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 <tj@kernel.org>
Reviewed-by: David Vernet <dvernet@meta.com>
Acked-by: Josh Don <joshdon@google.com>
Acked-by: Hao Luo <haoluo@google.com>
Acked-by: Barret Rhoden <brho@google.com>
This commit is contained in:
Tejun Heo 2024-06-18 10:09:17 -10:00
parent 96fd6c65ef
commit 2c8d046d5d
2 changed files with 7 additions and 2 deletions

View File

@ -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);

View File

@ -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)