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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 #include "runtime.h"
18 
19 #include <optional>
20 #include <utility>
21 
22 #ifdef __linux__
23 #include <sys/prctl.h>
24 #endif
25 
26 #include <fcntl.h>
27 #include <signal.h>
28 #include <sys/mount.h>
29 #include <sys/syscall.h>
30 
31 #if defined(__APPLE__)
32 #include <crt_externs.h>  // for _NSGetEnviron
33 #endif
34 
35 #include <android-base/properties.h>
36 #include <android-base/strings.h>
37 #include <string.h>
38 
39 #include <cstdio>
40 #include <cstdlib>
41 #include <limits>
42 #include <thread>
43 #include <unordered_set>
44 #include <vector>
45 
46 #include "arch/arm/registers_arm.h"
47 #include "arch/arm64/registers_arm64.h"
48 #include "arch/context.h"
49 #include "arch/instruction_set_features.h"
50 #include "arch/x86/registers_x86.h"
51 #include "arch/x86_64/registers_x86_64.h"
52 #include "art_field-inl.h"
53 #include "art_method-inl.h"
54 #include "asm_support.h"
55 #include "base/aborting.h"
56 #include "base/arena_allocator.h"
57 #include "base/atomic.h"
58 #include "base/dumpable.h"
59 #include "base/file_utils.h"
60 #include "base/flags.h"
61 #include "base/malloc_arena_pool.h"
62 #include "base/mem_map_arena_pool.h"
63 #include "base/memory_tool.h"
64 #include "base/mutex.h"
65 #include "base/os.h"
66 #include "base/pointer_size.h"
67 #include "base/quasi_atomic.h"
68 #include "base/sdk_version.h"
69 #include "base/stl_util.h"
70 #include "base/systrace.h"
71 #include "base/unix_file/fd_file.h"
72 #include "base/utils.h"
73 #include "class_linker-inl.h"
74 #include "class_root-inl.h"
75 #include "compiler_callbacks.h"
76 #include "debugger.h"
77 #include "dex/art_dex_file_loader.h"
78 #include "dex/dex_file_loader.h"
79 #include "entrypoints/entrypoint_utils-inl.h"
80 #include "entrypoints/runtime_asm_entrypoints.h"
81 #include "experimental_flags.h"
82 #include "fault_handler.h"
83 #include "gc/accounting/card_table-inl.h"
84 #include "gc/heap.h"
85 #include "gc/scoped_gc_critical_section.h"
86 #include "gc/space/image_space.h"
87 #include "gc/space/space-inl.h"
88 #include "gc/system_weak.h"
89 #include "gc/task_processor.h"
90 #include "handle_scope-inl.h"
91 #include "hidden_api.h"
92 #include "indirect_reference_table.h"
93 #include "instrumentation.h"
94 #include "intern_table-inl.h"
95 #include "interpreter/interpreter.h"
96 #include "jit/jit.h"
97 #include "jit/jit_code_cache.h"
98 #include "jit/profile_saver.h"
99 #include "jni/java_vm_ext.h"
100 #include "jni/jni_id_manager.h"
101 #include "jni_id_type.h"
102 #include "linear_alloc.h"
103 #include "memory_representation.h"
104 #include "metrics/statsd.h"
105 #include "mirror/array.h"
106 #include "mirror/class-alloc-inl.h"
107 #include "mirror/class-inl.h"
108 #include "mirror/class_ext.h"
109 #include "mirror/class_loader-inl.h"
110 #include "mirror/emulated_stack_frame.h"
111 #include "mirror/field.h"
112 #include "mirror/method.h"
113 #include "mirror/method_handle_impl.h"
114 #include "mirror/method_handles_lookup.h"
115 #include "mirror/method_type.h"
116 #include "mirror/stack_trace_element.h"
117 #include "mirror/throwable.h"
118 #include "mirror/var_handle.h"
119 #include "monitor.h"
120 #include "native/dalvik_system_BaseDexClassLoader.h"
121 #include "native/dalvik_system_DexFile.h"
122 #include "native/dalvik_system_VMDebug.h"
123 #include "native/dalvik_system_VMRuntime.h"
124 #include "native/dalvik_system_VMStack.h"
125 #include "native/dalvik_system_ZygoteHooks.h"
126 #include "native/java_lang_Class.h"
127 #include "native/java_lang_Object.h"
128 #include "native/java_lang_StackStreamFactory.h"
129 #include "native/java_lang_String.h"
130 #include "native/java_lang_StringFactory.h"
131 #include "native/java_lang_System.h"
132 #include "native/java_lang_Thread.h"
133 #include "native/java_lang_Throwable.h"
134 #include "native/java_lang_VMClassLoader.h"
135 #include "native/java_lang_invoke_MethodHandle.h"
136 #include "native/java_lang_invoke_MethodHandleImpl.h"
137 #include "native/java_lang_ref_FinalizerReference.h"
138 #include "native/java_lang_ref_Reference.h"
139 #include "native/java_lang_reflect_Array.h"
140 #include "native/java_lang_reflect_Constructor.h"
141 #include "native/java_lang_reflect_Executable.h"
142 #include "native/java_lang_reflect_Field.h"
143 #include "native/java_lang_reflect_Method.h"
144 #include "native/java_lang_reflect_Parameter.h"
145 #include "native/java_lang_reflect_Proxy.h"
146 #include "native/java_util_concurrent_atomic_AtomicLong.h"
147 #include "native/jdk_internal_misc_Unsafe.h"
148 #include "native/libcore_io_Memory.h"
149 #include "native/libcore_util_CharsetUtils.h"
150 #include "native/org_apache_harmony_dalvik_ddmc_DdmServer.h"
151 #include "native/org_apache_harmony_dalvik_ddmc_DdmVmInternal.h"
152 #include "native/sun_misc_Unsafe.h"
153 #include "native_bridge_art_interface.h"
154 #include "native_stack_dump.h"
155 #include "nativehelper/scoped_local_ref.h"
156 #include "nterp_helpers.h"
157 #include "oat/aot_class_linker.h"
158 #include "oat/elf_file.h"
159 #include "oat/image-inl.h"
160 #include "oat/oat.h"
161 #include "oat/oat_file_manager.h"
162 #include "oat/oat_quick_method_header.h"
163 #include "object_callbacks.h"
164 #include "odr_statslog/odr_statslog.h"
165 #include "parsed_options.h"
166 #include "quick/quick_method_frame_info.h"
167 #include "reflection.h"
168 #include "runtime_callbacks.h"
169 #include "runtime_common.h"
170 #include "runtime_image.h"
171 #include "runtime_intrinsics.h"
172 #include "runtime_options.h"
173 #include "scoped_thread_state_change-inl.h"
174 #include "sigchain.h"
175 #include "signal_catcher.h"
176 #include "signal_set.h"
177 #include "thread.h"
178 #include "thread_list.h"
179 #include "ti/agent.h"
180 #include "trace.h"
181 #include "vdex_file.h"
182 #include "verifier/class_verifier.h"
183 #include "well_known_classes-inl.h"
184 
185 #ifdef ART_TARGET_ANDROID
186 #include <android/api-level.h>
187 #include <android/set_abort_message.h>
188 #include "com_android_apex.h"
189 namespace apex = com::android::apex;
190 
191 #endif
192 
193 // Static asserts to check the values of generated assembly-support macros.
194 #define ASM_DEFINE(NAME, EXPR) static_assert((NAME) == (EXPR), "Unexpected value of " #NAME);
195 #include "asm_defines.def"
196 #undef ASM_DEFINE
197 
198 namespace art HIDDEN {
199 
200 // If a signal isn't handled properly, enable a handler that attempts to dump the Java stack.
201 static constexpr bool kEnableJavaStackTraceHandler = false;
202 // Tuned by compiling GmsCore under perf and measuring time spent in DescriptorEquals for class
203 // linking.
204 static constexpr double kLowMemoryMinLoadFactor = 0.5;
205 static constexpr double kLowMemoryMaxLoadFactor = 0.8;
206 static constexpr double kNormalMinLoadFactor = 0.4;
207 static constexpr double kNormalMaxLoadFactor = 0.7;
208 
209 #ifdef ART_PAGE_SIZE_AGNOSTIC
210 // Declare the constant as ALWAYS_HIDDEN to ensure it isn't visible from outside libart.so.
211 const size_t PageSize::value_ ALWAYS_HIDDEN = GetPageSizeSlow();
212 PageSize gPageSize ALWAYS_HIDDEN;
213 #endif
214 
215 Runtime* Runtime::instance_ = nullptr;
216 
217 struct TraceConfig {
218   Trace::TraceMode trace_mode;
219   TraceOutputMode trace_output_mode;
220   std::string trace_file;
221   size_t trace_file_size;
222   TraceClockSource clock_source;
223 };
224 
225 namespace {
226 
227 #ifdef __APPLE__
GetEnviron()228 inline char** GetEnviron() {
229   // When Google Test is built as a framework on MacOS X, the environ variable
230   // is unavailable. Apple's documentation (man environ) recommends using
231   // _NSGetEnviron() instead.
232   return *_NSGetEnviron();
233 }
234 #else
235 // Some POSIX platforms expect you to declare environ. extern "C" makes
236 // it reside in the global namespace.
237 EXPORT extern "C" char** environ;
238 inline char** GetEnviron() { return environ; }
239 #endif
240 
CheckConstants()241 void CheckConstants() {
242   CHECK_EQ(mirror::Array::kFirstElementOffset, mirror::Array::FirstElementOffset());
243 }
244 
245 }  // namespace
246 
Runtime()247 Runtime::Runtime()
248     : resolution_method_(nullptr),
249       imt_conflict_method_(nullptr),
250       imt_unimplemented_method_(nullptr),
251       instruction_set_(InstructionSet::kNone),
252       compiler_callbacks_(nullptr),
253       is_zygote_(false),
254       is_primary_zygote_(false),
255       is_system_server_(false),
256       must_relocate_(false),
257       is_concurrent_gc_enabled_(true),
258       is_explicit_gc_disabled_(false),
259       is_eagerly_release_explicit_gc_disabled_(false),
260       image_dex2oat_enabled_(true),
261       default_stack_size_(0),
262       heap_(nullptr),
263       max_spins_before_thin_lock_inflation_(Monitor::kDefaultMaxSpinsBeforeThinLockInflation),
264       monitor_list_(nullptr),
265       monitor_pool_(nullptr),
266       thread_list_(nullptr),
267       intern_table_(nullptr),
268       class_linker_(nullptr),
269       signal_catcher_(nullptr),
270       java_vm_(nullptr),
271       thread_pool_ref_count_(0u),
272       fault_message_(nullptr),
273       threads_being_born_(0),
274       shutdown_cond_(new ConditionVariable("Runtime shutdown", *Locks::runtime_shutdown_lock_)),
275       shutting_down_(false),
276       shutting_down_started_(false),
277       started_(false),
278       finished_starting_(false),
279       vfprintf_(nullptr),
280       exit_(nullptr),
281       abort_(nullptr),
282       stats_enabled_(false),
283       is_running_on_memory_tool_(kRunningOnMemoryTool),
284       instrumentation_(),
285       main_thread_group_(nullptr),
286       system_thread_group_(nullptr),
287       system_class_loader_(nullptr),
288       dump_gc_performance_on_shutdown_(false),
289       active_transaction_(false),
290       verify_(verifier::VerifyMode::kNone),
291       target_sdk_version_(static_cast<uint32_t>(SdkVersion::kUnset)),
292       compat_framework_(),
293       implicit_null_checks_(false),
294       implicit_so_checks_(false),
295       implicit_suspend_checks_(false),
296       no_sig_chain_(false),
297       force_native_bridge_(false),
298       is_native_bridge_loaded_(false),
299       is_native_debuggable_(false),
300       async_exceptions_thrown_(false),
301       non_standard_exits_enabled_(false),
302       runtime_debug_state_(RuntimeDebugState::kNonJavaDebuggable),
303       monitor_timeout_enable_(false),
304       monitor_timeout_ns_(0),
305       zygote_max_failed_boots_(0),
306       experimental_flags_(ExperimentalFlags::kNone),
307       oat_file_manager_(nullptr),
308       is_low_memory_mode_(false),
309       madvise_willneed_total_dex_size_(0),
310       madvise_willneed_odex_filesize_(0),
311       madvise_willneed_art_filesize_(0),
312       safe_mode_(false),
313       hidden_api_policy_(hiddenapi::EnforcementPolicy::kDisabled),
314       core_platform_api_policy_(hiddenapi::EnforcementPolicy::kDisabled),
315       test_api_policy_(hiddenapi::EnforcementPolicy::kDisabled),
316       dedupe_hidden_api_warnings_(true),
317       hidden_api_access_event_log_rate_(0),
318       dump_native_stack_on_sig_quit_(true),
319       // Initially assume we perceive jank in case the process state is never updated.
320       process_state_(kProcessStateJankPerceptible),
321       zygote_no_threads_(false),
322       verifier_logging_threshold_ms_(100),
323       verifier_missing_kthrow_fatal_(false),
324       perfetto_hprof_enabled_(false),
325       perfetto_javaheapprof_enabled_(false),
326       out_of_memory_error_hook_(nullptr) {
327   static_assert(Runtime::kCalleeSaveSize ==
328                     static_cast<uint32_t>(CalleeSaveType::kLastCalleeSaveType), "Unexpected size");
329   CheckConstants();
330 
331   std::fill(callee_save_methods_, callee_save_methods_ + arraysize(callee_save_methods_), 0u);
332   interpreter::CheckInterpreterAsmConstants();
333   callbacks_.reset(new RuntimeCallbacks());
334   for (size_t i = 0; i <= static_cast<size_t>(DeoptimizationKind::kLast); ++i) {
335     deoptimization_counts_[i] = 0u;
336   }
337 }
338 
~Runtime()339 Runtime::~Runtime() {
340   ScopedTrace trace("Runtime shutdown");
341   if (is_native_bridge_loaded_) {
342     UnloadNativeBridge();
343   }
344 
345   Thread* self = Thread::Current();
346   const bool attach_shutdown_thread = self == nullptr;
347   if (attach_shutdown_thread) {
348     // We can only create a peer if the runtime is actually started. This is only not true during
349     // some tests. If there is extreme memory pressure the allocation of the thread peer can fail.
350     // In this case we will just try again without allocating a peer so that shutdown can continue.
351     // Very few things are actually capable of distinguishing between the peer & peerless states so
352     // this should be fine.
353     // Running callbacks is prone to deadlocks in libjdwp tests that need an event handler lock to
354     // process any event. We also need to enter a GCCriticalSection when processing certain events
355     // (for ex: removing the last breakpoint). These two restrictions together make the tear down
356     // of the jdwp tests deadlock prone if we fail to finish Thread::Attach callback.
357     // (TODO:b/251163712) Remove this once we update deopt manager to not use GCCriticalSection.
358     bool thread_attached = AttachCurrentThread("Shutdown thread",
359                                                /* as_daemon= */ false,
360                                                GetSystemThreadGroup(),
361                                                /* create_peer= */ IsStarted(),
362                                                /* should_run_callbacks= */ false);
363     if (UNLIKELY(!thread_attached)) {
364       LOG(WARNING) << "Failed to attach shutdown thread. Trying again without a peer.";
365       CHECK(AttachCurrentThread("Shutdown thread (no java peer)",
366                                 /* as_daemon= */   false,
367                                 /* thread_group=*/ nullptr,
368                                 /* create_peer= */ false));
369     }
370     self = Thread::Current();
371   } else {
372     LOG(WARNING) << "Current thread not detached in Runtime shutdown";
373   }
374 
375   if (dump_gc_performance_on_shutdown_) {
376     heap_->CalculatePreGcWeightedAllocatedBytes();
377     uint64_t process_cpu_end_time = ProcessCpuNanoTime();
378     ScopedLogSeverity sls(LogSeverity::INFO);
379     // This can't be called from the Heap destructor below because it
380     // could call RosAlloc::InspectAll() which needs the thread_list
381     // to be still alive.
382     heap_->DumpGcPerformanceInfo(LOG_STREAM(INFO));
383 
384     uint64_t process_cpu_time = process_cpu_end_time - heap_->GetProcessCpuStartTime();
385     uint64_t gc_cpu_time = heap_->GetTotalGcCpuTime();
386     float ratio = static_cast<float>(gc_cpu_time) / process_cpu_time;
387     LOG_STREAM(INFO) << "GC CPU time " << PrettyDuration(gc_cpu_time)
388         << " out of process CPU time " << PrettyDuration(process_cpu_time)
389         << " (" << ratio << ")"
390         << "\n";
391     double pre_gc_weighted_allocated_bytes =
392         heap_->GetPreGcWeightedAllocatedBytes() / process_cpu_time;
393     // Here we don't use process_cpu_time for normalization, because VM shutdown is not a real
394     // GC. Both numerator and denominator take into account until the end of the last GC,
395     // instead of the whole process life time like pre_gc_weighted_allocated_bytes.
396     double post_gc_weighted_allocated_bytes =
397         heap_->GetPostGcWeightedAllocatedBytes() /
398           (heap_->GetPostGCLastProcessCpuTime() - heap_->GetProcessCpuStartTime());
399 
400     LOG_STREAM(INFO) << "Average bytes allocated at GC start, weighted by CPU time between GCs: "
401         << static_cast<uint64_t>(pre_gc_weighted_allocated_bytes)
402         << " (" <<  PrettySize(pre_gc_weighted_allocated_bytes)  << ")";
403     LOG_STREAM(INFO) << "Average bytes allocated at GC end, weighted by CPU time between GCs: "
404         << static_cast<uint64_t>(post_gc_weighted_allocated_bytes)
405         << " (" <<  PrettySize(post_gc_weighted_allocated_bytes)  << ")"
406         << "\n";
407   }
408 
409   // Wait for the workers of thread pools to be created since there can't be any
410   // threads attaching during shutdown.
411   WaitForThreadPoolWorkersToStart();
412   if (jit_ != nullptr) {
413     jit_->WaitForWorkersToBeCreated();
414     // Stop the profile saver thread before marking the runtime as shutting down.
415     // The saver will try to dump the profiles before being sopped and that
416     // requires holding the mutator lock.
417     jit_->StopProfileSaver();
418     // Delete thread pool before the thread list since we don't want to wait forever on the
419     // JIT compiler threads. Also this should be run before marking the runtime
420     // as shutting down as some tasks may require mutator access.
421     jit_->DeleteThreadPool();
422   }
423   if (oat_file_manager_ != nullptr) {
424     oat_file_manager_->WaitForWorkersToBeCreated();
425   }
426   // Disable GC before deleting the thread-pool and shutting down runtime as it
427   // restricts attaching new threads.
428   heap_->DisableGCForShutdown();
429   heap_->WaitForWorkersToBeCreated();
430   // Make sure to let the GC complete if it is running.
431   heap_->WaitForGcToComplete(gc::kGcCauseBackground, self);
432 
433   // Shutdown any trace before SetShuttingDown. Trace uses thread pool workers to flush entries
434   // and we want to make sure they are fully created. Threads cannot attach while shutting down.
435   Trace::Shutdown();
436 
437   {
438     ScopedTrace trace2("Wait for shutdown cond");
439     MutexLock mu(self, *Locks::runtime_shutdown_lock_);
440     shutting_down_started_ = true;
441     while (threads_being_born_ > 0) {
442       shutdown_cond_->Wait(self);
443     }
444     SetShuttingDown();
445   }
446   // Shutdown and wait for the daemons.
447   CHECK(self != nullptr);
448   if (IsFinishedStarting()) {
449     ScopedTrace trace2("Waiting for Daemons");
450     self->ClearException();
451     ScopedObjectAccess soa(self);
452     WellKnownClasses::java_lang_Daemons_stop->InvokeStatic<'V'>(self);
453   }
454 
455   // Report death. Clients may require a working thread, still, so do it before GC completes and
456   // all non-daemon threads are done.
457   {
458     ScopedObjectAccess soa(self);
459     callbacks_->NextRuntimePhase(RuntimePhaseCallback::RuntimePhase::kDeath);
460   }
461 
462   // Delete thread pools before detaching the current thread in case tasks
463   // getting deleted need to have access to Thread::Current.
464   heap_->DeleteThreadPool();
465   if (oat_file_manager_ != nullptr) {
466     oat_file_manager_->DeleteThreadPool();
467   }
468   DeleteThreadPool();
469   CHECK(thread_pool_ == nullptr);
470 
471   if (attach_shutdown_thread) {
472     DetachCurrentThread(/* should_run_callbacks= */ false);
473     self = nullptr;
474   }
475 
476   // Make sure our internal threads are dead before we start tearing down things they're using.
477   GetRuntimeCallbacks()->StopDebugger();
478   // Deletion ordering is tricky. Null out everything we've deleted.
479   delete signal_catcher_;
480   signal_catcher_ = nullptr;
481 
482   // Shutdown metrics reporting.
483   metrics_reporter_.reset();
484 
485   // Make sure all other non-daemon threads have terminated, and all daemon threads are suspended.
486   // Also wait for daemon threads to quiesce, so that in addition to being "suspended", they
487   // no longer access monitor and thread list data structures. We leak user daemon threads
488   // themselves, since we have no mechanism for shutting them down.
489   {
490     ScopedTrace trace2("Delete thread list");
491     thread_list_->ShutDown();
492   }
493 
494   // TODO Maybe do some locking.
495   for (auto& agent : agents_) {
496     agent->Unload();
497   }
498 
499   // TODO Maybe do some locking
500   for (auto& plugin : plugins_) {
501     plugin.Unload();
502   }
503 
504   // Finally delete the thread list.
505   // Thread_list_ can be accessed by "suspended" threads, e.g. in InflateThinLocked.
506   // We assume that by this point, we've waited long enough for things to quiesce.
