1//===-- sanitizer_allocator_stats.h -----------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// Part of the Sanitizer Allocator.
10//
11//===----------------------------------------------------------------------===//
12#ifndef SANITIZER_ALLOCATOR_H
13#error This file must be included inside sanitizer_allocator.h
14#endif
15
16// Memory allocator statistics
17enum AllocatorStat {
18  AllocatorStatAllocated,
19  AllocatorStatMapped,
20  AllocatorStatCount
21};
22
23typedef uptr AllocatorStatCounters[AllocatorStatCount];
24
25// Per-thread stats, live in per-thread cache.
26class AllocatorStats {
27 public:
28  void Init() {
29    internal_memset(this, 0, sizeof(*this));
30  }
31  void InitLinkerInitialized() {}
32
33  void Add(AllocatorStat i, uptr v) {
34    v += atomic_load(&stats_[i], memory_order_relaxed);
35    atomic_store(&stats_[i], v, memory_order_relaxed);
36  }
37
38  void Sub(AllocatorStat i, uptr v) {
39    v = atomic_load(&stats_[i], memory_order_relaxed) - v;
40    atomic_store(&stats_[i], v, memory_order_relaxed);
41  }
42
43  void Set(AllocatorStat i, uptr v) {
44    atomic_store(&stats_[i], v, memory_order_relaxed);
45  }
46
47  uptr Get(AllocatorStat i) const {
48    return atomic_load(&stats_[i], memory_order_relaxed);
49  }
50
51 private:
52  friend class AllocatorGlobalStats;
53  AllocatorStats *next_;
54  AllocatorStats *prev_;
55  atomic_uintptr_t stats_[AllocatorStatCount];
56};
57
58// Global stats, used for aggregation and querying.
59class AllocatorGlobalStats : public AllocatorStats {
60 public:
61  void InitLinkerInitialized() {
62    next_ = this;
63    prev_ = this;
64  }
65  void Init() {
66    internal_memset(this, 0, sizeof(*this));
67    InitLinkerInitialized();
68  }
69
70  void Register(AllocatorStats *s) {
71    SpinMutexLock l(&mu_);
72    s->next_ = next_;
73    s->prev_ = this;
74    next_->prev_ = s;
75    next_ = s;
76  }
77
78  void Unregister(AllocatorStats *s) {
79    SpinMutexLock l(&mu_);
80    s->prev_->next_ = s->next_;
81    s->next_->prev_ = s->prev_;
82    for (int i = 0; i < AllocatorStatCount; i++)
83      Add(AllocatorStat(i), s->Get(AllocatorStat(i)));
84  }
85
86  void Get(AllocatorStatCounters s) const {
87    internal_memset(s, 0, AllocatorStatCount * sizeof(uptr));
88    SpinMutexLock l(&mu_);
89    const AllocatorStats *stats = this;
90    for (;;) {
91      for (int i = 0; i < AllocatorStatCount; i++)
92        s[i] += stats->Get(AllocatorStat(i));
93      stats = stats->next_;
94      if (stats == this)
95        break;
96    }
97    // All stats must be non-negative.
98    for (int i = 0; i < AllocatorStatCount; i++)
99      s[i] = ((sptr)s[i]) >= 0 ? s[i] : 0;
100  }
101
102 private:
103  mutable StaticSpinMutex mu_;
104};
105
106
107