[PATCH] mm/hugetlb: use some helper functions to cleanup code

[Miaohe Lin <linmiaohe@huawei.com>]

We could use pages_per_huge_page to get the number of pages per hugepage,
use get_hstate_idx to calculate hstate index, and use hstate_is_gigantic
to check if a hstate is gigantic to make code more succinct.

Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
---
 fs/hugetlbfs/inode.c | 2 +-
 mm/hugetlb.c         | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 701c82c36138..c262566f7c5d 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -1435,7 +1435,7 @@ static int get_hstate_idx(int page_size_log)
 
 	if (!h)
 		return -1;
-	return h - hstates;
+	return hstate_index(h);
 }
 
 /*
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 8f6c98096476..da347047ea10 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1271,7 +1271,7 @@ static void free_gigantic_page(struct page *page, unsigned int order)
 static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
 		int nid, nodemask_t *nodemask)
 {
-	unsigned long nr_pages = 1UL << huge_page_order(h);
+	unsigned long nr_pages = pages_per_huge_page(h);
 	if (nid == NUMA_NO_NODE)
 		nid = numa_mem_id();
 
@@ -3262,10 +3262,10 @@ static int __init hugepages_setup(char *s)
 
 	/*
 	 * Global state is always initialized later in hugetlb_init.
-	 * But we need to allocate >= MAX_ORDER hstates here early to still
+	 * But we need to allocate gigantic hstates here early to still
 	 * use the bootmem allocator.
 	 */
-	if (hugetlb_max_hstate && parsed_hstate->order >= MAX_ORDER)
+	if (hugetlb_max_hstate && hstate_is_gigantic(parsed_hstate))
 		hugetlb_hstate_alloc_pages(parsed_hstate);
 
 	last_mhp = mhp;
-- 
2.19.1