Merge tag 'mm-stable-2024-07-21-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - In the series "mm: Avoid possible overflows in dirty throttling" Jan
   Kara addresses a couple of issues in the writeback throttling code.
   These fixes are also targetted at -stable kernels.

 - Ryusuke Konishi's series "nilfs2: fix potential issues related to
   reserved inodes" does that. This should actually be in the
   mm-nonmm-stable tree, along with the many other nilfs2 patches. My
   bad.

 - More folio conversions from Kefeng Wang in the series "mm: convert to
   folio_alloc_mpol()"

 - Kemeng Shi has sent some cleanups to the writeback code in the series
   "Add helper functions to remove repeated code and improve readability
   of cgroup writeback"

 - Kairui Song has made the swap code a little smaller and a little
   faster in the series "mm/swap: clean up and optimize swap cache
   index".

 - In the series "mm/memory: cleanly support zeropage in
   vm_insert_page*(), vm_map_pages*() and vmf_insert_mixed()" David
   Hildenbrand has reworked the rather sketchy handling of the use of
   the zeropage in MAP_SHARED mappings. I don't see any runtime effects
   here - more a cleanup/understandability/maintainablity thing.

 - Dev Jain has improved selftests/mm/va_high_addr_switch.c's handling
   of higher addresses, for aarch64. The (poorly named) series is
   "Restructure va_high_addr_switch".

 - The core TLB handling code gets some cleanups and possible slight
   optimizations in Bang Li's series "Add update_mmu_tlb_range() to
   simplify code".

 - Jane Chu has improved the handling of our
   fake-an-unrecoverable-memory-error testing feature MADV_HWPOISON in
   the series "Enhance soft hwpoison handling and injection".

 - Jeff Johnson has sent a billion patches everywhere to add
   MODULE_DESCRIPTION() to everything. Some landed in this pull.

 - In the series "mm: cleanup MIGRATE_SYNC_NO_COPY mode", Kefeng Wang
   has simplified migration's use of hardware-offload memory copying.

 - Yosry Ahmed performs more folio API conversions in his series "mm:
   zswap: trivial folio conversions".

 - In the series "large folios swap-in: handle refault cases first",
   Chuanhua Han inches us forward in the handling of large pages in the
   swap code. This is a cleanup and optimization, working toward the end
   objective of full support of large folio swapin/out.

 - In the series "mm,swap: cleanup VMA based swap readahead window
   calculation", Huang Ying has contributed some cleanups and a possible
   fixlet to his VMA based swap readahead code.

 - In the series "add mTHP support for anonymous shmem" Baolin Wang has
   taught anonymous shmem mappings to use multisize THP. By default this
   is a no-op - users must opt in vis sysfs controls. Dramatic
   improvements in pagefault latency are realized.

 - David Hildenbrand has some cleanups to our remaining use of
   page_mapcount() in the series "fs/proc: move page_mapcount() to
   fs/proc/internal.h".

 - David also has some highmem accounting cleanups in the series
   "mm/highmem: don't track highmem pages manually".

 - Build-time fixes and cleanups from John Hubbard in the series
   "cleanups, fixes, and progress towards avoiding "make headers"".

 - Cleanups and consolidation of the core pagemap handling from Barry
   Song in the series "mm: introduce pmd|pte_needs_soft_dirty_wp helpers
   and utilize them".

 - Lance Yang's series "Reclaim lazyfree THP without splitting" has
   reduced the latency of the reclaim of pmd-mapped THPs under fairly
   common circumstances. A 10x speedup is seen in a microbenchmark.

   It does this by punting to aother CPU but I guess that's a win unless
   all CPUs are pegged.

 - hugetlb_cgroup cleanups from Xiu Jianfeng in the series
   "mm/hugetlb_cgroup: rework on cftypes".

 - Miaohe Lin's series "Some cleanups for memory-failure" does just that
   thing.

 - Someone other than SeongJae has developed a DAMON feature in Honggyu
   Kim's series "DAMON based tiered memory management for CXL memory".
   This adds DAMON features which may be used to help determine the
   efficiency of our placement of CXL/PCIe attached DRAM.

 - DAMON user API centralization and simplificatio work in SeongJae
   Park's series "mm/damon: introduce DAMON parameters online commit
   function".

 - In the series "mm: page_type, zsmalloc and page_mapcount_reset()"
   David Hildenbrand does some maintenance work on zsmalloc - partially
   modernizing its use of pageframe fields.

 - Kefeng Wang provides more folio conversions in the series "mm: remove
   page_maybe_dma_pinned() and page_mkclean()".

 - More cleanup from David Hildenbrand, this time in the series
   "mm/memory_hotplug: use PageOffline() instead of PageReserved() for
   !ZONE_DEVICE". It "enlightens memory hotplug more about PageOffline()
   pages" and permits the removal of some virtio-mem hacks.

 - Barry Song's series "mm: clarify folio_add_new_anon_rmap() and
   __folio_add_anon_rmap()" is a cleanup to the anon folio handling in
   preparation for mTHP (multisize THP) swapin.

 - Kefeng Wang's series "mm: improve clear and copy user folio"
   implements more folio conversions, this time in the area of large
   folio userspace copying.

 - The series "Docs/mm/damon/maintaier-profile: document a mailing tool
   and community meetup series" tells people how to get better involved
   with other DAMON developers. From SeongJae Park.

 - A large series ("kmsan: Enable on s390") from Ilya Leoshkevich does
   that.

 - David Hildenbrand sends along more cleanups, this time against the
   migration code. The series is "mm/migrate: move NUMA hinting fault
   folio isolation + checks under PTL".

 - Jan Kara has found quite a lot of strangenesses and minor errors in
   the readahead code. He addresses this in the series "mm: Fix various
   readahead quirks".

 - SeongJae Park's series "selftests/damon: test DAMOS tried regions and
   {min,max}_nr_regions" adds features and addresses errors in DAMON's
   self testing code.

 - Gavin Shan has found a userspace-triggerable WARN in the pagecache
   code. The series "mm/filemap: Limit page cache size to that supported
   by xarray" addresses this. The series is marked cc:stable.

 - Chengming Zhou's series "mm/ksm: cmp_and_merge_page() optimizations
   and cleanup" cleans up and slightly optimizes KSM.

 - Roman Gushchin has separated the memcg-v1 and memcg-v2 code - lots of
   code motion. The series (which also makes the memcg-v1 code
   Kconfigurable) are "mm: memcg: separate legacy cgroup v1 code and put
   under config option" and "mm: memcg: put cgroup v1-specific memcg
   data under CONFIG_MEMCG_V1"

 - Dan Schatzberg's series "Add swappiness argument to memory.reclaim"
   adds an additional feature to this cgroup-v2 control file.

 - The series "Userspace controls soft-offline pages" from Jiaqi Yan
   permits userspace to stop the kernel's automatic treatment of
   excessive correctable memory errors. In order to permit userspace to
   monitor and handle this situation.

 - Kefeng Wang's series "mm: migrate: support poison recover from
   migrate folio" teaches the kernel to appropriately handle migration
   from poisoned source folios rather than simply panicing.

 - SeongJae Park's series "Docs/damon: minor fixups and improvements"
   does those things.

 - In the series "mm/zsmalloc: change back to per-size_class lock"
   Chengming Zhou improves zsmalloc's scalability and memory
   utilization.

 - Vivek Kasireddy's series "mm/gup: Introduce memfd_pin_folios() for
   pinning memfd folios" makes the GUP code use FOLL_PIN rather than
   bare refcount increments. So these paes can first be moved aside if
   they reside in the movable zone or a CMA block.

 - Andrii Nakryiko has added a binary ioctl()-based API to
   /proc/pid/maps for much faster reading of vma information. The series
   is "query VMAs from /proc/<pid>/maps".

 - In the series "mm: introduce per-order mTHP split counters" Lance
   Yang improves the kernel's presentation of developer information
   related to multisize THP splitting.

 - Michael Ellerman has developed the series "Reimplement huge pages
   without hugepd on powerpc (8xx, e500, book3s/64)". This permits
   userspace to use all available huge page sizes.

 - In the series "revert unconditional slab and page allocator fault
   injection calls" Vlastimil Babka removes a performance-affecting and
   not very useful feature from slab fault injection.

* tag 'mm-stable-2024-07-21-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (411 commits)
  mm/mglru: fix ineffective protection calculation
  mm/zswap: fix a white space issue
  mm/hugetlb: fix kernel NULL pointer dereference when migrating hugetlb folio
  mm/hugetlb: fix possible recursive locking detected warning
  mm/gup: clear the LRU flag of a page before adding to LRU batch
  mm/numa_balancing: teach mpol_to_str about the balancing mode
  mm: memcg1: convert charge move flags to unsigned long long
  alloc_tag: fix page_ext_get/page_ext_put sequence during page splitting
  lib: reuse page_ext_data() to obtain codetag_ref
  lib: add missing newline character in the warning message
  mm/mglru: fix overshooting shrinker memory
  mm/mglru: fix div-by-zero in vmpressure_calc_level()
  mm/kmemleak: replace strncpy() with strscpy()
  mm, page_alloc: put should_fail_alloc_page() back behing CONFIG_FAIL_PAGE_ALLOC
  mm, slab: put should_failslab() back behind CONFIG_SHOULD_FAILSLAB
  mm: ignore data-race in __swap_writepage
  hugetlbfs: ensure generic_hugetlb_get_unmapped_area() returns higher address than mmap_min_addr
  mm: shmem: rename mTHP shmem counters
  mm: swap_state: use folio_alloc_mpol() in __read_swap_cache_async()
  mm/migrate: putback split folios when numa hint migration fails
  ...

1 files changed, 120 insertions, 3239 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 8f2f1bb18c9c..960371788687 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -28,7 +28,6 @@
 #include <linux/page_counter.h>
 #include <linux/memcontrol.h>
 #include <linux/cgroup.h>
-#include <linux/pagewalk.h>
 #include <linux/sched/mm.h>
 #include <linux/shmem_fs.h>
 #include <linux/hugetlb.h>
@@ -45,14 +44,11 @@
 #include <linux/mutex.h>
 #include <linux/rbtree.h>
 #include <linux/slab.h>
-#include <linux/swap.h>
 #include <linux/swapops.h>
 #include <linux/spinlock.h>
-#include <linux/eventfd.h>
-#include <linux/poll.h>
-#include <linux/sort.h>
 #include <linux/fs.h>
 #include <linux/seq_file.h>
+#include <linux/parser.h>
 #include <linux/vmpressure.h>
 #include <linux/memremap.h>
 #include <linux/mm_inline.h>
@@ -60,7 +56,6 @@
 #include <linux/cpu.h>
 #include <linux/oom.h>
 #include <linux/lockdep.h>
-#include <linux/file.h>
 #include <linux/resume_user_mode.h>
 #include <linux/psi.h>
 #include <linux/seq_buf.h>
@@ -70,7 +65,7 @@
 #include <net/sock.h>
 #include <net/ip.h>
 #include "slab.h"
-#include "swap.h"
+#include "memcontrol-v1.h"
 
 #include <linux/uaccess.h>
 
@@ -98,140 +93,9 @@ static bool cgroup_memory_nobpf __ro_after_init;
 static DECLARE_WAIT_QUEUE_HEAD(memcg_cgwb_frn_waitq);
 #endif
 
-/* Whether legacy memory+swap accounting is active */
-static bool do_memsw_account(void)
-{
-	return !cgroup_subsys_on_dfl(memory_cgrp_subsys);
-}
-
 #define THRESHOLDS_EVENTS_TARGET 128
 #define SOFTLIMIT_EVENTS_TARGET 1024
 
-/*
- * Cgroups above their limits are maintained in a RB-Tree, independent of
- * their hierarchy representation
- */
-
-struct mem_cgroup_tree_per_node {
-	struct rb_root rb_root;
-	struct rb_node *rb_rightmost;
-	spinlock_t lock;
-};
-
-struct mem_cgroup_tree {
-	struct mem_cgroup_tree_per_node *rb_tree_per_node[MAX_NUMNODES];
-};
-
-static struct mem_cgroup_tree soft_limit_tree __read_mostly;
-
-/* for OOM */
-struct mem_cgroup_eventfd_list {
-	struct list_head list;
-	struct eventfd_ctx *eventfd;
-};
-
-/*
- * cgroup_event represents events which userspace want to receive.
- */
-struct mem_cgroup_event {
-	/*
-	 * memcg which the event belongs to.
-	 */
-	struct mem_cgroup *memcg;
-	/*
-	 * eventfd to signal userspace about the event.
-	 */
-	struct eventfd_ctx *eventfd;
-	/*
-	 * Each of these stored in a list by the cgroup.
-	 */
-	struct list_head list;
-	/*
-	 * register_event() callback will be used to add new userspace
-	 * waiter for changes related to this event.  Use eventfd_signal()
-	 * on eventfd to send notification to userspace.
-	 */
-	int (*register_event)(struct mem_cgroup *memcg,
-			      struct eventfd_ctx *eventfd, const char *args);
-	/*
-	 * unregister_event() callback will be called when userspace closes
-	 * the eventfd or on cgroup removing.  This callback must be set,
-	 * if you want provide notification functionality.
-	 */
-	void (*unregister_event)(struct mem_cgroup *memcg,
-				 struct eventfd_ctx *eventfd);
-	/*
-	 * All fields below needed to unregister event when
-	 * userspace closes eventfd.
-	 */
-	poll_table pt;
-	wait_queue_head_t *wqh;
-	wait_queue_entry_t wait;
-	struct work_struct remove;
-};
-
-static void mem_cgroup_threshold(struct mem_cgroup *memcg);
-static void mem_cgroup_oom_notify(struct mem_cgroup *memcg);
-
-/* Stuffs for move charges at task migration. */
-/*
- * Types of charges to be moved.
- */
-#define MOVE_ANON	0x1U
-#define MOVE_FILE	0x2U
-#define MOVE_MASK	(MOVE_ANON | MOVE_FILE)
-
-/* "mc" and its members are protected by cgroup_mutex */
-static struct move_charge_struct {
-	spinlock_t	  lock; /* for from, to */
-	struct mm_struct  *mm;
-	struct mem_cgroup *from;
-	struct mem_cgroup *to;
-	unsigned long flags;
-	unsigned long precharge;
-	unsigned long moved_charge;
-	unsigned long moved_swap;
-	struct task_struct *moving_task;	/* a task moving charges */
-	wait_queue_head_t waitq;		/* a waitq for other context */
-} mc = {
-	.lock = __SPIN_LOCK_UNLOCKED(mc.lock),
-	.waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq),
-};
-
-/*
- * Maximum loops in mem_cgroup_soft_reclaim(), used for soft
- * limit reclaim to prevent infinite loops, if they ever occur.
- */
-#define	MEM_CGROUP_MAX_RECLAIM_LOOPS		100
-#define	MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS	2
-
-/* for encoding cft->private value on file */
-enum res_type {
-	_MEM,
-	_MEMSWAP,
-	_KMEM,
-	_TCP,
-};
-
-#define MEMFILE_PRIVATE(x, val)	((x) << 16 | (val))
-#define MEMFILE_TYPE(val)	((val) >> 16 & 0xffff)
-#define MEMFILE_ATTR(val)	((val) & 0xffff)
-
-/*
- * Iteration constructs for visiting all cgroups (under a tree).  If
- * loops are exited prematurely (break), mem_cgroup_iter_break() must
- * be used for reference counting.
- */
-#define for_each_mem_cgroup_tree(iter, root)		\
-	for (iter = mem_cgroup_iter(root, NULL, NULL);	\
-	     iter != NULL;				\
-	     iter = mem_cgroup_iter(root, iter, NULL))
-
-#define for_each_mem_cgroup(iter)			\
-	for (iter = mem_cgroup_iter(NULL, NULL, NULL);	\
-	     iter != NULL;				\
-	     iter = mem_cgroup_iter(NULL, iter, NULL))
-
 static inline bool task_is_dying(void)
 {
 	return tsk_is_oom_victim(current) || fatal_signal_pending(current) ||
@@ -254,7 +118,6 @@ struct mem_cgroup *vmpressure_to_memcg(struct vmpressure *vmpr)
 #define CURRENT_OBJCG_UPDATE_BIT 0
 #define CURRENT_OBJCG_UPDATE_FLAG (1UL << CURRENT_OBJCG_UPDATE_BIT)
 
-#ifdef CONFIG_MEMCG_KMEM
 static DEFINE_SPINLOCK(objcg_lock);
 
 bool mem_cgroup_kmem_disabled(void)
@@ -359,7 +222,6 @@ EXPORT_SYMBOL(memcg_kmem_online_key);
 
 DEFINE_STATIC_KEY_FALSE(memcg_bpf_enabled_key);
 EXPORT_SYMBOL(memcg_bpf_enabled_key);
-#endif
 
 /**
  * mem_cgroup_css_from_folio - css of the memcg associated with a folio
@@ -412,169 +274,6 @@ ino_t page_cgroup_ino(struct page *page)
 	return ino;
 }
 
