Function mmapAlignedZeroedMemory

cachelib/common/Utils.cpp:168–183

}

void* mmapAlignedZeroedMemory(size_t alignment,
                              size_t numBytes,
                              bool noAccess) {
  // to enforce alignment, we try to make sure that the address we return is
  // aligned to slab size.
  size_t newBytes = numBytes + alignment;
  const auto protFlag = noAccess ? PROT_NONE : PROT_READ | PROT_WRITE;
  const auto mapFlag = MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE;
  void* memory = mmap(nullptr, newBytes, protFlag, mapFlag, -1, 0);
  if (memory != MAP_FAILED) {
    auto alignedMemory = align(alignment, numBytes, memory, newBytes);
    XDCHECK_NE(alignedMemory, nullptr);
    return alignedMemory;
  }
  throw std::system_error(errno, std::system_category(), "Cannot mmap");
}

void setMaxLockMemory(uint64_t bytes) {
  struct rlimit rlim{bytes, bytes};