameInfo frame_info = m->GetQuickFrameInfo(code_pointer); 2119 // For all dex registers in the bitmap 2120 StackReference<mirror::ArtMethod>* cur_quick_frame = GetCurrentQuickFrame(); 2121 DCHECK(cur_quick_frame != nullptr); 2122 for (size_t reg = 0; reg < num_regs; ++reg) { 2123 // Does this register hold a reference? 2124 if (TestBitmap(reg, reg_bitmap)) { 2125 uint32_t vmap_offset; 2126 if (vmap_table.IsInContext(reg, kReferenceVReg, &vmap_offset)) { 2127 int vmap_reg = vmap_table.ComputeRegister(frame_info.CoreSpillMask(), vmap_offset, 2128 kReferenceVReg); 2129 // This is sound as spilled GPRs will be word sized (ie 32 or 64bit). 2130 mirror::Object** ref_addr = reinterpret_cast<mirror::Object**>(GetGPRAddress(vmap_reg)); 2131 if (*ref_addr != nullptr) { 2132 visitor_(ref_addr, reg, this); 2133 } 2134 } else { 2135 StackReference<mirror::Object>* ref_addr = 2136 reinterpret_cast<StackReference<mirror::Object>*>( 2137 GetVRegAddr(cur_quick_frame, code_item, frame_info.CoreSpillMask(), 2138 frame_info.FpSpillMask(), frame_info.FrameSizeInBytes(), reg)); 2139 mirror::Object* ref = ref_addr->AsMirrorPtr(); 2140 if (ref != nullptr) { 2141 mirror::Object* new_ref = ref; 2142 visitor_(&new_ref, reg, this); 2143 if (ref != new_ref) { 2144 ref_addr->Assign(new_ref); 2145 } 2146 } 2147 } 2148 } 2149 } 2150 } 2151 } 2152 } 2153 2154 static bool TestBitmap(size_t reg, const uint8_t* reg_vector) { 2155 return ((reg_vector[reg / kBitsPerByte] >> (reg % kBitsPerByte)) & 0x01) != 0; 2156 } 2157 2158 // Visitor for when we visit a root. 2159 const RootVisitor& visitor_; 2160}; 2161 2162class RootCallbackVisitor { 2163 public: 2164 RootCallbackVisitor(RootCallback* callback, void* arg, uint32_t tid) 2165 : callback_(callback), arg_(arg), tid_(tid) {} 2166 2167 void operator()(mirror::Object** obj, size_t, const StackVisitor*) const { 2168 callback_(obj, arg_, tid_, kRootJavaFrame); 2169 } 2170 2171 private: 2172 RootCallback* const callback_; 2173 void* const arg_; 2174 const uint32_t tid_; 2175}; 2176 2177void Thread::VisitRoots(RootCallback* visitor, void* arg) { 2178 uint32_t thread_id = GetThreadId(); 2179 if (tlsPtr_.opeer != nullptr) { 2180 visitor(&tlsPtr_.opeer, arg, thread_id, kRootThreadObject); 2181 } 2182 if (tlsPtr_.exception != nullptr && tlsPtr_.exception != GetDeoptimizationException()) { 2183 visitor(reinterpret_cast<mirror::Object**>(&tlsPtr_.exception), arg, thread_id, kRootNativeStack); 2184 } 2185 tlsPtr_.throw_location.VisitRoots(visitor, arg); 2186 if (tlsPtr_.monitor_enter_object != nullptr) { 2187 visitor(&tlsPtr_.monitor_enter_object, arg, thread_id, kRootNativeStack); 2188 } 2189 tlsPtr_.jni_env->locals.VisitRoots(visitor, arg, thread_id, kRootJNILocal); 2190 tlsPtr_.jni_env->monitors.VisitRoots(visitor, arg, thread_id, kRootJNIMonitor); 2191 HandleScopeVisitRoots(visitor, arg, thread_id); 2192 if (tlsPtr_.debug_invoke_req != nullptr) { 2193 tlsPtr_.debug_invoke_req->VisitRoots(visitor, arg, thread_id, kRootDebugger); 2194 } 2195 if (tlsPtr_.single_step_control != nullptr) { 2196 tlsPtr_.single_step_control->VisitRoots(visitor, arg, thread_id, kRootDebugger); 2197 } 2198 if (tlsPtr_.deoptimization_shadow_frame != nullptr) { 2199 RootCallbackVisitor visitorToCallback(visitor, arg, thread_id); 2200 ReferenceMapVisitor<RootCallbackVisitor> mapper(this, nullptr, visitorToCallback); 2201 for (ShadowFrame* shadow_frame = tlsPtr_.deoptimization_shadow_frame; shadow_frame != nullptr; 2202 shadow_frame = shadow_frame->GetLink()) { 2203 mapper.VisitShadowFrame(shadow_frame); 2204 } 2205 } 2206 if (tlsPtr_.shadow_frame_under_construction != nullptr) { 2207 RootCallbackVisitor visitorToCallback(visitor, arg, thread_id); 2208 ReferenceMapVisitor<RootCallbackVisitor> mapper(this, nullptr, visitorToCallback); 2209 for (ShadowFrame* shadow_frame = tlsPtr_.shadow_frame_under_construction; 2210 shadow_frame != nullptr; 2211 shadow_frame = shadow_frame->GetLink()) { 2212 mapper.VisitShadowFrame(shadow_frame); 2213 } 2214 } 2215 // Visit roots on this thread's stack 2216 Context* context = GetLongJumpContext(); 2217 RootCallbackVisitor visitorToCallback(visitor, arg, thread_id); 2218 ReferenceMapVisitor<RootCallbackVisitor> mapper(this, context, visitorToCallback); 2219 mapper.WalkStack(); 2220 ReleaseLongJumpContext(context); 2221 for (instrumentation::InstrumentationStackFrame& frame : *GetInstrumentationStack()) { 2222 if (frame.this_object_ != nullptr) { 2223 visitor(&frame.this_object_, arg, thread_id, kRootJavaFrame); 2224 } 2225 DCHECK(frame.method_ != nullptr); 2226 visitor(reinterpret_cast<mirror::Object**>(&frame.method_), arg, thread_id, kRootJavaFrame); 2227 } 2228} 2229 2230static void VerifyRoot(mirror::Object** root, void* /*arg*/, uint32_t /*thread_id*/, 2231 RootType /*root_type*/) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 2232 VerifyObject(*root); 2233} 2234 2235void Thread::VerifyStackImpl() { 2236 std::unique_ptr<Context> context(Context::Create()); 2237 RootCallbackVisitor visitorToCallback(VerifyRoot, Runtime::Current()->GetHeap(), GetThreadId()); 2238 ReferenceMapVisitor<RootCallbackVisitor> mapper(this, context.get(), visitorToCallback); 2239 mapper.WalkStack(); 2240} 2241 2242// Set the stack end to that to be used during a stack overflow 2243void Thread::SetStackEndForStackOverflow() { 2244 // During stack overflow we allow use of the full stack. 2245 if (tlsPtr_.stack_end == tlsPtr_.stack_begin) { 2246 // However, we seem to have already extended to use the full stack. 2247 LOG(ERROR) << "Need to increase kStackOverflowReservedBytes (currently " 2248 << GetStackOverflowReservedBytes(kRuntimeISA) << ")?"; 2249 DumpStack(LOG(ERROR)); 2250 LOG(FATAL) << "Recursive stack overflow."; 2251 } 2252 2253 tlsPtr_.stack_end = tlsPtr_.stack_begin; 2254 2255 // Remove the stack overflow protection if is it set up. 2256 bool implicit_stack_check = !Runtime::Current()->ExplicitStackOverflowChecks(); 2257 if (implicit_stack_check) { 2258 if (!UnprotectStack()) { 2259 LOG(ERROR) << "Unable to remove stack protection for stack overflow"; 2260 } 2261 } 2262} 2263 2264void Thread::SetTlab(byte* start, byte* end) { 2265 DCHECK_LE(start, end); 2266 tlsPtr_.thread_local_start = start; 2267 tlsPtr_.thread_local_pos = tlsPtr_.thread_local_start; 2268 tlsPtr_.thread_local_end = end; 2269 tlsPtr_.thread_local_objects = 0; 2270} 2271 2272bool Thread::HasTlab() const { 2273 bool has_tlab = tlsPtr_.thread_local_pos != nullptr; 2274 if (has_tlab) { 2275 DCHECK(tlsPtr_.thread_local_start != nullptr && tlsPtr_.thread_local_end != nullptr); 2276 } else { 2277 DCHECK(tlsPtr_.thread_local_start == nullptr && tlsPtr_.thread_local_end == nullptr); 2278 } 2279 return has_tlab; 2280} 2281 2282std::ostream& operator<<(std::ostream& os, const Thread& thread) { 2283 thread.ShortDump(os); 2284 return os; 2285} 2286 2287void Thread::ProtectStack() { 2288 void* pregion = tlsPtr_.stack_begin - kStackOverflowProtectedSize; 2289 VLOG(threads) << "Protecting stack at " << pregion; 2290 if (mprotect(pregion, kStackOverflowProtectedSize, PROT_NONE) == -1) { 2291 LOG(FATAL) << "Unable to create protected region in stack for implicit overflow check. " 2292 "Reason: " 2293 << strerror(errno) << " size: " << kStackOverflowProtectedSize; 2294 } 2295} 2296 2297bool Thread::UnprotectStack() { 2298 void* pregion = tlsPtr_.stack_begin - kStackOverflowProtectedSize; 2299 VLOG(threads) << "Unprotecting stack at " << pregion; 2300 return mprotect(pregion, kStackOverflowProtectedSize, PROT_READ|PROT_WRITE) == 0; 2301} 2302 2303 2304} // namespace art 2305