-static void __mem_cgroup_insert_exceeded(struct mem_cgroup_per_node *mz,
-					 struct mem_cgroup_tree_per_node *mctz,
-					 unsigned long new_usage_in_excess)
-{
-	struct rb_node **p = &mctz->rb_root.rb_node;
-	struct rb_node *parent = NULL;
-	struct mem_cgroup_per_node *mz_node;
-	bool rightmost = true;
-
-	if (mz->on_tree)
-		return;
-
-	mz->usage_in_excess = new_usage_in_excess;
-	if (!mz->usage_in_excess)
-		return;
-	while (*p) {
-		parent = *p;
-		mz_node = rb_entry(parent, struct mem_cgroup_per_node,
-					tree_node);
-		if (mz->usage_in_excess < mz_node->usage_in_excess) {
-			p = &(*p)->rb_left;
-			rightmost = false;
-		} else {
-			p = &(*p)->rb_right;
-		}
-	}
-
-	if (rightmost)
-		mctz->rb_rightmost = &mz->tree_node;
-
-	rb_link_node(&mz->tree_node, parent, p);
-	rb_insert_color(&mz->tree_node, &mctz->rb_root);
-	mz->on_tree = true;
-}
-
-static void __mem_cgroup_remove_exceeded(struct mem_cgroup_per_node *mz,
-					 struct mem_cgroup_tree_per_node *mctz)
-{
-	if (!mz->on_tree)
-		return;
-
-	if (&mz->tree_node == mctz->rb_rightmost)
-		mctz->rb_rightmost = rb_prev(&mz->tree_node);
-
-	rb_erase(&mz->tree_node, &mctz->rb_root);
-	mz->on_tree = false;
-}
-
-static void mem_cgroup_remove_exceeded(struct mem_cgroup_per_node *mz,
-				       struct mem_cgroup_tree_per_node *mctz)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&mctz->lock, flags);
-	__mem_cgroup_remove_exceeded(mz, mctz);
-	spin_unlock_irqrestore(&mctz->lock, flags);
-}
-
-static unsigned long soft_limit_excess(struct mem_cgroup *memcg)
-{
-	unsigned long nr_pages = page_counter_read(&memcg->memory);
-	unsigned long soft_limit = READ_ONCE(memcg->soft_limit);
-	unsigned long excess = 0;
-
-	if (nr_pages > soft_limit)
-		excess = nr_pages - soft_limit;
-
-	return excess;
-}
-
-static void mem_cgroup_update_tree(struct mem_cgroup *memcg, int nid)
-{
-	unsigned long excess;
-	struct mem_cgroup_per_node *mz;
-	struct mem_cgroup_tree_per_node *mctz;
-
-	if (lru_gen_enabled()) {
-		if (soft_limit_excess(memcg))
-			lru_gen_soft_reclaim(memcg, nid);
-		return;
-	}
-
-	mctz = soft_limit_tree.rb_tree_per_node[nid];
-	if (!mctz)
-		return;
-	/*
-	 * Necessary to update all ancestors when hierarchy is used.
-	 * because their event counter is not touched.
-	 */
-	for (; memcg; memcg = parent_mem_cgroup(memcg)) {
-		mz = memcg->nodeinfo[nid];
-		excess = soft_limit_excess(memcg);
-		/*
-		 * We have to update the tree if mz is on RB-tree or
-		 * mem is over its softlimit.
-		 */
-		if (excess || mz->on_tree) {
-			unsigned long flags;
-
-			spin_lock_irqsave(&mctz->lock, flags);
-			/* if on-tree, remove it */
-			if (mz->on_tree)
-				__mem_cgroup_remove_exceeded(mz, mctz);
-			/*
-			 * Insert again. mz->usage_in_excess will be updated.
-			 * If excess is 0, no tree ops.
-			 */
-			__mem_cgroup_insert_exceeded(mz, mctz, excess);
-			spin_unlock_irqrestore(&mctz->lock, flags);
-		}
-	}
-}
-
-static void mem_cgroup_remove_from_trees(struct mem_cgroup *memcg)
-{
-	struct mem_cgroup_tree_per_node *mctz;
-	struct mem_cgroup_per_node *mz;
-	int nid;
-
-	for_each_node(nid) {
-		mz = memcg->nodeinfo[nid];
-		mctz = soft_limit_tree.rb_tree_per_node[nid];
-		if (mctz)
-			mem_cgroup_remove_exceeded(mz, mctz);
-	}
-}
-
-static struct mem_cgroup_per_node *
-__mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz)
-{
-	struct mem_cgroup_per_node *mz;
-
-retry:
-	mz = NULL;
-	if (!mctz->rb_rightmost)
-		goto done;		/* Nothing to reclaim from */
-
-	mz = rb_entry(mctz->rb_rightmost,
-		      struct mem_cgroup_per_node, tree_node);
-	/*
-	 * Remove the node now but someone else can add it back,
-	 * we will to add it back at the end of reclaim to its correct
-	 * position in the tree.
-	 */
-	__mem_cgroup_remove_exceeded(mz, mctz);
-	if (!soft_limit_excess(mz->memcg) ||
-	    !css_tryget(&mz->memcg->css))
-		goto retry;
-done:
-	return mz;
-}
-
-static struct mem_cgroup_per_node *
-mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz)
-{
-	struct mem_cgroup_per_node *mz;
-
-	spin_lock_irq(&mctz->lock);
-	mz = __mem_cgroup_largest_soft_limit_node(mctz);
-	spin_unlock_irq(&mctz->lock);
-	return mz;
-}
-
 /* Subset of node_stat_item for memcg stats */
 static const unsigned int memcg_node_stat_items[] = {
 	NR_INACTIVE_ANON,
@@ -722,7 +421,7 @@ static const unsigned int memcg_vm_event_stat[] = {
 	PGDEACTIVATE,
 	PGLAZYFREE,
 	PGLAZYFREED,
-#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP)
+#ifdef CONFIG_ZSWAP
 	ZSWPIN,
 	ZSWPOUT,
 	ZSWPWB,
@@ -971,7 +670,7 @@ void __mod_memcg_state(struct mem_cgroup *memcg, enum memcg_stat_item idx,
 }
 
 /* idx can be of type enum memcg_stat_item or node_stat_item. */
-static unsigned long memcg_page_state_local(struct mem_cgroup *memcg, int idx)
+unsigned long memcg_page_state_local(struct mem_cgroup *memcg, int idx)
 {
 	long x;
 	int i = memcg_stats_index(idx);
@@ -1120,7 +819,7 @@ void __count_memcg_events(struct mem_cgroup *memcg, enum vm_event_item idx,
 	memcg_stats_unlock();
 }
 
-static unsigned long memcg_events(struct mem_cgroup *memcg, int event)
+unsigned long memcg_events(struct mem_cgroup *memcg, int event)
 {
 	int i = memcg_events_index(event);
 
@@ -1130,7 +829,7 @@ static unsigned long memcg_events(struct mem_cgroup *memcg, int event)
 	return READ_ONCE(memcg->vmstats->events[i]);
 }
 
-static unsigned long memcg_events_local(struct mem_cgroup *memcg, int event)
+unsigned long memcg_events_local(struct mem_cgroup *memcg, int event)
 {
 	int i = memcg_events_index(event);
 
@@ -1140,8 +839,7 @@ static unsigned long memcg_events_local(struct mem_cgroup *memcg, int event)
 	return READ_ONCE(memcg->vmstats->events_local[i]);
 }
 
-static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg,
-					 int nr_pages)
+void mem_cgroup_charge_statistics(struct mem_cgroup *memcg, int nr_pages)
 {
 	/* pagein of a big page is an event. So, ignore page size */
 	if (nr_pages > 0)
@@ -1154,8 +852,8 @@ static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg,
 	__this_cpu_add(memcg->vmstats_percpu->nr_page_events, nr_pages);
 }
 
-static bool mem_cgroup_event_ratelimit(struct mem_cgroup *memcg,
-				       enum mem_cgroup_events_target target)
+bool mem_cgroup_event_ratelimit(struct mem_cgroup *memcg,
+				enum mem_cgroup_events_target target)
 {
 	unsigned long val, next;
 
@@ -1179,28 +877,6 @@ static bool mem_cgroup_event_ratelimit(struct mem_cgroup *memcg,
 	return false;
 }
 
-/*
- * Check events in order.
- *
- */
-static void memcg_check_events(struct mem_cgroup *memcg, int nid)
-{
-	if (IS_ENABLED(CONFIG_PREEMPT_RT))
-		return;
-
-	/* threshold event is triggered in finer grain than soft limit */
-	if (unlikely(mem_cgroup_event_ratelimit(memcg,
-						MEM_CGROUP_TARGET_THRESH))) {
-		bool do_softlimit;
-
-		do_softlimit = mem_cgroup_event_ratelimit(memcg,
-						MEM_CGROUP_TARGET_SOFTLIMIT);
-		mem_cgroup_threshold(memcg);
-		if (unlikely(do_softlimit))
-			mem_cgroup_update_tree(memcg, nid);
-	}
-}
-
 struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p)
 {
 	/*
@@ -1652,51 +1328,6 @@ static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg)
 	return margin;
 }
 
-/*
- * A routine for checking "mem" is under move_account() or not.
- *
- * Checking a cgroup is mc.from or mc.to or under hierarchy of
- * moving cgroups. This is for waiting at high-memory pressure
- * caused by "move".
- */
-static bool mem_cgroup_under_move(struct mem_cgroup *memcg)
-{
-	struct mem_cgroup *from;
-	struct mem_cgroup *to;
-	bool ret = false;
-	/*
-	 * Unlike task_move routines, we access mc.to, mc.from not under
-	 * mutual exclusion by cgroup_mutex. Here, we take spinlock instead.
-	 */
-	spin_lock(&mc.lock);
-	from = mc.from;
-	to = mc.to;
-	if (!from)
-		goto unlock;
-
-	ret = mem_cgroup_is_descendant(from, memcg) ||
-		mem_cgroup_is_descendant(to, memcg);
-unlock:
-	spin_unlock(&mc.lock);
-	return ret;
-}
-
-static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg)
-{
-	if (mc.moving_task && current != mc.moving_task) {
-		if (mem_cgroup_under_move(memcg)) {
-			DEFINE_WAIT(wait);
-			prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE);
-			/* moving charge context might have finished. */
-			if (mc.moving_task)
-				schedule();
-			finish_wait(&mc.waitq, &wait);
-			return true;
-		}
-	}
-	return false;
-}
-
 struct memory_stat {
 	const char *name;
 	unsigned int idx;
@@ -1713,7 +1344,7 @@ static const struct memory_stat memory_stats[] = {
 	{ "sock",			MEMCG_SOCK			},
 	{ "vmalloc",			MEMCG_VMALLOC			},
 	{ "shmem",			NR_SHMEM			},
-#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP)
+#ifdef CONFIG_ZSWAP
 	{ "zswap",			MEMCG_ZSWAP_B			},
 	{ "zswapped",			MEMCG_ZSWAPPED			},
 #endif
@@ -1783,15 +1414,13 @@ static int memcg_page_state_output_unit(int item)
 	}
 }
 
-static inline unsigned long memcg_page_state_output(struct mem_cgroup *memcg,
-						    int item)
+unsigned long memcg_page_state_output(struct mem_cgroup *memcg, int item)
 {
 	return memcg_page_state(memcg, item) *
 		memcg_page_state_output_unit(item);
 }
 
-static inline unsigned long memcg_page_state_local_output(
-		struct mem_cgroup *memcg, int item)
+unsigned long memcg_page_state_local_output(struct mem_cgroup *memcg, int item)
 {
 	return memcg_page_state_local(memcg, item) *
 		memcg_page_state_output_unit(item);
@@ -1845,20 +1474,16 @@ static void memcg_stat_format(struct mem_cgroup *memcg, struct seq_buf *s)
 			       vm_event_name(memcg_vm_event_stat[i]),
 			       memcg_events(memcg, memcg_vm_event_stat[i]));
 	}
-
-	/* The above should easily fit into one page */
-	WARN_ON_ONCE(seq_buf_has_overflowed(s));
 }
 
-static void memcg1_stat_format(struct mem_cgroup *memcg, struct seq_buf *s);
-
 static void memory_stat_format(struct mem_cgroup *memcg, struct seq_buf *s)
 {
 	if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
 		memcg_stat_format(memcg, s);
 	else
 		memcg1_stat_format(memcg, s);
-	WARN_ON_ONCE(seq_buf_has_overflowed(s));
+	if (seq_buf_has_overflowed(s))
+		pr_warn("%s: Warning, stat buffer overflow, please report\n", __func__);
 }
 
 /**
@@ -1906,6 +1531,7 @@ void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg)
 		pr_info("swap: usage %llukB, limit %llukB, failcnt %lu\n",
 			K((u64)page_counter_read(&memcg->swap)),
 			K((u64)READ_ONCE(memcg->swap.max)), memcg->swap.failcnt);
+#ifdef CONFIG_MEMCG_V1
 	else {
 		pr_info("memory+swap: usage %llukB, limit %llukB, failcnt %lu\n",
 			K((u64)page_counter_read(&memcg->memsw)),
@@ -1914,6 +1540,7 @@ void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg)
 			K((u64)page_counter_read(&memcg->kmem)),
 			K((u64)memcg->kmem.max), memcg->kmem.failcnt);
 	}
+#endif
 
 	pr_info("Memory cgroup stats for ");
 	pr_cont_cgroup_path(memcg->css.cgroup);
@@ -1979,180 +1606,6 @@ unlock:
 	return ret;
 }
 
-static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg,
-				   pg_data_t *pgdat,
-				   gfp_t gfp_mask,
-				   unsigned long *total_scanned)
-{
-	struct mem_cgroup *victim = NULL;
-	int total = 0;
-	int loop = 0;
-	unsigned long excess;
-	unsigned long nr_scanned;
-	struct mem_cgroup_reclaim_cookie reclaim = {
-		.pgdat = pgdat,
-	};
-
-	excess = soft_limit_excess(root_memcg);
-
-	while (1) {
-		victim = mem_cgroup_iter(root_memcg, victim, &reclaim);
-		if (!victim) {
-			loop++;
-			if (loop >= 2) {
-				/*
-				 * If we have not been able to reclaim
-				 * anything, it might because there are
-				 * no reclaimable pages under this hierarchy
-				 */
-				if (!total)
-					break;
-				/*
-				 * We want to do more targeted reclaim.
-				 * excess >> 2 is not to excessive so as to
-				 * reclaim too much, nor too less that we keep
-				 * coming back to reclaim from this cgroup
-				 */
-				if (total >= (excess >> 2) ||
-					(loop > MEM_CGROUP_MAX_RECLAIM_LOOPS))
-					break;
-			}
-			continue;
-		}
-		total += mem_cgroup_shrink_node(victim, gfp_mask, false,
-					pgdat, &nr_scanned);
-		*total_scanned += nr_scanned;
-		if (!soft_limit_excess(root_memcg))
-			break;
-	}
-	mem_cgroup_iter_break(root_memcg, victim);
-	return total;
-}
-
-#ifdef CONFIG_LOCKDEP
-static struct lockdep_map memcg_oom_lock_dep_map = {
-	.name = "memcg_oom_lock",
-};
-#endif
-
-static DEFINE_SPINLOCK(memcg_oom_lock);
-
-/*
- * Check OOM-Killer is already running under our hierarchy.
- * If someone is running, return false.
- */
-static bool mem_cgroup_oom_trylock(struct mem_cgroup *memcg)
-{
-	struct mem_cgroup *iter, *failed = NULL;
-
-	spin_lock(&memcg_oom_lock);
-
-	for_each_mem_cgroup_tree(iter, memcg) {
-		if (iter->oom_lock) {
-			/*
-			 * this subtree of our hierarchy is already locked
-			 * so we cannot give a lock.
-			 */
-			failed = iter;
-			mem_cgroup_iter_break(memcg, iter);
-			break;
-		} else
-			iter->oom_lock = true;
-	}
-
-	if (failed) {
-		/*
-		 * OK, we failed to lock the whole subtree so we have
-		 * to clean up what we set up to the failing subtree
-		 */
-		for_each_mem_cgroup_tree(iter, memcg) {
-			if (iter == failed) {
-				mem_cgroup_iter_break(memcg, iter);
-				break;
-			}
-			iter->oom_lock = false;
-		}
-	} else
-		mutex_acquire(&memcg_oom_lock_dep_map, 0, 1, _RET_IP_);
-
-	spin_unlock(&memcg_oom_lock);
-
-	return !failed;
-}
-
-static void mem_cgroup_oom_unlock(struct mem_cgroup *memcg)
-{
-	struct mem_cgroup *iter;
-
-	spin_lock(&memcg_oom_lock);
-	mutex_release(&memcg_oom_lock_dep_map, _RET_IP_);
-	for_each_mem_cgroup_tree(iter, memcg)
-		iter->oom_lock = false;
-	spin_unlock(&memcg_oom_lock);
-}
-
-static void mem_cgroup_mark_under_oom(struct mem_cgroup *memcg)
-{
-	struct mem_cgroup *iter;
-
-	spin_lock(&memcg_oom_lock);
-	for_each_mem_cgroup_tree(iter, memcg)
-		iter->under_oom++;
-	spin_unlock(&memcg_oom_lock);
-}
-
-static void mem_cgroup_unmark_under_oom(struct mem_cgroup *memcg)
-{
-	struct mem_cgroup *iter;
-
-	/*
-	 * Be careful about under_oom underflows because a child memcg
-	 * could have been added after mem_cgroup_mark_under_oom.
-	 */
-	spin_lock(&memcg_oom_lock);
-	for_each_mem_cgroup_tree(iter, memcg)
-		if (iter->under_oom > 0)
-			iter->under_oom--;
-	spin_unlock(&memcg_oom_lock);
-}
-
-static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq);
-
-struct oom_wait_info {
-	struct mem_cgroup *memcg;
-	wait_queue_entry_t	wait;
-};
-
-static int memcg_oom_wake_function(wait_queue_entry_t *wait,
-	unsigned mode, int sync, void *arg)
-{
-	struct mem_cgroup *wake_memcg = (struct mem_cgroup *)arg;
-	struct mem_cgroup *oom_wait_memcg;
-	struct oom_wait_info *oom_wait_info;
-
-	oom_wait_info = container_of(wait, struct oom_wait_info, wait);
-	oom_wait_memcg = oom_wait_info->memcg;
-
-	if (!mem_cgroup_is_descendant(wake_memcg, oom_wait_memcg) &&
-	    !mem_cgroup_is_descendant(oom_wait_memcg, wake_memcg))
-		return 0;
-	return autoremove_wake_function(wait, mode, sync, arg);
-}
-
-static void memcg_oom_recover(struct mem_cgroup *memcg)
-{
-	/*
-	 * For the following lockless ->under_oom test, the only required
-	 * guarantee is that it must see the state asserted by an OOM when
-	 * this function is called as a result of userland actions
-	 * triggered by the notification of the OOM.  This is trivially
-	 * achieved by invoking mem_cgroup_mark_under_oom() before
-	 * triggering notification.
-	 */
-	if (memcg && memcg->under_oom)
-		__wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, memcg);
-}
-
 /*
  * Returns true if successfully killed one or more processes. Though in some
  * corner cases it can return true even without killing any process.
@@ -2166,105 +1619,17 @@ static bool mem_cgroup_oom(struct mem_cgroup *memcg, gfp_t mask, int order)
 
 	memcg_memory_event(memcg, MEMCG_OOM);
 
