diff -r 4ebc2e2fb97c -r 71c04702a3d5 src/hotspot/share/gc/shared/threadLocalAllocBuffer.hpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/shared/threadLocalAllocBuffer.hpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,266 @@
+/*
+ * Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_VM_GC_SHARED_THREADLOCALALLOCBUFFER_HPP
+#define SHARE_VM_GC_SHARED_THREADLOCALALLOCBUFFER_HPP
+
+#include "gc/shared/gcUtil.hpp"
+#include "oops/typeArrayOop.hpp"
+#include "runtime/perfData.hpp"
+#include "runtime/vm_version.hpp"
+
+class GlobalTLABStats;
+
+// ThreadLocalAllocBuffer: a descriptor for thread-local storage used by
+// the threads for allocation.
+//            It is thread-private at any time, but maybe multiplexed over
+//            time across multiple threads. The park()/unpark() pair is
+//            used to make it available for such multiplexing.
+class ThreadLocalAllocBuffer: public CHeapObj<mtThread> {
+  friend class VMStructs;
+  friend class JVMCIVMStructs;
+private:
+  HeapWord* _start;                              // address of TLAB
+  HeapWord* _top;                                // address after last allocation
+  HeapWord* _pf_top;                             // allocation prefetch watermark
+  HeapWord* _end;                                // allocation end (excluding alignment_reserve)
+  size_t    _desired_size;                       // desired size   (including alignment_reserve)
+  size_t    _refill_waste_limit;                 // hold onto tlab if free() is larger than this
+  size_t    _allocated_before_last_gc;           // total bytes allocated up until the last gc
+
+  static size_t   _max_size;                          // maximum size of any TLAB
+  static int      _reserve_for_allocation_prefetch;   // Reserve at the end of the TLAB
+  static unsigned _target_refills;                    // expected number of refills between GCs
+
+  unsigned  _number_of_refills;
+  unsigned  _fast_refill_waste;
+  unsigned  _slow_refill_waste;
+  unsigned  _gc_waste;
+  unsigned  _slow_allocations;
+
+  AdaptiveWeightedAverage _allocation_fraction;  // fraction of eden allocated in tlabs
+
+  void accumulate_statistics();
+  void initialize_statistics();
+
+  void set_start(HeapWord* start)                { _start = start; }
+  void set_end(HeapWord* end)                    { _end = end; }
+  void set_top(HeapWord* top)                    { _top = top; }
+  void set_pf_top(HeapWord* pf_top)              { _pf_top = pf_top; }
+  void set_desired_size(size_t desired_size)     { _desired_size = desired_size; }
+  void set_refill_waste_limit(size_t waste)      { _refill_waste_limit = waste;  }
+
+  size_t initial_refill_waste_limit()            { return desired_size() / TLABRefillWasteFraction; }
+
+  static int    target_refills()                 { return _target_refills; }
+  size_t initial_desired_size();
+
+  size_t remaining() const                       { return end() == NULL ? 0 : pointer_delta(hard_end(), top()); }
+
+  // Make parsable and release it.
+  void reset();
+
+  // Resize based on amount of allocation, etc.
+  void resize();
+
+  void invariants() const { assert(top() >= start() && top() <= end(), "invalid tlab"); }
+
+  void initialize(HeapWord* start, HeapWord* top, HeapWord* end);
+
+  void print_stats(const char* tag);
+
+  Thread* myThread();
+
+  // statistics
+
+  int number_of_refills() const { return _number_of_refills; }
+  int fast_refill_waste() const { return _fast_refill_waste; }
+  int slow_refill_waste() const { return _slow_refill_waste; }
+  int gc_waste() const          { return _gc_waste; }
+  int slow_allocations() const  { return _slow_allocations; }
+
+  static GlobalTLABStats* _global_stats;
+  static GlobalTLABStats* global_stats() { return _global_stats; }
+
+public:
+  ThreadLocalAllocBuffer() : _allocation_fraction(TLABAllocationWeight), _allocated_before_last_gc(0) {
+    // do nothing.  tlabs must be inited by initialize() calls
+  }
+
+  static size_t min_size()                       { return align_object_size(MinTLABSize / HeapWordSize) + alignment_reserve(); }
+  static size_t max_size()                       { assert(_max_size != 0, "max_size not set up"); return _max_size; }
+  static size_t max_size_in_bytes()              { return max_size() * BytesPerWord; }
+  static void set_max_size(size_t max_size)      { _max_size = max_size; }
+
+  HeapWord* start() const                        { return _start; }
+  HeapWord* end() const                          { return _end; }
+  HeapWord* hard_end() const                     { return _end + alignment_reserve(); }
+  HeapWord* top() const                          { return _top; }
+  HeapWord* pf_top() const                       { return _pf_top; }
+  size_t desired_size() const                    { return _desired_size; }
+  size_t used() const                            { return pointer_delta(top(), start()); }
+  size_t used_bytes() const                      { return pointer_delta(top(), start(), 1); }
+  size_t free() const                            { return pointer_delta(end(), top()); }
+  // Don't discard tlab if remaining space is larger than this.
+  size_t refill_waste_limit() const              { return _refill_waste_limit; }
+
+  // Allocate size HeapWords. The memory is NOT initialized to zero.
