The write side of this is xchg()/smp_mb(), so that's all good. Just a
few sites missing a READ_ONCE.
Signed-off-by: Chris Down <chris@xxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Roman Gushchin <guro@xxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: linux-mm@xxxxxxxxx
Cc: cgroups@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: kernel-team@xxxxxx
---
mm/memcontrol.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index e0ed790a2a8c..57048a38c75d 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1511,7 +1511,7 @@ void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg)
if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
pr_info("swap: usage %llukB, limit %llukB, failcnt %lu\n",
K((u64)page_counter_read(&memcg->swap)),
- K((u64)memcg->swap.max), memcg->swap.failcnt);
+ K((u64)READ_ONCE(memcg->swap.max)), memcg->swap.failcnt);
else {
pr_info("memory+swap: usage %llukB, limit %llukB, failcnt %lu\n",
K((u64)page_counter_read(&memcg->memsw)),
@@ -1544,7 +1544,7 @@ unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg)
unsigned long swap_max;
memsw_max = memcg->memsw.max;
- swap_max = memcg->swap.max;
+ swap_max = READ_ONCE(memcg->swap.max);
swap_max = min(swap_max, (unsigned long)total_swap_pages);
max = min(max + swap_max, memsw_max);
}
@@ -7025,7 +7025,8 @@ bool mem_cgroup_swap_full(struct page *page)
return false;
for (; memcg != root_mem_cgroup; memcg = parent_mem_cgroup(memcg))
- if (page_counter_read(&memcg->swap) * 2 >= memcg->swap.max)
+ if (page_counter_read(&memcg->swap) * 2 >=
+ READ_ONCE(memcg->swap.max))
return true;
return false;
--
2.25.1
