[PATCH 2/3] mm: memcontrol: report slab usage in cgroup2 memory.stat
From: Vladimir Davydov
Date: Thu Feb 04 2016 - 08:03:57 EST
Show how much memory is used for storing reclaimable and unreclaimable
in-kernel data structures allocated from slab caches.
Signed-off-by: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx>
---
Documentation/cgroup-v2.txt | 15 +++++++++++++++
include/linux/memcontrol.h | 21 +++++++++++++++++++++
mm/memcontrol.c | 8 ++++++++
mm/slab.c | 8 +++++---
mm/slab.h | 30 ++++++++++++++++++++++++++++--
mm/slub.c | 3 ++-
6 files changed, 79 insertions(+), 6 deletions(-)
diff --git a/Documentation/cgroup-v2.txt b/Documentation/cgroup-v2.txt
index ff49cf901148..e4e0c1d78cee 100644
--- a/Documentation/cgroup-v2.txt
+++ b/Documentation/cgroup-v2.txt
@@ -843,6 +843,11 @@ PAGE_SIZE multiple when read back.
Amount of memory used to cache filesystem data,
including tmpfs and shared memory.
+ slab
+
+ Amount of memory used for storing in-kernel data
+ structures.
+
sock
Amount of memory used in network transmission buffers
@@ -871,6 +876,16 @@ PAGE_SIZE multiple when read back.
on the internal memory management lists used by the
page reclaim algorithm
+ slab_reclaimable
+
+ Part of "slab" that might be reclaimed, such as
+ dentries and inodes.
+
+ slab_unreclaimable
+
+ Part of "slab" that cannot be reclaimed on memory
+ pressure.
+
pgfault
Total number of page faults incurred
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index f0c4bec6565b..e7af4834ffea 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -53,6 +53,8 @@ enum mem_cgroup_stat_index {
MEM_CGROUP_STAT_NSTATS,
/* default hierarchy stats */
MEMCG_SOCK = MEM_CGROUP_STAT_NSTATS,
+ MEMCG_SLAB_RECLAIMABLE,
+ MEMCG_SLAB_UNRECLAIMABLE,
MEMCG_NR_STAT,
};
@@ -883,6 +885,20 @@ static __always_inline void memcg_kmem_put_cache(struct kmem_cache *cachep)
if (memcg_kmem_enabled())
__memcg_kmem_put_cache(cachep);
}
+
+/**
+ * memcg_kmem_update_page_stat - update kmem page state statistics
+ * @page: the page
+ * @idx: page state item to account
+ * @val: number of pages (positive or negative)
+ */
+static inline void memcg_kmem_update_page_stat(struct page *page,
+ enum mem_cgroup_stat_index idx, int val)
+{
+ if (memcg_kmem_enabled() && page->mem_cgroup)
+ this_cpu_add(page->mem_cgroup->stat->count[idx], val);
+}
+
#else
#define for_each_memcg_cache_index(_idx) \
for (; NULL; )
@@ -928,6 +944,11 @@ memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp)
static inline void memcg_kmem_put_cache(struct kmem_cache *cachep)
{
}
+
+static inline void memcg_kmem_update_page_stat(struct page *page,
+ enum mem_cgroup_stat_index idx, int val)
+{
+}
#endif /* CONFIG_MEMCG && !CONFIG_SLOB */
#endif /* _LINUX_MEMCONTROL_H */
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 606dda49e671..b198ed5a8928 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5100,6 +5100,9 @@ static int memory_stat_show(struct seq_file *m, void *v)
(u64)stat[MEM_CGROUP_STAT_RSS] * PAGE_SIZE);
seq_printf(m, "file %llu\n",
(u64)stat[MEM_CGROUP_STAT_CACHE] * PAGE_SIZE);
+ seq_printf(m, "slab %llu\n",
+ (u64)(stat[MEMCG_SLAB_RECLAIMABLE] +
+ stat[MEMCG_SLAB_UNRECLAIMABLE]) * PAGE_SIZE);