-	/*
-	 * We are in the middle of the charge context here, so we
-	 * don't want to block when potentially sitting on a callstack
-	 * that holds all kinds of filesystem and mm locks.
-	 *
-	 * cgroup1 allows disabling the OOM killer and waiting for outside
-	 * handling until the charge can succeed; remember the context and put
-	 * the task to sleep at the end of the page fault when all locks are
-	 * released.
-	 *
-	 * On the other hand, in-kernel OOM killer allows for an async victim
-	 * memory reclaim (oom_reaper) and that means that we are not solely
-	 * relying on the oom victim to make a forward progress and we can
-	 * invoke the oom killer here.
-	 *
-	 * Please note that mem_cgroup_out_of_memory might fail to find a
-	 * victim and then we have to bail out from the charge path.
-	 */
-	if (READ_ONCE(memcg->oom_kill_disable)) {
-		if (current->in_user_fault) {
-			css_get(&memcg->css);
-			current->memcg_in_oom = memcg;
-		}
+	if (!memcg1_oom_prepare(memcg, &locked))
 		return false;
-	}
-
-	mem_cgroup_mark_under_oom(memcg);
 
-	locked = mem_cgroup_oom_trylock(memcg);
-
-	if (locked)
-		mem_cgroup_oom_notify(memcg);
-
-	mem_cgroup_unmark_under_oom(memcg);
 	ret = mem_cgroup_out_of_memory(memcg, mask, order);
 
-	if (locked)
-		mem_cgroup_oom_unlock(memcg);
+	memcg1_oom_finish(memcg, locked);
 
 	return ret;
 }
 
 /**
- * mem_cgroup_oom_synchronize - complete memcg OOM handling
- * @handle: actually kill/wait or just clean up the OOM state
- *
- * This has to be called at the end of a page fault if the memcg OOM
- * handler was enabled.
- *
- * Memcg supports userspace OOM handling where failed allocations must
- * sleep on a waitqueue until the userspace task resolves the
- * situation.  Sleeping directly in the charge context with all kinds
- * of locks held is not a good idea, instead we remember an OOM state
- * in the task and mem_cgroup_oom_synchronize() has to be called at
- * the end of the page fault to complete the OOM handling.
- *
- * Returns %true if an ongoing memcg OOM situation was detected and
- * completed, %false otherwise.
- */
-bool mem_cgroup_oom_synchronize(bool handle)
-{
-	struct mem_cgroup *memcg = current->memcg_in_oom;
-	struct oom_wait_info owait;
-	bool locked;
-
-	/* OOM is global, do not handle */
-	if (!memcg)
-		return false;
-
-	if (!handle)
-		goto cleanup;
-
-	owait.memcg = memcg;
-	owait.wait.flags = 0;
-	owait.wait.func = memcg_oom_wake_function;
-	owait.wait.private = current;
-	INIT_LIST_HEAD(&owait.wait.entry);
-
-	prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE);
-	mem_cgroup_mark_under_oom(memcg);
-
-	locked = mem_cgroup_oom_trylock(memcg);
-
-	if (locked)
-		mem_cgroup_oom_notify(memcg);
-
-	schedule();
-	mem_cgroup_unmark_under_oom(memcg);
-	finish_wait(&memcg_oom_waitq, &owait.wait);
-
-	if (locked)
-		mem_cgroup_oom_unlock(memcg);
-cleanup:
-	current->memcg_in_oom = NULL;
-	css_put(&memcg->css);
-	return true;
-}
-
-/**
  * mem_cgroup_get_oom_group - get a memory cgroup to clean up after OOM
  * @victim: task to be killed by the OOM killer
  * @oom_domain: memcg in case of memcg OOM, NULL in case of system-wide OOM
@@ -2328,99 +1693,16 @@ void mem_cgroup_print_oom_group(struct mem_cgroup *memcg)
 	pr_cont(" are going to be killed due to memory.oom.group set\n");
 }
 
-/**
- * folio_memcg_lock - Bind a folio to its memcg.
- * @folio: The folio.
- *
- * This function prevents unlocked LRU folios from being moved to
- * another cgroup.
- *
- * It ensures lifetime of the bound memcg.  The caller is responsible
- * for the lifetime of the folio.
- */
-void folio_memcg_lock(struct folio *folio)
-{
-	struct mem_cgroup *memcg;
-	unsigned long flags;
-
-	/*
-	 * The RCU lock is held throughout the transaction.  The fast
-	 * path can get away without acquiring the memcg->move_lock
-	 * because page moving starts with an RCU grace period.
-         */
-	rcu_read_lock();
-
-	if (mem_cgroup_disabled())
-		return;
-again:
-	memcg = folio_memcg(folio);
-	if (unlikely(!memcg))
-		return;
-
-#ifdef CONFIG_PROVE_LOCKING
-	local_irq_save(flags);
-	might_lock(&memcg->move_lock);
-	local_irq_restore(flags);
-#endif
-
-	if (atomic_read(&memcg->moving_account) <= 0)
-		return;
-
-	spin_lock_irqsave(&memcg->move_lock, flags);
-	if (memcg != folio_memcg(folio)) {
-		spin_unlock_irqrestore(&memcg->move_lock, flags);
-		goto again;
-	}
-
-	/*
-	 * When charge migration first begins, we can have multiple
-	 * critical sections holding the fast-path RCU lock and one
-	 * holding the slowpath move_lock. Track the task who has the
-	 * move_lock for folio_memcg_unlock().
-	 */
-	memcg->move_lock_task = current;
-	memcg->move_lock_flags = flags;
-}
-
-static void __folio_memcg_unlock(struct mem_cgroup *memcg)
-{
-	if (memcg && memcg->move_lock_task == current) {
-		unsigned long flags = memcg->move_lock_flags;
-
-		memcg->move_lock_task = NULL;
-		memcg->move_lock_flags = 0;
-
-		spin_unlock_irqrestore(&memcg->move_lock, flags);
-	}
-
-	rcu_read_unlock();
-}
-
-/**
- * folio_memcg_unlock - Release the binding between a folio and its memcg.
- * @folio: The folio.
- *
- * This releases the binding created by folio_memcg_lock().  This does
- * not change the accounting of this folio to its memcg, but it does
- * permit others to change it.
- */
-void folio_memcg_unlock(struct folio *folio)
-{
-	__folio_memcg_unlock(folio_memcg(folio));
-}
-
 struct memcg_stock_pcp {
 	local_lock_t stock_lock;
 	struct mem_cgroup *cached; /* this never be root cgroup */
 	unsigned int nr_pages;
 
-#ifdef CONFIG_MEMCG_KMEM
 	struct obj_cgroup *cached_objcg;
 	struct pglist_data *cached_pgdat;
 	unsigned int nr_bytes;
 	int nr_slab_reclaimable_b;
 	int nr_slab_unreclaimable_b;
-#endif
 
 	struct work_struct work;
 	unsigned long flags;
@@ -2431,26 +1713,9 @@ static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock) = {
 };
 static DEFINE_MUTEX(percpu_charge_mutex);
 
-#ifdef CONFIG_MEMCG_KMEM
 static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock);
 static bool obj_stock_flush_required(struct memcg_stock_pcp *stock,
 				     struct mem_cgroup *root_memcg);
-static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages);
-
-#else
-static inline struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock)
-{
-	return NULL;
-}
-static bool obj_stock_flush_required(struct memcg_stock_pcp *stock,
-				     struct mem_cgroup *root_memcg)
-{
-	return false;
-}
-static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages)
-{
-}
-#endif
 
 /**
  * consume_stock: Try to consume stocked charge on this cpu.
@@ -2567,7 +1832,7 @@ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
  * Drains all per-CPU charge caches for given root_memcg resp. subtree
  * of the hierarchy under it.
  */
-static void drain_all_stock(struct mem_cgroup *root_memcg)
+void drain_all_stock(struct mem_cgroup *root_memcg)
 {
 	int cpu, curcpu;
 
@@ -2636,7 +1901,8 @@ static unsigned long reclaim_high(struct mem_cgroup *memcg,
 		psi_memstall_enter(&pflags);
 		nr_reclaimed += try_to_free_mem_cgroup_pages(memcg, nr_pages,
 							gfp_mask,
-							MEMCG_RECLAIM_MAY_SWAP);
+							MEMCG_RECLAIM_MAY_SWAP,
+							NULL);
 		psi_memstall_leave(&pflags);
 	} while ((memcg = parent_mem_cgroup(memcg)) &&
 		 !mem_cgroup_is_root(memcg));
@@ -2887,8 +2153,8 @@ out:
 	css_put(&memcg->css);
 }
 
-static int try_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp_mask,
-			unsigned int nr_pages)
+int try_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp_mask,
+		     unsigned int nr_pages)
 {
 	unsigned int batch = max(MEMCG_CHARGE_BATCH, nr_pages);
 	int nr_retries = MAX_RECLAIM_RETRIES;
@@ -2942,7 +2208,7 @@ retry:
 
 	psi_memstall_enter(&pflags);
 	nr_reclaimed = try_to_free_mem_cgroup_pages(mem_over_limit, nr_pages,
-						    gfp_mask, reclaim_options);
+						    gfp_mask, reclaim_options, NULL);
 	psi_memstall_leave(&pflags);
 
 	if (mem_cgroup_margin(mem_over_limit) >= nr_pages)
@@ -2971,7 +2237,7 @@ retry:
 	 * At task move, charge accounts can be doubly counted. So, it's
 	 * better to wait until the end of task_move if something is going on.
 	 */
-	if (mem_cgroup_wait_acct_move(mem_over_limit))
+	if (memcg1_wait_acct_move(mem_over_limit))
 		goto retry;
 
 	if (nr_retries--)
@@ -3083,15 +2349,6 @@ done_restock:
 	return 0;
 }
 
-static inline int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask,
-			     unsigned int nr_pages)
-{
-	if (mem_cgroup_is_root(memcg))
-		return 0;
-
-	return try_charge_memcg(memcg, gfp_mask, nr_pages);
-}
-
 /**
  * mem_cgroup_cancel_charge() - cancel an uncommitted try_charge() call.
  * @memcg: memcg previously charged.
@@ -3134,12 +2391,10 @@ void mem_cgroup_commit_charge(struct folio *folio, struct mem_cgroup *memcg)
 
 	local_irq_disable();
 	mem_cgroup_charge_statistics(memcg, folio_nr_pages(folio));
-	memcg_check_events(memcg, folio_nid(folio));
+	memcg1_check_events(memcg, folio_nid(folio));
 	local_irq_enable();
 }
 
-#ifdef CONFIG_MEMCG_KMEM
-
 static inline void __mod_objcg_mlstate(struct obj_cgroup *objcg,
 				       struct pglist_data *pgdat,
 				       enum node_stat_item idx, int nr)
@@ -3367,18 +2622,6 @@ struct obj_cgroup *get_obj_cgroup_from_folio(struct folio *folio)
 	return objcg;
 }
 
-static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages)
-{
-	mod_memcg_state(memcg, MEMCG_KMEM, nr_pages);
-	if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) {
-		if (nr_pages > 0)
-			page_counter_charge(&memcg->kmem, nr_pages);
-		else
-			page_counter_uncharge(&memcg->kmem, -nr_pages);
-	}
-}
-
-
 /*
  * obj_cgroup_uncharge_pages: uncharge a number of kernel pages from a objcg
  * @objcg: object cgroup to uncharge
@@ -3391,7 +2634,8 @@ static void obj_cgroup_uncharge_pages(struct obj_cgroup *objcg,
 
 	memcg = get_mem_cgroup_from_objcg(objcg);
 
-	memcg_account_kmem(memcg, -nr_pages);
+	mod_memcg_state(memcg, MEMCG_KMEM, -nr_pages);
+	memcg1_account_kmem(memcg, -nr_pages);
 	refill_stock(memcg, nr_pages);
 
 	css_put(&memcg->css);
@@ -3417,7 +2661,8 @@ static int obj_cgroup_charge_pages(struct obj_cgroup *objcg, gfp_t gfp,
 	if (ret)
 		goto out;
 
-	memcg_account_kmem(memcg, nr_pages);
+	mod_memcg_state(memcg, MEMCG_KMEM, nr_pages);
+	memcg1_account_kmem(memcg, nr_pages);
 out:
 	css_put(&memcg->css);
 
@@ -3570,7 +2815,8 @@ static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock)
 
 			memcg = get_mem_cgroup_from_objcg(old);
 
-			memcg_account_kmem(memcg, -nr_pages);
+			mod_memcg_state(memcg, MEMCG_KMEM, -nr_pages);
+			memcg1_account_kmem(memcg, -nr_pages);
 			__refill_stock(memcg, nr_pages);
 
 			css_put(&memcg->css);
@@ -3804,10 +3050,9 @@ void __memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab,
 		obj_cgroup_put(objcg);
 	}
 }
-#endif /* CONFIG_MEMCG_KMEM */
 
 /*
- * Because page_memcg(head) is not set on tails, set it now.
+ * Because folio_memcg(head) is not set on tails, set it now.
  */
 void split_page_memcg(struct page *head, int old_order, int new_order)
 {
@@ -3829,240 +3074,7 @@ void split_page_memcg(struct page *head, int old_order, int new_order)
 		css_get_many(&memcg->css, old_nr / new_nr - 1);
 }
 
-#ifdef CONFIG_SWAP
-/**
- * mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record.
- * @entry: swap entry to be moved
- * @from:  mem_cgroup which the entry is moved from
- * @to:  mem_cgroup which the entry is moved to
- *
- * It succeeds only when the swap_cgroup's record for this entry is the same
- * as the mem_cgroup's id of @from.
- *
- * Returns 0 on success, -EINVAL on failure.
- *
- * The caller must have charged to @to, IOW, called page_counter_charge() about
- * both res and memsw, and called css_get().
- */
-static int mem_cgroup_move_swap_account(swp_entry_t entry,
-				struct mem_cgroup *from, struct mem_cgroup *to)
-{
-	unsigned short old_id, new_id;
-
-	old_id = mem_cgroup_id(from);
-	new_id = mem_cgroup_id(to);
-
-	if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) {
-		mod_memcg_state(from, MEMCG_SWAP, -1);
-		mod_memcg_state(to, MEMCG_SWAP, 1);
-		return 0;
-	}
-	return -EINVAL;
-}
-#else
-static inline int mem_cgroup_move_swap_account(swp_entry_t entry,
-				struct mem_cgroup *from, struct mem_cgroup *to)
-{
-	return -EINVAL;
-}
-#endif
-
-static DEFINE_MUTEX(memcg_max_mutex);
-
-static int mem_cgroup_resize_max(struct mem_cgroup *memcg,
-				 unsigned long max, bool memsw)
-{
-	bool enlarge = false;
-	bool drained = false;
-	int ret;
-	bool limits_invariant;
-	struct page_counter *counter = memsw ? &memcg->memsw : &memcg->memory;
-
-	do {
-		if (signal_pending(current)) {
-			ret = -EINTR;
-			break;
-		}
-
-		mutex_lock(&memcg_max_mutex);
-		/*
-		 * Make sure that the new limit (memsw or memory limit) doesn't
-		 * break our basic invariant rule memory.max <= memsw.max.
-		 */
-		limits_invariant = memsw ? max >= READ_ONCE(memcg->memory.max) :
-					   max <= memcg->memsw.max;
-		if (!limits_invariant) {
-			mutex_unlock(&memcg_max_mutex);
-			ret = -EINVAL;
-			break;
-		}
-		if (max > counter->max)
-			enlarge = true;
-		ret = page_counter_set_max(counter, max);
-		mutex_unlock(&memcg_max_mutex);
-
-		if (!ret)
-			break;
-
-		if (!drained) {
-			drain_all_stock(memcg);
-			drained = true;
-			continue;
-		}
-
-		if (!try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL,
-					memsw ? 0 : MEMCG_RECLAIM_MAY_SWAP)) {
-			ret = -EBUSY;
-			break;
-		}
-	} while (true);
-
-	if (!ret && enlarge)
-		memcg_oom_recover(memcg);
-
-	return ret;
-}
-
-unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
-					    gfp_t gfp_mask,
-					    unsigned long *total_scanned)
-{
-	unsigned long nr_reclaimed = 0;
-	struct mem_cgroup_per_node *mz, *next_mz = NULL;
-	unsigned long reclaimed;
-	int loop = 0;
-	struct mem_cgroup_tree_per_node *mctz;
-	unsigned long excess;
-
-	if (lru_gen_enabled())
-		return 0;
-
-	if (order > 0)
-		return 0;
-
-	mctz = soft_limit_tree.rb_tree_per_node[pgdat->node_id];
-
-	/*
-	 * Do not even bother to check the largest node if the root
-	 * is empty. Do it lockless to prevent lock bouncing. Races
-	 * are acceptable as soft limit is best effort anyway.
-	 */
-	if (!mctz || RB_EMPTY_ROOT(&mctz->rb_root))
-		return 0;
-
-	/*
-	 * This loop can run a while, specially if mem_cgroup's continuously
-	 * keep exceeding their soft limit and putting the system under
-	 * pressure
-	 */
-	do {
-		if (next_mz)
-			mz = next_mz;
-		else
-			mz = mem_cgroup_largest_soft_limit_node(mctz);
-		if (!mz)
-			break;
-
-		reclaimed = mem_cgroup_soft_reclaim(mz->memcg, pgdat,
-						    gfp_mask, total_scanned);
-		nr_reclaimed += reclaimed;
-		spin_lock_irq(&mctz->lock);
-
-		/*
-		 * If we failed to reclaim anything from this memory cgroup
-		 * it is time to move on to the next cgroup
-		 */
-		next_mz = NULL;
-		if (!reclaimed)
-			next_mz = __mem_cgroup_largest_soft_limit_node(mctz);
-
-		excess = soft_limit_excess(mz->memcg);
-		/*
-		 * One school of thought says that we should not add
-		 * back the node to the tree if reclaim returns 0.
-		 * But our reclaim could return 0, simply because due
-		 * to priority we are exposing a smaller subset of
-		 * memory to reclaim from. Consider this as a longer
-		 * term TODO.
-		 */
-		/* If excess == 0, no tree ops */
-		__mem_cgroup_insert_exceeded(mz, mctz, excess);
-		spin_unlock_irq(&mctz->lock);
-		css_put(&mz->memcg->css);
-		loop++;
-		/*
-		 * Could not reclaim anything and there are no more
-		 * mem cgroups to try or we seem to be looping without
-		 * reclaiming anything.
-		 */
-		if (!nr_reclaimed &&
-			(next_mz == NULL ||
-			loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS))
-			break;
-	} while (!nr_reclaimed);
-	if (next_mz)
-		css_put(&next_mz->memcg->css);
-	return nr_reclaimed;
-}
-
-/*
- * Reclaims as many pages from the given memcg as possible.
- *
- * Caller is responsible for holding css reference for memcg.
- */
-static int mem_cgroup_force_empty(struct mem_cgroup *memcg)
-{
-	int nr_retries = MAX_RECLAIM_RETRIES;
-
-	/* we call try-to-free pages for make this cgroup empty */
-	lru_add_drain_all();
-
-	drain_all_stock(memcg);
-
-	/* try to free all pages in this cgroup */
-	while (nr_retries && page_counter_read(&memcg->memory)) {
-		if (signal_pending(current))
-			return -EINTR;
-
-		if (!try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL,
-						  MEMCG_RECLAIM_MAY_SWAP))
-			nr_retries--;
-	}
-
-	return 0;
-}
-
-static ssize_t mem_cgroup_force_empty_write(struct kernfs_open_file *of,
-					    char *buf, size_t nbytes,
-					    loff_t off)
-{
-	struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
-
-	if (mem_cgroup_is_root(memcg))
-		return -EINVAL;
-	return mem_cgroup_force_empty(memcg) ?: nbytes;
-}
-
-static u64 mem_cgroup_hierarchy_read(struct cgroup_subsys_state *css,
-				     struct cftype *cft)
-{
-	return 1;
-}
-
-static int mem_cgroup_hierarchy_write(struct cgroup_subsys_state *css,
-				      struct cftype *cft, u64 val)
-{
-	if (val == 1)
-		return 0;
-
-	pr_warn_once("Non-hierarchical mode is deprecated. "
-		     "Please report your usecase to linux-mm@kvack.org if you "
-		     "depend on this functionality.\n");
-
-	return -EINVAL;
-}
-
-static unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap)
+unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap)
 {
 	unsigned long val;
 
