memcg: aggregate memcg cache values in slabinfo

When we create caches in memcgs, we need to display their usage
information somewhere.  We'll adopt a scheme similar to /proc/meminfo,
with aggregate totals shown in the global file, and per-group information
stored in the group itself.

For the time being, only reads are allowed in the per-group cache.

Signed-off-by: Glauber Costa <glommer@parallels.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Frederic Weisbecker <fweisbec@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: JoonSoo Kim <js1304@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Rik van Riel <riel@redhat.com>
Cc: Suleiman Souhlal <suleiman@google.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Glauber Costa 2012-12-18 14:23:01 -08:00 committed by Linus Torvalds
parent 2293315293
commit 749c54151a
5 changed files with 108 additions and 5 deletions

View File

@ -420,6 +420,11 @@ static inline void sock_release_memcg(struct sock *sk)
#ifdef CONFIG_MEMCG_KMEM
extern struct static_key memcg_kmem_enabled_key;
extern int memcg_limited_groups_array_size;
#define for_each_memcg_cache_index(_idx) \
for ((_idx) = 0; i < memcg_limited_groups_array_size; (_idx)++)
static inline bool memcg_kmem_enabled(void)
{
return static_key_false(&memcg_kmem_enabled_key);
@ -557,6 +562,9 @@ memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp)
return __memcg_kmem_get_cache(cachep, gfp);
}
#else
#define for_each_memcg_cache_index(_idx) \
for (; NULL; )
static inline bool memcg_kmem_enabled(void)
{
return false;

View File

@ -220,6 +220,10 @@ struct memcg_cache_params {
int memcg_update_all_caches(int num_memcgs);
struct seq_file;
int cache_show(struct kmem_cache *s, struct seq_file *m);
void print_slabinfo_header(struct seq_file *m);
/*
* Common kmalloc functions provided by all allocators
*/

View File

@ -572,7 +572,8 @@ static void disarm_sock_keys(struct mem_cgroup *memcg)
* increase it.
*/
static DEFINE_IDA(kmem_limited_groups);
static int memcg_limited_groups_array_size;
int memcg_limited_groups_array_size;
/*
* MIN_SIZE is different than 1, because we would like to avoid going through
* the alloc/free process all the time. In a small machine, 4 kmem-limited
@ -2794,6 +2795,27 @@ static struct kmem_cache *memcg_params_to_cache(struct memcg_cache_params *p)
return cachep->memcg_params->memcg_caches[memcg_cache_id(p->memcg)];
}
#ifdef CONFIG_SLABINFO
static int mem_cgroup_slabinfo_read(struct cgroup *cont, struct cftype *cft,
struct seq_file *m)
{
struct mem_cgroup *memcg = mem_cgroup_from_cont(cont);
struct memcg_cache_params *params;
if (!memcg_can_account_kmem(memcg))
return -EIO;
print_slabinfo_header(m);
mutex_lock(&memcg->slab_caches_mutex);
list_for_each_entry(params, &memcg->memcg_slab_caches, list)
cache_show(memcg_params_to_cache(params), m);
mutex_unlock(&memcg->slab_caches_mutex);
return 0;
}
#endif
static int memcg_charge_kmem(struct mem_cgroup *memcg, gfp_t gfp, u64 size)
{
struct res_counter *fail_res;
@ -5822,6 +5844,12 @@ static struct cftype mem_cgroup_files[] = {
.trigger = mem_cgroup_reset,
.read = mem_cgroup_read,
},
#ifdef CONFIG_SLABINFO
{
.name = "kmem.slabinfo",
.read_seq_string = mem_cgroup_slabinfo_read,
},
#endif
#endif
{ }, /* terminate */
};

View File

@ -138,6 +138,23 @@ static inline bool slab_equal_or_root(struct kmem_cache *s,
return (p == s) ||
(s->memcg_params && (p == s->memcg_params->root_cache));
}
/*
* We use suffixes to the name in memcg because we can't have caches
* created in the system with the same name. But when we print them
* locally, better refer to them with the base name
*/
static inline const char *cache_name(struct kmem_cache *s)
{
if (!is_root_cache(s))
return s->memcg_params->root_cache->name;
return s->name;
}
static inline struct kmem_cache *cache_from_memcg(struct kmem_cache *s, int idx)
{
return s->memcg_params->memcg_caches[idx];
}
#else
static inline bool is_root_cache(struct kmem_cache *s)
{
@ -163,6 +180,16 @@ static inline bool slab_equal_or_root(struct kmem_cache *s,
{
return true;
}
static inline const char *cache_name(struct kmem_cache *s)
{
return s->name;
}
static inline struct kmem_cache *cache_from_memcg(struct kmem_cache *s, int idx)
{
return NULL;
}
#endif
static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)

View File

@ -322,7 +322,7 @@ struct kmem_cache *__init create_kmalloc_cache(const char *name, size_t size,
#ifdef CONFIG_SLABINFO
static void print_slabinfo_header(struct seq_file *m)
void print_slabinfo_header(struct seq_file *m)
{
/*
* Output format version, so at least we can change it
@ -366,16 +366,43 @@ static void s_stop(struct seq_file *m, void *p)
mutex_unlock(&slab_mutex);
}
static int s_show(struct seq_file *m, void *p)
static void
memcg_accumulate_slabinfo(struct kmem_cache *s, struct slabinfo *info)
{
struct kmem_cache *c;
struct slabinfo sinfo;
int i;
if (!is_root_cache(s))
return;
for_each_memcg_cache_index(i) {
c = cache_from_memcg(s, i);
if (!c)
continue;
memset(&sinfo, 0, sizeof(sinfo));
get_slabinfo(c, &sinfo);
info->active_slabs += sinfo.active_slabs;
info->num_slabs += sinfo.num_slabs;
info->shared_avail += sinfo.shared_avail;
info->active_objs += sinfo.active_objs;
info->num_objs += sinfo.num_objs;
}
}
int cache_show(struct kmem_cache *s, struct seq_file *m)
{
struct kmem_cache *s = list_entry(p, struct kmem_cache, list);
struct slabinfo sinfo;
memset(&sinfo, 0, sizeof(sinfo));
get_slabinfo(s, &sinfo);
memcg_accumulate_slabinfo(s, &sinfo);
seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d",
s->name, sinfo.active_objs, sinfo.num_objs, s->size,
cache_name(s), sinfo.active_objs, sinfo.num_objs, s->size,
sinfo.objects_per_slab, (1 << sinfo.cache_order));
seq_printf(m, " : tunables %4u %4u %4u",
@ -387,6 +414,15 @@ static int s_show(struct seq_file *m, void *p)
return 0;
}
static int s_show(struct seq_file *m, void *p)
{
struct kmem_cache *s = list_entry(p, struct kmem_cache, list);
if (!is_root_cache(s))
return 0;
return cache_show(s, m);
}
/*
* slabinfo_op - iterator that generates /proc/slabinfo
*