monitor.cc revision 14691c5e786e8c2c5734f687e4c96217340771be
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 19f0dc8b5519102b3d3e738aed846975ae4239421eMathieu Chartier#define ATRACE_TAG ATRACE_TAG_DALVIK 20f0dc8b5519102b3d3e738aed846975ae4239421eMathieu Chartier 21f0dc8b5519102b3d3e738aed846975ae4239421eMathieu Chartier#include <cutils/trace.h> 2208fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes#include <vector> 2308fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 2476b6167407c2b6f5d40ad895b2793a6b037f54b2Elliott Hughes#include "base/mutex.h" 251aa246dec5abe212f699de1413a0c4a191ca364aElliott Hughes#include "base/stl_util.h" 2633dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao#include "class_linker.h" 274f6ad8ab428038129b2d0d6c40b7fd625cca15e1Ian Rogers#include "dex_file-inl.h" 2808fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes#include "dex_instruction.h" 29d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers#include "lock_word-inl.h" 30ea46f950e7a51585db293cd7f047de190a482414Brian Carlstrom#include "mirror/art_method-inl.h" 314f6ad8ab428038129b2d0d6c40b7fd625cca15e1Ian Rogers#include "mirror/class-inl.h" 3205f3057d6a4d23d712092ccd36a531590bff323bIan Rogers#include "mirror/object-inl.h" 332dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogers#include "mirror/object_array-inl.h" 3400f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers#include "scoped_thread_state_change.h" 355f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#include "thread.h" 368e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes#include "thread_list.h" 3708fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes#include "verifier/method_verifier.h" 38044288fb8f69e154862763a6b3bfea2bac1b397eElliott Hughes#include "well_known_classes.h" 395f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 405f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesnamespace art { 415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 42b9001abff3a45f1ae90536da7dd1ec28a6ae0174Mathieu Chartierstatic constexpr uint64_t kLongWaitMs = 100; 43b9001abff3a45f1ae90536da7dd1ec28a6ae0174Mathieu Chartier 445f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 45d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * Every Object has a monitor associated with it, but not every Object is actually locked. Even 46d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * the ones that are locked do not need a full-fledged monitor until a) there is actual contention 47d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * or b) wait() is called on the Object. 485f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 49d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * For Android, we have implemented a scheme similar to the one described in Bacon et al.'s 50d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * "Thin locks: featherweight synchronization for Java" (ACM 1998). Things are even easier for us, 51d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * though, because we have a full 32 bits to work with. 525f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 53d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * The two states of an Object's lock are referred to as "thin" and "fat". A lock may transition 54d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * from the "thin" state to the "fat" state and this transition is referred to as inflation. Once 55d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * a lock has been inflated it remains in the "fat" state indefinitely. 565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 57d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * The lock value itself is stored in mirror::Object::monitor_ and the representation is described 58d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * in the LockWord value type. 5954e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes * 605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Monitors provide: 615f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - mutually exclusive access to resources 625f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - a way for multiple threads to wait for notification 635f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * In effect, they fill the role of both mutexes and condition variables. 655f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 66d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * Only one thread can own the monitor at any time. There may be several threads waiting on it 67d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * (the wait call unlocks it). One or more waiting threads may be getting interrupted or notified 68d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers * at any given time. 695f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 7054e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes 71fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughesbool (*Monitor::is_sensitive_thread_hook_)() = NULL; 72fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughesuint32_t Monitor::lock_profiling_threshold_ = 0; 7332d6e1e5654433d7eadede89e1c770b2c839aee9Elliott Hughes 74fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughesbool Monitor::IsSensitiveThread() { 75fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes if (is_sensitive_thread_hook_ != NULL) { 76fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes return (*is_sensitive_thread_hook_)(); 77fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 78fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes return false; 79fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes} 80fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes 814dd9b4d95eec9db5338fb9bf132f9bb8facf6cf4Elliott Hughesvoid Monitor::Init(uint32_t lock_profiling_threshold, bool (*is_sensitive_thread_hook)()) { 82fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes lock_profiling_threshold_ = lock_profiling_threshold; 83fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes is_sensitive_thread_hook_ = is_sensitive_thread_hook; 8432d6e1e5654433d7eadede89e1c770b2c839aee9Elliott Hughes} 8532d6e1e5654433d7eadede89e1c770b2c839aee9Elliott Hughes 86ef7d42fca18c16fbaf103822ad16f23246e2905dIan RogersMonitor::Monitor(Thread* self, Thread* owner, mirror::Object* obj, int32_t hash_code) 8700f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers : monitor_lock_("a monitor lock", kMonitorLock), 88d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_contenders_("monitor contenders", monitor_lock_), 8946bc778f1feed02b20d25e3d03470c93ca2c0506Mathieu Chartier num_waiters_(0), 9000f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers owner_(owner), 915f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes lock_count_(0), 9294f7b49578b6aaa80de8ffed230648d601393905Hiroshi Yamauchi obj_(GcRoot<mirror::Object>(obj)), 935f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wait_set_(NULL), 94ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier hash_code_(hash_code), 9533dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_method_(NULL), 96ef7d42fca18c16fbaf103822ad16f23246e2905dIan Rogers locking_dex_pc_(0), 9774240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe monitor_id_(MonitorPool::ComputeMonitorId(this, self)) { 9874240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe#ifdef __LP64__ 9974240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe DCHECK(false) << "Should not be reached in 64b"; 10074240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe next_free_ = nullptr; 10174240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe#endif 10274240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe // We should only inflate a lock if the owner is ourselves or suspended. This avoids a race 10374240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe // with the owner unlocking the thin-lock. 10474240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe CHECK(owner == nullptr || owner == self || owner->IsSuspended()); 10574240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe // The identity hash code is set for the life time of the monitor. 10674240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe} 10774240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe 10874240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas GampeMonitor::Monitor(Thread* self, Thread* owner, mirror::Object* obj, int32_t hash_code, 10974240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe MonitorId id) 11074240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe : monitor_lock_("a monitor lock", kMonitorLock), 11174240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe monitor_contenders_("monitor contenders", monitor_lock_), 11274240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe num_waiters_(0), 11374240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe owner_(owner), 11474240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe lock_count_(0), 11594f7b49578b6aaa80de8ffed230648d601393905Hiroshi Yamauchi obj_(GcRoot<mirror::Object>(obj)), 11674240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe wait_set_(NULL), 11774240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe hash_code_(hash_code), 11874240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe locking_method_(NULL), 11974240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe locking_dex_pc_(0), 12074240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe monitor_id_(id) { 12174240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe#ifdef __LP64__ 12274240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe next_free_ = nullptr; 12374240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe#endif 124d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // We should only inflate a lock if the owner is ourselves or suspended. This avoids a race 125d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // with the owner unlocking the thin-lock. 126ef7d42fca18c16fbaf103822ad16f23246e2905dIan Rogers CHECK(owner == nullptr || owner == self || owner->IsSuspended()); 127ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // The identity hash code is set for the life time of the monitor. 128d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers} 129d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers 1304e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartierint32_t Monitor::GetHashCode() { 1314e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartier while (!HasHashCode()) { 1323e5cf305db800b2989ad57b7cde8fb3cc9fa1b9eIan Rogers if (hash_code_.CompareExchangeWeakRelaxed(0, mirror::Object::GenerateIdentityHashCode())) { 1334e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartier break; 1344e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartier } 1354e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartier } 1364e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartier DCHECK(HasHashCode()); 1373e5cf305db800b2989ad57b7cde8fb3cc9fa1b9eIan Rogers return hash_code_.LoadRelaxed(); 1384e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartier} 1394e6a31eb97f22f4480827474b30b9e64f396eaceMathieu Chartier 140d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogersbool Monitor::Install(Thread* self) { 141d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(self, monitor_lock_); // Uncontended mutex acquisition as monitor isn't yet public. 142ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier CHECK(owner_ == nullptr || owner_ == self || owner_->IsSuspended()); 14300f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Propagate the lock state. 1444cba0d979a11f955e6ec3c0f1bf61478af7aa810Hiroshi Yamauchi LockWord lw(GetObject()->GetLockWord(false)); 145ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier switch (lw.GetState()) { 146ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kThinLocked: { 147ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier CHECK_EQ(owner_->GetThreadId(), lw.ThinLockOwner()); 148ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier lock_count_ = lw.ThinLockCount(); 149ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier break; 150ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 151ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: { 1523e5cf305db800b2989ad57b7cde8fb3cc9fa1b9eIan Rogers CHECK_EQ(hash_code_.LoadRelaxed(), static_cast<int32_t>(lw.GetHashCode())); 153ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier break; 154ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 155ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kFatLocked: { 156ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // The owner_ is suspended but another thread beat us to install a monitor. 157ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier return false; 158ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 159ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kUnlocked: { 160ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier LOG(FATAL) << "Inflating unlocked lock word"; 161ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier break; 162ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 163590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier default: { 164590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier LOG(FATAL) << "Invalid monitor state " << lw.GetState(); 165590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier return false; 166590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 167d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 168e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi LockWord fat(this, lw.ReadBarrierState()); 169d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Publish the updated lock word, which may race with other threads. 170228602f562f1d130d06e60a98752d99c2d467d6aIan Rogers bool success = GetObject()->CasLockWordWeakSequentiallyConsistent(lw, fat); 17100f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Lock profiling. 1729728f91a63016136261231ff5213bde703bd27b6Mathieu Chartier if (success && owner_ != nullptr && lock_profiling_threshold_ != 0) { 1736ec8ebd178ed39aa09e4c7fad194900114c4121aAndreas Gampe // Do not abort on dex pc errors. This can easily happen when we want to dump a stack trace on 1746ec8ebd178ed39aa09e4c7fad194900114c4121aAndreas Gampe // abort. 1756ec8ebd178ed39aa09e4c7fad194900114c4121aAndreas Gampe locking_method_ = owner_->GetCurrentMethod(&locking_dex_pc_, false); 17600f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } 177d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return success; 1785f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 1795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1805f79133a435ebcb20000370d56046fe01201dd80Elliott HughesMonitor::~Monitor() { 181590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // Deflated monitors have a null object. 1825f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 1835f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1845f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::AppendToWaitSet(Thread* thread) { 1855f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(owner_ == Thread::Current()); 1865f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(thread != NULL); 187dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers DCHECK(thread->GetWaitNext() == nullptr) << thread->GetWaitNext(); 1885f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (wait_set_ == NULL) { 1895f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wait_set_ = thread; 1905f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 1915f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 1925f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1935f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // push_back. 1945f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* t = wait_set_; 195dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers while (t->GetWaitNext() != nullptr) { 196dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers t = t->GetWaitNext(); 1975f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 198dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers t->SetWaitNext(thread); 1995f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 2005f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 2015f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::RemoveFromWaitSet(Thread *thread) { 2025f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(owner_ == Thread::Current()); 2035f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(thread != NULL); 2045f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (wait_set_ == NULL) { 2055f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 2065f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 2075f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (wait_set_ == thread) { 208dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers wait_set_ = thread->GetWaitNext(); 209dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers thread->SetWaitNext(nullptr); 2105f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 2115f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 2125f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 2135f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* t = wait_set_; 214dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers while (t->GetWaitNext() != NULL) { 215dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers if (t->GetWaitNext() == thread) { 216dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers t->SetWaitNext(thread->GetWaitNext()); 217dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers thread->SetWaitNext(nullptr); 2185f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 2195f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 220dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers t = t->GetWaitNext(); 2215f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 2225f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 2235f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 2246aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartiervoid Monitor::SetObject(mirror::Object* object) { 22594f7b49578b6aaa80de8ffed230648d601393905Hiroshi Yamauchi obj_ = GcRoot<mirror::Object>(object); 2266aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier} 2276aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier 2285f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::Lock(Thread* self) { 229d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(self, monitor_lock_); 230d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers while (true) { 231440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier if (owner_ == nullptr) { // Unowned. 232d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers owner_ = self; 233d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers CHECK_EQ(lock_count_, 0); 234d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // When debugging, save the current monitor holder for future 235d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // acquisition failures to use in sampled logging. 236d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (lock_profiling_threshold_ != 0) { 237d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers locking_method_ = self->GetCurrentMethod(&locking_dex_pc_); 238fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 239d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; 240d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else if (owner_ == self) { // Recursive. 241d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers lock_count_++; 242d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; 243fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 244d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Contended. 245d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers const bool log_contention = (lock_profiling_threshold_ != 0); 246b894a19dfd668b6779de939cf5265b7e409d8809Xin Guan uint64_t wait_start_ms = log_contention ? MilliTime() : 0; 247ef7d42fca18c16fbaf103822ad16f23246e2905dIan Rogers mirror::ArtMethod* owners_method = locking_method_; 248d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t owners_dex_pc = locking_dex_pc_; 249440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier // Do this before releasing the lock so that we don't get deflated. 250b9001abff3a45f1ae90536da7dd1ec28a6ae0174Mathieu Chartier size_t num_waiters = num_waiters_; 251440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier ++num_waiters_; 252d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Unlock(self); // Let go of locks in order. 253a6e7f0872c42009ecbee82d7fbe452deef9ae65bMathieu Chartier self->SetMonitorEnterObject(GetObject()); 254d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers { 255d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers ScopedThreadStateChange tsc(self, kBlocked); // Change to blocked and give up mutator_lock_. 256d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu2(self, monitor_lock_); // Reacquire monitor_lock_ without mutator_lock_ for Wait. 257f0dc8b5519102b3d3e738aed846975ae4239421eMathieu Chartier if (owner_ != nullptr) { // Did the owner_ give the lock up? 258f0dc8b5519102b3d3e738aed846975ae4239421eMathieu Chartier if (ATRACE_ENABLED()) { 259f0dc8b5519102b3d3e738aed846975ae4239421eMathieu Chartier std::string name; 260f0dc8b5519102b3d3e738aed846975ae4239421eMathieu Chartier owner_->GetThreadName(name); 261f0dc8b5519102b3d3e738aed846975ae4239421eMathieu Chartier ATRACE_BEGIN(("Contended on monitor with owner " + name).c_str()); 262f0dc8b5519102b3d3e738aed846975ae4239421eMathieu Chartier } 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 } 286f0dc8b5519102b3d3e738aed846975ae4239421eMathieu Chartier ATRACE_END(); 287fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 2885f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 289a6e7f0872c42009ecbee82d7fbe452deef9ae65bMathieu Chartier self->SetMonitorEnterObject(nullptr); 290d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Lock(self); // Reacquire locks in order. 291440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier --num_waiters_; 292fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 2935f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 2945f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 2956d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogersstatic void ThrowIllegalMonitorStateExceptionF(const char* fmt, ...) 2966d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers __attribute__((format(printf, 1, 2))); 2976d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers 29800f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogersstatic void ThrowIllegalMonitorStateExceptionF(const char* fmt, ...) 299b726dcb581bf72da46527378ccb6889020f0e6e9Ian Rogers SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3006d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers va_list args; 3016d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers va_start(args, fmt); 30262d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers Thread* self = Thread::Current(); 30362d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers ThrowLocation throw_location = self->GetCurrentLocationForThrow(); 30462d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers self->ThrowNewExceptionV(throw_location, "Ljava/lang/IllegalMonitorStateException;", fmt, args); 305d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (!Runtime::Current()->IsStarted() || VLOG_IS_ON(monitor)) { 30664277f38032208a0c1081ff9e466c04009b96383Brian Carlstrom std::ostringstream ss; 30762d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers self->Dump(ss); 308d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LOG(Runtime::Current()->IsStarted() ? INFO : ERROR) 30914691c5e786e8c2c5734f687e4c96217340771beNicolas Geoffray << self->GetException()->Dump() << "\n" << ss.str(); 31064277f38032208a0c1081ff9e466c04009b96383Brian Carlstrom } 3116d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers va_end(args); 3126d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers} 3136d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers 314d423741f91526cada9d081c64ee295ec9863032dElliott Hughesstatic std::string ThreadToString(Thread* thread) { 315d423741f91526cada9d081c64ee295ec9863032dElliott Hughes if (thread == NULL) { 316d423741f91526cada9d081c64ee295ec9863032dElliott Hughes return "NULL"; 317d423741f91526cada9d081c64ee295ec9863032dElliott Hughes } 318d423741f91526cada9d081c64ee295ec9863032dElliott Hughes std::ostringstream oss; 319d423741f91526cada9d081c64ee295ec9863032dElliott Hughes // TODO: alternatively, we could just return the thread's name. 320d423741f91526cada9d081c64ee295ec9863032dElliott Hughes oss << *thread; 321d423741f91526cada9d081c64ee295ec9863032dElliott Hughes return oss.str(); 322d423741f91526cada9d081c64ee295ec9863032dElliott Hughes} 323d423741f91526cada9d081c64ee295ec9863032dElliott Hughes 3242dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersvoid Monitor::FailedUnlock(mirror::Object* o, Thread* expected_owner, Thread* found_owner, 325ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes Monitor* monitor) { 326ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes Thread* current_owner = NULL; 327ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes std::string current_owner_string; 328ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes std::string expected_owner_string; 329ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes std::string found_owner_string; 330ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes { 331ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes // TODO: isn't this too late to prevent threads from disappearing? 332ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes // Acquire thread list lock so threads won't disappear from under us. 33350b35e2fd1a68cd1240e4a9d9f363e11764957d1Ian Rogers MutexLock mu(Thread::Current(), *Locks::thread_list_lock_); 334ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes // Re-read owner now that we hold lock. 335d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers current_owner = (monitor != NULL) ? monitor->GetOwner() : NULL; 336ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes // Get short descriptions of the threads involved. 337ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes current_owner_string = ThreadToString(current_owner); 338ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string = ThreadToString(expected_owner); 339ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes found_owner_string = ThreadToString(found_owner); 340ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes } 3416d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (current_owner == NULL) { 3426d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (found_owner == NULL) { 3436d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of unowned monitor on object of type '%s'" 3446d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " on thread '%s'", 345ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes PrettyTypeOf(o).c_str(), 346ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string.c_str()); 3476d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 3486d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers // Race: the original read found an owner but now there is none 3496d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor owned by '%s' on object of type '%s'" 3506d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " (where now the monitor appears unowned) on thread '%s'", 351ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes found_owner_string.c_str(), 352ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes PrettyTypeOf(o).c_str(), 353ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string.c_str()); 3546d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 3556d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 3566d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (found_owner == NULL) { 3576d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers // Race: originally there was no owner, there is now 3586d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor owned by '%s' on object of type '%s'" 3596d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " (originally believed to be unowned) on thread '%s'", 360ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes current_owner_string.c_str(), 361ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes PrettyTypeOf(o).c_str(), 362ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string.c_str()); 3636d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 3646d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (found_owner != current_owner) { 3656d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers // Race: originally found and current owner have changed 3666d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor originally owned by '%s' (now" 3676d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " owned by '%s') on object of type '%s' on thread '%s'", 368ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes found_owner_string.c_str(), 369ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes current_owner_string.c_str(), 370ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes PrettyTypeOf(o).c_str(), 371ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string.c_str()); 3726d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 3736d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor owned by '%s' on object of type '%s'" 3746d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " on thread '%s", 375ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes current_owner_string.c_str(), 376ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes PrettyTypeOf(o).c_str(), 377ffb465f23d9549dd591e6aa62e9250523cb00233Elliott Hughes expected_owner_string.c_str()); 3786d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 3796d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 3806d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 3815f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 3825f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 383d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogersbool Monitor::Unlock(Thread* self) { 3845f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 385d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(self, monitor_lock_); 3866d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers Thread* owner = owner_; 3876d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (owner == self) { 3885f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // We own the monitor, so nobody else can be in here. 3895f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (lock_count_ == 0) { 3905f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes owner_ = NULL; 39133dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_method_ = NULL; 3920399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers locking_dex_pc_ = 0; 393d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Wake a contender. 394d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_contenders_.Signal(self); 3955f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 3965f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes --lock_count_; 3975f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 3985f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 3995f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // We don't own this, so we're not allowed to unlock it. 4005f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // The JNI spec says that we should throw IllegalMonitorStateException 4015f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // in this case. 4024cba0d979a11f955e6ec3c0f1bf61478af7aa810Hiroshi Yamauchi FailedUnlock(GetObject(), self, owner, this); 4035f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return false; 4045f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 4055f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return true; 4065f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 4075f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4084cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughesvoid Monitor::Wait(Thread* self, int64_t ms, int32_t ns, 4094cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes bool interruptShouldThrow, ThreadState why) { 4105f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 4114cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes DCHECK(why == kTimedWaiting || why == kWaiting || why == kSleeping); 4125f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 413d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Lock(self); 414d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers 4155f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Make sure that we hold the lock. 4165f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (owner_ != self) { 417d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Unlock(self); 4181af6a1fa35ff7dc0a5c653f19dbc8a91c914aa42Elena Sayapina ThrowIllegalMonitorStateExceptionF("object not locked by thread before wait()"); 4195f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 4205f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 4214cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes 422df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes // We need to turn a zero-length timed wait into a regular wait because 423df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes // Object.wait(0, 0) is defined as Object.wait(0), which is defined as Object.wait(). 424df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes if (why == kTimedWaiting && (ms == 0 && ns == 0)) { 425df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes why = kWaiting; 426df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes } 427df42c4815c30b9df15aacb88070c1e94f41d0226Elliott Hughes 4285f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Enforce the timeout range. 4295f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (ms < 0 || ns < 0 || ns > 999999) { 4301af6a1fa35ff7dc0a5c653f19dbc8a91c914aa42Elena Sayapina monitor_lock_.Unlock(self); 43162d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers ThrowLocation throw_location = self->GetCurrentLocationForThrow(); 43262d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers self->ThrowNewExceptionF(throw_location, "Ljava/lang/IllegalArgumentException;", 433ef7d42fca18c16fbaf103822ad16f23246e2905dIan Rogers "timeout arguments out of range: ms=%" PRId64 " ns=%d", ms, ns); 4345f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 4355f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 4365f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 4385f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Add ourselves to the set of threads waiting on this monitor, and 4395f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * release our hold. We need to let it go even if we're a few levels 4405f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * deep in a recursive lock, and we need to restore that later. 4415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 4425f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * We append to the wait set ahead of clearing the count and owner 4435f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * fields so the subroutine can check that the calling thread owns 4445f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * the monitor. Aside from that, the order of member updates is 4455f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * not order sensitive as we hold the pthread mutex. 4465f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 4475f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes AppendToWaitSet(self); 448440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier ++num_waiters_; 4490399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers int prev_lock_count = lock_count_; 4505f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes lock_count_ = 0; 4515f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes owner_ = NULL; 452ef7d42fca18c16fbaf103822ad16f23246e2905dIan Rogers mirror::ArtMethod* saved_method = locking_method_; 45333dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_method_ = NULL; 4540399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers uintptr_t saved_dex_pc = locking_dex_pc_; 4550399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers locking_dex_pc_ = 0; 4565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 4584cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes * Update thread state. If the GC wakes up, it'll ignore us, knowing 4595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * that we won't touch any references in this state, and we'll check 4605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * our suspend mode before we transition out. 4615f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 4624cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes self->TransitionFromRunnableToSuspended(why); 4635f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 464b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes bool was_interrupted = false; 46500f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers { 46600f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Pseudo-atomically wait on self's wait_cond_ and release the monitor lock. 467dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers MutexLock mu(self, *self->GetWaitMutex()); 4685f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 46900f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Set wait_monitor_ to the monitor object we will be waiting on. When wait_monitor_ is 47000f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // non-NULL a notifying or interrupting thread must signal the thread's wait_cond_ to wake it 47100f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // up. 472dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers DCHECK(self->GetWaitMonitor() == nullptr); 473dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->SetWaitMonitor(this); 4745f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 47500f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Release the monitor lock. 476d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_contenders_.Signal(self); 477d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Unlock(self); 47800f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers 479b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes // Handle the case where the thread was interrupted before we called wait(). 480dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers if (self->IsInterruptedLocked()) { 481b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes was_interrupted = true; 48200f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } else { 48300f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Wait for a notification or a timeout to occur. 4844cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes if (why == kWaiting) { 485dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->GetWaitConditionVariable()->Wait(self); 48600f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } else { 4874cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes DCHECK(why == kTimedWaiting || why == kSleeping) << why; 488dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->GetWaitConditionVariable()->TimedWait(self, ms, ns); 48900f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } 490dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers if (self->IsInterruptedLocked()) { 491b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes was_interrupted = true; 49200f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } 493dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->SetInterruptedLocked(false); 49400f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } 4955f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 4965f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 49700f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers // Set self->status back to kRunnable, and self-suspend if needed. 