* [PATCH] memcg: replace in_interrupt() by !in_task() in active_memcg()
[not found] <CALvZod5-XtaeawPtEgnp9xwouy0KfuDbpykB6Z3b+8YJyCrLVA@mail.gmail.com>
@ 2021-07-26 16:53 ` Vasily Averin
2021-07-26 16:57 ` Shakeel Butt
0 siblings, 1 reply; 2+ messages in thread
From: Vasily Averin @ 2021-07-26 16:53 UTC (permalink / raw)
To: Shakeel Butt, Johannes Weiner, Michal Hocko, Vladimir Davydov,
Roman Gushchin, Andrew Morton
Cc: cgroups, linux-kernel, linux-mm
set_active_memcg() uses in_interrupt() check to select proper storage for
cgroup: pointer on task struct or per-cpu pointer.
It isn't fully correct: obsoleted in_interrupt() includes tasks with disabled BH.
It's better to use '!in_task()' instead.
Link: https://lkml.org/lkml/2021/7/26/487
Fixes: 37d5985c003d ("mm: kmem: prepare remote memcg charging infra for interrupt contexts")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
---
include/linux/sched/mm.h | 2 +-
mm/memcontrol.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h
index e24b1fe348e3..9dd071f78dba 100644
--- a/include/linux/sched/mm.h
+++ b/include/linux/sched/mm.h
@@ -306,7 +306,7 @@ set_active_memcg(struct mem_cgroup *memcg)
{
struct mem_cgroup *old;
- if (in_interrupt()) {
+ if (!in_task()) {
old = this_cpu_read(int_active_memcg);
this_cpu_write(int_active_memcg, memcg);
} else {
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index ae1f5d0cb581..3ebf792ef2c0 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -905,7 +905,7 @@ EXPORT_SYMBOL(mem_cgroup_from_task);
static __always_inline struct mem_cgroup *active_memcg(void)
{
- if (in_interrupt())
+ if (!in_task())
return this_cpu_read(int_active_memcg);
else
return current->active_memcg;
--
2.25.1
^ permalink raw reply [flat|nested] 2+ messages in thread