monitor.cc revision 9728f91a63016136261231ff5213bde703bd27b6
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" 316d4d9fcb4f01e287ee29e81cd1c941ee5d11d379Ian Rogers#include "object_utils.h" 3200f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers#include "scoped_thread_state_change.h" 335f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#include "thread.h" 348e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes#include "thread_list.h" 3508fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes#include "verifier/method_verifier.h" 36044288fb8f69e154862763a6b3bfea2bac1b397eElliott Hughes#include "well_known_classes.h" 375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 385f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesnamespace art { 395f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 405f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 41d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * Every Object has a monitor associated with it, but not every Object is actually locked. Even 42d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * the ones that are locked do not need a full-fledged monitor until a) there is actual contention 43d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * or b) wait() is called on the Object. 445f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 45d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * For Android, we have implemented a scheme similar to the one described in Bacon et al.'s 46d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * "Thin locks: featherweight synchronization for Java" (ACM 1998). Things are even easier for us, 47d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * though, because we have a full 32 bits to work with. 485f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 49d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * The two states of an Object's lock are referred to as "thin" and "fat". A lock may transition 50d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * from the "thin" state to the "fat" state and this transition is referred to as inflation. Once 51d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * a lock has been inflated it remains in the "fat" state indefinitely. 525f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 53d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * The lock value itself is stored in mirror::Object::monitor_ and the representation is described 54d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * in the LockWord value type. 5554e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes * 565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Monitors provide: 575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - mutually exclusive access to resources 585f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - a way for multiple threads to wait for notification 595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * In effect, they fill the role of both mutexes and condition variables. 615f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 62d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * Only one thread can own the monitor at any time. There may be several threads waiting on it 63d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * (the wait call unlocks it). One or more waiting threads may be getting interrupted or notified 64d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * at any given time. 655f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 6654e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes 67fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughesbool (*Monitor::is_sensitive_thread_hook_)() = NULL; 68fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughesuint32_t Monitor::lock_profiling_threshold_ = 0; 6932d6e1e5654433d7eadede89e1c770b2c839aee9Elliott Hughes 70fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughesbool Monitor::IsSensitiveThread() { 71fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes if (is_sensitive_thread_hook_ != NULL) { 72fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes return (*is_sensitive_thread_hook_)(); 73fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 74fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes return false; 75fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes} 76fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes 774dd9b4d95eec9db5338fb9bf132f9bb8facf6cf4Elliott Hughesvoid Monitor::Init(uint32_t lock_profiling_threshold, bool (*is_sensitive_thread_hook)()) { 78fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes lock_profiling_threshold_ = lock_profiling_threshold; 79fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes is_sensitive_thread_hook_ = is_sensitive_thread_hook; 8032d6e1e5654433d7eadede89e1c770b2c839aee9Elliott Hughes} 8132d6e1e5654433d7eadede89e1c770b2c839aee9Elliott Hughes 82ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu ChartierMonitor::Monitor(Thread* owner, mirror::Object* obj, uint32_t hash_code) 8300f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers : monitor_lock_("a monitor lock", kMonitorLock), 84d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_contenders_("monitor contenders", monitor_lock_), 8500f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers owner_(owner), 865f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes lock_count_(0), 875f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes obj_(obj), 885f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wait_set_(NULL), 89ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier hash_code_(hash_code), 9033dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_method_(NULL), 910399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers locking_dex_pc_(0) { 92d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // We should only inflate a lock if the owner is ourselves or suspended. This avoids a race 93d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // with the owner unlocking the thin-lock. 94ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier CHECK(owner == nullptr || owner == Thread::Current() || owner->IsSuspended()); 95ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // The identity hash code is set for the life time of the monitor. 96d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers} 97d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers 98d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogersbool Monitor::Install(Thread* self) { 99d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(self, monitor_lock_); // Uncontended mutex acquisition as monitor isn't yet public. 100ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier CHECK(owner_ == nullptr || owner_ == self || owner_->IsSuspended()); 10100f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Propagate the lock state. 102ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier LockWord lw(obj_->GetLockWord()); 103ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier switch (lw.GetState()) { 104ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kThinLocked: { 105ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier CHECK_EQ(owner_->GetThreadId(), lw.ThinLockOwner()); 106ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier lock_count_ = lw.ThinLockCount(); 107ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier break; 108ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 109ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: { 110ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier CHECK_EQ(hash_code_, lw.GetHashCode()); 111ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier break; 112ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 113ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kFatLocked: { 114ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // The owner_ is suspended but another thread beat us to install a monitor. 115ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier return false; 116ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 117ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kUnlocked: { 118ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier LOG(FATAL) << "Inflating unlocked lock word"; 119ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier break; 120ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 121d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 122d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LockWord fat(this); 123d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Publish the updated lock word, which may race with other threads. 124ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier bool success = obj_->CasLockWord(lw, fat); 12500f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Lock profiling. 1269728f91a63016136261231ff5213bde703bd27b6Mathieu Chartier if (success && owner_ != nullptr && lock_profiling_threshold_ != 0) { 127d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers locking_method_ = owner_->GetCurrentMethod(&locking_dex_pc_); 12800f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } 129d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return success; 1305f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 1315f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1325f79133a435ebcb20000370d56046fe01201dd80Elliott HughesMonitor::~Monitor() { 133d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers CHECK(obj_ != NULL); 134d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers CHECK_EQ(obj_->GetLockWord().GetState(), LockWord::kFatLocked); 1355f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 1365f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 1385f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Links a thread into a monitor's wait set. The monitor lock must be 1395f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * held by the caller of this routine. 1405f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 1415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::AppendToWaitSet(Thread* thread) { 1425f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(owner_ == Thread::Current()); 1435f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(thread != NULL); 144dc33ad5db2dc6ed9b76d5219888626a604debbe1Elliott Hughes DCHECK(thread->wait_next_ == NULL) << thread->wait_next_; 1455f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (wait_set_ == NULL) { 1465f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wait_set_ = thread; 1475f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 1485f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 1495f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1505f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // push_back. 1515f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* t = wait_set_; 1525f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes while (t->wait_next_ != NULL) { 1535f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes t = t->wait_next_; 1545f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 1555f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes t->wait_next_ = thread; 1565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 1575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1585f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 1595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Unlinks a thread from a monitor's wait set. The monitor lock must 1605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * be held by the caller of this routine. 