jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/g1/heapRegionSet.hpp@1216415d8e35 (annotated)

src/share/vm/gc_implementation/g1/heapRegionSet.hpp@1216415d8e35 (annotated)

src/share/vm/gc_implementation/g1/heapRegionSet.hpp

Fri, 04 Mar 2011 17:13:19 -0500

author: tonyp
date: Fri, 04 Mar 2011 17:13:19 -0500
changeset 2643: 1216415d8e35
parent 2472: 0fa27f37d4d4
child 2714: 455328d90876
permissions: -rw-r--r--

7014923: G1: code cleanup
Summary: Some G1 code cleanup.
Reviewed-by: johnc, jcoomes, jwilhelm

 /*
  * copyright (c) 2011, 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_IMPLEMENTATION_G1_HEAPREGIONSET_HPP
 #define SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP
 #include "gc_implementation/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
 //////////////////// HeapRegionSetBase ////////////////////
 // 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 hrs_ext_msg;
 class HeapRegionSetBase VALUE_OBJ_CLASS_SPEC {
   friend class hrs_ext_msg;
 protected:
   static size_t calculate_region_num(HeapRegion* hr);
   static size_t _unrealistically_long_length;
   // 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.
   size_t _length;
   // The total number of regions represented by the set. If the set
   // does not contain humongous regions, this should be the same as
   // _length. If the set contains only humongous regions, this will
   // include the 'continues humongous' regions.
   size_t _region_num;
   // We don't keep track of the total capacity explicitly, we instead
   // recalculate it based on _region_num and the heap region size.
   // The sum of used bytes in the all the regions in the set.
   size_t _total_used_bytes;
   const char* _name;
   bool        _verify_in_progress;
   size_t      _calc_length;
   size_t      _calc_region_num;
   size_t      _calc_total_capacity_bytes;
   size_t      _calc_total_used_bytes;
   // verify_region() is used to ensure that the contents of a region
   // added to / removed from a set are consistent. Different sets
   // make different assumptions about the regions added to them. So
   // each set can override verify_region_extra(), which is called
   // from verify_region(), and do any extra verification it needs to
   // perform in that.
   virtual const char* verify_region_extra(HeapRegion* hr) { return NULL; }
   bool verify_region(HeapRegion* hr,
                      HeapRegionSetBase* expected_containing_set);
   // Indicates whether all regions in the set should be humongous or
   // not. Only used during verification.
   virtual bool regions_humongous() = 0;
   // Indicates whether all regions in the set should be empty or
   // not. Only used during verification.
   virtual bool regions_empty() = 0;
   // Subclasses can optionally override this to do MT safety protocol
   // checks. It is called in an assert from all methods that perform
   // updates on the set (and subclasses should also call it too).
   virtual bool check_mt_safety() { return true; }
   // 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.
   virtual void fill_in_ext_msg_extra(hrs_ext_msg* msg) { }
   void fill_in_ext_msg(hrs_ext_msg* msg, const char* message);
   // It updates the fields of the set to reflect hr being added to
   // the set.
   inline void update_for_addition(HeapRegion* hr);
   // It updates the fields of the set to reflect hr being added to
   // the set and tags the region appropriately.
   inline void add_internal(HeapRegion* hr);
   // It updates the fields of the set to reflect hr being removed
   // from the set.
   inline void update_for_removal(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_internal(HeapRegion* hr);
   // It clears all the fields of the sets. Note: it will not iterate
   // over the set and remove regions from it. It assumes that the
   // caller has already done so. It will literally just clear the fields.
   virtual void clear();
   HeapRegionSetBase(const char* name);
 public:
   static void set_unrealistically_long_length(size_t len);
   const char* name() { return _name; }
   size_t length() { return _length; }
   bool is_empty() { return _length == 0; }
   size_t region_num() { return _region_num; }
   size_t total_capacity_bytes() {
     return region_num() << HeapRegion::LogOfHRGrainBytes;
   }
   size_t total_used_bytes() { return _total_used_bytes; }
   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("") {
     set->fill_in_ext_msg(this, message);
   }
 };
 // These two macros are provided for convenience, to keep the uses of
 // these two asserts a bit more concise.
 #define hrs_assert_mt_safety_ok(_set_)                                        \
   do {                                                                        \
     assert((_set_)->check_mt_safety(), hrs_ext_msg((_set_), "MT safety"));    \
   } while (0)
 #define hrs_assert_region_ok(_set_, _hr_, _expected_)                         \
