From: Shakeel Butt <shakeelb@xxxxxxxxxx> Subject: mm: memcontrol: fix percpu vmstats and vmevents flush Instead of using raw_cpu_read() use per_cpu() to read the actual data of the corresponding cpu otherwise we will be reading the data of the current cpu for the number of online CPUs. Link: http://lkml.kernel.org/r/20190829203110.129263-1-shakeelb@xxxxxxxxxx Fixes: bb65f89b7d3d ("mm: memcontrol: flush percpu vmevents before releasing memcg") Fixes: c350a99ea2b1 ("mm: memcontrol: flush percpu vmstats before releasing memcg") Signed-off-by: Shakeel Butt <shakeelb@xxxxxxxxxx> Acked-by: Roman Gushchin <guro@xxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Vladimir Davydov <vdavydov.dev@xxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memcontrol.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) --- a/mm/memcontrol.c~mm-memcontrol-fix-percpu-vmstats-and-vmevents-flush +++ a/mm/memcontrol.c @@ -3278,7 +3278,7 @@ static void memcg_flush_percpu_vmstats(s for_each_online_cpu(cpu) for (i = min_idx; i < max_idx; i++) - stat[i] += raw_cpu_read(memcg->vmstats_percpu->stat[i]); + stat[i] += per_cpu(memcg->vmstats_percpu->stat[i], cpu); for (mi = memcg; mi; mi = parent_mem_cgroup(mi)) for (i = min_idx; i < max_idx; i++) @@ -3296,8 +3296,8 @@ static void memcg_flush_percpu_vmstats(s for_each_online_cpu(cpu) for (i = min_idx; i < max_idx; i++) - stat[i] += raw_cpu_read( - pn->lruvec_stat_cpu->count[i]); + stat[i] += per_cpu( + pn->lruvec_stat_cpu->count[i], cpu); for (pi = pn; pi; pi = parent_nodeinfo(pi, node)) for (i = min_idx; i < max_idx; i++) @@ -3316,8 +3316,8 @@ static void memcg_flush_percpu_vmevents( for_each_online_cpu(cpu) for (i = 0; i < NR_VM_EVENT_ITEMS; i++) - events[i] += raw_cpu_read( - memcg->vmstats_percpu->events[i]); + events[i] += per_cpu(memcg->vmstats_percpu->events[i], + cpu); for (mi = memcg; mi; mi = parent_mem_cgroup(mi)) for (i = 0; i < NR_VM_EVENT_ITEMS; i++) _