seq_printf(m, "sock %llu\n",
(u64)stat[MEMCG_SOCK] * PAGE_SIZE);
@@ -5120,6 +5123,11 @@ static int memory_stat_show(struct seq_file *m, void *v)
mem_cgroup_lru_names[i], (u64)val * PAGE_SIZE);
}
+ seq_printf(m, "slab_reclaimable %llu\n",
+ (u64)stat[MEMCG_SLAB_RECLAIMABLE] * PAGE_SIZE);
+ seq_printf(m, "slab_unreclaimable %llu\n",
+ (u64)stat[MEMCG_SLAB_UNRECLAIMABLE] * PAGE_SIZE);
+
/* Accumulated memory events */
seq_printf(m, "pgfault %lu\n",
diff --git a/mm/slab.c b/mm/slab.c
index ff6526e56e6a..5b1c58206143 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1569,9 +1569,10 @@ static struct page *kmem_getpages(struct kmem_cache *cachep, gfp_t flags,
*/
static void kmem_freepages(struct kmem_cache *cachep, struct page *page)
{
- const unsigned long nr_freed = (1 << cachep->gfporder);
+ int order = cachep->gfporder;
+ unsigned long nr_freed = (1 << order);
- kmemcheck_free_shadow(page, cachep->gfporder);
+ kmemcheck_free_shadow(page, order);
if (cachep->flags & SLAB_RECLAIM_ACCOUNT)
sub_zone_page_state(page_zone(page),
@@ -1588,7 +1589,8 @@ static void kmem_freepages(struct kmem_cache *cachep, struct page *page)
if (current->reclaim_state)
current->reclaim_state->reclaimed_slab += nr_freed;
- __free_kmem_pages(page, cachep->gfporder);
+ memcg_uncharge_slab(page, order, cachep);
+ __free_pages(page, order);
}
static void kmem_rcu_free(struct rcu_head *head)
diff --git a/mm/slab.h b/mm/slab.h
index 43f89f33f9ad..124379603634 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -245,12 +245,33 @@ static __always_inline int memcg_charge_slab(struct page *page,
gfp_t gfp, int order,
struct kmem_cache *s)
{
+ int ret;
+
if (!memcg_kmem_enabled())
return 0;
if (is_root_cache(s))
return 0;
- return __memcg_kmem_charge_memcg(page, gfp, order,
- s->memcg_params.memcg);
+
+ ret = __memcg_kmem_charge_memcg(page, gfp, order,
+ s->memcg_params.memcg);
+ if (ret)
+ return ret;
+
+ memcg_kmem_update_page_stat(page,
+ (s->flags & SLAB_RECLAIM_ACCOUNT) ?
+ MEMCG_SLAB_RECLAIMABLE : MEMCG_SLAB_UNRECLAIMABLE,
+ 1 << order);
+ return 0;
+}
+
+static __always_inline void memcg_uncharge_slab(struct page *page, int order,
+ struct kmem_cache *s)
+{
+ memcg_kmem_update_page_stat(page,
+ (s->flags & SLAB_RECLAIM_ACCOUNT) ?
+ MEMCG_SLAB_RECLAIMABLE : MEMCG_SLAB_UNRECLAIMABLE,
+ -(1 << order));
+ memcg_kmem_uncharge(page, order);
}
extern void slab_init_memcg_params(struct kmem_cache *);
@@ -293,6 +314,11 @@ static inline int memcg_charge_slab(struct page *page, gfp_t gfp, int order,
return 0;
}
+static inline void memcg_uncharge_slab(struct page *page, int order,
+ struct kmem_cache *s)
+{
+}
+
static inline void slab_init_memcg_params(struct kmem_cache *s)
{
}
diff --git a/mm/slub.c b/mm/slub.c
index 7d4da68f1291..4270cc774380 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1474,7 +1474,8 @@ static void __free_slab(struct kmem_cache *s, struct page *page)
page_mapcount_reset(page);
if (current->reclaim_state)
current->reclaim_state->reclaimed_slab += pages;
- __free_kmem_pages(page, order);
+ memcg_uncharge_slab(page, order, s);
+ __free_pages(page, order);
}
#define need_reserve_slab_rcu \
--
2.1.4