From 19b7bdc3a1550ab2550427c33395bec7caeaf72d Mon Sep 17 00:00:00 2001 From: Zhan Xusheng Date: Mon, 29 Jun 2026 11:02:00 +0800 Subject: [PATCH] sched/fair: Fix stale comments referring to removed CFS concepts A few comments still describe the pre-EEVDF CFS world: - sysctl_sched_base_slice is documented as "Minimal preemption granularity for CPU-bound tasks". That was the wording of the old sysctl_sched_min_granularity, renamed in commit e4ec3318a17f ("sched/debug: Rename sysctl_sched_min_granularity to sysctl_sched_base_slice"). Under EEVDF it is the default base time slice / request size (r_i) used to compute the virtual deadline, as documented in update_deadline(). - Two comments still mention sched_slice(), which was removed when the fair class committed to EEVDF in commit 5e963f2bd465 ("sched/fair: Commit to EEVDF"). The dequeue-path comment should simply refer to the task's slice (se->slice); the forced-idle comment describes the slice accounting now performed by __entity_slice_used(), which is the function actually used right below it. No functional changes. [ mingo: Ported to a more recent scheduler base ] Signed-off-by: Zhan Xusheng Signed-off-by: Ingo Molnar Cc: Peter Zijlstra Link: https://patch.msgid.link/20260629030200.3165589-1-zhanxusheng@xiaomi.com --- kernel/sched/fair.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index ce05acf52d35..fc6cd55f9d22 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -73,7 +73,10 @@ unsigned int sysctl_sched_tunable_scaling = SCHED_TUNABLESCALING_LOG; /* - * Minimal preemption granularity for CPU-bound tasks: + * Default base time slice (request size r_i) for SCHED_NORMAL/SCHED_BATCH: + * + * Under EEVDF this is the request size used to compute the virtual + * deadline; see update_deadline(). * * (default: 0.70 msec * (1 + ilog(ncpus)), units: nanoseconds) */ @@ -14676,7 +14679,7 @@ static inline void task_tick_core(struct rq *rq, struct task_struct *curr) * if the sibling is forced idle, then trigger schedule to * give forced idle task a chance. * - * sched_slice() considers only this active rq and it gets the + * __entity_slice_used() considers only this active rq and it gets the * whole slice. But during force idle, we have siblings acting * like a single runqueue and hence we need to consider runnable * tasks on this CPU and the forced idle CPU. Ideally, we should