On Mon, 26 Mar 2018, Wei Yang wrote:
> In 'commit c4e1be9ec113 ("mm, sparsemem: break out of loops early")',
> __highest_present_section_nr is introduced to reduce the loop counts for
> present section. This is also helpful for usemap and memmap allocation.
>
> This patch uses __highest_present_section_nr + 1 to optimize the loop.
>
> Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxx>
> ---
> mm/sparse.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/sparse.c b/mm/sparse.c
> index 7af5e7a92528..505050346249 100644
> --- a/mm/sparse.c
> +++ b/mm/sparse.c
> @@ -561,7 +561,7 @@ static void __init alloc_usemap_and_memmap(void (*alloc_func)
> map_count = 1;
> }
> /* ok, last chunk */
> - alloc_func(data, pnum_begin, NR_MEM_SECTIONS,
> + alloc_func(data, pnum_begin, __highest_present_section_nr+1,
> map_count, nodeid_begin);
> }
>
What happens if s/NR_MEM_SECTIONS/pnum/?
