[tip: sched/core] sched/eevdf: Align update_protect_slice to set_protect_slice

[tip-bot2 for Vincent Guittot]

The following commit has been merged into the sched/core branch of tip:

Commit-ID:     4bf32ec3327d2d2286e96508cd128ce1592f43ce
Gitweb:        https://git.kernel.org/tip/4bf32ec3327d2d2286e96508cd128ce1592f43ce
Author:        Vincent Guittot <vincent.guittot@xxxxxxxxxx>
AuthorDate:    Mon, 21 Sep 2026 17:22:32 +02:00
Committer:     Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Fri, 25 Sep 2026 12:45:59 +02:00

sched/eevdf: Align update_protect_slice to set_protect_slice

Apply the same logic as for set_protect_slice when updating it.

Signed-off-by: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Link: https://patch.msgid.link/20260921152238.3804392-3-vincent.guittot@xxxxxxxxxx
---
 kernel/sched/fair.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 0969be2..82155d9 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -821,12 +821,6 @@ static u64 ineligible_vruntime(struct cfs_rq *cfs_rq)
 	if (curr && !curr->on_rq)
 		curr = NULL;
 
-	/*
-	 * This is called from set_next_task_fair(.first=true) /
-	 * set_protect_slice() so curr had better be set and on_rq.
-	 */
-	WARN_ON_ONCE(!curr);
-
 	if (weight) {
 		s64 runtime = cfs_rq->sum_w_vruntime;
 
@@ -1138,10 +1132,19 @@ static inline void set_protect_slice(struct cfs_rq *cfs_rq, struct sched_entity 
 
 static inline void update_protect_slice(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
-	u64 slice = cfs_rq_min_slice(cfs_rq);
 	u64 vruntime = min_vruntime(se->vruntime, avg_vruntime(cfs_rq));
+	u64 slice = normalized_sysctl_sched_base_slice;
+	u64 vprot;
+
+	if (sched_feat(RUN_TO_PARITY))
+		slice = cfs_rq_min_slice(cfs_rq);
+
+	vprot = min_vruntime(se->vprot, vruntime + calc_delta_fair(slice, se));
 
-	se->vprot = min_vruntime(se->vprot, vruntime + calc_delta_fair(slice, se));
+	if (sched_feat(PREEMPT_SHORT) && slice != se->slice)
+		vprot = min_vruntime(vprot, ineligible_vruntime(cfs_rq));
+
+	se->vprot = vprot;
 }
 
 static inline bool protect_slice(struct sched_entity *se)