delay without delay()

const int INTERVAL = 10;
uint64_t _previous_msTimeNow=0;

void loop_A()
{
    uint64_t msTimeNow = std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock::now().time_since_epoch()).count();
    if(msTimeNow % INTERVAL == 0)
    {
        doSomething();
    }

}

void loop_B()
{
    uint64_t msTimeNow = std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock::now().time_since_epoch()).count();
    if(msTimeNow - _previous_msTimeNow >= INTERVAL)
    {
        _previous_msTimeNow = msTimeNow;
        doSomething();
    }
}