src/share/vm/gc_implementation/parallelScavenge/psPromotionManager.inline.hpp

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  47       if (PSScavenge::is_obj_in_young(o)) {
  48         PSScavenge::card_table()->inline_write_ref_field_gc(p, o);
  49       }
  50       oopDesc::encode_store_heap_oop_not_null(p, o);
  51     } else {
  52       push_depth(p);
  53     }
  54   }
  55 }
  56 
  57 template <class T>
  58 inline void PSPromotionManager::claim_or_forward_depth(T* p) {
  59   assert(PSScavenge::should_scavenge(p, true), "revisiting object?");
  60   assert(Universe::heap()->kind() == CollectedHeap::ParallelScavengeHeap,
  61          "Sanity");
  62   assert(Universe::heap()->is_in(p), "pointer outside heap");
  63 
  64   claim_or_forward_internal_depth(p);
  65 }
  66 





















  67 //
  68 // This method is pretty bulky. It would be nice to split it up
  69 // into smaller submethods, but we need to be careful not to hurt
  70 // performance.
  71 //
  72 template<bool promote_immediately>
  73 oop PSPromotionManager::copy_to_survivor_space(oop o) {
  74   assert(PSScavenge::should_scavenge(&o), "Sanity");
  75 
  76   oop new_obj = NULL;
  77 
  78   // NOTE! We must be very careful with any methods that access the mark
  79   // in o. There may be multiple threads racing on it, and it may be forwarded
  80   // at any time. Do not use oop methods for accessing the mark!
  81   markOop test_mark = o->mark();
  82 
  83   // The same test as "o->is_forwarded()"
  84   if (!test_mark->is_marked()) {
  85     bool new_obj_is_tenured = false;
  86     size_t new_obj_size = o->size();
  87 
  88     if (!promote_immediately) {
  89       // Find the objects age, MT safe.
  90       uint age = (test_mark->has_displaced_mark_helper() /* o->has_displaced_mark() */) ?
  91         test_mark->displaced_mark_helper()->age() : test_mark->age();
  92 

  93       // Try allocating obj in to-space (unless too old)
  94       if (age < PSScavenge::tenuring_threshold()) {
  95         new_obj = (oop) _young_lab.allocate(new_obj_size);
  96         if (new_obj == NULL && !_young_gen_is_full) {
  97           // Do we allocate directly, or flush and refill?
  98           if (new_obj_size > (YoungPLABSize / 2)) {
  99             // Allocate this object directly
 100             new_obj = (oop)young_space()->cas_allocate(new_obj_size);

 101           } else {
 102             // Flush and fill
 103             _young_lab.flush();
 104 
 105             HeapWord* lab_base = young_space()->cas_allocate(YoungPLABSize);
 106             if (lab_base != NULL) {
 107               _young_lab.initialize(MemRegion(lab_base, YoungPLABSize));
 108               // Try the young lab allocation again.
 109               new_obj = (oop) _young_lab.allocate(new_obj_size);

 110             } else {
 111               _young_gen_is_full = true;
 112             }
 113           }
 114         }
 115       }
 116     }
 117 
 118     // Otherwise try allocating obj tenured
 119     if (new_obj == NULL) {
 120 #ifndef PRODUCT
 121       if (Universe::heap()->promotion_should_fail()) {
 122         return oop_promotion_failed(o, test_mark);
 123       }
 124 #endif  // #ifndef PRODUCT
 125 
 126       new_obj = (oop) _old_lab.allocate(new_obj_size);
 127       new_obj_is_tenured = true;
 128 
 129       if (new_obj == NULL) {
 130         if (!_old_gen_is_full) {
 131           // Do we allocate directly, or flush and refill?
 132           if (new_obj_size > (OldPLABSize / 2)) {
 133             // Allocate this object directly
 134             new_obj = (oop)old_gen()->cas_allocate(new_obj_size);

 135           } else {
 136             // Flush and fill
 137             _old_lab.flush();
 138 
 139             HeapWord* lab_base = old_gen()->cas_allocate(OldPLABSize);
 140             if(lab_base != NULL) {
 141 #ifdef ASSERT
 142               // Delay the initialization of the promotion lab (plab).
 143               // This exposes uninitialized plabs to card table processing.
 144               if (GCWorkerDelayMillis > 0) {
 145                 os::sleep(Thread::current(), GCWorkerDelayMillis, false);
 146               }
 147 #endif
 148               _old_lab.initialize(MemRegion(lab_base, OldPLABSize));
 149               // Try the old lab allocation again.
 150               new_obj = (oop) _old_lab.allocate(new_obj_size);

 151             }
 152           }
 153         }
 154 
 155         // This is the promotion failed test, and code handling.
 156         // The code belongs here for two reasons. It is slightly
 157         // different than the code below, and cannot share the
 158         // CAS testing code. Keeping the code here also minimizes
 159         // the impact on the common case fast path code.
 160 
 161         if (new_obj == NULL) {
 162           _old_gen_is_full = true;
 163           return oop_promotion_failed(o, test_mark);
 164         }
 165       }
 166     }
 167 
 168     assert(new_obj != NULL, "allocation should have succeeded");
 169 
 170     // Copy obj




  47       if (PSScavenge::is_obj_in_young(o)) {
  48         PSScavenge::card_table()->inline_write_ref_field_gc(p, o);
  49       }
  50       oopDesc::encode_store_heap_oop_not_null(p, o);
  51     } else {
  52       push_depth(p);
  53     }
  54   }
  55 }
  56 
  57 template <class T>
  58 inline void PSPromotionManager::claim_or_forward_depth(T* p) {
  59   assert(PSScavenge::should_scavenge(p, true), "revisiting object?");
  60   assert(Universe::heap()->kind() == CollectedHeap::ParallelScavengeHeap,
  61          "Sanity");
  62   assert(Universe::heap()->is_in(p), "pointer outside heap");
  63 
  64   claim_or_forward_internal_depth(p);
  65 }
  66 
  67 inline void PSPromotionManager::promotion_trace_event(oop new_obj, oop old_obj, size_t obj_size,
  68                                                       uint age, bool tenured,
  69                                                       const PSPromotionLAB* lab) {
  70   // Skip if memory allocation failed
  71   if (new_obj != NULL) {
  72     const ParallelScavengeTracer* gc_tracer = PSScavenge::gc_tracer();
  73 
  74     if (lab != NULL && gc_tracer->should_report_promotion_in_new_plab_event()) {
  75       // Promotion of small object in new PLAB
  76       size_t obj_bytes = obj_size * HeapWordSize;
  77       size_t lab_size = lab->capacity();
  78       gc_tracer->report_promotion_in_new_plab_event(old_obj->klass(), obj_bytes, age, tenured, lab_size);
  79 
  80     } else if (gc_tracer->should_report_promotion_outside_plab_event()) {
  81       // Promotion of object directly to heap without PLAB
  82       size_t obj_bytes = obj_size * HeapWordSize;
  83       gc_tracer->report_promotion_outside_plab_event(old_obj->klass(), obj_bytes, age, tenured);
  84     }
  85   }
  86 }
  87 
  88 //
  89 // This method is pretty bulky. It would be nice to split it up
  90 // into smaller submethods, but we need to be careful not to hurt
  91 // performance.
  92 //
  93 template<bool promote_immediately>
  94 oop PSPromotionManager::copy_to_survivor_space(oop o) {
  95   assert(PSScavenge::should_scavenge(&o), "Sanity");
  96 
  97   oop new_obj = NULL;
  98 
  99   // NOTE! We must be very careful with any methods that access the mark
 100   // in o. There may be multiple threads racing on it, and it may be forwarded
 101   // at any time. Do not use oop methods for accessing the mark!
 102   markOop test_mark = o->mark();
 103 
 104   // The same test as "o->is_forwarded()"
 105   if (!test_mark->is_marked()) {
 106     bool new_obj_is_tenured = false;
 107     size_t new_obj_size = o->size();
 108 

 109     // Find the objects age, MT safe.
 110     uint age = (test_mark->has_displaced_mark_helper() /* o->has_displaced_mark() */) ?
 111       test_mark->displaced_mark_helper()->age() : test_mark->age();
 112 
 113     if (!promote_immediately) {
 114       // Try allocating obj in to-space (unless too old)
 115       if (age < PSScavenge::tenuring_threshold()) {
 116         new_obj = (oop) _young_lab.allocate(new_obj_size);
 117         if (new_obj == NULL && !_young_gen_is_full) {
 118           // Do we allocate directly, or flush and refill?
 119           if (new_obj_size > (YoungPLABSize / 2)) {
 120             // Allocate this object directly
 121             new_obj = (oop)young_space()->cas_allocate(new_obj_size);
 122             promotion_trace_event(new_obj, o, new_obj_size, age, false, NULL);
 123           } else {
 124             // Flush and fill
 125             _young_lab.flush();
 126 
 127             HeapWord* lab_base = young_space()->cas_allocate(YoungPLABSize);
 128             if (lab_base != NULL) {
 129               _young_lab.initialize(MemRegion(lab_base, YoungPLABSize));
 130               // Try the young lab allocation again.
 131               new_obj = (oop) _young_lab.allocate(new_obj_size);
 132               promotion_trace_event(new_obj, o, new_obj_size, age, false, &_young_lab);
 133             } else {
 134               _young_gen_is_full = true;
 135             }
 136           }
 137         }
 138       }
 139     }
 140 
 141     // Otherwise try allocating obj tenured
 142     if (new_obj == NULL) {
 143 #ifndef PRODUCT
 144       if (Universe::heap()->promotion_should_fail()) {
 145         return oop_promotion_failed(o, test_mark);
 146       }
 147 #endif  // #ifndef PRODUCT
 148 
 149       new_obj = (oop) _old_lab.allocate(new_obj_size);
 150       new_obj_is_tenured = true;
 151 
 152       if (new_obj == NULL) {
 153         if (!_old_gen_is_full) {
 154           // Do we allocate directly, or flush and refill?
 155           if (new_obj_size > (OldPLABSize / 2)) {
 156             // Allocate this object directly
 157             new_obj = (oop)old_gen()->cas_allocate(new_obj_size);
 158             promotion_trace_event(new_obj, o, new_obj_size, age, true, NULL);
 159           } else {
 160             // Flush and fill
 161             _old_lab.flush();
 162 
 163             HeapWord* lab_base = old_gen()->cas_allocate(OldPLABSize);
 164             if(lab_base != NULL) {
 165 #ifdef ASSERT
 166               // Delay the initialization of the promotion lab (plab).
 167               // This exposes uninitialized plabs to card table processing.
 168               if (GCWorkerDelayMillis > 0) {
 169                 os::sleep(Thread::current(), GCWorkerDelayMillis, false);
 170               }
 171 #endif
 172               _old_lab.initialize(MemRegion(lab_base, OldPLABSize));
 173               // Try the old lab allocation again.
 174               new_obj = (oop) _old_lab.allocate(new_obj_size);
 175               promotion_trace_event(new_obj, o, new_obj_size, age, true, &_old_lab);
 176             }
 177           }
 178         }
 179 
 180         // This is the promotion failed test, and code handling.
 181         // The code belongs here for two reasons. It is slightly
 182         // different than the code below, and cannot share the
 183         // CAS testing code. Keeping the code here also minimizes
 184         // the impact on the common case fast path code.
 185 
 186         if (new_obj == NULL) {
 187           _old_gen_is_full = true;
 188           return oop_promotion_failed(o, test_mark);
 189         }
 190       }
 191     }
 192 
 193     assert(new_obj != NULL, "allocation should have succeeded");
 194 
 195     // Copy obj