aoqi@0: /*
aoqi@0:  * Copyright (c) 2011, 2014, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  *
aoqi@0:  */
aoqi@0: 
aoqi@0: #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP
aoqi@0: #define SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP
aoqi@0: 
aoqi@0: #include "gc_implementation/g1/heapRegion.hpp"
aoqi@0: 
aoqi@0: // Large buffer for some cases where the output might be larger than normal.
aoqi@0: #define HRS_ERR_MSG_BUFSZ 512
aoqi@0: typedef FormatBuffer<HRS_ERR_MSG_BUFSZ> hrs_err_msg;
aoqi@0: 
aoqi@0: // Set verification will be forced either if someone defines
aoqi@0: // HEAP_REGION_SET_FORCE_VERIFY to be 1, or in builds in which
aoqi@0: // asserts are compiled in.
aoqi@0: #ifndef HEAP_REGION_SET_FORCE_VERIFY
aoqi@0: #define HEAP_REGION_SET_FORCE_VERIFY defined(ASSERT)
aoqi@0: #endif // HEAP_REGION_SET_FORCE_VERIFY
aoqi@0: 
aoqi@0: class hrs_ext_msg;
aoqi@0: 
aoqi@0: class HRSMtSafeChecker : public CHeapObj<mtGC> {
aoqi@0: public:
aoqi@0:   virtual void check() = 0;
aoqi@0: };
aoqi@0: 
aoqi@0: class MasterFreeRegionListMtSafeChecker    : public HRSMtSafeChecker { public: void check(); };
aoqi@0: class SecondaryFreeRegionListMtSafeChecker : public HRSMtSafeChecker { public: void check(); };
aoqi@0: class HumongousRegionSetMtSafeChecker      : public HRSMtSafeChecker { public: void check(); };
aoqi@0: class OldRegionSetMtSafeChecker            : public HRSMtSafeChecker { public: void check(); };
aoqi@0: 
aoqi@0: class HeapRegionSetCount VALUE_OBJ_CLASS_SPEC {
aoqi@0:   friend class VMStructs;
aoqi@0:   uint   _length;
aoqi@0:   size_t _capacity;
aoqi@0: 
aoqi@0: public:
aoqi@0:   HeapRegionSetCount() : _length(0), _capacity(0) { }
aoqi@0: 
aoqi@0:   const uint   length()   const { return _length;   }
aoqi@0:   const size_t capacity() const { return _capacity; }
aoqi@0: 
aoqi@0:   void increment(uint length_to_add, size_t capacity_to_add) {
aoqi@0:     _length += length_to_add;
aoqi@0:     _capacity += capacity_to_add;
aoqi@0:   }
aoqi@0: 
aoqi@0:   void decrement(const uint length_to_remove, const size_t capacity_to_remove) {
aoqi@0:     _length -= length_to_remove;
aoqi@0:     _capacity -= capacity_to_remove;
aoqi@0:   }
aoqi@0: };
aoqi@0: 
aoqi@0: // Base class for all the classes that represent heap region sets. It
aoqi@0: // contains the basic attributes that each set needs to maintain
aoqi@0: // (e.g., length, region num, used bytes sum) plus any shared
aoqi@0: // functionality (e.g., verification).
aoqi@0: 
aoqi@0: class HeapRegionSetBase VALUE_OBJ_CLASS_SPEC {
aoqi@0:   friend class VMStructs;
aoqi@0: private:
aoqi@0:   bool _is_humongous;
aoqi@0:   bool _is_empty;
aoqi@0:   HRSMtSafeChecker* _mt_safety_checker;
aoqi@0: 
aoqi@0: protected:
aoqi@0:   // The number of regions added to the set. If the set contains
aoqi@0:   // only humongous regions, this reflects only 'starts humongous'
aoqi@0:   // regions and does not include 'continues humongous' ones.
aoqi@0:   HeapRegionSetCount _count;
aoqi@0: 
aoqi@0:   const char* _name;
aoqi@0: 
aoqi@0:   bool _verify_in_progress;
aoqi@0: 
aoqi@0:   // verify_region() is used to ensure that the contents of a region
aoqi@0:   // added to / removed from a set are consistent.