@@ -4084,68 +3096,6 @@ static unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap)
 	return val;
 }
 
-enum {
-	RES_USAGE,
-	RES_LIMIT,
-	RES_MAX_USAGE,
-	RES_FAILCNT,
-	RES_SOFT_LIMIT,
-};
-
-static u64 mem_cgroup_read_u64(struct cgroup_subsys_state *css,
-			       struct cftype *cft)
-{
-	struct mem_cgroup *memcg = mem_cgroup_from_css(css);
-	struct page_counter *counter;
-
-	switch (MEMFILE_TYPE(cft->private)) {
-	case _MEM:
-		counter = &memcg->memory;
-		break;
-	case _MEMSWAP:
-		counter = &memcg->memsw;
-		break;
-	case _KMEM:
-		counter = &memcg->kmem;
-		break;
-	case _TCP:
-		counter = &memcg->tcpmem;
-		break;
-	default:
-		BUG();
-	}
-
-	switch (MEMFILE_ATTR(cft->private)) {
-	case RES_USAGE:
-		if (counter == &memcg->memory)
-			return (u64)mem_cgroup_usage(memcg, false) * PAGE_SIZE;
-		if (counter == &memcg->memsw)
-			return (u64)mem_cgroup_usage(memcg, true) * PAGE_SIZE;
-		return (u64)page_counter_read(counter) * PAGE_SIZE;
-	case RES_LIMIT:
-		return (u64)counter->max * PAGE_SIZE;
-	case RES_MAX_USAGE:
-		return (u64)counter->watermark * PAGE_SIZE;
-	case RES_FAILCNT:
-		return counter->failcnt;
-	case RES_SOFT_LIMIT:
-		return (u64)READ_ONCE(memcg->soft_limit) * PAGE_SIZE;
-	default:
-		BUG();
-	}
-}
-
-/*
- * This function doesn't do anything useful. Its only job is to provide a read
- * handler for a file so that cgroup_file_mode() will add read permissions.
- */
-static int mem_cgroup_dummy_seq_show(__always_unused struct seq_file *m,
-				     __always_unused void *v)
-{
-	return -EINVAL;
-}
-
-#ifdef CONFIG_MEMCG_KMEM
 static int memcg_online_kmem(struct mem_cgroup *memcg)
 {
 	struct obj_cgroup *objcg;
@@ -4196,760 +3146,6 @@ static void memcg_offline_kmem(struct mem_cgroup *memcg)
 	 */
 	memcg_reparent_list_lrus(memcg, parent);
 }
-#else
-static int memcg_online_kmem(struct mem_cgroup *memcg)
-{
-	return 0;
-}
-static void memcg_offline_kmem(struct mem_cgroup *memcg)
-{
-}
-#endif /* CONFIG_MEMCG_KMEM */
-
-static int memcg_update_tcp_max(struct mem_cgroup *memcg, unsigned long max)
-{
-	int ret;
-
-	mutex_lock(&memcg_max_mutex);
-
-	ret = page_counter_set_max(&memcg->tcpmem, max);
-	if (ret)
-		goto out;
-
-	if (!memcg->tcpmem_active) {
-		/*
-		 * The active flag needs to be written after the static_key
-		 * update. This is what guarantees that the socket activation
-		 * function is the last one to run. See mem_cgroup_sk_alloc()
-		 * for details, and note that we don't mark any socket as
-		 * belonging to this memcg until that flag is up.
-		 *
-		 * We need to do this, because static_keys will span multiple
-		 * sites, but we can't control their order. If we mark a socket
-		 * as accounted, but the accounting functions are not patched in
-		 * yet, we'll lose accounting.
-		 *
-		 * We never race with the readers in mem_cgroup_sk_alloc(),
-		 * because when this value change, the code to process it is not
-		 * patched in yet.
-		 */
-		static_branch_inc(&memcg_sockets_enabled_key);
-		memcg->tcpmem_active = true;
-	}
-out:
-	mutex_unlock(&memcg_max_mutex);
-	return ret;
-}
-
-/*
- * The user of this function is...
- * RES_LIMIT.
- */
-static ssize_t mem_cgroup_write(struct kernfs_open_file *of,
-				char *buf, size_t nbytes, loff_t off)
-{
-	struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
-	unsigned long nr_pages;
-	int ret;
-
-	buf = strstrip(buf);
-	ret = page_counter_memparse(buf, "-1", &nr_pages);
-	if (ret)
-		return ret;
-
-	switch (MEMFILE_ATTR(of_cft(of)->private)) {
-	case RES_LIMIT:
-		if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */
-			ret = -EINVAL;
-			break;
-		}
-		switch (MEMFILE_TYPE(of_cft(of)->private)) {
-		case _MEM:
-			ret = mem_cgroup_resize_max(memcg, nr_pages, false);
-			break;
-		case _MEMSWAP:
-			ret = mem_cgroup_resize_max(memcg, nr_pages, true);
-			break;
-		case _KMEM:
-			pr_warn_once("kmem.limit_in_bytes is deprecated and will be removed. "
-				     "Writing any value to this file has no effect. "
-				     "Please report your usecase to linux-mm@kvack.org if you "
-				     "depend on this functionality.\n");
-			ret = 0;
-			break;
-		case _TCP:
-			ret = memcg_update_tcp_max(memcg, nr_pages);
-			break;
-		}
-		break;
-	case RES_SOFT_LIMIT:
-		if (IS_ENABLED(CONFIG_PREEMPT_RT)) {
-			ret = -EOPNOTSUPP;
-		} else {
-			WRITE_ONCE(memcg->soft_limit, nr_pages);
-			ret = 0;
-		}
-		break;
-	}
-	return ret ?: nbytes;
-}
-
-static ssize_t mem_cgroup_reset(struct kernfs_open_file *of, char *buf,
-				size_t nbytes, loff_t off)
-{
-	struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
-	struct page_counter *counter;
-
-	switch (MEMFILE_TYPE(of_cft(of)->private)) {
-	case _MEM:
-		counter = &memcg->memory;
-		break;
-	case _MEMSWAP:
-		counter = &memcg->memsw;
-		break;
-	case _KMEM:
-		counter = &memcg->kmem;
-		break;
-	case _TCP:
-		counter = &memcg->tcpmem;
-		break;
-	default:
-		BUG();
-	}
-
-	switch (MEMFILE_ATTR(of_cft(of)->private)) {
-	case RES_MAX_USAGE:
-		page_counter_reset_watermark(counter);
-		break;
-	case RES_FAILCNT:
-		counter->failcnt = 0;
-		break;
-	default:
-		BUG();
-	}
-
-	return nbytes;
-}
-
-static u64 mem_cgroup_move_charge_read(struct cgroup_subsys_state *css,
-					struct cftype *cft)
-{
-	return mem_cgroup_from_css(css)->move_charge_at_immigrate;
-}
-
-#ifdef CONFIG_MMU
-static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css,
-					struct cftype *cft, u64 val)
-{
-	struct mem_cgroup *memcg = mem_cgroup_from_css(css);
-
-	pr_warn_once("Cgroup memory moving (move_charge_at_immigrate) is deprecated. "
-		     "Please report your usecase to linux-mm@kvack.org if you "
-		     "depend on this functionality.\n");
-
-	if (val & ~MOVE_MASK)
-		return -EINVAL;
-
-	/*
-	 * No kind of locking is needed in here, because ->can_attach() will
-	 * check this value once in the beginning of the process, and then carry
-	 * on with stale data. This means that changes to this value will only
-	 * affect task migrations starting after the change.
-	 */
-	memcg->move_charge_at_immigrate = val;
-	return 0;
-}
-#else
-static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css,
-					struct cftype *cft, u64 val)
-{
-	return -ENOSYS;
-}
-#endif
-
-#ifdef CONFIG_NUMA
-
-#define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE))
-#define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON))
-#define LRU_ALL	     ((1 << NR_LRU_LISTS) - 1)
-
-static unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg,
-				int nid, unsigned int lru_mask, bool tree)
-{
-	struct lruvec *lruvec = mem_cgroup_lruvec(memcg, NODE_DATA(nid));
-	unsigned long nr = 0;
-	enum lru_list lru;
-
-	VM_BUG_ON((unsigned)nid >= nr_node_ids);
-
-	for_each_lru(lru) {
-		if (!(BIT(lru) & lru_mask))
-			continue;
-		if (tree)
-			nr += lruvec_page_state(lruvec, NR_LRU_BASE + lru);
-		else
-			nr += lruvec_page_state_local(lruvec, NR_LRU_BASE + lru);
-	}
-	return nr;
-}
-
-static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg,
-					     unsigned int lru_mask,
-					     bool tree)
-{
-	unsigned long nr = 0;
-	enum lru_list lru;
-
-	for_each_lru(lru) {
-		if (!(BIT(lru) & lru_mask))
-			continue;
-		if (tree)
-			nr += memcg_page_state(memcg, NR_LRU_BASE + lru);
-		else
-			nr += memcg_page_state_local(memcg, NR_LRU_BASE + lru);
-	}
-	return nr;
-}
-
-static int memcg_numa_stat_show(struct seq_file *m, void *v)
-{
-	struct numa_stat {
-		const char *name;
-		unsigned int lru_mask;
-	};
-
-	static const struct numa_stat stats[] = {
-		{ "total", LRU_ALL },
-		{ "file", LRU_ALL_FILE },
-		{ "anon", LRU_ALL_ANON },
-		{ "unevictable", BIT(LRU_UNEVICTABLE) },
-	};
-	const struct numa_stat *stat;
-	int nid;
-	struct mem_cgroup *memcg = mem_cgroup_from_seq(m);
-
-	mem_cgroup_flush_stats(memcg);
-
-	for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) {
-		seq_printf(m, "%s=%lu", stat->name,
-			   mem_cgroup_nr_lru_pages(memcg, stat->lru_mask,
-						   false));
-		for_each_node_state(nid, N_MEMORY)
-			seq_printf(m, " N%d=%lu", nid,
-				   mem_cgroup_node_nr_lru_pages(memcg, nid,
-							stat->lru_mask, false));
-		seq_putc(m, '\n');
-	}
-
-	for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) {
-
-		seq_printf(m, "hierarchical_%s=%lu", stat->name,
-			   mem_cgroup_nr_lru_pages(memcg, stat->lru_mask,
-						   true));
-		for_each_node_state(nid, N_MEMORY)
-			seq_printf(m, " N%d=%lu", nid,
-				   mem_cgroup_node_nr_lru_pages(memcg, nid,
-							stat->lru_mask, true));
-		seq_putc(m, '\n');
-	}
-
-	return 0;
-}
-#endif /* CONFIG_NUMA */
-
-static const unsigned int memcg1_stats[] = {
-	NR_FILE_PAGES,
-	NR_ANON_MAPPED,
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	NR_ANON_THPS,
-#endif
-	NR_SHMEM,
-	NR_FILE_MAPPED,
-	NR_FILE_DIRTY,
-	NR_WRITEBACK,
-	WORKINGSET_REFAULT_ANON,
-	WORKINGSET_REFAULT_FILE,
-#ifdef CONFIG_SWAP
-	MEMCG_SWAP,
-	NR_SWAPCACHE,
-#endif
-};
-
-static const char *const memcg1_stat_names[] = {
-	"cache",
-	"rss",
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	"rss_huge",
-#endif
-	"shmem",
-	"mapped_file",
-	"dirty",
-	"writeback",
-	"workingset_refault_anon",
-	"workingset_refault_file",
-#ifdef CONFIG_SWAP
-	"swap",
-	"swapcached",
-#endif
-};
-
-/* Universal VM events cgroup1 shows, original sort order */
-static const unsigned int memcg1_events[] = {
-	PGPGIN,
-	PGPGOUT,
-	PGFAULT,
-	PGMAJFAULT,
-};
-
-static void memcg1_stat_format(struct mem_cgroup *memcg, struct seq_buf *s)
-{
-	unsigned long memory, memsw;
-	struct mem_cgroup *mi;
-	unsigned int i;
-
-	BUILD_BUG_ON(ARRAY_SIZE(memcg1_stat_names) != ARRAY_SIZE(memcg1_stats));
-
-	mem_cgroup_flush_stats(memcg);
-
-	for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) {
-		unsigned long nr;
-
-		nr = memcg_page_state_local_output(memcg, memcg1_stats[i]);
-		seq_buf_printf(s, "%s %lu\n", memcg1_stat_names[i], nr);
-	}
-
-	for (i = 0; i < ARRAY_SIZE(memcg1_events); i++)
-		seq_buf_printf(s, "%s %lu\n", vm_event_name(memcg1_events[i]),
-			       memcg_events_local(memcg, memcg1_events[i]));
-
-	for (i = 0; i < NR_LRU_LISTS; i++)
-		seq_buf_printf(s, "%s %lu\n", lru_list_name(i),
-			       memcg_page_state_local(memcg, NR_LRU_BASE + i) *
-			       PAGE_SIZE);
-
-	/* Hierarchical information */
-	memory = memsw = PAGE_COUNTER_MAX;
-	for (mi = memcg; mi; mi = parent_mem_cgroup(mi)) {
-		memory = min(memory, READ_ONCE(mi->memory.max));
-		memsw = min(memsw, READ_ONCE(mi->memsw.max));
-	}
-	seq_buf_printf(s, "hierarchical_memory_limit %llu\n",
-		       (u64)memory * PAGE_SIZE);
-	seq_buf_printf(s, "hierarchical_memsw_limit %llu\n",
-		       (u64)memsw * PAGE_SIZE);
-
-	for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) {
-		unsigned long nr;
-
-		nr = memcg_page_state_output(memcg, memcg1_stats[i]);
-		seq_buf_printf(s, "total_%s %llu\n", memcg1_stat_names[i],
-			       (u64)nr);
-	}
-
-	for (i = 0; i < ARRAY_SIZE(memcg1_events); i++)
-		seq_buf_printf(s, "total_%s %llu\n",
-			       vm_event_name(memcg1_events[i]),
-			       (u64)memcg_events(memcg, memcg1_events[i]));
-
-	for (i = 0; i < NR_LRU_LISTS; i++)
-		seq_buf_printf(s, "total_%s %llu\n", lru_list_name(i),
-			       (u64)memcg_page_state(memcg, NR_LRU_BASE + i) *
-			       PAGE_SIZE);
-
-#ifdef CONFIG_DEBUG_VM
-	{
-		pg_data_t *pgdat;
-		struct mem_cgroup_per_node *mz;
-		unsigned long anon_cost = 0;
-		unsigned long file_cost = 0;
-
-		for_each_online_pgdat(pgdat) {
-			mz = memcg->nodeinfo[pgdat->node_id];
-
-			anon_cost += mz->lruvec.anon_cost;
-			file_cost += mz->lruvec.file_cost;
-		}
-		seq_buf_printf(s, "anon_cost %lu\n", anon_cost);
-		seq_buf_printf(s, "file_cost %lu\n", file_cost);
-	}
-#endif
-}
-
-static u64 mem_cgroup_swappiness_read(struct cgroup_subsys_state *css,
-				      struct cftype *cft)
-{
-	struct mem_cgroup *memcg = mem_cgroup_from_css(css);
-
-	return mem_cgroup_swappiness(memcg);
-}
-
-static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css,
-				       struct cftype *cft, u64 val)
-{
-	struct mem_cgroup *memcg = mem_cgroup_from_css(css);
-
-	if (val > 200)
-		return -EINVAL;
-
-	if (!mem_cgroup_is_root(memcg))
-		WRITE_ONCE(memcg->swappiness, val);
-	else
-		WRITE_ONCE(vm_swappiness, val);
-
-	return 0;
-}
-
-static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap)
-{
-	struct mem_cgroup_threshold_ary *t;
-	unsigned long usage;
-	int i;
-
-	rcu_read_lock();
-	if (!swap)
-		t = rcu_dereference(memcg->thresholds.primary);
-	else
-		t = rcu_dereference(memcg->memsw_thresholds.primary);
-
-	if (!t)
-		goto unlock;
-
-	usage = mem_cgroup_usage(memcg, swap);
-
-	/*
-	 * current_threshold points to threshold just below or equal to usage.
-	 * If it's not true, a threshold was crossed after last
-	 * call of __mem_cgroup_threshold().
-	 */
-	i = t->current_threshold;
-
-	/*
-	 * Iterate backward over array of thresholds starting from
-	 * current_threshold and check if a threshold is crossed.
-	 * If none of thresholds below usage is crossed, we read
-	 * only one element of the array here.
-	 */
-	for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--)
-		eventfd_signal(t->entries[i].eventfd);
-
-	/* i = current_threshold + 1 */
-	i++;
-
-	/*
-	 * Iterate forward over array of thresholds starting from
-	 * current_threshold+1 and check if a threshold is crossed.
-	 * If none of thresholds above usage is crossed, we read
-	 * only one element of the array here.
-	 */
-	for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++)
-		eventfd_signal(t->entries[i].eventfd);
-
-	/* Update current_threshold */
-	t->current_threshold = i - 1;
-unlock:
-	rcu_read_unlock();
-}
-
-static void mem_cgroup_threshold(struct mem_cgroup *memcg)
-{
-	while (memcg) {
-		__mem_cgroup_threshold(memcg, false);
-		if (do_memsw_account())
-			__mem_cgroup_threshold(memcg, true);
-
-		memcg = parent_mem_cgroup(memcg);
-	}
-}
-
-static int compare_thresholds(const void *a, const void *b)
-{
-	const struct mem_cgroup_threshold *_a = a;
-	const struct mem_cgroup_threshold *_b = b;
-
-	if (_a->threshold > _b->threshold)
-		return 1;
-
-	if (_a->threshold < _b->threshold)
-		return -1;
-
-	return 0;
-}
-
-static int mem_cgroup_oom_notify_cb(struct mem_cgroup *memcg)
-{
-	struct mem_cgroup_eventfd_list *ev;
-
-	spin_lock(&memcg_oom_lock);
-
-	list_for_each_entry(ev, &memcg->oom_notify, list)
-		eventfd_signal(ev->eventfd);
-
-	spin_unlock(&memcg_oom_lock);
-	return 0;
-}
-
-static void mem_cgroup_oom_notify(struct mem_cgroup *memcg)
-{
-	struct mem_cgroup *iter;
-
-	for_each_mem_cgroup_tree(iter, memcg)
-		mem_cgroup_oom_notify_cb(iter);
-}
-
-static int __mem_cgroup_usage_register_event(struct mem_cgroup *memcg,
-	struct eventfd_ctx *eventfd, const char *args, enum res_type type)
-{
-	struct mem_cgroup_thresholds *thresholds;
-	struct mem_cgroup_threshold_ary *new;
-	unsigned long threshold;
-	unsigned long usage;
-	int i, size, ret;
-
-	ret = page_counter_memparse(args, "-1", &threshold);
-	if (ret)
-		return ret;
-
-	mutex_lock(&memcg->thresholds_lock);
-
-	if (type == _MEM) {
-		thresholds = &memcg->thresholds;
-		usage = mem_cgroup_usage(memcg, false);
-	} else if (type == _MEMSWAP) {
-		thresholds = &memcg->memsw_thresholds;
-		usage = mem_cgroup_usage(memcg, true);
-	} else
-		BUG();
-
-	/* Check if a threshold crossed before adding a new one */
-	if (thresholds->primary)
-		__mem_cgroup_threshold(memcg, type == _MEMSWAP);
-
-	size = thresholds->primary ? thresholds->primary->size + 1 : 1;
-
-	/* Allocate memory for new array of thresholds */
-	new = kmalloc(struct_size(new, entries, size), GFP_KERNEL);
-	if (!new) {
-		ret = -ENOMEM;
-		goto unlock;
-	}
-	new->size = size;
-
-	/* Copy thresholds (if any) to new array */
-	if (thresholds->primary)
-		memcpy(new->entries, thresholds->primary->entries,
-		       flex_array_size(new, entries, size - 1));
-
-	/* Add new threshold */
-	new->entries[size - 1].eventfd = eventfd;
-	new->entries[size - 1].threshold = threshold;
-
-	/* Sort thresholds. Registering of new threshold isn't time-critical */
-	sort(new->entries, size, sizeof(*new->entries),
-			compare_thresholds, NULL);
-
-	/* Find current threshold */
-	new->current_threshold = -1;
-	for (i = 0; i < size; i++) {
-		if (new->entries[i].threshold <= usage) {
-			/*
-			 * new->current_threshold will not be used until
-			 * rcu_assign_pointer(), so it's safe to increment
-			 * it here.
-			 */
-			++new->current_threshold;
-		} else
-			break;
-	}
-
-	/* Free old spare buffer and save old primary buffer as spare */
-	kfree(thresholds->spare);
-	thresholds->spare = thresholds->primary;
-
-	rcu_assign_pointer(thresholds->primary, new);
-
-	/* To be sure that nobody uses thresholds */
-	synchronize_rcu();
-
-unlock:
-	mutex_unlock(&memcg->thresholds_lock);
-
-	return ret;
-}
-
-static int mem_cgroup_usage_register_event(struct mem_cgroup *memcg,
-	struct eventfd_ctx *eventfd, const char *args)
-{
-	return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEM);
-}
-
-static int memsw_cgroup_usage_register_event(struct mem_cgroup *memcg,
-	struct eventfd_ctx *eventfd, const char *args)
-{
-	return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEMSWAP);
-}
-
-static void __mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg,
-	struct eventfd_ctx *eventfd, enum res_type type)
-{
-	struct mem_cgroup_thresholds *thresholds;
-	struct mem_cgroup_threshold_ary *new;
-	unsigned long usage;
-	int i, j, size, entries;
-
-	mutex_lock(&memcg->thresholds_lock);
-
-	if (type == _MEM) {
-		thresholds = &memcg->thresholds;
-		usage = mem_cgroup_usage(memcg, false);
-	} else if (type == _MEMSWAP) {
-		thresholds = &memcg->memsw_thresholds;
-		usage = mem_cgroup_usage(memcg, true);
-	} else
-		BUG();
-
-	if (!thresholds->primary)
-		goto unlock;
-
-	/* Check if a threshold crossed before removing */
-	__mem_cgroup_threshold(memcg, type == _MEMSWAP);
-
-	/* Calculate new number of threshold */
-	size = entries = 0;
-	for (i = 0; i < thresholds->primary->size; i++) {
-		if (thresholds->primary->entries[i].eventfd != eventfd)
-			size++;
-		else
-			entries++;
-	}
-
-	new = thresholds->spare;
-
-	/* If no items related to eventfd have been cleared, nothing to do */
-	if (!entries)
-		goto unlock;
-
-	/* Set thresholds array to NULL if we don't have thresholds */
-	if (!size) {
-		kfree(new);
-		new = NULL;
-		goto swap_buffers;
-	}
-
-	new->size = size;
-
-	/* Copy thresholds and find current threshold */
-	new->current_threshold = -1;
-	for (i = 0, j = 0; i < thresholds->primary->size; i++) {
-		if (thresholds->primary->entries[i].eventfd == eventfd)
-			continue;
-
-		new->entries[j] = thresholds->primary->entries[i];
-		if (new->entries[j].threshold <= usage) {
-			/*
-			 * new->current_threshold will not be used
-			 * until rcu_assign_pointer(), so it's safe to increment
-			 * it here.
-			 */
-			++new->current_threshold;
-		}
-		j++;
-	}
-
-swap_buffers:
-	/* Swap primary and spare array */
-	thresholds->spare = thresholds->primary;
-
-	rcu_assign_pointer(thresholds->primary, new);
-
-	/* To be sure that nobody uses thresholds */
-	synchronize_rcu();
-
-	/* If all events are unregistered, free the spare array */
-	if (!new) {
-		kfree(thresholds->spare);
-		thresholds->spare = NULL;
-	}
-unlock:
-	mutex_unlock(&memcg->thresholds_lock);
-}
-
-static void mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg,
-	struct eventfd_ctx *eventfd)
-{
-	return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEM);
-}
-
-static void memsw_cgroup_usage_unregister_event(struct mem_cgroup *memcg,
-	struct eventfd_ctx *eventfd)
-{
-	return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEMSWAP);
-}
-
-static int mem_cgroup_oom_register_event(struct mem_cgroup *memcg,
-	struct eventfd_ctx *eventfd, const char *args)
-{
-	struct mem_cgroup_eventfd_list *event;
-
-	event = kmalloc(sizeof(*event),	GFP_KERNEL);
-	if (!event)
-		return -ENOMEM;
-
-	spin_lock(&memcg_oom_lock);
-
-	event->eventfd = eventfd;
-	list_add(&event->list, &memcg->oom_notify);
-
-	/* already in OOM ? */
-	if (memcg->under_oom)
-		eventfd_signal(eventfd);
-	spin_unlock(&memcg_oom_lock);
-
-	return 0;
-}
-
-static void mem_cgroup_oom_unregister_event(struct mem_cgroup *memcg,
-	struct eventfd_ctx *eventfd)
-{
-	struct mem_cgroup_eventfd_list *ev, *tmp;
-
-	spin_lock(&memcg_oom_lock);
-
-	list_for_each_entry_safe(ev, tmp, &memcg->oom_notify, list) {
-		if (ev->eventfd == eventfd) {
-			list_del(&ev->list);
-			kfree(ev);
-		}
-	}
-
-	spin_unlock(&memcg_oom_lock);
-}
-
-static int mem_cgroup_oom_control_read(struct seq_file *sf, void *v)
-{
-	struct mem_cgroup *memcg = mem_cgroup_from_seq(sf);
-
-	seq_printf(sf, "oom_kill_disable %d\n", READ_ONCE(memcg->oom_kill_disable));
-	seq_printf(sf, "under_oom %d\n", (bool)memcg->under_oom);
-	seq_printf(sf, "oom_kill %lu\n",
-		   atomic_long_read(&memcg->memory_events[MEMCG_OOM_KILL]));
-	return 0;
-}
-
-static int mem_cgroup_oom_control_write(struct cgroup_subsys_state *css,
-	struct cftype *cft, u64 val)
-{
-	struct mem_cgroup *memcg = mem_cgroup_from_css(css);
-
-	/* cannot set to root cgroup and only 0 and 1 are allowed */
-	if (mem_cgroup_is_root(memcg) || !((val == 0) || (val == 1)))
-		return -EINVAL;
-
-	WRITE_ONCE(memcg->oom_kill_disable, val);
-	if (!val)
-		memcg_oom_recover(memcg);
-
-	return 0;
-}
 
