src/hotspot/share/gc/shenandoah/shenandoahHeapRegion.hpp

rev 57745 : 8240872: Shenandoah: Avoid updating new regions from start of evacuation
Reviewed-by: shade
rev 57746 : 8240873: Shenandoah: Short-cut arraycopy barriers
Reviewed-by: shade

*** 258,268 ****
    uint64_t _seqnum_last_alloc_gc;
  
    volatile size_t _live_data;
    volatile size_t _critical_pins;
  
!   HeapWord* _update_watermark;
  
    // Claim some space at the end to protect next region
    DEFINE_PAD_MINUS_SIZE(0, DEFAULT_CACHE_LINE_SIZE, 0);
  
  public:
--- 258,268 ----
    uint64_t _seqnum_last_alloc_gc;
  
    volatile size_t _live_data;
    volatile size_t _critical_pins;
  
!   HeapWord* volatile _update_watermark;
  
    // Claim some space at the end to protect next region
    DEFINE_PAD_MINUS_SIZE(0, DEFAULT_CACHE_LINE_SIZE, 0);
  
  public:
*** 429,444 ****
      return _seqnum_last_alloc_gc;
    }
  
    HeapWord* get_update_watermark() const {
      assert(bottom() <= _update_watermark && _update_watermark <= top(), "within bounds");
!     return _update_watermark;
    }
  
    void set_update_watermark(HeapWord* w) {
      assert(bottom() <= w && w <= top(), "within bounds");
!     _update_watermark = w;
    }
  
  private:
    void do_commit();
    void do_uncommit();
--- 429,444 ----
      return _seqnum_last_alloc_gc;
    }
  
    HeapWord* get_update_watermark() const {
      assert(bottom() <= _update_watermark && _update_watermark <= top(), "within bounds");
!     return Atomic::load_acquire(&_update_watermark);
    }
  
    void set_update_watermark(HeapWord* w) {
      assert(bottom() <= w && w <= top(), "within bounds");
!     Atomic::release_store(&_update_watermark, w);
    }
  
  private:
    void do_commit();
    void do_uncommit();