From 2c8d046d5d51691550da023976815e7a64151636 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 18 Jun 2024 10:09:17 -1000 Subject: [PATCH] sched: Add normal_policy() A new BPF extensible sched_class will need to dynamically change how a task picks its sched_class. For example, if the loaded BPF scheduler progs fail, the tasks will be forced back on CFS even if the task's policy is set to the new sched_class. To support such mapping, add normal_policy() which wraps testing for %SCHED_NORMAL. This doesn't cause any behavior changes. v2: Update the description with more details on the expected use. Signed-off-by: Tejun Heo Reviewed-by: David Vernet Acked-by: Josh Don Acked-by: Hao Luo Acked-by: Barret Rhoden --- kernel/sched/fair.c | 2 +- kernel/sched/sched.h | 7 ++++++- 2 files changed, 7 insertions(+), 2 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 715d7c1f55df..d59537416865 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -8391,7 +8391,7 @@ static void check_preempt_wakeup_fair(struct rq *rq, struct task_struct *p, int * Batch and idle tasks do not preempt non-idle tasks (their preemption * is driven by the tick): */ - if (unlikely(p->policy != SCHED_NORMAL) || !sched_feat(WAKEUP_PREEMPTION)) + if (unlikely(!normal_policy(p->policy)) || !sched_feat(WAKEUP_PREEMPTION)) return; find_matching_se(&se, &pse); diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index a5a4f59151db..25660dc9f639 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -192,9 +192,14 @@ static inline int idle_policy(int policy) return policy == SCHED_IDLE; } +static inline int normal_policy(int policy) +{ + return policy == SCHED_NORMAL; +} + static inline int fair_policy(int policy) { - return policy == SCHED_NORMAL || policy == SCHED_BATCH; + return normal_policy(policy) || policy == SCHED_BATCH; } static inline int rt_policy(int policy)