 #ifdef CONFIG_CGROUP_WRITEBACK
 
@@ -5165,384 +3361,6 @@ static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg)
 #endif	/* CONFIG_CGROUP_WRITEBACK */
 
 /*
- * DO NOT USE IN NEW FILES.
- *
- * "cgroup.event_control" implementation.
- *
- * This is way over-engineered.  It tries to support fully configurable
- * events for each user.  Such level of flexibility is completely
- * unnecessary especially in the light of the planned unified hierarchy.
- *
- * Please deprecate this and replace with something simpler if at all
- * possible.
- */
-
-/*
- * Unregister event and free resources.
- *
- * Gets called from workqueue.
- */
-static void memcg_event_remove(struct work_struct *work)
-{
-	struct mem_cgroup_event *event =
-		container_of(work, struct mem_cgroup_event, remove);
-	struct mem_cgroup *memcg = event->memcg;
-
-	remove_wait_queue(event->wqh, &event->wait);
-
-	event->unregister_event(memcg, event->eventfd);
-
-	/* Notify userspace the event is going away. */
-	eventfd_signal(event->eventfd);
-
-	eventfd_ctx_put(event->eventfd);
-	kfree(event);
-	css_put(&memcg->css);
-}
-
-/*
- * Gets called on EPOLLHUP on eventfd when user closes it.
- *
- * Called with wqh->lock held and interrupts disabled.
- */
-static int memcg_event_wake(wait_queue_entry_t *wait, unsigned mode,
-			    int sync, void *key)
-{
-	struct mem_cgroup_event *event =
-		container_of(wait, struct mem_cgroup_event, wait);
-	struct mem_cgroup *memcg = event->memcg;
-	__poll_t flags = key_to_poll(key);
-
-	if (flags & EPOLLHUP) {
-		/*
-		 * If the event has been detached at cgroup removal, we
-		 * can simply return knowing the other side will cleanup
-		 * for us.
-		 *
-		 * We can't race against event freeing since the other
-		 * side will require wqh->lock via remove_wait_queue(),
-		 * which we hold.
-		 */
-		spin_lock(&memcg->event_list_lock);
-		if (!list_empty(&event->list)) {
-			list_del_init(&event->list);
-			/*
-			 * We are in atomic context, but cgroup_event_remove()
-			 * may sleep, so we have to call it in workqueue.
-			 */
-			schedule_work(&event->remove);
-		}
-		spin_unlock(&memcg->event_list_lock);
-	}
-
-	return 0;
-}
-
-static void memcg_event_ptable_queue_proc(struct file *file,
-		wait_queue_head_t *wqh, poll_table *pt)
-{
-	struct mem_cgroup_event *event =
-		container_of(pt, struct mem_cgroup_event, pt);
-
-	event->wqh = wqh;
-	add_wait_queue(wqh, &event->wait);
-}
-
-/*
- * DO NOT USE IN NEW FILES.
- *
- * Parse input and register new cgroup event handler.
- *
- * Input must be in format '<event_fd> <control_fd> <args>'.
- * Interpretation of args is defined by control file implementation.
- */
-static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
-					 char *buf, size_t nbytes, loff_t off)
-{
-	struct cgroup_subsys_state *css = of_css(of);
-	struct mem_cgroup *memcg = mem_cgroup_from_css(css);
-	struct mem_cgroup_event *event;
-	struct cgroup_subsys_state *cfile_css;
-	unsigned int efd, cfd;
-	struct fd efile;
-	struct fd cfile;
-	struct dentry *cdentry;
-	const char *name;
-	char *endp;
-	int ret;
-
-	if (IS_ENABLED(CONFIG_PREEMPT_RT))
-		return -EOPNOTSUPP;
-
-	buf = strstrip(buf);
-
-	efd = simple_strtoul(buf, &endp, 10);
-	if (*endp != ' ')
-		return -EINVAL;
-	buf = endp + 1;
-
-	cfd = simple_strtoul(buf, &endp, 10);
-	if ((*endp != ' ') && (*endp != '\0'))
-		return -EINVAL;
-	buf = endp + 1;
-
-	event = kzalloc(sizeof(*event), GFP_KERNEL);
-	if (!event)
-		return -ENOMEM;
-
-	event->memcg = memcg;
-	INIT_LIST_HEAD(&event->list);
-	init_poll_funcptr(&event->pt, memcg_event_ptable_queue_proc);
-	init_waitqueue_func_entry(&event->wait, memcg_event_wake);
-	INIT_WORK(&event->remove, memcg_event_remove);
-
-	efile = fdget(efd);
-	if (!efile.file) {
-		ret = -EBADF;
-		goto out_kfree;
-	}
-
-	event->eventfd = eventfd_ctx_fileget(efile.file);
-	if (IS_ERR(event->eventfd)) {
-		ret = PTR_ERR(event->eventfd);
-		goto out_put_efile;
-	}
-
-	cfile = fdget(cfd);
-	if (!cfile.file) {
-		ret = -EBADF;
-		goto out_put_eventfd;
-	}
-
-	/* the process need read permission on control file */
-	/* AV: shouldn't we check that it's been opened for read instead? */
-	ret = file_permission(cfile.file, MAY_READ);
-	if (ret < 0)
-		goto out_put_cfile;
-
-	/*
-	 * The control file must be a regular cgroup1 file. As a regular cgroup
-	 * file can't be renamed, it's safe to access its name afterwards.
-	 */
-	cdentry = cfile.file->f_path.dentry;
-	if (cdentry->d_sb->s_type != &cgroup_fs_type || !d_is_reg(cdentry)) {
-		ret = -EINVAL;
-		goto out_put_cfile;
-	}
-
-	/*
-	 * Determine the event callbacks and set them in @event.  This used
-	 * to be done via struct cftype but cgroup core no longer knows
-	 * about these events.  The following is crude but the whole thing
-	 * is for compatibility anyway.
-	 *
-	 * DO NOT ADD NEW FILES.
-	 */
-	name = cdentry->d_name.name;
-
-	if (!strcmp(name, "memory.usage_in_bytes")) {
-		event->register_event = mem_cgroup_usage_register_event;
-		event->unregister_event = mem_cgroup_usage_unregister_event;
-	} else if (!strcmp(name, "memory.oom_control")) {
-		event->register_event = mem_cgroup_oom_register_event;
-		event->unregister_event = mem_cgroup_oom_unregister_event;
-	} else if (!strcmp(name, "memory.pressure_level")) {
-		event->register_event = vmpressure_register_event;
-		event->unregister_event = vmpressure_unregister_event;
-	} else if (!strcmp(name, "memory.memsw.usage_in_bytes")) {
-		event->register_event = memsw_cgroup_usage_register_event;
-		event->unregister_event = memsw_cgroup_usage_unregister_event;
-	} else {
-		ret = -EINVAL;
-		goto out_put_cfile;
-	}
-
-	/*
-	 * Verify @cfile should belong to @css.  Also, remaining events are
-	 * automatically removed on cgroup destruction but the removal is
-	 * asynchronous, so take an extra ref on @css.
-	 */
-	cfile_css = css_tryget_online_from_dir(cdentry->d_parent,
-					       &memory_cgrp_subsys);
-	ret = -EINVAL;
-	if (IS_ERR(cfile_css))
-		goto out_put_cfile;
-	if (cfile_css != css) {
-		css_put(cfile_css);
-		goto out_put_cfile;
-	}
-
-	ret = event->register_event(memcg, event->eventfd, buf);
-	if (ret)
-		goto out_put_css;
-
-	vfs_poll(efile.file, &event->pt);
-
-	spin_lock_irq(&memcg->event_list_lock);
-	list_add(&event->list, &memcg->event_list);
-	spin_unlock_irq(&memcg->event_list_lock);
-
-	fdput(cfile);
-	fdput(efile);
-
-	return nbytes;
-
-out_put_css:
-	css_put(css);
-out_put_cfile:
-	fdput(cfile);
-out_put_eventfd:
-	eventfd_ctx_put(event->eventfd);
-out_put_efile:
-	fdput(efile);
-out_kfree:
-	kfree(event);
-
-	return ret;
-}
-
-#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_SLUB_DEBUG)
-static int mem_cgroup_slab_show(struct seq_file *m, void *p)
-{
-	/*
-	 * Deprecated.
-	 * Please, take a look at tools/cgroup/memcg_slabinfo.py .
-	 */
-	return 0;
-}
-#endif
-
-static int memory_stat_show(struct seq_file *m, void *v);
-
-static struct cftype mem_cgroup_legacy_files[] = {
-	{
-		.name = "usage_in_bytes",
-		.private = MEMFILE_PRIVATE(_MEM, RES_USAGE),
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{
-		.name = "max_usage_in_bytes",
-		.private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE),
-		.write = mem_cgroup_reset,
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{
-		.name = "limit_in_bytes",
-		.private = MEMFILE_PRIVATE(_MEM, RES_LIMIT),
-		.write = mem_cgroup_write,
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{
-		.name = "soft_limit_in_bytes",
-		.private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT),
-		.write = mem_cgroup_write,
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{
-		.name = "failcnt",
-		.private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT),
-		.write = mem_cgroup_reset,
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{
-		.name = "stat",
-		.seq_show = memory_stat_show,
-	},
-	{
-		.name = "force_empty",
-		.write = mem_cgroup_force_empty_write,
-	},
-	{
-		.name = "use_hierarchy",
-		.write_u64 = mem_cgroup_hierarchy_write,
-		.read_u64 = mem_cgroup_hierarchy_read,
-	},
-	{
-		.name = "cgroup.event_control",		/* XXX: for compat */
-		.write = memcg_write_event_control,
-		.flags = CFTYPE_NO_PREFIX | CFTYPE_WORLD_WRITABLE,
-	},
-	{
-		.name = "swappiness",
-		.read_u64 = mem_cgroup_swappiness_read,
-		.write_u64 = mem_cgroup_swappiness_write,
-	},
-	{
-		.name = "move_charge_at_immigrate",
-		.read_u64 = mem_cgroup_move_charge_read,
-		.write_u64 = mem_cgroup_move_charge_write,
-	},
-	{
-		.name = "oom_control",
-		.seq_show = mem_cgroup_oom_control_read,
-		.write_u64 = mem_cgroup_oom_control_write,
-	},
-	{
-		.name = "pressure_level",
-		.seq_show = mem_cgroup_dummy_seq_show,
-	},
-#ifdef CONFIG_NUMA
-	{
-		.name = "numa_stat",
-		.seq_show = memcg_numa_stat_show,
-	},
-#endif
-	{
-		.name = "kmem.limit_in_bytes",
-		.private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT),
-		.write = mem_cgroup_write,
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{
-		.name = "kmem.usage_in_bytes",
-		.private = MEMFILE_PRIVATE(_KMEM, RES_USAGE),
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{
-		.name = "kmem.failcnt",
-		.private = MEMFILE_PRIVATE(_KMEM, RES_FAILCNT),
-		.write = mem_cgroup_reset,
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{
-		.name = "kmem.max_usage_in_bytes",
-		.private = MEMFILE_PRIVATE(_KMEM, RES_MAX_USAGE),
-		.write = mem_cgroup_reset,
-		.read_u64 = mem_cgroup_read_u64,
-	},
-#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_SLUB_DEBUG)
-	{
-		.name = "kmem.slabinfo",
-		.seq_show = mem_cgroup_slab_show,
-	},
-#endif
-	{
-		.name = "kmem.tcp.limit_in_bytes",
-		.private = MEMFILE_PRIVATE(_TCP, RES_LIMIT),
-		.write = mem_cgroup_write,
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{
-		.name = "kmem.tcp.usage_in_bytes",
-		.private = MEMFILE_PRIVATE(_TCP, RES_USAGE),
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{
-		.name = "kmem.tcp.failcnt",
-		.private = MEMFILE_PRIVATE(_TCP, RES_FAILCNT),
-		.write = mem_cgroup_reset,
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{
-		.name = "kmem.tcp.max_usage_in_bytes",
-		.private = MEMFILE_PRIVATE(_TCP, RES_MAX_USAGE),
-		.write = mem_cgroup_reset,
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{ },	/* terminate */
-};
-
-/*
  * Private memory cgroup IDR
  *
  * Swap-out records and page cache shadow entries need to store memcg
@@ -5577,13 +3395,13 @@ static void mem_cgroup_id_remove(struct mem_cgroup *memcg)
 	}
 }
 
