jdk-sandbox: comparison src/hotspot/share/runtime/synchronizer.cpp

equal deleted inserted replaced

-:13588c901957
+:9cf78a70fa4f
 #include "memory/allocation.inline.hpp"
 #include "memory/metaspaceShared.hpp"
 #include "memory/padded.hpp"
 #include "memory/resourceArea.hpp"
 #include "memory/universe.hpp"
-#include "oops/markOop.hpp"
+#include "oops/markWord.hpp"
 #include "oops/oop.inline.hpp"
 #include "runtime/atomic.hpp"
 #include "runtime/biasedLocking.hpp"
 #include "runtime/handles.inline.hpp"
 #include "runtime/interfaceSupport.inline.hpp"
 #define NINFLATIONLOCKS 256
 static volatile intptr_t gInflationLocks[NINFLATIONLOCKS];
 // global list of blocks of monitors
-PaddedEnd<ObjectMonitor> * volatile ObjectSynchronizer::gBlockList = NULL;
+PaddedObjectMonitor* volatile ObjectSynchronizer::g_block_list = NULL;
-// global monitor free list
+// Global ObjectMonitor free list. Newly allocated and deflated
-ObjectMonitor * volatile ObjectSynchronizer::gFreeList  = NULL;
+// ObjectMonitors are prepended here.
-// global monitor in-use list, for moribund threads,
+ObjectMonitor* volatile ObjectSynchronizer::g_free_list = NULL;
-// monitors they inflated need to be scanned for deflation
+// Global ObjectMonitor in-use list. When a JavaThread is exiting,
-ObjectMonitor * volatile ObjectSynchronizer::gOmInUseList  = NULL;
+// ObjectMonitors on its per-thread in-use list are prepended here.
-// count of entries in gOmInUseList
+ObjectMonitor* volatile ObjectSynchronizer::g_om_in_use_list = NULL;
-int ObjectSynchronizer::gOmInUseCount = 0;
+int ObjectSynchronizer::g_om_in_use_count = 0;  // # on g_om_in_use_list
-static volatile intptr_t gListLock = 0;      // protects global monitor lists
+static volatile intptr_t gListLock = 0;   // protects global monitor lists
-static volatile int gMonitorFreeCount  = 0;  // # on gFreeList
+static volatile int g_om_free_count = 0;  // # on g_free_list
-static volatile int gMonitorPopulation = 0;  // # Extant -- in circulation
+static volatile int g_om_population = 0;  // # Extant -- in circulation
 #define CHAINMARKER (cast_to_oop<intptr_t>(-1))
 // =====================> Quick functions
 //   synchronized (someobj) { .... ; notify(); }
 // That is, we find a notify() or notifyAll() call that immediately precedes
 // the monitorexit operation.  In that case the JIT could fuse the operations
 // into a single notifyAndExit() runtime primitive.
-bool ObjectSynchronizer::quick_notify(oopDesc * obj, Thread * self, bool all) {
+bool ObjectSynchronizer::quick_notify(oopDesc* obj, Thread* self, bool all) {
 assert(!SafepointSynchronize::is_at_safepoint(), "invariant");
 assert(self->is_Java_thread(), "invariant");
 assert(((JavaThread *) self)->thread_state() == _thread_in_Java, "invariant");
 NoSafepointVerifier nsv;
 if (obj == NULL) return false;  // slow-path for invalid obj
-const markOop mark = obj->mark();
+const markWord mark = obj->mark();
-if (mark->has_locker() && self->is_lock_owned((address)mark->locker())) {
+if (mark.has_locker() && self->is_lock_owned((address)mark.locker())) {
 // Degenerate notify
 // stack-locked by caller so by definition the implied waitset is empty.
 return true;
 }
-if (mark->has_monitor()) {
+if (mark.has_monitor()) {
-ObjectMonitor * const mon = mark->monitor();
+ObjectMonitor* const mon = mark.monitor();
-assert(oopDesc::equals((oop) mon->object(), obj), "invariant");
+assert(mon->object() == obj, "invariant");
 if (mon->owner() != self) return false;  // slow-path for IMS exception
 if (mon->first_waiter() != NULL) {
 // We have one or more waiters. Since this is an inflated monitor
 // that we own, we can transfer one or more threads from the waitset
 if (all) {
 DTRACE_MONITOR_PROBE(notifyAll, mon, obj, self);
 } else {
 DTRACE_MONITOR_PROBE(notify, mon, obj, self);
 }
-int tally = 0;
+int free_count = 0;
 do {
 mon->INotify(self);
-++tally;
+++free_count;
 } while (mon->first_waiter() != NULL && all);
-OM_PERFDATA_OP(Notifications, inc(tally));
+OM_PERFDATA_OP(Notifications, inc(free_count));
 }
 return true;
 }
 // biased locking and any other IMS exception states take the slow-path
 // been too big if it were to have included support for the cases of inflated
 // recursive enter and exit, so they go here instead.
 // Note that we can't safely call AsyncPrintJavaStack() from within
 // quick_enter() as our thread state remains _in_Java.
-bool ObjectSynchronizer::quick_enter(oop obj, Thread * Self,
+bool ObjectSynchronizer::quick_enter(oop obj, Thread* self,
 BasicLock * lock) {
 assert(!SafepointSynchronize::is_at_safepoint(), "invariant");
-assert(Self->is_Java_thread(), "invariant");
+assert(self->is_Java_thread(), "invariant");
-assert(((JavaThread *) Self)->thread_state() == _thread_in_Java, "invariant");
+assert(((JavaThread *) self)->thread_state() == _thread_in_Java, "invariant");
 NoSafepointVerifier nsv;
 if (obj == NULL) return false;       // Need to throw NPE
-const markOop mark = obj->mark();
+const markWord mark = obj->mark();
-if (mark->has_monitor()) {
+if (mark.has_monitor()) {
-ObjectMonitor * const m = mark->monitor();
+ObjectMonitor* const m = mark.monitor();
-assert(oopDesc::equals((oop) m->object(), obj), "invariant");
+assert(m->object() == obj, "invariant");
-Thread * const owner = (Thread *) m->_owner;
+Thread* const owner = (Thread *) m->_owner;
 // Lock contention and Transactional Lock Elision (TLE) diagnostics
 // and observability
 // Case: light contention possibly amenable to TLE
 // Case: TLE inimical operations such as nested/recursive synchronization
-if (owner == Self) {
+if (owner == self) {
 m->_recursions++;
 return true;
 }
 // This Java Monitor is inflated so obj's header will never be
 // performance reasons, stack walkers generally first check for
 // Biased Locking in the object's header, the second check is for
 // stack-locking in the object's header, the third check is for
 // recursive stack-locking in the displaced header in the BasicLock,
 // and last are the inflated Java Monitor (ObjectMonitor) checks.
-lock->set_displaced_header(markOopDesc::unused_mark());
+lock->set_displaced_header(markWord::unused_mark());
-if (owner == NULL && Atomic::replace_if_null(Self, &(m->_owner))) {
+if (owner == NULL && Atomic::replace_if_null(self, &(m->_owner))) {
 assert(m->_recursions == 0, "invariant");
-assert(m->_owner == Self, "invariant");
 return true;
 }
 }
 // Note that we could inflate in quick_enter.
 return false;        // revert to slow-path
 }
 // -----------------------------------------------------------------------------
-//  Fast Monitor Enter/Exit
+// Monitor Enter/Exit
-// This the fast monitor enter. The interpreter and compiler use
+// The interpreter and compiler assembly code tries to lock using the fast path
-// some assembly copies of this code. Make sure update those code
+// of this algorithm. Make sure to update that code if the following function is
-// if the following function is changed. The implementation is
+// changed. The implementation is extremely sensitive to race condition. Be careful.
-// extremely sensitive to race condition. Be careful.
+void ObjectSynchronizer::enter(Handle obj, BasicLock* lock, TRAPS) {
-void ObjectSynchronizer::fast_enter(Handle obj, BasicLock* lock,
-bool attempt_rebias, TRAPS) {
 if (UseBiasedLocking) {
 if (!SafepointSynchronize::is_at_safepoint()) {
-BiasedLocking::Condition cond = BiasedLocking::revoke_and_rebias(obj, attempt_rebias, THREAD);
+BiasedLocking::revoke(obj, THREAD);
-if (cond == BiasedLocking::BIAS_REVOKED_AND_REBIASED) {
-return;
-}
 } else {
-assert(!attempt_rebias, "can not rebias toward VM thread");
 BiasedLocking::revoke_at_safepoint(obj);
 }
-assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
+}
-}
+markWord mark = obj->mark();
-slow_enter(obj, lock, THREAD);
+assert(!mark.has_bias_pattern(), "should not see bias pattern here");
-}
+if (mark.is_neutral()) {
-void ObjectSynchronizer::fast_exit(oop object, BasicLock* lock, TRAPS) {
+// Anticipate successful CAS -- the ST of the displaced mark must
-markOop mark = object->mark();
+// be visible <= the ST performed by the CAS.
+lock->set_displaced_header(mark);
+if (mark == obj()->cas_set_mark(markWord::from_pointer(lock), mark)) {
+return;
+}
+// Fall through to inflate() ...
+} else if (mark.has_locker() &&
+THREAD->is_lock_owned((address)mark.locker())) {
+assert(lock != mark.locker(), "must not re-lock the same lock");
+assert(lock != (BasicLock*)obj->mark().value(), "don't relock with same BasicLock");
+lock->set_displaced_header(markWord::from_pointer(NULL));
+return;
+}
+// The object header will never be displaced to this lock,
+// so it does not matter what the value is, except that it
+// must be non-zero to avoid looking like a re-entrant lock,
+// and must not look locked either.
+lock->set_displaced_header(markWord::unused_mark());
+inflate(THREAD, obj(), inflate_cause_monitor_enter)->enter(THREAD);
+}
+void ObjectSynchronizer::exit(oop object, BasicLock* lock, TRAPS) {
+markWord mark = object->mark();
 // We cannot check for Biased Locking if we are racing an inflation.
-assert(mark == markOopDesc::INFLATING() ||
+assert(mark == markWord::INFLATING() ||
-!mark->has_bias_pattern(), "should not see bias pattern here");
+!mark.has_bias_pattern(), "should not see bias pattern here");
-markOop dhw = lock->displaced_header();
+markWord dhw = lock->displaced_header();
-if (dhw == NULL) {
+if (dhw.value() == 0) {
 // If the displaced header is NULL, then this exit matches up with
 // a recursive enter. No real work to do here except for diagnostics.
 #ifndef PRODUCT
-if (mark != markOopDesc::INFLATING()) {
+if (mark != markWord::INFLATING()) {
 // Only do diagnostics if we are not racing an inflation. Simply
 // exiting a recursive enter of a Java Monitor that is being
 // inflated is safe; see the has_monitor() comment below.
-assert(!mark->is_neutral(), "invariant");
+assert(!mark.is_neutral(), "invariant");
-assert(!mark->has_locker() ||
+assert(!mark.has_locker() ||
-THREAD->is_lock_owned((address)mark->locker()), "invariant");
+THREAD->is_lock_owned((address)mark.locker()), "invariant");
-if (mark->has_monitor()) {
+if (mark.has_monitor()) {
 // The BasicLock's displaced_header is marked as a recursive
 // enter and we have an inflated Java Monitor (ObjectMonitor).
 // This is a special case where the Java Monitor was inflated
 // after this thread entered the stack-lock recursively. When a
 // Java Monitor is inflated, we cannot safely walk the Java
 // Monitor owner's stack and update the BasicLocks because a
 // Java Monitor can be asynchronously inflated by a thread that
 // does not own the Java Monitor.
-ObjectMonitor * m = mark->monitor();
+ObjectMonitor* m = mark.monitor();
 assert(((oop)(m->object()))->mark() == mark, "invariant");
 assert(m->is_entered(THREAD), "invariant");
 }
 }
 #endif
 return;
 }
-if (mark == (markOop) lock) {
+if (mark == markWord::from_pointer(lock)) {
 // If the object is stack-locked by the current thread, try to
 // swing the displaced header from the BasicLock back to the mark.
-assert(dhw->is_neutral(), "invariant");
+assert(dhw.is_neutral(), "invariant");
 if (object->cas_set_mark(dhw, mark) == mark) {
 return;
 }
 }
 // We have to take the slow-path of possible inflation and then exit.
 inflate(THREAD, object, inflate_cause_vm_internal)->exit(true, THREAD);
-}
-// -----------------------------------------------------------------------------
-// Interpreter/Compiler Slow Case
-// This routine is used to handle interpreter/compiler slow case
-// We don't need to use fast path here, because it must have been
-// failed in the interpreter/compiler code.
-void ObjectSynchronizer::slow_enter(Handle obj, BasicLock* lock, TRAPS) {
-markOop mark = obj->mark();
-assert(!mark->has_bias_pattern(), "should not see bias pattern here");
-if (mark->is_neutral()) {
-// Anticipate successful CAS -- the ST of the displaced mark must
-// be visible <= the ST performed by the CAS.
-lock->set_displaced_header(mark);
-if (mark == obj()->cas_set_mark((markOop) lock, mark)) {
-return;
-}
-// Fall through to inflate() ...
-} else if (mark->has_locker() &&
-THREAD->is_lock_owned((address)mark->locker())) {
-assert(lock != mark->locker(), "must not re-lock the same lock");
-assert(lock != (BasicLock*)obj->mark(), "don't relock with same BasicLock");
-lock->set_displaced_header(NULL);
-return;
-}
-// The object header will never be displaced to this lock,
-// so it does not matter what the value is, except that it
-// must be non-zero to avoid looking like a re-entrant lock,
-// and must not look locked either.
