lkml.org 
[lkml]   [2022]   [Aug]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v3 03/10] sched/psi: save percpu memory when !psi_cgroups_enabled
Date
We won't use cgroup psi_group when !psi_cgroups_enabled, so don't
bother to alloc percpu memory and init for it.

Also don't need to migrate task PSI stats between cgroups in
cgroup_move_task().

Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
---
kernel/sched/psi.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c
index 39463dcc16bb..77d53c03a76f 100644
--- a/kernel/sched/psi.c
+++ b/kernel/sched/psi.c
@@ -201,6 +201,7 @@ void __init psi_init(void)
{
if (!psi_enable) {
static_branch_enable(&psi_disabled);
+ static_branch_disable(&psi_cgroups_enabled);
return;
}

@@ -950,7 +951,7 @@ void psi_memstall_leave(unsigned long *flags)
#ifdef CONFIG_CGROUPS
int psi_cgroup_alloc(struct cgroup *cgroup)
{
- if (static_branch_likely(&psi_disabled))
+ if (!static_branch_likely(&psi_cgroups_enabled))
return 0;

cgroup->psi = kzalloc(sizeof(struct psi_group), GFP_KERNEL);
@@ -968,7 +969,7 @@ int psi_cgroup_alloc(struct cgroup *cgroup)

void psi_cgroup_free(struct cgroup *cgroup)
{
- if (static_branch_likely(&psi_disabled))
+ if (!static_branch_likely(&psi_cgroups_enabled))
return;

cancel_delayed_work_sync(&cgroup->psi->avgs_work);
@@ -996,7 +997,7 @@ void cgroup_move_task(struct task_struct *task, struct css_set *to)
struct rq_flags rf;
struct rq *rq;

- if (static_branch_likely(&psi_disabled)) {
+ if (!static_branch_likely(&psi_cgroups_enabled)) {
/*
* Lame to do this here, but the scheduler cannot be locked
* from the outside, so we move cgroups from inside sched/.
--
2.37.2
\
 
 \ /
  Last update: 2022-08-24 10:20    [W:1.640 / U:0.020 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site