1 /*
2  * Copyright (C) 2013 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 #ifndef ART_RUNTIME_GC_SPACE_BUMP_POINTER_SPACE_INL_H_
18 #define ART_RUNTIME_GC_SPACE_BUMP_POINTER_SPACE_INL_H_
19 
20 #include "bump_pointer_space.h"
21 
22 #include "base/bit_utils.h"
23 
24 namespace art {
25 namespace gc {
26 namespace space {
27 
Alloc(Thread *,size_t num_bytes,size_t * bytes_allocated,size_t * usable_size,size_t * bytes_tl_bulk_allocated)28 inline mirror::Object* BumpPointerSpace::Alloc(Thread*, size_t num_bytes, size_t* bytes_allocated,
29                                                size_t* usable_size,
30                                                size_t* bytes_tl_bulk_allocated) {
31   num_bytes = RoundUp(num_bytes, kAlignment);
32   mirror::Object* ret = AllocNonvirtual(num_bytes);
33   if (LIKELY(ret != nullptr)) {
34     *bytes_allocated = num_bytes;
35     if (usable_size != nullptr) {
36       *usable_size = num_bytes;
37     }
38     *bytes_tl_bulk_allocated = num_bytes;
39   }
40   return ret;
41 }
42 
AllocThreadUnsafe(Thread * self,size_t num_bytes,size_t * bytes_allocated,size_t * usable_size,size_t * bytes_tl_bulk_allocated)43 inline mirror::Object* BumpPointerSpace::AllocThreadUnsafe(Thread* self, size_t num_bytes,
44                                                            size_t* bytes_allocated,
45                                                            size_t* usable_size,
46                                                            size_t* bytes_tl_bulk_allocated) {
47   Locks::mutator_lock_->AssertExclusiveHeld(self);
48   num_bytes = RoundUp(num_bytes, kAlignment);
49   uint8_t* end = end_.load(std::memory_order_relaxed);
50   if (end + num_bytes > growth_end_) {
51     return nullptr;
52   }
53   mirror::Object* obj = reinterpret_cast<mirror::Object*>(end);
54   end_.store(end + num_bytes, std::memory_order_relaxed);
55   *bytes_allocated = num_bytes;
56   // Use the CAS free versions as an optimization.
57   objects_allocated_.store(objects_allocated_.load(std::memory_order_relaxed) + 1,
58                            std::memory_order_relaxed);
59   bytes_allocated_.store(bytes_allocated_.load(std::memory_order_relaxed) + num_bytes,
60                          std::memory_order_relaxed);
61   if (UNLIKELY(usable_size != nullptr)) {
62     *usable_size = num_bytes;
63   }
64   *bytes_tl_bulk_allocated = num_bytes;
65   return obj;
66 }
67 
AllocNonvirtualWithoutAccounting(size_t num_bytes)68 inline mirror::Object* BumpPointerSpace::AllocNonvirtualWithoutAccounting(size_t num_bytes) {
69   DCHECK_ALIGNED(num_bytes, kAlignment);
70   uint8_t* old_end;
71   uint8_t* new_end;
72   do {
73     old_end = end_.load(std::memory_order_relaxed);
74     new_end = old_end + num_bytes;
75     // If there is no more room in the region, we are out of memory.
76     if (UNLIKELY(new_end > growth_end_)) {
77       return nullptr;
78     }
79   } while (!end_.CompareAndSetWeakSequentiallyConsistent(old_end, new_end));
80   return reinterpret_cast<mirror::Object*>(old_end);
81 }
82 
AllocNonvirtual(size_t num_bytes)83 inline mirror::Object* BumpPointerSpace::AllocNonvirtual(size_t num_bytes) {
84   mirror::Object* ret = AllocNonvirtualWithoutAccounting(num_bytes);
85   if (ret != nullptr) {
86     objects_allocated_.fetch_add(1, std::memory_order_relaxed);
87     bytes_allocated_.fetch_add(num_bytes, std::memory_order_relaxed);
88   }
89   return ret;
90 }
91 
92 }  // namespace space
93 }  // namespace gc
94 }  // namespace art
95 
96 #endif  // ART_RUNTIME_GC_SPACE_BUMP_POINTER_SPACE_INL_H_
97