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
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
|
#pragma clang system_header
// Copyright 2022 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_HINTED_TRACKER_LISTS_H_
#define TCMALLOC_HINTED_TRACKER_LISTS_H_
#include <cstddef>
#include "tcmalloc/internal/config.h"
#include "tcmalloc/internal/linked_list.h"
#include "tcmalloc/internal/logging.h"
#include "tcmalloc/internal/range_tracker.h"
GOOGLE_MALLOC_SECTION_BEGIN
namespace tcmalloc {
namespace tcmalloc_internal {
// This class wraps an array of N TrackerLists and a Bitmap storing which
// elements are non-empty.
template <class TrackerType, size_t N>
class HintedTrackerLists {
public:
using TrackerList = TList<TrackerType>;
constexpr HintedTrackerLists() : size_{} {}
// Removes a TrackerType from the first non-empty freelist with index at
// least n and returns it. Returns nullptr if there is none.
TrackerType* GetLeast(const size_t n) {
TC_ASSERT_LT(n, N);
size_t i = nonempty_.FindSet(n);
if (i == N) {
return nullptr;
}
TC_ASSERT(!lists_[i].empty());
TrackerType* pt = lists_[i].first();
if (lists_[i].remove(pt)) {
nonempty_.ClearBit(i);
}
--size_;
return pt;
}
// Returns a pointer to the TrackerType from the first non-empty freelist with
// index at least n and returns it. Returns nullptr if there is none.
//
// Unlike GetLeast, this does not remove the pointer from the list when it is
// found.
TrackerType* PeekLeast(const size_t n) {
TC_ASSERT_LT(n, N);
size_t i = nonempty_.FindSet(n);
if (i == N) {
return nullptr;
}
TC_ASSERT(!lists_[i].empty());
return lists_[i].first();
}
// Adds pointer <pt> to the nonempty_[i] list.
// REQUIRES: i < N && pt != nullptr.
void Add(TrackerType* pt, const size_t i) {
TC_ASSERT_LT(i, N);
TC_ASSERT_NE(pt, nullptr);
lists_[i].prepend(pt);
++size_;
nonempty_.SetBit(i);
}
// Removes pointer <pt> from the nonempty_[i] list.
// REQUIRES: i < N && pt != nullptr.
void Remove(TrackerType* pt, const size_t i) {
TC_ASSERT_LT(i, N);
TC_ASSERT_NE(pt, nullptr);
if (lists_[i].remove(pt)) {
nonempty_.ClearBit(i);
}
--size_;
}
const TrackerList& operator[](const size_t n) const {
TC_ASSERT_LT(n, N);
return lists_[n];
}
size_t size() const { return size_; }
bool empty() const { return size_ == 0; }
// Returns length of the list at an index <n>.
// REQUIRES: n < N.
size_t SizeOfList(const size_t n) const {
TC_ASSERT_LT(n, N);
return lists_[n].length();
}
// Runs a functor on all pointers in the TrackerLists.
// This method is const but the Functor gets passed a non-const pointer.
// This quirk is inherited from TrackerList.
template <typename Functor>
void Iter(const Functor& func, size_t start) const {
size_t i = nonempty_.FindSet(start);
while (i < N) {
auto& list = lists_[i];
TC_ASSERT(!list.empty());
for (TrackerType* pt : list) {
func(*pt);
}
i++;
if (i < N) i = nonempty_.FindSet(i);
}
}
private:
TrackerList lists_[N];
size_t size_;
Bitmap<N> nonempty_;
};
} // namespace tcmalloc_internal
} // namespace tcmalloc
GOOGLE_MALLOC_SECTION_END
#endif // TCMALLOC_HINTED_TRACKER_LISTS_H_
|