49800f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers self->TransitionFromSuspendedToRunnable(); 4995f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 500b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes { 501b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes // We reset the thread's wait_monitor_ field after transitioning back to runnable so 502b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes // that a thread in a waiting/sleeping state has a non-null wait_monitor_ for debugging 503b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes // and diagnostic purposes. (If you reset this earlier, stack dumps will claim that threads 504b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes // are waiting on "null".) 505dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers MutexLock mu(self, *self->GetWaitMutex()); 506dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers DCHECK(self->GetWaitMonitor() != nullptr); 507dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->SetWaitMonitor(nullptr); 508b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes } 509b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes 510d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Re-acquire the monitor and lock. 51100f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers Lock(self); 512d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers monitor_lock_.Lock(self); 513dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->GetWaitMutex()->AssertNotHeld(self); 5145f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5155f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 5165f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * We remove our thread from wait set after restoring the count 5175f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * and owner fields so the subroutine can check that the calling 5185f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * thread owns the monitor. Aside from that, the order of member 5195f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * updates is not order sensitive as we hold the pthread mutex. 5205f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 5215f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes owner_ = self; 5220399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers lock_count_ = prev_lock_count; 5230399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers locking_method_ = saved_method; 5240399dde18753aa9bd2bd0d7cf60beef154d164a4Ian Rogers locking_dex_pc_ = saved_dex_pc; 525440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier --num_waiters_; 5265f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes RemoveFromWaitSet(self); 5275f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5281af6a1fa35ff7dc0a5c653f19dbc8a91c914aa42Elena Sayapina monitor_lock_.Unlock(self); 5291af6a1fa35ff7dc0a5c653f19dbc8a91c914aa42Elena Sayapina 530b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes if (was_interrupted) { 5315f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 5325f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * We were interrupted while waiting, or somebody interrupted an 5335f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * un-interruptible thread earlier and we're bailing out immediately. 5345f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 5355f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The doc sayeth: "The interrupted status of the current thread is 5365f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * cleared when this exception is thrown." 5375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 53800f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers { 539dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers MutexLock mu(self, *self->GetWaitMutex()); 540dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->SetInterruptedLocked(false); 54100f7d0eaa6bd93d33bf0c1429bf4ba0b3f28abacIan Rogers } 5425f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (interruptShouldThrow) { 54362d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers ThrowLocation throw_location = self->GetCurrentLocationForThrow(); 54462d6c772205b8859f0ebf7ad105402ec4c3e2e01Ian Rogers self->ThrowNewException(throw_location, "Ljava/lang/InterruptedException;", NULL); 5455f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5465f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5475f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 5485f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5495f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::Notify(Thread* self) { 5505f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 551d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(self, monitor_lock_); 5525f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Make sure that we hold the lock. 5535f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (owner_ != self) { 5546d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notify()"); 5555f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 5565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Signal the first waiting thread in the wait set. 5585f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes while (wait_set_ != NULL) { 5595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* thread = wait_set_; 560dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers wait_set_ = thread->GetWaitNext(); 561dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers thread->SetWaitNext(nullptr); 5625f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5635f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Check to see if the thread is still waiting. 564277ccbd200ea43590dfc06a93ae184a765327ad0Andreas Gampe MutexLock wait_mu(self, *thread->GetWaitMutex()); 565dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers if (thread->GetWaitMonitor() != nullptr) { 566dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers thread->GetWaitConditionVariable()->Signal(self); 5675f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 5685f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5695f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5705f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 5715f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5725f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::NotifyAll(Thread* self) { 5735f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 574d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(self, monitor_lock_); 5755f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Make sure that we hold the lock. 5765f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (owner_ != self) { 5776d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notifyAll()"); 5785f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 5795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5805f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Signal all threads in the wait set. 5815f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes while (wait_set_ != NULL) { 5825f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* thread = wait_set_; 583dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers wait_set_ = thread->GetWaitNext(); 584dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers thread->SetWaitNext(nullptr); 5855f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thread->Notify(); 5865f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5875f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 5885f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 589590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartierbool Monitor::Deflate(Thread* self, mirror::Object* obj) { 590590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier DCHECK(obj != nullptr); 5914d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier // Don't need volatile since we only deflate with mutators suspended. 5924d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier LockWord lw(obj->GetLockWord(false)); 593590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // If the lock isn't an inflated monitor, then we don't need to deflate anything. 594590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier if (lw.GetState() == LockWord::kFatLocked) { 595590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier Monitor* monitor = lw.FatLockMonitor(); 596440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier DCHECK(monitor != nullptr); 597590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier MutexLock mu(self, monitor->monitor_lock_); 598440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier // Can't deflate if we have anybody waiting on the CV. 599440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier if (monitor->num_waiters_ > 0) { 600440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier return false; 601440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier } 602590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier Thread* owner = monitor->owner_; 603590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier if (owner != nullptr) { 604590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // Can't deflate if we are locked and have a hash code. 605590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier if (monitor->HasHashCode()) { 606590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier return false; 607590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 608590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // Can't deflate if our lock count is too high. 609590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier if (monitor->lock_count_ > LockWord::kThinLockMaxCount) { 610590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier return false; 611590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 612590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // Deflate to a thin lock. 613e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi LockWord new_lw = LockWord::FromThinLockId(owner->GetThreadId(), monitor->lock_count_, 614e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi lw.ReadBarrierState()); 615e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi // Assume no concurrent read barrier state changes as mutators are suspended. 616e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi obj->SetLockWord(new_lw, false); 6174d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier VLOG(monitor) << "Deflated " << obj << " to thin lock " << owner->GetTid() << " / " 6184d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier << monitor->lock_count_; 619590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } else if (monitor->HasHashCode()) { 620e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi LockWord new_lw = LockWord::FromHashCode(monitor->GetHashCode(), lw.ReadBarrierState()); 621e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi // Assume no concurrent read barrier state changes as mutators are suspended. 622e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi obj->SetLockWord(new_lw, false); 623440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier VLOG(monitor) << "Deflated " << obj << " to hash monitor " << monitor->GetHashCode(); 624590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } else { 625590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // No lock and no hash, just put an empty lock word inside the object. 626e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi LockWord new_lw = LockWord::FromDefault(lw.ReadBarrierState()); 627e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi // Assume no concurrent read barrier state changes as mutators are suspended. 628e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi obj->SetLockWord(new_lw, false); 629440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier VLOG(monitor) << "Deflated" << obj << " to empty lock word"; 630590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 631590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // The monitor is deflated, mark the object as nullptr so that we know to delete it during the 632590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // next GC. 63394f7b49578b6aaa80de8ffed230648d601393905Hiroshi Yamauchi monitor->obj_ = GcRoot<mirror::Object>(nullptr); 634590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 635590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier return true; 636590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier} 637590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier 638ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartiervoid Monitor::Inflate(Thread* self, Thread* owner, mirror::Object* obj, int32_t hash_code) { 63974240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe DCHECK(self != nullptr); 64074240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe DCHECK(obj != nullptr); 6415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Allocate and acquire a new monitor. 