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charset=us-ascii Content-Disposition: inline In-Reply-To: <20251017093214.70029-3-arighi@nvidia.com> Hi! On 17/10/25 11:25, Andrea Righi wrote: > From: Joel Fernandes > > Currently the DL server interface for applying parameters checks > CFS-internals to identify if the server is active. This is error-prone > and makes it difficult when adding new servers in the future. > > Fix it, by using dl_server_active() which is also used by the DL server > code to determine if the DL server was started. > > Acked-by: Tejun Heo > Reviewed-by: Andrea Righi > Signed-off-by: Joel Fernandes > --- > kernel/sched/debug.c | 11 ++++++++--- > 1 file changed, 8 insertions(+), 3 deletions(-) > > diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c > index 6cf9be6eea49a..e71f6618c1a6a 100644 > --- a/kernel/sched/debug.c > +++ b/kernel/sched/debug.c > @@ -354,6 +354,8 @@ static ssize_t sched_fair_server_write(struct file *filp, const char __user *ubu > return err; > > scoped_guard (rq_lock_irqsave, rq) { > + bool is_active; > + > runtime = rq->fair_server.dl_runtime; > period = rq->fair_server.dl_period; > > @@ -376,8 +378,11 @@ static ssize_t sched_fair_server_write(struct file *filp, const char __user *ubu > return -EINVAL; > } > > - update_rq_clock(rq); > - dl_server_stop(&rq->fair_server); > + is_active = dl_server_active(&rq->fair_server); > + if (is_active) { > + update_rq_clock(rq); > + dl_server_stop(&rq->fair_server); > + } Won't this reintroduce what bb4700adc3abe ("sched/deadline: Always stop dl-server before changing parameters") fixed? Thanks, Juri