Thu, 21 Aug 2014 16:44:41 +0200
8055098: WB API should be extended to provide information about size and age of object.
Summary: Extend the WhiteBox API to provide information about the size and age of objects. Further add a mechanism to trigger a young GC.
Reviewed-by: tschatzl, sjohanss
Contributed-by: Leonid Mesnik <leonid.mesnik@oracle.com>
tonyp@2472 | 1 | /* |
jwilhelm@6422 | 2 | * Copyright (c) 2011, 2014, Oracle and/or its affiliates. All rights reserved. |
tonyp@2472 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
tonyp@2472 | 4 | * |
tonyp@2472 | 5 | * This code is free software; you can redistribute it and/or modify it |
tonyp@2472 | 6 | * under the terms of the GNU General Public License version 2 only, as |
tonyp@2472 | 7 | * published by the Free Software Foundation. |
tonyp@2472 | 8 | * |
tonyp@2472 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
tonyp@2472 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
tonyp@2472 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
tonyp@2472 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
tonyp@2472 | 13 | * accompanied this code). |
tonyp@2472 | 14 | * |
tonyp@2472 | 15 | * You should have received a copy of the GNU General Public License version |
tonyp@2472 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
tonyp@2472 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
tonyp@2472 | 18 | * |
tonyp@2472 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
tonyp@2472 | 20 | * or visit www.oracle.com if you need additional information or have any |
tonyp@2472 | 21 | * questions. |
tonyp@2472 | 22 | * |
tonyp@2472 | 23 | */ |
tonyp@2472 | 24 | |
tonyp@2472 | 25 | #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP |
tonyp@2472 | 26 | #define SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP |
tonyp@2472 | 27 | |
tonyp@2472 | 28 | #include "gc_implementation/g1/heapRegion.hpp" |
tonyp@2472 | 29 | |
tonyp@2472 | 30 | // Large buffer for some cases where the output might be larger than normal. |
tonyp@2643 | 31 | #define HRS_ERR_MSG_BUFSZ 512 |
tonyp@2643 | 32 | typedef FormatBuffer<HRS_ERR_MSG_BUFSZ> hrs_err_msg; |
tonyp@2472 | 33 | |
tonyp@2472 | 34 | // Set verification will be forced either if someone defines |
tonyp@2472 | 35 | // HEAP_REGION_SET_FORCE_VERIFY to be 1, or in builds in which |
tonyp@2472 | 36 | // asserts are compiled in. |
tonyp@2472 | 37 | #ifndef HEAP_REGION_SET_FORCE_VERIFY |
tonyp@2472 | 38 | #define HEAP_REGION_SET_FORCE_VERIFY defined(ASSERT) |
tonyp@2472 | 39 | #endif // HEAP_REGION_SET_FORCE_VERIFY |
tonyp@2472 | 40 | |
brutisso@6385 | 41 | class hrs_ext_msg; |
brutisso@6385 | 42 | |
brutisso@6385 | 43 | class HRSMtSafeChecker : public CHeapObj<mtGC> { |
brutisso@6385 | 44 | public: |
brutisso@6385 | 45 | virtual void check() = 0; |
brutisso@6385 | 46 | }; |
brutisso@6385 | 47 | |
brutisso@6385 | 48 | class MasterFreeRegionListMtSafeChecker : public HRSMtSafeChecker { public: void check(); }; |
brutisso@6385 | 49 | class SecondaryFreeRegionListMtSafeChecker : public HRSMtSafeChecker { public: void check(); }; |
brutisso@6385 | 50 | class HumongousRegionSetMtSafeChecker : public HRSMtSafeChecker { public: void check(); }; |
