[PATCH] mm/sparse: use __nr_to_section(section_nr) to get mem_section

[Wei Yang]

__pfn_to_section is defined as __nr_to_section(pfn_to_section_nr(pfn)).

Since we already get section_nr, it is not necessary to get mem_section
from start_pfn. By doing so, we reduce one redundant operation.

Signed-off-by: Wei Yang <richardw.y...@linux.intel.com>
---
 mm/sparse.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/sparse.c b/mm/sparse.c
index 72f010d9bff5..95158a148cd1 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -867,7 +867,7 @@ int __meminit sparse_add_section(int nid, unsigned long 
start_pfn,
         */
        page_init_poison(pfn_to_page(start_pfn), sizeof(struct page) * 
nr_pages);
 
-       ms = __pfn_to_section(start_pfn);
+       ms = __nr_to_section(section_nr);
        set_section_nid(section_nr, nid);
        section_mark_present(ms);
 
-- 
2.17.1