+  inline HeapWord* allocate(size_t size);
+
+  // Reserve space at the end of TLAB
+  static size_t end_reserve() {
+    int reserve_size = typeArrayOopDesc::header_size(T_INT);
+    return MAX2(reserve_size, _reserve_for_allocation_prefetch);
+  }
+  static size_t alignment_reserve()              { return align_object_size(end_reserve()); }
+  static size_t alignment_reserve_in_bytes()     { return alignment_reserve() * HeapWordSize; }
+
+  // Return tlab size or remaining space in eden such that the
+  // space is large enough to hold obj_size and necessary fill space.
+  // Otherwise return 0;
+  inline size_t compute_size(size_t obj_size);
+
+  // Record slow allocation
+  inline void record_slow_allocation(size_t obj_size);
+
+  // Initialization at startup
+  static void startup_initialization();
+
+  // Make an in-use tlab parsable, optionally retiring and/or zapping it.
+  void make_parsable(bool retire, bool zap = true);
+
+  // Retire in-use tlab before allocation of a new tlab
+  void clear_before_allocation();
+
+  // Accumulate statistics across all tlabs before gc
+  static void accumulate_statistics_before_gc();
+
+  // Resize tlabs for all threads
+  static void resize_all_tlabs();
+
+  void fill(HeapWord* start, HeapWord* top, size_t new_size);
+  void initialize();
+
+  static size_t refill_waste_limit_increment()   { return TLABWasteIncrement; }
+
+  // Code generation support
+  static ByteSize start_offset()                 { return byte_offset_of(ThreadLocalAllocBuffer, _start); }
+  static ByteSize end_offset()                   { return byte_offset_of(ThreadLocalAllocBuffer, _end  ); }
+  static ByteSize top_offset()                   { return byte_offset_of(ThreadLocalAllocBuffer, _top  ); }
+  static ByteSize pf_top_offset()                { return byte_offset_of(ThreadLocalAllocBuffer, _pf_top  ); }
+  static ByteSize size_offset()                  { return byte_offset_of(ThreadLocalAllocBuffer, _desired_size ); }
+  static ByteSize refill_waste_limit_offset()    { return byte_offset_of(ThreadLocalAllocBuffer, _refill_waste_limit ); }
+
+  static ByteSize number_of_refills_offset()     { return byte_offset_of(ThreadLocalAllocBuffer, _number_of_refills ); }
+  static ByteSize fast_refill_waste_offset()     { return byte_offset_of(ThreadLocalAllocBuffer, _fast_refill_waste ); }
+  static ByteSize slow_allocations_offset()      { return byte_offset_of(ThreadLocalAllocBuffer, _slow_allocations ); }
+
+  void verify();
+};
+
+class GlobalTLABStats: public CHeapObj<mtThread> {
+private:
+
+  // Accumulate perfdata in private variables because
+  // PerfData should be write-only for security reasons
+  // (see perfData.hpp)
+  unsigned _allocating_threads;
+  unsigned _total_refills;
+  unsigned _max_refills;
+  size_t   _total_allocation;
+  size_t   _total_gc_waste;
+  size_t   _max_gc_waste;
+  size_t   _total_slow_refill_waste;
+  size_t   _max_slow_refill_waste;
+  size_t   _total_fast_refill_waste;
+  size_t   _max_fast_refill_waste;
+  unsigned _total_slow_allocations;
+  unsigned _max_slow_allocations;
+
+  PerfVariable* _perf_allocating_threads;
+  PerfVariable* _perf_total_refills;
+  PerfVariable* _perf_max_refills;
+  PerfVariable* _perf_allocation;
+  PerfVariable* _perf_gc_waste;
+  PerfVariable* _perf_max_gc_waste;
+  PerfVariable* _perf_slow_refill_waste;
+  PerfVariable* _perf_max_slow_refill_waste;
+  PerfVariable* _perf_fast_refill_waste;
+  PerfVariable* _perf_max_fast_refill_waste;
+  PerfVariable* _perf_slow_allocations;
+  PerfVariable* _perf_max_slow_allocations;
+
+  AdaptiveWeightedAverage _allocating_threads_avg;
+
+public:
+  GlobalTLABStats();
+
+  // Initialize all counters
+  void initialize();
+
+  // Write all perf counters to the perf_counters
+  void publish();
+
+  void print();
+
+  // Accessors
+  unsigned allocating_threads_avg() {
+    return MAX2((unsigned)(_allocating_threads_avg.average() + 0.5), 1U);
+  }
+
+  size_t allocation() {
+    return _total_allocation;
+  }
+
+  // Update methods
+
+  void update_allocating_threads() {
+    _allocating_threads++;
+  }
+  void update_number_of_refills(unsigned value) {
+    _total_refills += value;
+    _max_refills    = MAX2(_max_refills, value);
+  }
+  void update_allocation(size_t value) {
+    _total_allocation += value;
+  }
+  void update_gc_waste(size_t value) {
+    _total_gc_waste += value;
+    _max_gc_waste    = MAX2(_max_gc_waste, value);
+  }
+  void update_fast_refill_waste(size_t value) {
+    _total_fast_refill_waste += value;
+    _max_fast_refill_waste    = MAX2(_max_fast_refill_waste, value);
+  }
+  void update_slow_refill_waste(size_t value) {
+    _total_slow_refill_waste += value;
+    _max_slow_refill_waste    = MAX2(_max_slow_refill_waste, value);
+  }
+  void update_slow_allocations(unsigned value) {
+    _total_slow_allocations += value;
+    _max_slow_allocations    = MAX2(_max_slow_allocations, value);
+  }
+};
+
+#endif // SHARE_VM_GC_SHARED_THREADLOCALALLOCBUFFER_HPP