-lock->set_displaced_header(markOopDesc::unused_mark());
-inflate(THREAD, obj(), inflate_cause_monitor_enter)->enter(THREAD);
-}
-// This routine is used to handle interpreter/compiler slow case
-// We don't need to use fast path here, because it must have
-// failed in the interpreter/compiler code. Simply use the heavy
-// weight monitor should be ok, unless someone find otherwise.
-void ObjectSynchronizer::slow_exit(oop object, BasicLock* lock, TRAPS) {
-fast_exit(object, lock, THREAD);
 }
 // -----------------------------------------------------------------------------
 // Class Loader  support to workaround deadlocks on the class loader lock objects
 // Also used by GC
 //  4) reenter lock1 with original recursion count
 //  5) lock lock2
 // NOTE: must use heavy weight monitor to handle complete_exit/reenter()
 intptr_t ObjectSynchronizer::complete_exit(Handle obj, TRAPS) {
 if (UseBiasedLocking) {
-BiasedLocking::revoke_and_rebias(obj, false, THREAD);
+BiasedLocking::revoke(obj, THREAD);
-assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
+assert(!obj->mark().has_bias_pattern(), "biases should be revoked by now");
 }
 ObjectMonitor* monitor = inflate(THREAD, obj(), inflate_cause_vm_internal);
 return monitor->complete_exit(THREAD);
 }
 // NOTE: must use heavy weight monitor to handle complete_exit/reenter()
 void ObjectSynchronizer::reenter(Handle obj, intptr_t recursion, TRAPS) {
 if (UseBiasedLocking) {
-BiasedLocking::revoke_and_rebias(obj, false, THREAD);
+BiasedLocking::revoke(obj, THREAD);
-assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
+assert(!obj->mark().has_bias_pattern(), "biases should be revoked by now");
 }
 ObjectMonitor* monitor = inflate(THREAD, obj(), inflate_cause_vm_internal);
 monitor->reenter(recursion, THREAD);
 // JNI locks on java objects
 // NOTE: must use heavy weight monitor to handle jni monitor enter
 void ObjectSynchronizer::jni_enter(Handle obj, TRAPS) {
 // the current locking is from JNI instead of Java code
 if (UseBiasedLocking) {
-BiasedLocking::revoke_and_rebias(obj, false, THREAD);
+BiasedLocking::revoke(obj, THREAD);
-assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
+assert(!obj->mark().has_bias_pattern(), "biases should be revoked by now");
 }
 THREAD->set_current_pending_monitor_is_from_java(false);
 inflate(THREAD, obj(), inflate_cause_jni_enter)->enter(THREAD);
 THREAD->set_current_pending_monitor_is_from_java(true);
 }
 // NOTE: must use heavy weight monitor to handle jni monitor exit
 void ObjectSynchronizer::jni_exit(oop obj, Thread* THREAD) {
 if (UseBiasedLocking) {
 Handle h_obj(THREAD, obj);
-BiasedLocking::revoke_and_rebias(h_obj, false, THREAD);
+BiasedLocking::revoke(h_obj, THREAD);
 obj = h_obj();
 }
-assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
+assert(!obj->mark().has_bias_pattern(), "biases should be revoked by now");
 ObjectMonitor* monitor = inflate(THREAD, obj, inflate_cause_jni_exit);
-// If this thread has locked the object, exit the monitor.  Note:  can't use
+// If this thread has locked the object, exit the monitor. We
-// monitor->check(CHECK); must exit even if an exception is pending.
+// intentionally do not use CHECK here because we must exit the
-if (monitor->check(THREAD)) {
+// monitor even if an exception is pending.
+if (monitor->check_owner(THREAD)) {
 monitor->exit(true, THREAD);
 }
 }
 // -----------------------------------------------------------------------------
 // Internal VM locks on java objects
 // standard constructor, allows locking failures
-ObjectLocker::ObjectLocker(Handle obj, Thread* thread, bool doLock) {
+ObjectLocker::ObjectLocker(Handle obj, Thread* thread, bool do_lock) {
-_dolock = doLock;
+_dolock = do_lock;
 _thread = thread;
-debug_only(if (StrictSafepointChecks) _thread->check_for_valid_safepoint_state(false);)
+_thread->check_for_valid_safepoint_state();
 _obj = obj;
 if (_dolock) {
-ObjectSynchronizer::fast_enter(_obj, &_lock, false, _thread);
+ObjectSynchronizer::enter(_obj, &_lock, _thread);
 }
 }
 ObjectLocker::~ObjectLocker() {
 if (_dolock) {
-ObjectSynchronizer::fast_exit(_obj(), &_lock, _thread);
+ObjectSynchronizer::exit(_obj(), &_lock, _thread);
 }
 }
 // -----------------------------------------------------------------------------
 //  Wait/Notify/NotifyAll
 // NOTE: must use heavy weight monitor to handle wait()
 int ObjectSynchronizer::wait(Handle obj, jlong millis, TRAPS) {
 if (UseBiasedLocking) {
-BiasedLocking::revoke_and_rebias(obj, false, THREAD);
+BiasedLocking::revoke(obj, THREAD);
-assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
+assert(!obj->mark().has_bias_pattern(), "biases should be revoked by now");
 }
 if (millis < 0) {
 THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "timeout value is negative");
 }
 ObjectMonitor* monitor = inflate(THREAD, obj(), inflate_cause_wait);
 // and change this function back into a "void" func.
 // DTRACE_MONITOR_PROBE(waited, monitor, obj(), THREAD);
 return dtrace_waited_probe(monitor, obj, THREAD);
 }
-void ObjectSynchronizer::waitUninterruptibly(Handle obj, jlong millis, TRAPS) {
+void ObjectSynchronizer::wait_uninterruptibly(Handle obj, jlong millis, TRAPS) {
 if (UseBiasedLocking) {
-BiasedLocking::revoke_and_rebias(obj, false, THREAD);
+BiasedLocking::revoke(obj, THREAD);
-assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
+assert(!obj->mark().has_bias_pattern(), "biases should be revoked by now");
 }
 if (millis < 0) {
 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "timeout value is negative");
 }
 inflate(THREAD, obj(), inflate_cause_wait)->wait(millis, false, THREAD);
 }
 void ObjectSynchronizer::notify(Handle obj, TRAPS) {
 if (UseBiasedLocking) {
-BiasedLocking::revoke_and_rebias(obj, false, THREAD);
+BiasedLocking::revoke(obj, THREAD);
-assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
+assert(!obj->mark().has_bias_pattern(), "biases should be revoked by now");
 }
-markOop mark = obj->mark();
+markWord mark = obj->mark();
-if (mark->has_locker() && THREAD->is_lock_owned((address)mark->locker())) {
+if (mark.has_locker() && THREAD->is_lock_owned((address)mark.locker())) {
 return;
 }
 inflate(THREAD, obj(), inflate_cause_notify)->notify(THREAD);
 }
 // NOTE: see comment of notify()
 void ObjectSynchronizer::notifyall(Handle obj, TRAPS) {
 if (UseBiasedLocking) {
-BiasedLocking::revoke_and_rebias(obj, false, THREAD);
+BiasedLocking::revoke(obj, THREAD);
-assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
+assert(!obj->mark().has_bias_pattern(), "biases should be revoked by now");
 }
-markOop mark = obj->mark();
+markWord mark = obj->mark();
-if (mark->has_locker() && THREAD->is_lock_owned((address)mark->locker())) {
+if (mark.has_locker() && THREAD->is_lock_owned((address)mark.locker())) {
 return;
 }
 inflate(THREAD, obj(), inflate_cause_notify)->notifyAll(THREAD);
 }
 struct SharedGlobals {
 char         _pad_prefix[DEFAULT_CACHE_LINE_SIZE];
 // These are highly shared mostly-read variables.
 // To avoid false-sharing they need to be the sole occupants of a cache line.
-volatile int stwRandom;
+volatile int stw_random;
-volatile int stwCycle;
+volatile int stw_cycle;
 DEFINE_PAD_MINUS_SIZE(1, DEFAULT_CACHE_LINE_SIZE, sizeof(volatile int) * 2);
 // Hot RW variable -- Sequester to avoid false-sharing
-volatile int hcSequence;
+volatile int hc_sequence;
 DEFINE_PAD_MINUS_SIZE(2, DEFAULT_CACHE_LINE_SIZE, sizeof(volatile int));
 };
 static SharedGlobals GVars;
 static int MonitorScavengeThreshold = 1000000;
 static volatile int ForceMonitorScavenge = 0; // Scavenge required and pending
-static markOop ReadStableMark(oop obj) {
+static markWord read_stable_mark(oop obj) {
-markOop mark = obj->mark();
+markWord mark = obj->mark();
-if (!mark->is_being_inflated()) {
+if (!mark.is_being_inflated()) {
 return mark;       // normal fast-path return
 }
 int its = 0;
 for (;;) {
-markOop mark = obj->mark();
+markWord mark = obj->mark();
-if (!mark->is_being_inflated()) {
+if (!mark.is_being_inflated()) {
 return mark;    // normal fast-path return
 }
 // The object is being inflated by some other thread.
-// The caller of ReadStableMark() must wait for inflation to complete.
+// The caller of read_stable_mark() must wait for inflation to complete.
 // Avoid live-lock
 // TODO: consider calling SafepointSynchronize::do_call_back() while
 // spinning to see if there's a safepoint pending.  If so, immediately
 // yielding or blocking would be appropriate.  Avoid spinning while
 // there is a safepoint pending.
 int ix = (cast_from_oop<intptr_t>(obj) >> 5) & (NINFLATIONLOCKS-1);
 int YieldThenBlock = 0;
 assert(ix >= 0 && ix < NINFLATIONLOCKS, "invariant");
 assert((NINFLATIONLOCKS & (NINFLATIONLOCKS-1)) == 0, "invariant");
 Thread::muxAcquire(gInflationLocks + ix, "gInflationLock");
-while (obj->mark() == markOopDesc::INFLATING()) {
+while (obj->mark() == markWord::INFLATING()) {
 // Beware: NakedYield() is advisory and has almost no effect on some platforms
-// so we periodically call Self->_ParkEvent->park(1).
+// so we periodically call self->_ParkEvent->park(1).
 // We use a mixed spin/yield/block mechanism.
 if ((YieldThenBlock++) >= 16) {
 Thread::current()->_ParkEvent->park(1);
 } else {
 os::naked_yield();
 }
 // hashCode() generation :
 //
 // Possibilities:
-// * MD5Digest of {obj,stwRandom}
+// * MD5Digest of {obj,stw_random}
-// * CRC32 of {obj,stwRandom} or any linear-feedback shift register function.
+// * CRC32 of {obj,stw_random} or any linear-feedback shift register function.
 // * A DES- or AES-style SBox[] mechanism
 // * One of the Phi-based schemes, such as:
 //   2654435761 = 2^32 * Phi (golden ratio)
-//   HashCodeValue = ((uintptr_t(obj) >> 3) * 2654435761) ^ GVars.stwRandom ;
+//   HashCodeValue = ((uintptr_t(obj) >> 3) * 2654435761) ^ GVars.stw_random ;
 // * A variation of Marsaglia's shift-xor RNG scheme.
-// * (obj ^ stwRandom) is appealing, but can result
+// * (obj ^ stw_random) is appealing, but can result
 //   in undesirable regularity in the hashCode values of adjacent objects
 //   (objects allocated back-to-back, in particular).  This could potentially
 //   result in hashtable collisions and reduced hashtable efficiency.
 //   There are simple ways to "diffuse" the middle address bits over the
 //   generated hashCode values:
-static inline intptr_t get_next_hash(Thread * Self, oop obj) {
+static inline intptr_t get_next_hash(Thread* self, oop obj) {
 intptr_t value = 0;
 if (hashCode == 0) {
 // This form uses global Park-Miller RNG.
 // On MP system we'll have lots of RW access to a global, so the
 // mechanism induces lots of coherency traffic.
 value = os::random();
 } else if (hashCode == 1) {
 // This variation has the property of being stable (idempotent)
 // between STW operations.  This can be useful in some of the 1-0
 // synchronization schemes.
-intptr_t addrBits = cast_from_oop<intptr_t>(obj) >> 3;
+intptr_t addr_bits = cast_from_oop<intptr_t>(obj) >> 3;
-value = addrBits ^ (addrBits >> 5) ^ GVars.stwRandom;
+value = addr_bits ^ (addr_bits >> 5) ^ GVars.stw_random;
 } else if (hashCode == 2) {
 value = 1;            // for sensitivity testing
 } else if (hashCode == 3) {
-value = ++GVars.hcSequence;
+value = ++GVars.hc_sequence;
 } else if (hashCode == 4) {
 value = cast_from_oop<intptr_t>(obj);
 } else {
 // Marsaglia's xor-shift scheme with thread-specific state
 // This is probably the best overall implementation -- we'll
 // likely make this the default in future releases.
