monitor.cc revision b9001abff3a45f1ae90536da7dd1ec28a6ae0174
15f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 25f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Copyright (C) 2008 The Android Open Source Project 35f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 45f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Licensed under the Apache License, Version 2.0 (the "License"); 55f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * you may not use this file except in compliance with the License. 65f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * You may obtain a copy of the License at 75f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 85f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * http://www.apache.org/licenses/LICENSE-2.0 95f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 105f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Unless required by applicable law or agreed to in writing, software 115f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * distributed under the License is distributed on an "AS IS" BASIS, 125f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 135f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * See the License for the specific language governing permissions and 145f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * limitations under the License. 155f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 165f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1754e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes#include "monitor.h" 185f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1908fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes#include <vector> 2008fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 2176b6167407c2b6f5d40ad895b2793a6b037f54b2Elliott Hughes#include "base/mutex.h" 221aa246dec5abe212f699de1413a0c4a191ca364aElliott Hughes#include "base/stl_util.h" 2333dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao#include "class_linker.h" 244f6ad8ab428038129b2d0d6c40b7fd625cca15e1Ian Rogers#include "dex_file-inl.h" 2508fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes#include "dex_instruction.h" 26d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers#include "lock_word-inl.h" 27ea46f950e7a51585db293cd7f047de190a482414Brian Carlstrom#include "mirror/art_method-inl.h" 284f6ad8ab428038129b2d0d6c40b7fd625cca15e1Ian Rogers#include "mirror/class-inl.h" 2905f3057d6a4d23d712092ccd36a531590bff323bIan Rogers#include "mirror/object-inl.h" 302dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogers#include "mirror/object_array-inl.h" 3100f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers#include "scoped_thread_state_change.h" 325f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#include "thread.h" 338e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes#include "thread_list.h" 3408fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes#include "verifier/method_verifier.h" 35044288fb8f69e154862763a6b3bfea2bac1b397eElliott Hughes#include "well_known_classes.h" 365f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesnamespace art { 385f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 39b9001abff3a45f1ae90536da7dd1ec28a6ae0174Mathieu Chartierstatic constexpr uint64_t kLongWaitMs = 100; 40b9001abff3a45f1ae90536da7dd1ec28a6ae0174Mathieu Chartier 415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 42d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * Every Object has a monitor associated with it, but not every Object is actually locked. Even 43d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * the ones that are locked do not need a full-fledged monitor until a) there is actual contention 44d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * or b) wait() is called on the Object. 455f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 46d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * For Android, we have implemented a scheme similar to the one described in Bacon et al.'s 47d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * "Thin locks: featherweight synchronization for Java" (ACM 1998). Things are even easier for us, 48d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * though, because we have a full 32 bits to work with. 495f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 50d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * The two states of an Object's lock are referred to as "thin" and "fat". A lock may transition 51d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * from the "thin" state to the "fat" state and this transition is referred to as inflation. Once 52d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * a lock has been inflated it remains in the "fat" state indefinitely. 535f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 54d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * The lock value itself is stored in mirror::Object::monitor_ and the representation is described 55d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * in the LockWord value type. 5654e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes * 575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Monitors provide: 585f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - mutually exclusive access to resources 595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - a way for multiple threads to wait for notification 605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 615f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * In effect, they fill the role of both mutexes and condition variables. 625f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 63d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * Only one thread can own the monitor at any time. There may be several threads waiting on it 64d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * (the wait call unlocks it). One or more waiting threads may be getting interrupted or notified 65d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * at any given time. 665f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 6754e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes 68fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughesbool (*Monitor::is_sensitive_thread_hook_)() = NULL; 69fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughesuint32_t Monitor::lock_profiling_threshold_ = 0; 7032d6e1e5654433d7eadede89e1c770b2c839aee9Elliott Hughes 71fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughesbool Monitor::IsSensitiveThread() { 72fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes if (is_sensitive_thread_hook_ != NULL) { 73fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes return (*is_sensitive_thread_hook_)(); 74fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 75fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes return false; 76fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes} 77fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes 784dd9b4d95eec9db5338fb9bf132f9bb8facf6cf4Elliott Hughesvoid Monitor::Init(uint32_t lock_profiling_threshold, bool (*is_sensitive_thread_hook)()) { 79fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes lock_profiling_threshold_ = lock_profiling_threshold; 80fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes is_sensitive_thread_hook_ = is_sensitive_thread_hook; 8132d6e1e5654433d7eadede89e1c770b2c839aee9Elliott Hughes} 8232d6e1e5654433d7eadede89e1c770b2c839aee9Elliott Hughes 83ef7d42fca18c16fbaf103822ad16f23246e2905dIan RogersMonitor::Monitor(Thread* self, Thread* owner, mirror::Object* obj, int32_t hash_code) 8400f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers : monitor_lock_("a monitor lock", kMonitorLock), 85d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_contenders_("monitor contenders", monitor_lock_), 8646bc778f1feed02b20d25e3d03470c93ca2c0506Mathieu Chartier num_waiters_(0), 8700f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers owner_(owner), 885f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes lock_count_(0), 8994f7b49578b6aaa80de8ffed230648d601393905Hiroshi Yamauchi obj_(GcRoot<mirror::Object>(obj)), 905f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wait_set_(NULL), 91ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier hash_code_(hash_code), 9233dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_method_(NULL), 93ef7d42fca18c16fbaf103822ad16f23246e2905dIan Rogers locking_dex_pc_(0), 9474240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe monitor_id_(MonitorPool::ComputeMonitorId(this, self)) { 9574240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe#ifdef __LP64__ 9674240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe DCHECK(false) << "Should not be reached in 64b"; 9774240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe next_free_ = nullptr; 9874240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe#endif 9974240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe // We should only inflate a lock if the owner is ourselves or suspended. This avoids a race 10074240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe // with the owner unlocking the thin-lock. 10174240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe CHECK(owner == nullptr || owner == self || owner->IsSuspended()); 10274240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe // The identity hash code is set for the life time of the monitor. 10374240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe} 10474240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe 10574240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas GampeMonitor::Monitor(Thread* self, Thread* owner, mirror::Object* obj, int32_t hash_code, 10674240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe MonitorId id) 10774240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe : monitor_lock_("a monitor lock", kMonitorLock), 10874240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe monitor_contenders_("monitor contenders", monitor_lock_), 10974240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe num_waiters_(0), 11074240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe owner_(owner), 11174240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe lock_count_(0), 11294f7b49578b6aaa80de8ffed230648d601393905Hiroshi Yamauchi obj_(GcRoot<mirror::Object>(obj)), 11374240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe wait_set_(NULL), 11474240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe hash_code_(hash_code), 11574240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe locking_method_(NULL), 11674240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe locking_dex_pc_(0), 11774240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe monitor_id_(id) { 11874240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe#ifdef __LP64__ 11974240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe next_free_ = nullptr; 12074240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe#endif 121d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // We should only inflate a lock if the owner is ourselves or suspended. This avoids a race 122d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // with the owner unlocking the thin-lock. 123ef7d42fca18c16fbaf103822ad16f23246e2905dIan Rogers CHECK(owner == nullptr || owner == self || owner->IsSuspended()); 124ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // The identity hash code is set for the life time of the monitor. 125d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers} 126d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers 1274e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartierint32_t Monitor::GetHashCode() { 1284e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartier while (!HasHashCode()) { 1293e5cf305db800b2989ad57b7cde8fb3cc9fa1b9eIan Rogers if (hash_code_.CompareExchangeWeakRelaxed(0, mirror::Object::GenerateIdentityHashCode())) { 1304e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartier break; 1314e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartier } 1324e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartier } 1334e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartier DCHECK(HasHashCode()); 1343e5cf305db800b2989ad57b7cde8fb3cc9fa1b9eIan Rogers return hash_code_.LoadRelaxed(); 1354e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartier} 1364e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartier 137d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogersbool Monitor::Install(Thread* self) { 138d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(self, monitor_lock_); // Uncontended mutex acquisition as monitor isn't yet public. 139ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier CHECK(owner_ == nullptr || owner_ == self || owner_->IsSuspended()); 14000f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Propagate the lock state. 1414cba0d979a11f955e6ec3c0f1bf61478af7aa810Hiroshi Yamauchi LockWord lw(GetObject()->GetLockWord(false)); 142ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier switch (lw.GetState()) { 143ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kThinLocked: { 144ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier CHECK_EQ(owner_->GetThreadId(), lw.ThinLockOwner()); 145ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier lock_count_ = lw.ThinLockCount(); 146ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier break; 147ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 148ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: { 1493e5cf305db800b2989ad57b7cde8fb3cc9fa1b9eIan Rogers CHECK_EQ(hash_code_.LoadRelaxed(), static_cast<int32_t>(lw.GetHashCode())); 150ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier break; 151ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 152ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kFatLocked: { 153ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // The owner_ is suspended but another thread beat us to install a monitor. 154ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier return false; 155ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 156ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kUnlocked: { 157ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier LOG(FATAL) << "Inflating unlocked lock word"; 158ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier break; 159ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 160590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier default: { 161590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier LOG(FATAL) << "Invalid monitor state " << lw.GetState(); 162590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier return false; 163590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 164d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 165d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LockWord fat(this); 166d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Publish the updated lock word, which may race with other threads. 167228602f562f1d130d06e60a98752d99c2d467d6aIan Rogers bool success = GetObject()->CasLockWordWeakSequentiallyConsistent(lw, fat); 16800f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Lock profiling. 1699728f91a63016136261231ff5213bde703bd27b6Mathieu Chartier if (success && owner_ != nullptr && lock_profiling_threshold_ != 0) { 1706ec8ebd178ed39aa09e4c7fad194900114c4121aAndreas Gampe // Do not abort on dex pc errors. This can easily happen when we want to dump a stack trace on 1716ec8ebd178ed39aa09e4c7fad194900114c4121aAndreas Gampe // abort. 1726ec8ebd178ed39aa09e4c7fad194900114c4121aAndreas Gampe locking_method_ = owner_->GetCurrentMethod(&locking_dex_pc_, false); 17300f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } 174d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return success; 1755f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 1765f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1775f79133a435ebcb20000370d56046fe01201dd80Elliott HughesMonitor::~Monitor() { 178590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // Deflated monitors have a null object. 1795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 1805f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1815f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 1825f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Links a thread into a monitor's wait set. The monitor lock must be 1835f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * held by the caller of this routine. 1845f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 1855f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::AppendToWaitSet(Thread* thread) { 1865f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(owner_ == Thread::Current()); 1875f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(thread != NULL); 188dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers DCHECK(thread->GetWaitNext() == nullptr) << thread->GetWaitNext(); 1895f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (wait_set_ == NULL) { 1905f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wait_set_ = thread; 1915f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 1925f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 1935f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1945f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // push_back. 1955f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* t = wait_set_; 196dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers while (t->GetWaitNext() != nullptr) { 197dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers t = t->GetWaitNext(); 1985f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 199dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers t->SetWaitNext(thread); 2005f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 2015f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 2025f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 2035f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Unlinks a thread from a monitor's wait set. The monitor lock must 2045f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * be held by the caller of this routine. 2055f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 2065f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::RemoveFromWaitSet(Thread *thread) { 2075f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(owner_ == Thread::Current()); 2085f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(thread != NULL); 2095f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (wait_set_ == NULL) { 2105f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 2115f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 2125f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (wait_set_ == thread) { 213dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers wait_set_ = thread->GetWaitNext(); 214dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers thread->SetWaitNext(nullptr); 2155f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 2165f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 2175f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 2185f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* t = wait_set_; 219dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers while (t->GetWaitNext() != NULL) { 220dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers if (t->GetWaitNext() == thread) { 221dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers t->SetWaitNext(thread->GetWaitNext()); 222dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers thread->SetWaitNext(nullptr); 2235f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 2245f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 225dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers t = t->GetWaitNext(); 2265f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 2275f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 2285f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 2296aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartiervoid Monitor::SetObject(mirror::Object* object) { 23094f7b49578b6aaa80de8ffed230648d601393905Hiroshi Yamauchi obj_ = GcRoot<mirror::Object>(object); 2316aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier} 2326aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier 2335f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::Lock(Thread* self) { 234d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(self, monitor_lock_); 235d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers while (true) { 236440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier if (owner_ == nullptr) { // Unowned. 237d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers owner_ = self; 238d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers CHECK_EQ(lock_count_, 0); 239d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // When debugging, save the current monitor holder for future 240d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // acquisition failures to use in sampled logging. 241d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (lock_profiling_threshold_ != 0) { 242d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers locking_method_ = self->GetCurrentMethod(&locking_dex_pc_); 243fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 244d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; 245d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else if (owner_ == self) { // Recursive. 246d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers lock_count_++; 247d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; 248fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 249d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Contended. 250d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers const bool log_contention = (lock_profiling_threshold_ != 0); 251b894a19dfd668b6779de939cf5265b7e409d8809Xin Guan uint64_t wait_start_ms = log_contention ? MilliTime() : 0; 252ef7d42fca18c16fbaf103822ad16f23246e2905dIan Rogers mirror::ArtMethod* owners_method = locking_method_; 253d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t owners_dex_pc = locking_dex_pc_; 254440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier // Do this before releasing the lock so that we don't get deflated. 255b9001abff3a45f1ae90536da7dd1ec28a6ae0174Mathieu Chartier size_t num_waiters = num_waiters_; 256440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier ++num_waiters_; 257d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Unlock(self); // Let go of locks in order. 258a6e7f0872c42009ecbee82d7fbe452deef9ae65bMathieu Chartier self->SetMonitorEnterObject(GetObject()); 259d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers { 260d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers ScopedThreadStateChange tsc(self, kBlocked); // Change to blocked and give up mutator_lock_. 261d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu2(self, monitor_lock_); // Reacquire monitor_lock_ without mutator_lock_ for Wait. 262d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (owner_ != NULL) { // Did the owner_ give the lock up? 263d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_contenders_.Wait(self); // Still contended so wait. 264d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Woken from contention. 265d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (log_contention) { 266d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint64_t wait_ms = MilliTime() - wait_start_ms; 267d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t sample_percent; 268d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (wait_ms >= lock_profiling_threshold_) { 269d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers sample_percent = 100; 270d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 271d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers sample_percent = 100 * wait_ms / lock_profiling_threshold_; 272d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 273d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (sample_percent != 0 && (static_cast<uint32_t>(rand() % 100) < sample_percent)) { 274d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers const char* owners_filename; 275d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t owners_line_number; 276d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers TranslateLocation(owners_method, owners_dex_pc, &owners_filename, &owners_line_number); 277b9001abff3a45f1ae90536da7dd1ec28a6ae0174Mathieu Chartier if (wait_ms > kLongWaitMs && owners_method != nullptr) { 278b9001abff3a45f1ae90536da7dd1ec28a6ae0174Mathieu Chartier LOG(WARNING) << "Long monitor contention event with owner method=" 279b9001abff3a45f1ae90536da7dd1ec28a6ae0174Mathieu Chartier << PrettyMethod(owners_method) << " from " << owners_filename << ":" 280b9001abff3a45f1ae90536da7dd1ec28a6ae0174Mathieu Chartier << owners_line_number << " waiters=" << num_waiters << " for " 281b9001abff3a45f1ae90536da7dd1ec28a6ae0174Mathieu Chartier << PrettyDuration(MsToNs(wait_ms)); 282b9001abff3a45f1ae90536da7dd1ec28a6ae0174Mathieu Chartier } 283d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LogContentionEvent(self, wait_ms, sample_percent, owners_filename, owners_line_number); 284d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 285d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 286fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 2875f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 288a6e7f0872c42009ecbee82d7fbe452deef9ae65bMathieu Chartier self->SetMonitorEnterObject(nullptr); 289d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Lock(self); // Reacquire locks in order. 290440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier --num_waiters_; 291fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 2925f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 2935f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 2946d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogersstatic void ThrowIllegalMonitorStateExceptionF(const char* fmt, ...) 2956d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers __attribute__((format(printf, 1, 2))); 2966d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers 29700f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogersstatic void ThrowIllegalMonitorStateExceptionF(const char* fmt, ...) 