src/hotspot/share/code/dependencyContext.cpp

 
 PerfCounter* DependencyContext::_perf_total_buckets_allocated_count   = NULL;
 PerfCounter* DependencyContext::_perf_total_buckets_deallocated_count = NULL;
 PerfCounter* DependencyContext::_perf_total_buckets_stale_count       = NULL;
 PerfCounter* DependencyContext::_perf_total_buckets_stale_acc_count   = NULL;
-nmethodBucket* volatile DependencyContext::_purge_list = NULL;
-volatile uint64_t DependencyContext::_cleaning_epoch = 0;
+nmethodBucket* volatile DependencyContext::_purge_list                = NULL;
+volatile uint64_t DependencyContext::_cleaning_epoch                  = 0;
+uint64_t  DependencyContext::_cleaning_epoch_monotonic                = 0;
 
 void dependencyContext_init() {
   DependencyContext::init();
 }
 

@@ -309,11 +310,11
 // After the gc_prologue, the dependency contexts may be claimed by the GC
 // and releasing of nmethodBucket entries will be deferred and placed on
 // a purge list to be deleted later.
 void DependencyContext::cleaning_start() {
   assert(SafepointSynchronize::is_at_safepoint(), "must be");
-  uint64_t epoch = SafepointSynchronize::safepoint_counter();
+  uint64_t epoch = ++_cleaning_epoch_monotonic;
   Atomic::store(epoch, &_cleaning_epoch);
 }
 
 // The epilogue marks the end of dependency context cleanup by the GC,
 // and also makes subsequent releases of nmethodBuckets case immediate