hugetlb_cgroup: use helper for_each_hstate and hstate_index

Use helper for_each_hstate and hstate_index to iterate the hstate and get
the hstate index. Minor readability improvement.

Link: https://lkml.kernel.org/r/20220729080106.12752-6-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/hugetlb_cgroup.c b/mm/hugetlb_cgroup.c
index 2affccfe59f1abf21f3d3d0e7117f4783ae27950..f61d132df52b34e304553ee899052c07a3929ac3 100644 (file)
--- a/mm/hugetlb_cgroup.c
+++ b/mm/hugetlb_cgroup.c
@@ -75,11 +75,11 @@ parent_hugetlb_cgroup(struct hugetlb_cgroup *h_cg)
 
 static inline bool hugetlb_cgroup_have_usage(struct hugetlb_cgroup *h_cg)
 {
-       int idx;
+       struct hstate *h;
 
-       for (idx = 0; idx < hugetlb_max_hstate; idx++) {
+       for_each_hstate(h) {
                if (page_counter_read(
-                               hugetlb_cgroup_counter_from_cgroup(h_cg, idx)))
+                   hugetlb_cgroup_counter_from_cgroup(h_cg, hstate_index(h))))
                        return true;
        }
        return false;
@@ -225,17 +225,14 @@ static void hugetlb_cgroup_css_offline(struct cgroup_subsys_state *css)
        struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(css);
        struct hstate *h;
        struct page *page;
-       int idx;
 
        do {
-               idx = 0;
                for_each_hstate(h) {
                        spin_lock_irq(&hugetlb_lock);
                        list_for_each_entry(page, &h->hugepage_activelist, lru)
-                               hugetlb_cgroup_move_parent(idx, h_cg, page);
+                               hugetlb_cgroup_move_parent(hstate_index(h), h_cg, page);
 
                        spin_unlock_irq(&hugetlb_lock);
-                       idx++;
                }
                cond_resched();
        } while (hugetlb_cgroup_have_usage(h_cg));