mm/hugetlb: create hstate_is_gigantic_no_runtime helper

This is a common condition used to skip operations that cannot be
performed on gigantic pages when runtime support is disabled.  This helper
is introduced as the condition will exist even more when allowing
"overcommit" of gigantic hugepages.  No functional change intended with
this patch.

Link: https://lkml.kernel.org/r/20251009172433.4158118-1-usamaarif642@gmail.com
Signed-off-by: Usama Arif <usamaarif642@gmail.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Oscar Salvador <osalvador@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Rik van Riel <riel@surriel.com>
Cc: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index e44f1301ae84b45f0325b32dd4a1186b09f15490..614352aa04d67f023a8faa1c3bf7025bffb77b72 100644 (file)
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -134,6 +134,17 @@ static void hugetlb_free_folio(struct folio *folio)
        folio_put(folio);
 }
 
+/*
+ * Check if the hstate represents gigantic pages but gigantic page
+ * runtime support is not available. This is a common condition used to
+ * skip operations that cannot be performed on gigantic pages when runtime
+ * support is disabled.
+ */
+static inline bool hstate_is_gigantic_no_runtime(struct hstate *h)
+{
+       return hstate_is_gigantic(h) && !gigantic_page_runtime_supported();
+}
+
 static inline bool subpool_is_free(struct hugepage_subpool *spool)
 {
        if (spool->count)
@@ -1555,7 +1566,7 @@ static void remove_hugetlb_folio(struct hstate *h, struct folio *folio,
        VM_BUG_ON_FOLIO(hugetlb_cgroup_from_folio_rsvd(folio), folio);
 
        lockdep_assert_held(&hugetlb_lock);
-       if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
+       if (hstate_is_gigantic_no_runtime(h))
                return;
 
        list_del(&folio->lru);
@@ -1617,7 +1628,7 @@ static void __update_and_free_hugetlb_folio(struct hstate *h,
 {
        bool clear_flag = folio_test_hugetlb_vmemmap_optimized(folio);
 
-       if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
+       if (hstate_is_gigantic_no_runtime(h))
                return;
 
        /*
@@ -2511,7 +2522,7 @@ static void return_unused_surplus_pages(struct hstate *h,
        /* Uncommit the reservation */
        h->resv_huge_pages -= unused_resv_pages;
 
-       if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
+       if (hstate_is_gigantic_no_runtime(h))
                goto out;
 
        /*
@@ -3725,7 +3736,7 @@ static void __init hugetlb_init_hstates(void)
                 * - If CMA allocation is possible, we can not demote
                 *   HUGETLB_PAGE_ORDER or smaller size pages.
                 */
-               if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
+               if (hstate_is_gigantic_no_runtime(h))
                        continue;
                if (hugetlb_cma_total_size() && h->order <= HUGETLB_PAGE_ORDER)
                        continue;
@@ -4202,7 +4213,7 @@ static ssize_t __nr_hugepages_store_common(bool obey_mempolicy,
        int err;
        nodemask_t nodes_allowed, *n_mask;
 
-       if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
+       if (hstate_is_gigantic_no_runtime(h))
                return -EINVAL;
 
        if (nid == NUMA_NO_NODE) {