--- /dev/null	2018-11-30 10:10:44.238550338 +0100
+++ new/src/hotspot/share/gc/shenandoah/shenandoahHeapRegionCounters.cpp	2018-11-30 21:09:11.036796008 +0100
@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) 2016, 2018, Red Hat, Inc. All rights reserved.
+ *
+ * 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.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "gc/shenandoah/shenandoahHeap.inline.hpp"
+#include "gc/shenandoah/shenandoahHeapRegion.hpp"
+#include "gc/shenandoah/shenandoahHeapRegionSet.hpp"
+#include "gc/shenandoah/shenandoahHeapRegionCounters.hpp"
+#include "memory/resourceArea.hpp"
+#include "runtime/perfData.inline.hpp"
+
+ShenandoahHeapRegionCounters::ShenandoahHeapRegionCounters() :
+  _last_sample_millis(0)
+{
+  if (UsePerfData && ShenandoahRegionSampling) {
+    EXCEPTION_MARK;
+    ResourceMark rm;
+    ShenandoahHeap* heap = ShenandoahHeap::heap();
+    size_t num_regions = heap->num_regions();
+    const char* cns = PerfDataManager::name_space("shenandoah", "regions");
+    _name_space = NEW_C_HEAP_ARRAY(char, strlen(cns)+1, mtGC);
+    strcpy(_name_space, cns);
+
+    const char* cname = PerfDataManager::counter_name(_name_space, "timestamp");
+    _timestamp = PerfDataManager::create_long_variable(SUN_GC, cname, PerfData::U_None, CHECK);
+
+    cname = PerfDataManager::counter_name(_name_space, "max_regions");
+    PerfDataManager::create_constant(SUN_GC, cname, PerfData::U_None, num_regions, CHECK);
+
+    cname = PerfDataManager::counter_name(_name_space, "region_size");
+    PerfDataManager::create_constant(SUN_GC, cname, PerfData::U_None, ShenandoahHeapRegion::region_size_bytes() >> 10, CHECK);
+
+    cname = PerfDataManager::counter_name(_name_space, "status");
+    _status = PerfDataManager::create_long_variable(SUN_GC, cname,
+                                                    PerfData::U_None, CHECK);
+
+    _regions_data = NEW_C_HEAP_ARRAY(PerfVariable*, num_regions, mtGC);
+    for (uint i = 0; i < num_regions; i++) {
+      const char* reg_name = PerfDataManager::name_space(_name_space, "region", i);
+      const char* data_name = PerfDataManager::counter_name(reg_name, "data");
+      const char* ns = PerfDataManager::ns_to_string(SUN_GC);
+      const char* fullname = PerfDataManager::counter_name(ns, data_name);
+      assert(!PerfDataManager::exists(fullname), "must not exist");
+      _regions_data[i] = PerfDataManager::create_long_variable(SUN_GC, data_name,
+                                                               PerfData::U_None, CHECK);
+    }
+  }
+}
+
+ShenandoahHeapRegionCounters::~ShenandoahHeapRegionCounters() {
+  if (_name_space != NULL) FREE_C_HEAP_ARRAY(char, _name_space);
+}
+
+void ShenandoahHeapRegionCounters::update() {
+  if (ShenandoahRegionSampling) {
+    jlong current = os::javaTimeMillis();
+    jlong last = _last_sample_millis;
+    if (current - last > ShenandoahRegionSamplingRate &&
+            Atomic::cmpxchg(current, &_last_sample_millis, last) == last) {
+
+      ShenandoahHeap* heap = ShenandoahHeap::heap();
+      jlong status = 0;
+      if (heap->is_concurrent_mark_in_progress())      status |= 1 << 0;
+      if (heap->is_evacuation_in_progress())           status |= 1 << 1;
+      if (heap->is_update_refs_in_progress())          status |= 1 << 2;
+      if (heap->is_concurrent_traversal_in_progress()) status |= 1 << 3;
+      _status->set_value(status);
+
+      _timestamp->set_value(os::elapsed_counter());
+
+      size_t num_regions = heap->num_regions();
+
+      {
+        ShenandoahHeapLocker locker(heap->lock());
+        size_t rs = ShenandoahHeapRegion::region_size_bytes();
+        for (uint i = 0; i < num_regions; i++) {
+          ShenandoahHeapRegion* r = heap->get_region(i);
+          jlong data = 0;
+          data |= ((100 * r->used() / rs)                & PERCENT_MASK) << USED_SHIFT;
+          data |= ((100 * r->get_live_data_bytes() / rs) & PERCENT_MASK) << LIVE_SHIFT;
+          data |= ((100 * r->get_tlab_allocs() / rs)     & PERCENT_MASK) << TLAB_SHIFT;
+          data |= ((100 * r->get_gclab_allocs() / rs)    & PERCENT_MASK) << GCLAB_SHIFT;
+          data |= ((100 * r->get_shared_allocs() / rs)   & PERCENT_MASK) << SHARED_SHIFT;
+          data |= (r->state_ordinal() & STATUS_MASK) << STATUS_SHIFT;
+          _regions_data[i]->set_value(data);
+        }
+      }
+
+    }
+  }
+}