alinux: mm, memcg: add kconfig MEMSLI

to #26424368

This introduces the new bool kconfig MEMSLI, determining whether the
memsli (memory latency histogram) feature should be built-in or not.
Signed-off-by: NXu Yu <xuyu@linux.alibaba.com>
Reviewed-by: NYang Shi <yang.shi@linux.alibaba.com>
Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>

include/linux/memcontrol.h

@@ -935,10 +935,6 @@ static inline bool is_wmark_ok(struct mem_cgroup *memcg, bool high)
 int memcg_get_wmark_min_adj(struct task_struct *curr);
 void memcg_check_wmark_min_adj(struct task_struct *curr,
 		struct alloc_context *ac);
-
-extern void memcg_lat_stat_update(enum mem_lat_stat_item sidx, u64 duration);
-extern void memcg_lat_stat_start(u64 *start);
-extern u64 memcg_lat_stat_end(u64 start);
 #else /* CONFIG_MEMCG */
 
 #define MEM_CGROUP_ID_SHIFT	0
@@ -1289,7 +1285,13 @@ static inline void memcg_check_wmark_min_adj(struct task_struct *curr,
 		struct alloc_context *ac)
 {
 }
+#endif /* CONFIG_MEMCG */
 
+#ifdef CONFIG_MEMSLI
+extern void memcg_lat_stat_update(enum mem_lat_stat_item sidx, u64 duration);
+extern void memcg_lat_stat_start(u64 *start);
+extern u64 memcg_lat_stat_end(u64 start);
+#else
 static inline void memcg_lat_stat_update(enum mem_lat_stat_item sidx,
 					 u64 duration)
 {
@@ -1303,7 +1305,7 @@ static inline u64 memcg_lat_stat_end(u64 start)
 {
 	return 0;
 }
-#endif /* CONFIG_MEMCG */
+#endif /* CONFIG_MEMSLI */
 
 /* idx can be of type enum memcg_stat_item or node_stat_item */
 static inline void __inc_memcg_state(struct mem_cgroup *memcg,

mm/Kconfig

@@ -786,4 +786,13 @@ config KIDLED
 
 	  See Documentation/vm/kidled.rst for more details.
 
+config MEMSLI
+	bool "Support memory latency histogram, a.k.a, memsli"
+	depends on MEMCG
+	default Y
+	help
+	  This probes and calculates various kinds of memory latency, and then
+	  groups into the corresponding latency histogram in every memory
+	  cgroup, respectively.
+
 endmenu

mm/memcontrol.c

@@ -4523,6 +4523,7 @@ void memcg_check_wmark_min_adj(struct task_struct *curr,
 	}
 }
 
+#ifdef CONFIG_MEMSLI
 #define MEMCG_LAT_STAT_SMP_WRITE(name, sidx)				\
 static void smp_write_##name(void *info)				\
 {									\
@@ -4663,6 +4664,7 @@ u64 memcg_lat_stat_end(u64 start)
 	else
 		return 0;
 }
+#endif /* CONFIG_MEMSLI */
 
 static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap)
 {
@@ -5563,6 +5565,7 @@ static struct cftype mem_cgroup_legacy_files[] = {
 		.seq_show = memory_wmark_min_adj_show,
 		.write = memory_wmark_min_adj_write,
 	},
+#ifdef CONFIG_MEMSLI
 	{
 		.name = "direct_reclaim_global_latency",
 		.private = MEM_LAT_GLOBAL_DIRECT_RECLAIM,
@@ -5599,6 +5602,7 @@ static struct cftype mem_cgroup_legacy_files[] = {
 		.write_u64 = memcg_lat_stat_write,
 		.seq_show =  memcg_lat_stat_show,
 	},
+#endif /* CONFIG_MEMSLI */
 	{
 		.name = "force_empty",
 		.write = mem_cgroup_force_empty_write,
@@ -7777,6 +7781,7 @@ static int __init enable_cgroup_writeback_v1(char *s)
 __setup("cgwb_v1", enable_cgroup_writeback_v1);
 #endif
 
+#ifdef CONFIG_MEMSLI
 static int memsli_enabled_show(struct seq_file *m, void *v)
 {
 	seq_printf(m, "%d\n", !static_key_enabled(&cgroup_memory_nosli));
@@ -7826,6 +7831,7 @@ static const struct file_operations memsli_enabled_fops = {
 	.llseek         = seq_lseek,
 	.release        = single_release,
 };
+#endif /* CONFIG_MEMSLI */
 
 /*
  * subsys_initcall() for memory controller.
@@ -7847,6 +7853,7 @@ static int __init mem_cgroup_init(void)
 	if (!memcg_wmark_wq)
 		return -ENOMEM;
 
+#ifdef CONFIG_MEMSLI
 	memsli_dir = proc_mkdir("memsli", NULL);
 	if (!memsli_dir)
 		return -ENOMEM;
@@ -7857,6 +7864,7 @@ static int __init mem_cgroup_init(void)
 		remove_proc_entry("memsli", NULL);
 		return -ENOMEM;
 	}
+#endif /* CONFIG_MEMSLI */
 
 #ifdef CONFIG_MEMCG_KMEM
 	/*