src/hotspot/share/gc/shared/threadLocalAllocBuffer.cpp

rev 48920 : [backport] Use PLAB for evacuations instead of TLAB

*** 52,63 ****
    for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) {
      thread->tlab().accumulate_statistics();
      thread->tlab().initialize_statistics();
    }
  
-   Universe::heap()->accumulate_statistics_all_gclabs();
- 
    // Publish new stats if some allocation occurred.
    if (global_stats()->allocation() != 0) {
      global_stats()->publish();
      global_stats()->print();
    }
--- 52,61 ----
*** 67,77 ****
    Thread* thread = myThread();
    size_t capacity = Universe::heap()->tlab_capacity(thread);
    size_t used     = Universe::heap()->tlab_used(thread);
  
    _gc_waste += (unsigned)remaining();
!   size_t total_allocated = _gclab ? thread->allocated_bytes_gclab() : thread->allocated_bytes();
    size_t allocated_since_last_gc = total_allocated - _allocated_before_last_gc;
    _allocated_before_last_gc = total_allocated;
  
    print_stats("gc");
  
--- 65,75 ----
    Thread* thread = myThread();
    size_t capacity = Universe::heap()->tlab_capacity(thread);
    size_t used     = Universe::heap()->tlab_used(thread);
  
    _gc_waste += (unsigned)remaining();
!   size_t total_allocated = thread->allocated_bytes();
    size_t allocated_since_last_gc = total_allocated - _allocated_before_last_gc;
    _allocated_before_last_gc = total_allocated;
  
    print_stats("gc");
  
*** 112,127 ****
  void ThreadLocalAllocBuffer::make_parsable(bool retire, bool zap) {
    if (end() != NULL) {
      invariants();
  
      if (retire) {
-       if (_gclab) {
-         myThread()->incr_allocated_bytes_gclab(used_bytes());
-       } else {
          myThread()->incr_allocated_bytes(used_bytes());
        }
-     }
  
      HeapWord* obj = Universe::heap()->tlab_post_allocation_setup(top());
      CollectedHeap::fill_with_object(obj, hard_end(), retire && zap);
  
      if (retire || ZeroTLAB) {  // "Reset" the TLAB
--- 110,121 ----
*** 192,204 ****
    set_pf_top(top);
    set_end(end);
    invariants();
  }
  
! void ThreadLocalAllocBuffer::initialize(bool gclab) {
!   _initialized = true;
!   _gclab = gclab;
    initialize(NULL,                    // start
               NULL,                    // top
               NULL);                   // end
  
    set_desired_size(initial_desired_size());
--- 186,196 ----
    set_pf_top(top);
    set_end(end);
    invariants();
  }
  
! void ThreadLocalAllocBuffer::initialize() {
    initialize(NULL,                    // start
               NULL,                    // top
               NULL);                   // end
  
    set_desired_size(initial_desired_size());
*** 251,262 ****
  #endif
  
    // During jvm startup, the main thread is initialized
    // before the heap is initialized.  So reinitialize it now.
    guarantee(Thread::current()->is_Java_thread(), "tlab initialization thread not Java thread");
!   Thread::current()->tlab().initialize(false);
!   Thread::current()->gclab().initialize(true);
  
    log_develop_trace(gc, tlab)("TLAB min: " SIZE_FORMAT " initial: " SIZE_FORMAT " max: " SIZE_FORMAT,
                                 min_size(), Thread::current()->tlab().initial_desired_size(), max_size());
  }
  
--- 243,253 ----
  #endif
  
    // During jvm startup, the main thread is initialized
    // before the heap is initialized.  So reinitialize it now.
    guarantee(Thread::current()->is_Java_thread(), "tlab initialization thread not Java thread");
!   Thread::current()->tlab().initialize();
  
    log_develop_trace(gc, tlab)("TLAB min: " SIZE_FORMAT " initial: " SIZE_FORMAT " max: " SIZE_FORMAT,
                                 min_size(), Thread::current()->tlab().initial_desired_size(), max_size());
  }
  
*** 315,345 ****
    }
    guarantee(p == top(), "end of last object must match end of space");
  }
  
  Thread* ThreadLocalAllocBuffer::myThread() {
!   ByteSize gclab_offset = Thread::gclab_start_offset();
!   ByteSize tlab_offset = Thread::tlab_start_offset();
!   ByteSize offs = _gclab ? gclab_offset : tlab_offset;
!   Thread* thread = (Thread*)(((char *)this) +
!                    in_bytes(start_offset()) - in_bytes(offs));
! #ifdef ASSERT
!   assert(this == (_gclab ? &thread->gclab() : &thread->tlab()), "must be");
! #endif
!   return thread;
! }
! 
! size_t ThreadLocalAllocBuffer::end_reserve() {
!   int reserve_size = typeArrayOopDesc::header_size(T_INT);
!   return MAX2(reserve_size, _reserve_for_allocation_prefetch);
! }
! 
! void ThreadLocalAllocBuffer::rollback(size_t size) {
!   HeapWord* old_top = top();
!   if (old_top != NULL) { // Pathological case: we accept that we can't rollback.
!     set_top(old_top - size);
!   }
  }
  
  
  GlobalTLABStats::GlobalTLABStats() :
    _allocating_threads_avg(TLABAllocationWeight) {
--- 306,318 ----
    }
    guarantee(p == top(), "end of last object must match end of space");
  }
  
  Thread* ThreadLocalAllocBuffer::myThread() {
!   return (Thread*)(((char *)this) +
!                    in_bytes(start_offset()) -
!                    in_bytes(Thread::tlab_start_offset()));
  }
  
  
  GlobalTLABStats::GlobalTLABStats() :
    _allocating_threads_avg(TLABAllocationWeight) {