[PATCH v3 03/10] sched/psi: save percpu memory when !psi_cgroups_enabled
From: Chengming Zhou <hidden>
Date: 2022-08-24 08:20:07
Also in:
cgroups, lkml
Subsystem:
pressure stall information (psi), scheduler, the rest · Maintainers:
Johannes Weiner, Suren Baghdasaryan, Ingo Molnar, Peter Zijlstra, Juri Lelli, Vincent Guittot, Linus Torvalds
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 <redacted> 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