--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc/g1/heapRegionSet.hpp Wed May 13 15:16:06 2015 +0200
@@ -0,0 +1,295 @@
+/*
+ * Copyright (c) 2011, 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_G1_HEAPREGIONSET_HPP
+#define SHARE_VM_GC_G1_HEAPREGIONSET_HPP
+
+#include "gc/g1/heapRegion.hpp"
+
+// Large buffer for some cases where the output might be larger than normal.
+#define HRS_ERR_MSG_BUFSZ 512
+typedef FormatBuffer<HRS_ERR_MSG_BUFSZ> hrs_err_msg;
+
+// Set verification will be forced either if someone defines
+// HEAP_REGION_SET_FORCE_VERIFY to be 1, or in builds in which
+// asserts are compiled in.
+#ifndef HEAP_REGION_SET_FORCE_VERIFY
+#define HEAP_REGION_SET_FORCE_VERIFY defined(ASSERT)
+#endif // HEAP_REGION_SET_FORCE_VERIFY
+
+class hrs_ext_msg;
+
+class HRSMtSafeChecker : public CHeapObj<mtGC> {
+public:
+ virtual void check() = 0;
+};
+
+class MasterFreeRegionListMtSafeChecker : public HRSMtSafeChecker { public: void check(); };
+class SecondaryFreeRegionListMtSafeChecker : public HRSMtSafeChecker { public: void check(); };
+class HumongousRegionSetMtSafeChecker : public HRSMtSafeChecker { public: void check(); };
+class OldRegionSetMtSafeChecker : public HRSMtSafeChecker { public: void check(); };
+
+class HeapRegionSetCount VALUE_OBJ_CLASS_SPEC {
+ friend class VMStructs;
+ uint _length;
+ size_t _capacity;
+
+public:
+ HeapRegionSetCount() : _length(0), _capacity(0) { }
+
+ const uint length() const { return _length; }
+ const size_t capacity() const { return _capacity; }
+
+ void increment(uint length_to_add, size_t capacity_to_add) {
+ _length += length_to_add;
+ _capacity += capacity_to_add;
+ }
+
+ void decrement(const uint length_to_remove, const size_t capacity_to_remove) {
+ _length -= length_to_remove;
+ _capacity -= capacity_to_remove;
+ }
+};
+
+// Base class for all the classes that represent heap region sets. It
+// contains the basic attributes that each set needs to maintain
+// (e.g., length, region num, used bytes sum) plus any shared
+// functionality (e.g., verification).
+
+class HeapRegionSetBase VALUE_OBJ_CLASS_SPEC {
+ friend class VMStructs;
+private:
+ bool _is_humongous;
+ bool _is_free;
+ HRSMtSafeChecker* _mt_safety_checker;
+
+protected:
+ // The number of regions added to the set. If the set contains
+ // only humongous regions, this reflects only 'starts humongous'
+ // regions and does not include 'continues humongous' ones.
+ HeapRegionSetCount _count;
+
+ const char* _name;
+
+ bool _verify_in_progress;
+
+ // verify_region() is used to ensure that the contents of a region
+ // added to / removed from a set are consistent.
+ void verify_region(HeapRegion* hr) PRODUCT_RETURN;
+
+ // Indicates whether all regions in the set should be humongous or
+ // not. Only used during verification.
+ bool regions_humongous() { return _is_humongous; }
+
+ // Indicates whether all regions in the set should be free or
+ // not. Only used during verification.
+ bool regions_free() { return _is_free; }
+
+ void check_mt_safety() {
+ if (_mt_safety_checker != NULL) {
+ _mt_safety_checker->check();
+ }
+ }
+
+ virtual void fill_in_ext_msg_extra(hrs_ext_msg* msg) { }
+
+ HeapRegionSetBase(const char* name, bool humongous, bool free, HRSMtSafeChecker* mt_safety_checker);
+
+public:
+ const char* name() { return _name; }
+
+ uint length() const { return _count.length(); }
+
+ bool is_empty() { return _count.length() == 0; }
+
+ size_t total_capacity_bytes() {
+ return _count.capacity();
+ }
+
+ // It updates the fields of the set to reflect hr being added to
+ // the set and tags the region appropriately.
+ inline void add(HeapRegion* hr);
+
+ // It updates the fields of the set to reflect hr being removed
+ // from the set and tags the region appropriately.
+ inline void remove(HeapRegion* hr);
+
+ // fill_in_ext_msg() writes the the values of the set's attributes
+ // in the custom err_msg (hrs_ext_msg). fill_in_ext_msg_extra()
+ // allows subclasses to append further information.