1615f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 1625f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::RemoveFromWaitSet(Thread *thread) { 1635f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(owner_ == Thread::Current()); 1645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(thread != NULL); 1655f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (wait_set_ == NULL) { 1665f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 1675f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 1685f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (wait_set_ == thread) { 1695f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wait_set_ = thread->wait_next_; 1705f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thread->wait_next_ = NULL; 1715f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 1725f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 1735f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1745f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* t = wait_set_; 1755f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes while (t->wait_next_ != NULL) { 1765f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (t->wait_next_ == thread) { 1775f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes t->wait_next_ = thread->wait_next_; 1785f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thread->wait_next_ = NULL; 1795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 1805f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 1815f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes t = t->wait_next_; 1825f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 1835f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 1845f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1856aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartiervoid Monitor::SetObject(mirror::Object* object) { 1866aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier obj_ = object; 1876aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier} 1886aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier 1895f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::Lock(Thread* self) { 190d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(self, monitor_lock_); 191d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers while (true) { 192d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (owner_ == NULL) { // Unowned. 193d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers owner_ = self; 194d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers CHECK_EQ(lock_count_, 0); 195d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // When debugging, save the current monitor holder for future 196d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // acquisition failures to use in sampled logging. 197d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (lock_profiling_threshold_ != 0) { 198d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers locking_method_ = self->GetCurrentMethod(&locking_dex_pc_); 199fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 200d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; 201d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else if (owner_ == self) { // Recursive. 202d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers lock_count_++; 203d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; 204fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 205d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Contended. 206d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers const bool log_contention = (lock_profiling_threshold_ != 0); 207d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint64_t wait_start_ms = log_contention ? 0 : MilliTime(); 208d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers const mirror::ArtMethod* owners_method = locking_method_; 209d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t owners_dex_pc = locking_dex_pc_; 210d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Unlock(self); // Let go of locks in order. 211d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers { 212d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers ScopedThreadStateChange tsc(self, kBlocked); // Change to blocked and give up mutator_lock_. 213d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu2(self, monitor_lock_); // Reacquire monitor_lock_ without mutator_lock_ for Wait. 214d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (owner_ != NULL) { // Did the owner_ give the lock up? 215d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_contenders_.Wait(self); // Still contended so wait. 216d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Woken from contention. 217d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (log_contention) { 218d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint64_t wait_ms = MilliTime() - wait_start_ms; 219d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t sample_percent; 220d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (wait_ms >= lock_profiling_threshold_) { 221d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers sample_percent = 100; 222d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 223d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers sample_percent = 100 * wait_ms / lock_profiling_threshold_; 224d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 225d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (sample_percent != 0 && (static_cast<uint32_t>(rand() % 100) < sample_percent)) { 226d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers const char* owners_filename; 227d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t owners_line_number; 228d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers TranslateLocation(owners_method, owners_dex_pc, &owners_filename, &owners_line_number); 229d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LogContentionEvent(self, wait_ms, sample_percent, owners_filename, owners_line_number); 230d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 231d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 232fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 2335f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 234d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Lock(self); // Reacquire locks in order. 235fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 2365f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 2375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 2386d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogersstatic void ThrowIllegalMonitorStateExceptionF(const char* fmt, ...) 2396d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers __attribute__((format(printf, 1, 2))); 2406d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers 24100f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogersstatic void ThrowIllegalMonitorStateExceptionF(const char* fmt, ...) 242b726dcb581bf72da46527378ccb6889020f0e6e9Ian Rogers SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 2436d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers va_list args; 2446d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers va_start(args, fmt); 24562d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers Thread* self = Thread::Current(); 24662d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers ThrowLocation throw_location = self->GetCurrentLocationForThrow(); 24762d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers self->ThrowNewExceptionV(throw_location, "Ljava/lang/IllegalMonitorStateException;", fmt, args); 248d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (!Runtime::Current()->IsStarted() || VLOG_IS_ON(monitor)) { 24964277f38032208a0c1081ff9e466c04009b96383Brian Carlstrom std::ostringstream ss; 25062d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers self->Dump(ss); 251d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LOG(Runtime::Current()->IsStarted() ? INFO : ERROR) 252d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers << self->GetException(NULL)->Dump() << "\n" << ss.str(); 25364277f38032208a0c1081ff9e466c04009b96383Brian Carlstrom } 2546d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers va_end(args); 2556d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers} 2566d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers 257d423741f91526cada9d081c64ee295ec9863032dElliott Hughesstatic std::string ThreadToString(Thread* thread) { 258d423741f91526cada9d081c64ee295ec9863032dElliott Hughes if (thread == NULL) { 259d423741f91526cada9d081c64ee295ec9863032dElliott Hughes return "NULL"; 260d423741f91526cada9d081c64ee295ec9863032dElliott Hughes } 261d423741f91526cada9d081c64ee295ec9863032dElliott Hughes std::ostringstream oss; 262d423741f91526cada9d081c64ee295ec9863032dElliott Hughes // TODO: alternatively, we could just return the thread's name. 263d423741f91526cada9d081c64ee295ec9863032dElliott Hughes oss << *thread; 264d423741f91526cada9d081c64ee295ec9863032dElliott Hughes return oss.str(); 265d423741f91526cada9d081c64ee295ec9863032dElliott Hughes} 266d423741f91526cada9d081c64ee295ec9863032dElliott Hughes 2672dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersvoid Monitor::FailedUnlock(mirror::Object* o, Thread* expected_owner, Thread* found_owner, 268ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes Monitor* monitor) { 269ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes Thread* current_owner = NULL; 270ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes std::string current_owner_string; 271ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes std::string expected_owner_string; 272ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes std::string found_owner_string; 273ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes { 274ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes // TODO: isn't this too late to prevent threads from disappearing? 275ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes // Acquire thread list lock so threads won't disappear from under us. 27650b35e2fd1a68cd1240e4a9d9f363e11764957d1Ian Rogers MutexLock mu(Thread::Current(), *Locks::thread_list_lock_); 277ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes // Re-read owner now that we hold lock. 278d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers current_owner = (monitor != NULL) ? monitor->GetOwner() : NULL; 279ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes // Get short descriptions of the threads involved. 280ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes current_owner_string = ThreadToString(current_owner); 281ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string = ThreadToString(expected_owner); 282ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes found_owner_string = ThreadToString(found_owner); 283ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes } 2846d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (current_owner == NULL) { 2856d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (found_owner == NULL) { 2866d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of unowned monitor on object of type '%s'" 2876d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " on thread '%s'", 288ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes PrettyTypeOf(o).c_str(), 289ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string.c_str()); 2906d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 2916d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers // Race: the original read found an owner but now there is none 2926d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor owned by '%s' on object of type '%s'" 2936d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " (where now the monitor appears unowned) on thread '%s'", 294ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes found_owner_string.c_str(), 295ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes PrettyTypeOf(o).c_str(), 296ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string.c_str()); 2976d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 2986d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 2996d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (found_owner == NULL) { 3006d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers // Race: originally there was no owner, there is now 3016d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor owned by '%s' on object of type '%s'" 3026d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " (originally believed to be unowned) on thread '%s'", 303ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes current_owner_string.c_str(), 304ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes PrettyTypeOf(o).c_str(), 305ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string.c_str()); 3066d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 3076d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (found_owner != current_owner) { 3086d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers // Race: originally found and current owner have changed 3096d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor originally owned by '%s' (now" 3106d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " owned by '%s') on object of type '%s' on thread '%s'", 311ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes found_owner_string.c_str(), 312ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes current_owner_string.c_str(), 313ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes PrettyTypeOf(o).c_str(), 314ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string.c_str()); 3156d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 3166d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor owned by '%s' on object of type '%s'" 3176d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " on thread '%s", 318ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes current_owner_string.c_str(), 319ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes PrettyTypeOf(o).c_str(), 320ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string.c_str()); 3216d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 3226d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 3236d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 3245f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 3255f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 326d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogersbool Monitor::Unlock(Thread* self) { 3275f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 328d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(self, monitor_lock_); 3296d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers Thread* owner = owner_; 3306d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (owner == self) { 3315f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // We own the monitor, so nobody else can be in here. 3325f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (lock_count_ == 0) { 3335f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes owner_ = NULL; 33433dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_method_ = NULL; 3350399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers locking_dex_pc_ = 0; 336d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Wake a contender. 337d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_contenders_.Signal(self); 3385f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 3395f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes --lock_count_; 3405f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 3415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 3425f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // We don't own this, so we're not allowed to unlock it. 3435f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // The JNI spec says that we should throw IllegalMonitorStateException 3445f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // in this case. 3456d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers FailedUnlock(obj_, self, owner, this); 3465f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return false; 3475f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 3485f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return true; 3495f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 3505f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 3515f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 3525f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Wait on a monitor until timeout, interrupt, or notification. Used for 3535f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Object.wait() and (somewhat indirectly) Thread.sleep() and Thread.join(). 3545f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 3555f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * If another thread calls Thread.interrupt(), we throw InterruptedException 3565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * and return immediately if one of the following are true: 3575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - blocked in wait(), wait(long), or wait(long, int) methods of Object 3585f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - blocked in join(), join(long), or join(long, int) methods of Thread 3595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - blocked in sleep(long), or sleep(long, int) methods of Thread 3605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Otherwise, we set the "interrupted" flag. 3615f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 3625f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Checks to make sure that "ns" is in the range 0-999999 3635f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * (i.e. fractions of a millisecond) and throws the appropriate 3645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * exception if it isn't. 3655f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 3665f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The spec allows "spurious wakeups", and recommends that all code using 3675f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Object.wait() do so in a loop. This appears to derive from concerns 3685f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * about pthread_cond_wait() on multiprocessor systems. Some commentary 3695f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * on the web casts doubt on whether these can/should occur. 3705f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 3715f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Since we're allowed to wake up "early", we clamp extremely long durations 3725f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * to return at the end of the 32-bit time epoch. 3735f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 3744cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughesvoid Monitor::Wait(Thread* self, int64_t ms, int32_t ns, 3754cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes bool interruptShouldThrow, ThreadState why) { 3765f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 3774cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes DCHECK(why == kTimedWaiting || why == kWaiting || why == kSleeping); 3785f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 379d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Lock(self); 380d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers 3815f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Make sure that we hold the lock. 3825f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (owner_ != self) { 3836d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before wait()"); 384d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Unlock(self); 3855f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 3865f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 3874cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes 388df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes // We need to turn a zero-length timed wait into a regular wait because 389df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes // Object.wait(0, 0) is defined as Object.wait(0), which is defined as Object.wait(). 390df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes if (why == kTimedWaiting && (ms == 0 && ns == 0)) { 391df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes why = kWaiting; 392df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes } 393df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes 3945f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Enforce the timeout range. 3955f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (ms < 0 || ns < 0 || ns > 999999) { 39662d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers ThrowLocation throw_location = self->GetCurrentLocationForThrow(); 39762d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers self->ThrowNewExceptionF(throw_location, "Ljava/lang/IllegalArgumentException;", 39862d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers "timeout arguments out of range: ms=%lld ns=%d", ms, ns); 399d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Unlock(self); 4005f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 4015f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 4025f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4035f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 4045f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Add ourselves to the set of threads waiting on this monitor, and 4055f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * release our hold. We need to let it go even if we're a few levels 4065f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * deep in a recursive lock, and we need to restore that later. 