64274240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe Monitor* m = MonitorPool::CreateMonitor(self, owner, obj, hash_code); 64374240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe DCHECK(m != nullptr); 644d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (m->Install(self)) { 64586ab7912423f63541073af5c487b509e9b2b5420Haifeng Li if (owner != nullptr) { 64686ab7912423f63541073af5c487b509e9b2b5420Haifeng Li VLOG(monitor) << "monitor: thread" << owner->GetThreadId() 64774240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe << " created monitor " << m << " for object " << obj; 64886ab7912423f63541073af5c487b509e9b2b5420Haifeng Li } else { 64986ab7912423f63541073af5c487b509e9b2b5420Haifeng Li VLOG(monitor) << "monitor: Inflate with hashcode " << hash_code 65074240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe << " created monitor " << m << " for object " << obj; 65186ab7912423f63541073af5c487b509e9b2b5420Haifeng Li } 65274240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe Runtime::Current()->GetMonitorList()->Add(m); 6534d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier CHECK_EQ(obj->GetLockWord(true).GetState(), LockWord::kFatLocked); 65474240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe } else { 65574240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe MonitorPool::ReleaseMonitor(self, m); 656ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 657ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier} 658ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier 6590cd81352a7c06e381951cea1b104fd73516f4341Mathieu Chartiervoid Monitor::InflateThinLocked(Thread* self, Handle<mirror::Object> obj, LockWord lock_word, 660ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier uint32_t hash_code) { 661ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier DCHECK_EQ(lock_word.GetState(), LockWord::kThinLocked); 662ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier uint32_t owner_thread_id = lock_word.ThinLockOwner(); 663ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier if (owner_thread_id == self->GetThreadId()) { 664ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // We own the monitor, we can easily inflate it. 665eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier Inflate(self, self, obj.Get(), hash_code); 666ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } else { 667ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier ThreadList* thread_list = Runtime::Current()->GetThreadList(); 668ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Suspend the owner, inflate. First change to blocked and give up mutator_lock_. 669eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier self->SetMonitorEnterObject(obj.Get()); 670a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier bool timed_out; 671a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier Thread* owner; 672a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier { 673a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier ScopedThreadStateChange tsc(self, kBlocked); 674a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier owner = thread_list->SuspendThreadByThreadId(owner_thread_id, false, &timed_out); 675a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier } 676a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier if (owner != nullptr) { 677a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier // We succeeded in suspending the thread, check the lock's status didn't change. 678a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier lock_word = obj->GetLockWord(true); 679a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier if (lock_word.GetState() == LockWord::kThinLocked && 680a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier lock_word.ThinLockOwner() == owner_thread_id) { 681a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier // Go ahead and inflate the lock. 682a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier Inflate(self, owner, obj.Get(), hash_code); 683ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 684a1ee14fc66a3c99bb7d5744ace881ec93c46f59dMathieu Chartier thread_list->Resume(owner, false); 685ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier } 686dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers self->SetMonitorEnterObject(nullptr); 687d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 6885f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 6895f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 690719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers// Fool annotalysis into thinking that the lock on obj is acquired. 691719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogersstatic mirror::Object* FakeLock(mirror::Object* obj) 692719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers EXCLUSIVE_LOCK_FUNCTION(obj) NO_THREAD_SAFETY_ANALYSIS { 693719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers return obj; 694719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers} 695719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers 696719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers// Fool annotalysis into thinking that the lock on obj is release. 697719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogersstatic mirror::Object* FakeUnlock(mirror::Object* obj) 698719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers UNLOCK_FUNCTION(obj) NO_THREAD_SAFETY_ANALYSIS { 699719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers return obj; 700719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers} 701719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers 702e7e8a5fea2d852cccc840fa046151a16627f26cdMathieu Chartiermirror::Object* Monitor::MonitorEnter(Thread* self, mirror::Object* obj) { 7034681c809ba35d50fab92c592ce8d2c7f8b2731f7Elliott Hughes DCHECK(self != NULL); 7044681c809ba35d50fab92c592ce8d2c7f8b2731f7Elliott Hughes DCHECK(obj != NULL); 705719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers obj = FakeLock(obj); 706d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t thread_id = self->GetThreadId(); 707d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers size_t contention_count = 0; 708eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier StackHandleScope<1> hs(self); 709eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier Handle<mirror::Object> h_obj(hs.NewHandle(obj)); 710d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers while (true) { 711eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier LockWord lock_word = h_obj->GetLockWord(true); 712d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 713d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: { 714e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi LockWord thin_locked(LockWord::FromThinLockId(thread_id, 0, lock_word.ReadBarrierState())); 715228602f562f1d130d06e60a98752d99c2d467d6aIan Rogers if (h_obj->CasLockWordWeakSequentiallyConsistent(lock_word, thin_locked)) { 7163035961cb41865b80b927546be0c708b6389cec6Hans Boehm // CasLockWord enforces more than the acquire ordering we need here. 717eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier return h_obj.Get(); // Success! 718d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 719d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers continue; // Go again. 7205f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 721d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: { 722d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t owner_thread_id = lock_word.ThinLockOwner(); 723d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (owner_thread_id == thread_id) { 724d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // We own the lock, increase the recursion count. 725d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t new_count = lock_word.ThinLockCount() + 1; 726d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (LIKELY(new_count <= LockWord::kThinLockMaxCount)) { 727e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi LockWord thin_locked(LockWord::FromThinLockId(thread_id, new_count, 728e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi lock_word.ReadBarrierState())); 729e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi if (!kUseReadBarrier) { 730e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi h_obj->SetLockWord(thin_locked, true); 731e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi return h_obj.Get(); // Success! 732e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi } else { 733e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi // Use CAS to preserve the read barrier state. 734e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi if (h_obj->CasLockWordWeakSequentiallyConsistent(lock_word, thin_locked)) { 735e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi return h_obj.Get(); // Success! 736e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi } 737e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi } 738e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi continue; // Go again. 739d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 740d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // We'd overflow the recursion count, so inflate the monitor. 741eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier InflateThinLocked(self, h_obj, lock_word, 0); 742d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 743d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 744d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Contention. 745d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers contention_count++; 746ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier Runtime* runtime = Runtime::Current(); 747ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier if (contention_count <= runtime->GetMaxSpinsBeforeThinkLockInflation()) { 748b363f666883860d40823d5528df3c98c897f74f4Mathieu Chartier // TODO: Consider switching the thread state to kBlocked when we are yielding. 749251755cd511463260e60be98bf138b6aa1c14bf3Mathieu Chartier // Use sched_yield instead of NanoSleep since NanoSleep can wait much longer than the 750251755cd511463260e60be98bf138b6aa1c14bf3Mathieu Chartier // parameter you pass in. This can cause thread suspension to take excessively long 751b363f666883860d40823d5528df3c98c897f74f4Mathieu Chartier // and make long pauses. See b/16307460. 752251755cd511463260e60be98bf138b6aa1c14bf3Mathieu Chartier sched_yield(); 7535f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 754d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers contention_count = 0; 755eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier InflateThinLocked(self, h_obj, lock_word, 0); 7565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 758d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers continue; // Start from the beginning. 759d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 760d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 761d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 762d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers mon->Lock(self); 763eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier return h_obj.Get(); // Success! 7645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 765719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers case LockWord::kHashCode: 766ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Inflate with the existing hashcode. 767eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier Inflate(self, nullptr, h_obj.Get(), lock_word.GetHashCode()); 768719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers continue; // Start from the beginning. 769590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier default: { 770590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier LOG(FATAL) << "Invalid monitor state " << lock_word.GetState(); 771eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier return h_obj.Get(); 772590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 7735f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7745f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7755f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 7765f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 7772dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersbool Monitor::MonitorExit(Thread* self, mirror::Object* obj) { 7785f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 7795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(obj != NULL); 780719d1a33f6569864f529e5a3fff59e7bca97aad0Ian Rogers obj = FakeUnlock(obj); 781eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier StackHandleScope<1> hs(self); 782eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier Handle<mirror::Object> h_obj(hs.NewHandle(obj)); 783e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi while (true) { 784e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi LockWord lock_word = obj->GetLockWord(true); 785e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi switch (lock_word.GetState()) { 786e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi case LockWord::kHashCode: 787e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi // Fall-through. 