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8332610: Remove unused nWakeups in ObjectMonitor

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Reviewed-by: coleenp, dcubed
This commit is contained in:
Johan Sjölen 2024-05-22 13:52:51 +00:00
parent 92d33501e0
commit 9ca90ccd6b
1 changed files with 5 additions and 9 deletions
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14
src/hotspot/share/runtime/objectMonitor.cpp
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@ -829,7 +829,6 @@ void ObjectMonitor::EnterI(JavaThread* current) {
// to defer the state transitions until absolutely necessary,
// and in doing so avoid some transitions ...
int nWakeups = 0;
int recheckInterval = 1;
for (;;) {
@ -872,15 +871,14 @@ void ObjectMonitor::EnterI(JavaThread* current) {
}
// The lock is still contested.
// Keep a tally of the # of futile wakeups.
// Note that the counter is not protected by a lock or updated by atomics.
// That is by design - we trade "lossy" counters which are exposed to
// races during updates for a lower probe effect.
// This PerfData object can be used in parallel with a safepoint.
// See the work around in PerfDataManager::destroy().
OM_PERFDATA_OP(FutileWakeups, inc());
++nWakeups;
// Assuming this is not a spurious wakeup we'll normally find _succ == current.
// We can defer clearing _succ until after the spin completes
@ -981,7 +979,6 @@ void ObjectMonitor::ReenterI(JavaThread* current, ObjectWaiter* currentNode) {
assert(current->thread_state() != _thread_blocked, "invariant");
int nWakeups = 0;
for (;;) {
ObjectWaiter::TStates v = currentNode->TState;
guarantee(v == ObjectWaiter::TS_ENTER || v == ObjectWaiter::TS_CXQ, "invariant");
@ -1018,11 +1015,6 @@ void ObjectMonitor::ReenterI(JavaThread* current, ObjectWaiter* currentNode) {
}
// The lock is still contested.
// Keep a tally of the # of futile wakeups.
// Note that the counter is not protected by a lock or updated by atomics.
// That is by design - we trade "lossy" counters which are exposed to
// races during updates for a lower probe effect.
++nWakeups;
// Assuming this is not a spurious wakeup we'll normally
// find that _succ == current.
@ -1032,6 +1024,10 @@ void ObjectMonitor::ReenterI(JavaThread* current, ObjectWaiter* currentNode) {
// *must* retry _owner before parking.
OrderAccess::fence();
// Keep a tally of the # of futile wakeups.
// Note that the counter is not protected by a lock or updated by atomics.
// That is by design - we trade "lossy" counters which are exposed to
// races during updates for a lower probe effect.
// This PerfData object can be used in parallel with a safepoint.
// See the work around in PerfDataManager::destroy().
OM_PERFDATA_OP(FutileWakeups, inc());