298b726dcb581bf72da46527378ccb6889020f0e6e9Ian Rogers SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 2996d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers va_list args; 3006d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers va_start(args, fmt); 30162d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers Thread* self = Thread::Current(); 30262d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers ThrowLocation throw_location = self->GetCurrentLocationForThrow(); 30362d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers self->ThrowNewExceptionV(throw_location, "Ljava/lang/IllegalMonitorStateException;", fmt, args); 304d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (!Runtime::Current()->IsStarted() || VLOG_IS_ON(monitor)) { 30564277f38032208a0c1081ff9e466c04009b96383Brian Carlstrom std::ostringstream ss; 30662d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers self->Dump(ss); 307d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LOG(Runtime::Current()->IsStarted() ? INFO : ERROR) 308d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers << self->GetException(NULL)->Dump() << "\n" << ss.str(); 30964277f38032208a0c1081ff9e466c04009b96383Brian Carlstrom } 3106d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers va_end(args); 3116d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers} 3126d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers 313d423741f91526cada9d081c64ee295ec9863032dElliott Hughesstatic std::string ThreadToString(Thread* thread) { 314d423741f91526cada9d081c64ee295ec9863032dElliott Hughes if (thread == NULL) { 315d423741f91526cada9d081c64ee295ec9863032dElliott Hughes return "NULL"; 316d423741f91526cada9d081c64ee295ec9863032dElliott Hughes } 317d423741f91526cada9d081c64ee295ec9863032dElliott Hughes std::ostringstream oss; 318d423741f91526cada9d081c64ee295ec9863032dElliott Hughes // TODO: alternatively, we could just return the thread's name. 319d423741f91526cada9d081c64ee295ec9863032dElliott Hughes oss << *thread; 320d423741f91526cada9d081c64ee295ec9863032dElliott Hughes return oss.str(); 321d423741f91526cada9d081c64ee295ec9863032dElliott Hughes} 322d423741f91526cada9d081c64ee295ec9863032dElliott Hughes 3232dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersvoid Monitor::FailedUnlock(mirror::Object* o, Thread* expected_owner, Thread* found_owner, 324ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes Monitor* monitor) { 325ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes Thread* current_owner = NULL; 326ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes std::string current_owner_string; 327ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes std::string expected_owner_string; 328ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes std::string found_owner_string; 329ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes { 330ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes // TODO: isn't this too late to prevent threads from disappearing? 331ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes // Acquire thread list lock so threads won't disappear from under us. 33250b35e2fd1a68cd1240e4a9d9f363e11764957d1Ian Rogers MutexLock mu(Thread::Current(), *Locks::thread_list_lock_); 333ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes // Re-read owner now that we hold lock. 334d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers current_owner = (monitor != NULL) ? monitor->GetOwner() : NULL; 335ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes // Get short descriptions of the threads involved. 336ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes current_owner_string = ThreadToString(current_owner); 337ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string = ThreadToString(expected_owner); 338ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes found_owner_string = ThreadToString(found_owner); 339ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes } 3406d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (current_owner == NULL) { 3416d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (found_owner == NULL) { 3426d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of unowned monitor on object of type '%s'" 3436d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " on thread '%s'", 344ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes PrettyTypeOf(o).c_str(), 345ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string.c_str()); 3466d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 3476d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers // Race: the original read found an owner but now there is none 3486d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor owned by '%s' on object of type '%s'" 3496d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " (where now the monitor appears unowned) on thread '%s'", 350ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes found_owner_string.c_str(), 351ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes PrettyTypeOf(o).c_str(), 352ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string.c_str()); 3536d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 3546d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 3556d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (found_owner == NULL) { 3566d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers // Race: originally there was no owner, there is now 3576d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor owned by '%s' on object of type '%s'" 3586d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " (originally believed to be unowned) on thread '%s'", 359ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes current_owner_string.c_str(), 360ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes PrettyTypeOf(o).c_str(), 361ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string.c_str()); 3626d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 3636d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (found_owner != current_owner) { 3646d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers // Race: originally found and current owner have changed 3656d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor originally owned by '%s' (now" 3666d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " owned by '%s') on object of type '%s' on thread '%s'", 367ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes found_owner_string.c_str(), 368ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes current_owner_string.c_str(), 369ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes PrettyTypeOf(o).c_str(), 370ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string.c_str()); 3716d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 3726d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor owned by '%s' on object of type '%s'" 3736d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " on thread '%s", 374ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes current_owner_string.c_str(), 375ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes PrettyTypeOf(o).c_str(), 376ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string.c_str()); 3776d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 3786d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 3796d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 3805f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 3815f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 382d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogersbool Monitor::Unlock(Thread* self) { 3835f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 384d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(self, monitor_lock_); 3856d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers Thread* owner = owner_; 3866d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (owner == self) { 3875f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // We own the monitor, so nobody else can be in here. 3885f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (lock_count_ == 0) { 3895f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes owner_ = NULL; 39033dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_method_ = NULL; 3910399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers locking_dex_pc_ = 0; 392d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Wake a contender. 393d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_contenders_.Signal(self); 3945f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 3955f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes --lock_count_; 3965f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 3975f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 3985f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // We don't own this, so we're not allowed to unlock it. 3995f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // The JNI spec says that we should throw IllegalMonitorStateException 4005f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // in this case. 4014cba0d979a11f955e6ec3c0f1bf61478af7aa810Hiroshi Yamauchi FailedUnlock(GetObject(), self, owner, this); 4025f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return false; 4035f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 4045f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return true; 4055f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 4065f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4075f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 4085f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Wait on a monitor until timeout, interrupt, or notification. Used for 4095f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Object.wait() and (somewhat indirectly) Thread.sleep() and Thread.join(). 4105f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 4115f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * If another thread calls Thread.interrupt(), we throw InterruptedException 4125f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * and return immediately if one of the following are true: 4135f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - blocked in wait(), wait(long), or wait(long, int) methods of Object 4145f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - blocked in join(), join(long), or join(long, int) methods of Thread 4155f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - blocked in sleep(long), or sleep(long, int) methods of Thread 4165f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Otherwise, we set the "interrupted" flag. 4175f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 4185f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Checks to make sure that "ns" is in the range 0-999999 4195f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * (i.e. fractions of a millisecond) and throws the appropriate 4205f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * exception if it isn't. 4215f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 4225f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The spec allows "spurious wakeups", and recommends that all code using 4235f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Object.wait() do so in a loop. This appears to derive from concerns 4245f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * about pthread_cond_wait() on multiprocessor systems. Some commentary 4255f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * on the web casts doubt on whether these can/should occur. 4265f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 4275f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Since we're allowed to wake up "early", we clamp extremely long durations 4285f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * to return at the end of the 32-bit time epoch. 4295f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 4304cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughesvoid Monitor::Wait(Thread* self, int64_t ms, int32_t ns, 4314cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes bool interruptShouldThrow, ThreadState why) { 4325f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 4334cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes DCHECK(why == kTimedWaiting || why == kWaiting || why == kSleeping); 4345f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 435d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Lock(self); 436d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers 4375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Make sure that we hold the lock. 4385f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (owner_ != self) { 439d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Unlock(self); 4401af6a1fa35ff7dc0a5c653f19dbc8a91c914aa42Elena Sayapina ThrowIllegalMonitorStateExceptionF("object not locked by thread before wait()"); 4415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 4425f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 4434cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes 444df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes // We need to turn a zero-length timed wait into a regular wait because 445df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes // Object.wait(0, 0) is defined as Object.wait(0), which is defined as Object.wait(). 446df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes if (why == kTimedWaiting && (ms == 0 && ns == 0)) { 447df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes why = kWaiting; 448df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes } 449df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes 4505f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Enforce the timeout range. 4515f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (ms < 0 || ns < 0 || ns > 999999) { 4521af6a1fa35ff7dc0a5c653f19dbc8a91c914aa42Elena Sayapina monitor_lock_.Unlock(self); 45362d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers ThrowLocation throw_location = self->GetCurrentLocationForThrow(); 45462d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers self->ThrowNewExceptionF(throw_location, "Ljava/lang/IllegalArgumentException;", 455ef7d42fca18c16fbaf103822ad16f23246e2905dIan Rogers "timeout arguments out of range: ms=%" PRId64 " ns=%d", ms, ns); 4565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 4575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 4585f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 4605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Add ourselves to the set of threads waiting on this monitor, and 4615f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * release our hold. We need to let it go even if we're a few levels 4625f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * deep in a recursive lock, and we need to restore that later. 