Vladimir Marko | f52d92f | 2019-03-29 12:33:02 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2014 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 "monitor_objects_stack_visitor.h" |
| 18 | |
| 19 | #include "obj_ptr-inl.h" |
| 20 | #include "read_barrier-inl.h" |
| 21 | #include "thread-current-inl.h" |
| 22 | |
| 23 | namespace art { |
| 24 | |
| 25 | bool MonitorObjectsStackVisitor::VisitFrame() { |
| 26 | ArtMethod* m = GetMethod(); |
| 27 | if (m->IsRuntimeMethod()) { |
| 28 | return true; |
| 29 | } |
| 30 | |
| 31 | VisitMethodResult vmrEntry = StartMethod(m, frame_count); |
| 32 | switch (vmrEntry) { |
| 33 | case VisitMethodResult::kContinueMethod: |
| 34 | break; |
| 35 | case VisitMethodResult::kSkipMethod: |
| 36 | return true; |
| 37 | case VisitMethodResult::kEndStackWalk: |
| 38 | return false; |
| 39 | } |
| 40 | |
| 41 | if (frame_count == 0) { |
| 42 | // Top frame, check for blocked state. |
| 43 | |
| 44 | ObjPtr<mirror::Object> monitor_object; |
| 45 | uint32_t lock_owner_tid; |
| 46 | ThreadState state = Monitor::FetchState(GetThread(), |
| 47 | &monitor_object, |
| 48 | &lock_owner_tid); |
| 49 | switch (state) { |
| 50 | case kWaiting: |
| 51 | case kTimedWaiting: |
| 52 | VisitWaitingObject(monitor_object, state); |
| 53 | break; |
| 54 | case kSleeping: |
| 55 | VisitSleepingObject(monitor_object); |
| 56 | break; |
| 57 | |
| 58 | case kBlocked: |
| 59 | case kWaitingForLockInflation: |
| 60 | VisitBlockedOnObject(monitor_object, state, lock_owner_tid); |
| 61 | break; |
| 62 | |
| 63 | default: |
| 64 | break; |
| 65 | } |
| 66 | } |
| 67 | |
| 68 | if (dump_locks) { |
| 69 | // Visit locks, but do not abort on errors. This could trigger a nested abort. |
| 70 | // Skip visiting locks if dump_locks is false as it would cause a bad_mutexes_held in |
| 71 | // RegTypeCache::RegTypeCache due to thread_list_lock. |
| 72 | Monitor::VisitLocks(this, VisitLockedObject, this, false); |
| 73 | } |
| 74 | |
| 75 | ++frame_count; |
| 76 | |
| 77 | VisitMethodResult vmrExit = EndMethod(m); |
| 78 | switch (vmrExit) { |
| 79 | case VisitMethodResult::kContinueMethod: |
| 80 | case VisitMethodResult::kSkipMethod: |
| 81 | return true; |
| 82 | |
| 83 | case VisitMethodResult::kEndStackWalk: |
| 84 | return false; |
| 85 | } |
| 86 | LOG(FATAL) << "Unreachable"; |
| 87 | UNREACHABLE(); |
| 88 | } |
| 89 | |
| 90 | void MonitorObjectsStackVisitor::VisitLockedObject(ObjPtr<mirror::Object> o, void* context) { |
| 91 | MonitorObjectsStackVisitor* self = reinterpret_cast<MonitorObjectsStackVisitor*>(context); |
| 92 | if (o != nullptr) { |
| 93 | if (kUseReadBarrier && Thread::Current()->GetIsGcMarking()) { |
| 94 | // We may call Thread::Dump() in the middle of the CC thread flip and this thread's stack |
| 95 | // may have not been flipped yet and "o" may be a from-space (stale) ref, in which case the |
| 96 | // IdentityHashCode call below will crash. So explicitly mark/forward it here. |
| 97 | o = ReadBarrier::Mark(o.Ptr()); |
| 98 | } |
| 99 | } |
| 100 | self->VisitLockedObject(o); |
| 101 | } |
| 102 | |
| 103 | } // namespace art |