parOopClosures.inline.hpp revision 8413:92457dfb91bd 
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24
25#ifndef SHARE_VM_GC_CMS_PAROOPCLOSURES_INLINE_HPP
26#define SHARE_VM_GC_CMS_PAROOPCLOSURES_INLINE_HPP
27
28#include "gc/cms/parNewGeneration.hpp"
29#include "gc/cms/parOopClosures.hpp"
30#include "gc/shared/cardTableRS.hpp"
31#include "gc/shared/genCollectedHeap.hpp"
32#include "gc/shared/genOopClosures.inline.hpp"
33
34template <class T> inline void ParScanWeakRefClosure::do_oop_work(T* p) {
35  assert (!oopDesc::is_null(*p), "null weak reference?");
36  oop obj = oopDesc::load_decode_heap_oop_not_null(p);
37  // weak references are sometimes scanned twice; must check
38  // that to-space doesn't already contain this object
39  if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) {
40    // we need to ensure that it is copied (see comment in
41    // ParScanClosure::do_oop_work).
42    Klass* objK = obj->klass();
43    markOop m = obj->mark();
44    oop new_obj;
45    if (m->is_marked()) { // Contains forwarding pointer.
46      new_obj = ParNewGeneration::real_forwardee(obj);
47    } else {
48      size_t obj_sz = obj->size_given_klass(objK);
49      new_obj = ((ParNewGeneration*)_g)->copy_to_survivor_space(_par_scan_state,
50                                                                obj, obj_sz, m);
51    }
52    oopDesc::encode_store_heap_oop_not_null(p, new_obj);
53  }
54}
55
56inline void ParScanWeakRefClosure::do_oop_nv(oop* p)       { ParScanWeakRefClosure::do_oop_work(p); }
57inline void ParScanWeakRefClosure::do_oop_nv(narrowOop* p) { ParScanWeakRefClosure::do_oop_work(p); }
58
59template <class T> inline void ParScanClosure::par_do_barrier(T* p) {
60  assert(generation()->is_in_reserved(p), "expected ref in generation");
61  assert(!oopDesc::is_null(*p), "expected non-null object");
62  oop obj = oopDesc::load_decode_heap_oop_not_null(p);
63  // If p points to a younger generation, mark the card.
64  if ((HeapWord*)obj < gen_boundary()) {
65    rs()->write_ref_field_gc_par(p, obj);
66  }
67}
68
69template <class T>
70inline void ParScanClosure::do_oop_work(T* p,
71                                        bool gc_barrier,
72                                        bool root_scan) {
73  assert((!GenCollectedHeap::heap()->is_in_reserved(p) ||
74          generation()->is_in_reserved(p))
75         && (generation()->level() == 0 || gc_barrier),
76         "The gen must be right, and we must be doing the barrier "
77         "in older generations.");
78  T heap_oop = oopDesc::load_heap_oop(p);
79  if (!oopDesc::is_null(heap_oop)) {
80    oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
81    if ((HeapWord*)obj < _boundary) {
82#ifndef PRODUCT
83      if (_g->to()->is_in_reserved(obj)) {
84        tty->print_cr("Scanning field (" PTR_FORMAT ") twice?", p2i(p));
85        GenCollectedHeap* gch = GenCollectedHeap::heap();
86        Space* sp = gch->space_containing(p);
87        oop obj = oop(sp->block_start(p));
88        assert((HeapWord*)obj < (HeapWord*)p, "Error");
89        tty->print_cr("Object: " PTR_FORMAT, p2i((void *)obj));
90        tty->print_cr("-------");
91        obj->print();
92        tty->print_cr("-----");
93        tty->print_cr("Heap:");
94        tty->print_cr("-----");
95        gch->print();
96        ShouldNotReachHere();
97      }
98#endif
99      // OK, we need to ensure that it is copied.
100      // We read the klass and mark in this order, so that we can reliably
101      // get the size of the object: if the mark we read is not a
102      // forwarding pointer, then the klass is valid: the klass is only
103      // overwritten with an overflow next pointer after the object is
104      // forwarded.
105      Klass* objK = obj->klass();
106      markOop m = obj->mark();
107      oop new_obj;
108      if (m->is_marked()) { // Contains forwarding pointer.
109        new_obj = ParNewGeneration::real_forwardee(obj);
110        oopDesc::encode_store_heap_oop_not_null(p, new_obj);
111#ifndef PRODUCT
112        if (TraceScavenge) {
113          gclog_or_tty->print_cr("{%s %s ( " PTR_FORMAT " ) " PTR_FORMAT " -> " PTR_FORMAT " (%d)}",
114             "forwarded ",
115             new_obj->klass()->internal_name(), p2i(p), p2i((void *)obj), p2i((void *)new_obj), new_obj->size());
116        }
117#endif
118
119      } else {
120        size_t obj_sz = obj->size_given_klass(objK);
121        new_obj = _g->copy_to_survivor_space(_par_scan_state, obj, obj_sz, m);
122        oopDesc::encode_store_heap_oop_not_null(p, new_obj);
123        if (root_scan) {
124          // This may have pushed an object.  If we have a root
125          // category with a lot of roots, can't let the queue get too
126          // full:
127          (void)_par_scan_state->trim_queues(10 * ParallelGCThreads);
128        }
129      }
130      if (is_scanning_a_klass()) {
131        do_klass_barrier();
132      } else if (gc_barrier) {
133        // Now call parent closure
134        par_do_barrier(p);
135      }
136    }
137  }
138}
139
140inline void ParScanWithBarrierClosure::do_oop_nv(oop* p)       { ParScanClosure::do_oop_work(p, true, false); }
141inline void ParScanWithBarrierClosure::do_oop_nv(narrowOop* p) { ParScanClosure::do_oop_work(p, true, false); }
142
143inline void ParScanWithoutBarrierClosure::do_oop_nv(oop* p)       { ParScanClosure::do_oop_work(p, false, false); }
144inline void ParScanWithoutBarrierClosure::do_oop_nv(narrowOop* p) { ParScanClosure::do_oop_work(p, false, false); }
145
146#endif // SHARE_VM_GC_CMS_PAROOPCLOSURES_INLINE_HPP
147