4075f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 4085f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * We append to the wait set ahead of clearing the count and owner 4095f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * fields so the subroutine can check that the calling thread owns 4105f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * the monitor. Aside from that, the order of member updates is 4115f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * not order sensitive as we hold the pthread mutex. 4125f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 4135f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes AppendToWaitSet(self); 4140399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers int prev_lock_count = lock_count_; 4155f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes lock_count_ = 0; 4165f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes owner_ = NULL; 417ea46f950e7a51585db293cd7f047de190a482414Brian Carlstrom const mirror::ArtMethod* saved_method = locking_method_; 41833dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_method_ = NULL; 4190399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers uintptr_t saved_dex_pc = locking_dex_pc_; 4200399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers locking_dex_pc_ = 0; 4215f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4225f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 4234cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes * Update thread state. If the GC wakes up, it'll ignore us, knowing 4245f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * that we won't touch any references in this state, and we'll check 4255f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * our suspend mode before we transition out. 4265f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 4274cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes self->TransitionFromRunnableToSuspended(why); 4285f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 429b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes bool was_interrupted = false; 43000f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers { 43100f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Pseudo-atomically wait on self's wait_cond_ and release the monitor lock. 43250b35e2fd1a68cd1240e4a9d9f363e11764957d1Ian Rogers MutexLock mu(self, *self->wait_mutex_); 4335f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 43400f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Set wait_monitor_ to the monitor object we will be waiting on. When wait_monitor_ is 43500f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // non-NULL a notifying or interrupting thread must signal the thread's wait_cond_ to wake it 43600f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // up. 43700f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers DCHECK(self->wait_monitor_ == NULL); 43800f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers self->wait_monitor_ = this; 4395f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 44000f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Release the monitor lock. 441d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_contenders_.Signal(self); 442d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Unlock(self); 44300f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers 444b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes // Handle the case where the thread was interrupted before we called wait(). 44500f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers if (self->interrupted_) { 446b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes was_interrupted = true; 44700f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } else { 44800f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Wait for a notification or a timeout to occur. 4494cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes if (why == kWaiting) { 450c604d731730b43231f63040c8db1d58304da0cf3Ian Rogers self->wait_cond_->Wait(self); 45100f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } else { 4524cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes DCHECK(why == kTimedWaiting || why == kSleeping) << why; 453c604d731730b43231f63040c8db1d58304da0cf3Ian Rogers self->wait_cond_->TimedWait(self, ms, ns); 45400f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } 45500f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers if (self->interrupted_) { 456b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes was_interrupted = true; 45700f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } 45800f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers self->interrupted_ = false; 45900f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } 4605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 4615f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 46200f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Set self->status back to kRunnable, and self-suspend if needed. 46300f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers self->TransitionFromSuspendedToRunnable(); 4645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 465b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes { 466b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes // We reset the thread's wait_monitor_ field after transitioning back to runnable so 467b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes // that a thread in a waiting/sleeping state has a non-null wait_monitor_ for debugging 468b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes // and diagnostic purposes. (If you reset this earlier, stack dumps will claim that threads 469b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes // are waiting on "null".) 470b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes MutexLock mu(self, *self->wait_mutex_); 471b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes DCHECK(self->wait_monitor_ != NULL); 472b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes self->wait_monitor_ = NULL; 473b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes } 474b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes 475d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Re-acquire the monitor and lock. 47600f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers Lock(self); 477d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Lock(self); 47881d425b0b232962441616f8b14f73620bffef5e5Ian Rogers self->wait_mutex_->AssertNotHeld(self); 4795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4805f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 4815f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * We remove our thread from wait set after restoring the count 4825f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * and owner fields so the subroutine can check that the calling 4835f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * thread owns the monitor. Aside from that, the order of member 4845f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * updates is not order sensitive as we hold the pthread mutex. 4855f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 4865f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes owner_ = self; 4870399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers lock_count_ = prev_lock_count; 4880399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers locking_method_ = saved_method; 4890399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers locking_dex_pc_ = saved_dex_pc; 4905f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes RemoveFromWaitSet(self); 4915f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 492b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes if (was_interrupted) { 4935f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 4945f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * We were interrupted while waiting, or somebody interrupted an 4955f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * un-interruptible thread earlier and we're bailing out immediately. 4965f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 4975f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The doc sayeth: "The interrupted status of the current thread is 4985f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * cleared when this exception is thrown." 4995f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 50000f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers { 50150b35e2fd1a68cd1240e4a9d9f363e11764957d1Ian Rogers MutexLock mu(self, *self->wait_mutex_); 50200f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers self->interrupted_ = false; 50300f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } 5045f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (interruptShouldThrow) { 50562d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers ThrowLocation throw_location = self->GetCurrentLocationForThrow(); 50662d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers self->ThrowNewException(throw_location, "Ljava/lang/InterruptedException;", NULL); 5075f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5085f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 509d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Unlock(self); 5105f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 5115f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5125f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::Notify(Thread* self) { 5135f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 514d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(self, monitor_lock_); 5155f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Make sure that we hold the lock. 5165f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (owner_ != self) { 5176d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notify()"); 5185f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 5195f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5205f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Signal the first waiting thread in the wait set. 5215f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes while (wait_set_ != NULL) { 5225f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* thread = wait_set_; 5235f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wait_set_ = thread->wait_next_; 5245f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thread->wait_next_ = NULL; 5255f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5265f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Check to see if the thread is still waiting. 