Проблема с исходным кодом Голанга

Question

Когда структура mcentral вызывает cachespan, она сначала получает mspan из списка nonempty, а затем получает empty. Можно ли присвоить mspan с incache из 1?

type mcentral struct {
    lock      mutex
    spanclass spanClass
    nonempty  mSpanList // list of spans with a free object, ie a nonempty free list
    empty     mSpanList // list of spans with no free objects (or cached in an mcache)

    // nmalloc is the cumulative count of objects allocated from
    // this mcentral, assuming all spans in mcaches are
    // fully-allocated. Written atomically, read under STW.
    nmalloc uint64
}

func (c *mcentral) cacheSpan() *mspan {
   ... ... 
    for s = c.empty.first; s != nil; s = s.next {
        if s.sweepgen == sg-2 && atomic.Cas(&s.sweepgen, sg-2, sg-1) {
            // we have an empty span that requires sweeping,
            // sweep it and see if we can free some space in it
            c.empty.remove(s)
            // swept spans are at the end of the list
            c.empty.insertBack(s)
            unlock(&c.lock)
            s.sweep(true)
            freeIndex := s.nextFreeIndex()
            if freeIndex != s.nelems {
                s.freeindex = freeIndex
                goto havespan
            }
  ... ...