   do {                                                                        \
     assert((_set_)->verify_region((_hr_), (_expected_)),                      \
            hrs_ext_msg((_set_), "region verification"));                      \
   } while (0)
 //////////////////// HeapRegionSet ////////////////////
 #define hrs_assert_sets_match(_set1_, _set2_)                                 \
   do {                                                                        \
     assert(((_set1_)->regions_humongous() ==                                  \
                                             (_set2_)->regions_humongous()) && \
            ((_set1_)->regions_empty() == (_set2_)->regions_empty()),          \
            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 {
 protected:
   virtual const char* verify_region_extra(HeapRegion* hr) {
     if (hr->next() != NULL) {
       return "next() should always be NULL as we do not link the regions";
     }
     return HeapRegionSetBase::verify_region_extra(hr);
   }
   HeapRegionSet(const char* name) : HeapRegionSetBase(name) {
     clear();
   }
 public:
   // It adds hr to the set. The region should not be a member of
   // another set.
   inline void add(HeapRegion* hr);
   // It removes hr from the set. The region should be a member of
   // this set.
   inline void remove(HeapRegion* hr);
   // It removes a region from the set. Instead of updating the fields
   // of the set to reflect this removal, it accumulates the updates
   // in proxy_set. The idea is that proxy_set is thread-local to
   // avoid multiple threads updating the fields of the set
   // concurrently and having to synchronize. The method
   // update_from_proxy() will update the fields of the set from the
   // proxy_set.
   inline void remove_with_proxy(HeapRegion* hr, HeapRegionSet* proxy_set);
   // After multiple calls to remove_with_proxy() the updates to the
   // fields of the set are accumulated in proxy_set. This call
   // updates the fields of the set from proxy_set.
   void update_from_proxy(HeapRegionSet* proxy_set);
 };
 //////////////////// HeapRegionLinkedList ////////////////////
 // A set that links all the regions added to it in a singly-linked
 // 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. All
 // those operations are done in constant time.
 class HeapRegionLinkedListIterator;
 class HeapRegionLinkedList : public HeapRegionSetBase {
   friend class HeapRegionLinkedListIterator;
 private:
   HeapRegion* _head;
   HeapRegion* _tail;
   // These are provided for use by the friend classes.
   HeapRegion* head() { return _head; }
   HeapRegion* tail() { return _tail; }
 protected:
   virtual void fill_in_ext_msg_extra(hrs_ext_msg* msg);
   // See the comment for HeapRegionSetBase::clear()
   virtual void clear();
   HeapRegionLinkedList(const char* name) : HeapRegionSetBase(name) {
     clear();
   }
 public:
   // It adds hr to the list as the new tail. The region should not be
   // a member of another set.
   inline void add_as_tail(HeapRegion* hr);
   // It removes and returns the head of the list. It assumes that the
   // list is not empty so it will return a non-NULL value.
   inline HeapRegion* remove_head();
   // Convenience method.
   inline HeapRegion* remove_head_or_null();
   // It moves the regions from from_list to this list and empties
   // from_list. The new regions will appear in the same order as they
   // were in from_list and be linked in the end of this list.
   void add_as_tail(HeapRegionLinkedList* from_list);
   // It empties the list by removing all regions from it.
   void remove_all();
   // It removes all regions in the list that are pending for removal
   // (i.e., they have been tagged with "pending_removal"). The list
   // must not be empty, target_count should reflect the exact number
   // of regions that are pending for removal in the list, and
   // target_count should be > 1 (currently, we never need to remove a
   // single region using this).
   void remove_all_pending(size_t target_count);
   virtual void verify();
   virtual void print_on(outputStream* out, bool print_contents = false);
 };
 //////////////////// HeapRegionLinkedListIterator ////////////////////
 // Iterator class that provides a convenient way to iterate over the
 // regions of a HeapRegionLinkedList instance.
 class HeapRegionLinkedListIterator : public StackObj {
 private:
   HeapRegionLinkedList* _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;
     assert(_list->verify_region(hr, _list), "region verification");
     _curr = hr->next();
     return hr;
   }
   HeapRegionLinkedListIterator(HeapRegionLinkedList* list)
     : _curr(NULL), _list(list) {
     _curr = list->head();
   }
 };
 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/g1/heapRegionSet.hpp@1216415d8e35 (annotated)

src/share/vm/gc_implementation/g1/heapRegionSet.hpp