52750b35e2fd1a68cd1240e4a9d9f363e11764957d1Ian Rogers MutexLock mu(self, *thread->wait_mutex_); 5285f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (thread->wait_monitor_ != NULL) { 529c604d731730b43231f63040c8db1d58304da0cf3Ian Rogers thread->wait_cond_->Signal(self); 5305f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 5315f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5325f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5335f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 5345f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5355f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::NotifyAll(Thread* self) { 5365f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 537d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(self, monitor_lock_); 5385f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Make sure that we hold the lock. 5395f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (owner_ != self) { 5406d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notifyAll()"); 5415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 5425f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5435f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Signal all threads in the wait set. 5445f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes while (wait_set_ != NULL) { 5455f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* thread = wait_set_; 5465f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wait_set_ = thread->wait_next_; 5475f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thread->wait_next_ = NULL; 5485f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thread->Notify(); 5495f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5505f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 5515f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5525f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 553d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * Changes the shape of a monitor from thin to fat, preserving the internal lock state. The calling 554d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * thread must own the lock or the owner must be suspended. There's a race with other threads 555d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * inflating the lock and so the caller should read the monitor following the call. 5565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 557ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartiervoid Monitor::Inflate(Thread* self, Thread* owner, mirror::Object* obj, int32_t hash_code) { 5585f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 5595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(obj != NULL); 5605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Allocate and acquire a new monitor. 561ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier UniquePtr<Monitor> m(new Monitor(owner, obj, hash_code)); 562d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (m->Install(self)) { 563d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers VLOG(monitor) << "monitor: thread " << owner->GetThreadId() 564d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers << " created monitor " << m.get() << " for object " << obj; 565d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Runtime::Current()->GetMonitorList()->Add(m.release()); 566ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier CHECK_EQ(obj->GetLockWord().GetState(), LockWord::kFatLocked); 567ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 568ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier} 569ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier 570ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartiervoid Monitor::InflateThinLocked(Thread* self, mirror::Object* obj, LockWord lock_word, 571ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier uint32_t hash_code) { 572ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier DCHECK_EQ(lock_word.GetState(), LockWord::kThinLocked); 573ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier uint32_t owner_thread_id = lock_word.ThinLockOwner(); 574ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier if (owner_thread_id == self->GetThreadId()) { 575ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // We own the monitor, we can easily inflate it. 576ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier Inflate(self, self, obj, hash_code); 577ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } else { 578ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier ThreadList* thread_list = Runtime::Current()->GetThreadList(); 579ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Suspend the owner, inflate. First change to blocked and give up mutator_lock_. 580ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier ScopedThreadStateChange tsc(self, kBlocked); 581ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier if (lock_word == obj->GetLockWord()) { // If lock word hasn't changed. 582ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier bool timed_out; 583ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier Thread* owner = thread_list->SuspendThreadByThreadId(lock_word.ThinLockOwner(), false, 584ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier &timed_out); 585ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier if (owner != nullptr) { 586ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // We succeeded in suspending the thread, check the lock's status didn't change. 587ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier lock_word = obj->GetLockWord(); 588ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier if (lock_word.GetState() == LockWord::kThinLocked && 589ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier lock_word.ThinLockOwner() == owner_thread_id) { 590ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Go ahead and inflate the lock. 591ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier Inflate(self, owner, obj, hash_code); 592ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 593ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier thread_list->Resume(owner, false); 594ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 595ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 596d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 5975f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 5985f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5992dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersvoid Monitor::MonitorEnter(Thread* self, mirror::Object* obj) { 6004681c809ba35d50fab92c592ce8d2c7f8b2731f7Elliott Hughes DCHECK(self != NULL); 6014681c809ba35d50fab92c592ce8d2c7f8b2731f7Elliott Hughes DCHECK(obj != NULL); 602d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t thread_id = self->GetThreadId(); 603d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers size_t contention_count = 0; 604d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers while (true) { 605d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LockWord lock_word = obj->GetLockWord(); 606d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 607d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: { 608d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LockWord thin_locked(LockWord::FromThinLockId(thread_id, 0)); 609d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (obj->CasLockWord(lock_word, thin_locked)) { 610d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Success! 611d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 612d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers continue; // Go again. 6135f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 614d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: { 615d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t owner_thread_id = lock_word.ThinLockOwner(); 616d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (owner_thread_id == thread_id) { 617d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // We own the lock, increase the recursion count. 618d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t new_count = lock_word.ThinLockCount() + 1; 619d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (LIKELY(new_count <= LockWord::kThinLockMaxCount)) { 620d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LockWord thin_locked(LockWord::FromThinLockId(thread_id, new_count)); 621d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers obj->SetLockWord(thin_locked); 622d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Success! 623d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 624d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // We'd overflow the recursion count, so inflate the monitor. 625ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier InflateThinLocked(self, obj, lock_word, mirror::Object::GenerateIdentityHashCode()); 626d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 627d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 628d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Contention. 629d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers contention_count++; 630ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier Runtime* runtime = Runtime::Current(); 631ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier if (contention_count <= runtime->GetMaxSpinsBeforeThinkLockInflation()) { 632d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers NanoSleep(1000); // Sleep for 1us and re-attempt. 6335f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 634d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers contention_count = 0; 635ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier InflateThinLocked(self, obj, lock_word, mirror::Object::GenerateIdentityHashCode()); 6365f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 638d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers continue; // Start from the beginning. 639d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 640d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 641d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 642d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers mon->Lock(self); 643d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Success! 6445f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 645ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: { 646ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Inflate with the existing hashcode. 647ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier Inflate(self, nullptr, obj, lock_word.GetHashCode()); 648ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier break; 649ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 6505f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6515f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6525f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 6535f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 6542dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersbool Monitor::MonitorExit(Thread* self, mirror::Object* obj) { 6555f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 6565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(obj != NULL); 6575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 658d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LockWord lock_word = obj->GetLockWord(); 659d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 660ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: 661ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Fall-through. 