788e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi case LockWord::kUnlocked: 789e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi FailedUnlock(h_obj.Get(), self, nullptr, nullptr); 790d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return false; // Failure. 791e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi case LockWord::kThinLocked: { 792e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi uint32_t thread_id = self->GetThreadId(); 793e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi uint32_t owner_thread_id = lock_word.ThinLockOwner(); 794e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi if (owner_thread_id != thread_id) { 795e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi // TODO: there's a race here with the owner dying while we unlock. 796e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi Thread* owner = 797e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi Runtime::Current()->GetThreadList()->FindThreadByThreadId(lock_word.ThinLockOwner()); 798e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi FailedUnlock(h_obj.Get(), self, owner, nullptr); 799e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi return false; // Failure. 800d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 801e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi // We own the lock, decrease the recursion count. 802e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi LockWord new_lw = LockWord::Default(); 803e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi if (lock_word.ThinLockCount() != 0) { 804e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi uint32_t new_count = lock_word.ThinLockCount() - 1; 805e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi new_lw = LockWord::FromThinLockId(thread_id, new_count, lock_word.ReadBarrierState()); 806e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi } else { 807e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi new_lw = LockWord::FromDefault(lock_word.ReadBarrierState()); 808e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi } 809e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi if (!kUseReadBarrier) { 810e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi DCHECK_EQ(new_lw.ReadBarrierState(), 0U); 811e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi h_obj->SetLockWord(new_lw, true); 812e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi // Success! 813e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi return true; 814e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi } else { 815e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi // Use CAS to preserve the read barrier state. 816e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi if (h_obj->CasLockWordWeakSequentiallyConsistent(lock_word, new_lw)) { 817e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi // Success! 818e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi return true; 819e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi } 820e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi } 821e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi continue; // Go again. 822d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 8235f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 824e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi case LockWord::kFatLocked: { 825e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi Monitor* mon = lock_word.FatLockMonitor(); 826e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi return mon->Unlock(self); 827e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi } 828e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi default: { 829e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi LOG(FATAL) << "Invalid monitor state " << lock_word.GetState(); 830e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi return false; 831e15ea086439b41a805d164d2beb07b4ba96aaa97Hiroshi Yamauchi } 832590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 8335f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 8345f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 8355f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 8362dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersvoid Monitor::Wait(Thread* self, mirror::Object *obj, int64_t ms, int32_t ns, 8374cd121ef0cb35fced70c7d9de378277be7a727d9Elliott Hughes bool interruptShouldThrow, ThreadState why) { 8384d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier DCHECK(self != nullptr); 8394d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier DCHECK(obj != nullptr); 8404d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier LockWord lock_word = obj->GetLockWord(true); 84143c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers while (lock_word.GetState() != LockWord::kFatLocked) { 84243c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers switch (lock_word.GetState()) { 84343c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers case LockWord::kHashCode: 84443c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers // Fall-through. 84543c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers case LockWord::kUnlocked: 846d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before wait()"); 847d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Failure. 84843c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers case LockWord::kThinLocked: { 84943c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers uint32_t thread_id = self->GetThreadId(); 85043c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers uint32_t owner_thread_id = lock_word.ThinLockOwner(); 85143c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers if (owner_thread_id != thread_id) { 85243c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before wait()"); 85343c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers return; // Failure. 85443c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers } else { 85543c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers // We own the lock, inflate to enqueue ourself on the Monitor. May fail spuriously so 85643c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers // re-load. 85743c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers Inflate(self, self, obj, 0); 85843c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers lock_word = obj->GetLockWord(true); 85943c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers } 86043c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers break; 86143c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers } 86243c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers case LockWord::kFatLocked: // Unreachable given the loop condition above. Fall-through. 86343c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers default: { 86443c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers LOG(FATAL) << "Invalid monitor state " << lock_word.GetState(); 86543c69cc4cea794cd4d89d9d0680b1e25c6d02accIan Rogers return; 866d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 867590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 8685f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 869d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 870d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers mon->Wait(self, ms, ns, interruptShouldThrow, why); 8715f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 8725f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 87313c479e7e9b62115fe0409e5273c1e976a1c09f9Ian Rogersvoid Monitor::DoNotify(Thread* self, mirror::Object* obj, bool notify_all) { 8744d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier DCHECK(self != nullptr); 8754d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier DCHECK(obj != nullptr); 8764d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier LockWord lock_word = obj->GetLockWord(true); 877d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 878ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: 879ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Fall-through. 880d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: 8816d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notify()"); 882d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Failure. 883d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: { 884d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t thread_id = self->GetThreadId(); 885d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t owner_thread_id = lock_word.ThinLockOwner(); 886d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (owner_thread_id != thread_id) { 887d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notify()"); 888d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Failure. 889d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 890d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // We own the lock but there's no Monitor and therefore no waiters. 891d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Success. 892d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 893d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 894d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 895d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 896d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (notify_all) { 897d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers mon->NotifyAll(self); 898d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 899d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers mon->Notify(self); 900d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 901d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return; // Success. 9025f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 903590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier default: { 904590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier LOG(FATAL) << "Invalid monitor state " << lock_word.GetState(); 905590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier return; 906590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 9075f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 9085f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 9095f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 910d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogersuint32_t Monitor::GetLockOwnerThreadId(mirror::Object* obj) { 9114d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier DCHECK(obj != nullptr); 9124d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier LockWord lock_word = obj->GetLockWord(true); 913d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 914ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: 915ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Fall-through. 916d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: 917d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return ThreadList::kInvalidThreadId; 918d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: 919d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return lock_word.ThinLockOwner(); 920d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 921d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 922d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return mon->GetOwnerThreadId(); 9235f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 924590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier default: { 925d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LOG(FATAL) << "Unreachable"; 9262c4257be8191c5eefde744e8965fcefc80a0a97dIan Rogers UNREACHABLE(); 927590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier } 9285f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 9295f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 9305f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 9318e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughesvoid Monitor::DescribeWait(std::ostream& os, const Thread* thread) { 932d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers // Determine the wait message and object we're waiting or blocked upon. 933d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers mirror::Object* pretty_object = nullptr; 934d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers const char* wait_message = nullptr; 935d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers uint32_t lock_owner = ThreadList::kInvalidThreadId; 936d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers ThreadState state = thread->GetState(); 937b4e94fd380a84c755264e8668a16052442c7ec32Elliott Hughes if (state == kWaiting || state == kTimedWaiting || state == kSleeping) { 938d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers wait_message = (state == kSleeping) ? " - sleeping on " : " - waiting on "; 939d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers Thread* self = Thread::Current(); 940d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers MutexLock mu(self, *thread->GetWaitMutex()); 941d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers Monitor* monitor = thread->GetWaitMonitor(); 942d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers if (monitor != nullptr) { 9434cba0d979a11f955e6ec3c0f1bf61478af7aa810Hiroshi Yamauchi pretty_object = monitor->GetObject(); 9448e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 94534e069606d6f1698cd3c33b39e72b79ae27e1c7bElliott Hughes } else if (state == kBlocked) { 946d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers wait_message = " - waiting to lock "; 947d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers pretty_object = thread->GetMonitorEnterObject(); 948d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers if (pretty_object != nullptr) { 949d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers lock_owner = pretty_object->GetLockOwnerThreadId(); 9508e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 9518e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 9528e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes 953d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers if (wait_message != nullptr) { 954d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers if (pretty_object == nullptr) { 955d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers os << wait_message << "an unknown object"; 956d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers } else { 9574d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier if ((pretty_object->GetLockWord(true).GetState() == LockWord::kThinLocked) && 958d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers Locks::mutator_lock_->IsExclusiveHeld(Thread::Current())) { 959d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers // Getting the identity hashcode here would result in lock inflation and suspension of the 960d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers // current thread, which isn't safe if this is the only runnable thread. 