507   delete thread_list_;
508   thread_list_ = nullptr;
509 
510   // Delete the JIT after thread list to ensure that there is no remaining threads which could be
511   // accessing the instrumentation when we delete it.
512   if (jit_ != nullptr) {
513     VLOG(jit) << "Deleting jit";
514     jit_.reset(nullptr);
515     jit_code_cache_.reset(nullptr);
516   }
517 
518   // Shutdown the fault manager if it was initialized.
519   fault_manager.Shutdown();
520 
521   ScopedTrace trace2("Delete state");
522   delete monitor_list_;
523   monitor_list_ = nullptr;
524   delete monitor_pool_;
525   monitor_pool_ = nullptr;
526   delete class_linker_;
527   class_linker_ = nullptr;
528   delete small_lrt_allocator_;
529   small_lrt_allocator_ = nullptr;
530   delete heap_;
531   heap_ = nullptr;
532   delete intern_table_;
533   intern_table_ = nullptr;
534   delete oat_file_manager_;
535   oat_file_manager_ = nullptr;
536   Thread::Shutdown();
537   QuasiAtomic::Shutdown();
538 
539   // Destroy allocators before shutting down the MemMap because they may use it.
540   java_vm_.reset();
541   linear_alloc_.reset();
542   delete ReleaseStartupLinearAlloc();
543   linear_alloc_arena_pool_.reset();
544   arena_pool_.reset();
545   jit_arena_pool_.reset();
546   protected_fault_page_.Reset();
547   MemMap::Shutdown();
548 
549   // TODO: acquire a static mutex on Runtime to avoid racing.
550   CHECK(instance_ == nullptr || instance_ == this);
551   instance_ = nullptr;
552 
553   // Well-known classes must be deleted or it is impossible to successfully start another Runtime
554   // instance. We rely on a small initialization order issue in Runtime::Start() that requires
555   // elements of WellKnownClasses to be null, see b/65500943.
556   WellKnownClasses::Clear();
557 
558 #ifdef ART_PAGE_SIZE_AGNOSTIC
559   // This is added to ensure no test is able to access gPageSize prior to initializing Runtime just
560   // because a Runtime instance was created (and subsequently destroyed) by another test.
561   gPageSize.DisallowAccess();
562 #endif
563 }
564 
565 struct AbortState {
Dumpart::AbortState566   void Dump(std::ostream& os) const {
567     if (gAborting > 1) {
568       os << "Runtime aborting --- recursively, so no thread-specific detail!\n";
569       DumpRecursiveAbort(os);
570       return;
571     }
572     gAborting++;
573     os << "Runtime aborting...\n";
574     if (Runtime::Current() == nullptr) {
575       os << "(Runtime does not yet exist!)\n";
576       DumpNativeStack(os, GetTid(), "  native: ", nullptr);
577       return;
578     }
579     Thread* self = Thread::Current();
580 
581     // Dump all threads first and then the aborting thread. While this is counter the logical flow,
582     // it improves the chance of relevant data surviving in the Android logs.
583 
584     DumpAllThreads(os, self);
585 
586     if (self == nullptr) {
587       os << "(Aborting thread was not attached to runtime!)\n";
588       DumpNativeStack(os, GetTid(), "  native: ", nullptr);
589     } else {
590       os << "Aborting thread:\n";
591       if (Locks::mutator_lock_->IsExclusiveHeld(self) || Locks::mutator_lock_->IsSharedHeld(self)) {
592         DumpThread(os, self);
593       } else {
594         if (Locks::mutator_lock_->SharedTryLock(self)) {
595           DumpThread(os, self);
596           Locks::mutator_lock_->SharedUnlock(self);
597         }
598       }
599     }
600   }
601 
602   // No thread-safety analysis as we do explicitly test for holding the mutator lock.
DumpThreadart::AbortState603   void DumpThread(std::ostream& os, Thread* self) const NO_THREAD_SAFETY_ANALYSIS {
604     DCHECK(Locks::mutator_lock_->IsExclusiveHeld(self) || Locks::mutator_lock_->IsSharedHeld(self));
605     self->Dump(os);
606     if (self->IsExceptionPending()) {
607       mirror::Throwable* exception = self->GetException();
608       os << "Pending exception " << exception->Dump();
609     }
610   }
611 
DumpAllThreadsart::AbortState612   void DumpAllThreads(std::ostream& os, Thread* self) const {
613     Runtime* runtime = Runtime::Current();
614     if (runtime != nullptr) {
615       ThreadList* thread_list = runtime->GetThreadList();
616       if (thread_list != nullptr) {
617         // Dump requires ThreadListLock and ThreadSuspendCountLock to not be held (they will be
618         // grabbed).
619         // TODO(b/134167395): Change Dump to work with the locks held, and have a loop with timeout
620         //                    acquiring the locks.
621         bool tll_already_held = Locks::thread_list_lock_->IsExclusiveHeld(self);
622         bool tscl_already_held = Locks::thread_suspend_count_lock_->IsExclusiveHeld(self);
623         if (tll_already_held || tscl_already_held) {
624           os << "Skipping all-threads dump as locks are held:"
625              << (tll_already_held ? "" : " thread_list_lock")
626              << (tscl_already_held ? "" : " thread_suspend_count_lock")
627              << "\n";
628           return;
629         }
630         bool ml_already_exlusively_held = Locks::mutator_lock_->IsExclusiveHeld(self);
631         if (ml_already_exlusively_held) {
632           os << "Skipping all-threads dump as mutator lock is exclusively held.";
633           return;
634         }
635         bool ml_already_held = Locks::mutator_lock_->IsSharedHeld(self);
636         if (!ml_already_held) {
637           os << "Dumping all threads without mutator lock held\n";
638         }
639         os << "All threads:\n";
640         thread_list->Dump(os);
641       }
642     }
643   }
644 
645   // For recursive aborts.
DumpRecursiveAbortart::AbortState646   void DumpRecursiveAbort(std::ostream& os) const NO_THREAD_SAFETY_ANALYSIS {
647     // The only thing we'll attempt is dumping the native stack of the current thread. We will only
648     // try this if we haven't exceeded an arbitrary amount of recursions, to recover and actually
649     // die.
650     // Note: as we're using a global counter for the recursive abort detection, there is a potential
651     //       race here and it is not OK to just print when the counter is "2" (one from
652     //       Runtime::Abort(), one from previous Dump() call). Use a number that seems large enough.
653     static constexpr size_t kOnlyPrintWhenRecursionLessThan = 100u;
654     if (gAborting < kOnlyPrintWhenRecursionLessThan) {
655       gAborting++;
656       DumpNativeStack(os, GetTid());
657     }
658   }
659 };
660 
SetAbortMessage(const char * msg)661 void Runtime::SetAbortMessage(const char* msg) {
662   auto old_value = gAborting.fetch_add(1);  // set before taking any locks
663 
664   // Only set the first abort message.
665   if (old_value == 0) {
666 #ifdef ART_TARGET_ANDROID
667     android_set_abort_message(msg);
668 #endif
669     // Set the runtime fault message in case our unexpected-signal code will run.
670     Runtime* current = Runtime::Current();
671     if (current != nullptr) {
672       current->SetFaultMessage(msg);
673     }
674   }
675 }
676 
Abort(const char * msg)677 void Runtime::Abort(const char* msg) {
678   SetAbortMessage(msg);
679 
680   // May be coming from an unattached thread.
681   if (Thread::Current() == nullptr) {
682     Runtime* current = Runtime::Current();
683     if (current != nullptr && current->IsStarted() && !current->IsShuttingDownUnsafe()) {
684       // We do not flag this to the unexpected-signal handler so that that may dump the stack.
685       abort();
686       UNREACHABLE();
687     }
688   }
689 
690   {
691     // Ensure that we don't have multiple threads trying to abort at once,
692     // which would result in significantly worse diagnostics.
693     ScopedThreadStateChange tsc(Thread::Current(), ThreadState::kNativeForAbort);
694     Locks::abort_lock_->ExclusiveLock(Thread::Current());
695   }
696 
697   // Get any pending output out of the way.
698   fflush(nullptr);
699 
700   // Many people have difficulty distinguish aborts from crashes,
701   // so be explicit.
702   // Note: use cerr on the host to print log lines immediately, so we get at least some output
703   //       in case of recursive aborts. We lose annotation with the source file and line number
704   //       here, which is a minor issue. The same is significantly more complicated on device,
705   //       which is why we ignore the issue there.
706   AbortState state;
707   if (kIsTargetBuild) {
708     LOG(FATAL_WITHOUT_ABORT) << Dumpable<AbortState>(state);
709   } else {
710     std::cerr << Dumpable<AbortState>(state);
711   }
712 
713   // Sometimes we dump long messages, and the Android abort message only retains the first line.
714   // In those cases, just log the message again, to avoid logcat limits.
715   if (msg != nullptr && strchr(msg, '\n') != nullptr) {
716     LOG(FATAL_WITHOUT_ABORT) << msg;
717   }
718 
719   FlagRuntimeAbort();
720 
721   // Call the abort hook if we have one.
722   if (Runtime::Current() != nullptr && Runtime::Current()->abort_ != nullptr) {
723     LOG(FATAL_WITHOUT_ABORT) << "Calling abort hook...";
724     Runtime::Current()->abort_();
725     // notreached
726     LOG(FATAL_WITHOUT_ABORT) << "Unexpectedly returned from abort hook!";
727   }
728 
729   abort();
730   // notreached
731 }
732 
733 /**
734  * Update entrypoints of methods before the first fork. This
735  * helps sharing pages where ArtMethods are allocated between the zygote and
736  * forked apps.
737  */
738 class UpdateMethodsPreFirstForkVisitor : public ClassVisitor {
739  public:
UpdateMethodsPreFirstForkVisitor(ClassLinker * class_linker)740   explicit UpdateMethodsPreFirstForkVisitor(ClassLinker* class_linker)
741       : class_linker_(class_linker),
742         can_use_nterp_(interpreter::CanRuntimeUseNterp()) {}
743 
operator ()(ObjPtr<mirror::Class> klass)744   bool operator()(ObjPtr<mirror::Class> klass) override REQUIRES_SHARED(Locks::mutator_lock_) {
745     bool is_initialized = klass->IsVisiblyInitialized();
746     for (ArtMethod& method : klass->GetDeclaredMethods(kRuntimePointerSize)) {
747       if (!is_initialized && method.NeedsClinitCheckBeforeCall() && can_use_nterp_) {
748         const void* existing = method.GetEntryPointFromQuickCompiledCode();
749         if (class_linker_->IsQuickResolutionStub(existing) && CanMethodUseNterp(&method)) {
750           method.SetEntryPointFromQuickCompiledCode(interpreter::GetNterpWithClinitEntryPoint());
751         }
752       }
753     }
754     return true;
755   }
756 
757  private:
758   ClassLinker* const class_linker_;
759   const bool can_use_nterp_;
760 
761   DISALLOW_COPY_AND_ASSIGN(UpdateMethodsPreFirstForkVisitor);
762 };
763 
764 // Wait until the kernel thinks we are single-threaded again.
WaitUntilSingleThreaded()765 static void WaitUntilSingleThreaded() {
766 #if defined(__linux__)
767   // Read num_threads field from /proc/self/stat, avoiding higher-level IO libraries that may
768   // break atomicity of the read.
769   static constexpr size_t kNumTries = 2000;
770   static constexpr size_t kNumThreadsIndex = 20;
771   static constexpr size_t BUF_SIZE = 500;
772   static constexpr size_t BUF_PRINT_SIZE = 150;  // Only log this much on failure to limit length.
773   static_assert(BUF_SIZE > BUF_PRINT_SIZE);
774   char buf[BUF_SIZE];
775   size_t bytes_read = 0;
776   uint64_t millis = 0;
777   for (size_t tries = 0; tries < kNumTries; ++tries) {
778     bytes_read = GetOsThreadStat(getpid(), buf, BUF_SIZE);
779     CHECK_NE(bytes_read, 0u);
780     size_t pos = 0;
781     while (pos < bytes_read && buf[pos++] != ')') {}
782     ++pos;
783     // We're now positioned at the beginning of the third field. Don't count blanks embedded in
784     // second (command) field.
785     size_t blanks_seen = 2;
786     while (pos < bytes_read && blanks_seen < kNumThreadsIndex - 1) {
787       if (buf[pos++] == ' ') {
788         ++blanks_seen;
789       }
790     }
791     CHECK(pos < bytes_read - 2);
792     // pos is first character of num_threads field.
793     CHECK_EQ(buf[pos + 1], ' ');  // We never have more than single-digit threads here.
794     if (buf[pos] == '1') {
795       return;  //  num_threads == 1; success.
796     }
797     if (millis == 0) {
798       millis = MilliTime();
799     }
800     usleep(tries < 10 ? 1000 : 2000);
801   }
802   buf[std::min(BUF_PRINT_SIZE, bytes_read)] = '\0';  // Truncate buf before printing.
803   LOG(ERROR) << "Not single threaded: bytes_read = " << bytes_read << " stat contents = \"" << buf
804              << "...\"";
805   LOG(ERROR) << "Other threads' abbreviated stats: " << GetOtherThreadOsStats();
806   bytes_read = GetOsThreadStat(getpid(), buf, BUF_PRINT_SIZE);
807   CHECK_NE(bytes_read, 0u);
808   LOG(ERROR) << "After re-read: bytes_read = " << bytes_read << " stat contents = \"" << buf
809              << "...\"";
810   LOG(FATAL) << "Failed to reach single-threaded state: wait_time = " << MilliTime() - millis;
811 #else  // Not Linux; shouldn't matter, but this has a high probability of working slowly.
812   usleep(20'000);
813 #endif
814 }
815 
PreZygoteFork()816 void Runtime::PreZygoteFork() {
817   if (GetJit() != nullptr) {
818     GetJit()->PreZygoteFork();
819   }
820   // All other threads have already been joined, but they may not have finished
821   // removing themselves from the thread list. Wait until the other threads have completely
822   // finished, and are no longer in the thread list.
823   // TODO: Since the threads Unregister() themselves before exiting, the first wait should be
824   // unnecessary. But since we're reading from a /proc entry that's concurrently changing, for
825   // now we play this as safe as possible.
826   ThreadList* tl = GetThreadList();
827   {
828     Thread* self = Thread::Current();
829     MutexLock mu(self, *Locks::thread_list_lock_);
830     tl->WaitForUnregisterToComplete(self);
831     if (kIsDebugBuild) {
832       auto list = tl->GetList();
833       if (list.size() != 1) {
834         for (Thread* t : list) {
835           std::string name;
836           t->GetThreadName(name);
837           LOG(ERROR) << "Remaining pre-fork thread: " << name;
838         }
839       }
840     }
841     CHECK_EQ(tl->Size(), 1u);
842     // And then wait until the kernel thinks the threads are gone.
843     WaitUntilSingleThreaded();
844   }
845 
846   if (!heap_->HasZygoteSpace()) {
847     Thread* self = Thread::Current();
848     // This is the first fork. Update ArtMethods in the boot classpath now to
849     // avoid having forked apps dirty the memory.
850 
851     // Ensure we call FixupStaticTrampolines on all methods that are
852     // initialized.
853     class_linker_->MakeInitializedClassesVisiblyInitialized(self, /*wait=*/ true);
854 
855     ScopedObjectAccess soa(self);
856     UpdateMethodsPreFirstForkVisitor visitor(class_linker_);
857     class_linker_->VisitClasses(&visitor);
858   }
859   heap_->PreZygoteFork();
860   PreZygoteForkNativeBridge();
861 }
862 
PostZygoteFork()863 void Runtime::PostZygoteFork() {
864   jit::Jit* jit = GetJit();
865   if (jit != nullptr) {
866     jit->PostZygoteFork();
867     // Ensure that the threads in the JIT pool have been created with the right
868     // priority.
869     if (kIsDebugBuild && jit->GetThreadPool() != nullptr) {
870       jit->GetThreadPool()->CheckPthreadPriority(
871           IsZygote() ? jit->GetZygoteThreadPoolPthreadPriority()
872                      : jit->GetThreadPoolPthreadPriority());
873     }
874   }
875   // Reset all stats.
876   ResetStats(0xFFFFFFFF);
877 }
878 
CallExitHook(jint status)879 void Runtime::CallExitHook(jint status) {
880   if (exit_ != nullptr) {
881     ScopedThreadStateChange tsc(Thread::Current(), ThreadState::kNative);
882     exit_(status);
883     LOG(WARNING) << "Exit hook returned instead of exiting!";
884   }
885 }
886 
SweepSystemWeaks(IsMarkedVisitor * visitor)887 void Runtime::SweepSystemWeaks(IsMarkedVisitor* visitor) {
888   // Userfaultfd compaction updates weak intern-table page-by-page via
889   // LinearAlloc.
890   if (!GetHeap()->IsPerformingUffdCompaction()) {
891     GetInternTable()->SweepInternTableWeaks(visitor);
892   }
893   GetMonitorList()->SweepMonitorList(visitor);
894   GetJavaVM()->SweepJniWeakGlobals(visitor);
895   GetHeap()->SweepAllocationRecords(visitor);
896   // Sweep JIT tables only if the GC is moving as in other cases the entries are
897   // not updated.
898   if (GetJit() != nullptr && GetHeap()->IsMovingGc()) {
899     // Visit JIT literal tables. Objects in these tables are classes and strings
900     // and only classes can be affected by class unloading. The strings always
901     // stay alive as they are strongly interned.
902     // TODO: Move this closer to CleanupClassLoaders, to avoid blocking weak accesses
903     // from mutators. See b/32167580.
904     GetJit()->GetCodeCache()->SweepRootTables(visitor);
905   }
906 
907   // All other generic system-weak holders.
908   for (gc::AbstractSystemWeakHolder* holder : system_weak_holders_) {
909     holder->Sweep(visitor);
910   }
911 }
912 
ParseOptions(const RuntimeOptions & raw_options,bool ignore_unrecognized,RuntimeArgumentMap * runtime_options)913 bool Runtime::ParseOptions(const RuntimeOptions& raw_options,
914                            bool ignore_unrecognized,
915                            RuntimeArgumentMap* runtime_options) {
916   Locks::Init();
917   InitLogging(/* argv= */ nullptr, Abort);  // Calls Locks::Init() as a side effect.
918   bool parsed = ParsedOptions::Parse(raw_options, ignore_unrecognized, runtime_options);
919   if (!parsed) {
920     LOG(ERROR) << "Failed to parse options";
921     return false;
922   }
923   return true;
924 }
925 
926 // Callback to check whether it is safe to call Abort (e.g., to use a call to
927 // LOG(FATAL)).  It is only safe to call Abort if the runtime has been created,
928 // properly initialized, and has not shut down.
IsSafeToCallAbort()929 static bool IsSafeToCallAbort() NO_THREAD_SAFETY_ANALYSIS {
930   Runtime* runtime = Runtime::Current();
931   return runtime != nullptr && runtime->IsStarted() && !runtime->IsShuttingDownLocked();
932 }
933 
AddGeneratedCodeRange(const void * start,size_t size)934 void Runtime::AddGeneratedCodeRange(const void* start, size_t size) {
935   if (HandlesSignalsInCompiledCode()) {
936     fault_manager.AddGeneratedCodeRange(start, size);
937   }
938 }
939 
RemoveGeneratedCodeRange(const void * start,size_t size)940 void Runtime::RemoveGeneratedCodeRange(const void* start, size_t size) {
941   if (HandlesSignalsInCompiledCode()) {
942     fault_manager.RemoveGeneratedCodeRange(start, size);
943   }
944 }
945 
Create(RuntimeArgumentMap && runtime_options)946 bool Runtime::Create(RuntimeArgumentMap&& runtime_options) {
947   // TODO: acquire a static mutex on Runtime to avoid racing.
948   if (Runtime::instance_ != nullptr) {
949     return false;
950   }
951   instance_ = new Runtime;
952   Locks::SetClientCallback(IsSafeToCallAbort);
953   if (!instance_->Init(std::move(runtime_options))) {
954     // TODO: Currently deleting the instance will abort the runtime on destruction. Now This will
955     // leak memory, instead. Fix the destructor. b/19100793.
956     // delete instance_;
957     instance_ = nullptr;
958     return false;
959   }
960   return true;
961 }
962 
Create(const RuntimeOptions & raw_options,bool ignore_unrecognized)963 bool Runtime::Create(const RuntimeOptions& raw_options, bool ignore_unrecognized) {
964   RuntimeArgumentMap runtime_options;
965   return ParseOptions(raw_options, ignore_unrecognized, &runtime_options) &&
966       Create(std::move(runtime_options));
967 }
968 
CreateSystemClassLoader(Runtime * runtime)969 static jobject CreateSystemClassLoader(Runtime* runtime) {
970   if (runtime->IsAotCompiler() && !runtime->GetCompilerCallbacks()->IsBootImage()) {
971     return nullptr;
972   }
973 
974   ScopedObjectAccess soa(Thread::Current());
975   ClassLinker* cl = runtime->GetClassLinker();
976   auto pointer_size = cl->GetImagePointerSize();
977 
978   ObjPtr<mirror::Class> class_loader_class = GetClassRoot<mirror::ClassLoader>(cl);
979   DCHECK(class_loader_class->IsInitialized());  // Class roots have been initialized.
980 
981   ArtMethod* getSystemClassLoader = class_loader_class->FindClassMethod(
982       "getSystemClassLoader", "()Ljava/lang/ClassLoader;", pointer_size);
983   CHECK(getSystemClassLoader != nullptr);
984   CHECK(getSystemClassLoader->IsStatic());
985 
986   ObjPtr<mirror::Object> system_class_loader = getSystemClassLoader->InvokeStatic<'L'>(soa.Self());
987   CHECK(system_class_loader != nullptr)
988       << (soa.Self()->IsExceptionPending() ? soa.Self()->GetException()->Dump() : "<null>");
989 
990   ScopedAssertNoThreadSuspension sants(__FUNCTION__);
991   jobject g_system_class_loader =
992       runtime->GetJavaVM()->AddGlobalRef(soa.Self(), system_class_loader);
993   soa.Self()->SetClassLoaderOverride(g_system_class_loader);
994 
995   ObjPtr<mirror::Class> thread_class = WellKnownClasses::java_lang_Thread.Get();
996   ArtField* contextClassLoader =
997       thread_class->FindDeclaredInstanceField("contextClassLoader", "Ljava/lang/ClassLoader;");
998   CHECK(contextClassLoader != nullptr);
999 
1000   // We can't run in a transaction yet.