662d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: 663d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers FailedUnlock(obj, self, NULL, NULL); 664d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return false; // Failure. 665d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: { 666d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t thread_id = self->GetThreadId(); 667d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t owner_thread_id = lock_word.ThinLockOwner(); 668d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (owner_thread_id != thread_id) { 669d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // TODO: there's a race here with the owner dying while we unlock. 670d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Thread* owner = 671d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Runtime::Current()->GetThreadList()->FindThreadByThreadId(lock_word.ThinLockOwner()); 672d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers FailedUnlock(obj, self, owner, NULL); 673d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return false; // Failure. 6745f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 675d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // We own the lock, decrease the recursion count. 676d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (lock_word.ThinLockCount() != 0) { 677d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t new_count = lock_word.ThinLockCount() - 1; 678d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LockWord thin_locked(LockWord::FromThinLockId(thread_id, new_count)); 679d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers obj->SetLockWord(thin_locked); 680d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 681d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers obj->SetLockWord(LockWord()); 682d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 683d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return true; // Success! 6845f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6855f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 686d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 687d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 688d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return mon->Unlock(self); 6895f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 690d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers default: 691d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LOG(FATAL) << "Unreachable"; 692d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return false; 6935f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6945f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 6955f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 6965f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 6975f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Object.wait(). Also called for class init. 6985f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 6992dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersvoid Monitor::Wait(Thread* self, mirror::Object *obj, int64_t ms, int32_t ns, 7004cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes bool interruptShouldThrow, ThreadState why) { 701d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers DCHECK(self != NULL); 702d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers DCHECK(obj != NULL); 7035f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 704d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LockWord lock_word = obj->GetLockWord(); 705d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 706ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: 707ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Fall-through. 708d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: 7096d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before wait()"); 710d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Failure. 711d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: { 712d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t thread_id = self->GetThreadId(); 713d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t owner_thread_id = lock_word.ThinLockOwner(); 714d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (owner_thread_id != thread_id) { 715d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before wait()"); 716d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Failure. 717d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 718d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // We own the lock, inflate to enqueue ourself on the Monitor. 719ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier Inflate(self, self, obj, mirror::Object::GenerateIdentityHashCode()); 720d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers lock_word = obj->GetLockWord(); 721d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 722d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers break; 7235f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 724d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: 725d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers break; // Already set for a wait. 7265f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 727d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 728d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers mon->Wait(self, ms, ns, interruptShouldThrow, why); 7295f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 7305f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 73113c479e7e9b62115fe0409e5273c1e976a1c09f9Ian Rogersvoid Monitor::DoNotify(Thread* self, mirror::Object* obj, bool notify_all) { 732d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers DCHECK(self != NULL); 733d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers DCHECK(obj != NULL); 7345f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 735d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LockWord lock_word = obj->GetLockWord(); 736d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 737ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: 738ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Fall-through. 739d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: 7406d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notify()"); 741d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Failure. 742d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: { 743d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t thread_id = self->GetThreadId(); 744d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t owner_thread_id = lock_word.ThinLockOwner(); 745d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (owner_thread_id != thread_id) { 746d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notify()"); 747d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Failure. 748d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 749d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // We own the lock but there's no Monitor and therefore no waiters. 750d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Success. 751d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 752d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 753d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 754d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 755d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (notify_all) { 756d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers mon->NotifyAll(self); 757d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 758d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers mon->Notify(self); 759d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 760d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Success. 7615f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7625f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7635f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 7645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 765d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogersuint32_t Monitor::GetLockOwnerThreadId(mirror::Object* obj) { 766d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers DCHECK(obj != NULL); 7675f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 768d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LockWord lock_word = obj->GetLockWord(); 769d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 770ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: 771ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Fall-through. 772d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: 773d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return ThreadList::kInvalidThreadId; 774d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: 775d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return lock_word.ThinLockOwner(); 776d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 777d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 778d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return mon->GetOwnerThreadId(); 7795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 780d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers default: 781d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LOG(FATAL) << "Unreachable"; 782d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return ThreadList::kInvalidThreadId; 7835f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7845f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 7855f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 7868e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughesvoid Monitor::DescribeWait(std::ostream& os, const Thread* thread) { 787f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes ThreadState state = thread->GetState(); 7888e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes 789d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers int32_t object_identity_hashcode = 0; 790d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t lock_owner = ThreadList::kInvalidThreadId; 791d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers std::string pretty_type; 792b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes if (state == kWaiting || state == kTimedWaiting || state == kSleeping) { 793b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes if (state == kSleeping) { 794b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes os << " - sleeping on "; 795b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes } else { 796b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes os << " - waiting on "; 797b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes } 79800f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers { 799f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes Thread* self = Thread::Current(); 800f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes MutexLock mu(self, *thread->wait_mutex_); 801b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes Monitor* monitor = thread->wait_monitor_; 802b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes if (monitor != NULL) { 803d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers mirror::Object* object = monitor->obj_; 804d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers object_identity_hashcode = object->IdentityHashCode(); 805d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers pretty_type = PrettyTypeOf(object); 806b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes } 8078e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 80834e069606d6f1698cd3c33b39e72b79ae27e1c7bElliott Hughes } else if (state == kBlocked) { 8098e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes os << " - waiting to lock "; 810d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers mirror::Object* object = thread->monitor_enter_object_; 8118e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes if (object != NULL) { 812d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers object_identity_hashcode = object->IdentityHashCode(); 813d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers lock_owner = object->GetLockOwnerThreadId(); 814d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers pretty_type = PrettyTypeOf(object); 8158e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 8168e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } else { 8178e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes // We're not waiting on anything. 8188e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes return; 8198e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 8208e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes 8218e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes // - waiting on <0x6008c468> (a java.lang.Class<java.lang.ref.ReferenceQueue>) 822d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers os << StringPrintf("<0x%08x> (a %s)", object_identity_hashcode, pretty_type.c_str()); 8238e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes 824c5dc2ff2d1beb3ff84f93d2c7ebe07c46b76956aElliott Hughes // - waiting to lock <0x613f83d8> (a java.lang.Object) held by thread 5 825d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (lock_owner != ThreadList::kInvalidThreadId) { 8268e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes os << " held by thread " << lock_owner; 8278e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 8288e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes 8298e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes os << "\n"; 8308e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes} 8318e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes 8322dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersmirror::Object* Monitor::GetContendedMonitor(Thread* thread) { 833f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes // This is used to implement JDWP's ThreadReference.CurrentContendedMonitor, and has a bizarre 834f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes // definition of contended that includes a monitor a thread is trying to enter... 8352dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogers mirror::Object* result = thread->monitor_enter_object_; 836d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (result == NULL) { 837d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // ...but also a monitor that the thread is waiting on. 838f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes MutexLock mu(Thread::Current(), *thread->wait_mutex_); 839f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes Monitor* monitor = thread->wait_monitor_; 840f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes if (monitor != NULL) { 841d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers result = monitor->GetObject(); 842f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes } 843f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes } 844d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return result; 845f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes} 846f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes 8472dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersvoid Monitor::VisitLocks(StackVisitor* stack_visitor, void (*callback)(mirror::Object*, void*), 8482dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogers void* callback_context) { 849ea46f950e7a51585db293cd7f047de190a482414Brian Carlstrom mirror::ArtMethod* m = stack_visitor->GetMethod(); 85008fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes CHECK(m != NULL); 85108fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 85208fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes // Native methods are an easy special case. 85308fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes // TODO: use the JNI implementation's table of explicit MonitorEnter calls and dump those too. 85408fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes if (m->IsNative()) { 85508fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes if (m->IsSynchronized()) { 8562dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogers mirror::Object* jni_this = stack_visitor->GetCurrentSirt()->GetReference(0); 8574993bbc8eda377804e585efd918f8ab9d9eab7d4Elliott Hughes callback(jni_this, callback_context); 85808fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 85908fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes return; 86008fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 86108fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 86261f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao // Proxy methods should not be synchronized. 86361f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao if (m->IsProxyMethod()) { 86461f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao CHECK(!m->IsSynchronized()); 86561f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao return; 86661f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao } 86761f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao 86808fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes // <clinit> is another special case. The runtime holds the class lock while calling <clinit>. 86908fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes MethodHelper mh(m); 87008fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes if (mh.IsClassInitializer()) { 8714993bbc8eda377804e585efd918f8ab9d9eab7d4Elliott Hughes callback(m->GetDeclaringClass(), callback_context); 87208fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes // Fall through because there might be synchronization in the user code too. 87308fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 87408fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 87508fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes // Is there any reason to believe there's any synchronization in this method? 87608fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes const DexFile::CodeItem* code_item = mh.GetCodeItem(); 877caf7654a0e6c76c7489970b1a246fccf220f9982Elliott Hughes CHECK(code_item != NULL) << PrettyMethod(m); 87808fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes if (code_item->tries_size_ == 0) { 8797934ac288acfb2552bb0b06ec1f61e5820d924a4Brian Carlstrom return; // No "tries" implies no synchronization, so no held locks to report. 88008fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 88108fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 88280537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes // Ask the verifier for the dex pcs of all the monitor-enter instructions corresponding to 88380537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes // the locks held in this stack frame. 88480537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes std::vector<uint32_t> monitor_enter_dex_pcs; 88580537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes verifier::MethodVerifier::FindLocksAtDexPc(m, stack_visitor->GetDexPc(), monitor_enter_dex_pcs); 88680537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes if (monitor_enter_dex_pcs.empty()) { 88780537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes return; 88880537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes } 88908fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 89080537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes for (size_t i = 0; i < monitor_enter_dex_pcs.size(); ++i) { 89180537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes // The verifier works in terms of the dex pcs of the monitor-enter instructions. 89280537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes // We want the registers used by those instructions (so we can read the values out of them). 89380537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes uint32_t dex_pc = monitor_enter_dex_pcs[i]; 89480537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes uint16_t monitor_enter_instruction = code_item->insns_[dex_pc]; 89508fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 89680537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes // Quick sanity check. 89780537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes if ((monitor_enter_instruction & 0xff) != Instruction::MONITOR_ENTER) { 89880537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes LOG(FATAL) << "expected monitor-enter @" << dex_pc << "; was " 89980537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes << reinterpret_cast<void*>(monitor_enter_instruction); 90008fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 90180537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes 90280537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes uint16_t monitor_register = ((monitor_enter_instruction >> 8) & 0xff); 9032dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogers mirror::Object* o = reinterpret_cast<mirror::Object*>(stack_visitor->GetVReg(m, monitor_register, 9042dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogers kReferenceVReg)); 9054993bbc8eda377804e585efd918f8ab9d9eab7d4Elliott Hughes callback(o, callback_context); 90608fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 90708fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes} 90808fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 909d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogersbool Monitor::IsValidLockWord(LockWord lock_word) { 910d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 911d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: 912d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Nothing to check. 