[RFC PATCH] sched, cgroup: cgroup1 can also take the non-RUNTIME_INF min

From: Liu Song
Date: Tue Sep 10 2024 - 03:49:09 EST


For the handling logic of child_quota, there is no need to distinguish
between cgroup1 and cgroup2, so unify the handling logic here.

Signed-off-by: Liu Song <liusong@xxxxxxxxxxxxxxxxx>
---
kernel/sched/core.c | 21 +++++----------------
1 file changed, 5 insertions(+), 16 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index e752146e59a4..8418c67faa69 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -9501,23 +9501,12 @@ static int tg_cfs_schedulable_down(struct task_group *tg, void *data)
parent_quota = parent_b->hierarchical_quota;

/*
- * Ensure max(child_quota) <= parent_quota. On cgroup2,
- * always take the non-RUNTIME_INF min. On cgroup1, only
- * inherit when no limit is set. In both cases this is used
- * by the scheduler to determine if a given CFS task has a
- * bandwidth constraint at some higher level.
+ * Ensure max(child_quota) <= parent_quota.
*/
- if (cgroup_subsys_on_dfl(cpu_cgrp_subsys)) {
- if (quota == RUNTIME_INF)
- quota = parent_quota;
- else if (parent_quota != RUNTIME_INF)
- quota = min(quota, parent_quota);
- } else {
- if (quota == RUNTIME_INF)
- quota = parent_quota;
- else if (parent_quota != RUNTIME_INF && quota > parent_quota)
- return -EINVAL;
- }
+ if (quota == RUNTIME_INF)
+ quota = parent_quota;
+ else if (parent_quota != RUNTIME_INF)
+ quota = min(quota, parent_quota);
}
cfs_b->hierarchical_quota = quota;

--
2.19.1.6.gb485710b