Matthew Wilcox wrote:
> __get_free_pages() calls alloc_pages, finds the page_address() and
> throws away the struct page *.  Slab then calls virt_to_page to get it
> back again.  Much more efficient for slab to call alloc_pages itself,
> as well as making the NUMA and non-NUMA cases more similarr to each other.

Here is a better patch:

Remove the special case of nodeid == -1.  Instead, use numa_node_id() 
when calling cache_grow().

Signed-off-by: Brian Gerst <bgerst@didntduck.org>