hotspot/src/share/vm/gc_implementation/g1/collectionSetChooser.cpp
changeset 12382 6aaecb1cbfe1
parent 12381 1438e0fbfa27
child 15089 6becb5b6047a
--- a/hotspot/src/share/vm/gc_implementation/g1/collectionSetChooser.cpp	Wed Apr 18 07:21:15 2012 -0400
+++ b/hotspot/src/share/vm/gc_implementation/g1/collectionSetChooser.cpp	Wed Apr 18 13:39:55 2012 -0400
@@ -29,102 +29,6 @@
 #include "gc_implementation/g1/g1ErgoVerbose.hpp"
 #include "memory/space.inline.hpp"
 
-CSetChooserCache::CSetChooserCache() {
-  for (int i = 0; i < CacheLength; ++i)
-    _cache[i] = NULL;
-  clear();
-}
-
-void CSetChooserCache::clear() {
-  _occupancy = 0;
-  _first = 0;
-  for (int i = 0; i < CacheLength; ++i) {
-    HeapRegion *hr = _cache[i];
-    if (hr != NULL)
-      hr->set_sort_index(-1);
-    _cache[i] = NULL;
-  }
-}
-
-#ifndef PRODUCT
-bool CSetChooserCache::verify() {
-  guarantee(false, "CSetChooserCache::verify(): don't call this any more");
-
-  int index = _first;
-  HeapRegion *prev = NULL;
-  for (int i = 0; i < _occupancy; ++i) {
-    guarantee(_cache[index] != NULL, "cache entry should not be empty");
-    HeapRegion *hr = _cache[index];
-    guarantee(!hr->is_young(), "should not be young!");
-    if (prev != NULL) {
-      guarantee(prev->gc_efficiency() >= hr->gc_efficiency(),
-                "cache should be correctly ordered");
-    }
-    guarantee(hr->sort_index() == get_sort_index(index),
-              "sort index should be correct");
-    index = trim_index(index + 1);
-    prev = hr;
-  }
-
-  for (int i = 0; i < (CacheLength - _occupancy); ++i) {
-    guarantee(_cache[index] == NULL, "cache entry should be empty");
-    index = trim_index(index + 1);
-  }
-
-  guarantee(index == _first, "we should have reached where we started from");
-  return true;
-}
-#endif // PRODUCT
-
-void CSetChooserCache::insert(HeapRegion *hr) {
-  guarantee(false, "CSetChooserCache::insert(): don't call this any more");
-
-  assert(!is_full(), "cache should not be empty");
-  hr->calc_gc_efficiency();
-
-  int empty_index;
-  if (_occupancy == 0) {
-    empty_index = _first;
-  } else {
-    empty_index = trim_index(_first + _occupancy);
-    assert(_cache[empty_index] == NULL, "last slot should be empty");
-    int last_index = trim_index(empty_index - 1);
-    HeapRegion *last = _cache[last_index];
-    assert(last != NULL,"as the cache is not empty, last should not be empty");
-    while (empty_index != _first &&
-           last->gc_efficiency() < hr->gc_efficiency()) {
-      _cache[empty_index] = last;
-      last->set_sort_index(get_sort_index(empty_index));
-      empty_index = last_index;
-      last_index = trim_index(last_index - 1);
-      last = _cache[last_index];
-    }
-  }
-  _cache[empty_index] = hr;
-  hr->set_sort_index(get_sort_index(empty_index));
-
-  ++_occupancy;
-  assert(verify(), "cache should be consistent");
-}
-
-HeapRegion *CSetChooserCache::remove_first() {
-  guarantee(false, "CSetChooserCache::remove_first(): "
-                   "don't call this any more");
-
-  if (_occupancy > 0) {
-    assert(_cache[_first] != NULL, "cache should have at least one region");
-    HeapRegion *ret = _cache[_first];
-    _cache[_first] = NULL;
-    ret->set_sort_index(-1);
-    --_occupancy;
-    _first = trim_index(_first + 1);
-    assert(verify(), "cache should be consistent");
-    return ret;
-  } else {
-    return NULL;
-  }
-}
-
 // Even though we don't use the GC efficiency in our heuristics as
 // much as we used to, we still order according to GC efficiency. This
 // will cause regions with a lot of live objects and large RSets to
@@ -134,7 +38,7 @@
 // the ones we'll skip are ones with both large RSets and a lot of
 // live objects, not the ones with just a lot of live objects if we
 // ordered according to the amount of reclaimable bytes per region.
-static int orderRegions(HeapRegion* hr1, HeapRegion* hr2) {
+static int order_regions(HeapRegion* hr1, HeapRegion* hr2) {
   if (hr1 == NULL) {
     if (hr2 == NULL) {
       return 0;
@@ -156,8 +60,8 @@
   }
 }
 
