mm: memcontrol: add the missing numa_stat interface for cgroup v2

In the cgroup v1, we have a numa_stat interface.  This is useful for
providing visibility into the numa locality information within an memcg
since the pages are allowed to be allocated from any physical node.  One
of the use cases is evaluating application performance by combining this
information with the application's CPU allocation.  But the cgroup v2 does
not.  So this patch adds the missing information.

Suggested-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Link: https://lkml.kernel.org/r/20200916100030.71698-2-songmuchun@bytedance.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 110 insertions, 60 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index a0bfc92804b7..e9fa32a943c5 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1448,6 +1448,70 @@ static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg)
 	return false;
 }
 
+struct memory_stat {
+	const char *name;
+	unsigned int ratio;
+	unsigned int idx;
+};
+
+static struct memory_stat memory_stats[] = {
+	{ "anon", PAGE_SIZE, NR_ANON_MAPPED },
+	{ "file", PAGE_SIZE, NR_FILE_PAGES },
+	{ "kernel_stack", 1024, NR_KERNEL_STACK_KB },
+	{ "percpu", 1, MEMCG_PERCPU_B },
+	{ "sock", PAGE_SIZE, MEMCG_SOCK },
+	{ "shmem", PAGE_SIZE, NR_SHMEM },
+	{ "file_mapped", PAGE_SIZE, NR_FILE_MAPPED },
+	{ "file_dirty", PAGE_SIZE, NR_FILE_DIRTY },
+	{ "file_writeback", PAGE_SIZE, NR_WRITEBACK },
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+	/*
+	 * The ratio will be initialized in memory_stats_init(). Because
+	 * on some architectures, the macro of HPAGE_PMD_SIZE is not
+	 * constant(e.g. powerpc).
+	 */
+	{ "anon_thp", 0, NR_ANON_THPS },
+#endif
+	{ "inactive_anon", PAGE_SIZE, NR_INACTIVE_ANON },
+	{ "active_anon", PAGE_SIZE, NR_ACTIVE_ANON },
+	{ "inactive_file", PAGE_SIZE, NR_INACTIVE_FILE },
+	{ "active_file", PAGE_SIZE, NR_ACTIVE_FILE },
+	{ "unevictable", PAGE_SIZE, NR_UNEVICTABLE },
+
+	/*
+	 * Note: The slab_reclaimable and slab_unreclaimable must be
+	 * together and slab_reclaimable must be in front.
+	 */
+	{ "slab_reclaimable", 1, NR_SLAB_RECLAIMABLE_B },
+	{ "slab_unreclaimable", 1, NR_SLAB_UNRECLAIMABLE_B },
+
+	/* The memory events */
+	{ "workingset_refault_anon", 1, WORKINGSET_REFAULT_ANON },
+	{ "workingset_refault_file", 1, WORKINGSET_REFAULT_FILE },
+	{ "workingset_activate_anon", 1, WORKINGSET_ACTIVATE_ANON },
+	{ "workingset_activate_file", 1, WORKINGSET_ACTIVATE_FILE },
+	{ "workingset_restore_anon", 1, WORKINGSET_RESTORE_ANON },
+	{ "workingset_restore_file", 1, WORKINGSET_RESTORE_FILE },
+	{ "workingset_nodereclaim", 1, WORKINGSET_NODERECLAIM },
+};
+
+static int __init memory_stats_init(void)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(memory_stats); i++) {
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+		if (memory_stats[i].idx == NR_ANON_THPS)
+			memory_stats[i].ratio = HPAGE_PMD_SIZE;
+#endif
+		VM_BUG_ON(!memory_stats[i].ratio);
+		VM_BUG_ON(memory_stats[i].idx >= MEMCG_NR_STAT);
+	}
+
+	return 0;
+}
+pure_initcall(memory_stats_init);
+
 static char *memory_stat_format(struct mem_cgroup *memcg)
 {
 	struct seq_buf s;
@@ -1468,52 +1532,19 @@ static char *memory_stat_format(struct mem_cgroup *memcg)
 	 * Current memory state:
 	 */
 
-	seq_buf_printf(&s, "anon %llu\n",
-		       (u64)memcg_page_state(memcg, NR_ANON_MAPPED) *
-		       PAGE_SIZE);
-	seq_buf_printf(&s, "file %llu\n",
-		       (u64)memcg_page_state(memcg, NR_FILE_PAGES) *
-		       PAGE_SIZE);
-	seq_buf_printf(&s, "kernel_stack %llu\n",
-		       (u64)memcg_page_state(memcg, NR_KERNEL_STACK_KB) *
-		       1024);
-	seq_buf_printf(&s, "slab %llu\n",
-		       (u64)(memcg_page_state(memcg, NR_SLAB_RECLAIMABLE_B) +
-			     memcg_page_state(memcg, NR_SLAB_UNRECLAIMABLE_B)));
-	seq_buf_printf(&s, "percpu %llu\n",
-		       (u64)memcg_page_state(memcg, MEMCG_PERCPU_B));
-	seq_buf_printf(&s, "sock %llu\n",
-		       (u64)memcg_page_state(memcg, MEMCG_SOCK) *
-		       PAGE_SIZE);
-
-	seq_buf_printf(&s, "shmem %llu\n",
-		       (u64)memcg_page_state(memcg, NR_SHMEM) *
-		       PAGE_SIZE);
-	seq_buf_printf(&s, "file_mapped %llu\n",
-		       (u64)memcg_page_state(memcg, NR_FILE_MAPPED) *
-		       PAGE_SIZE);
-	seq_buf_printf(&s, "file_dirty %llu\n",
-		       (u64)memcg_page_state(memcg, NR_FILE_DIRTY) *
-		       PAGE_SIZE);
-	seq_buf_printf(&s, "file_writeback %llu\n",
-		       (u64)memcg_page_state(memcg, NR_WRITEBACK) *
-		       PAGE_SIZE);
-
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	seq_buf_printf(&s, "anon_thp %llu\n",
-		       (u64)memcg_page_state(memcg, NR_ANON_THPS) *
-		       HPAGE_PMD_SIZE);
-#endif
+	for (i = 0; i < ARRAY_SIZE(memory_stats); i++) {
+		u64 size;
 
-	for (i = 0; i < NR_LRU_LISTS; i++)
-		seq_buf_printf(&s, "%s %llu\n", lru_list_name(i),
-			       (u64)memcg_page_state(memcg, NR_LRU_BASE + i) *
-			       PAGE_SIZE);
+		size = memcg_page_state(memcg, memory_stats[i].idx);
+		size *= memory_stats[i].ratio;
+		seq_buf_printf(&s, "%s %llu\n", memory_stats[i].name, size);
 
-	seq_buf_printf(&s, "slab_reclaimable %llu\n",
-		       (u64)memcg_page_state(memcg, NR_SLAB_RECLAIMABLE_B));
-	seq_buf_printf(&s, "slab_unreclaimable %llu\n",
-		       (u64)memcg_page_state(memcg, NR_SLAB_UNRECLAIMABLE_B));
+		if (unlikely(memory_stats[i].idx == NR_SLAB_UNRECLAIMABLE_B)) {
+			size = memcg_page_state(memcg, NR_SLAB_RECLAIMABLE_B) +
+			       memcg_page_state(memcg, NR_SLAB_UNRECLAIMABLE_B);
+			seq_buf_printf(&s, "slab %llu\n", size);
+		}
+	}
 
 	/* Accumulated memory events */
 
@@ -1521,22 +1552,6 @@ static char *memory_stat_format(struct mem_cgroup *memcg)
 		       memcg_events(memcg, PGFAULT));
 	seq_buf_printf(&s, "%s %lu\n", vm_event_name(PGMAJFAULT),
 		       memcg_events(memcg, PGMAJFAULT));
-
-	seq_buf_printf(&s, "workingset_refault_anon %lu\n",
-		       memcg_page_state(memcg, WORKINGSET_REFAULT_ANON));
-	seq_buf_printf(&s, "workingset_refault_file %lu\n",
-		       memcg_page_state(memcg, WORKINGSET_REFAULT_FILE));
-	seq_buf_printf(&s, "workingset_activate_anon %lu\n",
-		       memcg_page_state(memcg, WORKINGSET_ACTIVATE_ANON));
-	seq_buf_printf(&s, "workingset_activate_file %lu\n",
-		       memcg_page_state(memcg, WORKINGSET_ACTIVATE_FILE));
-	seq_buf_printf(&s, "workingset_restore_anon %lu\n",
-		       memcg_page_state(memcg, WORKINGSET_RESTORE_ANON));
-	seq_buf_printf(&s, "workingset_restore_file %lu\n",
-		       memcg_page_state(memcg, WORKINGSET_RESTORE_FILE));
-	seq_buf_printf(&s, "workingset_nodereclaim %lu\n",
-		       memcg_page_state(memcg, WORKINGSET_NODERECLAIM));
-
 	seq_buf_printf(&s, "%s %lu\n",  vm_event_name(PGREFILL),
 		       memcg_events(memcg, PGREFILL));
 	seq_buf_printf(&s, "pgscan %lu\n",
@@ -6374,6 +6389,35 @@ static int memory_stat_show(struct seq_file *m, void *v)
 	return 0;
 }
 
+#ifdef CONFIG_NUMA
+static int memory_numa_stat_show(struct seq_file *m, void *v)
+{
+	int i;
+	struct mem_cgroup *memcg = mem_cgroup_from_seq(m);
+
+	for (i = 0; i < ARRAY_SIZE(memory_stats); i++) {
+		int nid;
+
+		if (memory_stats[i].idx >= NR_VM_NODE_STAT_ITEMS)
+			continue;
+
+		seq_printf(m, "%s", memory_stats[i].name);
+		for_each_node_state(nid, N_MEMORY) {
+			u64 size;
+			struct lruvec *lruvec;
+
+			lruvec = mem_cgroup_lruvec(memcg, NODE_DATA(nid));
+			size = lruvec_page_state(lruvec, memory_stats[i].idx);
+			size *= memory_stats[i].ratio;
+			seq_printf(m, " N%d=%llu", nid, size);
+		}
+		seq_putc(m, '\n');
+	}
+
+	return 0;
+}
+#endif
+
 static int memory_oom_group_show(struct seq_file *m, void *v)
 {
 	struct mem_cgroup *memcg = mem_cgroup_from_seq(m);
@@ -6451,6 +6495,12 @@ static struct cftype memory_files[] = {
 		.name = "stat",
 		.seq_show = memory_stat_show,
 	},
+#ifdef CONFIG_NUMA
+	{
+		.name = "numa_stat",
+		.seq_show = memory_numa_stat_show,
+	},
+#endif
 	{
 		.name = "oom.group",
 		.flags = CFTYPE_NOT_ON_ROOT | CFTYPE_NS_DELEGATABLE,