4635f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 4645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * We append to the wait set ahead of clearing the count and owner 4655f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * fields so the subroutine can check that the calling thread owns 4665f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * the monitor. Aside from that, the order of member updates is 4675f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * not order sensitive as we hold the pthread mutex. 4685f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 4695f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes AppendToWaitSet(self); 470440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier ++num_waiters_; 4710399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers int prev_lock_count = lock_count_; 4725f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes lock_count_ = 0; 4735f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes owner_ = NULL; 474ef7d42fca18c16fbaf103822ad16f23246e2905dIan Rogers mirror::ArtMethod* saved_method = locking_method_; 47533dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_method_ = NULL; 4760399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers uintptr_t saved_dex_pc = locking_dex_pc_; 4770399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers locking_dex_pc_ = 0; 4785f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 4804cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes * Update thread state. If the GC wakes up, it'll ignore us, knowing 4815f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * that we won't touch any references in this state, and we'll check 4825f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * our suspend mode before we transition out. 4835f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 4844cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes self->TransitionFromRunnableToSuspended(why); 4855f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 486b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes bool was_interrupted = false; 48700f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers { 48800f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Pseudo-atomically wait on self's wait_cond_ and release the monitor lock. 489dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers MutexLock mu(self, *self->GetWaitMutex()); 4905f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 49100f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Set wait_monitor_ to the monitor object we will be waiting on. When wait_monitor_ is 49200f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // non-NULL a notifying or interrupting thread must signal the thread's wait_cond_ to wake it 49300f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // up. 494dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers DCHECK(self->GetWaitMonitor() == nullptr); 495dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->SetWaitMonitor(this); 4965f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 49700f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Release the monitor lock. 498d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_contenders_.Signal(self); 499d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Unlock(self); 50000f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers 501b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes // Handle the case where the thread was interrupted before we called wait(). 502dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers if (self->IsInterruptedLocked()) { 503b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes was_interrupted = true; 50400f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } else { 50500f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Wait for a notification or a timeout to occur. 5064cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes if (why == kWaiting) { 507dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->GetWaitConditionVariable()->Wait(self); 50800f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } else { 5094cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes DCHECK(why == kTimedWaiting || why == kSleeping) << why; 510dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->GetWaitConditionVariable()->TimedWait(self, ms, ns); 51100f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } 512dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers if (self->IsInterruptedLocked()) { 513b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes was_interrupted = true; 51400f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } 515dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->SetInterruptedLocked(false); 51600f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } 5175f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5185f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 51900f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Set self->status back to kRunnable, and self-suspend if needed. 52000f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers self->TransitionFromSuspendedToRunnable(); 5215f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 522b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes { 523b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes // We reset the thread's wait_monitor_ field after transitioning back to runnable so 524b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes // that a thread in a waiting/sleeping state has a non-null wait_monitor_ for debugging 525b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes // and diagnostic purposes. (If you reset this earlier, stack dumps will claim that threads 526b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes // are waiting on "null".) 527dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers MutexLock mu(self, *self->GetWaitMutex()); 528dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers DCHECK(self->GetWaitMonitor() != nullptr); 529dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->SetWaitMonitor(nullptr); 530b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes } 531b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes 532d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Re-acquire the monitor and lock. 53300f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers Lock(self); 534d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Lock(self); 535dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->GetWaitMutex()->AssertNotHeld(self); 5365f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 5385f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * We remove our thread from wait set after restoring the count 5395f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * and owner fields so the subroutine can check that the calling 5405f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * thread owns the monitor. Aside from that, the order of member 5415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * updates is not order sensitive as we hold the pthread mutex. 5425f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 5435f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes owner_ = self; 5440399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers lock_count_ = prev_lock_count; 5450399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers locking_method_ = saved_method; 5460399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers locking_dex_pc_ = saved_dex_pc; 547440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier --num_waiters_; 5485f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes RemoveFromWaitSet(self); 5495f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5501af6a1fa35ff7dc0a5c653f19dbc8a91c914aa42Elena Sayapina monitor_lock_.Unlock(self); 5511af6a1fa35ff7dc0a5c653f19dbc8a91c914aa42Elena Sayapina 552b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes if (was_interrupted) { 5535f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 5545f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * We were interrupted while waiting, or somebody interrupted an 5555f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * un-interruptible thread earlier and we're bailing out immediately. 5565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 5575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The doc sayeth: "The interrupted status of the current thread is 5585f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * cleared when this exception is thrown." 5595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 56000f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers { 561dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers MutexLock mu(self, *self->GetWaitMutex()); 562dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->SetInterruptedLocked(false); 56300f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } 5645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (interruptShouldThrow) { 56562d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers ThrowLocation throw_location = self->GetCurrentLocationForThrow(); 56662d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers self->ThrowNewException(throw_location, "Ljava/lang/InterruptedException;", NULL); 5675f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5685f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5695f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 5705f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5715f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::Notify(Thread* self) { 5725f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 573d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(self, monitor_lock_); 5745f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Make sure that we hold the lock. 5755f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (owner_ != self) { 5766d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notify()"); 5775f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 5785f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Signal the first waiting thread in the wait set. 5805f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes while (wait_set_ != NULL) { 5815f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* thread = wait_set_; 582dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers wait_set_ = thread->GetWaitNext(); 583dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers thread->SetWaitNext(nullptr); 5845f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5855f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Check to see if the thread is still waiting. 586dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers MutexLock mu(self, *thread->GetWaitMutex()); 587dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers if (thread->GetWaitMonitor() != nullptr) { 588dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers thread->GetWaitConditionVariable()->Signal(self); 5895f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 5905f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5915f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5925f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 5935f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5945f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::NotifyAll(Thread* self) { 5955f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 596d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(self, monitor_lock_); 5975f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Make sure that we hold the lock. 5985f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (owner_ != self) { 5996d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notifyAll()"); 6005f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 6015f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6025f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Signal all threads in the wait set. 6035f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes while (wait_set_ != NULL) { 6045f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* thread = wait_set_; 605dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers wait_set_ = thread->GetWaitNext(); 606dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers thread->SetWaitNext(nullptr); 6075f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thread->Notify(); 6085f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6095f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 6105f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 611590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartierbool Monitor::Deflate(Thread* self, mirror::Object* obj) { 612590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier DCHECK(obj != nullptr); 6134d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier // Don't need volatile since we only deflate with mutators suspended. 6144d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier LockWord lw(obj->GetLockWord(false)); 615590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // If the lock isn't an inflated monitor, then we don't need to deflate anything. 