aoqi@0:   void verify_region(HeapRegion* hr) PRODUCT_RETURN;
aoqi@0: 
aoqi@0:   // Indicates whether all regions in the set should be humongous or
aoqi@0:   // not. Only used during verification.
aoqi@0:   bool regions_humongous() { return _is_humongous; }
aoqi@0: 
aoqi@0:   // Indicates whether all regions in the set should be empty or
aoqi@0:   // not. Only used during verification.
aoqi@0:   bool regions_empty() { return _is_empty; }
aoqi@0: 
aoqi@0:   void check_mt_safety() {
aoqi@0:     if (_mt_safety_checker != NULL) {
aoqi@0:       _mt_safety_checker->check();
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   virtual void fill_in_ext_msg_extra(hrs_ext_msg* msg) { }
aoqi@0: 
aoqi@0:   HeapRegionSetBase(const char* name, bool humongous, bool empty, HRSMtSafeChecker* mt_safety_checker);
aoqi@0: 
aoqi@0: public:
aoqi@0:   const char* name() { return _name; }
aoqi@0: 
aoqi@0:   uint length() { return _count.length(); }
aoqi@0: 
aoqi@0:   bool is_empty() { return _count.length() == 0; }
aoqi@0: 
aoqi@0:   size_t total_capacity_bytes() {
aoqi@0:     return _count.capacity();
aoqi@0:   }
aoqi@0: 
aoqi@0:   // It updates the fields of the set to reflect hr being added to
aoqi@0:   // the set and tags the region appropriately.
aoqi@0:   inline void add(HeapRegion* hr);
aoqi@0: 
aoqi@0:   // It updates the fields of the set to reflect hr being removed
aoqi@0:   // from the set and tags the region appropriately.
aoqi@0:   inline void remove(HeapRegion* hr);
aoqi@0: 
aoqi@0:   // fill_in_ext_msg() writes the the values of the set's attributes
aoqi@0:   // in the custom err_msg (hrs_ext_msg). fill_in_ext_msg_extra()
aoqi@0:   // allows subclasses to append further information.
aoqi@0:   void fill_in_ext_msg(hrs_ext_msg* msg, const char* message);
aoqi@0: 
aoqi@0:   virtual void verify();
aoqi@0:   void verify_start();
aoqi@0:   void verify_next_region(HeapRegion* hr);
aoqi@0:   void verify_end();
aoqi@0: 
aoqi@0: #if HEAP_REGION_SET_FORCE_VERIFY
aoqi@0:   void verify_optional() {
aoqi@0:     verify();
aoqi@0:   }
aoqi@0: #else // HEAP_REGION_SET_FORCE_VERIFY
aoqi@0:   void verify_optional() { }
aoqi@0: #endif // HEAP_REGION_SET_FORCE_VERIFY
aoqi@0: 
aoqi@0:   virtual void print_on(outputStream* out, bool print_contents = false);
aoqi@0: };
aoqi@0: 
aoqi@0: // Customized err_msg for heap region sets. Apart from a
aoqi@0: // assert/guarantee-specific message it also prints out the values of
aoqi@0: // the fields of the associated set. This can be very helpful in
aoqi@0: // diagnosing failures.
aoqi@0: class hrs_ext_msg : public hrs_err_msg {
aoqi@0: public:
aoqi@0:   hrs_ext_msg(HeapRegionSetBase* set, const char* message) : hrs_err_msg("%s","") {
aoqi@0:     set->fill_in_ext_msg(this, message);
aoqi@0:   }
aoqi@0: };
aoqi@0: 
aoqi@0: #define hrs_assert_sets_match(_set1_, _set2_)                                 \
aoqi@0:   do {                                                                        \
aoqi@0:     assert(((_set1_)->regions_humongous() ==                                  \
aoqi@0:                                             (_set2_)->regions_humongous()) && \
aoqi@0:            ((_set1_)->regions_empty() == (_set2_)->regions_empty()),          \
aoqi@0:            hrs_err_msg("the contents of set %s and set %s should match",      \
aoqi@0:                        (_set1_)->name(), (_set2_)->name()));                  \
aoqi@0:   } while (0)
aoqi@0: 
aoqi@0: // This class represents heap region sets whose members are not
aoqi@0: // explicitly tracked. It's helpful to group regions using such sets
aoqi@0: // so that we can reason about all the region groups in the heap using
aoqi@0: // the same interface (namely, the HeapRegionSetBase API).