1001   contextClassLoader->SetObject<false>(soa.Self()->GetPeer(), system_class_loader);
1002 
1003   return g_system_class_loader;
1004 }
1005 
GetCompilerExecutable() const1006 std::string Runtime::GetCompilerExecutable() const {
1007   if (!compiler_executable_.empty()) {
1008     return compiler_executable_;
1009   }
1010   std::string compiler_executable = GetArtBinDir() + "/dex2oat";
1011   if (kIsDebugBuild) {
1012     compiler_executable += 'd';
1013   }
1014   if (kIsTargetBuild) {
1015     compiler_executable += Is64BitInstructionSet(kRuntimeISA) ? "64" : "32";
1016   }
1017   return compiler_executable;
1018 }
1019 
RunRootClinits(Thread * self)1020 void Runtime::RunRootClinits(Thread* self) {
1021   class_linker_->RunRootClinits(self);
1022 
1023   GcRoot<mirror::Throwable>* exceptions[] = {
1024       &pre_allocated_OutOfMemoryError_when_throwing_exception_,
1025       // &pre_allocated_OutOfMemoryError_when_throwing_oome_,             // Same class as above.
1026       // &pre_allocated_OutOfMemoryError_when_handling_stack_overflow_,   // Same class as above.
1027       &pre_allocated_NoClassDefFoundError_,
1028   };
1029   for (GcRoot<mirror::Throwable>* exception : exceptions) {
1030     StackHandleScope<1> hs(self);
1031     Handle<mirror::Class> klass = hs.NewHandle<mirror::Class>(exception->Read()->GetClass());
1032     class_linker_->EnsureInitialized(self, klass, true, true);
1033     self->AssertNoPendingException();
1034   }
1035 }
1036 
Start()1037 bool Runtime::Start() {
1038   VLOG(startup) << "Runtime::Start entering";
1039 
1040   CHECK(!no_sig_chain_) << "A started runtime should have sig chain enabled";
1041 
1042   // If a debug host build, disable ptrace restriction for debugging and test timeout thread dump.
1043   // Only 64-bit as prctl() may fail in 32 bit userspace on a 64-bit kernel.
1044 #if defined(__linux__) && !defined(ART_TARGET_ANDROID) && defined(__x86_64__)
1045   if (kIsDebugBuild) {
1046     if (prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY) != 0) {
1047       PLOG(WARNING) << "Failed setting PR_SET_PTRACER to PR_SET_PTRACER_ANY";
1048     }
1049   }
1050 #endif
1051 
1052   // Restore main thread state to kNative as expected by native code.
1053   Thread* self = Thread::Current();
1054 
1055   started_ = true;
1056 
1057   // Before running any clinit, set up the native methods provided by the runtime itself.
1058   RegisterRuntimeNativeMethods(self->GetJniEnv());
1059 
1060   class_linker_->RunEarlyRootClinits(self);
1061   InitializeIntrinsics();
1062 
1063   self->TransitionFromRunnableToSuspended(ThreadState::kNative);
1064 
1065   // InitNativeMethods needs to be after started_ so that the classes
1066   // it touches will have methods linked to the oat file if necessary.
1067   {
1068     ScopedTrace trace2("InitNativeMethods");
1069     InitNativeMethods();
1070   }
1071 
1072   // InitializeCorePlatformApiPrivateFields() needs to be called after well known class
1073   // initializtion in InitNativeMethods().
1074   art::hiddenapi::InitializeCorePlatformApiPrivateFields();
1075 
1076   // Initialize well known thread group values that may be accessed threads while attaching.
1077   InitThreadGroups(self);
1078 
1079   Thread::FinishStartup();
1080 
1081   // Create the JIT either if we have to use JIT compilation or save profiling info. This is
1082   // done after FinishStartup as the JIT pool needs Java thread peers, which require the main
1083   // ThreadGroup to exist.
1084   //
1085   // TODO(calin): We use the JIT class as a proxy for JIT compilation and for
1086   // recoding profiles. Maybe we should consider changing the name to be more clear it's
1087   // not only about compiling. b/28295073.
1088   if (jit_options_->UseJitCompilation() || jit_options_->GetSaveProfilingInfo()) {
1089     CreateJit();
1090 #ifdef ADDRESS_SANITIZER
1091     // (b/238730394): In older implementations of sanitizer + glibc there is a race between
1092     // pthread_create and dlopen that could cause a deadlock. pthread_create interceptor in ASAN
1093     // uses dl_pthread_iterator with a callback that could request a dl_load_lock via call to
1094     // __tls_get_addr [1]. dl_pthread_iterate would already hold dl_load_lock so this could cause a
1095     // deadlock. __tls_get_addr needs a dl_load_lock only when there is a dlopen happening in
1096     // parallel. As a workaround we wait for the pthread_create (i.e JIT thread pool creation) to
1097     // finish before going to the next phase. Creating a system class loader could need a dlopen so
1098     // we wait here till threads are initialized.
1099     // [1] https://github.com/llvm/llvm-project/blob/main/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp#L408
1100     // See this for more context: https://reviews.llvm.org/D98926
1101     // TODO(b/238730394): Revisit this workaround once we migrate to musl libc.
1102     if (jit_ != nullptr) {
1103       jit_->GetThreadPool()->WaitForWorkersToBeCreated();
1104     }
1105 #endif
1106   }
1107 
1108   // Send the start phase event. We have to wait till here as this is when the main thread peer
1109   // has just been generated, important root clinits have been run and JNI is completely functional.
1110   {
1111     ScopedObjectAccess soa(self);
1112     callbacks_->NextRuntimePhase(RuntimePhaseCallback::RuntimePhase::kStart);
1113   }
1114 
1115   system_class_loader_ = CreateSystemClassLoader(this);
1116 
1117   if (!is_zygote_) {
1118     if (is_native_bridge_loaded_) {
1119       PreInitializeNativeBridge(".");
1120     }
1121     NativeBridgeAction action = force_native_bridge_
1122         ? NativeBridgeAction::kInitialize
1123         : NativeBridgeAction::kUnload;
1124     InitNonZygoteOrPostFork(self->GetJniEnv(),
1125                             /* is_system_server= */ false,
1126                             /* is_child_zygote= */ false,
1127                             action,
1128                             GetInstructionSetString(kRuntimeISA));
1129   }
1130 
1131   {
1132     ScopedObjectAccess soa(self);
1133     StartDaemonThreads();
1134     self->GetJniEnv()->AssertLocalsEmpty();
1135 
1136     // Send the initialized phase event. Send it after starting the Daemon threads so that agents
1137     // cannot delay the daemon threads from starting forever.
1138     callbacks_->NextRuntimePhase(RuntimePhaseCallback::RuntimePhase::kInit);
1139     self->GetJniEnv()->AssertLocalsEmpty();
1140   }
1141 
1142   VLOG(startup) << "Runtime::Start exiting";
1143   finished_starting_ = true;
1144 
1145   if (trace_config_.get() != nullptr && trace_config_->trace_file != "") {
1146     ScopedThreadStateChange tsc(self, ThreadState::kWaitingForMethodTracingStart);
1147     int flags = 0;
1148     if (trace_config_->clock_source == TraceClockSource::kDual) {
1149       flags = Trace::TraceFlag::kTraceClockSourceWallClock |
1150               Trace::TraceFlag::kTraceClockSourceThreadCpu;
1151     } else if (trace_config_->clock_source == TraceClockSource::kWall) {
1152       flags = Trace::TraceFlag::kTraceClockSourceWallClock;
1153     } else if (TraceClockSource::kThreadCpu == trace_config_->clock_source) {
1154       flags = Trace::TraceFlag::kTraceClockSourceThreadCpu;
1155     } else {
1156       LOG(ERROR) << "Unexpected clock source";
1157     }
1158     Trace::Start(trace_config_->trace_file.c_str(),
1159                  static_cast<int>(trace_config_->trace_file_size),
1160                  flags,
1161                  trace_config_->trace_output_mode,
1162                  trace_config_->trace_mode,
1163                  0);
1164   }
1165 
1166   // In case we have a profile path passed as a command line argument,
1167   // register the current class path for profiling now. Note that we cannot do
1168   // this before we create the JIT and having it here is the most convenient way.
1169   // This is used when testing profiles with dalvikvm command as there is no
1170   // framework to register the dex files for profiling.
1171   if (jit_.get() != nullptr && jit_options_->GetSaveProfilingInfo() &&
1172       !jit_options_->GetProfileSaverOptions().GetProfilePath().empty()) {
1173     std::vector<std::string> dex_filenames;
1174     Split(class_path_string_, ':', &dex_filenames);
1175 
1176     // We pass "" as the package name because at this point we don't know it. It could be the
1177     // Zygote or it could be a dalvikvm cmd line execution. The package name will be re-set during
1178     // post-fork or during RegisterAppInfo.
1179     //
1180     // Also, it's ok to pass "" to the ref profile filename. It indicates we don't have
1181     // a reference profile.
1182     RegisterAppInfo(
1183         /*package_name=*/ "",
1184         dex_filenames,
1185         jit_options_->GetProfileSaverOptions().GetProfilePath(),
1186         /*ref_profile_filename=*/ "",
1187         kVMRuntimePrimaryApk);
1188   }
1189 
1190   return true;
1191 }
1192 
EndThreadBirth()1193 void Runtime::EndThreadBirth() REQUIRES(Locks::runtime_shutdown_lock_) {
1194   DCHECK_GT(threads_being_born_, 0U);
1195   threads_being_born_--;
1196   if (shutting_down_started_ && threads_being_born_ == 0) {
1197     shutdown_cond_->Broadcast(Thread::Current());
1198   }
1199 }
1200 
InitNonZygoteOrPostFork(JNIEnv * env,bool is_system_server,bool is_child_zygote,NativeBridgeAction action,const char * isa,bool profile_system_server)1201 void Runtime::InitNonZygoteOrPostFork(
1202     JNIEnv* env,
1203     bool is_system_server,
1204     // This is true when we are initializing a child-zygote. It requires
1205     // native bridge initialization to be able to run guest native code in
1206     // doPreload().
1207     bool is_child_zygote,
1208     NativeBridgeAction action,
1209     const char* isa,
1210     bool profile_system_server) {
1211   if (is_native_bridge_loaded_) {
1212     switch (action) {
1213       case NativeBridgeAction::kUnload:
1214         UnloadNativeBridge();
1215         is_native_bridge_loaded_ = false;
1216         break;
1217       case NativeBridgeAction::kInitialize:
1218         InitializeNativeBridge(env, isa);
1219         break;
1220     }
1221   }
1222 
1223   if (is_child_zygote) {
1224     // If creating a child-zygote we only initialize native bridge. The rest of
1225     // runtime post-fork logic would spin up threads for Binder and JDWP.
1226     // Instead, the Java side of the child process will call a static main in a
1227     // class specified by the parent.
1228     return;
1229   }
1230 
1231   DCHECK(!IsZygote());
1232 
1233   if (is_system_server) {
1234     // Register the system server code paths.
1235     // TODO: Ideally this should be done by the VMRuntime#RegisterAppInfo. However, right now
1236     // the method is only called when we set up the profile. It should be called all the time
1237     // (simillar to the apps). Once that's done this manual registration can be removed.
1238     const char* system_server_classpath = getenv("SYSTEMSERVERCLASSPATH");
1239     if (system_server_classpath == nullptr || (strlen(system_server_classpath) == 0)) {
1240       LOG(WARNING) << "System server class path not set";
1241     } else {
1242       std::vector<std::string> jars = android::base::Split(system_server_classpath, ":");
1243       app_info_.RegisterAppInfo("android",
1244                                 jars,
1245                                 /*profile_output_filename=*/ "",
1246                                 /*ref_profile_filename=*/ "",
1247                                 AppInfo::CodeType::kPrimaryApk);
1248     }
1249 
1250     // Set the system server package name to "android".
1251     // This is used to tell the difference between samples provided by system server
1252     // and samples generated by other apps when processing boot image profiles.
1253     SetProcessPackageName("android");
1254     if (profile_system_server) {
1255       jit_options_->SetWaitForJitNotificationsToSaveProfile(false);
1256       VLOG(profiler) << "Enabling system server profiles";
1257     }
1258   }
1259 
1260   // We only used the runtime thread pool for loading app images. However the
1261   // speed up that this brings in theory isn't there in practice b/328173302.
1262   static constexpr bool kUseRuntimeThreadPool = false;
1263   // Create the thread pools.
1264   // Avoid creating the runtime thread pool for system server since it will not be used and would
1265   // waste memory.
1266   if (!is_system_server && kUseRuntimeThreadPool) {
1267     ScopedTrace timing("CreateThreadPool");
1268     constexpr size_t kStackSize = 64 * KB;
1269     constexpr size_t kMaxRuntimeWorkers = 4u;
1270     const size_t num_workers =
1271         std::min(static_cast<size_t>(std::thread::hardware_concurrency()), kMaxRuntimeWorkers);
1272     MutexLock mu(Thread::Current(), *Locks::runtime_thread_pool_lock_);
1273     CHECK(thread_pool_ == nullptr);
1274     thread_pool_.reset(
1275         ThreadPool::Create("Runtime", num_workers, /*create_peers=*/false, kStackSize));
1276     thread_pool_->StartWorkers(Thread::Current());
1277   }
1278 
1279   // Reset the gc performance data and metrics at zygote fork so that the events from
1280   // before fork aren't attributed to an app.
1281   heap_->ResetGcPerformanceInfo();
1282   GetMetrics()->Reset();
1283 
1284   if (metrics_reporter_ != nullptr) {
1285     // Now that we know if we are an app or system server, reload the metrics reporter config
1286     // in case there are any difference.
1287     metrics::ReportingConfig metrics_config =
1288         metrics::ReportingConfig::FromFlags(is_system_server);
1289 
1290     metrics_reporter_->ReloadConfig(metrics_config);
1291 
1292     metrics::SessionData session_data{metrics::SessionData::CreateDefault()};
1293     // Start the session id from 1 to avoid clashes with the default value.
1294     // (better for debugability)
1295     session_data.session_id = GetRandomNumber<int64_t>(1, std::numeric_limits<int64_t>::max());
1296     // TODO: set session_data.compilation_reason and session_data.compiler_filter
1297     metrics_reporter_->MaybeStartBackgroundThread(session_data);
1298     // Also notify about any updates to the app info.
1299     metrics_reporter_->NotifyAppInfoUpdated(&app_info_);
1300   }
1301 
1302   StartSignalCatcher();
1303 
1304   ScopedObjectAccess soa(Thread::Current());
1305   if (IsPerfettoHprofEnabled() &&
1306       (Dbg::IsJdwpAllowed() || IsProfileable() || IsProfileableFromShell() || IsJavaDebuggable() ||
1307        Runtime::Current()->IsSystemServer())) {
1308     std::string err;
1309     ScopedTrace tr("perfetto_hprof init.");
1310     ScopedThreadSuspension sts(Thread::Current(), ThreadState::kNative);
1311     if (!EnsurePerfettoPlugin(&err)) {
1312       LOG(WARNING) << "Failed to load perfetto_hprof: " << err;
1313     }
1314   }
1315   if (IsPerfettoJavaHeapStackProfEnabled() &&
1316       (Dbg::IsJdwpAllowed() || IsProfileable() || IsProfileableFromShell() || IsJavaDebuggable() ||
1317        Runtime::Current()->IsSystemServer())) {
1318     // Marker used for dev tracing similar to above markers.
1319     ScopedTrace tr("perfetto_javaheapprof init.");
1320   }
1321   if (Runtime::Current()->IsSystemServer()) {
1322     std::string err;
1323     ScopedTrace tr("odrefresh and device stats logging");
1324     ScopedThreadSuspension sts(Thread::Current(), ThreadState::kNative);
1325     // Report stats if available. This should be moved into ART Services when they are ready.
1326     if (!odrefresh::UploadStatsIfAvailable(&err)) {
1327       LOG(WARNING) << "Failed to upload odrefresh metrics: " << err;
1328     }
1329     metrics::SetupCallbackForDeviceStatus();
1330   }
1331 
1332   if (LIKELY(automatically_set_jni_ids_indirection_) && CanSetJniIdType()) {
1333     if (IsJavaDebuggable()) {
1334       SetJniIdType(JniIdType::kIndices);
1335     } else {
1336       SetJniIdType(JniIdType::kPointer);
1337     }
1338   }
1339   ATraceIntegerValue(
1340       "profilebootclasspath",
1341       static_cast<int>(jit_options_->GetProfileSaverOptions().GetProfileBootClassPath()));
1342   // Start the JDWP thread. If the command-line debugger flags specified "suspend=y",
1343   // this will pause the runtime (in the internal debugger implementation), so we probably want
1344   // this to come last.
1345   GetRuntimeCallbacks()->StartDebugger();
1346 }
1347 
StartSignalCatcher()1348 void Runtime::StartSignalCatcher() {
1349   if (!is_zygote_) {
1350     signal_catcher_ = new SignalCatcher();
1351   }
1352 }
1353 
IsShuttingDown(Thread * self)1354 bool Runtime::IsShuttingDown(Thread* self) {
1355   MutexLock mu(self, *Locks::runtime_shutdown_lock_);
1356   return IsShuttingDownLocked();
1357 }
1358 
StartDaemonThreads()1359 void Runtime::StartDaemonThreads() {
1360   ScopedTrace trace(__FUNCTION__);
1361   VLOG(startup) << "Runtime::StartDaemonThreads entering";
1362 
1363   Thread* self = Thread::Current();
1364 
1365   DCHECK_EQ(self->GetState(), ThreadState::kRunnable);
1366 
1367   WellKnownClasses::java_lang_Daemons_start->InvokeStatic<'V'>(self);
1368   if (UNLIKELY(self->IsExceptionPending())) {
1369     LOG(FATAL) << "Error starting java.lang.Daemons: " << self->GetException()->Dump();
1370   }
1371 
1372   VLOG(startup) << "Runtime::StartDaemonThreads exiting";
1373 }
1374 
OpenBootDexFiles(ArrayRef<const std::string> dex_filenames,ArrayRef<const std::string> dex_locations,ArrayRef<File> dex_files,std::vector<std::unique_ptr<const DexFile>> * out_dex_files)1375 static size_t OpenBootDexFiles(ArrayRef<const std::string> dex_filenames,
1376                                ArrayRef<const std::string> dex_locations,
1377                                ArrayRef<File> dex_files,
1378                                std::vector<std::unique_ptr<const DexFile>>* out_dex_files) {
1379   DCHECK(out_dex_files != nullptr) << "OpenDexFiles: out-param is nullptr";
1380   size_t failure_count = 0;
1381   for (size_t i = 0; i < dex_filenames.size(); i++) {
1382     const char* dex_filename = dex_filenames[i].c_str();
1383     const char* dex_location = dex_locations[i].c_str();
1384     File noFile;
1385     File* file = i < dex_files.size() ? &dex_files[i] : &noFile;
1386     static constexpr bool kVerifyChecksum = true;
1387     std::string error_msg;
1388     if (!OS::FileExists(dex_filename) && file->IsValid()) {
1389       LOG(WARNING) << "Skipping non-existent dex file '" << dex_filename << "'";
1390       continue;
1391     }
1392     bool verify = Runtime::Current()->IsVerificationEnabled();
1393     ArtDexFileLoader dex_file_loader(dex_filename, file, dex_location);
1394     if (!dex_file_loader.Open(verify, kVerifyChecksum, &error_msg, out_dex_files)) {
1395       LOG(WARNING) << "Failed to open .dex from file '" << dex_filename << "' / fd " << file->Fd()
1396                    << ": " << error_msg;
1397       ++failure_count;
1398     }
1399     if (file->IsValid()) {
1400       bool close_ok = file->Close();
1401       DCHECK(close_ok) << dex_filename;
1402     }
1403   }
1404   return failure_count;
1405 }
1406 
SetSentinel(ObjPtr<mirror::Object> sentinel)1407 void Runtime::SetSentinel(ObjPtr<mirror::Object> sentinel) {
1408   CHECK(sentinel_.Read() == nullptr);
1409   CHECK(sentinel != nullptr);
1410   CHECK(!heap_->IsMovableObject(sentinel));
1411   sentinel_ = GcRoot<mirror::Object>(sentinel);
1412 }
1413 
GetSentinel()1414 GcRoot<mirror::Object> Runtime::GetSentinel() {
1415   return sentinel_;
1416 }
1417 
CreatePreAllocatedException(Thread * self,Runtime * runtime,GcRoot<mirror::Throwable> * exception,const char * exception_class_descriptor,const char * msg)1418 static inline void CreatePreAllocatedException(Thread* self,
1419                                                Runtime* runtime,
1420                                                GcRoot<mirror::Throwable>* exception,
1421                                                const char* exception_class_descriptor,
1422                                                const char* msg)
1423     REQUIRES_SHARED(Locks::mutator_lock_) {
1424   DCHECK_EQ(self, Thread::Current());
1425   ClassLinker* class_linker = runtime->GetClassLinker();
1426   // Allocate an object without initializing the class to allow non-trivial Throwable.<clinit>().
