The patch titled Subject: mm: memcontrol: fix memcg id ref counter on swap charge move has been removed from the -mm tree. Its filename was mm-memcontrol-fix-memcg-id-ref-counter-on-swap-charge-move.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx> Subject: mm: memcontrol: fix memcg id ref counter on swap charge move Since commit 73f576c04b941 swap entries do not pin memcg->css.refcnt directly. Instead, they pin memcg->id.ref. So we should adjust the reference counters accordingly when moving swap charges between cgroups. Fixes: 73f576c04b941 ("mm: memcontrol: fix cgroup creation failure after many small jobs") Link: http://lkml.kernel.org/r/9ce297c64954a42dc90b543bc76106c4a94f07e8.1470219853.git.vdavydov@xxxxxxxxxxxxx Signed-off-by: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> [3.19+] Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memcontrol.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) diff -puN mm/memcontrol.c~mm-memcontrol-fix-memcg-id-ref-counter-on-swap-charge-move mm/memcontrol.c --- a/mm/memcontrol.c~mm-memcontrol-fix-memcg-id-ref-counter-on-swap-charge-move +++ a/mm/memcontrol.c @@ -4077,9 +4077,9 @@ static struct cftype mem_cgroup_legacy_f static DEFINE_IDR(mem_cgroup_idr); -static void mem_cgroup_id_get(struct mem_cgroup *memcg) +static void mem_cgroup_id_get_many(struct mem_cgroup *memcg, unsigned int n) { - atomic_inc(&memcg->id.ref); + atomic_add(n, &memcg->id.ref); } static struct mem_cgroup *mem_cgroup_id_get_online(struct mem_cgroup *memcg) @@ -4100,9 +4100,9 @@ static struct mem_cgroup *mem_cgroup_id_ return memcg; } -static void mem_cgroup_id_put(struct mem_cgroup *memcg) +static void mem_cgroup_id_put_many(struct mem_cgroup *memcg, unsigned int n) { - if (atomic_dec_and_test(&memcg->id.ref)) { + if (atomic_sub_and_test(n, &memcg->id.ref)) { idr_remove(&mem_cgroup_idr, memcg->id.id); memcg->id.id = 0; @@ -4111,6 +4111,16 @@ static void mem_cgroup_id_put(struct mem } } +static inline void mem_cgroup_id_get(struct mem_cgroup *memcg) +{ + mem_cgroup_id_get_many(memcg, 1); +} + +static inline void mem_cgroup_id_put(struct mem_cgroup *memcg) +{ + mem_cgroup_id_put_many(memcg, 1); +} + /** * mem_cgroup_from_id - look up a memcg from a memcg id * @id: the memcg id to look up @@ -4745,6 +4755,8 @@ static void __mem_cgroup_clear_mc(void) if (!mem_cgroup_is_root(mc.from)) page_counter_uncharge(&mc.from->memsw, mc.moved_swap); + mem_cgroup_id_put_many(mc.from, mc.moved_swap); + /* * we charged both to->memory and to->memsw, so we * should uncharge to->memory. @@ -4752,9 +4764,9 @@ static void __mem_cgroup_clear_mc(void) if (!mem_cgroup_is_root(mc.to)) page_counter_uncharge(&mc.to->memory, mc.moved_swap); - css_put_many(&mc.from->css, mc.moved_swap); + mem_cgroup_id_get_many(mc.to, mc.moved_swap); + css_put_many(&mc.to->css, mc.moved_swap); - /* we've already done css_get(mc.to) */ mc.moved_swap = 0; } memcg_oom_recover(from); _ Patches currently in -mm which might be from vdavydov@xxxxxxxxxxxxx are mm-oom-deduplicate-victim-selection-code-for-memcg-and-global-oom.patch mm-memcontrol-add-sanity-checks-for-memcg-idref-on-get-put.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html