-unsigned t = Self->_hashStateX;
+unsigned t = self->_hashStateX;
 t ^= (t << 11);
-Self->_hashStateX = Self->_hashStateY;
+self->_hashStateX = self->_hashStateY;
-Self->_hashStateY = Self->_hashStateZ;
+self->_hashStateY = self->_hashStateZ;
-Self->_hashStateZ = Self->_hashStateW;
+self->_hashStateZ = self->_hashStateW;
-unsigned v = Self->_hashStateW;
+unsigned v = self->_hashStateW;
 v = (v ^ (v >> 19)) ^ (t ^ (t >> 8));
-Self->_hashStateW = v;
+self->_hashStateW = v;
 value = v;
 }
-value &= markOopDesc::hash_mask;
+value &= markWord::hash_mask;
 if (value == 0) value = 0xBAD;
-assert(value != markOopDesc::no_hash, "invariant");
+assert(value != markWord::no_hash, "invariant");
 return value;
 }
-intptr_t ObjectSynchronizer::FastHashCode(Thread * Self, oop obj) {
+intptr_t ObjectSynchronizer::FastHashCode(Thread* self, oop obj) {
 if (UseBiasedLocking) {
 // NOTE: many places throughout the JVM do not expect a safepoint
 // to be taken here, in particular most operations on perm gen
 // objects. However, we only ever bias Java instances and all of
 // the call sites of identity_hash that might revoke biases have
 // been checked to make sure they can handle a safepoint. The
 // added check of the bias pattern is to avoid useless calls to
 // thread-local storage.
-if (obj->mark()->has_bias_pattern()) {
+if (obj->mark().has_bias_pattern()) {
 // Handle for oop obj in case of STW safepoint
-Handle hobj(Self, obj);
+Handle hobj(self, obj);
 // Relaxing assertion for bug 6320749.
 assert(Universe::verify_in_progress() ||
 !SafepointSynchronize::is_at_safepoint(),
 "biases should not be seen by VM thread here");
-BiasedLocking::revoke_and_rebias(hobj, false, JavaThread::current());
+BiasedLocking::revoke(hobj, JavaThread::current());
 obj = hobj();
-assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
+assert(!obj->mark().has_bias_pattern(), "biases should be revoked by now");
 }
 }
 // hashCode() is a heap mutator ...
 // Relaxing assertion for bug 6320749.
 assert(Universe::verify_in_progress() || DumpSharedSpaces ||
 !SafepointSynchronize::is_at_safepoint(), "invariant");
 assert(Universe::verify_in_progress() || DumpSharedSpaces ||
-Self->is_Java_thread() , "invariant");
+self->is_Java_thread() , "invariant");
 assert(Universe::verify_in_progress() || DumpSharedSpaces ||
-((JavaThread *)Self)->thread_state() != _thread_blocked, "invariant");
+((JavaThread *)self)->thread_state() != _thread_blocked, "invariant");
 ObjectMonitor* monitor = NULL;
-markOop temp, test;
+markWord temp, test;
 intptr_t hash;
-markOop mark = ReadStableMark(obj);
+markWord mark = read_stable_mark(obj);
 // object should remain ineligible for biased locking
-assert(!mark->has_bias_pattern(), "invariant");
+assert(!mark.has_bias_pattern(), "invariant");
-if (mark->is_neutral()) {
+if (mark.is_neutral()) {
-hash = mark->hash();              // this is a normal header
+hash = mark.hash();               // this is a normal header
 if (hash != 0) {                  // if it has hash, just return it
 return hash;
 }
-hash = get_next_hash(Self, obj);  // allocate a new hash code
+hash = get_next_hash(self, obj);  // allocate a new hash code
-temp = mark->copy_set_hash(hash); // merge the hash code into header
+temp = mark.copy_set_hash(hash);  // merge the hash code into header
 // use (machine word version) atomic operation to install the hash
 test = obj->cas_set_mark(temp, mark);
 if (test == mark) {
 return hash;
 }
 // If atomic operation failed, we must inflate the header
 // into heavy weight monitor. We could add more code here
 // for fast path, but it does not worth the complexity.
-} else if (mark->has_monitor()) {
+} else if (mark.has_monitor()) {
-monitor = mark->monitor();
+monitor = mark.monitor();
 temp = monitor->header();
-assert(temp->is_neutral(), "invariant: header=" INTPTR_FORMAT, p2i(temp));
+assert(temp.is_neutral(), "invariant: header=" INTPTR_FORMAT, temp.value());
-hash = temp->hash();
+hash = temp.hash();
 if (hash != 0) {
 return hash;
 }
 // Skip to the following code to reduce code size
-} else if (Self->is_lock_owned((address)mark->locker())) {
+} else if (self->is_lock_owned((address)mark.locker())) {
-temp = mark->displaced_mark_helper(); // this is a lightweight monitor owned
+temp = mark.displaced_mark_helper(); // this is a lightweight monitor owned
-assert(temp->is_neutral(), "invariant: header=" INTPTR_FORMAT, p2i(temp));
+assert(temp.is_neutral(), "invariant: header=" INTPTR_FORMAT, temp.value());
-hash = temp->hash();              // by current thread, check if the displaced
+hash = temp.hash();                  // by current thread, check if the displaced
-if (hash != 0) {                  // header contains hash code
+if (hash != 0) {                     // header contains hash code
 return hash;
 }
 // WARNING:
 // The displaced header in the BasicLock on a thread's stack
 // is strictly immutable. It CANNOT be changed in ANY cases.
 // during an inflate() call so any change to that stack memory
 // may not propagate to other threads correctly.
 }
 // Inflate the monitor to set hash code
-monitor = inflate(Self, obj, inflate_cause_hash_code);
+monitor = inflate(self, obj, inflate_cause_hash_code);
 // Load displaced header and check it has hash code
 mark = monitor->header();
-assert(mark->is_neutral(), "invariant: header=" INTPTR_FORMAT, p2i(mark));
+assert(mark.is_neutral(), "invariant: header=" INTPTR_FORMAT, mark.value());
-hash = mark->hash();
+hash = mark.hash();
 if (hash == 0) {
-hash = get_next_hash(Self, obj);
+hash = get_next_hash(self, obj);
-temp = mark->copy_set_hash(hash); // merge hash code into header
+temp = mark.copy_set_hash(hash); // merge hash code into header
-assert(temp->is_neutral(), "invariant: header=" INTPTR_FORMAT, p2i(temp));
+assert(temp.is_neutral(), "invariant: header=" INTPTR_FORMAT, temp.value());
-test = Atomic::cmpxchg(temp, monitor->header_addr(), mark);
+uintptr_t v = Atomic::cmpxchg(temp.value(), (volatile uintptr_t*)monitor->header_addr(), mark.value());
+test = markWord(v);
 if (test != mark) {
-// The only update to the ObjectMonitor's header/dmw field
+// The only non-deflation update to the ObjectMonitor's
-// is to merge in the hash code. If someone adds a new usage
+// header/dmw field is to merge in the hash code. If someone
-// of the header/dmw field, please update this code.
+// adds a new usage of the header/dmw field, please update
-hash = test->hash();
+// this code.
-assert(test->is_neutral(), "invariant: header=" INTPTR_FORMAT, p2i(test));
+hash = test.hash();
+assert(test.is_neutral(), "invariant: header=" INTPTR_FORMAT, test.value());
 assert(hash != 0, "Trivial unexpected object/monitor header usage.");
 }
 }
 // We finally get the hash
 return hash;
 bool ObjectSynchronizer::current_thread_holds_lock(JavaThread* thread,
 Handle h_obj) {
 if (UseBiasedLocking) {
-BiasedLocking::revoke_and_rebias(h_obj, false, thread);
+BiasedLocking::revoke(h_obj, thread);
-assert(!h_obj->mark()->has_bias_pattern(), "biases should be revoked by now");
+assert(!h_obj->mark().has_bias_pattern(), "biases should be revoked by now");
 }
 assert(thread == JavaThread::current(), "Can only be called on current thread");
 oop obj = h_obj();
-markOop mark = ReadStableMark(obj);
+markWord mark = read_stable_mark(obj);
 // Uncontended case, header points to stack
-if (mark->has_locker()) {
+if (mark.has_locker()) {
-return thread->is_lock_owned((address)mark->locker());
+return thread->is_lock_owned((address)mark.locker());
 }
 // Contended case, header points to ObjectMonitor (tagged pointer)
-if (mark->has_monitor()) {
+if (mark.has_monitor()) {
-ObjectMonitor* monitor = mark->monitor();
+ObjectMonitor* monitor = mark.monitor();
 return monitor->is_entered(thread) != 0;
 }
 // Unlocked case, header in place
-assert(mark->is_neutral(), "sanity check");
+assert(mark.is_neutral(), "sanity check");
 return false;
 }
 // Be aware of this method could revoke bias of the lock object.
 // This method queries the ownership of the lock handle specified by 'h_obj'.
 assert(!SafepointSynchronize::is_at_safepoint(), "invariant");
 assert(self->thread_state() != _thread_blocked, "invariant");
 // Possible mark states: neutral, biased, stack-locked, inflated
-if (UseBiasedLocking && h_obj()->mark()->has_bias_pattern()) {
+if (UseBiasedLocking && h_obj()->mark().has_bias_pattern()) {
 // CASE: biased
-BiasedLocking::revoke_and_rebias(h_obj, false, self);
+BiasedLocking::revoke(h_obj, self);
-assert(!h_obj->mark()->has_bias_pattern(),
+assert(!h_obj->mark().has_bias_pattern(),
 "biases should be revoked by now");
 }
 assert(self == JavaThread::current(), "Can only be called on current thread");
 oop obj = h_obj();
-markOop mark = ReadStableMark(obj);
+markWord mark = read_stable_mark(obj);
 // CASE: stack-locked.  Mark points to a BasicLock on the owner's stack.
-if (mark->has_locker()) {
+if (mark.has_locker()) {
-return self->is_lock_owned((address)mark->locker()) ?
+return self->is_lock_owned((address)mark.locker()) ?
 owner_self : owner_other;
 }
 // CASE: inflated. Mark (tagged pointer) points to an ObjectMonitor.
 // The Object:ObjectMonitor relationship is stable as long as we're
 // not at a safepoint.
-if (mark->has_monitor()) {
+if (mark.has_monitor()) {
-void * owner = mark->monitor()->_owner;
+void* owner = mark.monitor()->_owner;
 if (owner == NULL) return owner_none;
 return (owner == self ||
 self->is_lock_owned((address)owner)) ? owner_self : owner_other;
 }
 // CASE: neutral
-assert(mark->is_neutral(), "sanity check");
+assert(mark.is_neutral(), "sanity check");
 return owner_none;           // it's unlocked
 }
 // FIXME: jvmti should call this
 JavaThread* ObjectSynchronizer::get_lock_owner(ThreadsList * t_list, Handle h_obj) {
 if (UseBiasedLocking) {
 if (SafepointSynchronize::is_at_safepoint()) {
 BiasedLocking::revoke_at_safepoint(h_obj);
 } else {
-BiasedLocking::revoke_and_rebias(h_obj, false, JavaThread::current());
+BiasedLocking::revoke(h_obj, JavaThread::current());
 }
-assert(!h_obj->mark()->has_bias_pattern(), "biases should be revoked by now");
+assert(!h_obj->mark().has_bias_pattern(), "biases should be revoked by now");
 }
 oop obj = h_obj();
 address owner = NULL;
-markOop mark = ReadStableMark(obj);
+markWord mark = read_stable_mark(obj);
 // Uncontended case, header points to stack
-if (mark->has_locker()) {
+if (mark.has_locker()) {
-owner = (address) mark->locker();
+owner = (address) mark.locker();
 }
 // Contended case, header points to ObjectMonitor (tagged pointer)
-else if (mark->has_monitor()) {
+else if (mark.has_monitor()) {
-ObjectMonitor* monitor = mark->monitor();
+ObjectMonitor* monitor = mark.monitor();
 assert(monitor != NULL, "monitor should be non-null");
 owner = (address) monitor->owner();
 }
 if (owner != NULL) {
 }
 // Unlocked case, header in place
 // Cannot have assertion since this object may have been
 // locked by another thread when reaching here.
-// assert(mark->is_neutral(), "sanity check");
+// assert(mark.is_neutral(), "sanity check");
 return NULL;
 }
 // Visitors ...
 void ObjectSynchronizer::monitors_iterate(MonitorClosure* closure) {
-PaddedEnd<ObjectMonitor> * block = OrderAccess::load_acquire(&gBlockList);
+PaddedObjectMonitor* block = OrderAccess::load_acquire(&g_block_list);
 while (block != NULL) {
 assert(block->object() == CHAINMARKER, "must be a block header");
 for (int i = _BLOCKSIZE - 1; i > 0; i--) {
 ObjectMonitor* mid = (ObjectMonitor *)(block + i);
 oop object = (oop)mid->object();
 if (object != NULL) {
+// Only process with closure if the object is set.
 closure->do_monitor(mid);
 }
 }
-block = (PaddedEnd<ObjectMonitor> *)block->FreeNext;
+block = (PaddedObjectMonitor*)block->_next_om;
 }
-}
-// Get the next block in the block list.
-static inline PaddedEnd<ObjectMonitor>* next(PaddedEnd<ObjectMonitor>* block) {
-assert(block->object() == CHAINMARKER, "must be a block header");
-block = (PaddedEnd<ObjectMonitor>*) block->FreeNext;
-assert(block == NULL || block->object() == CHAINMARKER, "must be a block header");
-return block;
 }
 static bool monitors_used_above_threshold() {
-if (gMonitorPopulation == 0) {
+if (g_om_population == 0) {
 return false;
 }
-int monitors_used = gMonitorPopulation - gMonitorFreeCount;
+int monitors_used = g_om_population - g_om_free_count;
-int monitor_usage = (monitors_used * 100LL) / gMonitorPopulation;
+int monitor_usage = (monitors_used * 100LL) / g_om_population;
 return monitor_usage > MonitorUsedDeflationThreshold;
 }
 bool ObjectSynchronizer::is_cleanup_needed() {
 if (MonitorUsedDeflationThreshold > 0) {
 global_used_oops_do(f);
 }
 void ObjectSynchronizer::global_used_oops_do(OopClosure* f) {
 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
-list_oops_do(gOmInUseList, f);
+list_oops_do(g_om_in_use_list, f);
 }
 void ObjectSynchronizer::thread_local_used_oops_do(Thread* thread, OopClosure* f) {
 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
-list_oops_do(thread->omInUseList, f);
+list_oops_do(thread->om_in_use_list, f);
 }
 void ObjectSynchronizer::list_oops_do(ObjectMonitor* list, OopClosure* f) {
 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
 ObjectMonitor* mid;
-for (mid = list; mid != NULL; mid = mid->FreeNext) {
+for (mid = list; mid != NULL; mid = mid->_next_om) {
 if (mid->object() != NULL) {
 f->do_oop((oop*)mid->object_addr());
 }
 }
 }
 // -----------------------------------------------------------------------------
 // ObjectMonitor Lifecycle
 // -----------------------
-// Inflation unlinks monitors from the global gFreeList and
+// Inflation unlinks monitors from the global g_free_list and
 // associates them with objects.  Deflation -- which occurs at
 // STW-time -- disassociates idle monitors from objects.  Such
-// scavenged monitors are returned to the gFreeList.
+// scavenged monitors are returned to the g_free_list.
 //
 // The global list is protected by gListLock.  All the critical sections
 // are short and operate in constant-time.
 //
 // ObjectMonitors reside in type-stable memory (TSM) and are immortal.
 //
 // Lifecycle:
 // --   unassigned and on the global free list
-// --   unassigned and on a thread's private omFreeList
+// --   unassigned and on a thread's private om_free_list
 // --   assigned to an object.  The object is inflated and the mark refers
 //      to the objectmonitor.
 // Constraining monitor pool growth via MonitorBound ...
+//
+// If MonitorBound is not set (<= 0), MonitorBound checks are disabled.
 //
 // The monitor pool is grow-only.  We scavenge at STW safepoint-time, but the
 // the rate of scavenging is driven primarily by GC.  As such,  we can find
 // an inordinate number of monitors in circulation.
 // To avoid that scenario we can artificially induce a STW safepoint
 // we could just loop. In addition, if MonitorBound is set to a low value
 // we'll incur more safepoints, which are harmful to performance.
 // See also: GuaranteedSafepointInterval
 //
 // The current implementation uses asynchronous VM operations.
+//
-static void InduceScavenge(Thread * Self, const char * Whence) {
+// If MonitorBound is set, the boundry applies to
+//     (g_om_population - g_om_free_count)
+// i.e., if there are not enough ObjectMonitors on the global free list,
+// then a safepoint deflation is induced. Picking a good MonitorBound value
+// is non-trivial.
+static void InduceScavenge(Thread* self, const char * Whence) {
 // Induce STW safepoint to trim monitors
 // Ultimately, this results in a call to deflate_idle_monitors() in the near future.
 // More precisely, trigger an asynchronous STW safepoint as the number
 // of active monitors passes the specified threshold.
 // TODO: assert thread state is reasonable
 // The VMThread will delete the op when completed.
 VMThread::execute(new VM_ScavengeMonitors());
 }
 }
-ObjectMonitor* ObjectSynchronizer::omAlloc(Thread * Self) {
+ObjectMonitor* ObjectSynchronizer::om_alloc(Thread* self) {
 // A large MAXPRIVATE value reduces both list lock contention
 // and list coherency traffic, but also tends to increase the
-// number of objectMonitors in circulation as well as the STW
+// number of ObjectMonitors in circulation as well as the STW
 // scavenge costs.  As usual, we lean toward time in space-time
 // tradeoffs.
 const int MAXPRIVATE = 1024;
+stringStream ss;
 for (;;) {
-ObjectMonitor * m;
+ObjectMonitor* m;
-// 1: try to allocate from the thread's local omFreeList.
+// 1: try to allocate from the thread's local om_free_list.
 // Threads will attempt to allocate first from their local list, then
 // from the global list, and only after those attempts fail will the thread
 // attempt to instantiate new monitors.   Thread-local free lists take
 // heat off the gListLock and improve allocation latency, as well as reducing
 // coherency traffic on the shared global list.
-m = Self->omFreeList;
+m = self->om_free_list;
 if (m != NULL) {
-Self->omFreeList = m->FreeNext;
+self->om_free_list = m->_next_om;
-Self->omFreeCount--;
+self->om_free_count--;
 guarantee(m->object() == NULL, "invariant");
-m->FreeNext = Self->omInUseList;
+m->_next_om = self->om_in_use_list;
-Self->omInUseList = m;
+self->om_in_use_list = m;
-Self->omInUseCount++;
+self->om_in_use_count++;
 return m;
 }
-// 2: try to allocate from the global gFreeList
+// 2: try to allocate from the global g_free_list
 // CONSIDER: use muxTry() instead of muxAcquire().
 // If the muxTry() fails then drop immediately into case 3.
 // If we're using thread-local free lists then try
 // to reprovision the caller's free list.
-if (gFreeList != NULL) {
+if (g_free_list != NULL) {
-// Reprovision the thread's omFreeList.
+// Reprovision the thread's om_free_list.
 // Use bulk transfers to reduce the allocation rate and heat
 // on various locks.
-Thread::muxAcquire(&gListLock, "omAlloc(1)");
+Thread::muxAcquire(&gListLock, "om_alloc(1)");
-for (int i = Self->omFreeProvision; --i >= 0 && gFreeList != NULL;) {
+for (int i = self->om_free_provision; --i >= 0 && g_free_list != NULL;) {
-gMonitorFreeCount--;
+g_om_free_count--;
-ObjectMonitor * take = gFreeList;
+ObjectMonitor* take = g_free_list;
-gFreeList = take->FreeNext;
+g_free_list = take->_next_om;
 guarantee(take->object() == NULL, "invariant");
-guarantee(!take->is_busy(), "invariant");
 take->Recycle();
-omRelease(Self, take, false);
+om_release(self, take, false);
 }
 Thread::muxRelease(&gListLock);
-Self->omFreeProvision += 1 + (Self->omFreeProvision/2);
+self->om_free_provision += 1 + (self->om_free_provision/2);
-if (Self->omFreeProvision > MAXPRIVATE) Self->omFreeProvision = MAXPRIVATE;
+if (self->om_free_provision > MAXPRIVATE) self->om_free_provision = MAXPRIVATE;
 const int mx = MonitorBound;
-if (mx > 0 && (gMonitorPopulation-gMonitorFreeCount) > mx) {
+if (mx > 0 && (g_om_population-g_om_free_count) > mx) {
-// We can't safely induce a STW safepoint from omAlloc() as our thread
+// Not enough ObjectMonitors on the global free list.
+// We can't safely induce a STW safepoint from om_alloc() as our thread
 // state may not be appropriate for such activities and callers may hold
 // naked oops, so instead we defer the action.
-InduceScavenge(Self, "omAlloc");
+InduceScavenge(self, "om_alloc");
 }
 continue;
 }
 // 3: allocate a block of new ObjectMonitors
 // Both the local and global free lists are empty -- resort to malloc().
-// In the current implementation objectMonitors are TSM - immortal.
+// In the current implementation ObjectMonitors are TSM - immortal.
 // Ideally, we'd write "new ObjectMonitor[_BLOCKSIZE], but we want
 // each ObjectMonitor to start at the beginning of a cache line,
 // so we use align_up().
 // A better solution would be to use C++ placement-new.
 // BEWARE: As it stands currently, we don't run the ctors!
 assert(_BLOCKSIZE > 1, "invariant");
-size_t neededsize = sizeof(PaddedEnd<ObjectMonitor>) * _BLOCKSIZE;
+size_t neededsize = sizeof(PaddedObjectMonitor) * _BLOCKSIZE;
-PaddedEnd<ObjectMonitor> * temp;
+PaddedObjectMonitor* temp;
 size_t aligned_size = neededsize + (DEFAULT_CACHE_LINE_SIZE - 1);
-void* real_malloc_addr = (void *)NEW_C_HEAP_ARRAY(char, aligned_size,
+void* real_malloc_addr = NEW_C_HEAP_ARRAY(char, aligned_size, mtInternal);
-mtInternal);
+temp = (PaddedObjectMonitor*)align_up(real_malloc_addr, DEFAULT_CACHE_LINE_SIZE);
-temp = (PaddedEnd<ObjectMonitor> *)
-align_up(real_malloc_addr, DEFAULT_CACHE_LINE_SIZE);
-// NOTE: (almost) no way to recover if allocation failed.
-// We might be able to induce a STW safepoint and scavenge enough
-// objectMonitors to permit progress.
-if (temp == NULL) {
-vm_exit_out_of_memory(neededsize, OOM_MALLOC_ERROR,
-"Allocate ObjectMonitors");
-}
 (void)memset((void *) temp, 0, neededsize);
 // Format the block.
 // initialize the linked list, each monitor points to its next
 // forming the single linked free list, the very first monitor
 // will points to next block, which forms the block list.
-// The trick of using the 1st element in the block as gBlockList
+// The trick of using the 1st element in the block as g_block_list
 // linkage should be reconsidered.  A better implementation would
 // look like: class Block { Block * next; int N; ObjectMonitor Body [N] ; }
 for (int i = 1; i < _BLOCKSIZE; i++) {
-temp[i].FreeNext = (ObjectMonitor *)&temp[i+1];
+temp[i]._next_om = (ObjectMonitor *)&temp[i+1];
 }
 // terminate the last monitor as the end of list
-temp[_BLOCKSIZE - 1].FreeNext = NULL;
+temp[_BLOCKSIZE - 1]._next_om = NULL;
 // Element [0] is reserved for global list linkage
 temp[0].set_object(CHAINMARKER);
 // Consider carving out this thread's current request from the
 // block in hand.  This avoids some lock traffic and redundant
 // list activity.
-// Acquire the gListLock to manipulate gBlockList and gFreeList.
+// Acquire the gListLock to manipulate g_block_list and g_free_list.
 // An Oyama-Taura-Yonezawa scheme might be more efficient.
-Thread::muxAcquire(&gListLock, "omAlloc(2)");
+Thread::muxAcquire(&gListLock, "om_alloc(2)");
-gMonitorPopulation += _BLOCKSIZE-1;
+g_om_population += _BLOCKSIZE-1;
-gMonitorFreeCount += _BLOCKSIZE-1;
+g_om_free_count += _BLOCKSIZE-1;
-// Add the new block to the list of extant blocks (gBlockList).
+// Add the new block to the list of extant blocks (g_block_list).
-// The very first objectMonitor in a block is reserved and dedicated.
+// The very first ObjectMonitor in a block is reserved and dedicated.
 // It serves as blocklist "next" linkage.
-temp[0].FreeNext = gBlockList;
+temp[0]._next_om = g_block_list;
-// There are lock-free uses of gBlockList so make sure that
+// There are lock-free uses of g_block_list so make sure that
-// the previous stores happen before we update gBlockList.
+// the previous stores happen before we update g_block_list.
-OrderAccess::release_store(&gBlockList, temp);
+OrderAccess::release_store(&g_block_list, temp);
-// Add the new string of objectMonitors to the global free list
+// Add the new string of ObjectMonitors to the global free list
-temp[_BLOCKSIZE - 1].FreeNext = gFreeList;
+temp[_BLOCKSIZE - 1]._next_om = g_free_list;
-gFreeList = temp + 1;
+g_free_list = temp + 1;
 Thread::muxRelease(&gListLock);
 }
 }
-// Place "m" on the caller's private per-thread omFreeList.
+// Place "m" on the caller's private per-thread om_free_list.
 // In practice there's no need to clamp or limit the number of
-// monitors on a thread's omFreeList as the only time we'll call
+// monitors on a thread's om_free_list as the only non-allocation time
-// omRelease is to return a monitor to the free list after a CAS
+// we'll call om_release() is to return a monitor to the free list after
-// attempt failed.  This doesn't allow unbounded #s of monitors to
+// a CAS attempt failed. This doesn't allow unbounded #s of monitors to
 // accumulate on a thread's free list.
 //
 // Key constraint: all ObjectMonitors on a thread's free list and the global
 // free list must have their object field set to null. This prevents the
-// scavenger -- deflate_monitor_list() -- from reclaiming them.
+// scavenger -- deflate_monitor_list() -- from reclaiming them while we
+// are trying to release them.
-void ObjectSynchronizer::omRelease(Thread * Self, ObjectMonitor * m,
-bool fromPerThreadAlloc) {
+void ObjectSynchronizer::om_release(Thread* self, ObjectMonitor* m,
-guarantee(m->header() == NULL, "invariant");
+bool from_per_thread_alloc) {
+guarantee(m->header().value() == 0, "invariant");
 guarantee(m->object() == NULL, "invariant");
-guarantee(((m->is_busy()|m->_recursions) == 0), "freeing in-use monitor");
+stringStream ss;
-// Remove from omInUseList
+guarantee((m->is_busy() | m->_recursions) == 0, "freeing in-use monitor: "
-if (fromPerThreadAlloc) {
+"%s, recursions=" INTPTR_FORMAT, m->is_busy_to_string(&ss),
+m->_recursions);
+// _next_om is used for both per-thread in-use and free lists so
+// we have to remove 'm' from the in-use list first (as needed).
+if (from_per_thread_alloc) {
+// Need to remove 'm' from om_in_use_list.
 ObjectMonitor* cur_mid_in_use = NULL;
 bool extracted = false;
-for (ObjectMonitor* mid = Self->omInUseList; mid != NULL; cur_mid_in_use = mid, mid = mid->FreeNext) {
+for (ObjectMonitor* mid = self->om_in_use_list; mid != NULL; cur_mid_in_use = mid, mid = mid->_next_om) {
 if (m == mid) {
 // extract from per-thread in-use list
-if (mid == Self->omInUseList) {
+if (mid == self->om_in_use_list) {
-Self->omInUseList = mid->FreeNext;
+self->om_in_use_list = mid->_next_om;
 } else if (cur_mid_in_use != NULL) {
-cur_mid_in_use->FreeNext = mid->FreeNext; // maintain the current thread in-use list
+cur_mid_in_use->_next_om = mid->_next_om; // maintain the current thread in-use list
 }
 extracted = true;
-Self->omInUseCount--;
+self->om_in_use_count--;
 break;
 }
 }
 assert(extracted, "Should have extracted from in-use list");
 }
-// FreeNext is used for both omInUseList and omFreeList, so clear old before setting new
+m->_next_om = self->om_free_list;
-m->FreeNext = Self->omFreeList;
+self->om_free_list = m;
-Self->omFreeList = m;
+self->om_free_count++;
-Self->omFreeCount++;
+}
-}
+// Return ObjectMonitors on a moribund thread's free and in-use
-// Return the monitors of a moribund thread's local free list to
+// lists to the appropriate global lists. The ObjectMonitors on the
-// the global free list.  Typically a thread calls omFlush() when
+// per-thread in-use list may still be in use by other threads.
-// it's dying.  We could also consider having the VM thread steal
-// monitors from threads that have not run java code over a few
-// consecutive STW safepoints.  Relatedly, we might decay
-// omFreeProvision at STW safepoints.
 //
-// Also return the monitors of a moribund thread's omInUseList to
+// We currently call om_flush() from Threads::remove() before the
-// a global gOmInUseList under the global list lock so these
+// thread has been excised from the thread list and is no longer a
-// will continue to be scanned.
+// mutator. This means that om_flush() cannot run concurrently with
-//
+// a safepoint and interleave with deflate_idle_monitors(). In
-// We currently call omFlush() from Threads::remove() _before the thread
+// particular, this ensures that the thread's in-use monitors are
-// has been excised from the thread list and is no longer a mutator.
+// scanned by a GC safepoint, either via Thread::oops_do() (before
-// This means that omFlush() cannot run concurrently with a safepoint and
+// om_flush() is called) or via ObjectSynchronizer::oops_do() (after
-// interleave with the deflate_idle_monitors scavenge operator. In particular,
+// om_flush() is called).
-// this ensures that the thread's monitors are scanned by a GC safepoint,
-// either via Thread::oops_do() (if safepoint happens before omFlush()) or via
+void ObjectSynchronizer::om_flush(Thread* self) {
-// ObjectSynchronizer::oops_do() (if it happens after omFlush() and the thread's
+ObjectMonitor* free_list = self->om_free_list;
-// monitors have been transferred to the global in-use list).
+ObjectMonitor* free_tail = NULL;
+int free_count = 0;
-void ObjectSynchronizer::omFlush(Thread * Self) {
+if (free_list != NULL) {
-ObjectMonitor * list = Self->omFreeList;  // Null-terminated SLL
+ObjectMonitor* s;
-ObjectMonitor * tail = NULL;
+// The thread is going away. Set 'free_tail' to the last per-thread free
-int tally = 0;
+// monitor which will be linked to g_free_list below under the gListLock.
-if (list != NULL) {
+stringStream ss;
-ObjectMonitor * s;
+for (s = free_list; s != NULL; s = s->_next_om) {
-// The thread is going away, the per-thread free monitors
+free_count++;
-// are freed via set_owner(NULL)
+free_tail = s;
-// Link them to tail, which will be linked into the global free list
-// gFreeList below, under the gListLock
-for (s = list; s != NULL; s = s->FreeNext) {
-tally++;
-tail = s;
 guarantee(s->object() == NULL, "invariant");
-guarantee(!s->is_busy(), "invariant");
+guarantee(!s->is_busy(), "must be !is_busy: %s", s->is_busy_to_string(&ss));
-s->set_owner(NULL);   // redundant but good hygiene
+}
-}
+guarantee(free_tail != NULL, "invariant");
-guarantee(tail != NULL, "invariant");
+assert(self->om_free_count == free_count, "free-count off");
-assert(Self->omFreeCount == tally, "free-count off");
+self->om_free_list = NULL;
-Self->omFreeList = NULL;
+self->om_free_count = 0;
-Self->omFreeCount = 0;
+}
-}
+ObjectMonitor* in_use_list = self->om_in_use_list;
-ObjectMonitor * inUseList = Self->omInUseList;
+ObjectMonitor* in_use_tail = NULL;
-ObjectMonitor * inUseTail = NULL;
+int in_use_count = 0;
-int inUseTally = 0;
+if (in_use_list != NULL) {
-if (inUseList != NULL) {
+// The thread is going away, however the ObjectMonitors on the
+// om_in_use_list may still be in-use by other threads. Link
+// them to in_use_tail, which will be linked into the global
+// in-use list g_om_in_use_list below, under the gListLock.
 ObjectMonitor *cur_om;
-// The thread is going away, however the omInUseList inflated
+for (cur_om = in_use_list; cur_om != NULL; cur_om = cur_om->_next_om) {
-// monitors may still be in-use by other threads.
+in_use_tail = cur_om;
-// Link them to inUseTail, which will be linked into the global in-use list
+in_use_count++;
-// gOmInUseList below, under the gListLock
+}
-for (cur_om = inUseList; cur_om != NULL; cur_om = cur_om->FreeNext) {
+guarantee(in_use_tail != NULL, "invariant");
-inUseTail = cur_om;
+assert(self->om_in_use_count == in_use_count, "in-use count off");
-inUseTally++;
+self->om_in_use_list = NULL;
-}
+self->om_in_use_count = 0;
-guarantee(inUseTail != NULL, "invariant");
+}
-assert(Self->omInUseCount == inUseTally, "in-use count off");
-Self->omInUseList = NULL;
+Thread::muxAcquire(&gListLock, "om_flush");
-Self->omInUseCount = 0;
+if (free_tail != NULL) {
-}
+free_tail->_next_om = g_free_list;
+g_free_list = free_list;
-Thread::muxAcquire(&gListLock, "omFlush");
+g_om_free_count += free_count;
-if (tail != NULL) {
+}
-tail->FreeNext = gFreeList;
-gFreeList = list;
+if (in_use_tail != NULL) {
-gMonitorFreeCount += tally;
+in_use_tail->_next_om = g_om_in_use_list;
-}
+g_om_in_use_list = in_use_list;
+g_om_in_use_count += in_use_count;
-if (inUseTail != NULL) {
-inUseTail->FreeNext = gOmInUseList;
-gOmInUseList = inUseList;
-gOmInUseCount += inUseTally;
 }
 Thread::muxRelease(&gListLock);
 LogStreamHandle(Debug, monitorinflation) lsh_debug;
 LogStreamHandle(Info, monitorinflation) lsh_info;
-LogStream * ls = NULL;
+LogStream* ls = NULL;
 if (log_is_enabled(Debug, monitorinflation)) {
 ls = &lsh_debug;
-} else if ((tally != 0 || inUseTally != 0) &&
+} else if ((free_count != 0 || in_use_count != 0) &&
 log_is_enabled(Info, monitorinflation)) {
 ls = &lsh_info;
 }
 if (ls != NULL) {
-ls->print_cr("omFlush: jt=" INTPTR_FORMAT ", free_monitor_tally=%d"
+ls->print_cr("om_flush: jt=" INTPTR_FORMAT ", free_count=%d"
-", in_use_monitor_tally=%d" ", omFreeProvision=%d",
+", in_use_count=%d" ", om_free_provision=%d",
-p2i(Self), tally, inUseTally, Self->omFreeProvision);
+p2i(self), free_count, in_use_count, self->om_free_provision);
 }
 }
 static void post_monitor_inflate_event(EventJavaMonitorInflate* event,
 const oop obj,
 event->commit();
 }
 // Fast path code shared by multiple functions
 void ObjectSynchronizer::inflate_helper(oop obj) {
-markOop mark = obj->mark();
+markWord mark = obj->mark();
-if (mark->has_monitor()) {
+if (mark.has_monitor()) {
-assert(ObjectSynchronizer::verify_objmon_isinpool(mark->monitor()), "monitor is invalid");
+assert(ObjectSynchronizer::verify_objmon_isinpool(mark.monitor()), "monitor is invalid");
-assert(mark->monitor()->header()->is_neutral(), "monitor must record a good object header");
+assert(mark.monitor()->header().is_neutral(), "monitor must record a good object header");
 return;
 }
 inflate(Thread::current(), obj, inflate_cause_vm_internal);
 }
-ObjectMonitor* ObjectSynchronizer::inflate(Thread * Self,
+ObjectMonitor* ObjectSynchronizer::inflate(Thread* self,
 oop object,
 const InflateCause cause) {
 // Inflate mutates the heap ...
 // Relaxing assertion for bug 6320749.
 assert(Universe::verify_in_progress() ||
 !SafepointSynchronize::is_at_safepoint(), "invariant");
 EventJavaMonitorInflate event;
 for (;;) {
-const markOop mark = object->mark();
+const markWord mark = object->mark();
-assert(!mark->has_bias_pattern(), "invariant");
+assert(!mark.has_bias_pattern(), "invariant");
 // The mark can be in one of the following states:
 // *  Inflated     - just return
 // *  Stack-locked - coerce it to inflated
 // *  INFLATING    - busy wait for conversion to complete
 // *  Neutral      - aggressively inflate the object.
 // *  BIASED       - Illegal.  We should never see this
 // CASE: inflated
-if (mark->has_monitor()) {
+if (mark.has_monitor()) {
-ObjectMonitor * inf = mark->monitor();
+ObjectMonitor* inf = mark.monitor();
-markOop dmw = inf->header();
+markWord dmw = inf->header();
-assert(dmw->is_neutral(), "invariant: header=" INTPTR_FORMAT, p2i(dmw));
+assert(dmw.is_neutral(), "invariant: header=" INTPTR_FORMAT, dmw.value());
-assert(oopDesc::equals((oop) inf->object(), object), "invariant");
+assert(inf->object() == object, "invariant");
 assert(ObjectSynchronizer::verify_objmon_isinpool(inf), "monitor is invalid");
 return inf;
 }
 // CASE: inflation in progress - inflating over a stack-lock.
 // Some other thread is converting from stack-locked to inflated.
 // Only that thread can complete inflation -- other threads must wait.
 // The INFLATING value is transient.
 // Currently, we spin/yield/park and poll the markword, waiting for inflation to finish.
 // We could always eliminate polling by parking the thread on some auxiliary list.
-if (mark == markOopDesc::INFLATING()) {
+if (mark == markWord::INFLATING()) {
-ReadStableMark(object);
+read_stable_mark(object);
 continue;
 }
 // CASE: stack-locked
 // Could be stack-locked either by this thread or by some other thread.
 // We now use per-thread private objectmonitor free lists.
 // These list are reprovisioned from the global free list outside the
 // critical INFLATING...ST interval.  A thread can transfer
 // multiple objectmonitors en-mass from the global free list to its local free list.
 // This reduces coherency traffic and lock contention on the global free list.
-// Using such local free lists, it doesn't matter if the omAlloc() call appears
+// Using such local free lists, it doesn't matter if the om_alloc() call appears
 // before or after the CAS(INFLATING) operation.
-// See the comments in omAlloc().
+// See the comments in om_alloc().
 LogStreamHandle(Trace, monitorinflation) lsh;
-if (mark->has_locker()) {
+if (mark.has_locker()) {
-ObjectMonitor * m = omAlloc(Self);
+ObjectMonitor* m = om_alloc(self);
 // Optimistically prepare the objectmonitor - anticipate successful CAS
 // We do this before the CAS in order to minimize the length of time
 // in which INFLATING appears in the mark.
 m->Recycle();
 m->_Responsible  = NULL;
-m->_recursions   = 0;
 m->_SpinDuration = ObjectMonitor::Knob_SpinLimit;   // Consider: maintain by type/class
-markOop cmp = object->cas_set_mark(markOopDesc::INFLATING(), mark);
+markWord cmp = object->cas_set_mark(markWord::INFLATING(), mark);
 if (cmp != mark) {
-omRelease(Self, m, true);
+om_release(self, m, true);
 continue;       // Interference -- just retry
 }
 // We've successfully installed INFLATING (0) into the mark-word.
 // This is the only case where 0 will appear in a mark-word.
 //
 // Why do we CAS a 0 into the mark-word instead of just CASing the
 // mark-word from the stack-locked value directly to the new inflated state?
 // Consider what happens when a thread unlocks a stack-locked object.
 // It attempts to use CAS to swing the displaced header value from the
-// on-stack basiclock back into the object header.  Recall also that the
+// on-stack BasicLock back into the object header.  Recall also that the
 // header value (hash code, etc) can reside in (a) the object header, or
 // (b) a displaced header associated with the stack-lock, or (c) a displaced
-// header in an objectMonitor.  The inflate() routine must copy the header
+// header in an ObjectMonitor.  The inflate() routine must copy the header
-// value from the basiclock on the owner's stack to the objectMonitor, all
+// value from the BasicLock on the owner's stack to the ObjectMonitor, all
 // the while preserving the hashCode stability invariants.  If the owner
 // decides to release the lock while the value is 0, the unlock will fail
 // and control will eventually pass from slow_exit() to inflate.  The owner
 // will then spin, waiting for the 0 value to disappear.   Put another way,
 // the 0 causes the owner to stall if the owner happens to try to
-// drop the lock (restoring the header from the basiclock to the object)
+// drop the lock (restoring the header from the BasicLock to the object)
 // while inflation is in-progress.  This protocol avoids races that might
 // would otherwise permit hashCode values to change or "flicker" for an object.
-// Critically, while object->mark is 0 mark->displaced_mark_helper() is stable.
+// Critically, while object->mark is 0 mark.displaced_mark_helper() is stable.
 // 0 serves as a "BUSY" inflate-in-progress indicator.
 // fetch the displaced mark from the owner's stack.
 // The owner can't die or unwind past the lock while our INFLATING
 // object is in the mark.  Furthermore the owner can't complete
 // an unlock on the object, either.
-markOop dmw = mark->displaced_mark_helper();
+markWord dmw = mark.displaced_mark_helper();
 // Catch if the object's header is not neutral (not locked and
 // not marked is what we care about here).
-assert(dmw->is_neutral(), "invariant: header=" INTPTR_FORMAT, p2i(dmw));
+assert(dmw.is_neutral(), "invariant: header=" INTPTR_FORMAT, dmw.value());
 // Setup monitor fields to proper values -- prepare the monitor
 m->set_header(dmw);
-// Optimization: if the mark->locker stack address is associated
+// Optimization: if the mark.locker stack address is associated
-// with this thread we could simply set m->_owner = Self.
+// with this thread we could simply set m->_owner = self.
 // Note that a thread can inflate an object
 // that it has stack-locked -- as might happen in wait() -- directly
 // with CAS.  That is, we can avoid the xchg-NULL .... ST idiom.
-m->set_owner(mark->locker());
+m->set_owner(mark.locker());
 m->set_object(object);
 // TODO-FIXME: assert BasicLock->dhw != 0.
 // Must preserve store ordering. The monitor state must
 // be stable at the time of publishing the monitor address.
-guarantee(object->mark() == markOopDesc::INFLATING(), "invariant");
+guarantee(object->mark() == markWord::INFLATING(), "invariant");
-object->release_set_mark(markOopDesc::encode(m));
+object->release_set_mark(markWord::encode(m));
 // Hopefully the performance counters are allocated on distinct cache lines
 // to avoid false sharing on MP systems ...
 OM_PERFDATA_OP(Inflations, inc());
 if (log_is_enabled(Trace, monitorinflation)) {
-ResourceMark rm(Self);
+ResourceMark rm(self);
 lsh.print_cr("inflate(has_locker): object=" INTPTR_FORMAT ", mark="
 INTPTR_FORMAT ", type='%s'", p2i(object),
-p2i(object->mark()), object->klass()->external_name());
+object->mark().value(), object->klass()->external_name());
 }
 if (event.should_commit()) {
 post_monitor_inflate_event(&event, object, cause);
 }
 return m;
 }
 // CASE: neutral
 // TODO-FIXME: for entry we currently inflate and then try to CAS _owner.
 // If we know we're inflating for entry it's better to inflate by swinging a
-// pre-locked objectMonitor pointer into the object header.   A successful
+// pre-locked ObjectMonitor pointer into the object header.   A successful
 // CAS inflates the object *and* confers ownership to the inflating thread.
 // In the current implementation we use a 2-step mechanism where we CAS()
-// to inflate and then CAS() again to try to swing _owner from NULL to Self.
+// to inflate and then CAS() again to try to swing _owner from NULL to self.
-// An inflateTry() method that we could call from fast_enter() and slow_enter()
+// An inflateTry() method that we could call from enter() would be useful.
-// would be useful.
 // Catch if the object's header is not neutral (not locked and
 // not marked is what we care about here).
-assert(mark->is_neutral(), "invariant: header=" INTPTR_FORMAT, p2i(mark));
+assert(mark.is_neutral(), "invariant: header=" INTPTR_FORMAT, mark.value());
-ObjectMonitor * m = omAlloc(Self);
+ObjectMonitor* m = om_alloc(self);
 // prepare m for installation - set monitor to initial state
 m->Recycle();
 m->set_header(mark);
-m->set_owner(NULL);
 m->set_object(object);
-m->_recursions   = 0;
 m->_Responsible  = NULL;
 m->_SpinDuration = ObjectMonitor::Knob_SpinLimit;       // consider: keep metastats by type/class
-if (object->cas_set_mark(markOopDesc::encode(m), mark) != mark) {
+if (object->cas_set_mark(markWord::encode(m), mark) != mark) {
-m->set_header(NULL);
+m->set_header(markWord::zero());
 m->set_object(NULL);
 m->Recycle();
-omRelease(Self, m, true);
+om_release(self, m, true);
 m = NULL;
 continue;
 // interference - the markword changed - just retry.
 // The state-transitions are one-way, so there's no chance of
 // live-lock -- "Inflated" is an absorbing state.
 // Hopefully the performance counters are allocated on distinct
 // cache lines to avoid false sharing on MP systems ...
 OM_PERFDATA_OP(Inflations, inc());
 if (log_is_enabled(Trace, monitorinflation)) {
-ResourceMark rm(Self);
+ResourceMark rm(self);
 lsh.print_cr("inflate(neutral): object=" INTPTR_FORMAT ", mark="
 INTPTR_FORMAT ", type='%s'", p2i(object),
-p2i(object->mark()), object->klass()->external_name());
+object->mark().value(), object->klass()->external_name());
 }
 if (event.should_commit()) {
 post_monitor_inflate_event(&event, object, cause);
 }
 return m;
 // We maintain a list of in-use monitors for each thread.
 //
 // deflate_thread_local_monitors() scans a single thread's in-use list, while
 // deflate_idle_monitors() scans only a global list of in-use monitors which
-// is populated only as a thread dies (see omFlush()).
+// is populated only as a thread dies (see om_flush()).
 //
 // These operations are called at all safepoints, immediately after mutators
 // are stopped, but before any objects have moved. Collectively they traverse
 // the population of in-use monitors, deflating where possible. The scavenged
 // monitors are returned to the global monitor free list.
 // This is an unfortunate aspect of this design.
 // Deflate a single monitor if not in-use
 // Return true if deflated, false if in-use
 bool ObjectSynchronizer::deflate_monitor(ObjectMonitor* mid, oop obj,
-ObjectMonitor** freeHeadp,
+ObjectMonitor** free_head_p,
-ObjectMonitor** freeTailp) {
+ObjectMonitor** free_tail_p) {
 bool deflated;
 // Normal case ... The monitor is associated with obj.
-const markOop mark = obj->mark();
+const markWord mark = obj->mark();
-guarantee(mark == markOopDesc::encode(mid), "should match: mark="
+guarantee(mark == markWord::encode(mid), "should match: mark="
-INTPTR_FORMAT ", encoded mid=" INTPTR_FORMAT, p2i(mark),
+INTPTR_FORMAT ", encoded mid=" INTPTR_FORMAT, mark.value(),
-p2i(markOopDesc::encode(mid)));
+markWord::encode(mid).value());
-// Make sure that mark->monitor() and markOopDesc::encode() agree:
+// Make sure that mark.monitor() and markWord::encode() agree:
-guarantee(mark->monitor() == mid, "should match: monitor()=" INTPTR_FORMAT
+guarantee(mark.monitor() == mid, "should match: monitor()=" INTPTR_FORMAT
-", mid=" INTPTR_FORMAT, p2i(mark->monitor()), p2i(mid));
+", mid=" INTPTR_FORMAT, p2i(mark.monitor()), p2i(mid));
-const markOop dmw = mid->header();
+const markWord dmw = mid->header();
-guarantee(dmw->is_neutral(), "invariant: header=" INTPTR_FORMAT, p2i(dmw));
+guarantee(dmw.is_neutral(), "invariant: header=" INTPTR_FORMAT, dmw.value());
 if (mid->is_busy()) {
 deflated = false;
 } else {
 // Deflate the monitor if it is no longer being used
 if (log_is_enabled(Trace, monitorinflation)) {
 ResourceMark rm;
 log_trace(monitorinflation)("deflate_monitor: "
 "object=" INTPTR_FORMAT ", mark="
 INTPTR_FORMAT ", type='%s'", p2i(obj),
-p2i(mark), obj->klass()->external_name());
+mark.value(), obj->klass()->external_name());
 }
 // Restore the header back to obj
 obj->release_set_mark(dmw);
 mid->clear();
 assert(mid->object() == NULL, "invariant: object=" INTPTR_FORMAT,
 p2i(mid->object()));
-// Move the object to the working free list defined by freeHeadp, freeTailp
+// Move the deflated ObjectMonitor to the working free list
-if (*freeHeadp == NULL) *freeHeadp = mid;
+// defined by free_head_p and free_tail_p.
-if (*freeTailp != NULL) {
+if (*free_head_p == NULL) *free_head_p = mid;
-ObjectMonitor * prevtail = *freeTailp;
+if (*free_tail_p != NULL) {
-assert(prevtail->FreeNext == NULL, "cleaned up deflated?");
+// We append to the list so the caller can use mid->_next_om
-prevtail->FreeNext = mid;
+// to fix the linkages in its context.
-}
+ObjectMonitor* prevtail = *free_tail_p;
-*freeTailp = mid;
+// Should have been cleaned up by the caller:
+assert(prevtail->_next_om == NULL, "cleaned up deflated?");
+prevtail->_next_om = mid;
+}
+*free_tail_p = mid;
+// At this point, mid->_next_om still refers to its current
+// value and another ObjectMonitor's _next_om field still
+// refers to this ObjectMonitor. Those linkages have to be
+// cleaned up by the caller who has the complete context.
 deflated = true;
 }
 return deflated;
 }
 // process the same monitor lists concurrently.
 //
 // See also ParallelSPCleanupTask and
 // SafepointSynchronize::do_cleanup_tasks() in safepoint.cpp and
 // Threads::parallel_java_threads_do() in thread.cpp.
-int ObjectSynchronizer::deflate_monitor_list(ObjectMonitor** listHeadp,
+int ObjectSynchronizer::deflate_monitor_list(ObjectMonitor** list_p,
-ObjectMonitor** freeHeadp,
+ObjectMonitor** free_head_p,
-ObjectMonitor** freeTailp) {
+ObjectMonitor** free_tail_p) {
 ObjectMonitor* mid;
 ObjectMonitor* next;
 ObjectMonitor* cur_mid_in_use = NULL;
 int deflated_count = 0;
-for (mid = *listHeadp; mid != NULL;) {
+for (mid = *list_p; mid != NULL;) {
 oop obj = (oop) mid->object();
-if (obj != NULL && deflate_monitor(mid, obj, freeHeadp, freeTailp)) {
+if (obj != NULL && deflate_monitor(mid, obj, free_head_p, free_tail_p)) {
-// if deflate_monitor succeeded,
+// Deflation succeeded and already updated free_head_p and
-// extract from per-thread in-use list
+// free_tail_p as needed. Finish the move to the local free list
-if (mid == *listHeadp) {
+// by unlinking mid from the global or per-thread in-use list.
-*listHeadp = mid->FreeNext;
+if (mid == *list_p) {
+*list_p = mid->_next_om;
 } else if (cur_mid_in_use != NULL) {
-cur_mid_in_use->FreeNext = mid->FreeNext; // maintain the current thread in-use list
+cur_mid_in_use->_next_om = mid->_next_om; // maintain the current thread in-use list
 }
-next = mid->FreeNext;
+next = mid->_next_om;
-mid->FreeNext = NULL;  // This mid is current tail in the freeHeadp list
+mid->_next_om = NULL;  // This mid is current tail in the free_head_p list
 mid = next;
 deflated_count++;
 } else {
 cur_mid_in_use = mid;
-mid = mid->FreeNext;
+mid = mid->_next_om;
 }
 }
 return deflated_count;
 }
 void ObjectSynchronizer::prepare_deflate_idle_monitors(DeflateMonitorCounters* counters) {
-counters->nInuse = 0;              // currently associated with objects
+counters->n_in_use = 0;              // currently associated with objects
-counters->nInCirculation = 0;      // extant
+counters->n_in_circulation = 0;      // extant
-counters->nScavenged = 0;          // reclaimed (global and per-thread)
+counters->n_scavenged = 0;           // reclaimed (global and per-thread)
-counters->perThreadScavenged = 0;  // per-thread scavenge total
+counters->per_thread_scavenged = 0;  // per-thread scavenge total
-counters->perThreadTimes = 0.0;    // per-thread scavenge times
+counters->per_thread_times = 0.0;    // per-thread scavenge times
 }
 void ObjectSynchronizer::deflate_idle_monitors(DeflateMonitorCounters* counters) {
 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
 bool deflated = false;
-ObjectMonitor * freeHeadp = NULL;  // Local SLL of scavenged monitors
+ObjectMonitor* free_head_p = NULL;  // Local SLL of scavenged monitors
-ObjectMonitor * freeTailp = NULL;
+ObjectMonitor* free_tail_p = NULL;
 elapsedTimer timer;
 if (log_is_enabled(Info, monitorinflation)) {
 timer.start();
 }
-// Prevent omFlush from changing mids in Thread dtor's during deflation
+// Prevent om_flush from changing mids in Thread dtor's during deflation
 // And in case the vm thread is acquiring a lock during a safepoint
 // See e.g. 6320749
 Thread::muxAcquire(&gListLock, "deflate_idle_monitors");
 // Note: the thread-local monitors lists get deflated in
 // a separate pass. See deflate_thread_local_monitors().
