Example continued

The code to add an element to the list is:

static inline void __list_add(struct list_head *new,
                              struct list_head *prev,
                              struct list_head *next)
{
    next->prev = new;
    new->next = next;
    new->prev = prev;
    prev->next = new;
}

It yields results like:






What if two processors add an element simultaneously?