961d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers os << wait_message << StringPrintf("<@addr=0x%" PRIxPTR "> (a %s)", 962d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers reinterpret_cast<intptr_t>(pretty_object), 963d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers PrettyTypeOf(pretty_object).c_str()); 964d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers } else { 965d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers // - waiting on <0x6008c468> (a java.lang.Class<java.lang.ref.ReferenceQueue>) 9664936159997132d7706d9700c646f35ef0283df4bMathieu Chartier // Call PrettyTypeOf before IdentityHashCode since IdentityHashCode can cause thread 9674936159997132d7706d9700c646f35ef0283df4bMathieu Chartier // suspension and move pretty_object. 9684936159997132d7706d9700c646f35ef0283df4bMathieu Chartier const std::string pretty_type(PrettyTypeOf(pretty_object)); 969d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers os << wait_message << StringPrintf("<0x%08x> (a %s)", pretty_object->IdentityHashCode(), 9704936159997132d7706d9700c646f35ef0283df4bMathieu Chartier pretty_type.c_str()); 971d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers } 972d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers } 973d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers // - waiting to lock <0x613f83d8> (a java.lang.Object) held by thread 5 974d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers if (lock_owner != ThreadList::kInvalidThreadId) { 975d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers os << " held by thread " << lock_owner; 976d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers } 977d803bc7ce255be6c16eaf6a8a58a742515e9da9fIan Rogers os << "\n"; 9788e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 9798e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes} 9808e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes 9812dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersmirror::Object* Monitor::GetContendedMonitor(Thread* thread) { 982f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes // This is used to implement JDWP's ThreadReference.CurrentContendedMonitor, and has a bizarre 983f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes // definition of contended that includes a monitor a thread is trying to enter... 984dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers mirror::Object* result = thread->GetMonitorEnterObject(); 985d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (result == NULL) { 986d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // ...but also a monitor that the thread is waiting on. 987dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers MutexLock mu(Thread::Current(), *thread->GetWaitMutex()); 988dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers Monitor* monitor = thread->GetWaitMonitor(); 989f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes if (monitor != NULL) { 990d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers result = monitor->GetObject(); 991f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes } 992f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes } 993d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return result; 994f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes} 995f9501700f51586cb6ba7cc0ffcb5a920bd64adf1Elliott Hughes 9962dd0e2cea360bc9206eb88ecc40d259e796c239dIan Rogersvoid Monitor::VisitLocks(StackVisitor* stack_visitor, void (*callback)(mirror::Object*, void*), 997760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe void* callback_context, bool abort_on_failure) { 998ea46f950e7a51585db293cd7f047de190a482414Brian Carlstrom mirror::ArtMethod* m = stack_visitor->GetMethod(); 99908fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes CHECK(m != NULL); 100008fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 100108fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes // Native methods are an easy special case. 100208fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes // TODO: use the JNI implementation's table of explicit MonitorEnter calls and dump those too. 100308fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes if (m->IsNative()) { 100408fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes if (m->IsSynchronized()) { 1005eb8167a4f4d27fce0530f6724ab8032610cd146bMathieu Chartier mirror::Object* jni_this = stack_visitor->GetCurrentHandleScope()->GetReference(0); 10064993bbc8eda377804e585efd918f8ab9d9eab7d4Elliott Hughes callback(jni_this, callback_context); 100708fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 100808fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes return; 100908fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 101008fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 101161f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao // Proxy methods should not be synchronized. 101261f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao if (m->IsProxyMethod()) { 101361f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao CHECK(!m->IsSynchronized()); 101461f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao return; 101561f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao } 101661f916cc4757610ce308bfdea9a00cf29afd2b02jeffhao 101708fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes // Is there any reason to believe there's any synchronization in this method? 1018bfd9a4378eacaf2dc2bbe05ad48c5164fc93c9feMathieu Chartier const DexFile::CodeItem* code_item = m->GetCodeItem(); 1019caf7654a0e6c76c7489970b1a246fccf220f9982Elliott Hughes CHECK(code_item != NULL) << PrettyMethod(m); 102008fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes if (code_item->tries_size_ == 0) { 10217934ac288acfb2552bb0b06ec1f61e5820d924a4Brian Carlstrom return; // No "tries" implies no synchronization, so no held locks to report. 102208fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 102308fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 1024760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe // Get the dex pc. If abort_on_failure is false, GetDexPc will not abort in the case it cannot 1025760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe // find the dex pc, and instead return kDexNoIndex. Then bail out, as it indicates we have an 1026760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe // inconsistent stack anyways. 1027760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe uint32_t dex_pc = stack_visitor->GetDexPc(abort_on_failure); 1028760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe if (!abort_on_failure && dex_pc == DexFile::kDexNoIndex) { 1029760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe LOG(ERROR) << "Could not find dex_pc for " << PrettyMethod(m); 1030760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe return; 1031760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe } 1032760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe 103380537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes // Ask the verifier for the dex pcs of all the monitor-enter instructions corresponding to 103480537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes // the locks held in this stack frame. 103580537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes std::vector<uint32_t> monitor_enter_dex_pcs; 1036760172c3ccd6e75f6f1a89d8006934e8ffb1303eAndreas Gampe verifier::MethodVerifier::FindLocksAtDexPc(m, dex_pc, &monitor_enter_dex_pcs); 1037e6a8eec3a5db28de7d5db6d78e38033b80740e49Mathieu Chartier for (uint32_t monitor_dex_pc : monitor_enter_dex_pcs) { 103880537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes // The verifier works in terms of the dex pcs of the monitor-enter instructions. 103980537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes // We want the registers used by those instructions (so we can read the values out of them). 1040277ccbd200ea43590dfc06a93ae184a765327ad0Andreas Gampe uint16_t monitor_enter_instruction = code_item->insns_[monitor_dex_pc]; 104108fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 104280537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes // Quick sanity check. 104380537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes if ((monitor_enter_instruction & 0xff) != Instruction::MONITOR_ENTER) { 1044277ccbd200ea43590dfc06a93ae184a765327ad0Andreas Gampe LOG(FATAL) << "expected monitor-enter @" << monitor_dex_pc << "; was " 104580537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes << reinterpret_cast<void*>(monitor_enter_instruction); 104608fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 104780537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes 104880537bb742dff4ccdf6d04b1c0bb7d2179acc8cbElliott Hughes uint16_t monitor_register = ((monitor_enter_instruction >> 8) & 0xff); 1049e6a8eec3a5db28de7d5db6d78e38033b80740e49Mathieu Chartier mirror::Object* o = reinterpret_cast<mirror::Object*>( 1050e6a8eec3a5db28de7d5db6d78e38033b80740e49Mathieu Chartier stack_visitor->GetVReg(m, monitor_register, kReferenceVReg)); 10514993bbc8eda377804e585efd918f8ab9d9eab7d4Elliott Hughes callback(o, callback_context); 105208fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes } 105308fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes} 105408fc03ae5dded4adc9b45b7014a4b9dfedbe95a6Elliott Hughes 1055d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogersbool Monitor::IsValidLockWord(LockWord lock_word) { 1056d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 1057d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: 1058d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Nothing to check. 1059d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return true; 1060d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: 1061d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Basic sanity check of owner. 1062d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return lock_word.ThinLockOwner() != ThreadList::kInvalidThreadId; 1063d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 1064d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Check the monitor appears in the monitor list. 1065d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 1066d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MonitorList* list = Runtime::Current()->GetMonitorList(); 1067d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(Thread::Current(), list->monitor_list_lock_); 1068d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers for (Monitor* list_mon : list->list_) { 1069d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (mon == list_mon) { 1070d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return true; // Found our monitor. 1071d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 10727dfb28c066159e6cde8181720f0c451a700ef966Ian Rogers } 1073d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return false; // Fail - unowned monitor in an object. 