archive/jdk
1
0
Fork 0
mirror of https://github.com/openjdk/jdk.git synced 2025-08-27 23:04:50 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

6988353: refactor contended sync subsystem

Browse source 
Reduce complexity by factoring synchronizer.cpp

Reviewed-by: dholmes, never, coleenp
This commit is contained in:
Karen Kinnear 2010-10-22 15:59:34 -04:00
parent daa052114f
commit 22929fb78f
29 changed files with 4556 additions and 4792 deletions
Download patch file Download diff file Expand all files Collapse all files

148
hotspot/src/share/vm/runtime/objectMonitor.hpp
View file

@ -22,6 +22,32 @@
*
*/
// ObjectWaiter serves as a "proxy" or surrogate thread.
// TODO-FIXME: Eliminate ObjectWaiter and use the thread-specific
// ParkEvent instead. Beware, however, that the JVMTI code
// knows about ObjectWaiters, so we'll have to reconcile that code.
// See next_waiter(), first_waiter(), etc.
class ObjectWaiter : public StackObj {
public:
enum TStates { TS_UNDEF, TS_READY, TS_RUN, TS_WAIT, TS_ENTER, TS_CXQ } ;
enum Sorted { PREPEND, APPEND, SORTED } ;
ObjectWaiter * volatile _next;
ObjectWaiter * volatile _prev;
Thread* _thread;
ParkEvent * _event;
volatile int _notified ;
volatile TStates TState ;
Sorted _Sorted ; // List placement disposition
bool _active ; // Contention monitoring is enabled
public:
ObjectWaiter(Thread* thread);
void wait_reenter_begin(ObjectMonitor *mon);
void wait_reenter_end(ObjectMonitor *mon);
};
// WARNING:
// This is a very sensitive and fragile class. DO NOT make any
// change unless you are fully aware of the underlying semantics.
@ -38,8 +64,6 @@
// It is also used as RawMonitor by the JVMTI
class ObjectWaiter;
class ObjectMonitor {
public:
enum {
@ -74,13 +98,16 @@ class ObjectMonitor {
public:
ObjectMonitor();
~ObjectMonitor();
markOop header() const;
void set_header(markOop hdr);
intptr_t is_busy() const;
intptr_t is_busy() const {
// TODO-FIXME: merge _count and _waiters.
// TODO-FIXME: assert _owner == null implies _recursions = 0
// TODO-FIXME: assert _WaitSet != null implies _count > 0
return _count|_waiters|intptr_t(_owner)|intptr_t(_cxq)|intptr_t(_EntryList ) ;
}
intptr_t is_entered(Thread* current) const;
void* owner() const;
@ -91,13 +118,58 @@ class ObjectMonitor {
intptr_t count() const;
void set_count(intptr_t count);
intptr_t contentions() const ;
intptr_t recursions() const { return _recursions; }
// JVM/DI GetMonitorInfo() needs this
Thread * thread_of_waiter (ObjectWaiter *) ;
ObjectWaiter * first_waiter () ;
ObjectWaiter * next_waiter(ObjectWaiter* o);
ObjectWaiter* first_waiter() { return _WaitSet; }
ObjectWaiter* next_waiter(ObjectWaiter* o) { return o->_next; }
Thread* thread_of_waiter(ObjectWaiter* o) { return o->_thread; }
intptr_t recursions() const { return _recursions; }
// initialize the monitor, exception the semaphore, all other fields
// are simple integers or pointers
ObjectMonitor() {
_header = NULL;
_count = 0;
_waiters = 0,
_recursions = 0;
_object = NULL;
_owner = NULL;
_WaitSet = NULL;
_WaitSetLock = 0 ;
_Responsible = NULL ;
_succ = NULL ;
_cxq = NULL ;
FreeNext = NULL ;
_EntryList = NULL ;
_SpinFreq = 0 ;
_SpinClock = 0 ;
OwnerIsThread = 0 ;
}
~ObjectMonitor() {
// TODO: Add asserts ...
// _cxq == 0 _succ == NULL _owner == NULL _waiters == 0
// _count == 0 _EntryList == NULL etc
}
private:
void Recycle () {
// TODO: add stronger asserts ...
// _cxq == 0 _succ == NULL _owner == NULL _waiters == 0
// _count == 0 EntryList == NULL