1427   ObjPtr<mirror::Class> klass = class_linker->FindSystemClass(self, exception_class_descriptor);
1428   CHECK(klass != nullptr);
1429   gc::AllocatorType allocator_type = runtime->GetHeap()->GetCurrentAllocator();
1430   ObjPtr<mirror::Throwable> exception_object = ObjPtr<mirror::Throwable>::DownCast(
1431       klass->Alloc(self, allocator_type));
1432   CHECK(exception_object != nullptr);
1433   *exception = GcRoot<mirror::Throwable>(exception_object);
1434   // Initialize the "detailMessage" field.
1435   ObjPtr<mirror::String> message = mirror::String::AllocFromModifiedUtf8(self, msg);
1436   CHECK(message != nullptr);
1437   ObjPtr<mirror::Class> throwable = GetClassRoot<mirror::Throwable>(class_linker);
1438   ArtField* detailMessageField =
1439       throwable->FindDeclaredInstanceField("detailMessage", "Ljava/lang/String;");
1440   CHECK(detailMessageField != nullptr);
1441   detailMessageField->SetObject</* kTransactionActive= */ false>(exception->Read(), message);
1442 }
1443 
GetApexVersions(ArrayRef<const std::string> boot_class_path_locations)1444 std::string Runtime::GetApexVersions(ArrayRef<const std::string> boot_class_path_locations) {
1445   std::vector<std::string_view> bcp_apexes;
1446   for (std::string_view jar : boot_class_path_locations) {
1447     std::string_view apex = ApexNameFromLocation(jar);
1448     if (!apex.empty()) {
1449       bcp_apexes.push_back(apex);
1450     }
1451   }
1452   static const char* kApexFileName = "/apex/apex-info-list.xml";
1453   // Start with empty markers.
1454   std::string empty_apex_versions(bcp_apexes.size(), '/');
1455   // When running on host or chroot, we just use empty markers.
1456   if (!kIsTargetBuild || !OS::FileExists(kApexFileName)) {
1457     return empty_apex_versions;
1458   }
1459 #ifdef ART_TARGET_ANDROID
1460   if (access(kApexFileName, R_OK) != 0) {
1461     PLOG(WARNING) << "Failed to read " << kApexFileName;
1462     return empty_apex_versions;
1463   }
1464   auto info_list = apex::readApexInfoList(kApexFileName);
1465   if (!info_list.has_value()) {
1466     LOG(WARNING) << "Failed to parse " << kApexFileName;
1467     return empty_apex_versions;
1468   }
1469 
1470   std::string result;
1471   std::map<std::string_view, const apex::ApexInfo*> apex_infos;
1472   for (const apex::ApexInfo& info : info_list->getApexInfo()) {
1473     if (info.getIsActive()) {
1474       apex_infos.emplace(info.getModuleName(), &info);
1475     }
1476   }
1477   for (const std::string_view& str : bcp_apexes) {
1478     auto info = apex_infos.find(str);
1479     if (info == apex_infos.end() || info->second->getIsFactory()) {
1480       result += '/';
1481     } else {
1482       // In case lastUpdateMillis field is populated in apex-info-list.xml, we
1483       // prefer to use it as version scheme. If the field is missing we
1484       // fallback to the version code of the APEX.
1485       uint64_t version = info->second->hasLastUpdateMillis()
1486           ? info->second->getLastUpdateMillis()
1487           : info->second->getVersionCode();
1488       android::base::StringAppendF(&result, "/%" PRIu64, version);
1489     }
1490   }
1491   return result;
1492 #else
1493   return empty_apex_versions;  // Not an Android build.
1494 #endif
1495 }
1496 
InitializeApexVersions()1497 void Runtime::InitializeApexVersions() {
1498   apex_versions_ =
1499       GetApexVersions(ArrayRef<const std::string>(Runtime::Current()->GetBootClassPathLocations()));
1500 }
1501 
ReloadAllFlags(const std::string & caller)1502 void Runtime::ReloadAllFlags(const std::string& caller) {
1503   FlagBase::ReloadAllFlags(caller);
1504 }
1505 
FileFdsToFileObjects(std::vector<int> && fds)1506 static std::vector<File> FileFdsToFileObjects(std::vector<int>&& fds) {
1507   std::vector<File> files;
1508   files.reserve(fds.size());
1509   for (int fd : fds) {
1510     files.push_back(File(fd, /*check_usage=*/false));
1511   }
1512   return files;
1513 }
1514 
GetThreadSuspendTimeout(const RuntimeArgumentMap * runtime_options)1515 inline static uint64_t GetThreadSuspendTimeout(const RuntimeArgumentMap* runtime_options) {
1516   auto suspend_timeout_opt = runtime_options->GetOptional(RuntimeArgumentMap::ThreadSuspendTimeout);
1517   return suspend_timeout_opt.has_value() ?
1518              suspend_timeout_opt.value().GetNanoseconds() :
1519              ThreadList::kDefaultThreadSuspendTimeout *
1520                  android::base::GetIntProperty("ro.hw_timeout_multiplier", 1);
1521 }
1522 
Init(RuntimeArgumentMap && runtime_options_in)1523 bool Runtime::Init(RuntimeArgumentMap&& runtime_options_in) {
1524   // (b/30160149): protect subprocesses from modifications to LD_LIBRARY_PATH, etc.
1525   // Take a snapshot of the environment at the time the runtime was created, for use by Exec, etc.
1526   env_snapshot_.TakeSnapshot();
1527 
1528 #ifdef ART_PAGE_SIZE_AGNOSTIC
1529   gPageSize.AllowAccess();
1530 #endif
1531 
1532   using Opt = RuntimeArgumentMap;
1533   Opt runtime_options(std::move(runtime_options_in));
1534   ScopedTrace trace(__FUNCTION__);
1535   CHECK_EQ(static_cast<size_t>(sysconf(_SC_PAGE_SIZE)), gPageSize);
1536 
1537   // Reload all the flags value (from system properties and device configs).
1538   ReloadAllFlags(__FUNCTION__);
1539 
1540   deny_art_apex_data_files_ = runtime_options.Exists(Opt::DenyArtApexDataFiles);
1541   if (deny_art_apex_data_files_) {
1542     // We will run slower without those files if the system has taken an ART APEX update.
1543     LOG(WARNING) << "ART APEX data files are untrusted.";
1544   }
1545 
1546   // Early override for logging output.
1547   if (runtime_options.Exists(Opt::UseStderrLogger)) {
1548     android::base::SetLogger(android::base::StderrLogger);
1549   }
1550 
1551   MemMap::Init();
1552 
1553   verifier_missing_kthrow_fatal_ = runtime_options.GetOrDefault(Opt::VerifierMissingKThrowFatal);
1554   force_java_zygote_fork_loop_ = runtime_options.GetOrDefault(Opt::ForceJavaZygoteForkLoop);
1555   perfetto_hprof_enabled_ = runtime_options.GetOrDefault(Opt::PerfettoHprof);
1556   perfetto_javaheapprof_enabled_ = runtime_options.GetOrDefault(Opt::PerfettoJavaHeapStackProf);
1557 
1558   // Try to reserve a dedicated fault page. This is allocated for clobbered registers and sentinels.
1559   // If we cannot reserve it, log a warning.
1560   // Note: We allocate this first to have a good chance of grabbing the page. The address (0xebad..)
1561   //       is out-of-the-way enough that it should not collide with boot image mapping.
1562   // Note: Don't request an error message. That will lead to a maps dump in the case of failure,
1563   //       leading to logspam.
1564   {
1565     const uintptr_t sentinel_addr =
1566         RoundDown(static_cast<uintptr_t>(Context::kBadGprBase), gPageSize);
1567     protected_fault_page_ = MemMap::MapAnonymous("Sentinel fault page",
1568                                                  reinterpret_cast<uint8_t*>(sentinel_addr),
1569                                                  gPageSize,
1570                                                  PROT_NONE,
1571                                                  /*low_4gb=*/ true,
1572                                                  /*reuse=*/ false,
1573                                                  /*reservation=*/ nullptr,
1574                                                  /*error_msg=*/ nullptr);
1575     if (!protected_fault_page_.IsValid()) {
1576       LOG(WARNING) << "Could not reserve sentinel fault page";
1577     } else if (reinterpret_cast<uintptr_t>(protected_fault_page_.Begin()) != sentinel_addr) {
1578       LOG(WARNING) << "Could not reserve sentinel fault page at the right address.";
1579       protected_fault_page_.Reset();
1580     }
1581   }
1582 
1583   VLOG(startup) << "Runtime::Init -verbose:startup enabled";
1584 
1585   QuasiAtomic::Startup();
1586 
1587   oat_file_manager_ = new OatFileManager();
1588 
1589   jni_id_manager_.reset(new jni::JniIdManager());
1590 
1591   Thread::SetSensitiveThreadHook(runtime_options.GetOrDefault(Opt::HookIsSensitiveThread));
1592   Monitor::Init(runtime_options.GetOrDefault(Opt::LockProfThreshold),
1593                 runtime_options.GetOrDefault(Opt::StackDumpLockProfThreshold));
1594 
1595   image_locations_ = runtime_options.ReleaseOrDefault(Opt::Image);
1596 
1597   SetInstructionSet(runtime_options.GetOrDefault(Opt::ImageInstructionSet));
1598   boot_class_path_ = runtime_options.ReleaseOrDefault(Opt::BootClassPath);
1599   boot_class_path_locations_ = runtime_options.ReleaseOrDefault(Opt::BootClassPathLocations);
1600   DCHECK(boot_class_path_locations_.empty() ||
1601          boot_class_path_locations_.size() == boot_class_path_.size());
1602   if (boot_class_path_.empty()) {
1603     LOG(ERROR) << "Boot classpath is empty";
1604     return false;
1605   }
1606 
1607   boot_class_path_files_ =
1608       FileFdsToFileObjects(runtime_options.ReleaseOrDefault(Opt::BootClassPathFds));
1609   if (!boot_class_path_files_.empty() && boot_class_path_files_.size() != boot_class_path_.size()) {
1610     LOG(ERROR) << "Number of FDs specified in -Xbootclasspathfds must match the number of JARs in "
1611                << "-Xbootclasspath.";
1612     return false;
1613   }
1614 
1615   boot_class_path_image_files_ =
1616       FileFdsToFileObjects(runtime_options.ReleaseOrDefault(Opt::BootClassPathImageFds));
1617   boot_class_path_vdex_files_ =
1618       FileFdsToFileObjects(runtime_options.ReleaseOrDefault(Opt::BootClassPathVdexFds));
1619   boot_class_path_oat_files_ =
1620       FileFdsToFileObjects(runtime_options.ReleaseOrDefault(Opt::BootClassPathOatFds));
1621   CHECK(boot_class_path_image_files_.empty() ||
1622         boot_class_path_image_files_.size() == boot_class_path_.size());
1623   CHECK(boot_class_path_vdex_files_.empty() ||
1624         boot_class_path_vdex_files_.size() == boot_class_path_.size());
1625   CHECK(boot_class_path_oat_files_.empty() ||
1626         boot_class_path_oat_files_.size() == boot_class_path_.size());
1627 
1628   class_path_string_ = runtime_options.ReleaseOrDefault(Opt::ClassPath);
1629   properties_ = runtime_options.ReleaseOrDefault(Opt::PropertiesList);
1630 
1631   compiler_callbacks_ = runtime_options.GetOrDefault(Opt::CompilerCallbacksPtr);
1632   must_relocate_ = runtime_options.GetOrDefault(Opt::Relocate);
1633   is_zygote_ = runtime_options.Exists(Opt::Zygote);
1634   is_primary_zygote_ = runtime_options.Exists(Opt::PrimaryZygote);
1635   is_explicit_gc_disabled_ = runtime_options.Exists(Opt::DisableExplicitGC);
1636   is_eagerly_release_explicit_gc_disabled_ =
1637       runtime_options.Exists(Opt::DisableEagerlyReleaseExplicitGC);
1638   image_dex2oat_enabled_ = runtime_options.GetOrDefault(Opt::ImageDex2Oat);
1639   dump_native_stack_on_sig_quit_ = runtime_options.GetOrDefault(Opt::DumpNativeStackOnSigQuit);
1640   allow_in_memory_compilation_ = runtime_options.Exists(Opt::AllowInMemoryCompilation);
1641 
1642   if (is_zygote_ || runtime_options.Exists(Opt::OnlyUseTrustedOatFiles)) {
1643     oat_file_manager_->SetOnlyUseTrustedOatFiles();
1644   }
1645 
1646   vfprintf_ = runtime_options.GetOrDefault(Opt::HookVfprintf);
1647   exit_ = runtime_options.GetOrDefault(Opt::HookExit);
1648   abort_ = runtime_options.GetOrDefault(Opt::HookAbort);
1649 
1650   default_stack_size_ = runtime_options.GetOrDefault(Opt::StackSize);
1651 
1652   compiler_executable_ = runtime_options.ReleaseOrDefault(Opt::Compiler);
1653   compiler_options_ = runtime_options.ReleaseOrDefault(Opt::CompilerOptions);
1654   for (const std::string& option : Runtime::Current()->GetCompilerOptions()) {
1655     if (option == "--debuggable") {
1656       SetRuntimeDebugState(RuntimeDebugState::kJavaDebuggableAtInit);
1657       break;
1658     }
1659   }
1660   image_compiler_options_ = runtime_options.ReleaseOrDefault(Opt::ImageCompilerOptions);
1661 
1662   finalizer_timeout_ms_ = runtime_options.GetOrDefault(Opt::FinalizerTimeoutMs);
1663   max_spins_before_thin_lock_inflation_ =
1664       runtime_options.GetOrDefault(Opt::MaxSpinsBeforeThinLockInflation);
1665 
1666   monitor_list_ = new MonitorList;
1667   monitor_pool_ = MonitorPool::Create();
1668   thread_list_ = new ThreadList(GetThreadSuspendTimeout(&runtime_options));
1669   intern_table_ = new InternTable;
1670 
1671   monitor_timeout_enable_ = runtime_options.GetOrDefault(Opt::MonitorTimeoutEnable);
1672   int monitor_timeout_ms = runtime_options.GetOrDefault(Opt::MonitorTimeout);
1673   if (monitor_timeout_ms < Monitor::kMonitorTimeoutMinMs) {
1674     LOG(WARNING) << "Monitor timeout too short: Increasing";
1675     monitor_timeout_ms = Monitor::kMonitorTimeoutMinMs;
1676   }
1677   if (monitor_timeout_ms >= Monitor::kMonitorTimeoutMaxMs) {
1678     LOG(WARNING) << "Monitor timeout too long: Decreasing";
1679     monitor_timeout_ms = Monitor::kMonitorTimeoutMaxMs - 1;
1680   }
1681   monitor_timeout_ns_ = MsToNs(monitor_timeout_ms);
1682 
1683   verify_ = runtime_options.GetOrDefault(Opt::Verify);
1684 
1685   target_sdk_version_ = runtime_options.GetOrDefault(Opt::TargetSdkVersion);
1686 
1687   // Set hidden API enforcement policy. The checks are disabled by default and
1688   // we only enable them if:
1689   // (a) runtime was started with a command line flag that enables the checks, or
1690   // (b) Zygote forked a new process that is not exempt (see ZygoteHooks).
1691   hidden_api_policy_ = runtime_options.GetOrDefault(Opt::HiddenApiPolicy);
1692   DCHECK_IMPLIES(is_zygote_, hidden_api_policy_ == hiddenapi::EnforcementPolicy::kDisabled);
1693 
1694   // Set core platform API enforcement policy. The checks are disabled by default and
1695   // can be enabled with a command line flag. AndroidRuntime will pass the flag if
1696   // a system property is set.
1697   core_platform_api_policy_ = runtime_options.GetOrDefault(Opt::CorePlatformApiPolicy);
1698   if (core_platform_api_policy_ != hiddenapi::EnforcementPolicy::kDisabled) {
1699     LOG(INFO) << "Core platform API reporting enabled, enforcing="
1700         << (core_platform_api_policy_ == hiddenapi::EnforcementPolicy::kEnabled ? "true" : "false");
1701   }
1702 
1703   // Dex2Oat's Runtime does not need the signal chain or the fault handler
1704   // and it passes the `NoSigChain` option to `Runtime` to indicate this.
1705   no_sig_chain_ = runtime_options.Exists(Opt::NoSigChain);
1706   force_native_bridge_ = runtime_options.Exists(Opt::ForceNativeBridge);
1707 
1708   Split(runtime_options.GetOrDefault(Opt::CpuAbiList), ',', &cpu_abilist_);
1709 
1710   fingerprint_ = runtime_options.ReleaseOrDefault(Opt::Fingerprint);
1711 
1712   if (runtime_options.GetOrDefault(Opt::Interpret)) {
1713     GetInstrumentation()->ForceInterpretOnly();
1714   }
1715 
1716   zygote_max_failed_boots_ = runtime_options.GetOrDefault(Opt::ZygoteMaxFailedBoots);
1717   experimental_flags_ = runtime_options.GetOrDefault(Opt::Experimental);
1718   is_low_memory_mode_ = runtime_options.Exists(Opt::LowMemoryMode);
1719   madvise_willneed_total_dex_size_ = runtime_options.GetOrDefault(Opt::MadviseWillNeedVdexFileSize);
1720   madvise_willneed_odex_filesize_ = runtime_options.GetOrDefault(Opt::MadviseWillNeedOdexFileSize);
1721   madvise_willneed_art_filesize_ = runtime_options.GetOrDefault(Opt::MadviseWillNeedArtFileSize);
1722 
1723   jni_ids_indirection_ = runtime_options.GetOrDefault(Opt::OpaqueJniIds);
1724   automatically_set_jni_ids_indirection_ =
1725       runtime_options.GetOrDefault(Opt::AutoPromoteOpaqueJniIds);
1726 
1727   plugins_ = runtime_options.ReleaseOrDefault(Opt::Plugins);
1728   agent_specs_ = runtime_options.ReleaseOrDefault(Opt::AgentPath);
1729   // TODO Add back in -agentlib
1730   // for (auto lib : runtime_options.ReleaseOrDefault(Opt::AgentLib)) {
1731   //   agents_.push_back(lib);
1732   // }
1733 
1734   float foreground_heap_growth_multiplier;
1735   if (is_low_memory_mode_ && !runtime_options.Exists(Opt::ForegroundHeapGrowthMultiplier)) {
1736     // If low memory mode, use 1.0 as the multiplier by default.
1737     foreground_heap_growth_multiplier = 1.0f;
1738   } else {
1739     // Extra added to the default heap growth multiplier for concurrent GC
1740     // compaction algorithms. This is done for historical reasons.
1741     // TODO: remove when we revisit heap configurations.
1742     foreground_heap_growth_multiplier =
1743         runtime_options.GetOrDefault(Opt::ForegroundHeapGrowthMultiplier) + 1.0f;
1744   }
1745   XGcOption xgc_option = runtime_options.GetOrDefault(Opt::GcOption);
1746 
1747   // Generational CC collection is currently only compatible with Baker read barriers.
1748   bool use_generational_cc = kUseBakerReadBarrier && xgc_option.generational_cc;
1749 
1750   // Cache the apex versions.
1751   InitializeApexVersions();
1752 
1753   BackgroundGcOption background_gc =
1754       gUseReadBarrier ? BackgroundGcOption(gc::kCollectorTypeCCBackground) :
1755                         (gUseUserfaultfd ? BackgroundGcOption(gc::kCollectorTypeCMCBackground) :
1756                                            runtime_options.GetOrDefault(Opt::BackgroundGc));
1757 
1758   heap_ = new gc::Heap(runtime_options.GetOrDefault(Opt::MemoryInitialSize),
1759                        runtime_options.GetOrDefault(Opt::HeapGrowthLimit),
1760                        runtime_options.GetOrDefault(Opt::HeapMinFree),
1761                        runtime_options.GetOrDefault(Opt::HeapMaxFree),
1762                        runtime_options.GetOrDefault(Opt::HeapTargetUtilization),
1763                        foreground_heap_growth_multiplier,
1764                        runtime_options.GetOrDefault(Opt::StopForNativeAllocs),
1765                        runtime_options.GetOrDefault(Opt::MemoryMaximumSize),
1766                        runtime_options.GetOrDefault(Opt::NonMovingSpaceCapacity),
1767                        GetBootClassPath(),
1768                        GetBootClassPathLocations(),
1769                        GetBootClassPathFiles(),
1770                        GetBootClassPathImageFiles(),
1771                        GetBootClassPathVdexFiles(),
1772                        GetBootClassPathOatFiles(),
1773                        image_locations_,
1774                        instruction_set_,
1775                        // Override the collector type to CC if the read barrier config.