brutisso@6385 | 51 | class OldRegionSetMtSafeChecker : public HRSMtSafeChecker { public: void check(); }; |
brutisso@6385 | 52 | |
brutisso@6385 | 53 | class HeapRegionSetCount VALUE_OBJ_CLASS_SPEC { |
brutisso@6385 | 54 | friend class VMStructs; |
brutisso@6385 | 55 | uint _length; |
brutisso@6385 | 56 | size_t _capacity; |
brutisso@6385 | 57 | |
brutisso@6385 | 58 | public: |
brutisso@6385 | 59 | HeapRegionSetCount() : _length(0), _capacity(0) { } |
brutisso@6385 | 60 | |
brutisso@6385 | 61 | const uint length() const { return _length; } |
brutisso@6385 | 62 | const size_t capacity() const { return _capacity; } |
brutisso@6385 | 63 | |
brutisso@6385 | 64 | void increment(uint length_to_add, size_t capacity_to_add) { |
brutisso@6385 | 65 | _length += length_to_add; |
brutisso@6385 | 66 | _capacity += capacity_to_add; |
brutisso@6385 | 67 | } |
brutisso@6385 | 68 | |
brutisso@6385 | 69 | void decrement(const uint length_to_remove, const size_t capacity_to_remove) { |
brutisso@6385 | 70 | _length -= length_to_remove; |
brutisso@6385 | 71 | _capacity -= capacity_to_remove; |
brutisso@6385 | 72 | } |
brutisso@6385 | 73 | }; |
tonyp@2472 | 74 | |
tonyp@2472 | 75 | // Base class for all the classes that represent heap region sets. It |
tonyp@2472 | 76 | // contains the basic attributes that each set needs to maintain |
tonyp@2472 | 77 | // (e.g., length, region num, used bytes sum) plus any shared |
tonyp@2472 | 78 | // functionality (e.g., verification). |
tonyp@2472 | 79 | |
tonyp@2472 | 80 | class HeapRegionSetBase VALUE_OBJ_CLASS_SPEC { |
tonyp@3457 | 81 | friend class VMStructs; |
brutisso@6385 | 82 | private: |
brutisso@6385 | 83 | bool _is_humongous; |
brutisso@6385 | 84 | bool _is_empty; |
brutisso@6385 | 85 | HRSMtSafeChecker* _mt_safety_checker; |
tonyp@2472 | 86 | |
tonyp@2472 | 87 | protected: |
tonyp@2472 | 88 | // The number of regions added to the set. If the set contains |
tonyp@2472 | 89 | // only humongous regions, this reflects only 'starts humongous' |
tonyp@2472 | 90 | // regions and does not include 'continues humongous' ones. |
brutisso@6385 | 91 | HeapRegionSetCount _count; |
tonyp@2472 | 92 | |
tonyp@2472 | 93 | const char* _name; |
tonyp@2472 | 94 | |
brutisso@6385 | 95 | bool _verify_in_progress; |
tonyp@3268 | 96 | |
tonyp@2472 | 97 | // verify_region() is used to ensure that the contents of a region |
brutisso@6385 | 98 | // added to / removed from a set are consistent. |
brutisso@6385 | 99 | void verify_region(HeapRegion* hr) PRODUCT_RETURN; |
tonyp@2472 | 100 | |
tonyp@2472 | 101 | // Indicates whether all regions in the set should be humongous or |
tonyp@2472 | 102 | // not. Only used during verification. |
brutisso@6385 | 103 | bool regions_humongous() { return _is_humongous; } |
tonyp@2472 | 104 | |
tonyp@2472 | 105 | // Indicates whether all regions in the set should be empty or |
tonyp@2472 | 106 | // not. Only used during verification. |
brutisso@6385 | 107 | bool regions_empty() { return _is_empty; } |
tonyp@2472 | 108 | |
brutisso@6385 | 109 | void check_mt_safety() { |
brutisso@6385 | 110 | if (_mt_safety_checker != NULL) { |