// _recursions == 0 _WaitSet == NULL
// TODO: assert (is_busy()|_recursions) == 0
_succ = NULL ;
_EntryList = NULL ;
_cxq = NULL ;
_WaitSet = NULL ;
_recursions = 0 ;
_SpinFreq = 0 ;
_SpinClock = 0 ;
OwnerIsThread = 0 ;
}
public:
void* object() const;
void* object_addr();
@ -122,22 +194,9 @@ class ObjectMonitor {
intptr_t complete_exit(TRAPS);
void reenter(intptr_t recursions, TRAPS);
int raw_enter(TRAPS);
int raw_exit(TRAPS);
int raw_wait(jlong millis, bool interruptable, TRAPS);
int raw_notify(TRAPS);
int raw_notifyAll(TRAPS);
private:
// JVMTI support -- remove ASAP
int SimpleEnter (Thread * Self) ;
int SimpleExit (Thread * Self) ;
int SimpleWait (Thread * Self, jlong millis) ;
int SimpleNotify (Thread * Self, bool All) ;
private:
void Recycle () ;
void AddWaiter (ObjectWaiter * waiter) ;
static void DeferredInitialize();
ObjectWaiter * DequeueWaiter () ;
void DequeueSpecificWaiter (ObjectWaiter * waiter) ;
@ -172,13 +231,17 @@ class ObjectMonitor {
// The VM assumes write ordering wrt these fields, which can be
// read from other threads.
protected: // protected for jvmtiRawMonitor
void * volatile _owner; // pointer to owning thread OR BasicLock
volatile intptr_t _recursions; // recursion count, 0 for first entry
private:
int OwnerIsThread ; // _owner is (Thread *) vs SP/BasicLock
ObjectWaiter * volatile _cxq ; // LL of recently-arrived threads blocked on entry.
// The list is actually composed of WaitNodes, acting
// as proxies for Threads.
protected:
ObjectWaiter * volatile _EntryList ; // Threads blocked on entry or reentry.
private:
Thread * volatile _succ ; // Heir presumptive thread - used for futile wakeup throttling
Thread * volatile _Responsible ;
int _PromptDrain ; // rqst to drain cxq into EntryList ASAP
@ -196,8 +259,12 @@ class ObjectMonitor {
volatile intptr_t _count; // reference count to prevent reclaimation/deflation
// at stop-the-world time. See deflate_idle_monitors().
// _count is approximately |_WaitSet| + |_EntryList|
protected:
volatile intptr_t _waiters; // number of waiting threads
private:
protected:
ObjectWaiter * volatile _WaitSet; // LL of threads wait()ing on the monitor
private:
volatile int _WaitSetLock; // protects Wait Queue - simple spinlock
public:
@ -205,4 +272,37 @@ class ObjectMonitor {
ObjectMonitor * FreeNext ; // Free list linkage
intptr_t StatA, StatsB ;
public:
static void Initialize () ;
static PerfCounter * _sync_ContendedLockAttempts ;
static PerfCounter * _sync_FutileWakeups ;
static PerfCounter * _sync_Parks ;
static PerfCounter * _sync_EmptyNotifications ;
static PerfCounter * _sync_Notifications ;
static PerfCounter * _sync_SlowEnter ;
static PerfCounter * _sync_SlowExit ;
static PerfCounter * _sync_SlowNotify ;
static PerfCounter * _sync_SlowNotifyAll ;
static PerfCounter * _sync_FailedSpins ;
static PerfCounter * _sync_SuccessfulSpins ;
static PerfCounter * _sync_PrivateA ;
static PerfCounter * _sync_PrivateB ;
static PerfCounter * _sync_MonInCirculation ;
static PerfCounter * _sync_MonScavenged ;
static PerfCounter * _sync_Inflations ;
static PerfCounter * _sync_Deflations ;
static PerfLongVariable * _sync_MonExtant ;
public:
static int Knob_Verbose;
static int Knob_SpinLimit;
};
#undef TEVENT
#define TEVENT(nom) {if (SyncVerbose) FEVENT(nom); }
#define FEVENT(nom) { static volatile int ctr = 0 ; int v = ++ctr ; if ((v & (v-1)) == 0) { ::printf (#nom " : %d \n", v); ::fflush(stdout); }}
#undef TEVENT
#define TEVENT(nom) {;}