On Mon, Mar 26, 2018 at 03:47:03PM -0700, David Rientjes wrote:
>On Tue, 27 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/?
>>
>> I have tried this :-)
>>
>> The last pnum is -1 from next_present_section_nr().
>>
>
>Lol. I think it would make more sense for the second patch to come before
>the first, but feel free to add
>
Thanks for your comment.
Do I need to reorder the patch and send v2?
>Acked-by: David Rientjes <rientjes@xxxxxxxxxx>
--
Wei Yang
Help you, Help me
