blob: 06552535405a4971361f5890e6445db1c891e2a8 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
|
// Copyright 2019 The TCMalloc Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef TCMALLOC_ARENA_H_
#define TCMALLOC_ARENA_H_
#include <stddef.h>
#include <stdint.h>
#include "absl/base/attributes.h"
#include "absl/base/thread_annotations.h"
#include "tcmalloc/common.h"
GOOGLE_MALLOC_SECTION_BEGIN
namespace tcmalloc {
namespace tcmalloc_internal {
// Arena allocation; designed for use by tcmalloc internal data structures like
// spans, profiles, etc. Always expands.
class Arena {
public:
constexpr Arena()
: free_area_(nullptr), free_avail_(0), bytes_allocated_(0) {}
// Return a properly aligned byte array of length "bytes". Crashes if
// allocation fails. Requires pageheap_lock is held.
ABSL_ATTRIBUTE_RETURNS_NONNULL void* Alloc(size_t bytes,
int alignment = kAlignment)
ABSL_EXCLUSIVE_LOCKS_REQUIRED(pageheap_lock);
// Returns the total number of bytes allocated from this arena. Requires
// pageheap_lock is held.
uint64_t bytes_allocated() const
ABSL_EXCLUSIVE_LOCKS_REQUIRED(pageheap_lock) {
return bytes_allocated_;
}
private:
// How much to allocate from system at a time
static constexpr int kAllocIncrement = 128 << 10;
// Free area from which to carve new objects
char* free_area_ ABSL_GUARDED_BY(pageheap_lock);
size_t free_avail_ ABSL_GUARDED_BY(pageheap_lock);
// Total number of bytes allocated from this arena
uint64_t bytes_allocated_ ABSL_GUARDED_BY(pageheap_lock);
Arena(const Arena&) = delete;
Arena& operator=(const Arena&) = delete;
};
} // namespace tcmalloc_internal
} // namespace tcmalloc
GOOGLE_MALLOC_SECTION_END
#endif // TCMALLOC_ARENA_H_
|