1776                        gUseReadBarrier ? gc::kCollectorTypeCC : xgc_option.collector_type_,
1777                        background_gc,
1778                        runtime_options.GetOrDefault(Opt::LargeObjectSpace),
1779                        runtime_options.GetOrDefault(Opt::LargeObjectThreshold),
1780                        runtime_options.GetOrDefault(Opt::ParallelGCThreads),
1781                        runtime_options.GetOrDefault(Opt::ConcGCThreads),
1782                        runtime_options.Exists(Opt::LowMemoryMode),
1783                        runtime_options.GetOrDefault(Opt::LongPauseLogThreshold),
1784                        runtime_options.GetOrDefault(Opt::LongGCLogThreshold),
1785                        runtime_options.Exists(Opt::IgnoreMaxFootprint),
1786                        runtime_options.GetOrDefault(Opt::AlwaysLogExplicitGcs),
1787                        runtime_options.GetOrDefault(Opt::UseTLAB),
1788                        xgc_option.verify_pre_gc_heap_,
1789                        xgc_option.verify_pre_sweeping_heap_,
1790                        xgc_option.verify_post_gc_heap_,
1791                        xgc_option.verify_pre_gc_rosalloc_,
1792                        xgc_option.verify_pre_sweeping_rosalloc_,
1793                        xgc_option.verify_post_gc_rosalloc_,
1794                        xgc_option.gcstress_,
1795                        xgc_option.measure_,
1796                        runtime_options.GetOrDefault(Opt::EnableHSpaceCompactForOOM),
1797                        use_generational_cc,
1798                        runtime_options.GetOrDefault(Opt::HSpaceCompactForOOMMinIntervalsMs),
1799                        runtime_options.Exists(Opt::DumpRegionInfoBeforeGC),
1800                        runtime_options.Exists(Opt::DumpRegionInfoAfterGC));
1801 
1802   dump_gc_performance_on_shutdown_ = runtime_options.Exists(Opt::DumpGCPerformanceOnShutdown);
1803 
1804   bool has_explicit_jdwp_options = runtime_options.Get(Opt::JdwpOptions) != nullptr;
1805   jdwp_options_ = runtime_options.GetOrDefault(Opt::JdwpOptions);
1806   jdwp_provider_ = CanonicalizeJdwpProvider(runtime_options.GetOrDefault(Opt::JdwpProvider),
1807                                             IsJavaDebuggable());
1808   switch (jdwp_provider_) {
1809     case JdwpProvider::kNone: {
1810       VLOG(jdwp) << "Disabling all JDWP support.";
1811       if (!jdwp_options_.empty()) {
1812         bool has_transport = jdwp_options_.find("transport") != std::string::npos;
1813         std::string adb_connection_args =
1814             std::string("  -XjdwpProvider:adbconnection -XjdwpOptions:") + jdwp_options_;
1815         if (has_explicit_jdwp_options) {
1816           LOG(WARNING) << "Jdwp options given when jdwp is disabled! You probably want to enable "
1817                       << "jdwp with one of:" << std::endl
1818                       << "  -Xplugin:libopenjdkjvmti" << (kIsDebugBuild ? "d" : "") << ".so "
1819                       << "-agentpath:libjdwp.so=" << jdwp_options_ << std::endl
1820                       << (has_transport ? "" : adb_connection_args);
1821         }
1822       }
1823       break;
1824     }
1825     case JdwpProvider::kAdbConnection: {
1826       constexpr const char* plugin_name = kIsDebugBuild ? "libadbconnectiond.so"
1827                                                         : "libadbconnection.so";
1828       plugins_.push_back(Plugin::Create(plugin_name));
1829       break;
1830     }
1831     case JdwpProvider::kUnset: {
1832       LOG(FATAL) << "Illegal jdwp provider " << jdwp_provider_ << " was not filtered out!";
1833     }
1834   }
1835   callbacks_->AddThreadLifecycleCallback(Dbg::GetThreadLifecycleCallback());
1836 
1837   jit_options_.reset(jit::JitOptions::CreateFromRuntimeArguments(runtime_options));
1838   if (IsAotCompiler()) {
1839     // If we are already the compiler at this point, we must be dex2oat. Don't create the jit in
1840     // this case.
1841     // If runtime_options doesn't have UseJIT set to true then CreateFromRuntimeArguments returns
1842     // null and we don't create the jit.
1843     jit_options_->SetUseJitCompilation(false);
1844     jit_options_->SetSaveProfilingInfo(false);
1845   }
1846 
1847   // Use MemMap arena pool for jit, malloc otherwise. Malloc arenas are faster to allocate but
1848   // can't be trimmed as easily.
1849   const bool use_malloc = IsAotCompiler();
1850   if (use_malloc) {
1851     arena_pool_.reset(new MallocArenaPool());
1852     jit_arena_pool_.reset(new MallocArenaPool());
1853   } else {
1854     arena_pool_.reset(new MemMapArenaPool(/* low_4gb= */ false));
1855     jit_arena_pool_.reset(new MemMapArenaPool(/* low_4gb= */ false, "CompilerMetadata"));
1856   }
1857 
1858   // For 64 bit compilers, it needs to be in low 4GB in the case where we are cross compiling for a
1859   // 32 bit target. In this case, we have 32 bit pointers in the dex cache arrays which can't hold
1860   // when we have 64 bit ArtMethod pointers.
1861   const bool low_4gb = IsAotCompiler() && Is64BitInstructionSet(kRuntimeISA);
1862   if (gUseUserfaultfd) {
1863     linear_alloc_arena_pool_.reset(new GcVisitedArenaPool(low_4gb, IsZygote()));
1864   } else if (low_4gb) {
1865     linear_alloc_arena_pool_.reset(new MemMapArenaPool(low_4gb));
1866   }
1867   linear_alloc_.reset(CreateLinearAlloc());
1868   startup_linear_alloc_.store(CreateLinearAlloc(), std::memory_order_relaxed);
1869 
1870   small_lrt_allocator_ = new jni::SmallLrtAllocator();
1871 
1872   BlockSignals();
1873   InitPlatformSignalHandlers();
1874 
1875   // Change the implicit checks flags based on runtime architecture.
1876   switch (kRuntimeISA) {
1877     case InstructionSet::kArm64:
1878       implicit_suspend_checks_ = true;
1879       FALLTHROUGH_INTENDED;
1880     case InstructionSet::kArm:
1881     case InstructionSet::kThumb2:
1882     case InstructionSet::kRiscv64:
1883     case InstructionSet::kX86:
1884     case InstructionSet::kX86_64:
1885       implicit_null_checks_ = true;
1886       // Historical note: Installing stack protection was not playing well with Valgrind.
1887       implicit_so_checks_ = true;
1888       break;
1889     default:
1890       // Keep the defaults.
1891       break;
1892   }
1893 
1894   fault_manager.Init(!no_sig_chain_);
1895   if (!no_sig_chain_) {
1896     if (HandlesSignalsInCompiledCode()) {
1897       // These need to be in a specific order.  The null point check handler must be
1898       // after the suspend check and stack overflow check handlers.
1899       //
1900       // Note: the instances attach themselves to the fault manager and are handled by it. The
1901       //       manager will delete the instance on Shutdown().
1902       if (implicit_suspend_checks_) {
1903         new SuspensionHandler(&fault_manager);
1904       }
1905 
1906       if (implicit_so_checks_) {
1907         new StackOverflowHandler(&fault_manager);
1908       }
1909 
1910       if (implicit_null_checks_) {
1911         new NullPointerHandler(&fault_manager);
1912       }
1913 
1914       if (kEnableJavaStackTraceHandler) {
1915         new JavaStackTraceHandler(&fault_manager);
1916       }
1917 
1918       if (interpreter::CanRuntimeUseNterp()) {
1919         // Nterp code can use signal handling just like the compiled managed code.
1920         OatQuickMethodHeader* nterp_header = OatQuickMethodHeader::NterpMethodHeader;
1921         fault_manager.AddGeneratedCodeRange(nterp_header->GetCode(), nterp_header->GetCodeSize());
1922       }
1923     }
1924   }
1925 
1926   verifier_logging_threshold_ms_ = runtime_options.GetOrDefault(Opt::VerifierLoggingThreshold);
1927 
1928   std::string error_msg;
1929   java_vm_ = JavaVMExt::Create(this, runtime_options, &error_msg);
1930   if (java_vm_.get() == nullptr) {
1931     LOG(ERROR) << "Could not initialize JavaVMExt: " << error_msg;
1932     return false;
1933   }
1934 
1935   // Add the JniEnv handler.
1936   // TODO Refactor this stuff.
1937   java_vm_->AddEnvironmentHook(JNIEnvExt::GetEnvHandler);
1938 
1939   Thread::Startup();
1940 
1941   // ClassLinker needs an attached thread, but we can't fully attach a thread without creating
1942   // objects. We can't supply a thread group yet; it will be fixed later. Since we are the main
1943   // thread, we do not get a java peer.
1944   Thread* self = Thread::Attach("main", false, nullptr, false, /* should_run_callbacks= */ true);
1945   CHECK_EQ(self->GetThreadId(), ThreadList::kMainThreadId);
1946   CHECK(self != nullptr);
1947 
1948   self->SetIsRuntimeThread(IsAotCompiler());
1949 
1950   // Set us to runnable so tools using a runtime can allocate and GC by default
1951   self->TransitionFromSuspendedToRunnable();
1952 
1953   // Now we're attached, we can take the heap locks and validate the heap.
1954   GetHeap()->EnableObjectValidation();
1955 
1956   CHECK_GE(GetHeap()->GetContinuousSpaces().size(), 1U);
1957 
1958   if (UNLIKELY(IsAotCompiler())) {
1959     class_linker_ = new AotClassLinker(intern_table_);
1960   } else {
1961     class_linker_ = new ClassLinker(
1962         intern_table_,
1963         runtime_options.GetOrDefault(Opt::FastClassNotFoundException));
1964   }
1965   if (GetHeap()->HasBootImageSpace()) {
1966     bool result = class_linker_->InitFromBootImage(&error_msg);
1967     if (!result) {
1968       LOG(ERROR) << "Could not initialize from image: " << error_msg;
1969       return false;
1970     }
1971     if (kIsDebugBuild) {
1972       for (auto image_space : GetHeap()->GetBootImageSpaces()) {
1973         image_space->VerifyImageAllocations();
1974       }
1975     }
1976     {
1977       ScopedTrace trace2("AddImageStringsToTable");
1978       for (gc::space::ImageSpace* image_space : heap_->GetBootImageSpaces()) {
1979         GetInternTable()->AddImageStringsToTable(image_space, VoidFunctor());
1980       }
1981     }
1982 
1983     const size_t total_components = gc::space::ImageSpace::GetNumberOfComponents(
1984         ArrayRef<gc::space::ImageSpace* const>(heap_->GetBootImageSpaces()));
1985     if (total_components != GetBootClassPath().size()) {
1986       // The boot image did not contain all boot class path components. Load the rest.
1987       CHECK_LT(total_components, GetBootClassPath().size());
1988       size_t start = total_components;
1989       DCHECK_LT(start, GetBootClassPath().size());
1990       std::vector<std::unique_ptr<const DexFile>> extra_boot_class_path;
1991       if (runtime_options.Exists(Opt::BootClassPathDexList)) {
1992         extra_boot_class_path.swap(*runtime_options.GetOrDefault(Opt::BootClassPathDexList));
1993       } else {
1994         ArrayRef<File> bcp_files = start < GetBootClassPathFiles().size() ?
1995                                        ArrayRef<File>(GetBootClassPathFiles()).SubArray(start) :
1996                                        ArrayRef<File>();
1997         OpenBootDexFiles(ArrayRef<const std::string>(GetBootClassPath()).SubArray(start),
1998                          ArrayRef<const std::string>(GetBootClassPathLocations()).SubArray(start),
1999                          bcp_files,
2000                          &extra_boot_class_path);
2001       }
2002       class_linker_->AddExtraBootDexFiles(self, std::move(extra_boot_class_path));
2003     }
2004     if (IsJavaDebuggable() || jit_options_->GetProfileSaverOptions().GetProfileBootClassPath()) {
2005       // Deoptimize the boot image if debuggable  as the code may have been compiled non-debuggable.
2006       // Also deoptimize if we are profiling the boot class path.
2007       ScopedThreadSuspension sts(self, ThreadState::kNative);
2008       ScopedSuspendAll ssa(__FUNCTION__);
2009       DeoptimizeBootImage();
2010     }
2011   } else {
2012     std::vector<std::unique_ptr<const DexFile>> boot_class_path;
2013     if (runtime_options.Exists(Opt::BootClassPathDexList)) {
2014       boot_class_path.swap(*runtime_options.GetOrDefault(Opt::BootClassPathDexList));
2015     } else {
2016       OpenBootDexFiles(ArrayRef<const std::string>(GetBootClassPath()),
2017                        ArrayRef<const std::string>(GetBootClassPathLocations()),
2018                        ArrayRef<File>(GetBootClassPathFiles()),
2019                        &boot_class_path);
2020     }
2021     if (!class_linker_->InitWithoutImage(std::move(boot_class_path), &error_msg)) {
2022       LOG(ERROR) << "Could not initialize without image: " << error_msg;
2023       return false;
2024     }
2025 
2026     // TODO: Should we move the following to InitWithoutImage?
2027     SetInstructionSet(instruction_set_);
2028     for (uint32_t i = 0; i < kCalleeSaveSize; i++) {
2029       CalleeSaveType type = CalleeSaveType(i);
2030       if (!HasCalleeSaveMethod(type)) {
2031         SetCalleeSaveMethod(CreateCalleeSaveMethod(), type);
2032       }
2033     }
2034   }
2035 
2036   // Now that the boot image space is set, cache the boot classpath checksums,
2037   // to be used when validating oat files.
2038   ArrayRef<gc::space::ImageSpace* const> image_spaces(GetHeap()->GetBootImageSpaces());
2039   ArrayRef<const DexFile* const> bcp_dex_files(GetClassLinker()->GetBootClassPath());
2040   boot_class_path_checksums_ = gc::space::ImageSpace::GetBootClassPathChecksums(image_spaces,
2041                                                                                 bcp_dex_files);
2042 
2043   CHECK(class_linker_ != nullptr);
2044 
2045   if (runtime_options.Exists(Opt::MethodTrace)) {
2046     trace_config_.reset(new TraceConfig());
2047     trace_config_->trace_file = runtime_options.ReleaseOrDefault(Opt::MethodTraceFile);
2048     trace_config_->trace_file_size = runtime_options.ReleaseOrDefault(Opt::MethodTraceFileSize);
2049     trace_config_->trace_mode = Trace::TraceMode::kMethodTracing;
2050     trace_config_->trace_output_mode = runtime_options.Exists(Opt::MethodTraceStreaming) ?
2051                                            TraceOutputMode::kStreaming :
2052                                            TraceOutputMode::kFile;
2053     trace_config_->clock_source = runtime_options.GetOrDefault(Opt::MethodTraceClock);
2054   }
2055 
2056   // TODO: Remove this in a follow up CL. This isn't used anywhere.
2057   Trace::SetDefaultClockSource(runtime_options.GetOrDefault(Opt::ProfileClock));
2058 
2059   if (GetHeap()->HasBootImageSpace()) {
2060     const ImageHeader& image_header = GetHeap()->GetBootImageSpaces()[0]->GetImageHeader();
2061     ObjPtr<mirror::ObjectArray<mirror::Object>> boot_image_live_objects =
2062         ObjPtr<mirror::ObjectArray<mirror::Object>>::DownCast(
2063             image_header.GetImageRoot(ImageHeader::kBootImageLiveObjects));
2064     pre_allocated_OutOfMemoryError_when_throwing_exception_ = GcRoot<mirror::Throwable>(
2065         boot_image_live_objects->Get(ImageHeader::kOomeWhenThrowingException)->AsThrowable());
2066     DCHECK(pre_allocated_OutOfMemoryError_when_throwing_exception_.Read()->GetClass()
2067                ->DescriptorEquals("Ljava/lang/OutOfMemoryError;"));
2068     pre_allocated_OutOfMemoryError_when_throwing_oome_ = GcRoot<mirror::Throwable>(
2069         boot_image_live_objects->Get(ImageHeader::kOomeWhenThrowingOome)->AsThrowable());
2070     DCHECK(pre_allocated_OutOfMemoryError_when_throwing_oome_.Read()->GetClass()
2071                ->DescriptorEquals("Ljava/lang/OutOfMemoryError;"));
2072     pre_allocated_OutOfMemoryError_when_handling_stack_overflow_ = GcRoot<mirror::Throwable>(
2073         boot_image_live_objects->Get(ImageHeader::kOomeWhenHandlingStackOverflow)->AsThrowable());
2074     DCHECK(pre_allocated_OutOfMemoryError_when_handling_stack_overflow_.Read()->GetClass()
2075                ->DescriptorEquals("Ljava/lang/OutOfMemoryError;"));
2076     pre_allocated_NoClassDefFoundError_ = GcRoot<mirror::Throwable>(
2077         boot_image_live_objects->Get(ImageHeader::kNoClassDefFoundError)->AsThrowable());
2078     DCHECK(pre_allocated_NoClassDefFoundError_.Read()->GetClass()
2079                ->DescriptorEquals("Ljava/lang/NoClassDefFoundError;"));
2080   } else {
2081     // Pre-allocate an OutOfMemoryError for the case when we fail to
2082     // allocate the exception to be thrown.
2083     CreatePreAllocatedException(self,
2084                                 this,
2085                                 &pre_allocated_OutOfMemoryError_when_throwing_exception_,
2086                                 "Ljava/lang/OutOfMemoryError;",
2087                                 "OutOfMemoryError thrown while trying to throw an exception; "
2088                                     "no stack trace available");
2089     // Pre-allocate an OutOfMemoryError for the double-OOME case.
2090     CreatePreAllocatedException(self,
2091                                 this,
2092                                 &pre_allocated_OutOfMemoryError_when_throwing_oome_,
2093                                 "Ljava/lang/OutOfMemoryError;",
2094                                 "OutOfMemoryError thrown while trying to throw OutOfMemoryError; "
2095                                     "no stack trace available");
2096     // Pre-allocate an OutOfMemoryError for the case when we fail to
2097     // allocate while handling a stack overflow.
2098     CreatePreAllocatedException(self,
2099                                 this,
2100                                 &pre_allocated_OutOfMemoryError_when_handling_stack_overflow_,
2101                                 "Ljava/lang/OutOfMemoryError;",
2102                                 "OutOfMemoryError thrown while trying to handle a stack overflow; "
2103                                     "no stack trace available");
2104 
2105     // Pre-allocate a NoClassDefFoundError for the common case of failing to find a system class
2106     // ahead of checking the application's class loader.
2107     CreatePreAllocatedException(self,
2108                                 this,
2109                                 &pre_allocated_NoClassDefFoundError_,
2110                                 "Ljava/lang/NoClassDefFoundError;",
2111                                 "Class not found using the boot class loader; "
2112                                     "no stack trace available");
2113   }
2114 
2115   // Class-roots are setup, we can now finish initializing the JniIdManager.
2116   GetJniIdManager()->Init(self);
2117 
2118   InitMetrics();
2119 
2120   // Runtime initialization is largely done now.
2121   // We load plugins first since that can modify the runtime state slightly.
2122   // Load all plugins
2123   {
2124     // The init method of plugins expect the state of the thread to be non runnable.
2125     ScopedThreadSuspension sts(self, ThreadState::kNative);
2126     for (auto& plugin : plugins_) {
2127       std::string err;
2128       if (!plugin.Load(&err)) {
2129         LOG(FATAL) << plugin << " failed to load: " << err;
2130       }
2131     }
2132   }
2133 
2134   // Look for a native bridge.
2135   //
2136   // The intended flow here is, in the case of a running system:
2137   //
2138   // Runtime::Init() (zygote):
2139   //   LoadNativeBridge -> dlopen from cmd line parameter.
2140   //  |
2141   //  V
2142   // Runtime::Start() (zygote):
2143   //   No-op wrt native bridge.
2144   //  |
2145   //  | start app
2146   //  V
2147   // DidForkFromZygote(action)
2148   //   action = kUnload -> dlclose native bridge.
2149   //   action = kInitialize -> initialize library
2150   //
2151   //
2152   // The intended flow here is, in the case of a simple dalvikvm call:
2153   //
2154   // Runtime::Init():
2155   //   LoadNativeBridge -> dlopen from cmd line parameter.
2156   //  |
2157   //  V
2158   // Runtime::Start():
2159   //   DidForkFromZygote(kInitialize) -> try to initialize any native bridge given.
2160   //   No-op wrt native bridge.
2161   {
2162     std::string native_bridge_file_name = runtime_options.ReleaseOrDefault(Opt::NativeBridge);
2163     is_native_bridge_loaded_ = LoadNativeBridge(native_bridge_file_name);
2164   }
2165 
2166   // Startup agents
2167   // TODO Maybe we should start a new thread to run these on. Investigate RI behavior more.
2168   for (auto& agent_spec : agent_specs_) {
2169     // TODO Check err
2170     int res = 0;
2171     std::string err = "";
2172     ti::LoadError error;
2173     std::unique_ptr<ti::Agent> agent = agent_spec.Load(&res, &error, &err);
2174 
2175     if (agent != nullptr) {
2176       agents_.push_back(std::move(agent));
2177       continue;
2178     }
2179 
2180     switch (error) {
2181       case ti::LoadError::kInitializationError:
2182         LOG(FATAL) << "Unable to initialize agent!";
2183         UNREACHABLE();
2184 
2185       case ti::LoadError::kLoadingError:
2186         LOG(ERROR) << "Unable to load an agent: " << err;
2187         continue;
2188 
2189       case ti::LoadError::kNoError:
2190         break;
2191     }
2192     LOG(FATAL) << "Unreachable";
2193     UNREACHABLE();
2194   }
2195   {
2196     ScopedObjectAccess soa(self);
2197     callbacks_->NextRuntimePhase(RuntimePhaseCallback::RuntimePhase::kInitialAgents);
2198   }
2199 
2200   if (IsZygote() && IsPerfettoHprofEnabled()) {
2201     constexpr const char* plugin_name = kIsDebugBuild ?
2202         "libperfetto_hprofd.so" : "libperfetto_hprof.so";
2203     // Load eagerly in Zygote to improve app startup times. This will make
2204     // subsequent dlopens for the library no-ops.
2205     dlopen(plugin_name, RTLD_NOW | RTLD_LOCAL);
2206   }
2207 
2208   VLOG(startup) << "Runtime::Init exiting";
2209 
2210   return true;
2211 }
2212 
InitMetrics()2213 void Runtime::InitMetrics() {
2214   metrics::ReportingConfig metrics_config = metrics::ReportingConfig::FromFlags();
2215   metrics_reporter_ = metrics::MetricsReporter::Create(metrics_config, this);
2216 }
2217 
RequestMetricsReport(bool synchronous)2218 void Runtime::RequestMetricsReport(bool synchronous) {
2219   if (metrics_reporter_) {
2220     metrics_reporter_->RequestMetricsReport(synchronous);
2221   }
2222 }
2223 
EnsurePluginLoaded(const char * plugin_name,std::string * error_msg)2224 bool Runtime::EnsurePluginLoaded(const char* plugin_name, std::string* error_msg) {
2225   // Is the plugin already loaded?
2226   for (const Plugin& p : plugins_) {
2227     if (p.GetLibrary() == plugin_name) {
2228       return true;
2229     }
2230   }
2231   Plugin new_plugin = Plugin::Create(plugin_name);
2232 
2233   if (!new_plugin.Load(error_msg)) {
2234     return false;
2235   }
2236   plugins_.push_back(std::move(new_plugin));
2237   return true;
2238 }
2239 
EnsurePerfettoPlugin(std::string * error_msg)2240 bool Runtime::EnsurePerfettoPlugin(std::string* error_msg) {
2241   constexpr const char* plugin_name = kIsDebugBuild ?
2242     "libperfetto_hprofd.so" : "libperfetto_hprof.so";
2243   return EnsurePluginLoaded(plugin_name, error_msg);
2244 }
2245 
EnsureJvmtiPlugin(Runtime * runtime,std::string * error_msg)2246 static bool EnsureJvmtiPlugin(Runtime* runtime,
2247                               std::string* error_msg) {
2248   // TODO Rename Dbg::IsJdwpAllowed is IsDebuggingAllowed.
2249   DCHECK(Dbg::IsJdwpAllowed() || !runtime->IsJavaDebuggable())
2250       << "Being debuggable requires that jdwp (i.e. debugging) is allowed.";
2251   // Is the process debuggable? Otherwise, do not attempt to load the plugin unless we are
2252   // specifically allowed.
2253   if (!Dbg::IsJdwpAllowed()) {
2254     *error_msg = "Process is not allowed to load openjdkjvmti plugin. Process must be debuggable";
2255     return false;
2256   }
2257 
2258   constexpr const char* plugin_name = kIsDebugBuild ? "libopenjdkjvmtid.so" : "libopenjdkjvmti.so";
2259   return runtime->EnsurePluginLoaded(plugin_name, error_msg);
2260 }
2261 
2262 // Attach a new agent and add it to the list of runtime agents
2263 //
2264 // TODO: once we decide on the threading model for agents,
2265 //   revisit this and make sure we're doing this on the right thread
2266 //   (and we synchronize access to any shared data structures like "agents_")
2267 //
AttachAgent(JNIEnv * env,const std::string & agent_arg,jobject class_loader)2268 void Runtime::AttachAgent(JNIEnv* env, const std::string& agent_arg, jobject class_loader) {
2269   std::string error_msg;
2270   if (!EnsureJvmtiPlugin(this, &error_msg)) {
2271     LOG(WARNING) << "Could not load plugin: " << error_msg;
2272     ScopedObjectAccess soa(Thread::Current());
2273     ThrowIOException("%s", error_msg.c_str());
2274     return;
2275   }
2276 
2277   ti::AgentSpec agent_spec(agent_arg);
2278 
2279   int res = 0;
2280   ti::LoadError error;
2281   std::unique_ptr<ti::Agent> agent = agent_spec.Attach(env, class_loader, &res, &error, &error_msg);
2282 
2283   if (agent != nullptr) {
2284     agents_.push_back(std::move(agent));
2285   } else {
2286     LOG(WARNING) << "Agent attach failed (result=" << error << ") : " << error_msg;
2287     ScopedObjectAccess soa(Thread::Current());
2288     ThrowIOException("%s", error_msg.c_str());
2289   }
2290 }
2291 
InitNativeMethods()2292 void Runtime::InitNativeMethods() {
2293   VLOG(startup) << "Runtime::InitNativeMethods entering";
2294   Thread* self = Thread::Current();
2295   JNIEnv* env = self->GetJniEnv();
2296 
2297   // Must be in the kNative state for calling native methods (JNI_OnLoad code).
2298   CHECK_EQ(self->GetState(), ThreadState::kNative);
2299 
2300   // Then set up libjavacore / libopenjdk / libicu_jni ,which are just
2301   // a regular JNI libraries with a regular JNI_OnLoad. Most JNI libraries can
2302   // just use System.loadLibrary, but libcore can't because it's the library
2303   // that implements System.loadLibrary!
2304   //
2305   // By setting calling class to java.lang.Object, the caller location for these
2306   // JNI libs is core-oj.jar in the ART APEX, and hence they are loaded from the
2307   // com_android_art linker namespace.
2308   jclass java_lang_Object;
2309   {
2310     // Use global JNI reference to keep the local references empty. If we allocated a
2311     // local reference here, the `PushLocalFrame(128)` that these internal libraries do
2312     // in their `JNI_OnLoad()` would reserve a lot of unnecessary space due to rounding.
2313     ScopedObjectAccess soa(self);
2314     java_lang_Object = reinterpret_cast<jclass>(
2315         GetJavaVM()->AddGlobalRef(self, GetClassRoot<mirror::Object>(GetClassLinker())));
2316   }
2317 
2318   // libicu_jni has to be initialized before libopenjdk{d} due to runtime dependency from
2319   // libopenjdk{d} to Icu4cMetadata native methods in libicu_jni. See http://b/143888405
2320   {
2321     std::string error_msg;
2322     if (!java_vm_->LoadNativeLibrary(
2323           env, "libicu_jni.so", nullptr, java_lang_Object, &error_msg)) {
2324       LOG(FATAL) << "LoadNativeLibrary failed for \"libicu_jni.so\": " << error_msg;
2325     }
2326   }
2327   {
2328     std::string error_msg;
2329     if (!java_vm_->LoadNativeLibrary(
2330           env, "libjavacore.so", nullptr, java_lang_Object, &error_msg)) {
2331       LOG(FATAL) << "LoadNativeLibrary failed for \"libjavacore.so\": " << error_msg;
2332     }
2333   }
2334   {
2335     constexpr const char* kOpenJdkLibrary = kIsDebugBuild
2336                                                 ? "libopenjdkd.so"
2337                                                 : "libopenjdk.so";
2338     std::string error_msg;
2339     if (!java_vm_->LoadNativeLibrary(
2340           env, kOpenJdkLibrary, nullptr, java_lang_Object, &error_msg)) {
2341       LOG(FATAL) << "LoadNativeLibrary failed for \"" << kOpenJdkLibrary << "\": " << error_msg;
2342     }
2343   }
2344   env->DeleteGlobalRef(java_lang_Object);
2345 
2346   // Initialize well known classes that may invoke runtime native methods.
2347   WellKnownClasses::LateInit(env);
2348 
2349   VLOG(startup) << "Runtime::InitNativeMethods exiting";
2350 }
2351 
ReclaimArenaPoolMemory()2352 void Runtime::ReclaimArenaPoolMemory() {
2353   arena_pool_->LockReclaimMemory();
2354 }
2355 
InitThreadGroups(Thread * self)2356 void Runtime::InitThreadGroups(Thread* self) {
2357   ScopedObjectAccess soa(self);
2358   ArtField* main_thread_group_field = WellKnownClasses::java_lang_ThreadGroup_mainThreadGroup;
2359   ArtField* system_thread_group_field = WellKnownClasses::java_lang_ThreadGroup_systemThreadGroup;
2360   // Note: This is running before `ClassLinker::RunRootClinits()`, so we cannot rely on
2361   // `ThreadGroup` and `Thread` being initialized.
2362   // TODO: Clean up initialization order after all well-known methods are converted to `ArtMethod*`
2363   // (and therefore the `WellKnownClasses::Init()` shall not initialize any classes).
2364   StackHandleScope<2u> hs(self);
2365   Handle<mirror::Class> thread_group_class =
2366       hs.NewHandle(main_thread_group_field->GetDeclaringClass());
2367   bool initialized = GetClassLinker()->EnsureInitialized(
2368       self, thread_group_class, /*can_init_fields=*/ true, /*can_init_parents=*/ true);
2369   CHECK(initialized);
2370   Handle<mirror::Class> thread_class = hs.NewHandle(WellKnownClasses::java_lang_Thread.Get());
2371   initialized = GetClassLinker()->EnsureInitialized(
2372       self, thread_class, /*can_init_fields=*/ true, /*can_init_parents=*/ true);
2373   CHECK(initialized);
2374   main_thread_group_ =
2375       soa.Vm()->AddGlobalRef(self, main_thread_group_field->GetObject(thread_group_class.Get()));
2376   CHECK_IMPLIES(main_thread_group_ == nullptr, IsAotCompiler());
2377   system_thread_group_ =
2378       soa.Vm()->AddGlobalRef(self, system_thread_group_field->GetObject(thread_group_class.Get()));
2379   CHECK_IMPLIES(system_thread_group_ == nullptr, IsAotCompiler());
2380 }
2381 
GetMainThreadGroup() const2382 jobject Runtime::GetMainThreadGroup() const {
2383   CHECK_IMPLIES(main_thread_group_ == nullptr, IsAotCompiler());
2384   return main_thread_group_;
2385 }
2386 
GetSystemThreadGroup() const2387 jobject Runtime::GetSystemThreadGroup() const {
2388   CHECK_IMPLIES(system_thread_group_ == nullptr, IsAotCompiler());
2389   return system_thread_group_;
2390 }
2391 
GetSystemClassLoader() const2392 jobject Runtime::GetSystemClassLoader() const {
2393   CHECK_IMPLIES(system_class_loader_ == nullptr, IsAotCompiler());
2394   return system_class_loader_;
2395 }
2396 
RegisterRuntimeNativeMethods(JNIEnv * env)2397 void Runtime::RegisterRuntimeNativeMethods(JNIEnv* env) {
2398   register_dalvik_system_DexFile(env);
2399   register_dalvik_system_BaseDexClassLoader(env);
2400   register_dalvik_system_VMDebug(env);
2401   real_register_dalvik_system_VMRuntime(env);
2402   register_dalvik_system_VMStack(env);
2403   register_dalvik_system_ZygoteHooks(env);
2404   register_java_lang_Class(env);
2405   register_java_lang_Object(env);
2406   register_java_lang_invoke_MethodHandle(env);
2407   register_java_lang_invoke_MethodHandleImpl(env);
2408   register_java_lang_ref_FinalizerReference(env);
2409   register_java_lang_reflect_Array(env);
2410   register_java_lang_reflect_Constructor(env);
2411   register_java_lang_reflect_Executable(env);
2412   register_java_lang_reflect_Field(env);
2413   register_java_lang_reflect_Method(env);
2414   register_java_lang_reflect_Parameter(env);
2415   register_java_lang_reflect_Proxy(env);
2416   register_java_lang_ref_Reference(env);
2417   register_java_lang_StackStreamFactory(env);
2418   register_java_lang_String(env);
2419   register_java_lang_StringFactory(env);
2420   register_java_lang_System(env);
2421   register_java_lang_Thread(env);
2422   register_java_lang_Throwable(env);
2423   register_java_lang_VMClassLoader(env);
2424   register_java_util_concurrent_atomic_AtomicLong(env);
2425   register_jdk_internal_misc_Unsafe(env);
2426   register_libcore_io_Memory(env);
2427   register_libcore_util_CharsetUtils(env);
2428   register_org_apache_harmony_dalvik_ddmc_DdmServer(env);
2429   register_org_apache_harmony_dalvik_ddmc_DdmVmInternal(env);
2430   register_sun_misc_Unsafe(env);
2431 }
2432 
operator <<(std::ostream & os,const DeoptimizationKind & kind)2433 std::ostream& operator<<(std::ostream& os, const DeoptimizationKind& kind) {
2434   os << GetDeoptimizationKindName(kind);
2435   return os;
2436 }
2437 
DumpDeoptimizations(std::ostream & os)2438 void Runtime::DumpDeoptimizations(std::ostream& os) {
2439   for (size_t i = 0; i <= static_cast<size_t>(DeoptimizationKind::kLast); ++i) {
2440     if (deoptimization_counts_[i] != 0) {
2441       os << "Number of "
2442          << GetDeoptimizationKindName(static_cast<DeoptimizationKind>(i))
2443          << " deoptimizations: "
2444          << deoptimization_counts_[i]
2445          << "\n";
2446     }
2447   }
2448 }
2449 
SiqQuitNanoTime() const2450 std::optional<uint64_t> Runtime::SiqQuitNanoTime() const {
2451   return signal_catcher_ != nullptr ? signal_catcher_->SiqQuitNanoTime() : std::nullopt;
2452 }
2453 
DumpForSigQuit(std::ostream & os)2454 void Runtime::DumpForSigQuit(std::ostream& os) {
2455   // Print backtraces first since they are important do diagnose ANRs,
2456   // and ANRs can often be trimmed to limit upload size.
2457   thread_list_->DumpForSigQuit(os);
2458   GetClassLinker()->DumpForSigQuit(os);
2459   GetInternTable()->DumpForSigQuit(os);
2460   GetJavaVM()->DumpForSigQuit(os);
2461   GetHeap()->DumpForSigQuit(os);
2462   oat_file_manager_->DumpForSigQuit(os);
2463   if (GetJit() != nullptr) {
2464     GetJit()->DumpForSigQuit(os);
2465   } else {
2466     os << "Running non JIT\n";
2467   }
2468   DumpDeoptimizations(os);
2469   TrackedAllocators::Dump(os);
2470   GetMetrics()->DumpForSigQuit(os);
2471   os << "\n";
2472 
2473   BaseMutex::DumpAll(os);
2474 
2475   // Inform anyone else who is interested in SigQuit.
2476   {
2477     ScopedObjectAccess soa(Thread::Current());
2478     callbacks_->SigQuit();
2479   }
2480 }
2481 
DumpLockHolders(std::ostream & os)2482 void Runtime::DumpLockHolders(std::ostream& os) {
2483   pid_t mutator_lock_owner = Locks::mutator_lock_->GetExclusiveOwnerTid();
2484   pid_t thread_list_lock_owner = GetThreadList()->GetLockOwner();
2485   pid_t classes_lock_owner = GetClassLinker()->GetClassesLockOwner();
2486   pid_t dex_lock_owner = GetClassLinker()->GetDexLockOwner();
2487   if ((mutator_lock_owner | thread_list_lock_owner | classes_lock_owner | dex_lock_owner) != 0) {
2488     os << "Mutator lock exclusive owner tid: " << mutator_lock_owner << "\n"
2489        << "ThreadList lock owner tid: " << thread_list_lock_owner << "\n"
2490        << "ClassLinker classes lock owner tid: " << classes_lock_owner << "\n"
2491        << "ClassLinker dex lock owner tid: " << dex_lock_owner << "\n";
2492   }
2493 }
2494 
SetStatsEnabled(bool new_state)2495 void Runtime::SetStatsEnabled(bool new_state) {
2496   Thread* self = Thread::Current();
2497   MutexLock mu(self, *Locks::instrument_entrypoints_lock_);
2498   if (new_state == true) {
2499     GetStats()->Clear(~0);
2500     // TODO: wouldn't it make more sense to clear _all_ threads' stats?
2501     self->GetStats()->Clear(~0);
2502     if (stats_enabled_ != new_state) {
2503       GetInstrumentation()->InstrumentQuickAllocEntryPointsLocked();
2504     }
2505   } else if (stats_enabled_ != new_state) {
2506     GetInstrumentation()->UninstrumentQuickAllocEntryPointsLocked();
2507   }
2508   stats_enabled_ = new_state;
2509 }
2510 
ResetStats(int kinds)2511 void Runtime::ResetStats(int kinds) {
2512   GetStats()->Clear(kinds & 0xffff);
2513   // TODO: wouldn't it make more sense to clear _all_ threads' stats?
2514   Thread::Current()->GetStats()->Clear(kinds >> 16);
2515 }
2516 
GetStat(int kind)2517 uint64_t Runtime::GetStat(int kind) {
2518   RuntimeStats* stats;
2519   if (kind < (1<<16)) {
2520     stats = GetStats();
2521   } else {
2522     stats = Thread::Current()->GetStats();
2523     kind >>= 16;
2524   }
2525   switch (kind) {
2526   case KIND_ALLOCATED_OBJECTS:
2527     return stats->allocated_objects;
2528   case KIND_ALLOCATED_BYTES:
2529     return stats->allocated_bytes;
2530   case KIND_FREED_OBJECTS:
2531     return stats->freed_objects;
2532   case KIND_FREED_BYTES:
2533     return stats->freed_bytes;
2534   case KIND_GC_INVOCATIONS:
2535     return stats->gc_for_alloc_count;
2536   case KIND_CLASS_INIT_COUNT:
2537     return stats->class_init_count;
2538   case KIND_CLASS_INIT_TIME:
2539     return stats->class_init_time_ns;
2540   case KIND_EXT_ALLOCATED_OBJECTS:
2541   case KIND_EXT_ALLOCATED_BYTES:
2542   case KIND_EXT_FREED_OBJECTS:
2543   case KIND_EXT_FREED_BYTES:
2544     return 0;  // backward compatibility
2545   default:
2546     LOG(FATAL) << "Unknown statistic " << kind;
2547     UNREACHABLE();
2548   }
2549 }
2550 
BlockSignals()2551 void Runtime::BlockSignals() {
2552   SignalSet signals;
2553   signals.Add(SIGPIPE);
2554   // SIGQUIT is used to dump the runtime's state (including stack traces).
2555   signals.Add(SIGQUIT);
2556   // SIGUSR1 is used to initiate a GC.
2557   signals.Add(SIGUSR1);
2558   signals.Block();
2559 }
2560 
AttachCurrentThread(const char * thread_name,bool as_daemon,jobject thread_group,bool create_peer,bool should_run_callbacks)2561 bool Runtime::AttachCurrentThread(const char* thread_name, bool as_daemon, jobject thread_group,
2562                                   bool create_peer, bool should_run_callbacks) {
2563   ScopedTrace trace(__FUNCTION__);
2564   Thread* self = Thread::Attach(thread_name,
2565                                 as_daemon,
2566                                 thread_group,
2567                                 create_peer,
2568                                 should_run_callbacks);
2569   // Run ThreadGroup.add to notify the group that this thread is now started.
2570   if (self != nullptr && create_peer && !IsAotCompiler()) {
2571     ScopedObjectAccess soa(self);
2572     self->NotifyThreadGroup(soa, thread_group);
2573   }
2574   return self != nullptr;
2575 }
2576 
DetachCurrentThread(bool should_run_callbacks)2577 void Runtime::DetachCurrentThread(bool should_run_callbacks) {
2578   ScopedTrace trace(__FUNCTION__);
2579   Thread* self = Thread::Current();
2580   if (self == nullptr) {
2581     LOG(FATAL) << "attempting to detach thread that is not attached";
2582   }
2583   if (self->HasManagedStack()) {
2584     LOG(FATAL) << *Thread::Current() << " attempting to detach while still running code";
2585   }
2586   thread_list_->Unregister(self, should_run_callbacks);
2587 }
2588 
GetPreAllocatedOutOfMemoryErrorWhenThrowingException()2589 mirror::Throwable* Runtime::GetPreAllocatedOutOfMemoryErrorWhenThrowingException() {
2590   mirror::Throwable* oome = pre_allocated_OutOfMemoryError_when_throwing_exception_.Read();
2591   if (oome == nullptr) {
2592     LOG(ERROR) << "Failed to return pre-allocated OOME-when-throwing-exception";
2593   }
2594   return oome;
2595 }
2596 
GetPreAllocatedOutOfMemoryErrorWhenThrowingOOME()2597 mirror::Throwable* Runtime::GetPreAllocatedOutOfMemoryErrorWhenThrowingOOME() {
2598   mirror::Throwable* oome = pre_allocated_OutOfMemoryError_when_throwing_oome_.Read();
2599   if (oome == nullptr) {
2600     LOG(ERROR) << "Failed to return pre-allocated OOME-when-throwing-OOME";
2601   }
2602   return oome;
2603 }
2604 
GetPreAllocatedOutOfMemoryErrorWhenHandlingStackOverflow()2605 mirror::Throwable* Runtime::GetPreAllocatedOutOfMemoryErrorWhenHandlingStackOverflow() {
2606   mirror::Throwable* oome = pre_allocated_OutOfMemoryError_when_handling_stack_overflow_.Read();
2607   if (oome == nullptr) {
2608     LOG(ERROR) << "Failed to return pre-allocated OOME-when-handling-stack-overflow";
2609   }
2610   return oome;
2611 }
2612 
GetPreAllocatedNoClassDefFoundError()2613 mirror::Throwable* Runtime::GetPreAllocatedNoClassDefFoundError() {
2614   mirror::Throwable* ncdfe = pre_allocated_NoClassDefFoundError_.Read();
2615   if (ncdfe == nullptr) {
2616     LOG(ERROR) << "Failed to return pre-allocated NoClassDefFoundError";
2617   }
2618   return ncdfe;
2619 }
2620 
VisitConstantRoots(RootVisitor * visitor)2621 void Runtime::VisitConstantRoots(RootVisitor* visitor) {
2622   // Visiting the roots of these ArtMethods is not currently required since all the GcRoots are
2623   // null.
2624   BufferedRootVisitor<16> buffered_visitor(visitor, RootInfo(kRootVMInternal));
2625   const PointerSize pointer_size = GetClassLinker()->GetImagePointerSize();
2626   if (HasResolutionMethod()) {
2627     resolution_method_->VisitRoots(buffered_visitor, pointer_size);
2628   }
2629   if (HasImtConflictMethod()) {
2630     imt_conflict_method_->VisitRoots(buffered_visitor, pointer_size);
2631   }
2632   if (imt_unimplemented_method_ != nullptr) {
2633     imt_unimplemented_method_->VisitRoots(buffered_visitor, pointer_size);
2634   }
2635   for (uint32_t i = 0; i < kCalleeSaveSize; ++i) {
2636     auto* m = reinterpret_cast<ArtMethod*>(callee_save_methods_[i]);
2637     if (m != nullptr) {
2638       m->VisitRoots(buffered_visitor, pointer_size);
2639     }
2640   }
2641 }
2642 
VisitConcurrentRoots(RootVisitor * visitor,VisitRootFlags flags)2643 void Runtime::VisitConcurrentRoots(RootVisitor* visitor, VisitRootFlags flags) {
2644   // Userfaultfd compaction updates intern-tables and class-tables page-by-page
2645   // via LinearAlloc. So don't visit them here.