616590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier if (lw.GetState() == LockWord::kFatLocked) { 617590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier Monitor* monitor = lw.FatLockMonitor(); 618440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier DCHECK(monitor != nullptr); 619590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier MutexLock mu(self, monitor->monitor_lock_); 620440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier // Can't deflate if we have anybody waiting on the CV. 621440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier if (monitor->num_waiters_ > 0) { 622440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier return false; 623440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier } 624590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier Thread* owner = monitor->owner_; 625590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier if (owner != nullptr) { 626590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // Can't deflate if we are locked and have a hash code. 627590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier if (monitor->HasHashCode()) { 628590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier return false; 629590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 630590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // Can't deflate if our lock count is too high. 631590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier if (monitor->lock_count_ > LockWord::kThinLockMaxCount) { 632590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier return false; 633590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 634590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // Deflate to a thin lock. 6354d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier obj->SetLockWord(LockWord::FromThinLockId(owner->GetThreadId(), monitor->lock_count_), false); 6364d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier VLOG(monitor) << "Deflated " << obj << " to thin lock " << owner->GetTid() << " / " 6374d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier << monitor->lock_count_; 638590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } else if (monitor->HasHashCode()) { 6394d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier obj->SetLockWord(LockWord::FromHashCode(monitor->GetHashCode()), false); 640440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier VLOG(monitor) << "Deflated " << obj << " to hash monitor " << monitor->GetHashCode(); 641590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } else { 642590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // No lock and no hash, just put an empty lock word inside the object. 6434d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier obj->SetLockWord(LockWord(), false); 644440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier VLOG(monitor) << "Deflated" << obj << " to empty lock word"; 645590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 646590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // The monitor is deflated, mark the object as nullptr so that we know to delete it during the 647590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // next GC. 64894f7b49578b6aaa80de8ffed230648d601393905Hiroshi Yamauchi monitor->obj_ = GcRoot<mirror::Object>(nullptr); 649590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 650590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier return true; 651590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier} 652590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier 653ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartiervoid Monitor::Inflate(Thread* self, Thread* owner, mirror::Object* obj, int32_t hash_code) { 65474240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe DCHECK(self != nullptr); 65574240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe DCHECK(obj != nullptr); 6565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Allocate and acquire a new monitor. 65774240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe Monitor* m = MonitorPool::CreateMonitor(self, owner, obj, hash_code); 65874240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe DCHECK(m != nullptr); 659d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (m->Install(self)) { 66086ab7912423f63541073af5c487b509e9b2b5420Haifeng Li if (owner != nullptr) { 66186ab7912423f63541073af5c487b509e9b2b5420Haifeng Li VLOG(monitor) << "monitor: thread" << owner->GetThreadId() 66274240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe << " created monitor " << m << " for object " << obj; 66386ab7912423f63541073af5c487b509e9b2b5420Haifeng Li } else { 66486ab7912423f63541073af5c487b509e9b2b5420Haifeng Li VLOG(monitor) << "monitor: Inflate with hashcode " << hash_code 66574240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe << " created monitor " << m << " for object " << obj; 66686ab7912423f63541073af5c487b509e9b2b5420Haifeng Li } 66774240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe Runtime::Current()->GetMonitorList()->Add(m); 6684d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier CHECK_EQ(obj->GetLockWord(true).GetState(), LockWord::kFatLocked); 66974240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe } else { 67074240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe MonitorPool::ReleaseMonitor(self, m); 671ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 672ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier} 673ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier 6740cd81352a7c06e381951cea1b104fd73516f4341Mathieu Chartiervoid Monitor::InflateThinLocked(Thread* self, Handle<mirror::Object> obj, LockWord lock_word, 675ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier uint32_t hash_code) { 676ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier DCHECK_EQ(lock_word.GetState(), LockWord::kThinLocked); 677ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier uint32_t owner_thread_id = lock_word.ThinLockOwner(); 678ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier if (owner_thread_id == self->GetThreadId()) { 679ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // We own the monitor, we can easily inflate it. 680eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier Inflate(self, self, obj.Get(), hash_code); 681ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } else { 682ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier ThreadList* thread_list = Runtime::Current()->GetThreadList(); 683ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Suspend the owner, inflate. First change to blocked and give up mutator_lock_. 684eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier self->SetMonitorEnterObject(obj.Get()); 685a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier bool timed_out; 686a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier Thread* owner; 687a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier { 688a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier ScopedThreadStateChange tsc(self, kBlocked); 689f3d874c60ee3ada19ce26a5c4e532312b6f3a9e9Ian Rogers // Take suspend thread lock to avoid races with threads trying to suspend this one. 690f3d874c60ee3ada19ce26a5c4e532312b6f3a9e9Ian Rogers MutexLock mu(self, *Locks::thread_list_suspend_thread_lock_); 691a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier owner = thread_list->SuspendThreadByThreadId(owner_thread_id, false, &timed_out); 692a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier } 693a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier if (owner != nullptr) { 694a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier // We succeeded in suspending the thread, check the lock's status didn't change. 695a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier lock_word = obj->GetLockWord(true); 696a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier if (lock_word.GetState() == LockWord::kThinLocked && 697a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier lock_word.ThinLockOwner() == owner_thread_id) { 698a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier // Go ahead and inflate the lock. 699a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier Inflate(self, owner, obj.Get(), hash_code); 700ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 701a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier thread_list->Resume(owner, false); 702ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 703dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->SetMonitorEnterObject(nullptr); 704d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 7055f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 7065f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 707719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers// Fool annotalysis into thinking that the lock on obj is acquired. 708719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogersstatic mirror::Object* FakeLock(mirror::Object* obj) 709719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers EXCLUSIVE_LOCK_FUNCTION(obj) NO_THREAD_SAFETY_ANALYSIS { 710719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers return obj; 711719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers} 712719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers 713719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers// Fool annotalysis into thinking that the lock on obj is release. 714719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogersstatic mirror::Object* FakeUnlock(mirror::Object* obj) 715719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers UNLOCK_FUNCTION(obj) NO_THREAD_SAFETY_ANALYSIS { 716719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers return obj; 717719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers} 718719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers 719e7e8a5fea2d852cccc840fa046151a16627f26cdMathieu Chartiermirror::Object* Monitor::MonitorEnter(Thread* self, mirror::Object* obj) { 7204681c809ba35d50fab92c592ce8d2c7f8b2731f7Elliott Hughes DCHECK(self != NULL); 7214681c809ba35d50fab92c592ce8d2c7f8b2731f7Elliott Hughes DCHECK(obj != NULL); 722719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers obj = FakeLock(obj); 723d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t thread_id = self->GetThreadId(); 724d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers size_t contention_count = 0; 725eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier StackHandleScope<1> hs(self); 726eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier Handle<mirror::Object> h_obj(hs.NewHandle(obj)); 727d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers while (true) { 728eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier LockWord lock_word = h_obj->GetLockWord(true); 729d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 730d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: { 731d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LockWord thin_locked(LockWord::FromThinLockId(thread_id, 0)); 732228602f562f1d130d06e60a98752d99c2d467d6aIan Rogers if (h_obj->CasLockWordWeakSequentiallyConsistent(lock_word, thin_locked)) { 7333035961cb41865b80b927546be0c708b6389cec6Hans Boehm // CasLockWord enforces more than the acquire ordering we need here. 734eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier return h_obj.Get(); // Success! 735d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 736d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers continue; // Go again. 7375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 738d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: { 739d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t owner_thread_id = lock_word.ThinLockOwner(); 740d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (owner_thread_id == thread_id) { 741d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // We own the lock, increase the recursion count. 742d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t new_count = lock_word.ThinLockCount() + 1; 743d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (LIKELY(new_count <= LockWord::kThinLockMaxCount)) { 744d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LockWord thin_locked(LockWord::FromThinLockId(thread_id, new_count)); 745eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier h_obj->SetLockWord(thin_locked, true); 746eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier return h_obj.Get(); // Success! 747d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 748d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // We'd overflow the recursion count, so inflate the monitor. 749eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier InflateThinLocked(self, h_obj, lock_word, 0); 750d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 751d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 752d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Contention. 753d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers contention_count++; 754ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier Runtime* runtime = Runtime::Current(); 755ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier if (contention_count <= runtime->GetMaxSpinsBeforeThinkLockInflation()) { 756b363f666883860d40823d5528df3c98c897f74f4Mathieu Chartier // TODO: Consider switching the thread state to kBlocked when we are yielding. 