reference, declarationdefinition
definition → references, declarations, derived classes, virtual overrides
reference to multiple definitions → definitions
unreferenced
    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
//===-- sanitizer_allocator_stats.h -----------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// Part of the Sanitizer Allocator.
//
//===----------------------------------------------------------------------===//
#ifndef SANITIZER_ALLOCATOR_H
#error This file must be included inside sanitizer_allocator.h
#endif

// Memory allocator statistics
enum AllocatorStat {
  AllocatorStatAllocated,
  AllocatorStatMapped,
  AllocatorStatCount
};

typedef uptr AllocatorStatCounters[AllocatorStatCount];

// Per-thread stats, live in per-thread cache.
class AllocatorStats {
 public:
  void Init() {
    internal_memset(this, 0, sizeof(*this));
  }
  void InitLinkerInitialized() {}

  void Add(AllocatorStat i, uptr v) {
    v += atomic_load(&stats_[i], memory_order_relaxed);
    atomic_store(&stats_[i], v, memory_order_relaxed);
  }

  void Sub(AllocatorStat i, uptr v) {
    v = atomic_load(&stats_[i], memory_order_relaxed) - v;
    atomic_store(&stats_[i], v, memory_order_relaxed);
  }

  void Set(AllocatorStat i, uptr v) {
    atomic_store(&stats_[i], v, memory_order_relaxed);
  }

  uptr Get(AllocatorStat i) const {
    return atomic_load(&stats_[i], memory_order_relaxed);
  }

 private:
  friend class AllocatorGlobalStats;
  AllocatorStats *next_;
  AllocatorStats *prev_;
  atomic_uintptr_t stats_[AllocatorStatCount];
};

// Global stats, used for aggregation and querying.
class AllocatorGlobalStats : public AllocatorStats {
 public:
  void InitLinkerInitialized() {
    next_ = this;
    prev_ = this;
  }
  void Init() {
    internal_memset(this, 0, sizeof(*this));
    InitLinkerInitialized();
  }

  void Register(AllocatorStats *s) {
    SpinMutexLock l(&mu_);
    s->next_ = next_;
    s->prev_ = this;
    next_->prev_ = s;
    next_ = s;
  }

  void Unregister(AllocatorStats *s) {
    SpinMutexLock l(&mu_);
    s->prev_->next_ = s->next_;
    s->next_->prev_ = s->prev_;
    for (int i = 0; i < AllocatorStatCount; i++)
      Add(AllocatorStat(i), s->Get(AllocatorStat(i)));
  }

  void Get(AllocatorStatCounters s) const {
    internal_memset(s, 0, AllocatorStatCount * sizeof(uptr));
    SpinMutexLock l(&mu_);
    const AllocatorStats *stats = this;
    for (;;) {
      for (int i = 0; i < AllocatorStatCount; i++)
        s[i] += stats->Get(AllocatorStat(i));
      stats = stats->next_;
      if (stats == this)
        break;
    }
    // All stats must be non-negative.
    for (int i = 0; i < AllocatorStatCount; i++)
      s[i] = ((sptr)s[i]) >= 0 ? s[i] : 0;
  }

 private:
  mutable StaticSpinMutex mu_;
};