brutisso@6385 | 111 | _mt_safety_checker->check(); |
brutisso@6385 | 112 | } |
brutisso@6385 | 113 | } |
brutisso@6385 | 114 | |
brutisso@6385 | 115 | virtual void fill_in_ext_msg_extra(hrs_ext_msg* msg) { } |
brutisso@6385 | 116 | |
brutisso@6385 | 117 | HeapRegionSetBase(const char* name, bool humongous, bool empty, HRSMtSafeChecker* mt_safety_checker); |
brutisso@6385 | 118 | |
brutisso@6385 | 119 | public: |
brutisso@6385 | 120 | const char* name() { return _name; } |
brutisso@6385 | 121 | |
tschatzl@7009 | 122 | uint length() const { return _count.length(); } |
brutisso@6385 | 123 | |
brutisso@6385 | 124 | bool is_empty() { return _count.length() == 0; } |
brutisso@6385 | 125 | |
brutisso@6385 | 126 | size_t total_capacity_bytes() { |
brutisso@6385 | 127 | return _count.capacity(); |
brutisso@6385 | 128 | } |
brutisso@6385 | 129 | |
brutisso@6385 | 130 | // It updates the fields of the set to reflect hr being added to |
brutisso@6385 | 131 | // the set and tags the region appropriately. |
brutisso@6385 | 132 | inline void add(HeapRegion* hr); |
brutisso@6385 | 133 | |
brutisso@6385 | 134 | // It updates the fields of the set to reflect hr being removed |
brutisso@6385 | 135 | // from the set and tags the region appropriately. |
brutisso@6385 | 136 | inline void remove(HeapRegion* hr); |
tonyp@2472 | 137 | |
tonyp@2472 | 138 | // fill_in_ext_msg() writes the the values of the set's attributes |
tonyp@2643 | 139 | // in the custom err_msg (hrs_ext_msg). fill_in_ext_msg_extra() |
tonyp@2472 | 140 | // allows subclasses to append further information. |
tonyp@2643 | 141 | void fill_in_ext_msg(hrs_ext_msg* msg, const char* message); |
tonyp@2472 | 142 | |
tonyp@2472 | 143 | virtual void verify(); |
tonyp@2472 | 144 | void verify_start(); |
tonyp@2472 | 145 | void verify_next_region(HeapRegion* hr); |
tonyp@2472 | 146 | void verify_end(); |
tonyp@2472 | 147 | |
tonyp@2472 | 148 | #if HEAP_REGION_SET_FORCE_VERIFY |
tonyp@2472 | 149 | void verify_optional() { |
tonyp@2472 | 150 | verify(); |
tonyp@2472 | 151 | } |
tonyp@2472 | 152 | #else // HEAP_REGION_SET_FORCE_VERIFY |
tonyp@2472 | 153 | void verify_optional() { } |
tonyp@2472 | 154 | #endif // HEAP_REGION_SET_FORCE_VERIFY |
tonyp@2472 | 155 | |
tonyp@2472 | 156 | virtual void print_on(outputStream* out, bool print_contents = false); |
tonyp@2472 | 157 | }; |
tonyp@2472 | 158 | |
tonyp@2472 | 159 | // Customized err_msg for heap region sets. Apart from a |
tonyp@2472 | 160 | // assert/guarantee-specific message it also prints out the values of |
tonyp@2472 | 161 | // the fields of the associated set. This can be very helpful in |
tonyp@2472 | 162 | // diagnosing failures. |
tonyp@2643 | 163 | class hrs_ext_msg : public hrs_err_msg { |
tonyp@2472 | 164 | public: |
tschatzl@7050 | 165 | hrs_ext_msg(HeapRegionSetBase* set, const char* message) : hrs_err_msg("%s", "") { |
tonyp@2472 | 166 | set->fill_in_ext_msg(this, message); |
tonyp@2472 | 167 | } |
tonyp@2472 | 168 | }; |
tonyp@2472 | 169 | |
tonyp@2643 | 170 | #define hrs_assert_sets_match(_set1_, _set2_) \ |
tonyp@2472 | 171 | do { \ |
tonyp@2472 | 172 | assert(((_set1_)->regions_humongous() == \ |
tonyp@2472 | 173 | (_set2_)->regions_humongous()) && \ |
tonyp@2472 | 174 | ((_set1_)->regions_empty() == (_set2_)->regions_empty()), \ |
tonyp@2643 | 175 | hrs_err_msg("the contents of set %s and set %s should match", \ |
tonyp@2472 | 176 | (_set1_)->name(), (_set2_)->name())); \ |
tonyp@2472 | 177 | } while (0) |
tonyp@2472 | 178 | |
tonyp@2472 | 179 | // This class represents heap region sets whose members are not |
tonyp@2472 | 180 | // explicitly tracked. It's helpful to group regions using such sets |
tonyp@2472 | 181 | // so that we can reason about all the region groups in the heap using |
tonyp@2472 | 182 | // the same interface (namely, the HeapRegionSetBase API). |
tonyp@2472 | 183 | |
tonyp@2472 | 184 | class HeapRegionSet : public HeapRegionSetBase { |
brutisso@6385 | 185 | public: |
brutisso@6385 | 186 | HeapRegionSet(const char* name, bool humongous, HRSMtSafeChecker* mt_safety_checker): |
brutisso@6385 | 187 | HeapRegionSetBase(name, humongous, false /* empty */, mt_safety_checker) { } |
tonyp@2472 | 188 | |
brutisso@6385 | 189 | void bulk_remove(const HeapRegionSetCount& removed) { |
brutisso@6385 | 190 | _count.decrement(removed.length(), removed.capacity()); |
tonyp@2472 | 191 | } |
tonyp@2472 | 192 | }; |
tonyp@2472 | 193 | |
jwilhelm@6422 | 194 | // A set that links all the regions added to it in a doubly-linked |
tschatzl@7050 | 195 | // sorted list. We should try to avoid doing operations that iterate over |
tonyp@2472 | 196 | // such lists in performance critical paths. Typically we should |
tschatzl@7050 | 197 | // add / remove one region at a time or concatenate two lists. |
tonyp@2472 | 198 | |
brutisso@6385 | 199 | class FreeRegionListIterator; |
tonyp@2472 | 200 | |
brutisso@6385 | 201 | class FreeRegionList : public HeapRegionSetBase { |
brutisso@6385 | 202 | friend class FreeRegionListIterator; |
tonyp@2472 | 203 | |
tonyp@2472 | 204 | private: |
tonyp@2472 | 205 | HeapRegion* _head; |
tonyp@2472 | 206 | HeapRegion* _tail; |
tonyp@2472 | 207 | |
jwilhelm@6422 | 208 | // _last is used to keep track of where we added an element the last |
tschatzl@7050 | 209 | // time. It helps to improve performance when adding several ordered items in a row. |
jwilhelm@6422 | 210 | HeapRegion* _last; |
jwilhelm@6422 | 211 | |
brutisso@6385 | 212 | static uint _unrealistically_long_length; |
brutisso@6385 | 213 | |
tschatzl@7050 | 214 | inline HeapRegion* remove_from_head_impl(); |
tschatzl@7050 | 215 | inline HeapRegion* remove_from_tail_impl(); |
tonyp@2472 | 216 | |
tonyp@2472 | 217 | protected: |
tonyp@2643 | 218 | virtual void fill_in_ext_msg_extra(hrs_ext_msg* msg); |
tonyp@2472 | 219 | |
tonyp@2472 | 220 | // See the comment for HeapRegionSetBase::clear() |
tonyp@2472 | 221 | virtual void clear(); |
tonyp@2472 | 222 | |
brutisso@6385 | 223 | public: |
brutisso@6385 | 224 | FreeRegionList(const char* name, HRSMtSafeChecker* mt_safety_checker = NULL): |
brutisso@6385 | 225 | HeapRegionSetBase(name, false /* humongous */, true /* empty */, mt_safety_checker) { |
tonyp@2472 | 226 | clear(); |
tonyp@2472 | 227 | } |
tonyp@2472 | 228 | |
brutisso@6385 | 229 | void verify_list(); |
brutisso@6385 | 230 | |
tschatzl@7050 | 231 | #ifdef ASSERT |
tschatzl@7050 | 232 | bool contains(HeapRegion* hr) const { |
tschatzl@7050 | 233 | return hr->containing_set() == this; |
tschatzl@7050 | 234 | } |
tschatzl@7050 | 235 | #endif |
brutisso@6385 | 236 | |
brutisso@6385 | 237 | static void set_unrealistically_long_length(uint len); |
brutisso@6385 | 238 | |
jwilhelm@6422 | 239 | // Add hr to the list. The region should not be a member of another set. |
jwilhelm@6422 | 240 | // Assumes that the list is ordered and will preserve that order. The order |
jwilhelm@6422 | 241 | // is determined by hrs_index. |
jwilhelm@6422 | 242 | inline void add_ordered(HeapRegion* hr); |
jwilhelm@6422 | 243 | |
jwilhelm@6422 | 244 | // Removes from head or tail based on the given argument. |
tschatzl@7050 | 245 | HeapRegion* remove_region(bool from_head); |
jwilhelm@6422 | 246 | |
jwilhelm@6422 | 247 | // Merge two ordered lists. The result is also ordered. The order is |
jwilhelm@6422 | 248 | // determined by hrs_index. |
jwilhelm@6422 | 249 | void add_ordered(FreeRegionList* from_list); |
jwilhelm@6422 | 250 | |
tonyp@2472 | 251 | // It empties the list by removing all regions from it. |
tonyp@2472 | 252 | void remove_all(); |
tonyp@2472 | 253 | |
tschatzl@7050 | 254 | // Remove all (contiguous) regions from first to first + num_regions -1 from |
tschatzl@7050 | 255 | // this list. |
tschatzl@7050 | 256 | // Num_regions must be > 1. |
tschatzl@7050 | 257 | void remove_starting_at(HeapRegion* first, uint num_regions); |
tonyp@2472 | 258 | |
tonyp@2472 | 259 | virtual void verify(); |
tonyp@2472 | 260 | |
tonyp@2472 | 261 | virtual void print_on(outputStream* out, bool print_contents = false); |
tonyp@2472 | 262 | }; |
tonyp@2472 | 263 | |
tonyp@2643 | 264 | // Iterator class that provides a convenient way to iterate over the |
tschatzl@7050 | 265 | // regions of a FreeRegionList. |
tonyp@2472 | 266 | |
brutisso@6385 | 267 | class FreeRegionListIterator : public StackObj { |
tonyp@2472 | 268 | private: |
brutisso@6385 | 269 | FreeRegionList* _list; |
jwilhelm@6422 | 270 | HeapRegion* _curr; |
tonyp@2472 | 271 | |
tonyp@2472 | 272 | public: |
tonyp@2472 | 273 | bool more_available() { |
tonyp@2472 | 274 | return _curr != NULL; |
tonyp@2472 | 275 | } |
tonyp@2472 | 276 | |
tonyp@2472 | 277 | HeapRegion* get_next() { |
tonyp@2472 | 278 | assert(more_available(), |
tonyp@2472 | 279 | "get_next() should be called when more regions are available"); |
tonyp@2472 | 280 | |
tonyp@2472 | 281 | // If we are going to introduce a count in the iterator we should |
tonyp@2472 | 282 | // do the "cycle" check. |
tonyp@2472 | 283 | |
tonyp@2472 | 284 | HeapRegion* hr = _curr; |
brutisso@6385 | 285 | _list->verify_region(hr); |
tonyp@2472 | 286 | _curr = hr->next(); |
tonyp@2472 | 287 | return hr; |
tonyp@2472 | 288 | } |
tonyp@2472 | 289 | |
jwilhelm@6422 | 290 | FreeRegionListIterator(FreeRegionList* list) : _curr(NULL), _list(list) { |
tschatzl@7050 | 291 | _curr = list->_head; |
tonyp@2472 | 292 | } |
tonyp@2472 | 293 | }; |
tonyp@2472 | 294 | |
tonyp@2472 | 295 | #endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP |