1 files changed, 19 insertions, 110 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 7f1ca1065316..04973c084c63 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3398,7 +3398,7 @@ static void mem_cgroup_id_remove(struct mem_cgroup *memcg)
 	}
 }
 
-static void __maybe_unused mem_cgroup_id_get_many(struct mem_cgroup *memcg,
+void __maybe_unused mem_cgroup_id_get_many(struct mem_cgroup *memcg,
 					   unsigned int n)
 {
 	refcount_add(n, &memcg->id.ref);
@@ -3419,6 +3419,24 @@ static inline void mem_cgroup_id_put(struct mem_cgroup *memcg)
 	mem_cgroup_id_put_many(memcg, 1);
 }
 
+struct mem_cgroup *mem_cgroup_id_get_online(struct mem_cgroup *memcg)
+{
+	while (!refcount_inc_not_zero(&memcg->id.ref)) {
+		/*
+		 * The root cgroup cannot be destroyed, so it's refcount must
+		 * always be >= 1.
+		 */
+		if (WARN_ON_ONCE(mem_cgroup_is_root(memcg))) {
+			VM_BUG_ON(1);
+			break;
+		}
+		memcg = parent_mem_cgroup(memcg);
+		if (!memcg)
+			memcg = root_mem_cgroup;
+	}
+	return memcg;
+}
+
 /**
  * mem_cgroup_from_id - look up a memcg from a memcg id
  * @id: the memcg id to look up
@@ -4604,40 +4622,6 @@ int mem_cgroup_swapin_charge_folio(struct folio *folio, struct mm_struct *mm,
 	return ret;
 }
 
-/*
- * mem_cgroup_swapin_uncharge_swap - uncharge swap slot
- * @entry: the first swap entry for which the pages are charged
- * @nr_pages: number of pages which will be uncharged
- *
- * Call this function after successfully adding the charged page to swapcache.
- *
- * Note: This function assumes the page for which swap slot is being uncharged
- * is order 0 page.
- */
-void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry, unsigned int nr_pages)
-{
-	/*
-	 * Cgroup1's unified memory+swap counter has been charged with the
-	 * new swapcache page, finish the transfer by uncharging the swap
-	 * slot. The swap slot would also get uncharged when it dies, but
-	 * it can stick around indefinitely and we'd count the page twice
-	 * the entire time.
-	 *
-	 * Cgroup2 has separate resource counters for memory and swap,
-	 * so this is a non-issue here. Memory and swap charge lifetimes
-	 * correspond 1:1 to page and swap slot lifetimes: we charge the
-	 * page to memory here, and uncharge swap when the slot is freed.
-	 */
-	if (do_memsw_account()) {
-		/*
-		 * The swap entry might not get freed for a long time,
-		 * let's not wait for it.  The page already received a
-		 * memory+swap charge, drop the swap entry duplicate.
-		 */
-		mem_cgroup_uncharge_swap(entry, nr_pages);
-	}
-}
-
 struct uncharge_gather {
 	struct mem_cgroup *memcg;
 	unsigned long nr_memory;
@@ -4963,81 +4947,6 @@ static int __init mem_cgroup_init(void)
 subsys_initcall(mem_cgroup_init);
 
 #ifdef CONFIG_SWAP
-static struct mem_cgroup *mem_cgroup_id_get_online(struct mem_cgroup *memcg)
-{
-	while (!refcount_inc_not_zero(&memcg->id.ref)) {
-		/*
-		 * The root cgroup cannot be destroyed, so it's refcount must
-		 * always be >= 1.
-		 */
-		if (WARN_ON_ONCE(mem_cgroup_is_root(memcg))) {
-			VM_BUG_ON(1);
-			break;
-		}
-		memcg = parent_mem_cgroup(memcg);
-		if (!memcg)
-			memcg = root_mem_cgroup;
-	}
-	return memcg;
-}
-
-/**
- * mem_cgroup_swapout - transfer a memsw charge to swap
- * @folio: folio whose memsw charge to transfer
- * @entry: swap entry to move the charge to
- *
- * Transfer the memsw charge of @folio to @entry.
- */
-void mem_cgroup_swapout(struct folio *folio, swp_entry_t entry)
-{
-	struct mem_cgroup *memcg, *swap_memcg;
-	unsigned int nr_entries;
-
-	VM_BUG_ON_FOLIO(folio_test_lru(folio), folio);
-	VM_BUG_ON_FOLIO(folio_ref_count(folio), folio);
-
-	if (mem_cgroup_disabled())
-		return;
-
-	if (!do_memsw_account())
-		return;
-
-	memcg = folio_memcg(folio);
-
-	VM_WARN_ON_ONCE_FOLIO(!memcg, folio);
-	if (!memcg)
-		return;
-
-	/*
-	 * In case the memcg owning these pages has been offlined and doesn't
-	 * have an ID allocated to it anymore, charge the closest online
-	 * ancestor for the swap instead and transfer the memory+swap charge.
-	 */
-	swap_memcg = mem_cgroup_id_get_online(memcg);
-	nr_entries = folio_nr_pages(folio);
-	/* Get references for the tail pages, too */
-	if (nr_entries > 1)
-		mem_cgroup_id_get_many(swap_memcg, nr_entries - 1);
-	mod_memcg_state(swap_memcg, MEMCG_SWAP, nr_entries);
-
-	swap_cgroup_record(folio, mem_cgroup_id(swap_memcg), entry);
-
-	folio_unqueue_deferred_split(folio);
-	folio->memcg_data = 0;
-
-	if (!mem_cgroup_is_root(memcg))
-		page_counter_uncharge(&memcg->memory, nr_entries);
-
-	if (memcg != swap_memcg) {
-		if (!mem_cgroup_is_root(swap_memcg))
-			page_counter_charge(&swap_memcg->memsw, nr_entries);
-		page_counter_uncharge(&memcg->memsw, nr_entries);
-	}
-
-	memcg1_swapout(folio, memcg);
-	css_put(&memcg->css);
-}
-
 /**
  * __mem_cgroup_try_charge_swap - try charging swap space for a folio
  * @folio: folio being added to swap