2646   if (GetHeap()->IsPerformingUffdCompaction()) {
2647     class_linker_->VisitRoots(visitor, flags, /*visit_class_roots=*/false);
2648   } else {
2649     intern_table_->VisitRoots(visitor, flags);
2650     class_linker_->VisitRoots(visitor, flags, /*visit_class_roots=*/true);
2651   }
2652   jni_id_manager_->VisitRoots(visitor);
2653   heap_->VisitAllocationRecords(visitor);
2654   if (jit_ != nullptr) {
2655     jit_->VisitRoots(visitor);
2656   }
2657   if ((flags & kVisitRootFlagNewRoots) == 0) {
2658     // Guaranteed to have no new roots in the constant roots.
2659     VisitConstantRoots(visitor);
2660   }
2661 }
2662 
VisitNonThreadRoots(RootVisitor * visitor)2663 void Runtime::VisitNonThreadRoots(RootVisitor* visitor) {
2664   java_vm_->VisitRoots(visitor);
2665   sentinel_.VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal));
2666   pre_allocated_OutOfMemoryError_when_throwing_exception_
2667       .VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal));
2668   pre_allocated_OutOfMemoryError_when_throwing_oome_
2669       .VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal));
2670   pre_allocated_OutOfMemoryError_when_handling_stack_overflow_
2671       .VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal));
2672   pre_allocated_NoClassDefFoundError_.VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal));
2673   VisitImageRoots(visitor);
2674   class_linker_->VisitTransactionRoots(visitor);
2675 }
2676 
VisitNonConcurrentRoots(RootVisitor * visitor,VisitRootFlags flags)2677 void Runtime::VisitNonConcurrentRoots(RootVisitor* visitor, VisitRootFlags flags) {
2678   VisitThreadRoots(visitor, flags);
2679   VisitNonThreadRoots(visitor);
2680 }
2681 
VisitThreadRoots(RootVisitor * visitor,VisitRootFlags flags)2682 void Runtime::VisitThreadRoots(RootVisitor* visitor, VisitRootFlags flags) {
2683   thread_list_->VisitRoots(visitor, flags);
2684 }
2685 
VisitRoots(RootVisitor * visitor,VisitRootFlags flags)2686 void Runtime::VisitRoots(RootVisitor* visitor, VisitRootFlags flags) {
2687   VisitNonConcurrentRoots(visitor, flags);
2688   VisitConcurrentRoots(visitor, flags);
2689 }
2690 
VisitReflectiveTargets(ReflectiveValueVisitor * visitor)2691 void Runtime::VisitReflectiveTargets(ReflectiveValueVisitor *visitor) {
2692   thread_list_->VisitReflectiveTargets(visitor);
2693   heap_->VisitReflectiveTargets(visitor);
2694   jni_id_manager_->VisitReflectiveTargets(visitor);
2695   callbacks_->VisitReflectiveTargets(visitor);
2696 }
2697 
VisitImageRoots(RootVisitor * visitor)2698 void Runtime::VisitImageRoots(RootVisitor* visitor) {
2699   // We only confirm that image roots are unchanged.
2700   if (kIsDebugBuild) {
2701     for (auto* space : GetHeap()->GetContinuousSpaces()) {
2702       if (space->IsImageSpace()) {
2703         auto* image_space = space->AsImageSpace();
2704         const auto& image_header = image_space->GetImageHeader();
2705         for (int32_t i = 0, size = image_header.GetImageRoots()->GetLength(); i != size; ++i) {
2706           mirror::Object* obj =
2707               image_header.GetImageRoot(static_cast<ImageHeader::ImageRoot>(i)).Ptr();
2708           if (obj != nullptr) {
2709             mirror::Object* after_obj = obj;
2710             visitor->VisitRoot(&after_obj, RootInfo(kRootStickyClass));
2711             CHECK_EQ(after_obj, obj);
2712           }
2713         }
2714       }
2715     }
2716   }
2717 }
2718 
CreateRuntimeMethod(ClassLinker * class_linker,LinearAlloc * linear_alloc)2719 static ArtMethod* CreateRuntimeMethod(ClassLinker* class_linker, LinearAlloc* linear_alloc)
2720     REQUIRES_SHARED(Locks::mutator_lock_) {
2721   const PointerSize image_pointer_size = class_linker->GetImagePointerSize();
2722   const size_t method_alignment = ArtMethod::Alignment(image_pointer_size);
2723   const size_t method_size = ArtMethod::Size(image_pointer_size);
2724   LengthPrefixedArray<ArtMethod>* method_array = class_linker->AllocArtMethodArray(
2725       Thread::Current(),
2726       linear_alloc,
2727       1);
2728   ArtMethod* method = &method_array->At(0, method_size, method_alignment);
2729   CHECK(method != nullptr);
2730   method->SetDexMethodIndex(dex::kDexNoIndex);
2731   CHECK(method->IsRuntimeMethod());
2732   return method;
2733 }
2734 
CreateImtConflictMethod(LinearAlloc * linear_alloc)2735 ArtMethod* Runtime::CreateImtConflictMethod(LinearAlloc* linear_alloc) {
2736   ClassLinker* const class_linker = GetClassLinker();
2737   ArtMethod* method = CreateRuntimeMethod(class_linker, linear_alloc);
2738   // When compiling, the code pointer will get set later when the image is loaded.
2739   const PointerSize pointer_size = GetInstructionSetPointerSize(instruction_set_);
2740   if (IsAotCompiler()) {
2741     method->SetEntryPointFromQuickCompiledCodePtrSize(nullptr, pointer_size);
2742   } else {
2743     method->SetEntryPointFromQuickCompiledCode(GetQuickImtConflictStub());
2744   }
2745   // Create empty conflict table.
2746   method->SetImtConflictTable(class_linker->CreateImtConflictTable(/*count=*/0u, linear_alloc),
2747                               pointer_size);
2748   return method;
2749 }
2750 
SetImtConflictMethod(ArtMethod * method)2751 void Runtime::SetImtConflictMethod(ArtMethod* method) {
2752   CHECK(method != nullptr);
2753   CHECK(method->IsRuntimeMethod());
2754   imt_conflict_method_ = method;
2755 }
2756 
CreateResolutionMethod()2757 ArtMethod* Runtime::CreateResolutionMethod() {
2758   auto* method = CreateRuntimeMethod(GetClassLinker(), GetLinearAlloc());
2759   // When compiling, the code pointer will get set later when the image is loaded.
2760   if (IsAotCompiler()) {
2761     PointerSize pointer_size = GetInstructionSetPointerSize(instruction_set_);
2762     method->SetEntryPointFromQuickCompiledCodePtrSize(nullptr, pointer_size);
2763     method->SetEntryPointFromJniPtrSize(nullptr, pointer_size);
2764   } else {
2765     method->SetEntryPointFromQuickCompiledCode(GetQuickResolutionStub());
2766     method->SetEntryPointFromJni(GetJniDlsymLookupCriticalStub());
2767   }
2768   return method;
2769 }
2770 
CreateCalleeSaveMethod()2771 ArtMethod* Runtime::CreateCalleeSaveMethod() {
2772   auto* method = CreateRuntimeMethod(GetClassLinker(), GetLinearAlloc());
2773   PointerSize pointer_size = GetInstructionSetPointerSize(instruction_set_);
2774   method->SetEntryPointFromQuickCompiledCodePtrSize(nullptr, pointer_size);
2775   DCHECK_NE(instruction_set_, InstructionSet::kNone);
2776   DCHECK(method->IsRuntimeMethod());
2777   return method;
2778 }
2779 
DisallowNewSystemWeaks()2780 void Runtime::DisallowNewSystemWeaks() {
2781   CHECK(!gUseReadBarrier);
2782   monitor_list_->DisallowNewMonitors();
2783   intern_table_->ChangeWeakRootState(gc::kWeakRootStateNoReadsOrWrites);
2784   java_vm_->DisallowNewWeakGlobals();
2785   heap_->DisallowNewAllocationRecords();
2786   if (GetJit() != nullptr) {
2787     GetJit()->GetCodeCache()->DisallowInlineCacheAccess();
2788   }
2789 
2790   // All other generic system-weak holders.
2791   for (gc::AbstractSystemWeakHolder* holder : system_weak_holders_) {
2792     holder->Disallow();
2793   }
2794 }
2795 
AllowNewSystemWeaks()2796 void Runtime::AllowNewSystemWeaks() {
2797   CHECK(!gUseReadBarrier);
2798   monitor_list_->AllowNewMonitors();
2799   intern_table_->ChangeWeakRootState(gc::kWeakRootStateNormal);  // TODO: Do this in the sweeping.
2800   java_vm_->AllowNewWeakGlobals();
2801   heap_->AllowNewAllocationRecords();
2802   if (GetJit() != nullptr) {
2803     GetJit()->GetCodeCache()->AllowInlineCacheAccess();
2804   }
2805 
2806   // All other generic system-weak holders.
2807   for (gc::AbstractSystemWeakHolder* holder : system_weak_holders_) {
2808     holder->Allow();
2809   }
2810 }
2811 
BroadcastForNewSystemWeaks(bool broadcast_for_checkpoint)2812 void Runtime::BroadcastForNewSystemWeaks(bool broadcast_for_checkpoint) {
2813   // This is used for the read barrier case that uses the thread-local
2814   // Thread::GetWeakRefAccessEnabled() flag and the checkpoint while weak ref access is disabled
2815   // (see ThreadList::RunCheckpoint).
2816   monitor_list_->BroadcastForNewMonitors();
2817   intern_table_->BroadcastForNewInterns();
2818   java_vm_->BroadcastForNewWeakGlobals();
2819   heap_->BroadcastForNewAllocationRecords();
2820   if (GetJit() != nullptr) {
2821     GetJit()->GetCodeCache()->BroadcastForInlineCacheAccess();
2822   }
2823 
2824   // All other generic system-weak holders.
2825   for (gc::AbstractSystemWeakHolder* holder : system_weak_holders_) {
2826     holder->Broadcast(broadcast_for_checkpoint);
2827   }
2828 }
2829 
SetInstructionSet(InstructionSet instruction_set)2830 void Runtime::SetInstructionSet(InstructionSet instruction_set) {
2831   instruction_set_ = instruction_set;
2832   switch (instruction_set) {
2833     case InstructionSet::kThumb2:
2834       // kThumb2 is the same as kArm, use the canonical value.
2835       instruction_set_ = InstructionSet::kArm;
2836       break;
2837     case InstructionSet::kArm:
2838     case InstructionSet::kArm64:
2839     case InstructionSet::kRiscv64:
2840     case InstructionSet::kX86:
2841     case InstructionSet::kX86_64:
2842       break;
2843     default:
2844       UNIMPLEMENTED(FATAL) << instruction_set_;
2845       UNREACHABLE();
2846   }
2847 }
2848 
ClearInstructionSet()2849 void Runtime::ClearInstructionSet() {
2850   instruction_set_ = InstructionSet::kNone;
2851 }
2852 
SetCalleeSaveMethod(ArtMethod * method,CalleeSaveType type)2853 void Runtime::SetCalleeSaveMethod(ArtMethod* method, CalleeSaveType type) {
2854   DCHECK_LT(static_cast<uint32_t>(type), kCalleeSaveSize);
2855   CHECK(method != nullptr);
2856   callee_save_methods_[static_cast<size_t>(type)] = reinterpret_cast<uintptr_t>(method);
2857 }
2858 
ClearCalleeSaveMethods()2859 void Runtime::ClearCalleeSaveMethods() {
2860   for (size_t i = 0; i < kCalleeSaveSize; ++i) {
2861     callee_save_methods_[i] = reinterpret_cast<uintptr_t>(nullptr);
2862   }
2863 }
2864 
RegisterAppInfo(const std::string & package_name,const std::vector<std::string> & code_paths,const std::string & profile_output_filename,const std::string & ref_profile_filename,int32_t code_type)2865 void Runtime::RegisterAppInfo(const std::string& package_name,
2866                               const std::vector<std::string>& code_paths,
2867                               const std::string& profile_output_filename,
2868                               const std::string& ref_profile_filename,
2869                               int32_t code_type) {
2870   app_info_.RegisterAppInfo(
2871       package_name,
2872       code_paths,
2873       profile_output_filename,
2874       ref_profile_filename,
2875       AppInfo::FromVMRuntimeConstants(code_type));
2876 
2877   if (metrics_reporter_ != nullptr) {
2878     metrics_reporter_->NotifyAppInfoUpdated(&app_info_);
2879   }
2880 
2881   if (jit_.get() == nullptr) {
2882     // We are not JITing. Nothing to do.
2883     return;
2884   }
2885 
2886   VLOG(profiler) << "Register app with " << profile_output_filename
2887       << " " << android::base::Join(code_paths, ':');
2888   VLOG(profiler) << "Reference profile is: " << ref_profile_filename;
2889 
2890   if (profile_output_filename.empty()) {
2891     LOG(WARNING) << "JIT profile information will not be recorded: profile filename is empty.";
2892     return;
2893   }
2894   if (code_paths.empty()) {
2895     LOG(WARNING) << "JIT profile information will not be recorded: code paths is empty.";
2896     return;
2897   }
2898 
2899   // Framework calls this method for all split APKs. Ignore the calls for the ones with no dex code
2900   // so that we don't unnecessarily create profiles for them or write bootclasspath profiling info
2901   // to those profiles.
2902   bool has_code = false;
2903   for (const std::string& path : code_paths) {
2904     std::string error_msg;
2905     std::optional<uint32_t> checksum;
2906     std::vector<std::string> dex_locations;
2907     DexFileLoader loader(path);
2908     if (!loader.GetMultiDexChecksum(&checksum, &error_msg)) {
2909       LOG(WARNING) << error_msg;
2910       continue;
2911     }
2912     if (checksum.has_value()) {
2913       has_code = true;
2914       break;
2915     }
2916   }
2917   if (!has_code) {
2918     VLOG(profiler) << ART_FORMAT(
2919         "JIT profile information will not be recorded: no dex code in '{}'.",
2920         android::base::Join(code_paths, ','));
2921     return;
2922   }
2923 
2924   jit_->StartProfileSaver(profile_output_filename, code_paths, ref_profile_filename);
2925 }
2926 
SetFaultMessage(const std::string & message)2927 void Runtime::SetFaultMessage(const std::string& message) {
2928   std::string* new_msg = new std::string(message);
2929   std::string* cur_msg = fault_message_.exchange(new_msg);
2930   delete cur_msg;
2931 }
2932 
GetFaultMessage()2933 std::string Runtime::GetFaultMessage() {
2934   // Retrieve the message. Temporarily replace with null so that SetFaultMessage will not delete
2935   // the string in parallel.
2936   std::string* cur_msg = fault_message_.exchange(nullptr);
2937 
2938   // Make a copy of the string.
2939   std::string ret = cur_msg == nullptr ? "" : *cur_msg;
2940 
2941   // Put the message back if it hasn't been updated.
2942   std::string* null_str = nullptr;
2943   if (!fault_message_.compare_exchange_strong(null_str, cur_msg)) {
2944     // Already replaced.
2945     delete cur_msg;
2946   }
2947 
2948   return ret;
2949 }
2950 
AddCurrentRuntimeFeaturesAsDex2OatArguments(std::vector<std::string> * argv) const2951 void Runtime::AddCurrentRuntimeFeaturesAsDex2OatArguments(std::vector<std::string>* argv)
2952     const {
2953   if (GetInstrumentation()->InterpretOnly()) {
2954     argv->push_back("--compiler-filter=verify");
2955   }
2956 
2957   // Make the dex2oat instruction set match that of the launching runtime. If we have multiple
2958   // architecture support, dex2oat may be compiled as a different instruction-set than that
2959   // currently being executed.
2960   std::string instruction_set("--instruction-set=");
2961   instruction_set += GetInstructionSetString(kRuntimeISA);
2962   argv->push_back(instruction_set);
2963 
2964   if (InstructionSetFeatures::IsRuntimeDetectionSupported()) {
2965     argv->push_back("--instruction-set-features=runtime");
2966   } else {
2967     std::unique_ptr<const InstructionSetFeatures> features(
2968         InstructionSetFeatures::FromCppDefines());
2969     std::string feature_string("--instruction-set-features=");
2970     feature_string += features->GetFeatureString();
2971     argv->push_back(feature_string);
2972   }
2973 }
2974 
CreateJit()2975 void Runtime::CreateJit() {
2976   DCHECK(jit_code_cache_ == nullptr);
2977   DCHECK(jit_ == nullptr);
2978   if (kIsDebugBuild && GetInstrumentation()->IsForcedInterpretOnly()) {
2979     DCHECK(!jit_options_->UseJitCompilation());
2980   }
2981 
2982   if (!jit_options_->UseJitCompilation() && !jit_options_->GetSaveProfilingInfo()) {
2983     return;
2984   }
2985 
2986   if (IsSafeMode()) {
2987     LOG(INFO) << "Not creating JIT because of SafeMode.";
2988     return;
2989   }
2990 
2991   std::string error_msg;
2992   bool profiling_only = !jit_options_->UseJitCompilation();
2993   jit_code_cache_.reset(jit::JitCodeCache::Create(profiling_only,
2994                                                   /*rwx_memory_allowed=*/ true,
2995                                                   IsZygote(),
2996                                                   &error_msg));
2997   if (jit_code_cache_.get() == nullptr) {
2998     LOG(WARNING) << "Failed to create JIT Code Cache: " << error_msg;
2999     return;
3000   }
3001 
3002   jit_ = jit::Jit::Create(jit_code_cache_.get(), jit_options_.get());
3003   jit_->CreateThreadPool();
3004 }
3005 
CanRelocate() const3006 bool Runtime::CanRelocate() const {
3007   return !IsAotCompiler();
3008 }
3009 
IsCompilingBootImage() const3010 bool Runtime::IsCompilingBootImage() const {
3011   return IsCompiler() && compiler_callbacks_->IsBootImage();
3012 }
3013 
SetResolutionMethod(ArtMethod * method)3014 void Runtime::SetResolutionMethod(ArtMethod* method) {
3015   CHECK(method != nullptr);
3016   CHECK(method->IsRuntimeMethod()) << method;
3017   resolution_method_ = method;
3018 }
3019 
SetImtUnimplementedMethod(ArtMethod * method)3020 void Runtime::SetImtUnimplementedMethod(ArtMethod* method) {
3021   CHECK(method != nullptr);
3022   CHECK(method->IsRuntimeMethod());
3023   imt_unimplemented_method_ = method;
3024 }
3025 
FixupConflictTables()3026 void Runtime::FixupConflictTables() {
3027   // We can only do this after the class linker is created.
3028   const PointerSize pointer_size = GetClassLinker()->GetImagePointerSize();
3029   if (imt_unimplemented_method_->GetImtConflictTable(pointer_size) == nullptr) {
3030     imt_unimplemented_method_->SetImtConflictTable(
3031         ClassLinker::CreateImtConflictTable(/*count=*/0u, GetLinearAlloc(), pointer_size),
3032         pointer_size);
3033   }
3034   if (imt_conflict_method_->GetImtConflictTable(pointer_size) == nullptr) {
3035     imt_conflict_method_->SetImtConflictTable(
3036           ClassLinker::CreateImtConflictTable(/*count=*/0u, GetLinearAlloc(), pointer_size),
3037           pointer_size);
3038   }
3039 }
3040 
DisableVerifier()3041 void Runtime::DisableVerifier() {
3042   verify_ = verifier::VerifyMode::kNone;
3043 }
3044 
IsVerificationEnabled() const3045 bool Runtime::IsVerificationEnabled() const {
3046   return verify_ == verifier::VerifyMode::kEnable ||
3047       verify_ == verifier::VerifyMode::kSoftFail;
3048 }
3049 
IsVerificationSoftFail() const3050 bool Runtime::IsVerificationSoftFail() const {
3051   return verify_ == verifier::VerifyMode::kSoftFail;
3052 }
3053 
IsAsyncDeoptimizeable(ArtMethod * method,uintptr_t code) const3054 bool Runtime::IsAsyncDeoptimizeable(ArtMethod* method, uintptr_t code) const {
3055   if (OatQuickMethodHeader::NterpMethodHeader != nullptr) {
3056     if (OatQuickMethodHeader::NterpMethodHeader->Contains(code)) {
3057       return true;
3058     }
3059   }
3060 
3061   // We only support async deopt (ie the compiled code is not explicitly asking for
3062   // deopt, but something else like the debugger) in debuggable JIT code.
3063   // We could look at the oat file where `code` is being defined,
3064   // and check whether it's been compiled debuggable, but we decided to
3065   // only rely on the JIT for debuggable apps.
3066   // The JIT-zygote is not debuggable so we need to be sure to exclude code from the non-private
3067   // region as well.
3068   if (GetJit() != nullptr &&
3069       GetJit()->GetCodeCache()->PrivateRegionContainsPc(reinterpret_cast<const void*>(code))) {
3070     // If the code is JITed code then check if it was compiled as debuggable.