-// For moribund threads, scan gOmInUseList
+// For moribund threads, scan g_om_in_use_list
 int deflated_count = 0;
-if (gOmInUseList) {
+if (g_om_in_use_list) {
-counters->nInCirculation += gOmInUseCount;
+counters->n_in_circulation += g_om_in_use_count;
-deflated_count = deflate_monitor_list((ObjectMonitor **)&gOmInUseList, &freeHeadp, &freeTailp);
+deflated_count = deflate_monitor_list((ObjectMonitor **)&g_om_in_use_list, &free_head_p, &free_tail_p);
-gOmInUseCount -= deflated_count;
+g_om_in_use_count -= deflated_count;
-counters->nScavenged += deflated_count;
+counters->n_scavenged += deflated_count;
-counters->nInuse += gOmInUseCount;
+counters->n_in_use += g_om_in_use_count;
 }
-// Move the scavenged monitors back to the global free list.
+if (free_head_p != NULL) {
-if (freeHeadp != NULL) {
+// Move the deflated ObjectMonitors back to the global free list.
-guarantee(freeTailp != NULL && counters->nScavenged > 0, "invariant");
+guarantee(free_tail_p != NULL && counters->n_scavenged > 0, "invariant");
-assert(freeTailp->FreeNext == NULL, "invariant");
+assert(free_tail_p->_next_om == NULL, "invariant");
-// constant-time list splice - prepend scavenged segment to gFreeList
+// constant-time list splice - prepend scavenged segment to g_free_list
-freeTailp->FreeNext = gFreeList;
+free_tail_p->_next_om = g_free_list;
-gFreeList = freeHeadp;
+g_free_list = free_head_p;
 }
 Thread::muxRelease(&gListLock);
 timer.stop();
 LogStreamHandle(Debug, monitorinflation) lsh_debug;
 LogStreamHandle(Info, monitorinflation) lsh_info;
-LogStream * ls = NULL;
+LogStream* ls = NULL;
 if (log_is_enabled(Debug, monitorinflation)) {
 ls = &lsh_debug;
 } else if (deflated_count != 0 && log_is_enabled(Info, monitorinflation)) {
 ls = &lsh_info;
 }
 void ObjectSynchronizer::finish_deflate_idle_monitors(DeflateMonitorCounters* counters) {
 // Report the cumulative time for deflating each thread's idle
 // monitors. Note: if the work is split among more than one
 // worker thread, then the reported time will likely be more
 // than a beginning to end measurement of the phase.
-log_info(safepoint, cleanup)("deflating per-thread idle monitors, %3.7f secs, monitors=%d", counters->perThreadTimes, counters->perThreadScavenged);
+log_info(safepoint, cleanup)("deflating per-thread idle monitors, %3.7f secs, monitors=%d", counters->per_thread_times, counters->per_thread_scavenged);
-gMonitorFreeCount += counters->nScavenged;
+g_om_free_count += counters->n_scavenged;
 if (log_is_enabled(Debug, monitorinflation)) {
 // exit_globals()'s call to audit_and_print_stats() is done
 // at the Info level.
 ObjectSynchronizer::audit_and_print_stats(false /* on_exit */);
 } else if (log_is_enabled(Info, monitorinflation)) {
 Thread::muxAcquire(&gListLock, "finish_deflate_idle_monitors");
-log_info(monitorinflation)("gMonitorPopulation=%d, gOmInUseCount=%d, "
+log_info(monitorinflation)("g_om_population=%d, g_om_in_use_count=%d, "
-"gMonitorFreeCount=%d", gMonitorPopulation,
+"g_om_free_count=%d", g_om_population,
-gOmInUseCount, gMonitorFreeCount);
+g_om_in_use_count, g_om_free_count);
 Thread::muxRelease(&gListLock);
 }
 ForceMonitorScavenge = 0;    // Reset
-OM_PERFDATA_OP(Deflations, inc(counters->nScavenged));
+OM_PERFDATA_OP(Deflations, inc(counters->n_scavenged));
-OM_PERFDATA_OP(MonExtant, set_value(counters->nInCirculation));
+OM_PERFDATA_OP(MonExtant, set_value(counters->n_in_circulation));
-GVars.stwRandom = os::random();
+GVars.stw_random = os::random();
-GVars.stwCycle++;
+GVars.stw_cycle++;
 }
 void ObjectSynchronizer::deflate_thread_local_monitors(Thread* thread, DeflateMonitorCounters* counters) {
 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
-ObjectMonitor * freeHeadp = NULL;  // Local SLL of scavenged monitors
+ObjectMonitor* free_head_p = NULL;  // Local SLL of scavenged monitors
-ObjectMonitor * freeTailp = NULL;
+ObjectMonitor* free_tail_p = NULL;
 elapsedTimer timer;
 if (log_is_enabled(Info, safepoint, cleanup) ||
 log_is_enabled(Info, monitorinflation)) {
 timer.start();
 }
-int deflated_count = deflate_monitor_list(thread->omInUseList_addr(), &freeHeadp, &freeTailp);
+int deflated_count = deflate_monitor_list(thread->om_in_use_list_addr(), &free_head_p, &free_tail_p);
 Thread::muxAcquire(&gListLock, "deflate_thread_local_monitors");
 // Adjust counters
-counters->nInCirculation += thread->omInUseCount;
+counters->n_in_circulation += thread->om_in_use_count;
-thread->omInUseCount -= deflated_count;
+thread->om_in_use_count -= deflated_count;
-counters->nScavenged += deflated_count;
+counters->n_scavenged += deflated_count;
-counters->nInuse += thread->omInUseCount;
+counters->n_in_use += thread->om_in_use_count;
-counters->perThreadScavenged += deflated_count;
+counters->per_thread_scavenged += deflated_count;
-// Move the scavenged monitors back to the global free list.
+if (free_head_p != NULL) {
-if (freeHeadp != NULL) {
+// Move the deflated ObjectMonitors back to the global free list.
-guarantee(freeTailp != NULL && deflated_count > 0, "invariant");
+guarantee(free_tail_p != NULL && deflated_count > 0, "invariant");
-assert(freeTailp->FreeNext == NULL, "invariant");
+assert(free_tail_p->_next_om == NULL, "invariant");
-// constant-time list splice - prepend scavenged segment to gFreeList
+// constant-time list splice - prepend scavenged segment to g_free_list
-freeTailp->FreeNext = gFreeList;
+free_tail_p->_next_om = g_free_list;
-gFreeList = freeHeadp;
+g_free_list = free_head_p;
 }
 timer.stop();
-// Safepoint logging cares about cumulative perThreadTimes and
+// Safepoint logging cares about cumulative per_thread_times and
 // we'll capture most of the cost, but not the muxRelease() which
 // should be cheap.
-counters->perThreadTimes += timer.seconds();
+counters->per_thread_times += timer.seconds();
 Thread::muxRelease(&gListLock);
 LogStreamHandle(Debug, monitorinflation) lsh_debug;
 LogStreamHandle(Info, monitorinflation) lsh_info;
-LogStream * ls = NULL;
+LogStream* ls = NULL;
 if (log_is_enabled(Debug, monitorinflation)) {
 ls = &lsh_debug;
 } else if (deflated_count != 0 && log_is_enabled(Info, monitorinflation)) {
 ls = &lsh_info;
 }
 u_char* ObjectSynchronizer::get_gvars_addr() {
 return (u_char*)&GVars;
 }
-u_char* ObjectSynchronizer::get_gvars_hcSequence_addr() {
+u_char* ObjectSynchronizer::get_gvars_hc_sequence_addr() {
-return (u_char*)&GVars.hcSequence;
+return (u_char*)&GVars.hc_sequence;
 }
 size_t ObjectSynchronizer::get_gvars_size() {
 return sizeof(SharedGlobals);
 }
-u_char* ObjectSynchronizer::get_gvars_stwRandom_addr() {
+u_char* ObjectSynchronizer::get_gvars_stw_random_addr() {
-return (u_char*)&GVars.stwRandom;
+return (u_char*)&GVars.stw_random;
 }
 void ObjectSynchronizer::audit_and_print_stats(bool on_exit) {
 assert(on_exit || SafepointSynchronize::is_at_safepoint(), "invariant");
 LogStreamHandle(Debug, monitorinflation) lsh_debug;
 LogStreamHandle(Info, monitorinflation) lsh_info;
 LogStreamHandle(Trace, monitorinflation) lsh_trace;
-LogStream * ls = NULL;
+LogStream* ls = NULL;
 if (log_is_enabled(Trace, monitorinflation)) {
 ls = &lsh_trace;
 } else if (log_is_enabled(Debug, monitorinflation)) {
 ls = &lsh_debug;
 } else if (log_is_enabled(Info, monitorinflation)) {
 // Not at VM exit so grab the global list lock.
 Thread::muxAcquire(&gListLock, "audit_and_print_stats");
 }
 // Log counts for the global and per-thread monitor lists:
-int chkMonitorPopulation = log_monitor_list_counts(ls);
+int chk_om_population = log_monitor_list_counts(ls);
 int error_cnt = 0;
 ls->print_cr("Checking global lists:");
-// Check gMonitorPopulation:
+// Check g_om_population:
-if (gMonitorPopulation == chkMonitorPopulation) {
+if (g_om_population == chk_om_population) {
-ls->print_cr("gMonitorPopulation=%d equals chkMonitorPopulation=%d",
+ls->print_cr("g_om_population=%d equals chk_om_population=%d",
-gMonitorPopulation, chkMonitorPopulation);
+g_om_population, chk_om_population);
 } else {
-ls->print_cr("ERROR: gMonitorPopulation=%d is not equal to "
+ls->print_cr("ERROR: g_om_population=%d is not equal to "
-"chkMonitorPopulation=%d", gMonitorPopulation,
+"chk_om_population=%d", g_om_population,
-chkMonitorPopulation);
+chk_om_population);
 error_cnt++;
 }
-// Check gOmInUseList and gOmInUseCount:
+// Check g_om_in_use_list and g_om_in_use_count:
 chk_global_in_use_list_and_count(ls, &error_cnt);
-// Check gFreeList and gMonitorFreeCount:
+// Check g_free_list and g_om_free_count:
 chk_global_free_list_and_count(ls, &error_cnt);
 if (!on_exit) {
 Thread::muxRelease(&gListLock);
 }
 ls->print_cr("Checking per-thread lists:");
 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *jt = jtiwh.next(); ) {
-// Check omInUseList and omInUseCount:
+// Check om_in_use_list and om_in_use_count:
 chk_per_thread_in_use_list_and_count(jt, ls, &error_cnt);
-// Check omFreeList and omFreeCount:
+// Check om_free_list and om_free_count:
 chk_per_thread_free_list_and_count(jt, ls, &error_cnt);
 }
 if (error_cnt == 0) {
 ls->print_cr("No errors found in monitor list checks.");
 guarantee(error_cnt == 0, "ERROR: found monitor list errors: error_cnt=%d", error_cnt);
 }
 // Check a free monitor entry; log any errors.
-void ObjectSynchronizer::chk_free_entry(JavaThread * jt, ObjectMonitor * n,
+void ObjectSynchronizer::chk_free_entry(JavaThread* jt, ObjectMonitor* n,
 outputStream * out, int *error_cnt_p) {
+stringStream ss;
 if (n->is_busy()) {
 if (jt != NULL) {
 out->print_cr("ERROR: jt=" INTPTR_FORMAT ", monitor=" INTPTR_FORMAT
-": free per-thread monitor must not be busy.", p2i(jt),
+": free per-thread monitor must not be busy: %s", p2i(jt),
-p2i(n));
+p2i(n), n->is_busy_to_string(&ss));
 } else {
 out->print_cr("ERROR: monitor=" INTPTR_FORMAT ": free global monitor "
-"must not be busy.", p2i(n));
+"must not be busy: %s", p2i(n), n->is_busy_to_string(&ss));
 }
 *error_cnt_p = *error_cnt_p + 1;
 }
-if (n->header() != NULL) {
+if (n->header().value() != 0) {
 if (jt != NULL) {
 out->print_cr("ERROR: jt=" INTPTR_FORMAT ", monitor=" INTPTR_FORMAT
 ": free per-thread monitor must have NULL _header "
 "field: _header=" INTPTR_FORMAT, p2i(jt), p2i(n),
-p2i(n->header()));
+n->header().value());
 } else {
 out->print_cr("ERROR: monitor=" INTPTR_FORMAT ": free global monitor "
 "must have NULL _header field: _header=" INTPTR_FORMAT,
-p2i(n), p2i(n->header()));
+p2i(n), n->header().value());
 }
 *error_cnt_p = *error_cnt_p + 1;
 }
 if (n->object() != NULL) {
 if (jt != NULL) {
 }
 // Check the global free list and count; log the results of the checks.
 void ObjectSynchronizer::chk_global_free_list_and_count(outputStream * out,
 int *error_cnt_p) {
-int chkMonitorFreeCount = 0;
+int chk_om_free_count = 0;
-for (ObjectMonitor * n = gFreeList; n != NULL; n = n->FreeNext) {
+for (ObjectMonitor* n = g_free_list; n != NULL; n = n->_next_om) {
 chk_free_entry(NULL /* jt */, n, out, error_cnt_p);
-chkMonitorFreeCount++;
+chk_om_free_count++;
 }
-if (gMonitorFreeCount == chkMonitorFreeCount) {
+if (g_om_free_count == chk_om_free_count) {
-out->print_cr("gMonitorFreeCount=%d equals chkMonitorFreeCount=%d",
+out->print_cr("g_om_free_count=%d equals chk_om_free_count=%d",
-gMonitorFreeCount, chkMonitorFreeCount);
+g_om_free_count, chk_om_free_count);
 } else {
-out->print_cr("ERROR: gMonitorFreeCount=%d is not equal to "
+out->print_cr("ERROR: g_om_free_count=%d is not equal to "
-"chkMonitorFreeCount=%d", gMonitorFreeCount,
+"chk_om_free_count=%d", g_om_free_count,
-chkMonitorFreeCount);
+chk_om_free_count);
 *error_cnt_p = *error_cnt_p + 1;
 }
 }
 // Check the global in-use list and count; log the results of the checks.
 void ObjectSynchronizer::chk_global_in_use_list_and_count(outputStream * out,
 int *error_cnt_p) {
-int chkOmInUseCount = 0;
+int chk_om_in_use_count = 0;
-for (ObjectMonitor * n = gOmInUseList; n != NULL; n = n->FreeNext) {
+for (ObjectMonitor* n = g_om_in_use_list; n != NULL; n = n->_next_om) {
 chk_in_use_entry(NULL /* jt */, n, out, error_cnt_p);
-chkOmInUseCount++;
+chk_om_in_use_count++;
 }
-if (gOmInUseCount == chkOmInUseCount) {
+if (g_om_in_use_count == chk_om_in_use_count) {
-out->print_cr("gOmInUseCount=%d equals chkOmInUseCount=%d", gOmInUseCount,
+out->print_cr("g_om_in_use_count=%d equals chk_om_in_use_count=%d", g_om_in_use_count,
-chkOmInUseCount);
+chk_om_in_use_count);
 } else {
-out->print_cr("ERROR: gOmInUseCount=%d is not equal to chkOmInUseCount=%d",
+out->print_cr("ERROR: g_om_in_use_count=%d is not equal to chk_om_in_use_count=%d",
-gOmInUseCount, chkOmInUseCount);
+g_om_in_use_count, chk_om_in_use_count);
 *error_cnt_p = *error_cnt_p + 1;
 }
 }
 // Check an in-use monitor entry; log any errors.
