monitor.cc revision d423741f91526cada9d081c64ee295ec9863032d
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 195f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#include <errno.h> 205f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#include <fcntl.h> 215f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#include <pthread.h> 225f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#include <stdlib.h> 235f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#include <sys/time.h> 245f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#include <time.h> 255f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#include <unistd.h> 265f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 2733dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao#include "class_linker.h" 285f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#include "mutex.h" 295f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#include "object.h" 306d4d9fcb4f01e287ee29e81cd1c941ee5d11d379Ian Rogers#include "object_utils.h" 31c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes#include "stl_util.h" 325f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#include "thread.h" 338e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes#include "thread_list.h" 345f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 355f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesnamespace art { 365f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 385f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Every Object has a monitor associated with it, but not every Object is 395f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * actually locked. Even the ones that are locked do not need a 405f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * full-fledged monitor until a) there is actual contention or b) wait() 415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * is called on the Object. 425f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 435f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * For Android, we have implemented a scheme similar to the one described 445f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * in Bacon et al.'s "Thin locks: featherweight synchronization for Java" 455f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * (ACM 1998). Things are even easier for us, though, because we have 465f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * a full 32 bits to work with. 475f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 485f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The two states of an Object's lock are referred to as "thin" and 495f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * "fat". A lock may transition from the "thin" state to the "fat" 505f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * state and this transition is referred to as inflation. Once a lock 515f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * has been inflated it remains in the "fat" state indefinitely. 525f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 535f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The lock value itself is stored in Object.lock. The LSB of the 545f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * lock encodes its state. When cleared, the lock is in the "thin" 555f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * state and its bits are formatted as follows: 565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * [31 ---- 19] [18 ---- 3] [2 ---- 1] [0] 585f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * lock count thread id hash state 0 595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * When set, the lock is in the "fat" state and its bits are formatted 615f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * as follows: 625f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 635f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * [31 ---- 3] [2 ---- 1] [0] 645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * pointer hash state 1 655f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 665f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * For an in-depth description of the mechanics of thin-vs-fat locking, 675f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * read the paper referred to above. 6854e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes * 695f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Monitors provide: 705f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - mutually exclusive access to resources 715f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - a way for multiple threads to wait for notification 725f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 735f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * In effect, they fill the role of both mutexes and condition variables. 745f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 755f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Only one thread can own the monitor at any time. There may be several 765f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * threads waiting on it (the wait call unlocks it). One or more waiting 775f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * threads may be getting interrupted or notified at any given time. 785f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * TODO: the various members of monitor are not SMP-safe. 805f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 8154e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes 8254e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes 8354e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes/* 8454e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes * Monitor accessor. Extracts a monitor structure pointer from a fat 8554e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes * lock. Performs no error checking. 8654e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes */ 8754e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes#define LW_MONITOR(x) \ 8854e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes ((Monitor*)((x) & ~((LW_HASH_STATE_MASK << LW_HASH_STATE_SHIFT) | LW_SHAPE_MASK))) 8954e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes 9054e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes/* 9154e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes * Lock recursion count field. Contains a count of the number of times 9254e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes * a lock has been recursively acquired. 9354e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes */ 9454e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes#define LW_LOCK_COUNT_MASK 0x1fff 9554e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes#define LW_LOCK_COUNT_SHIFT 19 9654e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes#define LW_LOCK_COUNT(x) (((x) >> LW_LOCK_COUNT_SHIFT) & LW_LOCK_COUNT_MASK) 9754e7df1896a4066cbb9fe6f72249829f0b8c49c6Elliott Hughes 98fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughesbool (*Monitor::is_sensitive_thread_hook_)() = NULL; 99fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughesuint32_t Monitor::lock_profiling_threshold_ = 0; 10032d6e1e5654433d7eadede89e1c770b2c839aee9Elliott Hughes 101fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughesbool Monitor::IsSensitiveThread() { 102fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes if (is_sensitive_thread_hook_ != NULL) { 103fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes return (*is_sensitive_thread_hook_)(); 104fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 105fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes return false; 106fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes} 107fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes 1084dd9b4d95eec9db5338fb9bf132f9bb8facf6cf4Elliott Hughesvoid Monitor::Init(uint32_t lock_profiling_threshold, bool (*is_sensitive_thread_hook)()) { 109fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes lock_profiling_threshold_ = lock_profiling_threshold; 110fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes is_sensitive_thread_hook_ = is_sensitive_thread_hook; 11132d6e1e5654433d7eadede89e1c770b2c839aee9Elliott Hughes} 11232d6e1e5654433d7eadede89e1c770b2c839aee9Elliott Hughes 1135f79133a435ebcb20000370d56046fe01201dd80Elliott HughesMonitor::Monitor(Object* obj) 1145f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes : owner_(NULL), 1155f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes lock_count_(0), 1165f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes obj_(obj), 1175f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wait_set_(NULL), 1185f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes lock_("a monitor lock"), 11933dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_method_(NULL), 12033dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_pc_(0) { 1215f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 1225f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1235f79133a435ebcb20000370d56046fe01201dd80Elliott HughesMonitor::~Monitor() { 1245f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(obj_ != NULL); 1255f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK_EQ(LW_SHAPE(*obj_->GetRawLockWordAddress()), LW_SHAPE_FAT); 1265f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 1275f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1285f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 1295f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Links a thread into a monitor's wait set. The monitor lock must be 1305f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * held by the caller of this routine. 1315f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 1325f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::AppendToWaitSet(Thread* thread) { 1335f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(owner_ == Thread::Current()); 1345f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(thread != NULL); 135dc33ad5db2dc6ed9b76d5219888626a604debbe1Elliott Hughes DCHECK(thread->wait_next_ == NULL) << thread->wait_next_; 1365f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (wait_set_ == NULL) { 1375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wait_set_ = thread; 1385f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 1395f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 1405f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // push_back. 1425f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* t = wait_set_; 1435f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes while (t->wait_next_ != NULL) { 1445f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes t = t->wait_next_; 1455f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 1465f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes t->wait_next_ = thread; 1475f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 1485f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1495f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 1505f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Unlinks a thread from a monitor's wait set. The monitor lock must 1515f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * be held by the caller of this routine. 1525f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 1535f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::RemoveFromWaitSet(Thread *thread) { 1545f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(owner_ == Thread::Current()); 1555f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(thread != NULL); 1565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (wait_set_ == NULL) { 1575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 1585f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 1595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (wait_set_ == thread) { 1605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wait_set_ = thread->wait_next_; 1615f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thread->wait_next_ = NULL; 1625f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 1635f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 1645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1655f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* t = wait_set_; 1665f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes while (t->wait_next_ != NULL) { 1675f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (t->wait_next_ == thread) { 1685f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes t->wait_next_ = thread->wait_next_; 1695f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thread->wait_next_ = NULL; 1705f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 1715f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 1725f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes t = t->wait_next_; 1735f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 1745f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 1755f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 176c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott HughesObject* Monitor::GetObject() { 177c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes return obj_; 1785f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 1795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1805f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::Lock(Thread* self) { 1815f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (owner_ == self) { 1825f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes lock_count_++; 1835f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 1845f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 185fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes 186fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes uint64_t waitStart, waitEnd; 1875f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (!lock_.TryLock()) { 188fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes uint32_t wait_threshold = lock_profiling_threshold_; 18933dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao const Method* current_locking_method = NULL; 190e65a6c99b0fd8908484b61c3c8f5a43cf0081f3cElliott Hughes uintptr_t current_locking_pc = 0; 1915f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes { 1925f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes ScopedThreadStateChange tsc(self, Thread::kBlocked); 193fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes if (wait_threshold != 0) { 194fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes waitStart = NanoTime() / 1000; 195fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 19633dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao current_locking_method = locking_method_; 19733dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao current_locking_pc = locking_pc_; 1985f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 1995f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes lock_.Lock(); 200fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes if (wait_threshold != 0) { 201fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes waitEnd = NanoTime() / 1000; 202fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 203fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 204fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes 205fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes if (wait_threshold != 0) { 206fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes uint64_t wait_ms = (waitEnd - waitStart) / 1000; 207fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes uint32_t sample_percent; 208fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes if (wait_ms >= wait_threshold) { 209fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes sample_percent = 100; 210fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } else { 211fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes sample_percent = 100 * wait_ms / wait_threshold; 212fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 213fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes if (sample_percent != 0 && (static_cast<uint32_t>(rand() % 100) < sample_percent)) { 21433dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao const char* current_locking_filename; 21533dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao uint32_t current_locking_line_number; 21633dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao TranslateLocation(current_locking_method, current_locking_pc, 21733dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao current_locking_filename, current_locking_line_number); 21833dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao LogContentionEvent(self, wait_ms, sample_percent, current_locking_filename, current_locking_line_number); 219fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 2205f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 2215f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 2225f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes owner_ = self; 2235f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK_EQ(lock_count_, 0); 2245f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 2255f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // When debugging, save the current monitor holder for future 2265f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // acquisition failures to use in sampled logging. 227fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes if (lock_profiling_threshold_ != 0) { 228d07986fad0d08cdf05505cf9230714a2cf0dd9aeElliott Hughes locking_method_ = self->GetCurrentMethod(&locking_pc_); 229fc86162ce2a3467acb690e18cc8bd9b3daafc606Elliott Hughes } 2305f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 2315f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 2326d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogersstatic void ThrowIllegalMonitorStateExceptionF(const char* fmt, ...) 