10747dfb28c066159e6cde8181720f0c451a700ef966Ian Rogers } 1075ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: 1076ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier return true; 1077d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers default: 1078d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers LOG(FATAL) << "Unreachable"; 10792c4257be8191c5eefde744e8965fcefc80a0a97dIan Rogers UNREACHABLE(); 10807dfb28c066159e6cde8181720f0c451a700ef966Ian Rogers } 10817dfb28c066159e6cde8181720f0c451a700ef966Ian Rogers} 10827dfb28c066159e6cde8181720f0c451a700ef966Ian Rogers 1083ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartierbool Monitor::IsLocked() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1084ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier MutexLock mu(Thread::Current(), monitor_lock_); 1085ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier return owner_ != nullptr; 1086ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier} 1087ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier 1088ef7d42fca18c16fbaf103822ad16f23246e2905dIan Rogersvoid Monitor::TranslateLocation(mirror::ArtMethod* method, uint32_t dex_pc, 1089d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers const char** source_file, uint32_t* line_number) const { 109033dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao // If method is null, location is unknown 109133dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao if (method == NULL) { 1092d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers *source_file = ""; 1093d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers *line_number = 0; 109433dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao return; 109533dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao } 1096bfd9a4378eacaf2dc2bbe05ad48c5164fc93c9feMathieu Chartier *source_file = method->GetDeclaringClassSourceFile(); 1097d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (*source_file == NULL) { 1098d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers *source_file = ""; 1099d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 1100bfd9a4378eacaf2dc2bbe05ad48c5164fc93c9feMathieu Chartier *line_number = method->GetLineNumFromDexPC(dex_pc); 1101d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers} 1102d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers 1103d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogersuint32_t Monitor::GetOwnerThreadId() { 1104d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers MutexLock mu(Thread::Current(), monitor_lock_); 1105d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Thread* owner = owner_; 1106d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers if (owner != NULL) { 1107d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return owner->GetThreadId(); 1108d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } else { 1109d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers return ThreadList::kInvalidThreadId; 111012c51e3e5a8b5655351539618f1cf2331f52d1abElliott Hughes } 111133dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao} 111233dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao 1113c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu ChartierMonitorList::MonitorList() 1114440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier : allow_new_monitors_(true), monitor_list_lock_("MonitorList lock", kMonitorListLock), 1115c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier monitor_add_condition_("MonitorList disallow condition", monitor_list_lock_) { 1116c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 1117c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 1118c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott HughesMonitorList::~MonitorList() { 111974240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe Thread* self = Thread::Current(); 112074240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe MutexLock mu(self, monitor_list_lock_); 112174240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe // Release all monitors to the pool. 112274240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe // TODO: Is it an invariant that *all* open monitors are in the list? Then we could 112374240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe // clear faster in the pool. 112474240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe MonitorPool::ReleaseMonitors(self, &list_); 1125c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 1126c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 1127c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartiervoid MonitorList::DisallowNewMonitors() { 112850b35e2fd1a68cd1240e4a9d9f363e11764957d1Ian Rogers MutexLock mu(Thread::Current(), monitor_list_lock_); 1129c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier allow_new_monitors_ = false; 1130c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier} 1131c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier 1132c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartiervoid MonitorList::AllowNewMonitors() { 1133c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier Thread* self = Thread::Current(); 1134c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier MutexLock mu(self, monitor_list_lock_); 1135c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier allow_new_monitors_ = true; 1136c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier monitor_add_condition_.Broadcast(self); 1137c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier} 1138c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier 11392cd334ae2d4287216523882f0d298cf3901b7ab1Hiroshi Yamauchivoid MonitorList::EnsureNewMonitorsDisallowed() { 11402cd334ae2d4287216523882f0d298cf3901b7ab1Hiroshi Yamauchi // Lock and unlock once to ensure that no threads are still in the 11412cd334ae2d4287216523882f0d298cf3901b7ab1Hiroshi Yamauchi // middle of adding new monitors. 11422cd334ae2d4287216523882f0d298cf3901b7ab1Hiroshi Yamauchi MutexLock mu(Thread::Current(), monitor_list_lock_); 11432cd334ae2d4287216523882f0d298cf3901b7ab1Hiroshi Yamauchi CHECK(!allow_new_monitors_); 11442cd334ae2d4287216523882f0d298cf3901b7ab1Hiroshi Yamauchi} 11452cd334ae2d4287216523882f0d298cf3901b7ab1Hiroshi Yamauchi 1146c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartiervoid MonitorList::Add(Monitor* m) { 1147c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier Thread* self = Thread::Current(); 1148c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier MutexLock mu(self, monitor_list_lock_); 1149c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier while (UNLIKELY(!allow_new_monitors_)) { 1150c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier monitor_add_condition_.WaitHoldingLocks(self); 1151c11d9b8870de5f860b13c84003ade7b3f3125a52Mathieu Chartier } 1152c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes list_.push_front(m); 1153c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 1154c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 115583c8ee000d525017ead8753fce6bc1020249b96aMathieu Chartiervoid MonitorList::SweepMonitorList(IsMarkedCallback* callback, void* arg) { 115674240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe Thread* self = Thread::Current(); 115774240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe MutexLock mu(self, monitor_list_lock_); 115802e25119b15a6f619f17db99f5d05124a5807ff3Mathieu Chartier for (auto it = list_.begin(); it != list_.end(); ) { 1159c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes Monitor* m = *it; 11604cba0d979a11f955e6ec3c0f1bf61478af7aa810Hiroshi Yamauchi // Disable the read barrier in GetObject() as this is called by GC. 11614cba0d979a11f955e6ec3c0f1bf61478af7aa810Hiroshi Yamauchi mirror::Object* obj = m->GetObject<kWithoutReadBarrier>(); 1162590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // The object of a monitor can be null if we have deflated it. 116383c8ee000d525017ead8753fce6bc1020249b96aMathieu Chartier mirror::Object* new_obj = obj != nullptr ? callback(obj, arg) : nullptr; 11646aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier if (new_obj == nullptr) { 11656aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier VLOG(monitor) << "freeing monitor " << m << " belonging to unmarked object " 11664cba0d979a11f955e6ec3c0f1bf61478af7aa810Hiroshi Yamauchi << obj; 116774240819ae09e29b2753ef38f4eb4be1c2762e2eAndreas Gampe MonitorPool::ReleaseMonitor(self, m); 1168c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes it = list_.erase(it); 1169c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes } else { 11706aa3df965395566ed6a4fec4af37c2b7577992e9Mathieu Chartier m->SetObject(new_obj); 1171c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes ++it; 1172c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes } 1173c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes } 1174c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 1175c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 117648ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartierstruct MonitorDeflateArgs { 117748ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier MonitorDeflateArgs() : self(Thread::Current()), deflate_count(0) {} 117848ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier Thread* const self; 117948ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier size_t deflate_count; 118048ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier}; 118148ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier 1182440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartierstatic mirror::Object* MonitorDeflateCallback(mirror::Object* object, void* arg) 1183440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 118448ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier MonitorDeflateArgs* args = reinterpret_cast<MonitorDeflateArgs*>(arg); 118548ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier if (Monitor::Deflate(args->self, object)) { 11864d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier DCHECK_NE(object->GetLockWord(true).GetState(), LockWord::kFatLocked); 118748ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier ++args->deflate_count; 1188440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier // If we deflated, return nullptr so that the monitor gets removed from the array. 1189440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier return nullptr; 1190440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier } 1191440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier return object; // Monitor was not deflated. 1192440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier} 1193440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier 119448ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartiersize_t MonitorList::DeflateMonitors() { 119548ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier MonitorDeflateArgs args; 119648ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier Locks::mutator_lock_->AssertExclusiveHeld(args.self); 119748ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier SweepMonitorList(MonitorDeflateCallback, &args); 119848ab687d1f864fec93c2682de6fdc44ab784e2f8Mathieu Chartier return args.deflate_count; 1199440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier} 1200440e4ceb310349ee8eb569495bc04d3d7fbe71cbMathieu Chartier 1201d9c4fc94fa618617f94e1de9af5f034549100753Ian RogersMonitorInfo::MonitorInfo(mirror::Object* obj) : owner_(NULL), entry_count_(0) { 12024d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier DCHECK(obj != nullptr); 12034d7f61d44a732cfbc8573e5d93364983fd746888Mathieu Chartier LockWord lock_word = obj->GetLockWord(true); 1204d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers switch (lock_word.GetState()) { 1205d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kUnlocked: 1206ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier // Fall-through. 1207590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier case LockWord::kForwardingAddress: 1208590fee9e8972f872301c2d16a575d579ee564beeMathieu Chartier // Fall-through. 1209ad2541a59c00c2c69e8973088891a2b5257c9780Mathieu Chartier case LockWord::kHashCode: 1210d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers break; 1211d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kThinLocked: 1212d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers owner_ = Runtime::Current()->GetThreadList()->FindThreadByThreadId(lock_word.ThinLockOwner()); 1213d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers entry_count_ = 1 + lock_word.ThinLockCount(); 1214d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers // Thin locks have no waiters. 1215d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers break; 1216d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers case LockWord::kFatLocked: { 1217d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers Monitor* mon = lock_word.FatLockMonitor(); 1218d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers owner_ = mon->owner_; 1219d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers entry_count_ = 1 + mon->lock_count_; 1220dd7624d2b9e599d57762d12031b10b89defc9807Ian Rogers for (Thread* waiter = mon->wait_set_; waiter != NULL; waiter = waiter->GetWaitNext()) { 1221d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers waiters_.push_back(waiter); 1222d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers } 1223d9c4fc94fa618617f94e1de9af5f034549100753Ian Rogers break; 1224f327e07b37e349b1ec5eaad6dc294a9b7a081d20Elliott Hughes } 1225f327e07b37e349b1ec5eaad6dc294a9b7a081d20Elliott Hughes } 1226f327e07b37e349b1ec5eaad6dc294a9b7a081d20Elliott Hughes} 1227f327e07b37e349b1ec5eaad6dc294a9b7a081d20Elliott Hughes 12285f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} // namespace art 1229