src/share/vm/gc/g1/g1YoungRemSetSamplingThread.cpp

rev 10309 : 8150390: Move rs length sampling data to the sampling thread
Reviewed-by:

*** 24,33 ****
--- 24,35 ----
  
  #include "precompiled.hpp"
  #include "gc/g1/g1CollectedHeap.inline.hpp"
  #include "gc/g1/g1CollectorPolicy.hpp"
  #include "gc/g1/g1YoungRemSetSamplingThread.hpp"
+ #include "gc/g1/heapRegion.inline.hpp"
+ #include "gc/g1/heapRegionRemSet.hpp"
  #include "gc/g1/suspendibleThreadSet.hpp"
  #include "runtime/mutexLocker.hpp"
  
  void G1YoungRemSetSamplingThread::run() {
    initialize_in_thread();
*** 98,121 ****
    SuspendibleThreadSetJoiner sts;
    G1CollectedHeap* g1h = G1CollectedHeap::heap();
    G1CollectorPolicy* g1p = g1h->g1_policy();
    if (g1p->adaptive_young_list_length()) {
      int regions_visited = 0;
!     g1h->young_list()->rs_length_sampling_init();
!     while (g1h->young_list()->rs_length_sampling_more()) {
!       g1h->young_list()->rs_length_sampling_next();
        ++regions_visited;
  
        // we try to yield every time we visit 10 regions
        if (regions_visited == 10) {
          if (sts.should_yield()) {
            sts.yield();
!           // we just abandon the iteration
!           break;
          }
          regions_visited = 0;
        }
      }
! 
!     g1p->revise_young_list_target_length_if_necessary();
    }
  }
--- 100,136 ----
    SuspendibleThreadSetJoiner sts;
    G1CollectedHeap* g1h = G1CollectedHeap::heap();
    G1CollectorPolicy* g1p = g1h->g1_policy();
    if (g1p->adaptive_young_list_length()) {
      int regions_visited = 0;
!     HeapRegion* hr = g1h->young_list()->first_region();
!     size_t sampled_rs_lengths = 0;
! 
!     while (hr != NULL) {
!       size_t rs_length = hr->rem_set()->occupied();
!       sampled_rs_lengths += rs_length;
! 
!       // The current region may not yet have been added to the
!       // incremental collection set (it gets added when it is
!       // retired as the current allocation region).
!       if (hr->in_collection_set()) {
!         // Update the collection set policy information for this region
!         g1p->update_incremental_cset_info(hr, rs_length);
!       }
! 
        ++regions_visited;
  
        // we try to yield every time we visit 10 regions
        if (regions_visited == 10) {
          if (sts.should_yield()) {
            sts.yield();
!           // A gc may have occurred and our sampling data is stale and further
!           // traversal of the young list is unsafe
!           return;
          }
          regions_visited = 0;
        }
+       hr = hr->get_next_young_region();
      }
!     g1p->revise_young_list_target_length_if_necessary(sampled_rs_lengths);
    }
  }