libsanitizer/sanitizer_common/sanitizer_allocator_stats.h

   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
  17 enum AllocatorStat {
  18   AllocatorStatAllocated,
  19   AllocatorStatMapped,
  20   AllocatorStatCount
  21 };
  22
  23 typedef uptr AllocatorStatCounters[AllocatorStatCount];
  24
  25 // Per-thread stats, live in per-thread cache.
  26 class 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.
  59 class 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