Function ExtractStats

libs/tcmalloc-1.4/src/tcmalloc.cc:315–341

Get stats into "r". Also get per-size-class counts if class_count != NULL

// Get stats into "r".  Also get per-size-class counts if class_count != NULL
static void ExtractStats(TCMallocStats* r, uint64_t* class_count) {
  r->central_bytes = 0;
  r->transfer_bytes = 0;
  for (unsigned int cl = 0; cl < kNumClasses; ++cl) {
    const int length = Static::central_cache()[cl].length();
    const int tc_length = Static::central_cache()[cl].tc_length();
    const size_t size = static_cast<uint64_t>(
        Static::sizemap()->ByteSizeForClass(cl));
    r->central_bytes += (size * length);
    r->transfer_bytes += (size * tc_length);
    if (class_count) class_count[cl] = length + tc_length;
  }

  // Add stats from per-thread heaps
  r->thread_bytes = 0;
  { // scope
    SpinLockHolder h(Static::pageheap_lock());
    ThreadCache::GetThreadStats(&r->thread_bytes, class_count);
  }

  { //scope
    SpinLockHolder h(Static::pageheap_lock());
    r->system_bytes = Static::pageheap()->SystemBytes();
    r->metadata_bytes = tcmalloc::metadata_system_bytes();
    r->pageheap_bytes = Static::pageheap()->FreeBytes();
  }
}

// WRITE stats to "out"
static void DumpStats(TCMalloc_Printer* out, int level) {