From 772616b031f06e05846488b01dab46a7c832da13 Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Tue, 11 Aug 2020 18:30:21 -0700 Subject: mm: memcg/percpu: per-memcg percpu memory statistics MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Percpu memory can represent a noticeable chunk of the total memory consumption, especially on big machines with many CPUs. Let's track percpu memory usage for each memcg and display it in memory.stat. A percpu allocation is usually scattered over multiple pages (and nodes), and can be significantly smaller than a page. So let's add a byte-sized counter on the memcg level: MEMCG_PERCPU_B. Byte-sized vmstat infra created for slabs can be perfectly reused for percpu case. [guro@fb.com: v3] Link: http://lkml.kernel.org/r/20200623184515.4132564-4-guro@fb.com Signed-off-by: Roman Gushchin Signed-off-by: Andrew Morton Reviewed-by: Shakeel Butt Acked-by: Dennis Zhou Acked-by: Johannes Weiner Cc: Christoph Lameter Cc: David Rientjes Cc: Joonsoo Kim Cc: Mel Gorman Cc: Michal Hocko Cc: Pekka Enberg Cc: Tejun Heo Cc: Tobin C. Harding Cc: Vlastimil Babka Cc: Waiman Long Cc: Bixuan Cui Cc: Michal Koutný Cc: Stephen Rothwell Link: http://lkml.kernel.org/r/20200608230819.832349-4-guro@fb.com Signed-off-by: Linus Torvalds --- mm/percpu.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'mm/percpu.c') diff --git a/mm/percpu.c b/mm/percpu.c index dc1a213293aa..f4709629e6de 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -1610,6 +1610,11 @@ static void pcpu_memcg_post_alloc_hook(struct obj_cgroup *objcg, if (chunk) { chunk->obj_cgroups[off >> PCPU_MIN_ALLOC_SHIFT] = objcg; + + rcu_read_lock(); + mod_memcg_state(obj_cgroup_memcg(objcg), MEMCG_PERCPU_B, + size * num_possible_cpus()); + rcu_read_unlock(); } else { obj_cgroup_uncharge(objcg, size * num_possible_cpus()); obj_cgroup_put(objcg); @@ -1628,6 +1633,11 @@ static void pcpu_memcg_free_hook(struct pcpu_chunk *chunk, int off, size_t size) obj_cgroup_uncharge(objcg, size * num_possible_cpus()); + rcu_read_lock(); + mod_memcg_state(obj_cgroup_memcg(objcg), MEMCG_PERCPU_B, + -(size * num_possible_cpus())); + rcu_read_unlock(); + obj_cgroup_put(objcg); } -- cgit v1.2.3-58-ga151