-static int orderRegions(HeapRegion** hr1p, HeapRegion** hr2p) {
-  return orderRegions(*hr1p, *hr2p);
+static int order_regions(HeapRegion** hr1p, HeapRegion** hr2p) {
+  return order_regions(*hr1p, *hr2p);
 }
 
 CollectionSetChooser::CollectionSetChooser() :
@@ -175,105 +79,74 @@
   //
   // Note: containing object is allocated on C heap since it is CHeapObj.
   //
-  _markedRegions((ResourceObj::set_allocation_type((address)&_markedRegions,
+  _regions((ResourceObj::set_allocation_type((address) &_regions,
                                              ResourceObj::C_HEAP),
                   100), true /* C_Heap */),
-    _curr_index(0), _length(0),
-    _regionLiveThresholdBytes(0), _remainingReclaimableBytes(0),
-    _first_par_unreserved_idx(0) {
-  _regionLiveThresholdBytes =
+    _curr_index(0), _length(0), _first_par_unreserved_idx(0),
+    _region_live_threshold_bytes(0), _remaining_reclaimable_bytes(0) {
+  _region_live_threshold_bytes =
     HeapRegion::GrainBytes * (size_t) G1OldCSetRegionLiveThresholdPercent / 100;
 }
 
 #ifndef PRODUCT
-bool CollectionSetChooser::verify() {
-  guarantee(_length >= 0, err_msg("_length: %d", _length));
-  guarantee(0 <= _curr_index && _curr_index <= _length,
-            err_msg("_curr_index: %d _length: %d", _curr_index, _length));
-  int index = 0;
+void CollectionSetChooser::verify() {
+  guarantee(_length <= regions_length(),
+         err_msg("_length: %u regions length: %u", _length, regions_length()));
+  guarantee(_curr_index <= _length,
+            err_msg("_curr_index: %u _length: %u", _curr_index, _length));
+  uint index = 0;
   size_t sum_of_reclaimable_bytes = 0;
   while (index < _curr_index) {
-    guarantee(_markedRegions.at(index) == NULL,
+    guarantee(regions_at(index) == NULL,
               "all entries before _curr_index should be NULL");
     index += 1;
   }
   HeapRegion *prev = NULL;
   while (index < _length) {
-    HeapRegion *curr = _markedRegions.at(index++);
-    guarantee(curr != NULL, "Regions in _markedRegions array cannot be NULL");
-    int si = curr->sort_index();
+    HeapRegion *curr = regions_at(index++);
+    guarantee(curr != NULL, "Regions in _regions array cannot be NULL");
     guarantee(!curr->is_young(), "should not be young!");
     guarantee(!curr->isHumongous(), "should not be humongous!");
-    guarantee(si > -1 && si == (index-1), "sort index invariant");
     if (prev != NULL) {
-      guarantee(orderRegions(prev, curr) != 1,
+      guarantee(order_regions(prev, curr) != 1,
                 err_msg("GC eff prev: %1.4f GC eff curr: %1.4f",
                         prev->gc_efficiency(), curr->gc_efficiency()));
     }
     sum_of_reclaimable_bytes += curr->reclaimable_bytes();
     prev = curr;
   }
-  guarantee(sum_of_reclaimable_bytes == _remainingReclaimableBytes,
+  guarantee(sum_of_reclaimable_bytes == _remaining_reclaimable_bytes,
             err_msg("reclaimable bytes inconsistent, "
                     "remaining: "SIZE_FORMAT" sum: "SIZE_FORMAT,
-                    _remainingReclaimableBytes, sum_of_reclaimable_bytes));
-  return true;
+                    _remaining_reclaimable_bytes, sum_of_reclaimable_bytes));
 }
-#endif
-
-void CollectionSetChooser::fillCache() {
-  guarantee(false, "fillCache: don't call this any more");
+#endif // !PRODUCT
 
