From 127424c86bb6cb87f0b563d9fdcfbbaf3c86ecec Mon Sep 17 00:00:00 2001
From: Johannes Weiner
Date: Wed, 20 Jan 2016 15:02:32 -0800
Subject: mm: memcontrol: move kmem accounting code to CONFIG_MEMCG

The cgroup2 memory controller will account important in-kernel memory
consumers per default.  Move all necessary components to CONFIG_MEMCG.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 mm/memcontrol.c | 69 ++++++++++++++++++++++++++++++++++-----------------------
 1 file changed, 41 insertions(+), 28 deletions(-)

(limited to 'mm/memcontrol.c')

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 7f8219b58e0c..fe51d5e61389 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -297,7 +297,7 @@ static inline struct mem_cgroup *mem_cgroup_from_id(unsigned short id)
 	return mem_cgroup_from_css(css);
 }
 
-#ifdef CONFIG_MEMCG_KMEM
+#ifndef CONFIG_SLOB
 /*
  * This will be the memcg's index in each cache's ->memcg_params.memcg_caches.
  * The main reason for not using cgroup id for this:
@@ -349,7 +349,7 @@ void memcg_put_cache_ids(void)
 DEFINE_STATIC_KEY_FALSE(memcg_kmem_enabled_key);
 EXPORT_SYMBOL(memcg_kmem_enabled_key);
 
-#endif /* CONFIG_MEMCG_KMEM */
+#endif /* !CONFIG_SLOB */
 
 static struct mem_cgroup_per_zone *
 mem_cgroup_zone_zoneinfo(struct mem_cgroup *memcg, struct zone *zone)
@@ -2203,7 +2203,7 @@ static void commit_charge(struct page *page, struct mem_cgroup *memcg,
 		unlock_page_lru(page, isolated);
 }
 
-#ifdef CONFIG_MEMCG_KMEM
+#ifndef CONFIG_SLOB
 static int memcg_alloc_cache_id(void)
 {
 	int id, size;
@@ -2424,7 +2424,7 @@ void __memcg_kmem_uncharge(struct page *page, int order)
 	page->mem_cgroup = NULL;
 	css_put_many(&memcg->css, nr_pages);
 }
-#endif /* CONFIG_MEMCG_KMEM */
+#endif /* !CONFIG_SLOB */
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 
@@ -2860,7 +2860,7 @@ static u64 mem_cgroup_read_u64(struct cgroup_subsys_state *css,
 	}
 }
 
-#ifdef CONFIG_MEMCG_KMEM
+#ifndef CONFIG_SLOB
 static int memcg_online_kmem(struct mem_cgroup *memcg)
 {
 	int err = 0;
@@ -2908,24 +2908,6 @@ out:
 	return err;
 }
 
-static int memcg_update_kmem_limit(struct mem_cgroup *memcg,
-				   unsigned long limit)
-{
-	int ret;
-
-	mutex_lock(&memcg_limit_mutex);
-	/* Top-level cgroup doesn't propagate from root */
-	if (!memcg_kmem_online(memcg)) {
-		ret = memcg_online_kmem(memcg);
-		if (ret)
-			goto out;
-	}
-	ret = page_counter_limit(&memcg->kmem, limit);
-out:
-	mutex_unlock(&memcg_limit_mutex);
-	return ret;
-}
-
 static int memcg_propagate_kmem(struct mem_cgroup *memcg)
 {
 	int ret = 0;
@@ -3000,16 +2982,45 @@ static void memcg_free_kmem(struct mem_cgroup *memcg)
 	}
 }
 #else
+static int memcg_propagate_kmem(struct mem_cgroup *memcg)
+{
+	return 0;
+}
+static void memcg_offline_kmem(struct mem_cgroup *memcg)
+{
+}
+static void memcg_free_kmem(struct mem_cgroup *memcg)
+{
+}
+#endif /* !CONFIG_SLOB */
+
+#ifdef CONFIG_MEMCG_KMEM
 static int memcg_update_kmem_limit(struct mem_cgroup *memcg,
 				   unsigned long limit)
 {
-	return -EINVAL;
+	int ret;
+
+	mutex_lock(&memcg_limit_mutex);
+	/* Top-level cgroup doesn't propagate from root */
+	if (!memcg_kmem_online(memcg)) {
+		ret = memcg_online_kmem(memcg);
+		if (ret)
+			goto out;
+	}
+	ret = page_counter_limit(&memcg->kmem, limit);
+out:
+	mutex_unlock(&memcg_limit_mutex);
+	return ret;
 }
-static void memcg_offline_kmem(struct mem_cgroup *memcg)
+#else
+static int memcg_update_kmem_limit(struct mem_cgroup *memcg,
+				   unsigned long limit)
 {
+	return -EINVAL;
 }
 #endif /* CONFIG_MEMCG_KMEM */
 
+
 /*
  * The user of this function is...
  * RES_LIMIT.
@@ -4182,7 +4193,7 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css)
 	vmpressure_init(&memcg->vmpressure);
 	INIT_LIST_HEAD(&memcg->event_list);
 	spin_lock_init(&memcg->event_list_lock);
-#ifdef CONFIG_MEMCG_KMEM
+#ifndef CONFIG_SLOB
 	memcg->kmemcg_id = -1;
 #endif
 #ifdef CONFIG_CGROUP_WRITEBACK
@@ -4244,10 +4255,11 @@ mem_cgroup_css_online(struct cgroup_subsys_state *css)
 	}
 	mutex_unlock(&memcg_create_mutex);
 
-#ifdef CONFIG_MEMCG_KMEM
 	ret = memcg_propagate_kmem(memcg);
 	if (ret)
 		return ret;
+
+#ifdef CONFIG_MEMCG_KMEM
 	ret = tcp_init_cgroup(memcg);
 	if (ret)
 		return ret;
@@ -4308,8 +4320,9 @@ static void mem_cgroup_css_free(struct cgroup_subsys_state *css)
 		static_branch_dec(&memcg_sockets_enabled_key);
 #endif
 
-#ifdef CONFIG_MEMCG_KMEM
 	memcg_free_kmem(memcg);
+
+#ifdef CONFIG_MEMCG_KMEM
 	tcp_destroy_cgroup(memcg);
 #endif
 
-- 
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