tonyp@2472: /*
tonyp@3457:  * Copyright (c) 2011, 2012, Oracle and/or its affiliates. All rights reserved.
tonyp@2472:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
tonyp@2472:  *
tonyp@2472:  * This code is free software; you can redistribute it and/or modify it
tonyp@2472:  * under the terms of the GNU General Public License version 2 only, as
tonyp@2472:  * published by the Free Software Foundation.
tonyp@2472:  *
tonyp@2472:  * This code is distributed in the hope that it will be useful, but WITHOUT
tonyp@2472:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
tonyp@2472:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
tonyp@2472:  * version 2 for more details (a copy is included in the LICENSE file that
tonyp@2472:  * accompanied this code).
tonyp@2472:  *
tonyp@2472:  * You should have received a copy of the GNU General Public License version
tonyp@2472:  * 2 along with this work; if not, write to the Free Software Foundation,
tonyp@2472:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
tonyp@2472:  *
tonyp@2472:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
tonyp@2472:  * or visit www.oracle.com if you need additional information or have any
tonyp@2472:  * questions.
tonyp@2472:  *
tonyp@2472:  */
tonyp@2472: 
tonyp@2472: #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP
tonyp@2472: #define SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP
tonyp@2472: 
tonyp@2472: #include "gc_implementation/g1/heapRegion.hpp"
tonyp@2472: 
tonyp@2472: // Large buffer for some cases where the output might be larger than normal.
tonyp@2643: #define HRS_ERR_MSG_BUFSZ 512
tonyp@2643: typedef FormatBuffer<HRS_ERR_MSG_BUFSZ> hrs_err_msg;
tonyp@2472: 
tonyp@2472: // Set verification will be forced either if someone defines
tonyp@2472: // HEAP_REGION_SET_FORCE_VERIFY to be 1, or in builds in which
tonyp@2472: // asserts are compiled in.
tonyp@2472: #ifndef HEAP_REGION_SET_FORCE_VERIFY
tonyp@2472: #define HEAP_REGION_SET_FORCE_VERIFY defined(ASSERT)
tonyp@2472: #endif // HEAP_REGION_SET_FORCE_VERIFY
tonyp@2472: 
brutisso@6385: class hrs_ext_msg;
brutisso@6385: 
brutisso@6385: class HRSMtSafeChecker : public CHeapObj<mtGC> {
brutisso@6385: public:
brutisso@6385:   virtual void check() = 0;
brutisso@6385: };
brutisso@6385: 
brutisso@6385: class MasterFreeRegionListMtSafeChecker    : public HRSMtSafeChecker { public: void check(); };
brutisso@6385: class SecondaryFreeRegionListMtSafeChecker : public HRSMtSafeChecker { public: void check(); };
brutisso@6385: class HumongousRegionSetMtSafeChecker      : public HRSMtSafeChecker { public: void check(); };
brutisso@6385: class OldRegionSetMtSafeChecker            : public HRSMtSafeChecker { public: void check(); };
brutisso@6385: 
brutisso@6385: class HeapRegionSetCount VALUE_OBJ_CLASS_SPEC {
brutisso@6385:   friend class VMStructs;
brutisso@6385:   uint   _length;
brutisso@6385:   size_t _capacity;
brutisso@6385: 
brutisso@6385: public:
brutisso@6385:   HeapRegionSetCount() : _length(0), _capacity(0) { }
brutisso@6385: 
brutisso@6385:   const uint   length()   const { return _length;   }
brutisso@6385:   const size_t capacity() const { return _capacity; }
brutisso@6385: 
brutisso@6385:   void increment(uint length_to_add, size_t capacity_to_add) {
brutisso@6385:     _length += length_to_add;
brutisso@6385:     _capacity += capacity_to_add;
brutisso@6385:   }
brutisso@6385: 
brutisso@6385:   void decrement(const uint length_to_remove, const size_t capacity_to_remove) {
brutisso@6385:     _length -= length_to_remove;
brutisso@6385:     _capacity -= capacity_to_remove;
brutisso@6385:   }
brutisso@6385: };
tonyp@2472: 
tonyp@2472: // Base class for all the classes that represent heap region sets. It
tonyp@2472: // contains the basic attributes that each set needs to maintain
tonyp@2472: // (e.g., length, region num, used bytes sum) plus any shared
tonyp@2472: // functionality (e.g., verification).
