mm: convert lru_add_page_tail() to lru_add_split_folio()

Remove three hidden calls to compound_head() and accesses to page->lru.

Link: https://lkml.kernel.org/r/20250313151458.4145978-1-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index e3ed8e9523f5821210fc26f3c875f4d89ebd9125..10a86b681cf1e982797c9f2c89655aae19f267ba 100644 (file)
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -3262,25 +3262,25 @@ static void remap_page(struct folio *folio, unsigned long nr, int flags)
        }
 }
 
-static void lru_add_page_tail(struct folio *folio, struct page *tail,
+static void lru_add_split_folio(struct folio *folio, struct folio *new_folio,
                struct lruvec *lruvec, struct list_head *list)
 {
-       VM_BUG_ON_FOLIO(PageLRU(tail), folio);
+       VM_BUG_ON_FOLIO(folio_test_lru(new_folio), folio);
        lockdep_assert_held(&lruvec->lru_lock);
 
        if (list) {
                /* page reclaim is reclaiming a huge page */
                VM_WARN_ON(folio_test_lru(folio));
-               get_page(tail);
-               list_add_tail(&tail->lru, list);
+               folio_get(new_folio);
+               list_add_tail(&new_folio->lru, list);
        } else {
                /* head is still on lru (and we have it frozen) */
                VM_WARN_ON(!folio_test_lru(folio));
                if (folio_test_unevictable(folio))
-                       tail->mlock_count = 0;
+                       new_folio->mlock_count = 0;
                else
-                       list_add_tail(&tail->lru, &folio->lru);
-               SetPageLRU(tail);
+                       list_add_tail(&new_folio->lru, &folio->lru);
+               folio_set_lru(new_folio);
        }
 }
 
@@ -3581,8 +3581,8 @@ after_split:
                                        ((mapping || swap_cache) ?
                                                folio_nr_pages(release) : 0));
 
-                       lru_add_page_tail(origin_folio, &release->page,
-                                               lruvec, list);
+                       lru_add_split_folio(origin_folio, release, lruvec,
+                                       list);
 
                        /* Some pages can be beyond EOF: drop them from cache */
                        if (release->index >= end) {