aoqi@0: 
aoqi@0: class HeapRegionSet : public HeapRegionSetBase {
aoqi@0: public:
aoqi@0:   HeapRegionSet(const char* name, bool humongous, HRSMtSafeChecker* mt_safety_checker):
aoqi@0:     HeapRegionSetBase(name, humongous, false /* empty */, mt_safety_checker) { }
aoqi@0: 
aoqi@0:   void bulk_remove(const HeapRegionSetCount& removed) {
aoqi@0:     _count.decrement(removed.length(), removed.capacity());
aoqi@0:   }
aoqi@0: };
aoqi@0: 
aoqi@0: // A set that links all the regions added to it in a doubly-linked
aoqi@0: // list. We should try to avoid doing operations that iterate over
aoqi@0: // such lists in performance critical paths. Typically we should
aoqi@0: // add / remove one region at a time or concatenate two lists. There are
aoqi@0: // two ways to treat your lists, ordered and un-ordered. All un-ordered
aoqi@0: // operations are done in constant time. To keep a list ordered only use
aoqi@0: // add_ordered() to add elements to the list. If a list is not ordered
aoqi@0: // from start, there is no way to sort it later.
aoqi@0: 
aoqi@0: class FreeRegionListIterator;
aoqi@0: 
aoqi@0: class FreeRegionList : public HeapRegionSetBase {
aoqi@0:   friend class FreeRegionListIterator;
aoqi@0: 
aoqi@0: private:
aoqi@0:   HeapRegion* _head;
aoqi@0:   HeapRegion* _tail;
aoqi@0: 
aoqi@0:   // _last is used to keep track of where we added an element the last
aoqi@0:   // time in ordered lists. It helps to improve performance when adding
aoqi@0:   // several ordered items in a row.
aoqi@0:   HeapRegion* _last;
aoqi@0: 
aoqi@0:   static uint _unrealistically_long_length;
aoqi@0: 
aoqi@0:   void add_as_head_or_tail(FreeRegionList* from_list, bool as_head);
aoqi@0: 
aoqi@0: protected:
aoqi@0:   virtual void fill_in_ext_msg_extra(hrs_ext_msg* msg);
aoqi@0: 
aoqi@0:   // See the comment for HeapRegionSetBase::clear()
aoqi@0:   virtual void clear();
aoqi@0: 
aoqi@0: public:
aoqi@0:   FreeRegionList(const char* name, HRSMtSafeChecker* mt_safety_checker = NULL):
aoqi@0:     HeapRegionSetBase(name, false /* humongous */, true /* empty */, mt_safety_checker) {
aoqi@0:     clear();
aoqi@0:   }
aoqi@0: 
aoqi@0:   void verify_list();
aoqi@0: 
aoqi@0:   HeapRegion* head() { return _head; }
aoqi@0:   HeapRegion* tail() { return _tail; }
aoqi@0: 
aoqi@0:   static void set_unrealistically_long_length(uint len);
aoqi@0: 
aoqi@0:   // Add hr to the list. The region should not be a member of another set.
aoqi@0:   // Assumes that the list is ordered and will preserve that order. The order
aoqi@0:   // is determined by hrs_index.
aoqi@0:   inline void add_ordered(HeapRegion* hr);
aoqi@0: 
aoqi@0:   // It adds hr to the list as the new head. The region should not be
aoqi@0:   // a member of another set.
aoqi@0:   inline void add_as_head(HeapRegion* hr);
aoqi@0: 
aoqi@0:   // It adds hr to the list as the new tail. The region should not be
aoqi@0:   // a member of another set.
aoqi@0:   inline void add_as_tail(HeapRegion* hr);
aoqi@0: 
aoqi@0:   // It removes and returns the head of the list. It assumes that the
aoqi@0:   // list is not empty so it will return a non-NULL value.
aoqi@0:   inline HeapRegion* remove_head();
aoqi@0: 
aoqi@0:   // Convenience method.
aoqi@0:   inline HeapRegion* remove_head_or_null();
aoqi@0: 
aoqi@0:   // Removes and returns the last element (_tail) of the list. It assumes
aoqi@0:   // that the list isn't empty so that it can return a non-NULL value.
aoqi@0:   inline HeapRegion* remove_tail();
aoqi@0: 
aoqi@0:   // Convenience method
aoqi@0:   inline HeapRegion* remove_tail_or_null();
aoqi@0: 
aoqi@0:   // Removes from head or tail based on the given argument.
aoqi@0:   inline HeapRegion* remove_region(bool from_head);
aoqi@0: 
aoqi@0:   // Merge two ordered lists. The result is also ordered. The order is
aoqi@0:   // determined by hrs_index.
aoqi@0:   void add_ordered(FreeRegionList* from_list);
aoqi@0: 
aoqi@0:   // It moves the regions from from_list to this list and empties
aoqi@0:   // from_list. The new regions will appear in the same order as they
aoqi@0:   // were in from_list and be linked in the beginning of this list.
aoqi@0:   void add_as_head(FreeRegionList* from_list);
aoqi@0: 
aoqi@0:   // It moves the regions from from_list to this list and empties
aoqi@0:   // from_list. The new regions will appear in the same order as they
aoqi@0:   // were in from_list and be linked in the end of this list.
aoqi@0:   void add_as_tail(FreeRegionList* from_list);
aoqi@0: 
aoqi@0:   // It empties the list by removing all regions from it.
aoqi@0:   void remove_all();
aoqi@0: 
aoqi@0:   // It removes all regions in the list that are pending for removal
aoqi@0:   // (i.e., they have been tagged with "pending_removal"). The list
aoqi@0:   // must not be empty, target_count should reflect the exact number
aoqi@0:   // of regions that are pending for removal in the list, and
aoqi@0:   // target_count should be > 1 (currently, we never need to remove a
aoqi@0:   // single region using this).
aoqi@0:   void remove_all_pending(uint target_count);
aoqi@0: 
aoqi@0:   virtual void verify();
aoqi@0: 
aoqi@0:   virtual void print_on(outputStream* out, bool print_contents = false);
aoqi@0: };
aoqi@0: 
aoqi@0: // Iterator class that provides a convenient way to iterate over the
aoqi@0: // regions of a HeapRegionLinkedList instance.
aoqi@0: 
aoqi@0: class FreeRegionListIterator : public StackObj {
aoqi@0: private:
aoqi@0:   FreeRegionList* _list;
aoqi@0:   HeapRegion*     _curr;
aoqi@0: 
aoqi@0: public:
aoqi@0:   bool more_available() {
aoqi@0:     return _curr != NULL;
aoqi@0:   }
aoqi@0: 
aoqi@0:   HeapRegion* get_next() {
aoqi@0:     assert(more_available(),
aoqi@0:            "get_next() should be called when more regions are available");
aoqi@0: 
aoqi@0:     // If we are going to introduce a count in the iterator we should
aoqi@0:     // do the "cycle" check.
aoqi@0: 
aoqi@0:     HeapRegion* hr = _curr;
aoqi@0:     _list->verify_region(hr);
aoqi@0:     _curr = hr->next();
aoqi@0:     return hr;
aoqi@0:   }
aoqi@0: 
aoqi@0:   FreeRegionListIterator(FreeRegionList* list) : _curr(NULL), _list(list) {
aoqi@0:     _curr = list->head();
aoqi@0:   }
aoqi@0: };
aoqi@0: 
aoqi@0: #endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP