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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,
  68                                                       size_t obj_size,
  69                                                       uint age, bool tenured,
  70                                                       const PSPromotionLAB* lab) {
  71   // Skip if memory allocation failed
  72   if (new_obj != NULL) {
  73     const ParallelScavengeTracer* gc_tracer = PSScavenge::gc_tracer();
  74 
  75     if (lab != NULL) {
  76       // Promotion of object through newly allocated PLAB
  77       if (gc_tracer->should_report_promotion_in_new_plab_event()) {
  78         size_t obj_bytes = obj_size * HeapWordSize;
  79         size_t lab_size = lab->capacity();
  80         gc_tracer->report_promotion_in_new_plab_event(old_obj->klass(), obj_bytes,
  81                                                       age, tenured, lab_size);
  82       }
  83     } else {
  84       // Promotion of object directly to heap
  85       if (gc_tracer->should_report_promotion_outside_plab_event()) {
  86         size_t obj_bytes = obj_size * HeapWordSize;
  87         gc_tracer->report_promotion_outside_plab_event(old_obj->klass(), obj_bytes,
  88                                                        age, tenured);
  89       }
  90     }
  91   }
  92 }
  93 
  94 //
  95 // This method is pretty bulky. It would be nice to split it up
  96 // into smaller submethods, but we need to be careful not to hurt
  97 // performance.
  98 //
  99 template<bool promote_immediately>
 100 oop PSPromotionManager::copy_to_survivor_space(oop o) {
 101   assert(PSScavenge::should_scavenge(&o), "Sanity");
 102 
 103   oop new_obj = NULL;
 104 
 105   // NOTE! We must be very careful with any methods that access the mark
 106   // in o. There may be multiple threads racing on it, and it may be forwarded
 107   // at any time. Do not use oop methods for accessing the mark!
 108   markOop test_mark = o->mark();
 109 
 110   // The same test as "o->is_forwarded()"
 111   if (!test_mark->is_marked()) {
 112     bool new_obj_is_tenured = false;
 113     size_t new_obj_size = o->size();
 114 
 115     // Find the objects age, MT safe.
 116     uint age = (test_mark->has_displaced_mark_helper() /* o->has_displaced_mark() */) ?
 117       test_mark->displaced_mark_helper()->age() : test_mark->age();

 118 
 119     if (!promote_immediately) {
 120       // Try allocating obj in to-space (unless too old)
 121       if (age < PSScavenge::tenuring_threshold()) {
 122         new_obj = (oop) _young_lab.allocate(new_obj_size);
 123         if (new_obj == NULL && !_young_gen_is_full) {
 124           // Do we allocate directly, or flush and refill?
 125           if (new_obj_size > (YoungPLABSize / 2)) {
 126             // Allocate this object directly
 127             new_obj = (oop)young_space()->cas_allocate(new_obj_size);
 128             promotion_trace_event(new_obj, o, new_obj_size, age, false, NULL);
 129           } else {
 130             // Flush and fill
 131             _young_lab.flush();
 132 
 133             HeapWord* lab_base = young_space()->cas_allocate(YoungPLABSize);
 134             if (lab_base != NULL) {
 135               _young_lab.initialize(MemRegion(lab_base, YoungPLABSize));
 136               // Try the young lab allocation again.
 137               new_obj = (oop) _young_lab.allocate(new_obj_size);
 138               promotion_trace_event(new_obj, o, new_obj_size, age, false, &_young_lab);
 139             } else {
 140               _young_gen_is_full = true;
 141             }
 142           }
 143         }
 144       }
 145     }
 146 
 147     // Otherwise try allocating obj tenured
 148     if (new_obj == NULL) {
 149 #ifndef PRODUCT
 150       if (Universe::heap()->promotion_should_fail()) {
 151         return oop_promotion_failed(o, test_mark);
 152       }
 153 #endif  // #ifndef PRODUCT
 154 
 155       new_obj = (oop) _old_lab.allocate(new_obj_size);
 156       new_obj_is_tenured = true;
 157 
 158       if (new_obj == NULL) {
 159         if (!_old_gen_is_full) {
 160           // Do we allocate directly, or flush and refill?
 161           if (new_obj_size > (OldPLABSize / 2)) {
 162             // Allocate this object directly
 163             new_obj = (oop)old_gen()->cas_allocate(new_obj_size);
 164             promotion_trace_event(new_obj, o, new_obj_size, age, true, NULL);
 165           } else {
 166             // Flush and fill
 167             _old_lab.flush();
 168 
 169             HeapWord* lab_base = old_gen()->cas_allocate(OldPLABSize);
 170             if(lab_base != NULL) {
 171 #ifdef ASSERT
 172               // Delay the initialization of the promotion lab (plab).
 173               // This exposes uninitialized plabs to card table processing.
 174               if (GCWorkerDelayMillis > 0) {
 175                 os::sleep(Thread::current(), GCWorkerDelayMillis, false);
 176               }
 177 #endif
 178               _old_lab.initialize(MemRegion(lab_base, OldPLABSize));
 179               // Try the old lab allocation again.
 180               new_obj = (oop) _old_lab.allocate(new_obj_size);
 181               promotion_trace_event(new_obj, o, new_obj_size, age, true, &_old_lab);
 182             }
 183           }
 184         }
 185 
 186         // This is the promotion failed test, and code handling.
 187         // The code belongs here for two reasons. It is slightly
 188         // different than the code below, and cannot share the
 189         // CAS testing code. Keeping the code here also minimizes
 190         // the impact on the common case fast path code.
 191 
 192         if (new_obj == NULL) {
 193           _old_gen_is_full = true;
 194           return oop_promotion_failed(o, test_mark);
 195         }
 196       }
 197     }
 198 
 199     assert(new_obj != NULL, "allocation should have succeeded");
 200 
 201     // Copy obj


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