-static void __maybe_unused mem_cgroup_id_get_many(struct mem_cgroup *memcg,
-						  unsigned int n)
+void __maybe_unused mem_cgroup_id_get_many(struct mem_cgroup *memcg,
+					   unsigned int n)
 {
 	refcount_add(n, &memcg->id.ref);
 }
 
-static void mem_cgroup_id_put_many(struct mem_cgroup *memcg, unsigned int n)
+void mem_cgroup_id_put_many(struct mem_cgroup *memcg, unsigned int n)
 {
 	if (refcount_sub_and_test(n, &memcg->id.ref)) {
 		mem_cgroup_id_remove(memcg);
@@ -5739,17 +3557,11 @@ static struct mem_cgroup *mem_cgroup_alloc(struct mem_cgroup *parent)
 		goto fail;
 
 	INIT_WORK(&memcg->high_work, high_work_func);
-	INIT_LIST_HEAD(&memcg->oom_notify);
-	mutex_init(&memcg->thresholds_lock);
-	spin_lock_init(&memcg->move_lock);
 	vmpressure_init(&memcg->vmpressure);
-	INIT_LIST_HEAD(&memcg->event_list);
-	spin_lock_init(&memcg->event_list_lock);
 	memcg->socket_pressure = jiffies;
-#ifdef CONFIG_MEMCG_KMEM
+	memcg1_memcg_init(memcg);
 	memcg->kmemcg_id = -1;
 	INIT_LIST_HEAD(&memcg->objcg_list);
-#endif
 #ifdef CONFIG_CGROUP_WRITEBACK
 	INIT_LIST_HEAD(&memcg->cgwb_list);
 	for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++)
@@ -5782,8 +3594,8 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css)
 		return ERR_CAST(memcg);
 
 	page_counter_set_high(&memcg->memory, PAGE_COUNTER_MAX);
-	WRITE_ONCE(memcg->soft_limit, PAGE_COUNTER_MAX);
-#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP)
+	memcg1_soft_limit_reset(memcg);
+#ifdef CONFIG_ZSWAP
 	memcg->zswap_max = PAGE_COUNTER_MAX;
 	WRITE_ONCE(memcg->zswap_writeback,
 		!parent || READ_ONCE(parent->zswap_writeback));
@@ -5791,20 +3603,23 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css)
 	page_counter_set_high(&memcg->swap, PAGE_COUNTER_MAX);
 	if (parent) {
 		WRITE_ONCE(memcg->swappiness, mem_cgroup_swappiness(parent));
-		WRITE_ONCE(memcg->oom_kill_disable, READ_ONCE(parent->oom_kill_disable));
 
 		page_counter_init(&memcg->memory, &parent->memory);
 		page_counter_init(&memcg->swap, &parent->swap);
+#ifdef CONFIG_MEMCG_V1
+		WRITE_ONCE(memcg->oom_kill_disable, READ_ONCE(parent->oom_kill_disable));
 		page_counter_init(&memcg->kmem, &parent->kmem);
 		page_counter_init(&memcg->tcpmem, &parent->tcpmem);
+#endif
 	} else {
 		init_memcg_stats();
 		init_memcg_events();
 		page_counter_init(&memcg->memory, NULL);
 		page_counter_init(&memcg->swap, NULL);
+#ifdef CONFIG_MEMCG_V1
 		page_counter_init(&memcg->kmem, NULL);
 		page_counter_init(&memcg->tcpmem, NULL);
-
+#endif
 		root_mem_cgroup = memcg;
 		return &memcg->css;
 	}
@@ -5812,10 +3627,8 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css)
 	if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket)
 		static_branch_inc(&memcg_sockets_enabled_key);
 
-#if defined(CONFIG_MEMCG_KMEM)
 	if (!cgroup_memory_nobpf)
 		static_branch_inc(&memcg_bpf_enabled_key);
-#endif
 
 	return &memcg->css;
 }
@@ -5867,19 +3680,8 @@ remove_id:
 static void mem_cgroup_css_offline(struct cgroup_subsys_state *css)
 {
 	struct mem_cgroup *memcg = mem_cgroup_from_css(css);
-	struct mem_cgroup_event *event, *tmp;
 
-	/*
-	 * Unregister events and notify userspace.
-	 * Notify userspace about cgroup removing only after rmdir of cgroup
-	 * directory to avoid race between userspace and kernelspace.
-	 */
-	spin_lock_irq(&memcg->event_list_lock);
-	list_for_each_entry_safe(event, tmp, &memcg->event_list, list) {
-		list_del_init(&event->list);
-		schedule_work(&event->remove);
-	}
-	spin_unlock_irq(&memcg->event_list_lock);
+	memcg1_css_offline(memcg);
 
 	page_counter_set_min(&memcg->memory, 0);
 	page_counter_set_low(&memcg->memory, 0);
@@ -5916,17 +3718,15 @@ static void mem_cgroup_css_free(struct cgroup_subsys_state *css)
 	if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket)
 		static_branch_dec(&memcg_sockets_enabled_key);
 
-	if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && memcg->tcpmem_active)
+	if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && memcg1_tcpmem_active(memcg))
 		static_branch_dec(&memcg_sockets_enabled_key);
 
-#if defined(CONFIG_MEMCG_KMEM)
 	if (!cgroup_memory_nobpf)
 		static_branch_dec(&memcg_bpf_enabled_key);
-#endif
 
 	vmpressure_cleanup(&memcg->vmpressure);
 	cancel_work_sync(&memcg->high_work);
-	mem_cgroup_remove_from_trees(memcg);
+	memcg1_remove_from_trees(memcg);
 	free_shrinker_info(memcg);
 	mem_cgroup_free(memcg);
 }
@@ -5950,12 +3750,14 @@ static void mem_cgroup_css_reset(struct cgroup_subsys_state *css)
 
 	page_counter_set_max(&memcg->memory, PAGE_COUNTER_MAX);
 	page_counter_set_max(&memcg->swap, PAGE_COUNTER_MAX);
+#ifdef CONFIG_MEMCG_V1
 	page_counter_set_max(&memcg->kmem, PAGE_COUNTER_MAX);
 	page_counter_set_max(&memcg->tcpmem, PAGE_COUNTER_MAX);
+#endif
 	page_counter_set_min(&memcg->memory, 0);
 	page_counter_set_low(&memcg->memory, 0);
 	page_counter_set_high(&memcg->memory, PAGE_COUNTER_MAX);
-	WRITE_ONCE(memcg->soft_limit, PAGE_COUNTER_MAX);
+	memcg1_soft_limit_reset(memcg);
 	page_counter_set_high(&memcg->swap, PAGE_COUNTER_MAX);
 	memcg_wb_domain_size_changed(memcg);
 }
@@ -6063,758 +3865,6 @@ static void mem_cgroup_css_rstat_flush(struct cgroup_subsys_state *css, int cpu)
 		atomic64_set(&memcg->vmstats->stats_updates, 0);
 }
 
