mm: memcg: put memcg1-specific struct mem_cgroup's members under CONFIG_MEMCG_V1

Put memcg1-specific members of struct mem_cgroup under the CONFIG_MEMCG_V1
config option.  Also group them close to the end of struct mem_cgroup just
before the dynamic per-node part.

Link: https://lkml.kernel.org/r/20240628210317.272856-7-roman.gushchin@linux.devSigned-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

include/linux/memcontrol.h

@@ -188,10 +188,6 @@ struct mem_cgroup {
 		struct page_counter memsw;	/* v1 only */
 	};
 
-	/* Legacy consumer-oriented counters */
-	struct page_counter kmem;		/* v1 only */
-	struct page_counter tcpmem;		/* v1 only */
-
 	/* Range enforcement for interrupt charges */
 	struct work_struct high_work;
 
@@ -205,8 +201,6 @@ struct mem_cgroup {
 	bool zswap_writeback;
 #endif
 
-	unsigned long soft_limit;
-
 	/* vmpressure notifications */
 	struct vmpressure vmpressure;
 
@@ -215,13 +209,7 @@ struct mem_cgroup {
 	 */
 	bool oom_group;
 
-	/* protected by memcg_oom_lock */
-	bool		oom_lock;
-	int		under_oom;
-
 	int swappiness;
-	/* OOM-Killer disable */
-	int		oom_kill_disable;
 
 	/* memory.events and memory.events.local */
 	struct cgroup_file events_file;
@@ -230,27 +218,6 @@ struct mem_cgroup {
 	/* handle for "memory.swap.events" */
 	struct cgroup_file swap_events_file;
 
-	/* protect arrays of thresholds */
-	struct mutex thresholds_lock;
-
-	/* thresholds for memory usage. RCU-protected */
-	struct mem_cgroup_thresholds thresholds;
-
-	/* thresholds for mem+swap usage. RCU-protected */
-	struct mem_cgroup_thresholds memsw_thresholds;
-
-	/* For oom notifier event fd */
-	struct list_head oom_notify;
-
-	/*
-	 * Should we move charges of a task when a task is moved into this
-	 * mem_cgroup ? And what type of charges should we move ?
-	 */
-	unsigned long move_charge_at_immigrate;
-	/* taken only while moving_account > 0 */
-	spinlock_t		move_lock;
-	unsigned long		move_lock_flags;
-
 	CACHELINE_PADDING(_pad1_);
 
 	/* memory.stat */
@@ -267,10 +234,6 @@ struct mem_cgroup {
 	 */
 	unsigned long		socket_pressure;
 
-	/* Legacy tcp memory accounting */
-	bool			tcpmem_active;
-	int			tcpmem_pressure;
-
 #ifdef CONFIG_MEMCG_KMEM
 	int kmemcg_id;
 	/*
@@ -284,14 +247,6 @@ struct mem_cgroup {
 	struct list_head objcg_list;
 #endif
 
-	CACHELINE_PADDING(_pad2_);
-
-	/*
-	 * set > 0 if pages under this cgroup are moving to other cgroup.
-	 */
-	atomic_t		moving_account;
-	struct task_struct	*move_lock_task;
-
 	struct memcg_vmstats_percpu __percpu *vmstats_percpu;
 
 #ifdef CONFIG_CGROUP_WRITEBACK
@@ -300,10 +255,6 @@ struct mem_cgroup {
 	struct memcg_cgwb_frn cgwb_frn[MEMCG_CGWB_FRN_CNT];
 #endif
 
-	/* List of events which userspace want to receive */
-	struct list_head event_list;
-	spinlock_t event_list_lock;
-
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 	struct deferred_split deferred_split_queue;
 #endif
@@ -313,6 +264,58 @@ struct mem_cgroup {
 	struct lru_gen_mm_list mm_list;
 #endif
 
+#ifdef CONFIG_MEMCG_V1
+	/* Legacy consumer-oriented counters */
+	struct page_counter kmem;		/* v1 only */
+	struct page_counter tcpmem;		/* v1 only */
+
+	unsigned long soft_limit;
+
+	/* protected by memcg_oom_lock */
+	bool oom_lock;
+	int under_oom;
+
+	/* OOM-Killer disable */
+	int oom_kill_disable;
+
+	/* protect arrays of thresholds */
+	struct mutex thresholds_lock;
+
+	/* thresholds for memory usage. RCU-protected */
+	struct mem_cgroup_thresholds thresholds;
+
+	/* thresholds for mem+swap usage. RCU-protected */
+	struct mem_cgroup_thresholds memsw_thresholds;
+
+	/* For oom notifier event fd */
+	struct list_head oom_notify;
+
+	/*
+	 * Should we move charges of a task when a task is moved into this
+	 * mem_cgroup ? And what type of charges should we move ?
+	 */
+	unsigned long move_charge_at_immigrate;
+	/* taken only while moving_account > 0 */
+	spinlock_t move_lock;
+	unsigned long move_lock_flags;
+
+	/* Legacy tcp memory accounting */
+	bool tcpmem_active;
+	int tcpmem_pressure;
+
+	CACHELINE_PADDING(_pad2_);
+
+	/*
+	 * set > 0 if pages under this cgroup are moving to other cgroup.
+	 */
+	atomic_t moving_account;
+	struct task_struct *move_lock_task;
+
+	/* List of events which userspace want to receive */
+	struct list_head event_list;
+	spinlock_t event_list_lock;
+#endif /* CONFIG_MEMCG_V1 */
+
 	struct mem_cgroup_per_node *nodeinfo[];
 };