8231707: Improve Mutex inlining

Reviewed-by: rehn, dholmes, coleenp
This commit is contained in:
Claes Redestad 2019-10-03 13:45:08 +02:00
parent 022c87228b
commit 4084a43111
2 changed files with 20 additions and 12 deletions
src/hotspot/share/runtime

@ -70,22 +70,16 @@ void Mutex::check_no_safepoint_state(Thread* thread) {
}
#endif // ASSERT
void Mutex::lock(Thread* self) {
check_safepoint_state(self);
assert(_owner != self, "invariant");
Mutex* in_flight_mutex = NULL;
void Mutex::lock_contended(Thread* self) {
Mutex *in_flight_mutex = NULL;
DEBUG_ONLY(int retry_cnt = 0;)
bool is_active_Java_thread = self->is_active_Java_thread();
while (!_lock.try_lock()) {
// The lock is contended
#ifdef ASSERT
do {
#ifdef ASSERT
if (retry_cnt++ > 3) {
log_trace(vmmutex)("JavaThread " INTPTR_FORMAT " on %d attempt trying to acquire vmmutex %s", p2i(self), retry_cnt, _name);
}
#endif // ASSERT
#endif // ASSERT
// Is it a JavaThread participating in the safepoint protocol.
if (is_active_Java_thread) {
@ -102,6 +96,17 @@ void Mutex::lock(Thread* self) {
_lock.lock();
break;
}
} while (!_lock.try_lock());
}
void Mutex::lock(Thread* self) {
check_safepoint_state(self);
assert(_owner != self, "invariant");
if (!_lock.try_lock()) {
// The lock is contended, use contended slow-path function to lock
lock_contended(self);
}
assert_owner(NULL);
@ -109,7 +114,7 @@ void Mutex::lock(Thread* self) {
}
void Mutex::lock() {
this->lock(Thread::current());
lock(Thread::current());
}
// Lock without safepoint check - a degenerate variant of lock() for use by

@ -152,6 +152,9 @@ class Mutex : public CHeapObj<mtSynchronizer> {
bool is_locked() const { return _owner != NULL; }
bool try_lock(); // Like lock(), but unblocking. It returns false instead
private:
void lock_contended(Thread *thread); // contended slow-path
public:
void release_for_safepoint();