-  while (!_cache.is_full() && (_curr_index < _length)) {
-    HeapRegion* hr = _markedRegions.at(_curr_index);
-    assert(hr != NULL,
-           err_msg("Unexpected NULL hr in _markedRegions at index %d",
-                   _curr_index));
-    _curr_index += 1;
-    assert(!hr->is_young(), "should not be young!");
-    assert(hr->sort_index() == _curr_index-1, "sort_index invariant");
-    _markedRegions.at_put(hr->sort_index(), NULL);
-    _cache.insert(hr);
-    assert(!_cache.is_empty(), "cache should not be empty");
-  }
-  assert(verify(), "cache should be consistent");
-}
-
-void CollectionSetChooser::sortMarkedHeapRegions() {
+void CollectionSetChooser::sort_regions() {
   // First trim any unused portion of the top in the parallel case.
   if (_first_par_unreserved_idx > 0) {
-    if (G1PrintParCleanupStats) {
-      gclog_or_tty->print("     Truncating _markedRegions from %d to %d.\n",
-                          _markedRegions.length(), _first_par_unreserved_idx);
-    }
-    assert(_first_par_unreserved_idx <= _markedRegions.length(),
+    assert(_first_par_unreserved_idx <= regions_length(),
            "Or we didn't reserved enough length");
-    _markedRegions.trunc_to(_first_par_unreserved_idx);
+    regions_trunc_to(_first_par_unreserved_idx);
   }
-  _markedRegions.sort(orderRegions);
-  assert(_length <= _markedRegions.length(), "Requirement");
-  assert(_length == 0 || _markedRegions.at(_length - 1) != NULL,
-         "Testing _length");
-  assert(_length == _markedRegions.length() ||
-                        _markedRegions.at(_length) == NULL, "Testing _length");
-  if (G1PrintParCleanupStats) {
-    gclog_or_tty->print_cr("     Sorted %d marked regions.", _length);
+  _regions.sort(order_regions);
+  assert(_length <= regions_length(), "Requirement");
+#ifdef ASSERT
+  for (uint i = 0; i < _length; i++) {
+    assert(regions_at(i) != NULL, "Should be true by sorting!");
   }
-  for (int i = 0; i < _length; i++) {
-    assert(_markedRegions.at(i) != NULL, "Should be true by sorting!");
-    _markedRegions.at(i)->set_sort_index(i);
-  }
+#endif // ASSERT
   if (G1PrintRegionLivenessInfo) {
     G1PrintRegionLivenessInfoClosure cl(gclog_or_tty, "Post-Sorting");
-    for (int i = 0; i < _length; ++i) {
-      HeapRegion* r = _markedRegions.at(i);
+    for (uint i = 0; i < _length; ++i) {
+      HeapRegion* r = regions_at(i);
       cl.doHeapRegion(r);
     }
   }
-  assert(verify(), "CSet chooser verification");
+  verify();
 }
 
-uint CollectionSetChooser::calcMinOldCSetLength() {
+uint CollectionSetChooser::calc_min_old_cset_length() {
   // The min old CSet region bound is based on the maximum desired
   // number of mixed GCs after a cycle. I.e., even if some old regions
   // look expensive, we should add them to the CSet anyway to make
@@ -294,7 +167,7 @@
   return (uint) result;
 }
 
-uint CollectionSetChooser::calcMaxOldCSetLength() {
+uint CollectionSetChooser::calc_max_old_cset_length() {
   // The max old CSet region bound is based on the threshold expressed
   // as a percentage of the heap size. I.e., it should bound the
   // number of old regions added to the CSet irrespective of how many
@@ -311,18 +184,18 @@
   return (uint) result;
 }
 
-void CollectionSetChooser::addMarkedHeapRegion(HeapRegion* hr) {
+void CollectionSetChooser::add_region(HeapRegion* hr) {
   assert(!hr->isHumongous(),
          "Humongous regions shouldn't be added to the collection set");
   assert(!hr->is_young(), "should not be young!");
-  _markedRegions.append(hr);
+  _regions.append(hr);
   _length++;
-  _remainingReclaimableBytes += hr->reclaimable_bytes();
+  _remaining_reclaimable_bytes += hr->reclaimable_bytes();
   hr->calc_gc_efficiency();
 }
 
-void CollectionSetChooser::prepareForAddMarkedHeapRegionsPar(uint n_regions,
-                                                             uint chunkSize) {
+void CollectionSetChooser::prepare_for_par_region_addition(uint n_regions,
+                                                           uint chunk_size) {
   _first_par_unreserved_idx = 0;
   uint n_threads = (uint) ParallelGCThreads;
   if (UseDynamicNumberOfGCThreads) {
@@ -335,56 +208,46 @@
     n_threads = MAX2(G1CollectedHeap::heap()->workers()->active_workers(),
                      1U);
   }
-  uint max_waste = n_threads * chunkSize;
-  // it should be aligned with respect to chunkSize
-  uint aligned_n_regions = (n_regions + chunkSize - 1) / chunkSize * chunkSize;
-  assert(aligned_n_regions % chunkSize == 0, "should be aligned");
-  _markedRegions.at_put_grow((int) (aligned_n_regions + max_waste - 1), NULL);
+  uint max_waste = n_threads * chunk_size;
+  // it should be aligned with respect to chunk_size
+  uint aligned_n_regions = (n_regions + chunk_size - 1) / chunk_size * chunk_size;
+  assert(aligned_n_regions % chunk_size == 0, "should be aligned");
+  regions_at_put_grow(aligned_n_regions + max_waste - 1, NULL);
 }
 
-jint CollectionSetChooser::getParMarkedHeapRegionChunk(jint n_regions) {
-  // Don't do this assert because this can be called at a point
-  // where the loop up stream will not execute again but might
-  // try to claim more chunks (loop test has not been done yet).
-  // assert(_markedRegions.length() > _first_par_unreserved_idx,
-  //  "Striding beyond the marked regions");
-  jint res = Atomic::add(n_regions, &_first_par_unreserved_idx);
-  assert(_markedRegions.length() > res + n_regions - 1,
+uint CollectionSetChooser::claim_array_chunk(uint chunk_size) {
+  uint res = (uint) Atomic::add((jint) chunk_size,
+                                (volatile jint*) &_first_par_unreserved_idx);
+  assert(regions_length() > res + chunk_size - 1,
          "Should already have been expanded");
-  return res - n_regions;
+  return res - chunk_size;
 }
 
-void CollectionSetChooser::setMarkedHeapRegion(jint index, HeapRegion* hr) {
-  assert(_markedRegions.at(index) == NULL, "precondition");
+void CollectionSetChooser::set_region(uint index, HeapRegion* hr) {
+  assert(regions_at(index) == NULL, "precondition");
   assert(!hr->is_young(), "should not be young!");
-  _markedRegions.at_put(index, hr);
+  regions_at_put(index, hr);
   hr->calc_gc_efficiency();
 }
 
-void CollectionSetChooser::updateTotals(jint region_num,
-                                        size_t reclaimable_bytes) {
+void CollectionSetChooser::update_totals(uint region_num,
+                                         size_t reclaimable_bytes) {
   // Only take the lock if we actually need to update the totals.
   if (region_num > 0) {
     assert(reclaimable_bytes > 0, "invariant");
     // We could have just used atomics instead of taking the
     // lock. However, we currently don't have an atomic add for size_t.
     MutexLockerEx x(ParGCRareEvent_lock, Mutex::_no_safepoint_check_flag);
-    _length += (int) region_num;
-    _remainingReclaimableBytes += reclaimable_bytes;
+    _length += region_num;
+    _remaining_reclaimable_bytes += reclaimable_bytes;
   } else {
     assert(reclaimable_bytes == 0, "invariant");
   }
 }
 
-void CollectionSetChooser::clearMarkedHeapRegions() {
-  for (int i = 0; i < _markedRegions.length(); i++) {
-    HeapRegion* r = _markedRegions.at(i);
-    if (r != NULL) {
-      r->set_sort_index(-1);
-    }
-  }
-  _markedRegions.clear();
+void CollectionSetChooser::clear() {
+  _regions.clear();
   _curr_index = 0;
   _length = 0;
-  _remainingReclaimableBytes = 0;
+  _remaining_reclaimable_bytes = 0;
 };