2336d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers __attribute__((format(printf, 1, 2))); 2346d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers 2356d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogersstatic void ThrowIllegalMonitorStateExceptionF(const char* fmt, ...) { 2366d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers va_list args; 2376d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers va_start(args, fmt); 2386d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers Thread::Current()->ThrowNewExceptionV("Ljava/lang/IllegalMonitorStateException;", fmt, args); 2396d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers va_end(args); 2406d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers} 2416d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers 242d423741f91526cada9d081c64ee295ec9863032dElliott Hughesstatic std::string ThreadToString(Thread* thread) { 243d423741f91526cada9d081c64ee295ec9863032dElliott Hughes if (thread == NULL) { 244d423741f91526cada9d081c64ee295ec9863032dElliott Hughes return "NULL"; 245d423741f91526cada9d081c64ee295ec9863032dElliott Hughes } 246d423741f91526cada9d081c64ee295ec9863032dElliott Hughes std::ostringstream oss; 247d423741f91526cada9d081c64ee295ec9863032dElliott Hughes // TODO: alternatively, we could just return the thread's name. 248d423741f91526cada9d081c64ee295ec9863032dElliott Hughes oss << *thread; 249d423741f91526cada9d081c64ee295ec9863032dElliott Hughes return oss.str(); 250d423741f91526cada9d081c64ee295ec9863032dElliott Hughes} 251d423741f91526cada9d081c64ee295ec9863032dElliott Hughes 2526d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogersvoid Monitor::FailedUnlock(Object* obj, Thread* expected_owner, Thread* found_owner, 2536d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers Monitor* mon) { 2546d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers // Acquire thread list lock so threads won't disappear from under us 2556d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ScopedThreadListLock tll; 2566d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers // Re-read owner now that we hold lock 2576d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers Thread* current_owner = mon != NULL ? mon->owner_ : NULL; 2586d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (current_owner == NULL) { 2596d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (found_owner == NULL) { 2606d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of unowned monitor on object of type '%s'" 2616d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " on thread '%s'", 262d423741f91526cada9d081c64ee295ec9863032dElliott Hughes PrettyTypeOf(obj).c_str(), 263d423741f91526cada9d081c64ee295ec9863032dElliott Hughes ThreadToString(expected_owner).c_str()); 2646d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 2656d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers // Race: the original read found an owner but now there is none 2666d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor owned by '%s' on object of type '%s'" 2676d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " (where now the monitor appears unowned) on thread '%s'", 268d423741f91526cada9d081c64ee295ec9863032dElliott Hughes ThreadToString(found_owner).c_str(), 269d423741f91526cada9d081c64ee295ec9863032dElliott Hughes PrettyTypeOf(obj).c_str(), 270d423741f91526cada9d081c64ee295ec9863032dElliott Hughes ThreadToString(expected_owner).c_str()); 2716d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 2726d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 2736d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (found_owner == NULL) { 2746d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers // Race: originally there was no owner, there is now 2756d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor owned by '%s' on object of type '%s'" 2766d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " (originally believed to be unowned) on thread '%s'", 277d423741f91526cada9d081c64ee295ec9863032dElliott Hughes ThreadToString(current_owner).c_str(), 278d423741f91526cada9d081c64ee295ec9863032dElliott Hughes PrettyTypeOf(obj).c_str(), 279d423741f91526cada9d081c64ee295ec9863032dElliott Hughes ThreadToString(expected_owner).c_str()); 2806d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 2816d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (found_owner != current_owner) { 2826d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers // Race: originally found and current owner have changed 2836d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor originally owned by '%s' (now" 2846d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " owned by '%s') on object of type '%s' on thread '%s'", 285d423741f91526cada9d081c64ee295ec9863032dElliott Hughes ThreadToString(found_owner).c_str(), 286d423741f91526cada9d081c64ee295ec9863032dElliott Hughes ThreadToString(current_owner).c_str(), 287d423741f91526cada9d081c64ee295ec9863032dElliott Hughes PrettyTypeOf(obj).c_str(), 288d423741f91526cada9d081c64ee295ec9863032dElliott Hughes ThreadToString(expected_owner).c_str()); 2896d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } else { 2906d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("unlock of monitor owned by '%s' on object of type '%s'" 2916d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers " on thread '%s", 292d423741f91526cada9d081c64ee295ec9863032dElliott Hughes ThreadToString(current_owner).c_str(), 293d423741f91526cada9d081c64ee295ec9863032dElliott Hughes PrettyTypeOf(obj).c_str(), 294d423741f91526cada9d081c64ee295ec9863032dElliott Hughes ThreadToString(expected_owner).c_str()); 2956d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 2966d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 2976d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers } 2985f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 2995f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 3005f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesbool Monitor::Unlock(Thread* self) { 3015f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 3026d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers Thread* owner = owner_; 3036d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers if (owner == self) { 3045f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // We own the monitor, so nobody else can be in here. 3055f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (lock_count_ == 0) { 3065f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes owner_ = NULL; 30733dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_method_ = NULL; 30833dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_pc_ = 0; 3095f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes lock_.Unlock(); 3105f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 3115f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes --lock_count_; 3125f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 3135f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 3145f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // We don't own this, so we're not allowed to unlock it. 3155f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // The JNI spec says that we should throw IllegalMonitorStateException 3165f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // in this case. 3176d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers FailedUnlock(obj_, self, owner, this); 3185f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return false; 3195f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 3205f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return true; 3215f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 3225f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 3235f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 3245f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Converts the given relative waiting time into an absolute time. 3255f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 3265f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid ToAbsoluteTime(int64_t ms, int32_t ns, struct timespec *ts) { 3275f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes int64_t endSec; 3285f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 3295f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#ifdef HAVE_TIMEDWAIT_MONOTONIC 3305f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes clock_gettime(CLOCK_MONOTONIC, ts); 3315f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#else 3325f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes { 3335f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes struct timeval tv; 3345f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes gettimeofday(&tv, NULL); 3355f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes ts->tv_sec = tv.tv_sec; 3365f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes ts->tv_nsec = tv.tv_usec * 1000; 3375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 3385f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#endif 3395f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes endSec = ts->tv_sec + ms / 1000; 3405f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (endSec >= 0x7fffffff) { 3415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes LOG(INFO) << "Note: end time exceeds epoch"; 3425f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes endSec = 0x7ffffffe; 3435f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 3445f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes ts->tv_sec = endSec; 3455f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes ts->tv_nsec = (ts->tv_nsec + (ms % 1000) * 1000000) + ns; 3465f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 3475f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Catch rollover. 3485f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (ts->tv_nsec >= 1000000000L) { 3495f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes ts->tv_sec++; 3505f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes ts->tv_nsec -= 1000000000L; 3515f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 3525f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 3535f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 3545f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesint dvmRelativeCondWait(pthread_cond_t* cond, pthread_mutex_t* mutex, int64_t ms, int32_t ns) { 3555f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes struct timespec ts; 3565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes ToAbsoluteTime(ms, ns, &ts); 3575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#if defined(HAVE_TIMEDWAIT_MONOTONIC) 3585f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes int rc = pthread_cond_timedwait_monotonic(cond, mutex, &ts); 3595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#else 3605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes int rc = pthread_cond_timedwait(cond, mutex, &ts); 3615f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes#endif 3625f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(rc == 0 || rc == ETIMEDOUT); 3635f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return rc; 3645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 3655f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 3665f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 3675f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Wait on a monitor until timeout, interrupt, or notification. Used for 3685f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Object.wait() and (somewhat indirectly) Thread.sleep() and Thread.join(). 3695f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 3705f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * If another thread calls Thread.interrupt(), we throw InterruptedException 3715f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * and return immediately if one of the following are true: 3725f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - blocked in wait(), wait(long), or wait(long, int) methods of Object 3735f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - blocked in join(), join(long), or join(long, int) methods of Thread 3745f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * - blocked in sleep(long), or sleep(long, int) methods of Thread 3755f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Otherwise, we set the "interrupted" flag. 3765f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 3775f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Checks to make sure that "ns" is in the range 0-999999 3785f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * (i.e. fractions of a millisecond) and throws the appropriate 3795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * exception if it isn't. 3805f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 3815f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The spec allows "spurious wakeups", and recommends that all code using 3825f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Object.wait() do so in a loop. This appears to derive from concerns 3835f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * about pthread_cond_wait() on multiprocessor systems. Some commentary 3845f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * on the web casts doubt on whether these can/should occur. 3855f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 3865f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Since we're allowed to wake up "early", we clamp extremely long durations 3875f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * to return at the end of the 32-bit time epoch. 3885f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 3895f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::Wait(Thread* self, int64_t ms, int32_t ns, bool interruptShouldThrow) { 3905f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 3915f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 3925f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Make sure that we hold the lock. 3935f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (owner_ != self) { 3946d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before wait()"); 3955f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 3965f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 3975f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 3985f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Enforce the timeout range. 3995f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (ms < 0 || ns < 0 || ns > 999999) { 4005cb5ad27944efb08d4556b3c0d362302e37e832bElliott Hughes Thread::Current()->ThrowNewExceptionF("Ljava/lang/IllegalArgumentException;", 4015f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes "timeout arguments out of range: ms=%lld ns=%d", ms, ns); 4025f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 4035f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 4045f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4055f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Compute absolute wakeup time, if necessary. 4065f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes struct timespec ts; 4075f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes bool timed = false; 4085f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (ms != 0 || ns != 0) { 4095f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes ToAbsoluteTime(ms, ns, &ts); 4105f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes timed = true; 4115f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 4125f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4135f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 4145f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Add ourselves to the set of threads waiting on this monitor, and 4155f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * release our hold. We need to let it go even if we're a few levels 4165f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * deep in a recursive lock, and we need to restore that later. 4175f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 4185f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * We append to the wait set ahead of clearing the count and owner 4195f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * fields so the subroutine can check that the calling thread owns 4205f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * the monitor. Aside from that, the order of member updates is 4215f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * not order sensitive as we hold the pthread mutex. 4225f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 4235f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes AppendToWaitSet(self); 4245f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes int prevLockCount = lock_count_; 4255f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes lock_count_ = 0; 4265f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes owner_ = NULL; 42733dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao const Method* savedMethod = locking_method_; 42833dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_method_ = NULL; 429e65a6c99b0fd8908484b61c3c8f5a43cf0081f3cElliott Hughes uintptr_t savedPc = locking_pc_; 43033dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_pc_ = 0; 4315f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4325f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 4335f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Update thread status. If the GC wakes up, it'll ignore us, knowing 4345f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * that we won't touch any references in this state, and we'll check 4355f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * our suspend mode before we transition out. 4365f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 4375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (timed) { 4385f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes self->SetState(Thread::kTimedWaiting); 4395f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 4405f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes self->SetState(Thread::kWaiting); 4415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 4425f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 44385d1545e985ac689db4bad7849880e843707c862Elliott Hughes self->wait_mutex_->Lock(); 4445f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4455f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 4465f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Set wait_monitor_ to the monitor object we will be waiting on. 4475f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * When wait_monitor_ is non-NULL a notifying or interrupting thread 4485f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * must signal the thread's wait_cond_ to wake it up. 4495f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 4505f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self->wait_monitor_ == NULL); 4515f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes self->wait_monitor_ = this; 4525f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4535f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 4545f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Handle the case where the thread was interrupted before we called 4555f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * wait(). 4565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 4575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes bool wasInterrupted = false; 4585f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (self->interrupted_) { 4595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wasInterrupted = true; 4605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes self->wait_monitor_ = NULL; 46185d1545e985ac689db4bad7849880e843707c862Elliott Hughes self->wait_mutex_->Unlock(); 4625f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes goto done; 4635f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 4645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4655f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 4665f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Release the monitor lock and wait for a notification or 4675f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * a timeout to occur. 4685f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 4695f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes lock_.Unlock(); 4705f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4715f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (!timed) { 47285d1545e985ac689db4bad7849880e843707c862Elliott Hughes self->wait_cond_->Wait(*self->wait_mutex_); 4735f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 47485d1545e985ac689db4bad7849880e843707c862Elliott Hughes self->wait_cond_->TimedWait(*self->wait_mutex_, ts); 4755f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 4765f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (self->interrupted_) { 4775f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wasInterrupted = true; 4785f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 4795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4805f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes self->interrupted_ = false; 4815f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes self->wait_monitor_ = NULL; 48285d1545e985ac689db4bad7849880e843707c862Elliott Hughes self->wait_mutex_->Unlock(); 4835f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4845f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Reacquire the monitor lock. 4855f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Lock(self); 4865f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 4875f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesdone: 4885f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 4895f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * We remove our thread from wait set after restoring the count 4905f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * and owner fields so the subroutine can check that the calling 4915f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * thread owns the monitor. Aside from that, the order of member 4925f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * updates is not order sensitive as we hold the pthread mutex. 4935f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 4945f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes owner_ = self; 4955f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes lock_count_ = prevLockCount; 49633dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_method_ = savedMethod; 49733dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao locking_pc_ = savedPc; 4985f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes RemoveFromWaitSet(self); 4995f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5005f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* set self->status back to Thread::kRunnable, and self-suspend if needed */ 5015f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes self->SetState(Thread::kRunnable); 5025f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5035f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (wasInterrupted) { 5045f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 5055f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * We were interrupted while waiting, or somebody interrupted an 5065f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * un-interruptible thread earlier and we're bailing out immediately. 5075f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * 5085f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The doc sayeth: "The interrupted status of the current thread is 5095f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * cleared when this exception is thrown." 5105f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 5115f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes self->interrupted_ = false; 5125f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (interruptShouldThrow) { 5135cb5ad27944efb08d4556b3c0d362302e37e832bElliott Hughes Thread::Current()->ThrowNewException("Ljava/lang/InterruptedException;", NULL); 5145f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5155f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5165f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 5175f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5185f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::Notify(Thread* self) { 5195f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 5205f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5215f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Make sure that we hold the lock. 5225f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (owner_ != self) { 5236d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notify()"); 5245f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 5255f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5265f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Signal the first waiting thread in the wait set. 5275f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes while (wait_set_ != NULL) { 5285f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* thread = wait_set_; 5295f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wait_set_ = thread->wait_next_; 5305f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thread->wait_next_ = NULL; 5315f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5325f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Check to see if the thread is still waiting. 53385d1545e985ac689db4bad7849880e843707c862Elliott Hughes MutexLock mu(*thread->wait_mutex_); 5345f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (thread->wait_monitor_ != NULL) { 53585d1545e985ac689db4bad7849880e843707c862Elliott Hughes thread->wait_cond_->Signal(); 5365f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 5375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5385f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5395f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 5405f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::NotifyAll(Thread* self) { 5425f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 5435f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5445f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Make sure that we hold the lock. 5455f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (owner_ != self) { 5466d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notifyAll()"); 5475f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 5485f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5495f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Signal all threads in the wait set. 5505f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes while (wait_set_ != NULL) { 5515f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* thread = wait_set_; 5525f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes wait_set_ = thread->wait_next_; 5535f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thread->wait_next_ = NULL; 5545f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thread->Notify(); 5555f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 5565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 5575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5585f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 5595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Changes the shape of a monitor from thin to fat, preserving the 5605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * internal lock state. The calling thread must own the lock. 5615f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 5625f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::Inflate(Thread* self, Object* obj) { 5635f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 5645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(obj != NULL); 5655f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK_EQ(LW_SHAPE(*obj->GetRawLockWordAddress()), LW_SHAPE_THIN); 566f8e012785ee61a3d2f43f74a249d66e1381bdb83Elliott Hughes DCHECK_EQ(LW_LOCK_OWNER(*obj->GetRawLockWordAddress()), static_cast<int32_t>(self->GetThinLockId())); 5675f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5685f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Allocate and acquire a new monitor. 5695f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Monitor* m = new Monitor(obj); 5704dd9b4d95eec9db5338fb9bf132f9bb8facf6cf4Elliott Hughes VLOG(monitor) << "monitor: thread " << self->GetThinLockId() 5714dd9b4d95eec9db5338fb9bf132f9bb8facf6cf4Elliott Hughes << " created monitor " << m << " for object " << obj; 572c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes Runtime::Current()->GetMonitorList()->Add(m); 5735f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes m->Lock(self); 5745f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Propagate the lock state. 5755f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes uint32_t thin = *obj->GetRawLockWordAddress(); 5765f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes m->lock_count_ = LW_LOCK_COUNT(thin); 5775f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thin &= LW_HASH_STATE_MASK << LW_HASH_STATE_SHIFT; 5785f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thin |= reinterpret_cast<uint32_t>(m) | LW_SHAPE_FAT; 5795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Publish the updated lock word. 5805f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes android_atomic_release_store(thin, obj->GetRawLockWordAddress()); 5815f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 5825f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5835f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::MonitorEnter(Thread* self, Object* obj) { 5845f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes volatile int32_t* thinp = obj->GetRawLockWordAddress(); 5855f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes struct timespec tm; 5865f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes long sleepDelayNs; 5875f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes long minSleepDelayNs = 1000000; /* 1 millisecond */ 5885f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes long maxSleepDelayNs = 1000000000; /* 1 second */ 589f8e012785ee61a3d2f43f74a249d66e1381bdb83Elliott Hughes uint32_t thin, newThin; 5905f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 5914681c809ba35d50fab92c592ce8d2c7f8b2731f7Elliott Hughes DCHECK(self != NULL); 5924681c809ba35d50fab92c592ce8d2c7f8b2731f7Elliott Hughes DCHECK(obj != NULL); 593f8e012785ee61a3d2f43f74a249d66e1381bdb83Elliott Hughes uint32_t threadId = self->GetThinLockId(); 5945f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesretry: 5955f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thin = *thinp; 5965f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (LW_SHAPE(thin) == LW_SHAPE_THIN) { 5975f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 5985f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The lock is a thin lock. The owner field is used to 5995f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * determine the acquire method, ordered by cost. 6005f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 6015f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (LW_LOCK_OWNER(thin) == threadId) { 6025f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 6035f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The calling thread owns the lock. Increment the 6045f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * value of the recursion count field. 6055f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 6065f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes *thinp += 1 << LW_LOCK_COUNT_SHIFT; 6075f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (LW_LOCK_COUNT(*thinp) == LW_LOCK_COUNT_MASK) { 6085f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 6095f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The reacquisition limit has been reached. Inflate 6105f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * the lock so the next acquire will not overflow the 6115f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * recursion count field. 6125f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 6135f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Inflate(self, obj); 6145f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6155f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else if (LW_LOCK_OWNER(thin) == 0) { 6165f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 6175f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The lock is unowned. Install the thread id of the 6185f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * calling thread into the owner field. This is the 6195f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * common case. In performance critical code the JIT 6205f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * will have tried this before calling out to the VM. 6215f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 6225f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes newThin = thin | (threadId << LW_LOCK_OWNER_SHIFT); 6235f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (android_atomic_acquire_cas(thin, newThin, thinp) != 0) { 6245f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // The acquire failed. Try again. 6255f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes goto retry; 6265f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6275f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 6284dd9b4d95eec9db5338fb9bf132f9bb8facf6cf4Elliott Hughes VLOG(monitor) << StringPrintf("monitor: thread %d spin on lock %p (a %s) owned by %d", 6294dd9b4d95eec9db5338fb9bf132f9bb8facf6cf4Elliott Hughes threadId, thinp, PrettyTypeOf(obj).c_str(), LW_LOCK_OWNER(thin)); 6305f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // The lock is owned by another thread. Notify the VM that we are about to wait. 6318e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes self->monitor_enter_object_ = obj; 6325f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread::State oldStatus = self->SetState(Thread::kBlocked); 6335f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Spin until the thin lock is released or inflated. 6345f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes sleepDelayNs = 0; 6355f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes for (;;) { 6365f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thin = *thinp; 6375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Check the shape of the lock word. Another thread 6385f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // may have inflated the lock while we were waiting. 6395f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (LW_SHAPE(thin) == LW_SHAPE_THIN) { 6405f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (LW_LOCK_OWNER(thin) == 0) { 6415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // The lock has been released. Install the thread id of the 6425f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // calling thread into the owner field. 6435f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes newThin = thin | (threadId << LW_LOCK_OWNER_SHIFT); 6445f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (android_atomic_acquire_cas(thin, newThin, thinp) == 0) { 6455f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // The acquire succeed. Break out of the loop and proceed to inflate the lock. 6465f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes break; 6475f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6485f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 6495f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // The lock has not been released. Yield so the owning thread can run. 6505f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (sleepDelayNs == 0) { 6515f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes sched_yield(); 6525f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes sleepDelayNs = minSleepDelayNs; 6535f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 6545f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes tm.tv_sec = 0; 6555f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes tm.tv_nsec = sleepDelayNs; 6565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes nanosleep(&tm, NULL); 6575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Prepare the next delay value. Wrap to avoid once a second polls for eternity. 6585f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (sleepDelayNs < maxSleepDelayNs / 2) { 6595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes sleepDelayNs *= 2; 6605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 6615f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes sleepDelayNs = minSleepDelayNs; 6625f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6635f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6655f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 6665f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // The thin lock was inflated by another thread. Let the VM know we are no longer 6675f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // waiting and try again. 6684dd9b4d95eec9db5338fb9bf132f9bb8facf6cf4Elliott Hughes VLOG(monitor) << "monitor: thread " << threadId 6694dd9b4d95eec9db5338fb9bf132f9bb8facf6cf4Elliott Hughes << " found lock " << (void*) thinp << " surprise-fattened by another thread"; 6708e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes self->monitor_enter_object_ = NULL; 6715f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes self->SetState(oldStatus); 6725f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes goto retry; 6735f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6745f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6754dd9b4d95eec9db5338fb9bf132f9bb8facf6cf4Elliott Hughes VLOG(monitor) << StringPrintf("monitor: thread %d spin on lock %p done", threadId, thinp); 6765f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // We have acquired the thin lock. Let the VM know that we are no longer waiting. 