757251755cd511463260e60be98bf138b6aa1c14bf3Mathieu Chartier // Use sched_yield instead of NanoSleep since NanoSleep can wait much longer than the 758251755cd511463260e60be98bf138b6aa1c14bf3Mathieu Chartier // parameter you pass in. This can cause thread suspension to take excessively long 759b363f666883860d40823d5528df3c98c897f74f4Mathieu Chartier // and make long pauses. See b/16307460. 760251755cd511463260e60be98bf138b6aa1c14bf3Mathieu Chartier sched_yield(); 7615f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 762d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers contention_count = 0; 763eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier InflateThinLocked(self, h_obj, lock_word, 0); 7645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7655f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 766d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers continue; // Start from the beginning. 767d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 768d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 769d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 770d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers mon->Lock(self); 771eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier return h_obj.Get(); // Success! 7725f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 773719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers case LockWord::kHashCode: 774ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Inflate with the existing hashcode. 775eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier Inflate(self, nullptr, h_obj.Get(), lock_word.GetHashCode()); 776719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers continue; // Start from the beginning. 777590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier default: { 778590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier LOG(FATAL) << "Invalid monitor state " << lock_word.GetState(); 779eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier return h_obj.Get(); 780590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 7815f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7825f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7835f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 7845f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 7852dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersbool Monitor::MonitorExit(Thread* self, mirror::Object* obj) { 7865f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 7875f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(obj != NULL); 788719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers obj = FakeUnlock(obj); 7894d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier LockWord lock_word = obj->GetLockWord(true); 790eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier StackHandleScope<1> hs(self); 791eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier Handle<mirror::Object> h_obj(hs.NewHandle(obj)); 792d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 793ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: 794ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Fall-through. 795d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: 796eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier FailedUnlock(h_obj.Get(), self, nullptr, nullptr); 797d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return false; // Failure. 798d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: { 799d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t thread_id = self->GetThreadId(); 800d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t owner_thread_id = lock_word.ThinLockOwner(); 801d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (owner_thread_id != thread_id) { 802d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // TODO: there's a race here with the owner dying while we unlock. 803d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Thread* owner = 804d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Runtime::Current()->GetThreadList()->FindThreadByThreadId(lock_word.ThinLockOwner()); 805eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier FailedUnlock(h_obj.Get(), self, owner, nullptr); 806d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return false; // Failure. 8075f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 808d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // We own the lock, decrease the recursion count. 809d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (lock_word.ThinLockCount() != 0) { 810d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t new_count = lock_word.ThinLockCount() - 1; 811d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LockWord thin_locked(LockWord::FromThinLockId(thread_id, new_count)); 812eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier h_obj->SetLockWord(thin_locked, true); 813d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 814eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier h_obj->SetLockWord(LockWord(), true); 815d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 816d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return true; // Success! 8175f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 8185f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 819d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 820d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 821d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return mon->Unlock(self); 8225f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 823590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier default: { 824590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier LOG(FATAL) << "Invalid monitor state " << lock_word.GetState(); 825d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return false; 826590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 8275f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 8285f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 8295f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 8305f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 8315f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Object.wait(). Also called for class init. 8325f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 8332dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersvoid Monitor::Wait(Thread* self, mirror::Object *obj, int64_t ms, int32_t ns, 8344cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes bool interruptShouldThrow, ThreadState why) { 8354d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier DCHECK(self != nullptr); 8364d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier DCHECK(obj != nullptr); 8374d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier LockWord lock_word = obj->GetLockWord(true); 8386f22fc166ed6c11cad229bff442c064e704de101Ian Rogers while (lock_word.GetState() != LockWord::kFatLocked) { 8396f22fc166ed6c11cad229bff442c064e704de101Ian Rogers switch (lock_word.GetState()) { 8406f22fc166ed6c11cad229bff442c064e704de101Ian Rogers case LockWord::kHashCode: 8416f22fc166ed6c11cad229bff442c064e704de101Ian Rogers // Fall-through. 8426f22fc166ed6c11cad229bff442c064e704de101Ian Rogers case LockWord::kUnlocked: 843d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before wait()"); 844d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Failure. 8456f22fc166ed6c11cad229bff442c064e704de101Ian Rogers case LockWord::kThinLocked: { 8466f22fc166ed6c11cad229bff442c064e704de101Ian Rogers uint32_t thread_id = self->GetThreadId(); 8476f22fc166ed6c11cad229bff442c064e704de101Ian Rogers uint32_t owner_thread_id = lock_word.ThinLockOwner(); 8486f22fc166ed6c11cad229bff442c064e704de101Ian Rogers if (owner_thread_id != thread_id) { 8496f22fc166ed6c11cad229bff442c064e704de101Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before wait()"); 8506f22fc166ed6c11cad229bff442c064e704de101Ian Rogers return; // Failure. 8516f22fc166ed6c11cad229bff442c064e704de101Ian Rogers } else { 8526f22fc166ed6c11cad229bff442c064e704de101Ian Rogers // We own the lock, inflate to enqueue ourself on the Monitor. May fail spuriously so 8536f22fc166ed6c11cad229bff442c064e704de101Ian Rogers // re-load. 8546f22fc166ed6c11cad229bff442c064e704de101Ian Rogers Inflate(self, self, obj, 0); 8556f22fc166ed6c11cad229bff442c064e704de101Ian Rogers lock_word = obj->GetLockWord(true); 8566f22fc166ed6c11cad229bff442c064e704de101Ian Rogers } 8576f22fc166ed6c11cad229bff442c064e704de101Ian Rogers break; 8586f22fc166ed6c11cad229bff442c064e704de101Ian Rogers } 8596f22fc166ed6c11cad229bff442c064e704de101Ian Rogers case LockWord::kFatLocked: // Unreachable given the loop condition above. Fall-through. 8606f22fc166ed6c11cad229bff442c064e704de101Ian Rogers default: { 8616f22fc166ed6c11cad229bff442c064e704de101Ian Rogers LOG(FATAL) << "Invalid monitor state " << lock_word.GetState(); 8626f22fc166ed6c11cad229bff442c064e704de101Ian Rogers return; 863d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 864590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 8655f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 866d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 867d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers mon->Wait(self, ms, ns, interruptShouldThrow, why); 8685f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 8695f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 87013c479e7e9b62115fe0409e5273c1e976a1c09f9Ian Rogersvoid Monitor::DoNotify(Thread* self, mirror::Object* obj, bool notify_all) { 8714d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier DCHECK(self != nullptr); 8724d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier DCHECK(obj != nullptr); 8734d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier LockWord lock_word = obj->GetLockWord(true); 874d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 875ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: 876ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Fall-through. 877d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: 8786d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notify()"); 879d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Failure. 880d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: { 881d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t thread_id = self->GetThreadId(); 882d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t owner_thread_id = lock_word.ThinLockOwner(); 883d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (owner_thread_id != thread_id) { 884d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notify()"); 885d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Failure. 886d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 887d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // We own the lock but there's no Monitor and therefore no waiters. 888d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Success. 889d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 890d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 891d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 892d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 893d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (notify_all) { 894d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers mon->NotifyAll(self); 895d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 896d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers mon->Notify(self); 897d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 898d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Success. 8995f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 900590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier default: { 901590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier LOG(FATAL) << "Invalid monitor state " << lock_word.GetState(); 902590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier return; 903590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 9045f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 9055f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 9065f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 907d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogersuint32_t Monitor::GetLockOwnerThreadId(mirror::Object* obj) { 9084d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier DCHECK(obj != nullptr); 9094d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier LockWord lock_word = obj->GetLockWord(true); 910d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 911ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: 912ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Fall-through. 