-#ifdef CONFIG_MMU
-/* Handlers for move charge at task migration. */
-static int mem_cgroup_do_precharge(unsigned long count)
-{
-	int ret;
-
-	/* Try a single bulk charge without reclaim first, kswapd may wake */
-	ret = try_charge(mc.to, GFP_KERNEL & ~__GFP_DIRECT_RECLAIM, count);
-	if (!ret) {
-		mc.precharge += count;
-		return ret;
-	}
-
-	/* Try charges one by one with reclaim, but do not retry */
-	while (count--) {
-		ret = try_charge(mc.to, GFP_KERNEL | __GFP_NORETRY, 1);
-		if (ret)
-			return ret;
-		mc.precharge++;
-		cond_resched();
-	}
-	return 0;
-}
-
-union mc_target {
-	struct folio	*folio;
-	swp_entry_t	ent;
-};
-
-enum mc_target_type {
-	MC_TARGET_NONE = 0,
-	MC_TARGET_PAGE,
-	MC_TARGET_SWAP,
-	MC_TARGET_DEVICE,
-};
-
-static struct page *mc_handle_present_pte(struct vm_area_struct *vma,
-						unsigned long addr, pte_t ptent)
-{
-	struct page *page = vm_normal_page(vma, addr, ptent);
-
-	if (!page)
-		return NULL;
-	if (PageAnon(page)) {
-		if (!(mc.flags & MOVE_ANON))
-			return NULL;
-	} else {
-		if (!(mc.flags & MOVE_FILE))
-			return NULL;
-	}
-	get_page(page);
-
-	return page;
-}
-
-#if defined(CONFIG_SWAP) || defined(CONFIG_DEVICE_PRIVATE)
-static struct page *mc_handle_swap_pte(struct vm_area_struct *vma,
-			pte_t ptent, swp_entry_t *entry)
-{
-	struct page *page = NULL;
-	swp_entry_t ent = pte_to_swp_entry(ptent);
-
-	if (!(mc.flags & MOVE_ANON))
-		return NULL;
-
-	/*
-	 * Handle device private pages that are not accessible by the CPU, but
-	 * stored as special swap entries in the page table.
-	 */
-	if (is_device_private_entry(ent)) {
-		page = pfn_swap_entry_to_page(ent);
-		if (!get_page_unless_zero(page))
-			return NULL;
-		return page;
-	}
-
-	if (non_swap_entry(ent))
-		return NULL;
-
-	/*
-	 * Because swap_cache_get_folio() updates some statistics counter,
-	 * we call find_get_page() with swapper_space directly.
-	 */
-	page = find_get_page(swap_address_space(ent), swp_offset(ent));
-	entry->val = ent.val;
-
-	return page;
-}
-#else
-static struct page *mc_handle_swap_pte(struct vm_area_struct *vma,
-			pte_t ptent, swp_entry_t *entry)
-{
-	return NULL;
-}
-#endif
-
-static struct page *mc_handle_file_pte(struct vm_area_struct *vma,
-			unsigned long addr, pte_t ptent)
-{
-	unsigned long index;
-	struct folio *folio;
-
-	if (!vma->vm_file) /* anonymous vma */
-		return NULL;
-	if (!(mc.flags & MOVE_FILE))
-		return NULL;
-
-	/* folio is moved even if it's not RSS of this task(page-faulted). */
-	/* shmem/tmpfs may report page out on swap: account for that too. */
-	index = linear_page_index(vma, addr);
-	folio = filemap_get_incore_folio(vma->vm_file->f_mapping, index);
-	if (IS_ERR(folio))
-		return NULL;
-	return folio_file_page(folio, index);
-}
-
-/**
- * mem_cgroup_move_account - move account of the folio
- * @folio: The folio.
- * @compound: charge the page as compound or small page
- * @from: mem_cgroup which the folio is moved from.
- * @to:	mem_cgroup which the folio is moved to. @from != @to.
- *
- * The folio must be locked and not on the LRU.
- *
- * This function doesn't do "charge" to new cgroup and doesn't do "uncharge"
- * from old cgroup.
- */
-static int mem_cgroup_move_account(struct folio *folio,
-				   bool compound,
-				   struct mem_cgroup *from,
-				   struct mem_cgroup *to)
-{
-	struct lruvec *from_vec, *to_vec;
-	struct pglist_data *pgdat;
-	unsigned int nr_pages = compound ? folio_nr_pages(folio) : 1;
-	int nid, ret;
-
-	VM_BUG_ON(from == to);
-	VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio);
-	VM_BUG_ON_FOLIO(folio_test_lru(folio), folio);
-	VM_BUG_ON(compound && !folio_test_large(folio));
-
-	ret = -EINVAL;
-	if (folio_memcg(folio) != from)
-		goto out;
-
-	pgdat = folio_pgdat(folio);
-	from_vec = mem_cgroup_lruvec(from, pgdat);
-	to_vec = mem_cgroup_lruvec(to, pgdat);
-
-	folio_memcg_lock(folio);
-
-	if (folio_test_anon(folio)) {
-		if (folio_mapped(folio)) {
-			__mod_lruvec_state(from_vec, NR_ANON_MAPPED, -nr_pages);
-			__mod_lruvec_state(to_vec, NR_ANON_MAPPED, nr_pages);
-			if (folio_test_pmd_mappable(folio)) {
-				__mod_lruvec_state(from_vec, NR_ANON_THPS,
-						   -nr_pages);
-				__mod_lruvec_state(to_vec, NR_ANON_THPS,
-						   nr_pages);
-			}
-		}
-	} else {
-		__mod_lruvec_state(from_vec, NR_FILE_PAGES, -nr_pages);
-		__mod_lruvec_state(to_vec, NR_FILE_PAGES, nr_pages);
-
-		if (folio_test_swapbacked(folio)) {
-			__mod_lruvec_state(from_vec, NR_SHMEM, -nr_pages);
-			__mod_lruvec_state(to_vec, NR_SHMEM, nr_pages);
-		}
-
-		if (folio_mapped(folio)) {
-			__mod_lruvec_state(from_vec, NR_FILE_MAPPED, -nr_pages);
-			__mod_lruvec_state(to_vec, NR_FILE_MAPPED, nr_pages);
-		}
-
-		if (folio_test_dirty(folio)) {
-			struct address_space *mapping = folio_mapping(folio);
-
-			if (mapping_can_writeback(mapping)) {
-				__mod_lruvec_state(from_vec, NR_FILE_DIRTY,
-						   -nr_pages);
-				__mod_lruvec_state(to_vec, NR_FILE_DIRTY,
-						   nr_pages);
-			}
-		}
-	}
-
-#ifdef CONFIG_SWAP
-	if (folio_test_swapcache(folio)) {
-		__mod_lruvec_state(from_vec, NR_SWAPCACHE, -nr_pages);
-		__mod_lruvec_state(to_vec, NR_SWAPCACHE, nr_pages);
-	}
-#endif
-	if (folio_test_writeback(folio)) {
-		__mod_lruvec_state(from_vec, NR_WRITEBACK, -nr_pages);
-		__mod_lruvec_state(to_vec, NR_WRITEBACK, nr_pages);
-	}
-
-	/*
-	 * All state has been migrated, let's switch to the new memcg.
-	 *
-	 * It is safe to change page's memcg here because the page
-	 * is referenced, charged, isolated, and locked: we can't race
-	 * with (un)charging, migration, LRU putback, or anything else
-	 * that would rely on a stable page's memory cgroup.
-	 *
-	 * Note that folio_memcg_lock is a memcg lock, not a page lock,
-	 * to save space. As soon as we switch page's memory cgroup to a
-	 * new memcg that isn't locked, the above state can change
-	 * concurrently again. Make sure we're truly done with it.
-	 */
-	smp_mb();
-
-	css_get(&to->css);
-	css_put(&from->css);
-
-	folio->memcg_data = (unsigned long)to;
-
-	__folio_memcg_unlock(from);
-
-	ret = 0;
-	nid = folio_nid(folio);
-
-	local_irq_disable();
-	mem_cgroup_charge_statistics(to, nr_pages);
-	memcg_check_events(to, nid);
-	mem_cgroup_charge_statistics(from, -nr_pages);
-	memcg_check_events(from, nid);
-	local_irq_enable();
-out:
-	return ret;
-}
-
-/**
- * get_mctgt_type - get target type of moving charge
- * @vma: the vma the pte to be checked belongs
- * @addr: the address corresponding to the pte to be checked
- * @ptent: the pte to be checked
- * @target: the pointer the target page or swap ent will be stored(can be NULL)
- *
- * Context: Called with pte lock held.
- * Return:
- * * MC_TARGET_NONE - If the pte is not a target for move charge.
- * * MC_TARGET_PAGE - If the page corresponding to this pte is a target for
- *   move charge. If @target is not NULL, the folio is stored in target->folio
- *   with extra refcnt taken (Caller should release it).
- * * MC_TARGET_SWAP - If the swap entry corresponding to this pte is a
- *   target for charge migration.  If @target is not NULL, the entry is
- *   stored in target->ent.
- * * MC_TARGET_DEVICE - Like MC_TARGET_PAGE but page is device memory and
- *   thus not on the lru.  For now such page is charged like a regular page
- *   would be as it is just special memory taking the place of a regular page.
- *   See Documentations/vm/hmm.txt and include/linux/hmm.h
- */
-static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma,
-		unsigned long addr, pte_t ptent, union mc_target *target)
-{
-	struct page *page = NULL;
-	struct folio *folio;
-	enum mc_target_type ret = MC_TARGET_NONE;
-	swp_entry_t ent = { .val = 0 };
-
-	if (pte_present(ptent))
-		page = mc_handle_present_pte(vma, addr, ptent);
-	else if (pte_none_mostly(ptent))
-		/*
-		 * PTE markers should be treated as a none pte here, separated
-		 * from other swap handling below.
-		 */
-		page = mc_handle_file_pte(vma, addr, ptent);
-	else if (is_swap_pte(ptent))
-		page = mc_handle_swap_pte(vma, ptent, &ent);
-
-	if (page)
-		folio = page_folio(page);
-	if (target && page) {
-		if (!folio_trylock(folio)) {
-			folio_put(folio);
-			return ret;
-		}
-		/*
-		 * page_mapped() must be stable during the move. This
-		 * pte is locked, so if it's present, the page cannot
-		 * become unmapped. If it isn't, we have only partial
-		 * control over the mapped state: the page lock will
-		 * prevent new faults against pagecache and swapcache,
-		 * so an unmapped page cannot become mapped. However,
-		 * if the page is already mapped elsewhere, it can
-		 * unmap, and there is nothing we can do about it.
-		 * Alas, skip moving the page in this case.
-		 */
-		if (!pte_present(ptent) && page_mapped(page)) {
-			folio_unlock(folio);
-			folio_put(folio);
-			return ret;
-		}
-	}
-
-	if (!page && !ent.val)
-		return ret;
-	if (page) {
-		/*
-		 * Do only loose check w/o serialization.
-		 * mem_cgroup_move_account() checks the page is valid or
-		 * not under LRU exclusion.
-		 */
-		if (folio_memcg(folio) == mc.from) {
-			ret = MC_TARGET_PAGE;
-			if (folio_is_device_private(folio) ||
-			    folio_is_device_coherent(folio))
-				ret = MC_TARGET_DEVICE;
-			if (target)
-				target->folio = folio;
-		}
-		if (!ret || !target) {
-			if (target)
-				folio_unlock(folio);
-			folio_put(folio);
-		}
-	}
-	/*
-	 * There is a swap entry and a page doesn't exist or isn't charged.
-	 * But we cannot move a tail-page in a THP.
-	 */
-	if (ent.val && !ret && (!page || !PageTransCompound(page)) &&
-	    mem_cgroup_id(mc.from) == lookup_swap_cgroup_id(ent)) {
-		ret = MC_TARGET_SWAP;
-		if (target)
-			target->ent = ent;
-	}
-	return ret;
-}
-
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-/*
- * We don't consider PMD mapped swapping or file mapped pages because THP does
- * not support them for now.
- * Caller should make sure that pmd_trans_huge(pmd) is true.
- */
-static enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma,
-		unsigned long addr, pmd_t pmd, union mc_target *target)
-{
-	struct page *page = NULL;
-	struct folio *folio;
-	enum mc_target_type ret = MC_TARGET_NONE;
-
-	if (unlikely(is_swap_pmd(pmd))) {
-		VM_BUG_ON(thp_migration_supported() &&
-				  !is_pmd_migration_entry(pmd));
-		return ret;
-	}
-	page = pmd_page(pmd);
-	VM_BUG_ON_PAGE(!page || !PageHead(page), page);
-	folio = page_folio(page);
-	if (!(mc.flags & MOVE_ANON))
-		return ret;
-	if (folio_memcg(folio) == mc.from) {
-		ret = MC_TARGET_PAGE;
-		if (target) {
-			folio_get(folio);
-			if (!folio_trylock(folio)) {
-				folio_put(folio);
-				return MC_TARGET_NONE;
-			}
-			target->folio = folio;
-		}
-	}
-	return ret;
-}
-#else
-static inline enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma,
-		unsigned long addr, pmd_t pmd, union mc_target *target)
-{
-	return MC_TARGET_NONE;
-}
-#endif
-
-static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd,
-					unsigned long addr, unsigned long end,
-					struct mm_walk *walk)
-{
-	struct vm_area_struct *vma = walk->vma;
-	pte_t *pte;
-	spinlock_t *ptl;
-
-	ptl = pmd_trans_huge_lock(pmd, vma);
-	if (ptl) {
-		/*
-		 * Note their can not be MC_TARGET_DEVICE for now as we do not
-		 * support transparent huge page with MEMORY_DEVICE_PRIVATE but
-		 * this might change.
-		 */
-		if (get_mctgt_type_thp(vma, addr, *pmd, NULL) == MC_TARGET_PAGE)
-			mc.precharge += HPAGE_PMD_NR;
-		spin_unlock(ptl);
-		return 0;
-	}
-
-	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
-	if (!pte)
-		return 0;
-	for (; addr != end; pte++, addr += PAGE_SIZE)
-		if (get_mctgt_type(vma, addr, ptep_get(pte), NULL))
-			mc.precharge++;	/* increment precharge temporarily */
-	pte_unmap_unlock(pte - 1, ptl);
-	cond_resched();
-
-	return 0;
-}
-
-static const struct mm_walk_ops precharge_walk_ops = {
-	.pmd_entry	= mem_cgroup_count_precharge_pte_range,
-	.walk_lock	= PGWALK_RDLOCK,
-};
-
-static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm)
-{
-	unsigned long precharge;
-
-	mmap_read_lock(mm);
-	walk_page_range(mm, 0, ULONG_MAX, &precharge_walk_ops, NULL);
-	mmap_read_unlock(mm);
-
-	precharge = mc.precharge;
-	mc.precharge = 0;
-
-	return precharge;
-}
-
-static int mem_cgroup_precharge_mc(struct mm_struct *mm)
-{
-	unsigned long precharge = mem_cgroup_count_precharge(mm);
-
-	VM_BUG_ON(mc.moving_task);
-	mc.moving_task = current;
-	return mem_cgroup_do_precharge(precharge);
-}
-
-/* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */
-static void __mem_cgroup_clear_mc(void)
-{
-	struct mem_cgroup *from = mc.from;
-	struct mem_cgroup *to = mc.to;
-
-	/* we must uncharge all the leftover precharges from mc.to */
-	if (mc.precharge) {
-		mem_cgroup_cancel_charge(mc.to, mc.precharge);
-		mc.precharge = 0;
-	}
-	/*
-	 * we didn't uncharge from mc.from at mem_cgroup_move_account(), so
-	 * we must uncharge here.
-	 */
-	if (mc.moved_charge) {
-		mem_cgroup_cancel_charge(mc.from, mc.moved_charge);
-		mc.moved_charge = 0;
-	}
-	/* we must fixup refcnts and charges */
-	if (mc.moved_swap) {
-		/* uncharge swap account from the old cgroup */
-		if (!mem_cgroup_is_root(mc.from))
-			page_counter_uncharge(&mc.from->memsw, mc.moved_swap);
-
-		mem_cgroup_id_put_many(mc.from, mc.moved_swap);
-
-		/*
-		 * we charged both to->memory and to->memsw, so we
-		 * should uncharge to->memory.
-		 */
-		if (!mem_cgroup_is_root(mc.to))
-			page_counter_uncharge(&mc.to->memory, mc.moved_swap);
-
-		mc.moved_swap = 0;
-	}
-	memcg_oom_recover(from);
-	memcg_oom_recover(to);
-	wake_up_all(&mc.waitq);
-}
-
-static void mem_cgroup_clear_mc(void)
-{
-	struct mm_struct *mm = mc.mm;
-
-	/*
-	 * we must clear moving_task before waking up waiters at the end of
-	 * task migration.
-	 */
-	mc.moving_task = NULL;
-	__mem_cgroup_clear_mc();
-	spin_lock(&mc.lock);
-	mc.from = NULL;
-	mc.to = NULL;
-	mc.mm = NULL;
-	spin_unlock(&mc.lock);
-
-	mmput(mm);
-}
-
-static int mem_cgroup_can_attach(struct cgroup_taskset *tset)
-{
-	struct cgroup_subsys_state *css;
-	struct mem_cgroup *memcg = NULL; /* unneeded init to make gcc happy */
-	struct mem_cgroup *from;
-	struct task_struct *leader, *p;
-	struct mm_struct *mm;
-	unsigned long move_flags;
-	int ret = 0;
-
-	/* charge immigration isn't supported on the default hierarchy */
-	if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
-		return 0;
-
-	/*
-	 * Multi-process migrations only happen on the default hierarchy
-	 * where charge immigration is not used.  Perform charge
-	 * immigration if @tset contains a leader and whine if there are
-	 * multiple.
-	 */
-	p = NULL;
-	cgroup_taskset_for_each_leader(leader, css, tset) {
-		WARN_ON_ONCE(p);
-		p = leader;
-		memcg = mem_cgroup_from_css(css);
-	}
-	if (!p)
-		return 0;
-
-	/*
-	 * We are now committed to this value whatever it is. Changes in this
-	 * tunable will only affect upcoming migrations, not the current one.
-	 * So we need to save it, and keep it going.
-	 */
-	move_flags = READ_ONCE(memcg->move_charge_at_immigrate);
-	if (!move_flags)
-		return 0;
-
-	from = mem_cgroup_from_task(p);
-
-	VM_BUG_ON(from == memcg);
-
-	mm = get_task_mm(p);
-	if (!mm)
-		return 0;
-	/* We move charges only when we move a owner of the mm */
-	if (mm->owner == p) {
-		VM_BUG_ON(mc.from);
-		VM_BUG_ON(mc.to);
-		VM_BUG_ON(mc.precharge);
-		VM_BUG_ON(mc.moved_charge);
-		VM_BUG_ON(mc.moved_swap);
-
-		spin_lock(&mc.lock);
-		mc.mm = mm;
-		mc.from = from;
-		mc.to = memcg;
-		mc.flags = move_flags;
-		spin_unlock(&mc.lock);
-		/* We set mc.moving_task later */
-
-		ret = mem_cgroup_precharge_mc(mm);
-		if (ret)
-			mem_cgroup_clear_mc();
-	} else {
-		mmput(mm);
-	}
-	return ret;
-}
-
-static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset)
-{
-	if (mc.to)
-		mem_cgroup_clear_mc();
-}
-
-static int mem_cgroup_move_charge_pte_range(pmd_t *pmd,
-				unsigned long addr, unsigned long end,
-				struct mm_walk *walk)
-{
-	int ret = 0;
-	struct vm_area_struct *vma = walk->vma;
-	pte_t *pte;
-	spinlock_t *ptl;
-	enum mc_target_type target_type;
-	union mc_target target;
-	struct folio *folio;
-
-	ptl = pmd_trans_huge_lock(pmd, vma);
-	if (ptl) {
-		if (mc.precharge < HPAGE_PMD_NR) {
-			spin_unlock(ptl);
-			return 0;
-		}
-		target_type = get_mctgt_type_thp(vma, addr, *pmd, &target);
-		if (target_type == MC_TARGET_PAGE) {
-			folio = target.folio;
-			if (folio_isolate_lru(folio)) {
-				if (!mem_cgroup_move_account(folio, true,
-							     mc.from, mc.to)) {
-					mc.precharge -= HPAGE_PMD_NR;
-					mc.moved_charge += HPAGE_PMD_NR;
-				}
-				folio_putback_lru(folio);
-			}
-			folio_unlock(folio);
-			folio_put(folio);
-		} else if (target_type == MC_TARGET_DEVICE) {
-			folio = target.folio;
-			if (!mem_cgroup_move_account(folio, true,
-						     mc.from, mc.to)) {
-				mc.precharge -= HPAGE_PMD_NR;
-				mc.moved_charge += HPAGE_PMD_NR;
-			}
-			folio_unlock(folio);
-			folio_put(folio);
-		}
-		spin_unlock(ptl);
-		return 0;
-	}
-
-retry:
-	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
-	if (!pte)
-		return 0;
-	for (; addr != end; addr += PAGE_SIZE) {
-		pte_t ptent = ptep_get(pte++);
-		bool device = false;
-		swp_entry_t ent;
-
-		if (!mc.precharge)
-			break;
-
-		switch (get_mctgt_type(vma, addr, ptent, &target)) {
-		case MC_TARGET_DEVICE:
-			device = true;
-			fallthrough;
-		case MC_TARGET_PAGE:
-			folio = target.folio;
-			/*
-			 * We can have a part of the split pmd here. Moving it
-			 * can be done but it would be too convoluted so simply
-			 * ignore such a partial THP and keep it in original
-			 * memcg. There should be somebody mapping the head.
-			 */
-			if (folio_test_large(folio))
-				goto put;
-			if (!device && !folio_isolate_lru(folio))
-				goto put;
-			if (!mem_cgroup_move_account(folio, false,
-						mc.from, mc.to)) {
-				mc.precharge--;
-				/* we uncharge from mc.from later. */
-				mc.moved_charge++;
-			}
-			if (!device)
-				folio_putback_lru(folio);
-put:			/* get_mctgt_type() gets & locks the page */
-			folio_unlock(folio);
-			folio_put(folio);
-			break;
-		case MC_TARGET_SWAP:
-			ent = target.ent;
-			if (!mem_cgroup_move_swap_account(ent, mc.from, mc.to)) {
-				mc.precharge--;
-				mem_cgroup_id_get_many(mc.to, 1);
-				/* we fixup other refcnts and charges later. */
-				mc.moved_swap++;
-			}
-			break;
-		default:
-			break;
-		}
-	}
-	pte_unmap_unlock(pte - 1, ptl);
-	cond_resched();
-
-	if (addr != end) {
-		/*
-		 * We have consumed all precharges we got in can_attach().
-		 * We try charge one by one, but don't do any additional
-		 * charges to mc.to if we have failed in charge once in attach()
-		 * phase.
-		 */
-		ret = mem_cgroup_do_precharge(1);
-		if (!ret)
-			goto retry;
-	}
-
-	return ret;
-}
-
-static const struct mm_walk_ops charge_walk_ops = {
-	.pmd_entry	= mem_cgroup_move_charge_pte_range,
-	.walk_lock	= PGWALK_RDLOCK,
-};
-
-static void mem_cgroup_move_charge(void)
-{
-	lru_add_drain_all();
-	/*
-	 * Signal folio_memcg_lock() to take the memcg's move_lock
-	 * while we're moving its pages to another memcg. Then wait
-	 * for already started RCU-only updates to finish.
-	 */
-	atomic_inc(&mc.from->moving_account);
-	synchronize_rcu();
-retry:
-	if (unlikely(!mmap_read_trylock(mc.mm))) {
-		/*
-		 * Someone who are holding the mmap_lock might be waiting in
-		 * waitq. So we cancel all extra charges, wake up all waiters,
-		 * and retry. Because we cancel precharges, we might not be able
-		 * to move enough charges, but moving charge is a best-effort
-		 * feature anyway, so it wouldn't be a big problem.
-		 */
-		__mem_cgroup_clear_mc();
-		cond_resched();
-		goto retry;
-	}
-	/*
-	 * When we have consumed all precharges and failed in doing
-	 * additional charge, the page walk just aborts.
-	 */
-	walk_page_range(mc.mm, 0, ULONG_MAX, &charge_walk_ops, NULL);
-	mmap_read_unlock(mc.mm);
-	atomic_dec(&mc.from->moving_account);
-}
-
-static void mem_cgroup_move_task(void)
-{
-	if (mc.to) {
-		mem_cgroup_move_charge();
-		mem_cgroup_clear_mc();
-	}
-}
-
-#else	/* !CONFIG_MMU */
-static int mem_cgroup_can_attach(struct cgroup_taskset *tset)
-{
-	return 0;
-}
-static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset)
-{
-}
-static void mem_cgroup_move_task(void)
-{
-}
-#endif
-
-#ifdef CONFIG_MEMCG_KMEM
 static void mem_cgroup_fork(struct task_struct *task)
 {
 	/*
@@ -6842,7 +3892,6 @@ static void mem_cgroup_exit(struct task_struct *task)
 	 */
 	task->objcg = NULL;
 }
-#endif
 
 #ifdef CONFIG_LRU_GEN
 static void mem_cgroup_lru_gen_attach(struct cgroup_taskset *tset)
@@ -6866,7 +3915,6 @@ static void mem_cgroup_lru_gen_attach(struct cgroup_taskset *tset)
 static void mem_cgroup_lru_gen_attach(struct cgroup_taskset *tset) {}
 #endif /* CONFIG_LRU_GEN */
 
-#ifdef CONFIG_MEMCG_KMEM
 static void mem_cgroup_kmem_attach(struct cgroup_taskset *tset)
 {
 	struct task_struct *task;
@@ -6877,17 +3925,12 @@ static void mem_cgroup_kmem_attach(struct cgroup_taskset *tset)
 		set_bit(CURRENT_OBJCG_UPDATE_BIT, (unsigned long *)&task->objcg);
 	}
 }
-#else
-static void mem_cgroup_kmem_attach(struct cgroup_taskset *tset) {}
-#endif /* CONFIG_MEMCG_KMEM */
 
-#if defined(CONFIG_LRU_GEN) || defined(CONFIG_MEMCG_KMEM)
 static void mem_cgroup_attach(struct cgroup_taskset *tset)
 {
 	mem_cgroup_lru_gen_attach(tset);
 	mem_cgroup_kmem_attach(tset);
 }
-#endif
 
 static int seq_puts_memcg_tunable(struct seq_file *m, unsigned long value)
 {
@@ -7000,7 +4043,7 @@ static ssize_t memory_high_write(struct kernfs_open_file *of,
 		}
 
 		reclaimed = try_to_free_mem_cgroup_pages(memcg, nr_pages - high,
-					GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP);
+					GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP, NULL);
 
 		if (!reclaimed && !nr_retries--)
 			break;
@@ -7049,7 +4092,7 @@ static ssize_t memory_max_write(struct kernfs_open_file *of,
 
 		if (nr_reclaims) {
 			if (!try_to_free_mem_cgroup_pages(memcg, nr_pages - max,
-					GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP))
+					GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP, NULL))
 				nr_reclaims--;
 			continue;
 		}
@@ -7095,7 +4138,7 @@ static int memory_events_local_show(struct seq_file *m, void *v)
 	return 0;
 }
 
-static int memory_stat_show(struct seq_file *m, void *v)
+int memory_stat_show(struct seq_file *m, void *v)
 {
 	struct mem_cgroup *memcg = mem_cgroup_from_seq(m);
 	char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
@@ -7179,19 +4222,50 @@ static ssize_t memory_oom_group_write(struct kernfs_open_file *of,
 	return nbytes;
 }
 
+enum {
+	MEMORY_RECLAIM_SWAPPINESS = 0,
+	MEMORY_RECLAIM_NULL,
+};
+
+static const match_table_t tokens = {
+	{ MEMORY_RECLAIM_SWAPPINESS, "swappiness=%d"},
+	{ MEMORY_RECLAIM_NULL, NULL },
+};
+
 static ssize_t memory_reclaim(struct kernfs_open_file *of, char *buf,
 			      size_t nbytes, loff_t off)
 {
 	struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
 	unsigned int nr_retries = MAX_RECLAIM_RETRIES;
 	unsigned long nr_to_reclaim, nr_reclaimed = 0;
+	int swappiness = -1;
 	unsigned int reclaim_options;
-	int err;
+	char *old_buf, *start;
+	substring_t args[MAX_OPT_ARGS];
 
 	buf = strstrip(buf);
-	err = page_counter_memparse(buf, "", &nr_to_reclaim);
-	if (err)
-		return err;
+
+	old_buf = buf;
+	nr_to_reclaim = memparse(buf, &buf) / PAGE_SIZE;
+	if (buf == old_buf)
+		return -EINVAL;
+
+	buf = strstrip(buf);
+
+	while ((start = strsep(&buf, " ")) != NULL) {
+		if (!strlen(start))
+			continue;
+		switch (match_token(start, tokens, args)) {
+		case MEMORY_RECLAIM_SWAPPINESS:
+			if (match_int(&args[0], &swappiness))
+				return -EINVAL;
+			if (swappiness < MIN_SWAPPINESS || swappiness > MAX_SWAPPINESS)
+				return -EINVAL;
+			break;
+		default:
+			return -EINVAL;
+		}
+	}
 
 	reclaim_options	= MEMCG_RECLAIM_MAY_SWAP | MEMCG_RECLAIM_PROACTIVE;
 	while (nr_reclaimed < nr_to_reclaim) {
@@ -7211,7 +4285,9 @@ static ssize_t memory_reclaim(struct kernfs_open_file *of, char *buf,
 			lru_add_drain_all();
 
 		reclaimed = try_to_free_mem_cgroup_pages(memcg,
-					batch_size, GFP_KERNEL, reclaim_options);
+					batch_size, GFP_KERNEL,
+					reclaim_options,
+					swappiness == -1 ? NULL : &swappiness);
 
 		if (!reclaimed && !nr_retries--)
 			return -EAGAIN;
@@ -7301,137 +4377,19 @@ struct cgroup_subsys memory_cgrp_subsys = {
 	.css_free = mem_cgroup_css_free,
 	.css_reset = mem_cgroup_css_reset,
 	.css_rstat_flush = mem_cgroup_css_rstat_flush,
-	.can_attach = mem_cgroup_can_attach,
-#if defined(CONFIG_LRU_GEN) || defined(CONFIG_MEMCG_KMEM)
 	.attach = mem_cgroup_attach,
-#endif
-	.cancel_attach = mem_cgroup_cancel_attach,
-	.post_attach = mem_cgroup_move_task,
-#ifdef CONFIG_MEMCG_KMEM
 	.fork = mem_cgroup_fork,
 	.exit = mem_cgroup_exit,
-#endif
 	.dfl_cftypes = memory_files,
+#ifdef CONFIG_MEMCG_V1
+	.can_attach = memcg1_can_attach,
+	.cancel_attach = memcg1_cancel_attach,
+	.post_attach = memcg1_move_task,
 	.legacy_cftypes = mem_cgroup_legacy_files,
+#endif
 	.early_init = 0,
 };
 
-/*
- * This function calculates an individual cgroup's effective
- * protection which is derived from its own memory.min/low, its
- * parent's and siblings' settings, as well as the actual memory
- * distribution in the tree.
- *
- * The following rules apply to the effective protection values:
- *
- * 1. At the first level of reclaim, effective protection is equal to
- *    the declared protection in memory.min and memory.low.
- *
- * 2. To enable safe delegation of the protection configuration, at
- *    subsequent levels the effective protection is capped to the
- *    parent's effective protection.
- *
- * 3. To make complex and dynamic subtrees easier to configure, the
- *    user is allowed to overcommit the declared protection at a given
- *    level. If that is the case, the parent's effective protection is
- *    distributed to the children in proportion to how much protection
- *    they have declared and how much of it they are utilizing.
- *
- *    This makes distribution proportional, but also work-conserving:
- *    if one cgroup claims much more protection than it uses memory,
- *    the unused remainder is available to its siblings.
- *
- * 4. Conversely, when the declared protection is undercommitted at a
- *    given level, the distribution of the larger parental protection
- *    budget is NOT proportional. A cgroup's protection from a sibling
- *    is capped to its own memory.min/low setting.
- *
- * 5. However, to allow protecting recursive subtrees from each other
- *    without having to declare each individual cgroup's fixed share
- *    of the ancestor's claim to protection, any unutilized -
- *    "floating" - protection from up the tree is distributed in
- *    proportion to each cgroup's *usage*. This makes the protection
- *    neutral wrt sibling cgroups and lets them compete freely over
- *    the shared parental protection budget, but it protects the
- *    subtree as a whole from neighboring subtrees.
- *
- * Note that 4. and 5. are not in conflict: 4. is about protecting
- * against immediate siblings whereas 5. is about protecting against
- * neighboring subtrees.
- */
-static unsigned long effective_protection(unsigned long usage,
-					  unsigned long parent_usage,
-					  unsigned long setting,
-					  unsigned long parent_effective,
-					  unsigned long siblings_protected)
-{
-	unsigned long protected;
-	unsigned long ep;
-
-	protected = min(usage, setting);
-	/*
-	 * If all cgroups at this level combined claim and use more
-	 * protection than what the parent affords them, distribute
-	 * shares in proportion to utilization.
-	 *
-	 * We are using actual utilization rather than the statically
-	 * claimed protection in order to be work-conserving: claimed
-	 * but unused protection is available to siblings that would
-	 * otherwise get a smaller chunk than what they claimed.
-	 */
-	if (siblings_protected > parent_effective)
-		return protected * parent_effective / siblings_protected;
-
-	/*
-	 * Ok, utilized protection of all children is within what the
-	 * parent affords them, so we know whatever this child claims
-	 * and utilizes is effectively protected.
-	 *
-	 * If there is unprotected usage beyond this value, reclaim
-	 * will apply pressure in proportion to that amount.
-	 *
-	 * If there is unutilized protection, the cgroup will be fully
-	 * shielded from reclaim, but we do return a smaller value for
-	 * protection than what the group could enjoy in theory. This
-	 * is okay. With the overcommit distribution above, effective
-	 * protection is always dependent on how memory is actually
-	 * consumed among the siblings anyway.
-	 */
-	ep = protected;
-
-	/*
-	 * If the children aren't claiming (all of) the protection
-	 * afforded to them by the parent, distribute the remainder in
-	 * proportion to the (unprotected) memory of each cgroup. That
-	 * way, cgroups that aren't explicitly prioritized wrt each
-	 * other compete freely over the allowance, but they are
-	 * collectively protected from neighboring trees.
-	 *
-	 * We're using unprotected memory for the weight so that if
-	 * some cgroups DO claim explicit protection, we don't protect
-	 * the same bytes twice.
-	 *
-	 * Check both usage and parent_usage against the respective
-	 * protected values. One should imply the other, but they
-	 * aren't read atomically - make sure the division is sane.
-	 */
-	if (!(cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_RECURSIVE_PROT))
-		return ep;
-	if (parent_effective > siblings_protected &&
-	    parent_usage > siblings_protected &&
-	    usage > protected) {
-		unsigned long unclaimed;
-
-		unclaimed = parent_effective - siblings_protected;
-		unclaimed *= usage - protected;
-		unclaimed /= parent_usage - siblings_protected;
-
-		ep += unclaimed;
-	}
-
-	return ep;
-}
-
 /**
  * mem_cgroup_calculate_protection - check if memory consumption is in the normal range
  * @root: the top ancestor of the sub-tree being checked
@@ -7443,8 +4401,8 @@ static unsigned long effective_protection(unsigned long usage,
 void mem_cgroup_calculate_protection(struct mem_cgroup *root,
 				     struct mem_cgroup *memcg)
 {
-	unsigned long usage, parent_usage;
-	struct mem_cgroup *parent;
+	bool recursive_protection =
+		cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_RECURSIVE_PROT;
 
 	if (mem_cgroup_disabled())
 		return;
@@ -7452,39 +4410,7 @@ void mem_cgroup_calculate_protection(struct mem_cgroup *root,
 	if (!root)
 		root = root_mem_cgroup;
 
-	/*
-	 * Effective values of the reclaim targets are ignored so they
-	 * can be stale. Have a look at mem_cgroup_protection for more
-	 * details.
-	 * TODO: calculation should be more robust so that we do not need
-	 * that special casing.
-	 */
-	if (memcg == root)
-		return;
-
-	usage = page_counter_read(&memcg->memory);
-	if (!usage)
-		return;
-
-	parent = parent_mem_cgroup(memcg);
-
-	if (parent == root) {
-		memcg->memory.emin = READ_ONCE(memcg->memory.min);
-		memcg->memory.elow = READ_ONCE(memcg->memory.low);
-		return;
-	}
-
-	parent_usage = page_counter_read(&parent->memory);
-
-	WRITE_ONCE(memcg->memory.emin, effective_protection(usage, parent_usage,
-			READ_ONCE(memcg->memory.min),
-			READ_ONCE(parent->memory.emin),
-			atomic_long_read(&parent->memory.children_min_usage)));
-
-	WRITE_ONCE(memcg->memory.elow, effective_protection(usage, parent_usage,
-			READ_ONCE(memcg->memory.low),
-			READ_ONCE(parent->memory.elow),
-			atomic_long_read(&parent->memory.children_low_usage)));
+	page_counter_calculate_protection(&root->memory, &memcg->memory, recursive_protection);
 }
 
 static int charge_memcg(struct folio *folio, struct mem_cgroup *memcg,
@@ -7637,15 +4563,17 @@ static void uncharge_batch(const struct uncharge_gather *ug)
 		page_counter_uncharge(&ug->memcg->memory, ug->nr_memory);
 		if (do_memsw_account())
 			page_counter_uncharge(&ug->memcg->memsw, ug->nr_memory);
-		if (ug->nr_kmem)
-			memcg_account_kmem(ug->memcg, -ug->nr_kmem);
-		memcg_oom_recover(ug->memcg);
+		if (ug->nr_kmem) {
+			mod_memcg_state(ug->memcg, MEMCG_KMEM, -ug->nr_kmem);
+			memcg1_account_kmem(ug->memcg, -ug->nr_kmem);
+		}
+		memcg1_oom_recover(ug->memcg);
 	}
 
 	local_irq_save(flags);
 	__count_memcg_events(ug->memcg, PGPGOUT, ug->pgpgout);
 	__this_cpu_add(ug->memcg->vmstats_percpu->nr_page_events, ug->nr_memory);
-	memcg_check_events(ug->memcg, ug->nid);
+	memcg1_check_events(ug->memcg, ug->nid);
 	local_irq_restore(flags);
 
 	/* drop reference from uncharge_folio */
@@ -7784,7 +4712,7 @@ void mem_cgroup_replace_folio(struct folio *old, struct folio *new)
 
 	local_irq_save(flags);
 	mem_cgroup_charge_statistics(memcg, nr_pages);
-	memcg_check_events(memcg, folio_nid(new));
+	memcg1_check_events(memcg, folio_nid(new));
 	local_irq_restore(flags);
 }
 
@@ -7807,6 +4735,7 @@ void mem_cgroup_migrate(struct folio *old, struct folio *new)
 	VM_BUG_ON_FOLIO(!folio_test_locked(new), new);
 	VM_BUG_ON_FOLIO(folio_test_anon(old) != folio_test_anon(new), new);
 	VM_BUG_ON_FOLIO(folio_nr_pages(old) != folio_nr_pages(new), new);
+	VM_BUG_ON_FOLIO(folio_test_lru(old), old);
 
 	if (mem_cgroup_disabled())
 		return;
@@ -7844,7 +4773,7 @@ void mem_cgroup_sk_alloc(struct sock *sk)
 	memcg = mem_cgroup_from_task(current);
 	if (mem_cgroup_is_root(memcg))
 		goto out;
-	if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && !memcg->tcpmem_active)
+	if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && !memcg1_tcpmem_active(memcg))
 		goto out;
 	if (css_tryget(&memcg->css))
 		sk->sk_memcg = memcg;
@@ -7870,20 +4799,8 @@ void mem_cgroup_sk_free(struct sock *sk)
 bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages,
 			     gfp_t gfp_mask)
 {
-	if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) {
-		struct page_counter *fail;
-
-		if (page_counter_try_charge(&memcg->tcpmem, nr_pages, &fail)) {
-			memcg->tcpmem_pressure = 0;
-			return true;
-		}
-		memcg->tcpmem_pressure = 1;
-		if (gfp_mask & __GFP_NOFAIL) {
-			page_counter_charge(&memcg->tcpmem, nr_pages);
-			return true;
-		}
-		return false;
-	}
+	if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
+		return memcg1_charge_skmem(memcg, nr_pages, gfp_mask);
 
 	if (try_charge(memcg, gfp_mask, nr_pages) == 0) {
 		mod_memcg_state(memcg, MEMCG_SOCK, nr_pages);
@@ -7901,7 +4818,7 @@ bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages,
 void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages)
 {
 	if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) {
-		page_counter_uncharge(&memcg->tcpmem, nr_pages);
+		memcg1_uncharge_skmem(memcg, nr_pages);
 		return;
 	}
 
@@ -7938,7 +4855,7 @@ __setup("cgroup.memory=", cgroup_memory);
  */
 static int __init mem_cgroup_init(void)
 {
-	int cpu, node;
+	int cpu;
 
 	/*
 	 * Currently s32 type (can refer to struct batched_lruvec_stat) is
@@ -7955,17 +4872,6 @@ static int __init mem_cgroup_init(void)
 		INIT_WORK(&per_cpu_ptr(&memcg_stock, cpu)->work,
 			  drain_local_stock);
 
-	for_each_node(node) {
-		struct mem_cgroup_tree_per_node *rtpn;
-
-		rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, node);
-
-		rtpn->rb_root = RB_ROOT;
-		rtpn->rb_rightmost = NULL;
-		spin_lock_init(&rtpn->lock);
-		soft_limit_tree.rb_tree_per_node[node] = rtpn;
-	}
-
 	return 0;
 }
 subsys_initcall(mem_cgroup_init);
@@ -8052,7 +4958,7 @@ void mem_cgroup_swapout(struct folio *folio, swp_entry_t entry)
 	memcg_stats_lock();
 	mem_cgroup_charge_statistics(memcg, -nr_entries);
 	memcg_stats_unlock();
-	memcg_check_events(memcg, folio_nid(folio));
+	memcg1_check_events(memcg, folio_nid(folio));
 
 	css_put(&memcg->css);
 }
@@ -8293,34 +5199,7 @@ static struct cftype swap_files[] = {
 	{ }	/* terminate */
 };
 
-static struct cftype memsw_files[] = {
-	{
-		.name = "memsw.usage_in_bytes",
-		.private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE),
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{
-		.name = "memsw.max_usage_in_bytes",
-		.private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE),
-		.write = mem_cgroup_reset,
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{
-		.name = "memsw.limit_in_bytes",
-		.private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT),
-		.write = mem_cgroup_write,
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{
-		.name = "memsw.failcnt",
-		.private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT),
-		.write = mem_cgroup_reset,
-		.read_u64 = mem_cgroup_read_u64,
-	},
-	{ },	/* terminate */
-};
-
-#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP)
+#ifdef CONFIG_ZSWAP
 /**
  * obj_cgroup_may_zswap - check if this cgroup can zswap
  * @objcg: the object cgroup
@@ -8423,7 +5302,7 @@ void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size)
 bool mem_cgroup_zswap_writeback_enabled(struct mem_cgroup *memcg)
 {
 	/* if zswap is disabled, do not block pages going to the swapping device */
-	return !is_zswap_enabled() || !memcg || READ_ONCE(memcg->zswap_writeback);
+	return !zswap_is_enabled() || !memcg || READ_ONCE(memcg->zswap_writeback);
 }
 
 static u64 zswap_current_read(struct cgroup_subsys_state *css,
@@ -8502,7 +5381,7 @@ static struct cftype zswap_files[] = {
 	},
 	{ }	/* terminate */
 };
-#endif /* CONFIG_MEMCG_KMEM && CONFIG_ZSWAP */
+#endif /* CONFIG_ZSWAP */
 
 static int __init mem_cgroup_swap_init(void)
 {
@@ -8510,8 +5389,10 @@ static int __init mem_cgroup_swap_init(void)
 		return 0;
 
 	WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, swap_files));
+#ifdef CONFIG_MEMCG_V1
 	WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys, memsw_files));
-#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP)
+#endif
+#ifdef CONFIG_ZSWAP
 	WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, zswap_files));
 #endif
 	return 0;