+ void fill_in_ext_msg(hrs_ext_msg* msg, const char* message);
+
+ virtual void verify();
+ void verify_start();
+ void verify_next_region(HeapRegion* hr);
+ void verify_end();
+
+#if HEAP_REGION_SET_FORCE_VERIFY
+ void verify_optional() {
+ verify();
+ }
+#else // HEAP_REGION_SET_FORCE_VERIFY
+ void verify_optional() { }
+#endif // HEAP_REGION_SET_FORCE_VERIFY
+
+ virtual void print_on(outputStream* out, bool print_contents = false);
+};
+
+// Customized err_msg for heap region sets. Apart from a
+// assert/guarantee-specific message it also prints out the values of
+// the fields of the associated set. This can be very helpful in
+// diagnosing failures.
+class hrs_ext_msg : public hrs_err_msg {
+public:
+ hrs_ext_msg(HeapRegionSetBase* set, const char* message) : hrs_err_msg("%s", "") {
+ set->fill_in_ext_msg(this, message);
+ }
+};
+
+#define hrs_assert_sets_match(_set1_, _set2_) \
+ do { \
+ assert(((_set1_)->regions_humongous() == \
+ (_set2_)->regions_humongous()) && \
+ ((_set1_)->regions_free() == (_set2_)->regions_free()), \
+ hrs_err_msg("the contents of set %s and set %s should match", \
+ (_set1_)->name(), (_set2_)->name())); \
+ } while (0)
+
+// This class represents heap region sets whose members are not
+// explicitly tracked. It's helpful to group regions using such sets
+// so that we can reason about all the region groups in the heap using
+// the same interface (namely, the HeapRegionSetBase API).
+
+class HeapRegionSet : public HeapRegionSetBase {
+public:
+ HeapRegionSet(const char* name, bool humongous, HRSMtSafeChecker* mt_safety_checker):
+ HeapRegionSetBase(name, humongous, false /* free */, mt_safety_checker) { }
+
+ void bulk_remove(const HeapRegionSetCount& removed) {
+ _count.decrement(removed.length(), removed.capacity());
+ }
+};
+
+// A set that links all the regions added to it in a doubly-linked
+// sorted list. We should try to avoid doing operations that iterate over
+// such lists in performance critical paths. Typically we should
+// add / remove one region at a time or concatenate two lists.
+
+class FreeRegionListIterator;
+
+class FreeRegionList : public HeapRegionSetBase {
+ friend class FreeRegionListIterator;
+
+private:
+ HeapRegion* _head;
+ HeapRegion* _tail;
+
+ // _last is used to keep track of where we added an element the last
+ // time. It helps to improve performance when adding several ordered items in a row.
+ HeapRegion* _last;
+
+ static uint _unrealistically_long_length;
+
+ inline HeapRegion* remove_from_head_impl();
+ inline HeapRegion* remove_from_tail_impl();
+
+protected:
+ virtual void fill_in_ext_msg_extra(hrs_ext_msg* msg);
+
+ // See the comment for HeapRegionSetBase::clear()
+ virtual void clear();
+
+public:
+ FreeRegionList(const char* name, HRSMtSafeChecker* mt_safety_checker = NULL):
+ HeapRegionSetBase(name, false /* humongous */, true /* empty */, mt_safety_checker) {
+ clear();
+ }
+
+ void verify_list();
+
+#ifdef ASSERT
+ bool contains(HeapRegion* hr) const {
+ return hr->containing_set() == this;
+ }
+#endif
+
+ static void set_unrealistically_long_length(uint len);
+
+ // Add hr to the list. The region should not be a member of another set.
+ // Assumes that the list is ordered and will preserve that order. The order
+ // is determined by hrm_index.
+ inline void add_ordered(HeapRegion* hr);
+
+ // Removes from head or tail based on the given argument.
+ HeapRegion* remove_region(bool from_head);
+
+ // Merge two ordered lists. The result is also ordered. The order is
+ // determined by hrm_index.
+ void add_ordered(FreeRegionList* from_list);
+
+ // It empties the list by removing all regions from it.
+ void remove_all();
+
+ // Remove all (contiguous) regions from first to first + num_regions -1 from
+ // this list.
+ // Num_regions must be > 1.
+ void remove_starting_at(HeapRegion* first, uint num_regions);
+
+ virtual void verify();
+
+ virtual void print_on(outputStream* out, bool print_contents = false);
+};
+
+// Iterator class that provides a convenient way to iterate over the
+// regions of a FreeRegionList.
+
+class FreeRegionListIterator : public StackObj {
+private:
+ FreeRegionList* _list;
+ HeapRegion* _curr;
+
+public:
+ bool more_available() {
+ return _curr != NULL;
+ }
+
+ HeapRegion* get_next() {
+ assert(more_available(),
+ "get_next() should be called when more regions are available");
+
+ // If we are going to introduce a count in the iterator we should
+ // do the "cycle" check.
+
+ HeapRegion* hr = _curr;
+ _list->verify_region(hr);
+ _curr = hr->next();
+ return hr;
+ }
+
+ FreeRegionListIterator(FreeRegionList* list) : _curr(NULL), _list(list) {
+ _curr = list->_head;
+ }
+};
+
+#endif // SHARE_VM_GC_G1_HEAPREGIONSET_HPP