913d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return true; 914d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: 915d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Basic sanity check of owner. 916d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return lock_word.ThinLockOwner() != ThreadList::kInvalidThreadId; 917d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 918d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Check the monitor appears in the monitor list. 919d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 920d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MonitorList* list = Runtime::Current()->GetMonitorList(); 921d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(Thread::Current(), list->monitor_list_lock_); 922d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers for (Monitor* list_mon : list->list_) { 923d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (mon == list_mon) { 924d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return true; // Found our monitor. 925d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 9267dfb28c066159e6cde8181720f0c451a700ef966Ian Rogers } 927d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return false; // Fail - unowned monitor in an object. 9287dfb28c066159e6cde8181720f0c451a700ef966Ian Rogers } 929ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: 930ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier return true; 931d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers default: 932d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LOG(FATAL) << "Unreachable"; 933d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return false; 9347dfb28c066159e6cde8181720f0c451a700ef966Ian Rogers } 9357dfb28c066159e6cde8181720f0c451a700ef966Ian Rogers} 9367dfb28c066159e6cde8181720f0c451a700ef966Ian Rogers 937ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartierbool Monitor::IsLocked() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 938ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier MutexLock mu(Thread::Current(), monitor_lock_); 939ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier return owner_ != nullptr; 940ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier} 941ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier 942ea46f950e7a51585db293cd7f047de190a482414Brian Carlstromvoid Monitor::TranslateLocation(const mirror::ArtMethod* method, uint32_t dex_pc, 943d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers const char** source_file, uint32_t* line_number) const { 94433dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao // If method is null, location is unknown 94533dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao if (method == NULL) { 946d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers *source_file = ""; 947d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers *line_number = 0; 94833dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao return; 94933dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao } 9506d4d9fcb4f01e287ee29e81cd1c941ee5d11d379Ian Rogers MethodHelper mh(method); 951d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers *source_file = mh.GetDeclaringClassSourceFile(); 952d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (*source_file == NULL) { 953d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers *source_file = ""; 954d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 955d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers *line_number = mh.GetLineNumFromDexPC(dex_pc); 956d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers} 957d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers 958d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogersuint32_t Monitor::GetOwnerThreadId() { 959d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(Thread::Current(), monitor_lock_); 960d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Thread* owner = owner_; 961d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (owner != NULL) { 962d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return owner->GetThreadId(); 963d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 964d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return ThreadList::kInvalidThreadId; 96512c51e3e5a8b5655351539618f1cf2331f52d1abElliott Hughes } 96633dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao} 96733dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao 968c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu ChartierMonitorList::MonitorList() 969c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier : allow_new_monitors_(true), monitor_list_lock_("MonitorList lock"), 970c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier monitor_add_condition_("MonitorList disallow condition", monitor_list_lock_) { 971c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 972c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 973c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott HughesMonitorList::~MonitorList() { 97450b35e2fd1a68cd1240e4a9d9f363e11764957d1Ian Rogers MutexLock mu(Thread::Current(), monitor_list_lock_); 975c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes STLDeleteElements(&list_); 976c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 977c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 978c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartiervoid MonitorList::DisallowNewMonitors() { 97950b35e2fd1a68cd1240e4a9d9f363e11764957d1Ian Rogers MutexLock mu(Thread::Current(), monitor_list_lock_); 980c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier allow_new_monitors_ = false; 981c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier} 982c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier 983c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartiervoid MonitorList::AllowNewMonitors() { 984c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier Thread* self = Thread::Current(); 985c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier MutexLock mu(self, monitor_list_lock_); 986c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier allow_new_monitors_ = true; 987c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier monitor_add_condition_.Broadcast(self); 988c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier} 989c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier 990c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartiervoid MonitorList::Add(Monitor* m) { 991c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier Thread* self = Thread::Current(); 992c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier MutexLock mu(self, monitor_list_lock_); 993c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier while (UNLIKELY(!allow_new_monitors_)) { 994c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier monitor_add_condition_.WaitHoldingLocks(self); 995c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier } 996c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes list_.push_front(m); 997c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 998c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 9996aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartiervoid MonitorList::SweepMonitorList(RootVisitor visitor, void* arg) { 100050b35e2fd1a68cd1240e4a9d9f363e11764957d1Ian Rogers MutexLock mu(Thread::Current(), monitor_list_lock_); 100102e25119b15a6f619f17db99f5d05124a5807ff3Mathieu Chartier for (auto it = list_.begin(); it != list_.end(); ) { 1002c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes Monitor* m = *it; 10036aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier mirror::Object* obj = m->GetObject(); 10046aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier mirror::Object* new_obj = visitor(obj, arg); 10056aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier if (new_obj == nullptr) { 10066aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier VLOG(monitor) << "freeing monitor " << m << " belonging to unmarked object " 10076aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier << m->GetObject(); 1008c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes delete m; 1009c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes it = list_.erase(it); 1010c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes } else { 10116aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier m->SetObject(new_obj); 1012c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes ++it; 1013c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes } 1014c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes } 1015c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 1016c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 1017d9c4fc94fa618617f94e1de9af5f034549100753Ian RogersMonitorInfo::MonitorInfo(mirror::Object* obj) : owner_(NULL), entry_count_(0) { 1018d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers DCHECK(obj != NULL); 1019d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers 1020d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LockWord lock_word = obj->GetLockWord(); 1021d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 1022d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: 1023ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Fall-through. 1024ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: 1025d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers break; 1026d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: 1027d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers owner_ = Runtime::Current()->GetThreadList()->FindThreadByThreadId(lock_word.ThinLockOwner()); 1028d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers entry_count_ = 1 + lock_word.ThinLockCount(); 1029d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Thin locks have no waiters. 1030d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers break; 1031d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 1032d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 1033d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers owner_ = mon->owner_; 1034d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers entry_count_ = 1 + mon->lock_count_; 1035d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers for (Thread* waiter = mon->wait_set_; waiter != NULL; waiter = waiter->wait_next_) { 1036d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers waiters_.push_back(waiter); 1037d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 1038d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers break; 1039f327e07b37e349b1ec5eaad6dc294a9b7a081d20Elliott Hughes } 1040f327e07b37e349b1ec5eaad6dc294a9b7a081d20Elliott Hughes } 1041f327e07b37e349b1ec5eaad6dc294a9b7a081d20Elliott Hughes} 1042f327e07b37e349b1ec5eaad6dc294a9b7a081d20Elliott Hughes 10435f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} // namespace art 1044