src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp

Fri, 10 Jun 2011 13:16:40 -0400

author
tonyp
date
Fri, 10 Jun 2011 13:16:40 -0400
changeset 2963
c3f1170908be
parent 2715
abdfc822206f
child 3028
f44782f04dd4
permissions
-rw-r--r--

7045330: G1: Simplify/fix the HeapRegionSeq class
7042285: G1: native memory leak during humongous object allocation
6804436: G1: heap region indices should be size_t
Summary: A series of fixes and improvements to the HeapRegionSeq class: a) replace the _regions growable array with a standard C array, b) avoid de-allocating / re-allocating HeapRegion instances when the heap shrinks / grows (fix for 7042285), c) introduce fast method to map address to HeapRegion via a "biased" array pointer, d) embed the _hrs object in G1CollectedHeap, instead of pointing to it via an indirection, e) assume that all the regions added to the HeapRegionSeq instance are contiguous, f) replace int's with size_t's for indexes (and expand that to HeapRegion as part of 6804436), g) remove unnecessary / unused methods, h) rename a couple of fields (_alloc_search_start and _seq_bottom), i) fix iterate_from() not to always start from index 0 irrespective of the region passed to it, j) add a verification method to check the HeapRegionSeq assumptions, k) always call the wrappers for _hrs.iterate(), _hrs_length(), and _hrs.at() from G1CollectedHeap, not those methods directly, and l) unify the code that expands the sequence (by either re-using or creating a new HeapRegion) and make it robust wrt to a HeapRegion allocation failing.
Reviewed-by: stefank, johnc, brutisso

     1 /*
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     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
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    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    12  * version 2 for more details (a copy is included in the LICENSE file that
    13  * accompanied this code).
    14  *
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    18  *
    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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    25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_INLINE_HPP
    26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_INLINE_HPP
    28 #include "gc_implementation/g1/concurrentMark.hpp"
    29 #include "gc_implementation/g1/g1CollectedHeap.hpp"
    30 #include "gc_implementation/g1/g1AllocRegion.inline.hpp"
    31 #include "gc_implementation/g1/g1CollectorPolicy.hpp"
    32 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
    33 #include "utilities/taskqueue.hpp"
    35 // Inline functions for G1CollectedHeap
    37 template <class T>
    38 inline HeapRegion*
    39 G1CollectedHeap::heap_region_containing(const T addr) const {
    40   HeapRegion* hr = _hrs.addr_to_region((HeapWord*) addr);
    41   // hr can be null if addr in perm_gen
    42   if (hr != NULL && hr->continuesHumongous()) {
    43     hr = hr->humongous_start_region();
    44   }
    45   return hr;
    46 }
    48 template <class T>
    49 inline HeapRegion*
    50 G1CollectedHeap::heap_region_containing_raw(const T addr) const {
    51   assert(_g1_reserved.contains((const void*) addr), "invariant");
    52   HeapRegion* res = _hrs.addr_to_region_unsafe((HeapWord*) addr);
    53   return res;
    54 }
    56 inline bool G1CollectedHeap::obj_in_cs(oop obj) {
    57   HeapRegion* r = _hrs.addr_to_region((HeapWord*) obj);
    58   return r != NULL && r->in_collection_set();
    59 }
    61 inline HeapWord*
    62 G1CollectedHeap::attempt_allocation(size_t word_size,
    63                                     unsigned int* gc_count_before_ret) {
    64   assert_heap_not_locked_and_not_at_safepoint();
    65   assert(!isHumongous(word_size), "attempt_allocation() should not "
    66          "be called for humongous allocation requests");
    68   HeapWord* result = _mutator_alloc_region.attempt_allocation(word_size,
    69                                                       false /* bot_updates */);
    70   if (result == NULL) {
    71     result = attempt_allocation_slow(word_size, gc_count_before_ret);
    72   }
    73   assert_heap_not_locked();
    74   if (result != NULL) {
    75     dirty_young_block(result, word_size);
    76   }
    77   return result;
    78 }
    80 // It dirties the cards that cover the block so that so that the post
    81 // write barrier never queues anything when updating objects on this
    82 // block. It is assumed (and in fact we assert) that the block
    83 // belongs to a young region.
    84 inline void
    85 G1CollectedHeap::dirty_young_block(HeapWord* start, size_t word_size) {
    86   assert_heap_not_locked();
    88   // Assign the containing region to containing_hr so that we don't
    89   // have to keep calling heap_region_containing_raw() in the
    90   // asserts below.
    91   DEBUG_ONLY(HeapRegion* containing_hr = heap_region_containing_raw(start);)
    92   assert(containing_hr != NULL && start != NULL && word_size > 0,
    93          "pre-condition");
    94   assert(containing_hr->is_in(start), "it should contain start");
    95   assert(containing_hr->is_young(), "it should be young");
    96   assert(!containing_hr->isHumongous(), "it should not be humongous");
    98   HeapWord* end = start + word_size;
    99   assert(containing_hr->is_in(end - 1), "it should also contain end - 1");
   101   MemRegion mr(start, end);
   102   ((CardTableModRefBS*)_g1h->barrier_set())->dirty(mr);
   103 }
   105 inline RefToScanQueue* G1CollectedHeap::task_queue(int i) const {
   106   return _task_queues->queue(i);
   107 }
   109 inline  bool G1CollectedHeap::isMarkedPrev(oop obj) const {
   110   return _cm->prevMarkBitMap()->isMarked((HeapWord *)obj);
   111 }
   113 inline bool G1CollectedHeap::isMarkedNext(oop obj) const {
   114   return _cm->nextMarkBitMap()->isMarked((HeapWord *)obj);
   115 }
   117 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_INLINE_HPP

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