6778e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes self->monitor_enter_object_ = NULL; 6785f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes self->SetState(oldStatus); 6795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Fatten the lock. 6805f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Inflate(self, obj); 6814dd9b4d95eec9db5338fb9bf132f9bb8facf6cf4Elliott Hughes VLOG(monitor) << StringPrintf("monitor: thread %d fattened lock %p", threadId, thinp); 6825f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6835f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 6845f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // The lock is a fat lock. 6854dd9b4d95eec9db5338fb9bf132f9bb8facf6cf4Elliott Hughes VLOG(monitor) << StringPrintf("monitor: thread %d locking fat lock %p (%p) %p on a %s", 686f8e012785ee61a3d2f43f74a249d66e1381bdb83Elliott Hughes threadId, thinp, LW_MONITOR(*thinp), (void*)*thinp, PrettyTypeOf(obj).c_str()); 6875f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(LW_MONITOR(*thinp) != NULL); 6885f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes LW_MONITOR(*thinp)->Lock(self); 6895f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 6905f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 6915f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 6925f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesbool Monitor::MonitorExit(Thread* self, Object* obj) { 6935f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes volatile int32_t* thinp = obj->GetRawLockWordAddress(); 6945f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 6955f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(self != NULL); 6964681c809ba35d50fab92c592ce8d2c7f8b2731f7Elliott Hughes //DCHECK_EQ(self->GetState(), Thread::kRunnable); 6975f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(obj != NULL); 6985f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 6995f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 7005f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Cache the lock word as its value can change while we are 7015f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * examining its state. 7025f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 7035f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes uint32_t thin = *thinp; 7045f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (LW_SHAPE(thin) == LW_SHAPE_THIN) { 7055f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 7065f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The lock is thin. We must ensure that the lock is owned 7075f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * by the given thread before unlocking it. 7085f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 709f8e012785ee61a3d2f43f74a249d66e1381bdb83Elliott Hughes if (LW_LOCK_OWNER(thin) == self->GetThinLockId()) { 7105f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 7115f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * We are the lock owner. It is safe to update the lock 7125f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * without CAS as lock ownership guards the lock itself. 7135f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 7145f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (LW_LOCK_COUNT(thin) == 0) { 7155f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 7165f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The lock was not recursively acquired, the common 7175f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * case. Unlock by clearing all bits except for the 7185f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * hash state. 7195f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 7205f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes thin &= (LW_HASH_STATE_MASK << LW_HASH_STATE_SHIFT); 7215f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes android_atomic_release_store(thin, thinp); 7225f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 7235f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 7245f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The object was recursively acquired. Decrement the 7255f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * lock recursion count field. 7265f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 7275f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes *thinp -= 1 << LW_LOCK_COUNT_SHIFT; 7285f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7295f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 7305f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 7315f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * We do not own the lock. The JVM spec requires that we 7325f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * throw an exception in this case. 7335f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 7346d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers FailedUnlock(obj, self, NULL, NULL); 7355f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return false; 7365f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7375f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 7385f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* 7395f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * The lock is fat. We must check to see if Unlock has 7405f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * raised any exceptions before continuing. 7415f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 7425f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes DCHECK(LW_MONITOR(*thinp) != NULL); 7435f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (!LW_MONITOR(*thinp)->Unlock(self)) { 7445f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // An exception has been raised. Do not fall through. 7455f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return false; 7465f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7475f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7485f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return true; 7495f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 7505f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 7515f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes/* 7525f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * Object.wait(). Also called for class init. 7535f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 7545f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::Wait(Thread* self, Object *obj, int64_t ms, int32_t ns, bool interruptShouldThrow) { 7555f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes volatile int32_t* thinp = obj->GetRawLockWordAddress(); 7565f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 7575f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // If the lock is still thin, we need to fatten it. 7585f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes uint32_t thin = *thinp; 7595f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (LW_SHAPE(thin) == LW_SHAPE_THIN) { 7605f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Make sure that 'self' holds the lock. 761f8e012785ee61a3d2f43f74a249d66e1381bdb83Elliott Hughes if (LW_LOCK_OWNER(thin) != self->GetThinLockId()) { 7626d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before wait()"); 7635f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 7645f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7655f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 7665f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes /* This thread holds the lock. We need to fatten the lock 7675f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * so 'self' can block on it. Don't update the object lock 7685f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * field yet, because 'self' needs to acquire the lock before 7695f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes * any other thread gets a chance. 7705f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes */ 7715f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Inflate(self, obj); 7724dd9b4d95eec9db5338fb9bf132f9bb8facf6cf4Elliott Hughes VLOG(monitor) << StringPrintf("monitor: thread %d fattened lock %p by wait()", self->GetThinLockId(), thinp); 7735f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7745f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes LW_MONITOR(*thinp)->Wait(self, ms, ns, interruptShouldThrow); 7755f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 7765f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 7775f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::Notify(Thread* self, Object *obj) { 7785f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes uint32_t thin = *obj->GetRawLockWordAddress(); 7795f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 7805f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // If the lock is still thin, there aren't any waiters; 7815f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // waiting on an object forces lock fattening. 7825f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (LW_SHAPE(thin) == LW_SHAPE_THIN) { 7835f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Make sure that 'self' holds the lock. 784f8e012785ee61a3d2f43f74a249d66e1381bdb83Elliott Hughes if (LW_LOCK_OWNER(thin) != self->GetThinLockId()) { 7856d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notify()"); 7865f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 7875f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7885f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // no-op; there are no waiters to notify. 