--- a/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentGCThread.cpp Thu Nov 20 11:39:42 2008 -0800
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,314 +0,0 @@
-/*
- * Copyright 2001-2005 Sun Microsystems, Inc. All Rights Reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 only, as
- * published by the Free Software Foundation.
- *
- * This code is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
- * version 2 for more details (a copy is included in the LICENSE file that
- * accompanied this code).
- *
- * You should have received a copy of the GNU General Public License version
- * 2 along with this work; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
- * CA 95054 USA or visit www.sun.com if you need additional information or
- * have any questions.
- *
- */
-
-// CopyrightVersion 1.2
-
-# include "incls/_precompiled.incl"
-# include "incls/_concurrentGCThread.cpp.incl"
-
-bool ConcurrentGCThread::_should_terminate = false;
-bool ConcurrentGCThread::_has_terminated = false;
-int ConcurrentGCThread::_CGC_flag = CGC_nil;
-
-SuspendibleThreadSet ConcurrentGCThread::_sts;
-
-ConcurrentGCThread::ConcurrentGCThread() {
- _sts.initialize();
-};
-
-void ConcurrentGCThread::stopWorldAndDo(VoidClosure* op) {
- MutexLockerEx x(Heap_lock,
- Mutex::_no_safepoint_check_flag);
- // warning("CGC: about to try stopping world");
- SafepointSynchronize::begin();
- // warning("CGC: successfully stopped world");
- op->do_void();
- SafepointSynchronize::end();
- // warning("CGC: successfully restarted world");
-}
-
-void ConcurrentGCThread::safepoint_synchronize() {
- _sts.suspend_all();
-}
-
-void ConcurrentGCThread::safepoint_desynchronize() {
- _sts.resume_all();
-}
-
-void ConcurrentGCThread::create_and_start() {
- if (os::create_thread(this, os::cgc_thread)) {
- // XXX: need to set this to low priority
- // unless "agressive mode" set; priority
- // should be just less than that of VMThread.
- os::set_priority(this, NearMaxPriority);
- if (!_should_terminate && !DisableStartThread) {
- os::start_thread(this);
- }
- }
-}
-
-void ConcurrentGCThread::initialize_in_thread() {
- this->record_stack_base_and_size();
- this->initialize_thread_local_storage();
- this->set_active_handles(JNIHandleBlock::allocate_block());
- // From this time Thread::current() should be working.
- assert(this == Thread::current(), "just checking");
-}
-
-void ConcurrentGCThread::wait_for_universe_init() {
- MutexLockerEx x(CGC_lock, Mutex::_no_safepoint_check_flag);
- while (!is_init_completed() && !_should_terminate) {
- CGC_lock->wait(Mutex::_no_safepoint_check_flag, 200);
- }
-}
-
-void ConcurrentGCThread::terminate() {
- // Signal that it is terminated
- {
- MutexLockerEx mu(Terminator_lock,
- Mutex::_no_safepoint_check_flag);
- _has_terminated = true;
- Terminator_lock->notify();
- }
-
- // Thread destructor usually does this..
- ThreadLocalStorage::set_thread(NULL);
-}
-
-
-void SuspendibleThreadSet::initialize_work() {
- MutexLocker x(STS_init_lock);
- if (!_initialized) {
- _m = new Monitor(Mutex::leaf,
- "SuspendibleThreadSetLock", true);
- _async = 0;
- _async_stop = false;
- _async_stopped = 0;
- _initialized = true;
- }
-}
-
-void SuspendibleThreadSet::join() {
- initialize();
- MutexLockerEx x(_m, Mutex::_no_safepoint_check_flag);
- while (_async_stop) _m->wait(Mutex::_no_safepoint_check_flag);
- _async++;
- assert(_async > 0, "Huh.");
-}
-
-void SuspendibleThreadSet::leave() {
- assert(_initialized, "Must be initialized.");
- MutexLockerEx x(_m, Mutex::_no_safepoint_check_flag);
- _async--;
- assert(_async >= 0, "Huh.");
- if (_async_stop) _m->notify_all();
-}
-
-void SuspendibleThreadSet::yield(const char* id) {
- assert(_initialized, "Must be initialized.");
- if (_async_stop) {
- MutexLockerEx x(_m, Mutex::_no_safepoint_check_flag);
- if (_async_stop) {
- _async_stopped++;
- assert(_async_stopped > 0, "Huh.");
- if (_async_stopped == _async) {
- if (ConcGCYieldTimeout > 0) {
- double now = os::elapsedTime();
- guarantee((now - _suspend_all_start) * 1000.0 <
- (double)ConcGCYieldTimeout,
- "Long delay; whodunit?");
- }
- }
- _m->notify_all();
- while (_async_stop) _m->wait(Mutex::_no_safepoint_check_flag);
- _async_stopped--;
- assert(_async >= 0, "Huh");
- _m->notify_all();
- }
- }
-}
-
-void SuspendibleThreadSet::suspend_all() {
- initialize(); // If necessary.