tonyp@2472: 
tonyp@2472: class HeapRegionSetBase VALUE_OBJ_CLASS_SPEC {
tonyp@3457:   friend class VMStructs;
brutisso@6385: private:
brutisso@6385:   bool _is_humongous;
brutisso@6385:   bool _is_empty;
brutisso@6385:   HRSMtSafeChecker* _mt_safety_checker;
tonyp@2472: 
tonyp@2472: protected:
tonyp@2472:   // The number of regions added to the set. If the set contains
tonyp@2472:   // only humongous regions, this reflects only 'starts humongous'
tonyp@2472:   // regions and does not include 'continues humongous' ones.
brutisso@6385:   HeapRegionSetCount _count;
tonyp@2472: 
tonyp@2472:   const char* _name;
tonyp@2472: 
brutisso@6385:   bool _verify_in_progress;
tonyp@3268: 
tonyp@2472:   // verify_region() is used to ensure that the contents of a region
brutisso@6385:   // added to / removed from a set are consistent.
brutisso@6385:   void verify_region(HeapRegion* hr) PRODUCT_RETURN;
tonyp@2472: 
tonyp@2472:   // Indicates whether all regions in the set should be humongous or
tonyp@2472:   // not. Only used during verification.
brutisso@6385:   bool regions_humongous() { return _is_humongous; }
tonyp@2472: 
tonyp@2472:   // Indicates whether all regions in the set should be empty or
tonyp@2472:   // not. Only used during verification.
brutisso@6385:   bool regions_empty() { return _is_empty; }
tonyp@2472: 
brutisso@6385:   void check_mt_safety() {
brutisso@6385:     if (_mt_safety_checker != NULL) {
brutisso@6385:       _mt_safety_checker->check();
brutisso@6385:     }
brutisso@6385:   }
brutisso@6385: 
brutisso@6385:   virtual void fill_in_ext_msg_extra(hrs_ext_msg* msg) { }
brutisso@6385: 
brutisso@6385:   HeapRegionSetBase(const char* name, bool humongous, bool empty, HRSMtSafeChecker* mt_safety_checker);
brutisso@6385: 
brutisso@6385: public:
brutisso@6385:   const char* name() { return _name; }
brutisso@6385: 
brutisso@6385:   uint length() { return _count.length(); }
brutisso@6385: 
brutisso@6385:   bool is_empty() { return _count.length() == 0; }
brutisso@6385: 
brutisso@6385:   size_t total_capacity_bytes() {
brutisso@6385:     return _count.capacity();
brutisso@6385:   }
brutisso@6385: 
brutisso@6385:   // It updates the fields of the set to reflect hr being added to
brutisso@6385:   // the set and tags the region appropriately.
brutisso@6385:   inline void add(HeapRegion* hr);
brutisso@6385: 
brutisso@6385:   // It updates the fields of the set to reflect hr being removed
brutisso@6385:   // from the set and tags the region appropriately.
brutisso@6385:   inline void remove(HeapRegion* hr);
tonyp@2472: 
tonyp@2472:   // fill_in_ext_msg() writes the the values of the set's attributes
tonyp@2643:   // in the custom err_msg (hrs_ext_msg). fill_in_ext_msg_extra()
tonyp@2472:   // allows subclasses to append further information.
