From df21a9c904e7cb4eacc97c9278464600394660ba Mon Sep 17 00:00:00 2001
From: Glauber Costa <glommer@parallels.com>
Date: Tue, 18 Dec 2012 14:22:27 -0800
Subject: [PATCH] --- yaml --- r: 347016 b: refs/heads/master c:
 ba6c496ed834a37a26fc6fc87fc9aecb0fa0014d h: refs/heads/master v: v3

---
 [refs]                         |  2 +-
 trunk/include/linux/slab.h     | 24 ++++++++++++++++++++++++
 trunk/include/linux/slab_def.h |  3 +++
 trunk/include/linux/slub_def.h |  3 +++
 trunk/mm/slab.h                | 13 +++++++++++++
 5 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 9b37666e855d..615af2ea9dcc 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d5bdae7d59451b9d63303f7794ef32bb76ba6330
+refs/heads/master: ba6c496ed834a37a26fc6fc87fc9aecb0fa0014d
diff --git a/trunk/include/linux/slab.h b/trunk/include/linux/slab.h
index 743a10415122..00efba149222 100644
--- a/trunk/include/linux/slab.h
+++ b/trunk/include/linux/slab.h
@@ -176,6 +176,30 @@ void kmem_cache_free(struct kmem_cache *, void *);
 #define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
 #endif
 
+/*
+ * This is the main placeholder for memcg-related information in kmem caches.
+ * struct kmem_cache will hold a pointer to it, so the memory cost while
+ * disabled is 1 pointer. The runtime cost while enabled, gets bigger than it
+ * would otherwise be if that would be bundled in kmem_cache: we'll need an
+ * extra pointer chase. But the trade off clearly lays in favor of not
+ * penalizing non-users.
+ *
+ * Both the root cache and the child caches will have it. For the root cache,
+ * this will hold a dynamically allocated array large enough to hold
+ * information about the currently limited memcgs in the system.
+ *
+ * Child caches will hold extra metadata needed for its operation. Fields are:
+ *
+ * @memcg: pointer to the memcg this cache belongs to
+ */
+struct memcg_cache_params {
+	bool is_root_cache;
+	union {
+		struct kmem_cache *memcg_caches[0];
+		struct mem_cgroup *memcg;
+	};
+};
+
 /*
  * Common kmalloc functions provided by all allocators
  */
diff --git a/trunk/include/linux/slab_def.h b/trunk/include/linux/slab_def.h
index 45c0356fdc8c..8bb6e0eaf3c6 100644
--- a/trunk/include/linux/slab_def.h
+++ b/trunk/include/linux/slab_def.h
@@ -81,6 +81,9 @@ struct kmem_cache {
 	 */
 	int obj_offset;
 #endif /* CONFIG_DEBUG_SLAB */
+#ifdef CONFIG_MEMCG_KMEM
+	struct memcg_cache_params *memcg_params;
+#endif
 
 /* 6) per-cpu/per-node data, touched during every alloc/free */
 	/*
diff --git a/trunk/include/linux/slub_def.h b/trunk/include/linux/slub_def.h
index df448adb7283..961e72eab907 100644
--- a/trunk/include/linux/slub_def.h
+++ b/trunk/include/linux/slub_def.h
@@ -101,6 +101,9 @@ struct kmem_cache {
 #ifdef CONFIG_SYSFS
 	struct kobject kobj;	/* For sysfs */
 #endif
+#ifdef CONFIG_MEMCG_KMEM
+	struct memcg_cache_params *memcg_params;
+#endif
 
 #ifdef CONFIG_NUMA
 	/*
diff --git a/trunk/mm/slab.h b/trunk/mm/slab.h
index 1cb9c9ee0e6f..49e7a8b1d27e 100644
--- a/trunk/mm/slab.h
+++ b/trunk/mm/slab.h
@@ -100,4 +100,17 @@ void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo);
 void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s);
 ssize_t slabinfo_write(struct file *file, const char __user *buffer,
 		       size_t count, loff_t *ppos);
+
+#ifdef CONFIG_MEMCG_KMEM
+static inline bool is_root_cache(struct kmem_cache *s)
+{
+	return !s->memcg_params || s->memcg_params->is_root_cache;
+}
+#else
+static inline bool is_root_cache(struct kmem_cache *s)
+{
+	return true;
+}
+
+#endif
 #endif