- if (ConcGCYieldTimeout > 0) {
- _suspend_all_start = os::elapsedTime();
- }
- MutexLockerEx x(_m, Mutex::_no_safepoint_check_flag);
- assert(!_async_stop, "Only one at a time.");
- _async_stop = true;
- while (_async_stopped < _async) _m->wait(Mutex::_no_safepoint_check_flag);
-}
-
-void SuspendibleThreadSet::resume_all() {
- assert(_initialized, "Must be initialized.");
- MutexLockerEx x(_m, Mutex::_no_safepoint_check_flag);
- assert(_async_stopped == _async, "Huh.");
- _async_stop = false;
- _m->notify_all();
-}
-
-static void _sltLoop(JavaThread* thread, TRAPS) {
- SurrogateLockerThread* slt = (SurrogateLockerThread*)thread;
- slt->loop();
-}
-
-SurrogateLockerThread::SurrogateLockerThread() :
- JavaThread(&_sltLoop),
- _monitor(Mutex::nonleaf, "SLTMonitor"),
- _buffer(empty)
-{}
-
-SurrogateLockerThread* SurrogateLockerThread::make(TRAPS) {
- klassOop k =
- SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_Thread(),
- true, CHECK_NULL);
- instanceKlassHandle klass (THREAD, k);
- instanceHandle thread_oop = klass->allocate_instance_handle(CHECK_NULL);
-
- const char thread_name[] = "Surrogate Locker Thread (CMS)";
- Handle string = java_lang_String::create_from_str(thread_name, CHECK_NULL);
-
- // Initialize thread_oop to put it into the system threadGroup
- Handle thread_group (THREAD, Universe::system_thread_group());
- JavaValue result(T_VOID);
- JavaCalls::call_special(&result, thread_oop,
- klass,
- vmSymbolHandles::object_initializer_name(),
- vmSymbolHandles::threadgroup_string_void_signature(),
- thread_group,
- string,
- CHECK_NULL);
-
- SurrogateLockerThread* res;
- {
- MutexLocker mu(Threads_lock);
- res = new SurrogateLockerThread();
-
- // At this point it may be possible that no osthread was created for the
- // JavaThread due to lack of memory. We would have to throw an exception
- // in that case. However, since this must work and we do not allow
- // exceptions anyway, check and abort if this fails.
- if (res == NULL || res->osthread() == NULL) {
- vm_exit_during_initialization("java.lang.OutOfMemoryError",
- "unable to create new native thread");
- }
- java_lang_Thread::set_thread(thread_oop(), res);
- java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
- java_lang_Thread::set_daemon(thread_oop());
-
- res->set_threadObj(thread_oop());
- Threads::add(res);
- Thread::start(res);
- }
- os::yield(); // This seems to help with initial start-up of SLT
- return res;
-}
-
-void SurrogateLockerThread::manipulatePLL(SLT_msg_type msg) {
- MutexLockerEx x(&_monitor, Mutex::_no_safepoint_check_flag);
- assert(_buffer == empty, "Should be empty");
- assert(msg != empty, "empty message");
- _buffer = msg;
- while (_buffer != empty) {
- _monitor.notify();
- _monitor.wait(Mutex::_no_safepoint_check_flag);
- }
-}
-
-// ======= Surrogate Locker Thread =============
-
-void SurrogateLockerThread::loop() {
- BasicLock pll_basic_lock;
- SLT_msg_type msg;
- debug_only(unsigned int owned = 0;)
-
- while (/* !isTerminated() */ 1) {
- {
- MutexLocker x(&_monitor);
- // Since we are a JavaThread, we can't be here at a safepoint.
- assert(!SafepointSynchronize::is_at_safepoint(),
- "SLT is a JavaThread");
- // wait for msg buffer to become non-empty
- while (_buffer == empty) {
- _monitor.notify();
- _monitor.wait();
- }
- msg = _buffer;
- }
- switch(msg) {
- case acquirePLL: {
- instanceRefKlass::acquire_pending_list_lock(&pll_basic_lock);
- debug_only(owned++;)
- break;
- }
- case releaseAndNotifyPLL: {
- assert(owned > 0, "Don't have PLL");
- instanceRefKlass::release_and_notify_pending_list_lock(&pll_basic_lock);
- debug_only(owned--;)
- break;
- }
- case empty:
- default: {
- guarantee(false,"Unexpected message in _buffer");
- break;
- }
- }
- {
- MutexLocker x(&_monitor);
- // Since we are a JavaThread, we can't be here at a safepoint.
- assert(!SafepointSynchronize::is_at_safepoint(),
- "SLT is a JavaThread");
- _buffer = empty;
- _monitor.notify();
- }
- }
- assert(!_monitor.owned_by_self(), "Should unlock before exit.");
-}
-
-
-// ===== STS Access From Outside CGCT =====
-
-void ConcurrentGCThread::stsYield(const char* id) {
- assert( Thread::current()->is_ConcurrentGC_thread(),
- "only a conc GC thread can call this" );
- _sts.yield(id);
-}
-
-bool ConcurrentGCThread::stsShouldYield() {
- assert( Thread::current()->is_ConcurrentGC_thread(),
- "only a conc GC thread can call this" );
- return _sts.should_yield();
-}
-
-void ConcurrentGCThread::stsJoin() {
- assert( Thread::current()->is_ConcurrentGC_thread(),
- "only a conc GC thread can call this" );
- _sts.join();
-}
-
-void ConcurrentGCThread::stsLeave() {
- assert( Thread::current()->is_ConcurrentGC_thread(),
- "only a conc GC thread can call this" );
- _sts.leave();
-}