7895f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 7905f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // It's a fat lock. 7915f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes LW_MONITOR(thin)->Notify(self); 7925f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 7935f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 7945f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 7955f79133a435ebcb20000370d56046fe01201dd80Elliott Hughesvoid Monitor::NotifyAll(Thread* self, Object *obj) { 7965f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes uint32_t thin = *obj->GetRawLockWordAddress(); 7975f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 7985f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // If the lock is still thin, there aren't any waiters; 7995f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // waiting on an object forces lock fattening. 8005f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (LW_SHAPE(thin) == LW_SHAPE_THIN) { 8015f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // Make sure that 'self' holds the lock. 802f8e012785ee61a3d2f43f74a249d66e1381bdb83Elliott Hughes if (LW_LOCK_OWNER(thin) != self->GetThinLockId()) { 8036d0b13e931fb73d5e964d14b0a7ecd1f3f5db547Ian Rogers ThrowIllegalMonitorStateExceptionF("object not locked by thread before notifyAll()"); 8045f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return; 8055f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 8065f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // no-op; there are no waiters to notify. 8075f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 8085f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes // It's a fat lock. 8095f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes LW_MONITOR(thin)->NotifyAll(self); 8105f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 8115f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 8125f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 81324a3c2e9924e8765c4a9b4d383cb8f3b922f9c9fBrian Carlstromuint32_t Monitor::GetThinLockId(uint32_t raw_lock_word) { 8145f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes if (LW_SHAPE(raw_lock_word) == LW_SHAPE_THIN) { 8155f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return LW_LOCK_OWNER(raw_lock_word); 8165f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } else { 8175f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes Thread* owner = LW_MONITOR(raw_lock_word)->owner_; 8185f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes return owner ? owner->GetThinLockId() : 0; 8195f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes } 8205f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} 8215f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes 8228e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughesvoid Monitor::DescribeWait(std::ostream& os, const Thread* thread) { 8238e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes Thread::State state = thread->GetState(); 8248e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes 8258e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes Object* object = NULL; 8268e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes uint32_t lock_owner = ThreadList::kInvalidId; 8278e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes if (state == Thread::kWaiting || state == Thread::kTimedWaiting) { 8288e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes os << " - waiting on "; 8298e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes Monitor* monitor = thread->wait_monitor_; 8308e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes if (monitor != NULL) { 8318e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes object = monitor->obj_; 8328e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 8338e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes lock_owner = Thread::LockOwnerFromThreadLock(object); 8348e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } else if (state == Thread::kBlocked) { 8358e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes os << " - waiting to lock "; 8368e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes object = thread->monitor_enter_object_; 8378e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes if (object != NULL) { 83824a3c2e9924e8765c4a9b4d383cb8f3b922f9c9fBrian Carlstrom lock_owner = object->GetThinLockId(); 8398e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 8408e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } else { 8418e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes // We're not waiting on anything. 8428e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes return; 8438e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 8448e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes os << "<" << object << ">"; 8458e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes 8468e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes // - waiting on <0x613f83d8> (a java.lang.ThreadLock) held by thread 5 8478e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes // - waiting on <0x6008c468> (a java.lang.Class<java.lang.ref.ReferenceQueue>) 8488e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes os << " (a " << PrettyTypeOf(object) << ")"; 8498e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes 8508e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes if (lock_owner != ThreadList::kInvalidId) { 8518e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes os << " held by thread " << lock_owner; 8528e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes } 8538e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes 8548e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes os << "\n"; 8558e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes} 8568e4aac52962d54cb4be2078b9cd95685e067133aElliott Hughes 85733dc7717cd16592bcc825350bea6305be9eb2ea1jeffhaovoid Monitor::TranslateLocation(const Method* method, uint32_t pc, 85833dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao const char*& source_file, uint32_t& line_number) const { 85933dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao // If method is null, location is unknown 86033dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao if (method == NULL) { 86112c51e3e5a8b5655351539618f1cf2331f52d1abElliott Hughes source_file = ""; 86233dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao line_number = 0; 86333dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao return; 86433dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao } 8656d4d9fcb4f01e287ee29e81cd1c941ee5d11d379Ian Rogers MethodHelper mh(method); 8666d4d9fcb4f01e287ee29e81cd1c941ee5d11d379Ian Rogers source_file = mh.GetDeclaringClassSourceFile(); 86712c51e3e5a8b5655351539618f1cf2331f52d1abElliott Hughes if (source_file == NULL) { 86812c51e3e5a8b5655351539618f1cf2331f52d1abElliott Hughes source_file = ""; 86912c51e3e5a8b5655351539618f1cf2331f52d1abElliott Hughes } 8706d4d9fcb4f01e287ee29e81cd1c941ee5d11d379Ian Rogers line_number = mh.GetLineNumFromNativePC(pc); 87133dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao} 87233dc7717cd16592bcc825350bea6305be9eb2ea1jeffhao 873c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott HughesMonitorList::MonitorList() : lock_("MonitorList lock") { 874c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 875c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 876c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott HughesMonitorList::~MonitorList() { 877c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes MutexLock mu(lock_); 878c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes STLDeleteElements(&list_); 879c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 880c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 881c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughesvoid MonitorList::Add(Monitor* m) { 882c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes MutexLock mu(lock_); 883c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes list_.push_front(m); 884c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 885c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 886c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughesvoid MonitorList::SweepMonitorList(Heap::IsMarkedTester is_marked, void* arg) { 887c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes MutexLock mu(lock_); 888c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes typedef std::list<Monitor*>::iterator It; // TODO: C++0x auto 889c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes It it = list_.begin(); 890c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes while (it != list_.end()) { 891c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes Monitor* m = *it; 892c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes if (!is_marked(m->GetObject(), arg)) { 8934dd9b4d95eec9db5338fb9bf132f9bb8facf6cf4Elliott Hughes VLOG(monitor) << "freeing monitor " << m << " belonging to unmarked object " << m->GetObject(); 894c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes delete m; 895c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes it = list_.erase(it); 896c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes } else { 897c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes ++it; 898c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes } 899c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes } 900c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes} 901c33a32bccc4c66ed82ce3a580b16636399385cb4Elliott Hughes 9025f79133a435ebcb20000370d56046fe01201dd80Elliott Hughes} // namespace art 903