1 /*
2  * Copyright (C) 2014 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "zygote_space.h"
18 
19 #include "gc/accounting/card_table-inl.h"
20 #include "gc/accounting/space_bitmap-inl.h"
21 #include "gc/heap.h"
22 #include "thread-inl.h"
23 #include "utils.h"
24 
25 namespace art {
26 namespace gc {
27 namespace space {
28 
29 class CountObjectsAllocated {
30  public:
CountObjectsAllocated(size_t * objects_allocated)31   explicit CountObjectsAllocated(size_t* objects_allocated)
32       : objects_allocated_(objects_allocated) {}
33 
operator ()(mirror::Object * obj) const34   void operator()(mirror::Object* obj) const {
35     ++*objects_allocated_;
36   }
37 
38  private:
39   size_t* const objects_allocated_;
40 };
41 
Create(const std::string & name,MemMap * mem_map,accounting::ContinuousSpaceBitmap * live_bitmap,accounting::ContinuousSpaceBitmap * mark_bitmap)42 ZygoteSpace* ZygoteSpace::Create(const std::string& name, MemMap* mem_map,
43                                  accounting::ContinuousSpaceBitmap* live_bitmap,
44                                  accounting::ContinuousSpaceBitmap* mark_bitmap) {
45   DCHECK(live_bitmap != nullptr);
46   DCHECK(mark_bitmap != nullptr);
47   size_t objects_allocated = 0;
48   CountObjectsAllocated visitor(&objects_allocated);
49   ReaderMutexLock mu(Thread::Current(), *Locks::heap_bitmap_lock_);
50   live_bitmap->VisitMarkedRange(reinterpret_cast<uintptr_t>(mem_map->Begin()),
51                                 reinterpret_cast<uintptr_t>(mem_map->End()), visitor);
52   ZygoteSpace* zygote_space = new ZygoteSpace(name, mem_map, objects_allocated);
53   CHECK(zygote_space->live_bitmap_.get() == nullptr);
54   CHECK(zygote_space->mark_bitmap_.get() == nullptr);
55   zygote_space->live_bitmap_.reset(live_bitmap);
56   zygote_space->mark_bitmap_.reset(mark_bitmap);
57   return zygote_space;
58 }
59 
Clear()60 void ZygoteSpace::Clear() {
61   LOG(FATAL) << "Unimplemented";
62 }
63 
ZygoteSpace(const std::string & name,MemMap * mem_map,size_t objects_allocated)64 ZygoteSpace::ZygoteSpace(const std::string& name, MemMap* mem_map, size_t objects_allocated)
65     : ContinuousMemMapAllocSpace(name, mem_map, mem_map->Begin(), mem_map->End(), mem_map->End(),
66                                  kGcRetentionPolicyFullCollect),
67       objects_allocated_(objects_allocated) {
68 }
69 
Dump(std::ostream & os) const70 void ZygoteSpace::Dump(std::ostream& os) const {
71   os << GetType()
72       << " begin=" << reinterpret_cast<void*>(Begin())
73       << ",end=" << reinterpret_cast<void*>(End())
74       << ",size=" << PrettySize(Size())
75       << ",name=\"" << GetName() << "\"]";
76 }
77 
Alloc(Thread * self,size_t num_bytes,size_t * bytes_allocated,size_t * usable_size)78 mirror::Object* ZygoteSpace::Alloc(Thread* self, size_t num_bytes, size_t* bytes_allocated,
79                                    size_t* usable_size) {
80   UNIMPLEMENTED(FATAL);
81   return nullptr;
82 }
83 
AllocationSize(mirror::Object * obj,size_t * usable_size)84 size_t ZygoteSpace::AllocationSize(mirror::Object* obj, size_t* usable_size) {
85   UNIMPLEMENTED(FATAL);
86   return 0;
87 }
88 
Free(Thread * self,mirror::Object * ptr)89 size_t ZygoteSpace::Free(Thread* self, mirror::Object* ptr) {
90   UNIMPLEMENTED(FATAL);
91   return 0;
92 }
93 
FreeList(Thread * self,size_t num_ptrs,mirror::Object ** ptrs)94 size_t ZygoteSpace::FreeList(Thread* self, size_t num_ptrs, mirror::Object** ptrs) {
95   UNIMPLEMENTED(FATAL);
96   return 0;
97 }
98 
LogFragmentationAllocFailure(std::ostream &,size_t)99 void ZygoteSpace::LogFragmentationAllocFailure(std::ostream& /*os*/,
100                                                size_t /*failed_alloc_bytes*/) {
101   UNIMPLEMENTED(FATAL);
102 }
103 
SweepCallback(size_t num_ptrs,mirror::Object ** ptrs,void * arg)104 void ZygoteSpace::SweepCallback(size_t num_ptrs, mirror::Object** ptrs, void* arg) {
105   SweepCallbackContext* context = static_cast<SweepCallbackContext*>(arg);
106   DCHECK(context->space->IsZygoteSpace());
107   ZygoteSpace* zygote_space = context->space->AsZygoteSpace();
108   Locks::heap_bitmap_lock_->AssertExclusiveHeld(context->self);
109   accounting::CardTable* card_table = Runtime::Current()->GetHeap()->GetCardTable();
110   // If the bitmaps aren't swapped we need to clear the bits since the GC isn't going to re-swap
111   // the bitmaps as an optimization.
112   if (!context->swap_bitmaps) {
113     accounting::ContinuousSpaceBitmap* bitmap = zygote_space->GetLiveBitmap();
114     for (size_t i = 0; i < num_ptrs; ++i) {
115       bitmap->Clear(ptrs[i]);
116     }
117   }
118   // We don't free any actual memory to avoid dirtying the shared zygote pages.
119   for (size_t i = 0; i < num_ptrs; ++i) {
120     // Need to mark the card since this will update the mod-union table next GC cycle.
121     card_table->MarkCard(ptrs[i]);
122   }
123   zygote_space->objects_allocated_.FetchAndSubSequentiallyConsistent(num_ptrs);
124 }
125 
126 }  // namespace space
127 }  // namespace gc
128 }  // namespace art
129