-void ObjectSynchronizer::chk_in_use_entry(JavaThread * jt, ObjectMonitor * n,
+void ObjectSynchronizer::chk_in_use_entry(JavaThread* jt, ObjectMonitor* n,
 outputStream * out, int *error_cnt_p) {
-if (n->header() == NULL) {
+if (n->header().value() == 0) {
 if (jt != NULL) {
 out->print_cr("ERROR: jt=" INTPTR_FORMAT ", monitor=" INTPTR_FORMAT
 ": in-use per-thread monitor must have non-NULL _header "
 "field.", p2i(jt), p2i(n));
 } else {
 "must have non-NULL _object field.", p2i(n));
 }
 *error_cnt_p = *error_cnt_p + 1;
 }
 const oop obj = (oop)n->object();
-const markOop mark = obj->mark();
+const markWord mark = obj->mark();
-if (!mark->has_monitor()) {
+if (!mark.has_monitor()) {
 if (jt != NULL) {
 out->print_cr("ERROR: jt=" INTPTR_FORMAT ", monitor=" INTPTR_FORMAT
 ": in-use per-thread monitor's object does not think "
 "it has a monitor: obj=" INTPTR_FORMAT ", mark="
-INTPTR_FORMAT,  p2i(jt), p2i(n), p2i(obj), p2i(mark));
+INTPTR_FORMAT,  p2i(jt), p2i(n), p2i(obj), mark.value());
 } else {
 out->print_cr("ERROR: monitor=" INTPTR_FORMAT ": in-use global "
 "monitor's object does not think it has a monitor: obj="
 INTPTR_FORMAT ", mark=" INTPTR_FORMAT, p2i(n),
-p2i(obj), p2i(mark));
+p2i(obj), mark.value());
 }
 *error_cnt_p = *error_cnt_p + 1;
 }
-ObjectMonitor * const obj_mon = mark->monitor();
+ObjectMonitor* const obj_mon = mark.monitor();
 if (n != obj_mon) {
 if (jt != NULL) {
 out->print_cr("ERROR: jt=" INTPTR_FORMAT ", monitor=" INTPTR_FORMAT
 ": in-use per-thread monitor's object does not refer "
 "to the same monitor: obj=" INTPTR_FORMAT ", mark="
 INTPTR_FORMAT ", obj_mon=" INTPTR_FORMAT, p2i(jt),
-p2i(n), p2i(obj), p2i(mark), p2i(obj_mon));
+p2i(n), p2i(obj), mark.value(), p2i(obj_mon));
 } else {
 out->print_cr("ERROR: monitor=" INTPTR_FORMAT ": in-use global "
 "monitor's object does not refer to the same monitor: obj="
 INTPTR_FORMAT ", mark=" INTPTR_FORMAT ", obj_mon="
-INTPTR_FORMAT, p2i(n), p2i(obj), p2i(mark), p2i(obj_mon));
+INTPTR_FORMAT, p2i(n), p2i(obj), mark.value(), p2i(obj_mon));
 }
 *error_cnt_p = *error_cnt_p + 1;
 }
 }
 // Check the thread's free list and count; log the results of the checks.
 void ObjectSynchronizer::chk_per_thread_free_list_and_count(JavaThread *jt,
 outputStream * out,
 int *error_cnt_p) {
-int chkOmFreeCount = 0;
+int chk_om_free_count = 0;
-for (ObjectMonitor * n = jt->omFreeList; n != NULL; n = n->FreeNext) {
+for (ObjectMonitor* n = jt->om_free_list; n != NULL; n = n->_next_om) {
 chk_free_entry(jt, n, out, error_cnt_p);
-chkOmFreeCount++;
+chk_om_free_count++;
 }
-if (jt->omFreeCount == chkOmFreeCount) {
+if (jt->om_free_count == chk_om_free_count) {
-out->print_cr("jt=" INTPTR_FORMAT ": omFreeCount=%d equals "
+out->print_cr("jt=" INTPTR_FORMAT ": om_free_count=%d equals "
-"chkOmFreeCount=%d", p2i(jt), jt->omFreeCount, chkOmFreeCount);
+"chk_om_free_count=%d", p2i(jt), jt->om_free_count, chk_om_free_count);
 } else {
-out->print_cr("ERROR: jt=" INTPTR_FORMAT ": omFreeCount=%d is not "
+out->print_cr("ERROR: jt=" INTPTR_FORMAT ": om_free_count=%d is not "
-"equal to chkOmFreeCount=%d", p2i(jt), jt->omFreeCount,
+"equal to chk_om_free_count=%d", p2i(jt), jt->om_free_count,
-chkOmFreeCount);
+chk_om_free_count);
 *error_cnt_p = *error_cnt_p + 1;
 }
 }
 // Check the thread's in-use list and count; log the results of the checks.
 void ObjectSynchronizer::chk_per_thread_in_use_list_and_count(JavaThread *jt,
 outputStream * out,
 int *error_cnt_p) {
-int chkOmInUseCount = 0;
+int chk_om_in_use_count = 0;
-for (ObjectMonitor * n = jt->omInUseList; n != NULL; n = n->FreeNext) {
+for (ObjectMonitor* n = jt->om_in_use_list; n != NULL; n = n->_next_om) {
 chk_in_use_entry(jt, n, out, error_cnt_p);
-chkOmInUseCount++;
+chk_om_in_use_count++;
 }
-if (jt->omInUseCount == chkOmInUseCount) {
+if (jt->om_in_use_count == chk_om_in_use_count) {
-out->print_cr("jt=" INTPTR_FORMAT ": omInUseCount=%d equals "
+out->print_cr("jt=" INTPTR_FORMAT ": om_in_use_count=%d equals "
-"chkOmInUseCount=%d", p2i(jt), jt->omInUseCount,
+"chk_om_in_use_count=%d", p2i(jt), jt->om_in_use_count,
-chkOmInUseCount);
+chk_om_in_use_count);
 } else {
-out->print_cr("ERROR: jt=" INTPTR_FORMAT ": omInUseCount=%d is not "
+out->print_cr("ERROR: jt=" INTPTR_FORMAT ": om_in_use_count=%d is not "
-"equal to chkOmInUseCount=%d", p2i(jt), jt->omInUseCount,
+"equal to chk_om_in_use_count=%d", p2i(jt), jt->om_in_use_count,
-chkOmInUseCount);
+chk_om_in_use_count);
 *error_cnt_p = *error_cnt_p + 1;
 }
 }
 // Log details about ObjectMonitors on the in-use lists. The 'BHL'
 if (!on_exit) {
 // Not at VM exit so grab the global list lock.
 Thread::muxAcquire(&gListLock, "log_in_use_monitor_details");
 }
-if (gOmInUseCount > 0) {
+stringStream ss;
+if (g_om_in_use_count > 0) {
 out->print_cr("In-use global monitor info:");
 out->print_cr("(B -> is_busy, H -> has hash code, L -> lock status)");
 out->print_cr("%18s  %s  %18s  %18s",
 "monitor", "BHL", "object", "object type");
 out->print_cr("==================  ===  ==================  ==================");
-for (ObjectMonitor * n = gOmInUseList; n != NULL; n = n->FreeNext) {
+for (ObjectMonitor* n = g_om_in_use_list; n != NULL; n = n->_next_om) {
 const oop obj = (oop) n->object();
-const markOop mark = n->header();
+const markWord mark = n->header();
 ResourceMark rm;
-out->print_cr(INTPTR_FORMAT "  %d%d%d  " INTPTR_FORMAT "  %s", p2i(n),
+out->print(INTPTR_FORMAT "  %d%d%d  " INTPTR_FORMAT "  %s", p2i(n),
-n->is_busy() != 0, mark->hash() != 0, n->owner() != NULL,
+n->is_busy() != 0, mark.hash() != 0, n->owner() != NULL,
 p2i(obj), obj->klass()->external_name());
+if (n->is_busy() != 0) {
+out->print(" (%s)", n->is_busy_to_string(&ss));
+ss.reset();
+}
+out->cr();
 }
 }
 if (!on_exit) {
 Thread::muxRelease(&gListLock);
 out->print_cr("(B -> is_busy, H -> has hash code, L -> lock status)");
 out->print_cr("%18s  %18s  %s  %18s  %18s",
 "jt", "monitor", "BHL", "object", "object type");
 out->print_cr("==================  ==================  ===  ==================  ==================");
 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *jt = jtiwh.next(); ) {
-for (ObjectMonitor * n = jt->omInUseList; n != NULL; n = n->FreeNext) {
+for (ObjectMonitor* n = jt->om_in_use_list; n != NULL; n = n->_next_om) {
 const oop obj = (oop) n->object();
-const markOop mark = n->header();
+const markWord mark = n->header();
 ResourceMark rm;
-out->print_cr(INTPTR_FORMAT "  " INTPTR_FORMAT "  %d%d%d  " INTPTR_FORMAT
+out->print(INTPTR_FORMAT "  " INTPTR_FORMAT "  %d%d%d  " INTPTR_FORMAT
 "  %s", p2i(jt), p2i(n), n->is_busy() != 0,
-mark->hash() != 0, n->owner() != NULL, p2i(obj),
+mark.hash() != 0, n->owner() != NULL, p2i(obj),
 obj->klass()->external_name());
+if (n->is_busy() != 0) {
+out->print(" (%s)", n->is_busy_to_string(&ss));
+ss.reset();
+}
+out->cr();
 }
 }
 out->flush();
 }
 // Log counts for the global and per-thread monitor lists and return
 // the population count.
 int ObjectSynchronizer::log_monitor_list_counts(outputStream * out) {
-int popCount = 0;
+int pop_count = 0;
 out->print_cr("%18s  %10s  %10s  %10s",
 "Global Lists:", "InUse", "Free", "Total");
 out->print_cr("==================  ==========  ==========  ==========");
 out->print_cr("%18s  %10d  %10d  %10d", "",
-gOmInUseCount, gMonitorFreeCount, gMonitorPopulation);
+g_om_in_use_count, g_om_free_count, g_om_population);
-popCount += gOmInUseCount + gMonitorFreeCount;
+pop_count += g_om_in_use_count + g_om_free_count;
 out->print_cr("%18s  %10s  %10s  %10s",
 "Per-Thread Lists:", "InUse", "Free", "Provision");
 out->print_cr("==================  ==========  ==========  ==========");
 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *jt = jtiwh.next(); ) {
 out->print_cr(INTPTR_FORMAT "  %10d  %10d  %10d", p2i(jt),
-jt->omInUseCount, jt->omFreeCount, jt->omFreeProvision);
+jt->om_in_use_count, jt->om_free_count, jt->om_free_provision);
-popCount += jt->omInUseCount + jt->omFreeCount;
+pop_count += jt->om_in_use_count + jt->om_free_count;
 }
-return popCount;
+return pop_count;
 }
 #ifndef PRODUCT
 // Check if monitor belongs to the monitor cache
 // The list is grow-only so it's *relatively* safe to traverse
 // the list of extant blocks without taking a lock.
 int ObjectSynchronizer::verify_objmon_isinpool(ObjectMonitor *monitor) {
-PaddedEnd<ObjectMonitor> * block = OrderAccess::load_acquire(&gBlockList);
+PaddedObjectMonitor* block = OrderAccess::load_acquire(&g_block_list);
 while (block != NULL) {
 assert(block->object() == CHAINMARKER, "must be a block header");
 if (monitor > &block[0] && monitor < &block[_BLOCKSIZE]) {
 address mon = (address)monitor;
 address blk = (address)block;
 size_t diff = mon - blk;
-assert((diff % sizeof(PaddedEnd<ObjectMonitor>)) == 0, "must be aligned");
+assert((diff % sizeof(PaddedObjectMonitor)) == 0, "must be aligned");
 return 1;
 }
-block = (PaddedEnd<ObjectMonitor> *)block->FreeNext;
+block = (PaddedObjectMonitor*)block->_next_om;
 }
 return 0;
 }
 #endif

branch	datagramsocketimpl-branch
changeset 58678	9cf78a70fa4f
parent 54786	ebf733a324d4
child 58679	9c3209ff7550