1 files changed, 9 insertions, 42 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index e3c7ca7dc174..605f671203ef 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1343,46 +1343,6 @@ void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page)
 #endif
 
 /**
- * mem_cgroup_page_lruvec - return lruvec for isolating/putting an LRU page
- * @page: the page
- * @pgdat: pgdat of the page
- *
- * This function relies on page's memcg being stable - see the
- * access rules in commit_charge().
- */
-struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct pglist_data *pgdat)
-{
-	struct mem_cgroup_per_node *mz;
-	struct mem_cgroup *memcg;
-	struct lruvec *lruvec;
-
-	if (mem_cgroup_disabled()) {
-		lruvec = &pgdat->__lruvec;
-		goto out;
-	}
-
-	memcg = page_memcg(page);
-	/*
-	 * Swapcache readahead pages are added to the LRU - and
-	 * possibly migrated - before they are charged.
-	 */
-	if (!memcg)
-		memcg = root_mem_cgroup;
-
-	mz = mem_cgroup_page_nodeinfo(memcg, page);
-	lruvec = &mz->lruvec;
-out:
-	/*
-	 * Since a node can be onlined after the mem_cgroup was created,
-	 * we have to be prepared to initialize lruvec->zone here;
-	 * and if offlined then reonlined, we need to reinitialize it.
-	 */
-	if (unlikely(lruvec->pgdat != pgdat))
-		lruvec->pgdat = pgdat;
-	return lruvec;
-}
-
-/**
  * lock_page_lruvec - lock and return lruvec for a given page.
  * @page: the page
  *
@@ -6987,6 +6947,7 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage)
 		return;
 
 	memcg = page_memcg(oldpage);
+	VM_WARN_ON_ONCE_PAGE(!memcg, oldpage);
 	if (!memcg)
 		return;
 
@@ -7178,12 +7139,15 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
 	VM_BUG_ON_PAGE(PageLRU(page), page);
 	VM_BUG_ON_PAGE(page_count(page), page);
 
+	if (mem_cgroup_disabled())
+		return;
+
 	if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
 		return;
 
 	memcg = page_memcg(page);
 
-	/* Readahead page, never charged */
+	VM_WARN_ON_ONCE_PAGE(!memcg, page);
 	if (!memcg)
 		return;
 
@@ -7242,12 +7206,15 @@ int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry)
 	struct mem_cgroup *memcg;
 	unsigned short oldid;
 
+	if (mem_cgroup_disabled())
+		return 0;
+
 	if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
 		return 0;
 
 	memcg = page_memcg(page);
 
-	/* Readahead page, never charged */
+	VM_WARN_ON_ONCE_PAGE(!memcg, page);
 	if (!memcg)
 		return 0;