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
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
|
#pragma once
#include <util/generic/hash.h>
#include <util/system/spinlock.h>
#include <array>
namespace NPrivate {
template <typename T, typename THash>
concept CHashableBy = requires (const THash& hash, const T& t) {
hash(t);
};
}
template <typename K, typename V, size_t BucketCount = 64, typename L = TAdaptiveLock>
class TConcurrentHashMap {
public:
using TActualMap = THashMap<K, V>;
using TLock = L;
struct TBucket {
friend class TConcurrentHashMap;
private:
TActualMap Map;
mutable TLock Mutex;
public:
TLock& GetMutex() const {
return Mutex;
}
TActualMap& GetMap() {
return Map;
}
const TActualMap& GetMap() const {
return Map;
}
const V& GetUnsafe(const K& key) const {
typename TActualMap::const_iterator it = Map.find(key);
Y_ABORT_UNLESS(it != Map.end(), "not found by key");
return it->second;
}
V& GetUnsafe(const K& key) {
typename TActualMap::iterator it = Map.find(key);
Y_ABORT_UNLESS(it != Map.end(), "not found by key");
return it->second;
}
V RemoveUnsafe(const K& key) {
typename TActualMap::iterator it = Map.find(key);
Y_ABORT_UNLESS(it != Map.end(), "removing non-existent key");
V r = std::move(it->second);
Map.erase(it);
return r;
}
bool HasUnsafe(const K& key) const {
typename TActualMap::const_iterator it = Map.find(key);
return (it != Map.end());
}
const V* TryGetUnsafe(const K& key) const {
typename TActualMap::const_iterator it = Map.find(key);
return it == Map.end() ? nullptr : &it->second;
}
V* TryGetUnsafe(const K& key) {
typename TActualMap::iterator it = Map.find(key);
return it == Map.end() ? nullptr : &it->second;
}
};
std::array<TBucket, BucketCount> Buckets;
public:
template <NPrivate::CHashableBy<THash<K>> TKey>
TBucket& GetBucketForKey(const TKey& key) {
return Buckets[THash<K>()(key) % BucketCount];
}
template <NPrivate::CHashableBy<THash<K>> TKey>
const TBucket& GetBucketForKey(const TKey& key) const {
return Buckets[THash<K>()(key) % BucketCount];
}
void Insert(const K& key, const V& value) {
TBucket& bucket = GetBucketForKey(key);
TGuard<TLock> guard(bucket.Mutex);
bucket.Map[key] = value;
}
void InsertUnique(const K& key, const V& value) {
TBucket& bucket = GetBucketForKey(key);
TGuard<TLock> guard(bucket.Mutex);
if (!bucket.Map.insert(std::make_pair(key, value)).second) {
Y_ABORT("non-unique key");
}
}
V& InsertIfAbsent(const K& key, const V& value) {
TBucket& bucket = GetBucketForKey(key);
TGuard<TLock> guard(bucket.Mutex);
return bucket.Map.insert(std::make_pair(key, value)).first->second;
}
template <typename TKey, typename... Args>
V& EmplaceIfAbsent(TKey&& key, Args&&... args) {
TBucket& bucket = GetBucketForKey(key);
TGuard<TLock> guard(bucket.Mutex);
if (V* value = bucket.TryGetUnsafe(key)) {
return *value;
}
return bucket.Map.emplace(
std::piecewise_construct,
std::forward_as_tuple(std::forward<TKey>(key)),
std::forward_as_tuple(std::forward<Args>(args)...)
).first->second;
}
template <typename Callable>
V& InsertIfAbsentWithInit(const K& key, Callable initFunc) {
TBucket& bucket = GetBucketForKey(key);
TGuard<TLock> guard(bucket.Mutex);
if (V* value = bucket.TryGetUnsafe(key)) {
return *value;
}
return bucket.Map.insert(std::make_pair(key, initFunc())).first->second;
}
V Get(const K& key) const {
const TBucket& bucket = GetBucketForKey(key);
TGuard<TLock> guard(bucket.Mutex);
return bucket.GetUnsafe(key);
}
bool Get(const K& key, V& result) const {
const TBucket& bucket = GetBucketForKey(key);
TGuard<TLock> guard(bucket.Mutex);
if (const V* value = bucket.TryGetUnsafe(key)) {
result = *value;
return true;
}
return false;
}
V Remove(const K& key) {
TBucket& bucket = GetBucketForKey(key);
TGuard<TLock> guard(bucket.Mutex);
return bucket.RemoveUnsafe(key);
}
bool Has(const K& key) const {
const TBucket& bucket = GetBucketForKey(key);
TGuard<TLock> guard(bucket.Mutex);
return bucket.HasUnsafe(key);
}
};
|