tonyp@2643:   void fill_in_ext_msg(hrs_ext_msg* msg, const char* message);
tonyp@2472: 
tonyp@2472:   virtual void verify();
tonyp@2472:   void verify_start();
tonyp@2472:   void verify_next_region(HeapRegion* hr);
tonyp@2472:   void verify_end();
tonyp@2472: 
tonyp@2472: #if HEAP_REGION_SET_FORCE_VERIFY
tonyp@2472:   void verify_optional() {
tonyp@2472:     verify();
tonyp@2472:   }
tonyp@2472: #else // HEAP_REGION_SET_FORCE_VERIFY
tonyp@2472:   void verify_optional() { }
tonyp@2472: #endif // HEAP_REGION_SET_FORCE_VERIFY
tonyp@2472: 
tonyp@2472:   virtual void print_on(outputStream* out, bool print_contents = false);
tonyp@2472: };
tonyp@2472: 
tonyp@2472: // Customized err_msg for heap region sets. Apart from a
tonyp@2472: // assert/guarantee-specific message it also prints out the values of
tonyp@2472: // the fields of the associated set. This can be very helpful in
tonyp@2472: // diagnosing failures.
tonyp@2643: class hrs_ext_msg : public hrs_err_msg {
tonyp@2472: public:
tonyp@2643:   hrs_ext_msg(HeapRegionSetBase* set, const char* message) : hrs_err_msg("") {
tonyp@2472:     set->fill_in_ext_msg(this, message);
tonyp@2472:   }
tonyp@2472: };
tonyp@2472: 
tonyp@2643: #define hrs_assert_sets_match(_set1_, _set2_)                                 \
tonyp@2472:   do {                                                                        \
tonyp@2472:     assert(((_set1_)->regions_humongous() ==                                  \
tonyp@2472:                                             (_set2_)->regions_humongous()) && \
tonyp@2472:            ((_set1_)->regions_empty() == (_set2_)->regions_empty()),          \
tonyp@2643:            hrs_err_msg("the contents of set %s and set %s should match",      \
tonyp@2472:                        (_set1_)->name(), (_set2_)->name()));                  \
tonyp@2472:   } while (0)
tonyp@2472: 
tonyp@2472: // This class represents heap region sets whose members are not
tonyp@2472: // explicitly tracked. It's helpful to group regions using such sets
tonyp@2472: // so that we can reason about all the region groups in the heap using
tonyp@2472: // the same interface (namely, the HeapRegionSetBase API).
tonyp@2472: 
tonyp@2472: class HeapRegionSet : public HeapRegionSetBase {
brutisso@6385: public:
brutisso@6385:   HeapRegionSet(const char* name, bool humongous, HRSMtSafeChecker* mt_safety_checker):
brutisso@6385:     HeapRegionSetBase(name, humongous, false /* empty */, mt_safety_checker) { }
tonyp@2472: 
brutisso@6385:   void bulk_remove(const HeapRegionSetCount& removed) {
brutisso@6385:     _count.decrement(removed.length(), removed.capacity());
tonyp@2472:   }
tonyp@2472: };
tonyp@2472: 
tonyp@2472: // A set that links all the regions added to it in a singly-linked
tonyp@2472: // list. We should try to avoid doing operations that iterate over
tonyp@2472: // such lists in performance critical paths. Typically we should
tonyp@2472: // add / remove one region at a time or concatenate two lists. All
tonyp@2472: // those operations are done in constant time.
tonyp@2472: 
brutisso@6385: class FreeRegionListIterator;
tonyp@2472: 
brutisso@6385: class FreeRegionList : public HeapRegionSetBase {
brutisso@6385:   friend class FreeRegionListIterator;
tonyp@2472: 
tonyp@2472: private:
tonyp@2472:   HeapRegion* _head;
tonyp@2472:   HeapRegion* _tail;
tonyp@2472: 
brutisso@6385:   static uint _unrealistically_long_length;
brutisso@6385: 
brutisso@6385:   void add_as_head_or_tail(FreeRegionList* from_list, bool as_head);
tonyp@2472: 
tonyp@2472: protected:
tonyp@2643:   virtual void fill_in_ext_msg_extra(hrs_ext_msg* msg);
tonyp@2472: 
tonyp@2472:   // See the comment for HeapRegionSetBase::clear()
tonyp@2472:   virtual void clear();
tonyp@2472: 
brutisso@6385: public:
brutisso@6385:   FreeRegionList(const char* name, HRSMtSafeChecker* mt_safety_checker = NULL):
brutisso@6385:     HeapRegionSetBase(name, false /* humongous */, true /* empty */, mt_safety_checker) {
tonyp@2472:     clear();
tonyp@2472:   }
tonyp@2472: 
brutisso@6385:   void verify_list();
brutisso@6385: 
brutisso@6385:   HeapRegion* head() { return _head; }
brutisso@6385:   HeapRegion* tail() { return _tail; }
brutisso@6385: 
brutisso@6385:   static void set_unrealistically_long_length(uint len);
brutisso@6385: 
tonyp@2714:   // It adds hr to the list as the new head. The region should not be
tonyp@2714:   // a member of another set.
tonyp@2714:   inline void add_as_head(HeapRegion* hr);
tonyp@2714: 
tonyp@2472:   // It adds hr to the list as the new tail. The region should not be
tonyp@2472:   // a member of another set.
tonyp@2472:   inline void add_as_tail(HeapRegion* hr);
tonyp@2472: 
tonyp@2472:   // It removes and returns the head of the list. It assumes that the
tonyp@2472:   // list is not empty so it will return a non-NULL value.
tonyp@2472:   inline HeapRegion* remove_head();
tonyp@2472: 
tonyp@2472:   // Convenience method.
tonyp@2472:   inline HeapRegion* remove_head_or_null();
tonyp@2472: 
tonyp@2472:   // It moves the regions from from_list to this list and empties
tonyp@2472:   // from_list. The new regions will appear in the same order as they
tonyp@2714:   // were in from_list and be linked in the beginning of this list.
brutisso@6385:   void add_as_head(FreeRegionList* from_list);
tonyp@2714: 
tonyp@2714:   // It moves the regions from from_list to this list and empties
tonyp@2714:   // from_list. The new regions will appear in the same order as they
tonyp@2472:   // were in from_list and be linked in the end of this list.
brutisso@6385:   void add_as_tail(FreeRegionList* from_list);
tonyp@2472: 
tonyp@2472:   // It empties the list by removing all regions from it.
tonyp@2472:   void remove_all();
tonyp@2472: 
tonyp@2472:   // It removes all regions in the list that are pending for removal
tonyp@2472:   // (i.e., they have been tagged with "pending_removal"). The list
tonyp@2472:   // must not be empty, target_count should reflect the exact number
tonyp@2472:   // of regions that are pending for removal in the list, and
tonyp@2472:   // target_count should be > 1 (currently, we never need to remove a
tonyp@2472:   // single region using this).
tonyp@3713:   void remove_all_pending(uint target_count);
tonyp@2472: 
tonyp@2472:   virtual void verify();
tonyp@2472: 
tonyp@2472:   virtual void print_on(outputStream* out, bool print_contents = false);
tonyp@2472: };
tonyp@2472: 
tonyp@2643: // Iterator class that provides a convenient way to iterate over the
tonyp@2643: // regions of a HeapRegionLinkedList instance.
tonyp@2472: 
brutisso@6385: class FreeRegionListIterator : public StackObj {
tonyp@2472: private:
brutisso@6385:   FreeRegionList* _list;
tonyp@2472:   HeapRegion*           _curr;
tonyp@2472: 
tonyp@2472: public:
tonyp@2472:   bool more_available() {
tonyp@2472:     return _curr != NULL;
tonyp@2472:   }
tonyp@2472: 
tonyp@2472:   HeapRegion* get_next() {
tonyp@2472:     assert(more_available(),
tonyp@2472:            "get_next() should be called when more regions are available");
tonyp@2472: 
tonyp@2472:     // If we are going to introduce a count in the iterator we should
tonyp@2472:     // do the "cycle" check.
tonyp@2472: 
tonyp@2472:     HeapRegion* hr = _curr;
brutisso@6385:     _list->verify_region(hr);
tonyp@2472:     _curr = hr->next();
tonyp@2472:     return hr;
tonyp@2472:   }
tonyp@2472: 
brutisso@6385:   FreeRegionListIterator(FreeRegionList* list)
tonyp@2472:     : _curr(NULL), _list(list) {
tonyp@2472:     _curr = list->head();
tonyp@2472:   }
tonyp@2472: };
tonyp@2472: 
tonyp@2472: #endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP