[Patch v2 3/7] mm/hugetlb: use list_splice to merge two list at once

[Wei Yang]

Instead of add allocated file_region one by one to region_cache, we
could use list_splice to merge two list at once.

Also we know the number of entries in the list, increase the number
directly.

Signed-off-by: Wei Yang <richard.weiy...@linux.alibaba.com>
Reviewed-by: Baoquan He <b...@redhat.com>
Reviewed-by: Mike Kravetz <mike.krav...@oracle.com>
---
 mm/hugetlb.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index f325839be617..cbe67428bf99 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -441,11 +441,8 @@ static int allocate_file_region_entries(struct resv_map 
*resv,
 
                spin_lock(&resv->lock);
 
-               list_for_each_entry_safe(rg, trg, &allocated_regions, link) {
-                       list_del(&rg->link);
-                       list_add(&rg->link, &resv->region_cache);
-                       resv->region_cache_count++;
-               }
+               list_splice(&allocated_regions, &resv->region_cache);
+               resv->region_cache_count += to_allocate;
        }
 
        return 0;
-- 
2.20.1 (Apple Git-117)