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The cpu_acquire/release notice is > > printed on every scheduler enable. > > > > Switch both to pr_warn_once() so each deprecation is reported a single > > time, and add the missing newline to the slice/dsq_vtime message. > > I guess this should be warned for once per BPF scheduler like > sch->warned_deprecated_rq Yeah, I agree. The thing is that we can load multiple different BPF schedulers, and we'd want to get these messages for each of them. So ideally we need something like sch->warned_deprecated_rq. Thanks, -Andrea > > > > > Signed-off-by: Breno Leitao > > --- > > kernel/sched/ext/ext.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/kernel/sched/ext/ext.c b/kernel/sched/ext/ext.c > > index 691d53fe0f648..708eb9024cb25 100644 > > --- a/kernel/sched/ext/ext.c > > +++ b/kernel/sched/ext/ext.c > > @@ -6988,7 +6988,7 @@ static int validate_ops(struct scx_sched *sch, const struct sched_ext_ops *ops) > > * run past the BPF allocation. Skip for cid-form. > > */ > > if (!sch->is_cid_type && (ops->cpu_acquire || ops->cpu_release)) > > - pr_warn("ops->cpu_acquire/release() are deprecated, use sched_switch TP instead\n"); > > + pr_warn_once("ops->cpu_acquire/release() are deprecated, use sched_switch TP instead\n"); > > > > /* > > * Sub-scheduler support is tied to the cid-form struct_ops. A sub-sched > > @@ -7806,7 +7806,7 @@ static int bpf_scx_btf_struct_access(struct bpf_verifier_log *log, > > off + size <= offsetofend(struct task_struct, scx.slice)) || > > (off >= offsetof(struct task_struct, scx.dsq_vtime) && > > off + size <= offsetofend(struct task_struct, scx.dsq_vtime))) { > > - pr_warn("sched_ext: Writing directly to p->scx.slice/dsq_vtime is deprecated, use scx_bpf_task_set_slice/dsq_vtime()"); > > + pr_warn_once("sched_ext: Writing directly to p->scx.slice/dsq_vtime is deprecated, use scx_bpf_task_set_slice/dsq_vtime()\n"); > > return SCALAR_VALUE; > > } > > > > > > --- > > base-commit: 4e5dfb7c84012007c3c7061126491bbc92d71bf1 > > change-id: 20260623-scx_warning-0df49c442afb > > > > Best regards, >