913d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: 914d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return ThreadList::kInvalidThreadId; 915d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: 916d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return lock_word.ThinLockOwner(); 917d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 918d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 919d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return mon->GetOwnerThreadId(); 9205f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 921590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier default: { 922d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LOG(FATAL) << "Unreachable"; 923d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return ThreadList::kInvalidThreadId; 924590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 9255f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 9265f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 9275f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 9288e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughesvoid Monitor::DescribeWait(std::ostream& os, const Thread* thread) { 929d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers // Determine the wait message and object we're waiting or blocked upon. 930d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers mirror::Object* pretty_object = nullptr; 931d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers const char* wait_message = nullptr; 932d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t lock_owner = ThreadList::kInvalidThreadId; 933d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers ThreadState state = thread->GetState(); 934b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes if (state == kWaiting || state == kTimedWaiting || state == kSleeping) { 935d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers wait_message = (state == kSleeping) ? " - sleeping on " : " - waiting on "; 936d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers Thread* self = Thread::Current(); 937d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers MutexLock mu(self, *thread->GetWaitMutex()); 938d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers Monitor* monitor = thread->GetWaitMonitor(); 939d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers if (monitor != nullptr) { 9404cba0d979a11f955e6ec3c0f1bf61478af7aa810Hiroshi Yamauchi pretty_object = monitor->GetObject(); 9418e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 94234e069606d6f1698cd3c33b39e72b79ae27e1c7bElliott Hughes } else if (state == kBlocked) { 943d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers wait_message = " - waiting to lock "; 944d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers pretty_object = thread->GetMonitorEnterObject(); 945d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers if (pretty_object != nullptr) { 946d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers lock_owner = pretty_object->GetLockOwnerThreadId(); 9478e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 9488e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 9498e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes 950d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers if (wait_message != nullptr) { 951d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers if (pretty_object == nullptr) { 952d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers os << wait_message << "an unknown object"; 953d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers } else { 9544d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier if ((pretty_object->GetLockWord(true).GetState() == LockWord::kThinLocked) && 955d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers Locks::mutator_lock_->IsExclusiveHeld(Thread::Current())) { 956d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers // Getting the identity hashcode here would result in lock inflation and suspension of the 957d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers // current thread, which isn't safe if this is the only runnable thread. 958d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers os << wait_message << StringPrintf("<@addr=0x%" PRIxPTR "> (a %s)", 959d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers reinterpret_cast<intptr_t>(pretty_object), 960d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers PrettyTypeOf(pretty_object).c_str()); 961d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers } else { 962d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers // - waiting on <0x6008c468> (a java.lang.Class<java.lang.ref.ReferenceQueue>) 963d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers os << wait_message << StringPrintf("<0x%08x> (a %s)", pretty_object->IdentityHashCode(), 964d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers PrettyTypeOf(pretty_object).c_str()); 965d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers } 966d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers } 967d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers // - waiting to lock <0x613f83d8> (a java.lang.Object) held by thread 5 968d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers if (lock_owner != ThreadList::kInvalidThreadId) { 969d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers os << " held by thread " << lock_owner; 970d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers } 971d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers os << "\n"; 9728e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 9738e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes} 9748e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes 9752dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersmirror::Object* Monitor::GetContendedMonitor(Thread* thread) { 976f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes // This is used to implement JDWP's ThreadReference.CurrentContendedMonitor, and has a bizarre 977f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes // definition of contended that includes a monitor a thread is trying to enter... 978dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers mirror::Object* result = thread->GetMonitorEnterObject(); 979d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (result == NULL) { 980d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // ...but also a monitor that the thread is waiting on. 981dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers MutexLock mu(Thread::Current(), *thread->GetWaitMutex()); 982dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers Monitor* monitor = thread->GetWaitMonitor(); 983f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes if (monitor != NULL) { 984d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers result = monitor->GetObject(); 985f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes } 986f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes } 987d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return result; 988f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes} 989f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes 9902dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersvoid Monitor::VisitLocks(StackVisitor* stack_visitor, void (*callback)(mirror::Object*, void*), 991760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe void* callback_context, bool abort_on_failure) { 992ea46f950e7a51585db293cd7f047de190a482414Brian Carlstrom mirror::ArtMethod* m = stack_visitor->GetMethod(); 99308fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes CHECK(m != NULL); 99408fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 99508fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes // Native methods are an easy special case. 99608fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes // TODO: use the JNI implementation's table of explicit MonitorEnter calls and dump those too. 99708fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes if (m->IsNative()) { 99808fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes if (m->IsSynchronized()) { 999eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier mirror::Object* jni_this = stack_visitor->GetCurrentHandleScope()->GetReference(0); 10004993bbc8eda377804e585efd918f8ab9d9eab7d4Elliott Hughes callback(jni_this, callback_context); 100108fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 100208fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes return; 100308fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 100408fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 100561f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao // Proxy methods should not be synchronized. 100661f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao if (m->IsProxyMethod()) { 100761f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao CHECK(!m->IsSynchronized()); 100861f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao return; 100961f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao } 101061f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao 101108fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes // Is there any reason to believe there's any synchronization in this method? 1012bfd9a4378eacaf2dc2bbe05ad48c5164fc93c9feMathieu Chartier const DexFile::CodeItem* code_item = m->GetCodeItem(); 1013caf7654a0e6c76c7489970b1a246fccf220f9982Elliott Hughes CHECK(code_item != NULL) << PrettyMethod(m); 101408fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes if (code_item->tries_size_ == 0) { 10157934ac288acfb2552bb0b06ec1f61e5820d924a4Brian Carlstrom return; // No "tries" implies no synchronization, so no held locks to report. 101608fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 101708fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 1018760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe // Get the dex pc. If abort_on_failure is false, GetDexPc will not abort in the case it cannot 1019760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe // find the dex pc, and instead return kDexNoIndex. Then bail out, as it indicates we have an 1020760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe // inconsistent stack anyways. 1021760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe uint32_t dex_pc = stack_visitor->GetDexPc(abort_on_failure); 1022760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe if (!abort_on_failure && dex_pc == DexFile::kDexNoIndex) { 1023760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe LOG(ERROR) << "Could not find dex_pc for " << PrettyMethod(m); 1024760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe return; 1025760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe } 1026760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe 102780537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes // Ask the verifier for the dex pcs of all the monitor-enter instructions corresponding to 102880537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes // the locks held in this stack frame. 102980537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes std::vector<uint32_t> monitor_enter_dex_pcs; 1030760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe verifier::MethodVerifier::FindLocksAtDexPc(m, dex_pc, &monitor_enter_dex_pcs); 103180537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes if (monitor_enter_dex_pcs.empty()) { 103280537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes return; 103380537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes } 103408fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 103580537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes for (size_t i = 0; i < monitor_enter_dex_pcs.size(); ++i) { 103680537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes // The verifier works in terms of the dex pcs of the monitor-enter instructions. 103780537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes // We want the registers used by those instructions (so we can read the values out of them). 103880537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes uint32_t dex_pc = monitor_enter_dex_pcs[i]; 103980537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes uint16_t monitor_enter_instruction = code_item->insns_[dex_pc]; 104008fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 104180537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes // Quick sanity check. 104280537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes if ((monitor_enter_instruction & 0xff) != Instruction::MONITOR_ENTER) { 104380537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes LOG(FATAL) << "expected monitor-enter @" << dex_pc << "; was " 104480537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes << reinterpret_cast<void*>(monitor_enter_instruction); 104508fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 104680537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes 104780537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes uint16_t monitor_register = ((monitor_enter_instruction >> 8) & 0xff); 10482dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogers mirror::Object* o = reinterpret_cast<mirror::Object*>(stack_visitor->GetVReg(m, monitor_register, 10492dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogers kReferenceVReg)); 10504993bbc8eda377804e585efd918f8ab9d9eab7d4Elliott Hughes callback(o, callback_context); 105108fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 105208fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes} 105308fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 1054d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogersbool Monitor::IsValidLockWord(LockWord lock_word) { 1055d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 1056d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: 1057d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Nothing to check. 1058d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return true; 1059d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: 1060d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Basic sanity check of owner. 1061d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return lock_word.ThinLockOwner() != ThreadList::kInvalidThreadId; 1062d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 1063d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Check the monitor appears in the monitor list. 1064d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 1065d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MonitorList* list = Runtime::Current()->GetMonitorList(); 1066d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(Thread::Current(), list->monitor_list_lock_); 1067d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers for (Monitor* list_mon : list->list_) { 1068d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (mon == list_mon) { 1069d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return true; // Found our monitor. 