Re: [PATCH 1/6] Generic radix trees

[Kent Overstreet]

On Sat, May 26, 2018 at 11:16:42AM +0800, Liu Bo wrote:
> > +/*
> > + * Returns pointer to the specified byte @offset within @radix, allocating it if
> > + * necessary - newly allocated slots are always zeroed out:
> > + */
> > +void *__genradix_ptr_alloc(struct __genradix *radix, size_t offset,
> > +                          gfp_t gfp_mask)
> > +{
> > +       struct genradix_node **n;
> 
> Any reason that " struct genradix_node ** " is used here instead of "
> struct genradix_node * "?
> 
> Looks like this function only manipulates *n, am I missing something?

It stores to *n, when it has to allocate a node (including the root)