3071     const OatQuickMethodHeader* header = method->GetOatQuickMethodHeader(code);
3072     return CodeInfo::IsDebuggable(header->GetOptimizedCodeInfoPtr());
3073   }
3074 
3075   return false;
3076 }
3077 
3078 
CreateLinearAlloc()3079 LinearAlloc* Runtime::CreateLinearAlloc() {
3080   ArenaPool* pool = linear_alloc_arena_pool_.get();
3081   return pool != nullptr
3082       ? new LinearAlloc(pool, gUseUserfaultfd)
3083       : new LinearAlloc(arena_pool_.get(), /*track_allocs=*/ false);
3084 }
3085 
3086 class Runtime::SetupLinearAllocForZygoteFork : public AllocatorVisitor {
3087  public:
SetupLinearAllocForZygoteFork(Thread * self)3088   explicit SetupLinearAllocForZygoteFork(Thread* self) : self_(self) {}
3089 
Visit(LinearAlloc * alloc)3090   bool Visit(LinearAlloc* alloc) override {
3091     alloc->SetupForPostZygoteFork(self_);
3092     return true;
3093   }
3094 
3095  private:
3096   Thread* self_;
3097 };
3098 
SetupLinearAllocForPostZygoteFork(Thread * self)3099 void Runtime::SetupLinearAllocForPostZygoteFork(Thread* self) {
3100   if (gUseUserfaultfd) {
3101     // Setup all the linear-allocs out there for post-zygote fork. This will
3102     // basically force the arena allocator to ask for a new arena for the next
3103     // allocation. All arenas allocated from now on will be in the userfaultfd
3104     // visited space.
3105     if (GetLinearAlloc() != nullptr) {
3106       GetLinearAlloc()->SetupForPostZygoteFork(self);
3107     }
3108     if (GetStartupLinearAlloc() != nullptr) {
3109       GetStartupLinearAlloc()->SetupForPostZygoteFork(self);
3110     }
3111     {
3112       Locks::mutator_lock_->AssertNotHeld(self);
3113       ReaderMutexLock mu2(self, *Locks::mutator_lock_);
3114       ReaderMutexLock mu3(self, *Locks::classlinker_classes_lock_);
3115       SetupLinearAllocForZygoteFork visitor(self);
3116       GetClassLinker()->VisitAllocators(&visitor);
3117     }
3118     static_cast<GcVisitedArenaPool*>(GetLinearAllocArenaPool())->SetupPostZygoteMode();
3119   }
3120 }
3121 
GetHashTableMinLoadFactor() const3122 double Runtime::GetHashTableMinLoadFactor() const {
3123   return is_low_memory_mode_ ? kLowMemoryMinLoadFactor : kNormalMinLoadFactor;
3124 }
3125 
GetHashTableMaxLoadFactor() const3126 double Runtime::GetHashTableMaxLoadFactor() const {
3127   return is_low_memory_mode_ ? kLowMemoryMaxLoadFactor : kNormalMaxLoadFactor;
3128 }
3129 
UpdateProcessState(ProcessState process_state)3130 void Runtime::UpdateProcessState(ProcessState process_state) {
3131   ProcessState old_process_state = process_state_;
3132   process_state_ = process_state;
3133   GetHeap()->UpdateProcessState(old_process_state, process_state);
3134 }
3135 
RegisterSensitiveThread() const3136 void Runtime::RegisterSensitiveThread() const {
3137   Thread::SetJitSensitiveThread();
3138 }
3139 
3140 // Returns true if JIT compilations are enabled. GetJit() will be not null in this case.
UseJitCompilation() const3141 bool Runtime::UseJitCompilation() const {
3142   return (jit_ != nullptr) && jit_->UseJitCompilation();
3143 }
3144 
TakeSnapshot()3145 void Runtime::EnvSnapshot::TakeSnapshot() {
3146   char** env = GetEnviron();
3147   for (size_t i = 0; env[i] != nullptr; ++i) {
3148     name_value_pairs_.emplace_back(new std::string(env[i]));
3149   }
3150   // The strings in name_value_pairs_ retain ownership of the c_str, but we assign pointers
3151   // for quick use by GetSnapshot.  This avoids allocation and copying cost at Exec.
3152   c_env_vector_.reset(new char*[name_value_pairs_.size() + 1]);
3153   for (size_t i = 0; env[i] != nullptr; ++i) {
3154     c_env_vector_[i] = const_cast<char*>(name_value_pairs_[i]->c_str());
3155   }
3156   c_env_vector_[name_value_pairs_.size()] = nullptr;
3157 }
3158 
GetSnapshot() const3159 char** Runtime::EnvSnapshot::GetSnapshot() const {
3160   return c_env_vector_.get();
3161 }
3162 
AddSystemWeakHolder(gc::AbstractSystemWeakHolder * holder)3163 void Runtime::AddSystemWeakHolder(gc::AbstractSystemWeakHolder* holder) {
3164   gc::ScopedGCCriticalSection gcs(Thread::Current(),
3165                                   gc::kGcCauseAddRemoveSystemWeakHolder,
3166                                   gc::kCollectorTypeAddRemoveSystemWeakHolder);
3167   // Note: The ScopedGCCriticalSection also ensures that the rest of the function is in
3168   //       a critical section.
3169   system_weak_holders_.push_back(holder);
3170 }
3171 
RemoveSystemWeakHolder(gc::AbstractSystemWeakHolder * holder)3172 void Runtime::RemoveSystemWeakHolder(gc::AbstractSystemWeakHolder* holder) {
3173   gc::ScopedGCCriticalSection gcs(Thread::Current(),
3174                                   gc::kGcCauseAddRemoveSystemWeakHolder,
3175                                   gc::kCollectorTypeAddRemoveSystemWeakHolder);
3176   auto it = std::find(system_weak_holders_.begin(), system_weak_holders_.end(), holder);
3177   if (it != system_weak_holders_.end()) {
3178     system_weak_holders_.erase(it);
3179   }
3180 }
3181 
GetRuntimeCallbacks()3182 RuntimeCallbacks* Runtime::GetRuntimeCallbacks() {
3183   return callbacks_.get();
3184 }
3185 
3186 // Used to update boot image to not use AOT code. This is used when transitioning the runtime to
3187 // java debuggable. This visitor re-initializes the entry points without using AOT code. This also
3188 // disables shared hotness counters so the necessary methods can be JITed more efficiently.
3189 class DeoptimizeBootImageClassVisitor : public ClassVisitor {
3190  public:
DeoptimizeBootImageClassVisitor(instrumentation::Instrumentation * instrumentation)3191   explicit DeoptimizeBootImageClassVisitor(instrumentation::Instrumentation* instrumentation)
3192       : instrumentation_(instrumentation) {}
3193 
operator ()(ObjPtr<mirror::Class> klass)3194   bool operator()(ObjPtr<mirror::Class> klass) override REQUIRES(Locks::mutator_lock_) {
3195     DCHECK(Locks::mutator_lock_->IsExclusiveHeld(Thread::Current()));
3196     auto pointer_size = Runtime::Current()->GetClassLinker()->GetImagePointerSize();
3197     for (auto& m : klass->GetMethods(pointer_size)) {
3198       const void* code = m.GetEntryPointFromQuickCompiledCode();
3199       if (!m.IsInvokable()) {
3200         continue;
3201       }
3202       // For java debuggable runtimes we also deoptimize native methods. For other cases (boot
3203       // image profiling) we don't need to deoptimize native methods. If this changes also
3204       // update Instrumentation::CanUseAotCode.
3205       bool deoptimize_native_methods = Runtime::Current()->IsJavaDebuggable();
3206       if (Runtime::Current()->GetHeap()->IsInBootImageOatFile(code) &&
3207           (!m.IsNative() || deoptimize_native_methods) &&
3208           !m.IsProxyMethod()) {
3209         instrumentation_->InitializeMethodsCode(&m, /*aot_code=*/ nullptr);
3210       }
3211 
3212       if (Runtime::Current()->GetJit() != nullptr &&
3213           Runtime::Current()->GetJit()->GetCodeCache()->IsInZygoteExecSpace(code) &&
3214           (!m.IsNative() || deoptimize_native_methods)) {
3215         DCHECK(!m.IsProxyMethod());
3216         instrumentation_->InitializeMethodsCode(&m, /*aot_code=*/ nullptr);
3217       }
3218 
3219       if (m.IsPreCompiled()) {
3220         // Precompilation is incompatible with debuggable, so clear the flag
3221         // and update the entrypoint in case it has been compiled.
3222         m.ClearPreCompiled();
3223         instrumentation_->InitializeMethodsCode(&m, /*aot_code=*/ nullptr);
3224       }
3225 
3226       // Clear MemorySharedAccessFlags so the boot class methods can be JITed better.
3227       m.ClearMemorySharedMethod();
3228     }
3229     return true;
3230   }
3231 
3232  private:
3233   instrumentation::Instrumentation* const instrumentation_;
3234 };
3235 
SetRuntimeDebugState(RuntimeDebugState state)3236 void Runtime::SetRuntimeDebugState(RuntimeDebugState state) {
3237   if (state != RuntimeDebugState::kJavaDebuggableAtInit) {
3238     // We never change the state if we started as a debuggable runtime.
3239     DCHECK(runtime_debug_state_ != RuntimeDebugState::kJavaDebuggableAtInit);
3240   }
3241   runtime_debug_state_ = state;
3242 }
3243 
DeoptimizeBootImage()3244 void Runtime::DeoptimizeBootImage() {
3245   // If we've already started and we are setting this runtime to debuggable,
3246   // we patch entry points of methods in boot image to interpreter bridge, as
3247   // boot image code may be AOT compiled as not debuggable.
3248   DeoptimizeBootImageClassVisitor visitor(GetInstrumentation());
3249   GetClassLinker()->VisitClasses(&visitor);
3250   jit::Jit* jit = GetJit();
3251   if (jit != nullptr) {
3252     // Code previously compiled may not be compiled debuggable.
3253     jit->GetCodeCache()->TransitionToDebuggable();
3254   }
3255 }
3256 
ScopedThreadPoolUsage()3257 Runtime::ScopedThreadPoolUsage::ScopedThreadPoolUsage()
3258     : thread_pool_(Runtime::Current()->AcquireThreadPool()) {}
3259 
~ScopedThreadPoolUsage()3260 Runtime::ScopedThreadPoolUsage::~ScopedThreadPoolUsage() {
3261   Runtime::Current()->ReleaseThreadPool();
3262 }
3263 
DeleteThreadPool()3264 bool Runtime::DeleteThreadPool() {
3265   // Make sure workers are started to prevent thread shutdown errors.
3266   WaitForThreadPoolWorkersToStart();
3267   std::unique_ptr<ThreadPool> thread_pool;
3268   {
3269     MutexLock mu(Thread::Current(), *Locks::runtime_thread_pool_lock_);
3270     if (thread_pool_ref_count_ == 0) {
3271       thread_pool = std::move(thread_pool_);
3272     }
3273   }
3274   return thread_pool != nullptr;
3275 }
3276 
AcquireThreadPool()3277 ThreadPool* Runtime::AcquireThreadPool() {
3278   MutexLock mu(Thread::Current(), *Locks::runtime_thread_pool_lock_);
3279   ++thread_pool_ref_count_;
3280   return thread_pool_.get();
3281 }
3282 
ReleaseThreadPool()3283 void Runtime::ReleaseThreadPool() {
3284   MutexLock mu(Thread::Current(), *Locks::runtime_thread_pool_lock_);
3285   CHECK_GT(thread_pool_ref_count_, 0u);
3286   --thread_pool_ref_count_;
3287 }
3288 
WaitForThreadPoolWorkersToStart()3289 void Runtime::WaitForThreadPoolWorkersToStart() {
3290   // Need to make sure workers are created before deleting the pool.
3291   ScopedThreadPoolUsage stpu;
3292   if (stpu.GetThreadPool() != nullptr) {
3293     stpu.GetThreadPool()->WaitForWorkersToBeCreated();
3294   }
3295 }
3296 
ResetStartupCompleted()3297 void Runtime::ResetStartupCompleted() {
3298   startup_completed_.store(false, std::memory_order_seq_cst);
3299 }
3300 
NotifyStartupCompleted()3301 bool Runtime::NotifyStartupCompleted() {
3302   DCHECK(!IsZygote());
3303   bool expected = false;
3304   if (!startup_completed_.compare_exchange_strong(expected, true, std::memory_order_seq_cst)) {
3305     // Right now NotifyStartupCompleted will be called up to twice, once from profiler and up to
3306     // once externally. For this reason there are no asserts.
3307     return false;
3308   }
3309 
3310   VLOG(startup) << app_info_;
3311 
3312   ProfileSaver::NotifyStartupCompleted();
3313 
3314   if (metrics_reporter_ != nullptr) {
3315     metrics_reporter_->NotifyStartupCompleted();
3316   }
3317   return true;
3318 }
3319 
NotifyDexFileLoaded()3320 void Runtime::NotifyDexFileLoaded() {
3321   if (metrics_reporter_ != nullptr) {
3322     metrics_reporter_->NotifyAppInfoUpdated(&app_info_);
3323   }
3324 }
3325 
GetStartupCompleted() const3326 bool Runtime::GetStartupCompleted() const {
3327   return startup_completed_.load(std::memory_order_seq_cst);
3328 }
3329 
SetSignalHookDebuggable(bool value)3330 void Runtime::SetSignalHookDebuggable(bool value) {
3331   SkipAddSignalHandler(value);
3332 }
3333 
SetJniIdType(JniIdType t)3334 void Runtime::SetJniIdType(JniIdType t) {
3335   CHECK(CanSetJniIdType()) << "Not allowed to change id type!";
3336   if (t == GetJniIdType()) {
3337     return;
3338   }
3339   jni_ids_indirection_ = t;
3340   JNIEnvExt::ResetFunctionTable();
3341   WellKnownClasses::HandleJniIdTypeChange(Thread::Current()->GetJniEnv());
3342 }
3343 
IsSystemServerProfiled() const3344 bool Runtime::IsSystemServerProfiled() const {
3345   return IsSystemServer() && jit_options_->GetSaveProfilingInfo();
3346 }
3347 
GetOatFilesExecutable() const3348 bool Runtime::GetOatFilesExecutable() const {
3349   return !IsAotCompiler() && !IsSystemServerProfiled();
3350 }
3351 
MadviseFileForRange(size_t madvise_size_limit_bytes,size_t map_size_bytes,const uint8_t * map_begin,const uint8_t * map_end,const std::string & file_name)3352 void Runtime::MadviseFileForRange(size_t madvise_size_limit_bytes,
3353                                   size_t map_size_bytes,
3354                                   const uint8_t* map_begin,
3355                                   const uint8_t* map_end,
3356                                   const std::string& file_name) {
3357   map_begin = AlignDown(map_begin, gPageSize);
3358   map_size_bytes = RoundUp(map_size_bytes, gPageSize);
3359 #ifdef ART_TARGET_ANDROID
3360   // Short-circuit the madvise optimization for background processes. This
3361   // avoids IO and memory contention with foreground processes, particularly
3362   // those involving app startup.
3363   // Note: We can only safely short-circuit the madvise on T+, as it requires
3364   // the framework to always immediately notify ART of process states.
3365   static const int kApiLevel = android_get_device_api_level();
3366   const bool accurate_process_state_at_startup = kApiLevel >= __ANDROID_API_T__;
3367   if (accurate_process_state_at_startup) {
3368     const Runtime* runtime = Runtime::Current();
3369     if (runtime != nullptr && !runtime->InJankPerceptibleProcessState()) {
3370       return;
3371     }
3372   }
3373 #endif  // ART_TARGET_ANDROID
3374 
3375   // Ideal blockTransferSize for madvising files (128KiB)
3376   static constexpr size_t kIdealIoTransferSizeBytes = 128*1024;
3377 
3378   size_t target_size_bytes = std::min<size_t>(map_size_bytes, madvise_size_limit_bytes);
3379 
3380   if (target_size_bytes > 0) {
3381     ScopedTrace madvising_trace("madvising "
3382                                 + file_name
3383                                 + " size="
3384                                 + std::to_string(target_size_bytes));
3385 
3386     // Based on requested size (target_size_bytes)
3387     const uint8_t* target_pos = map_begin + target_size_bytes;
3388 
3389     // Clamp endOfFile if its past map_end
3390     if (target_pos > map_end) {
3391       target_pos = map_end;
3392     }
3393 
3394     // Madvise the whole file up to target_pos in chunks of
3395     // kIdealIoTransferSizeBytes (to MADV_WILLNEED)
3396     // Note:
3397     // madvise(MADV_WILLNEED) will prefetch max(fd readahead size, optimal
3398     // block size for device) per call, hence the need for chunks. (128KB is a
3399     // good default.)
3400     for (const uint8_t* madvise_start = map_begin;
3401          madvise_start < target_pos;
3402          madvise_start += kIdealIoTransferSizeBytes) {
3403       void* madvise_addr = const_cast<void*>(reinterpret_cast<const void*>(madvise_start));
3404       size_t madvise_length = std::min(kIdealIoTransferSizeBytes,
3405                                        static_cast<size_t>(target_pos - madvise_start));
3406       int status = madvise(madvise_addr, madvise_length, MADV_WILLNEED);
3407       // In case of error we stop madvising rest of the file
3408       if (status < 0) {
3409         LOG(ERROR) << "Failed to madvise file " << file_name
3410                    << " for size:" << map_size_bytes
3411                    << ": " << strerror(errno);
3412         break;
3413       }
3414     }
3415   }
3416 }
3417 
3418 // Return whether a boot image has a profile. This means we'll need to pre-JIT
3419 // methods in that profile for performance.
HasImageWithProfile() const3420 bool Runtime::HasImageWithProfile() const {
3421   for (gc::space::ImageSpace* space : GetHeap()->GetBootImageSpaces()) {
3422     if (!space->GetProfileFiles().empty()) {
3423       return true;
3424     }
3425   }
3426   return false;
3427 }
3428 
AppendToBootClassPath(const std::string & filename,const std::string & location)3429 void Runtime::AppendToBootClassPath(const std::string& filename, const std::string& location) {
3430   DCHECK(!DexFileLoader::IsMultiDexLocation(filename));
3431   boot_class_path_.push_back(filename);
3432   if (!boot_class_path_locations_.empty()) {
3433     DCHECK(!DexFileLoader::IsMultiDexLocation(location));
3434     boot_class_path_locations_.push_back(location);
3435   }
3436 }
3437 
AppendToBootClassPath(const std::string & filename,const std::string & location,const std::vector<std::unique_ptr<const art::DexFile>> & dex_files)3438 void Runtime::AppendToBootClassPath(
3439     const std::string& filename,
3440     const std::string& location,
3441     const std::vector<std::unique_ptr<const art::DexFile>>& dex_files) {
3442   AppendToBootClassPath(filename, location);
3443   ScopedObjectAccess soa(Thread::Current());
3444   for (const std::unique_ptr<const art::DexFile>& dex_file : dex_files) {
3445     // The first element must not be at a multi-dex location, while other elements must be.
3446     DCHECK_NE(DexFileLoader::IsMultiDexLocation(dex_file->GetLocation()),
3447               dex_file.get() == dex_files.begin()->get());
3448     GetClassLinker()->AppendToBootClassPath(Thread::Current(), dex_file.get());
3449   }
3450 }
3451 
AppendToBootClassPath(const std::string & filename,const std::string & location,const std::vector<const art::DexFile * > & dex_files)3452 void Runtime::AppendToBootClassPath(const std::string& filename,
3453                                     const std::string& location,
3454                                     const std::vector<const art::DexFile*>& dex_files) {
3455   AppendToBootClassPath(filename, location);
3456   ScopedObjectAccess soa(Thread::Current());
3457   for (const art::DexFile* dex_file : dex_files) {
3458     // The first element must not be at a multi-dex location, while other elements must be.
3459     DCHECK_NE(DexFileLoader::IsMultiDexLocation(dex_file->GetLocation()),
3460               dex_file == *dex_files.begin());
3461     GetClassLinker()->AppendToBootClassPath(Thread::Current(), dex_file);
3462   }
3463 }
3464 
AppendToBootClassPath(const std::string & filename,const std::string & location,const std::vector<std::pair<const art::DexFile *,ObjPtr<mirror::DexCache>>> & dex_files_and_cache)3465 void Runtime::AppendToBootClassPath(
3466     const std::string& filename,
3467     const std::string& location,
3468     const std::vector<std::pair<const art::DexFile*, ObjPtr<mirror::DexCache>>>&
3469         dex_files_and_cache) {
3470   AppendToBootClassPath(filename, location);
3471   ScopedObjectAccess soa(Thread::Current());
3472   for (const auto& [dex_file, dex_cache] : dex_files_and_cache) {
3473     // The first element must not be at a multi-dex location, while other elements must be.
3474     DCHECK_NE(DexFileLoader::IsMultiDexLocation(dex_file->GetLocation()),
3475               dex_file == dex_files_and_cache.begin()->first);
3476     GetClassLinker()->AppendToBootClassPath(dex_file, dex_cache);
3477   }
3478 }
3479 
AddExtraBootDexFiles(const std::string & filename,const std::string & location,std::vector<std::unique_ptr<const art::DexFile>> && dex_files)3480 void Runtime::AddExtraBootDexFiles(const std::string& filename,
3481                                    const std::string& location,
3482                                    std::vector<std::unique_ptr<const art::DexFile>>&& dex_files) {
3483   AppendToBootClassPath(filename, location);
3484   ScopedObjectAccess soa(Thread::Current());
3485   if (kIsDebugBuild) {
3486     for (const std::unique_ptr<const art::DexFile>& dex_file : dex_files) {
3487       // The first element must not be at a multi-dex location, while other elements must be.
3488       DCHECK_NE(DexFileLoader::IsMultiDexLocation(dex_file->GetLocation()),
3489                 dex_file.get() == dex_files.begin()->get());
3490     }
3491   }
3492   GetClassLinker()->AddExtraBootDexFiles(Thread::Current(), std::move(dex_files));
3493 }
3494 
3495 }  // namespace art
3496