1070d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 10717dfb28c066159e6cde8181720f0c451a700ef966Ian Rogers } 1072d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return false; // Fail - unowned monitor in an object. 10737dfb28c066159e6cde8181720f0c451a700ef966Ian Rogers } 1074ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: 1075ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier return true; 1076d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers default: 1077d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LOG(FATAL) << "Unreachable"; 1078d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return false; 10797dfb28c066159e6cde8181720f0c451a700ef966Ian Rogers } 10807dfb28c066159e6cde8181720f0c451a700ef966Ian Rogers} 10817dfb28c066159e6cde8181720f0c451a700ef966Ian Rogers 1082ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartierbool Monitor::IsLocked() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1083ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier MutexLock mu(Thread::Current(), monitor_lock_); 1084ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier return owner_ != nullptr; 1085ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier} 1086ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier 1087ef7d42fca18c16fbaf103822ad16f23246e2905dIan Rogersvoid Monitor::TranslateLocation(mirror::ArtMethod* method, uint32_t dex_pc, 1088d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers const char** source_file, uint32_t* line_number) const { 108933dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao // If method is null, location is unknown 109033dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao if (method == NULL) { 1091d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers *source_file = ""; 1092d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers *line_number = 0; 109333dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao return; 109433dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao } 1095bfd9a4378eacaf2dc2bbe05ad48c5164fc93c9feMathieu Chartier *source_file = method->GetDeclaringClassSourceFile(); 1096d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (*source_file == NULL) { 1097d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers *source_file = ""; 1098d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 1099bfd9a4378eacaf2dc2bbe05ad48c5164fc93c9feMathieu Chartier *line_number = method->GetLineNumFromDexPC(dex_pc); 1100d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers} 1101d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers 1102d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogersuint32_t Monitor::GetOwnerThreadId() { 1103d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(Thread::Current(), monitor_lock_); 1104d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Thread* owner = owner_; 1105d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (owner != NULL) { 1106d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return owner->GetThreadId(); 1107d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 1108d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return ThreadList::kInvalidThreadId; 110912c51e3e5a8b5655351539618f1cf2331f52d1abElliott Hughes } 111033dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao} 111133dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao 1112c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu ChartierMonitorList::MonitorList() 1113440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier : allow_new_monitors_(true), monitor_list_lock_("MonitorList lock", kMonitorListLock), 1114c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier monitor_add_condition_("MonitorList disallow condition", monitor_list_lock_) { 1115c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 1116c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 1117c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott HughesMonitorList::~MonitorList() { 111874240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe Thread* self = Thread::Current(); 111974240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe MutexLock mu(self, monitor_list_lock_); 112074240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe // Release all monitors to the pool. 112174240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe // TODO: Is it an invariant that *all* open monitors are in the list? Then we could 112274240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe // clear faster in the pool. 112374240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe MonitorPool::ReleaseMonitors(self, &list_); 1124c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 1125c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 1126c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartiervoid MonitorList::DisallowNewMonitors() { 112750b35e2fd1a68cd1240e4a9d9f363e11764957d1Ian Rogers MutexLock mu(Thread::Current(), monitor_list_lock_); 1128c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier allow_new_monitors_ = false; 1129c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier} 1130c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier 1131c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartiervoid MonitorList::AllowNewMonitors() { 1132c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier Thread* self = Thread::Current(); 1133c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier MutexLock mu(self, monitor_list_lock_); 1134c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier allow_new_monitors_ = true; 1135c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier monitor_add_condition_.Broadcast(self); 1136c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier} 1137c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier 1138c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartiervoid MonitorList::Add(Monitor* m) { 1139c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier Thread* self = Thread::Current(); 1140c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier MutexLock mu(self, monitor_list_lock_); 1141c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier while (UNLIKELY(!allow_new_monitors_)) { 1142c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier monitor_add_condition_.WaitHoldingLocks(self); 1143c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier } 1144c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes list_.push_front(m); 1145c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 1146c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 114783c8ee000d525017ead8753fce6bc1020249b96aMathieu Chartiervoid MonitorList::SweepMonitorList(IsMarkedCallback* callback, void* arg) { 114874240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe Thread* self = Thread::Current(); 114974240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe MutexLock mu(self, monitor_list_lock_); 115002e25119b15a6f619f17db99f5d05124a5807ff3Mathieu Chartier for (auto it = list_.begin(); it != list_.end(); ) { 1151c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes Monitor* m = *it; 11524cba0d979a11f955e6ec3c0f1bf61478af7aa810Hiroshi Yamauchi // Disable the read barrier in GetObject() as this is called by GC. 11534cba0d979a11f955e6ec3c0f1bf61478af7aa810Hiroshi Yamauchi mirror::Object* obj = m->GetObject<kWithoutReadBarrier>(); 1154590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // The object of a monitor can be null if we have deflated it. 115583c8ee000d525017ead8753fce6bc1020249b96aMathieu Chartier mirror::Object* new_obj = obj != nullptr ? callback(obj, arg) : nullptr; 11566aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier if (new_obj == nullptr) { 11576aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier VLOG(monitor) << "freeing monitor " << m << " belonging to unmarked object " 11584cba0d979a11f955e6ec3c0f1bf61478af7aa810Hiroshi Yamauchi << obj; 115974240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe MonitorPool::ReleaseMonitor(self, m); 1160c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes it = list_.erase(it); 1161c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes } else { 11626aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier m->SetObject(new_obj); 1163c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes ++it; 1164c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes } 1165c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes } 1166c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 1167c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 116848ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartierstruct MonitorDeflateArgs { 116948ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier MonitorDeflateArgs() : self(Thread::Current()), deflate_count(0) {} 117048ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier Thread* const self; 117148ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier size_t deflate_count; 117248ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier}; 117348ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier 1174440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartierstatic mirror::Object* MonitorDeflateCallback(mirror::Object* object, void* arg) 1175440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 117648ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier MonitorDeflateArgs* args = reinterpret_cast<MonitorDeflateArgs*>(arg); 117748ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier if (Monitor::Deflate(args->self, object)) { 11784d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier DCHECK_NE(object->GetLockWord(true).GetState(), LockWord::kFatLocked); 117948ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier ++args->deflate_count; 1180440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier // If we deflated, return nullptr so that the monitor gets removed from the array. 1181440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier return nullptr; 1182440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier } 1183440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier return object; // Monitor was not deflated. 1184440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier} 1185440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier 118648ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartiersize_t MonitorList::DeflateMonitors() { 118748ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier MonitorDeflateArgs args; 118848ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier Locks::mutator_lock_->AssertExclusiveHeld(args.self); 118948ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier SweepMonitorList(MonitorDeflateCallback, &args); 119048ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier return args.deflate_count; 1191440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier} 1192440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier 1193d9c4fc94fa618617f94e1de9af5f034549100753Ian RogersMonitorInfo::MonitorInfo(mirror::Object* obj) : owner_(NULL), entry_count_(0) { 11944d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier DCHECK(obj != nullptr); 11954d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier LockWord lock_word = obj->GetLockWord(true); 1196d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 1197d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: 1198ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Fall-through. 1199590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier case LockWord::kForwardingAddress: 1200590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // Fall-through. 1201ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: 1202d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers break; 1203d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: 1204d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers owner_ = Runtime::Current()->GetThreadList()->FindThreadByThreadId(lock_word.ThinLockOwner()); 1205d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers entry_count_ = 1 + lock_word.ThinLockCount(); 1206d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Thin locks have no waiters. 1207d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers break; 1208d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 1209d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 1210d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers owner_ = mon->owner_; 1211d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers entry_count_ = 1 + mon->lock_count_; 1212dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers for (Thread* waiter = mon->wait_set_; waiter != NULL; waiter = waiter->GetWaitNext()) { 1213d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers waiters_.push_back(waiter); 1214d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 1215d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers break; 1216f327e07b37e349b1ec5eaad6dc294a9b7a081d20Elliott Hughes } 1217f327e07b37e349b1ec5eaad6dc294a9b7a081d20Elliott Hughes } 1218f327e07b37e349b1ec5eaad6dc294a9b7a081d20Elliott Hughes} 1219f327e07b37e349b1ec5eaad6dc294a9b7a081d20Elliott Hughes 12205f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} // namespace art 1221