On 28/02/2020 10:07, Parth Shah wrote: > Introduce the latency_nice attribute to sched_attr and provide a > mechanism to change the value with the use of sched_setattr/sched_getattr > syscall. > > Also add new flag "SCHED_FLAG_LATENCY_NICE" to hint the change in > latency_nice of the task on every sched_setattr syscall. > > Signed-off-by: Parth Shah <[email protected]> > Reviewed-by: Qais Yousef <[email protected]>
[...] ndif /* _UAPI_LINUX_SCHED_TYPES_H */ > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index 866ea3d2d284..cd1fb9c8be26 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -4710,6 +4710,9 @@ static void __setscheduler_params(struct task_struct *p, > p->rt_priority = attr->sched_priority; > p->normal_prio = normal_prio(p); > set_load_weight(p, true); > + > + if (attr->sched_flags & SCHED_FLAG_LATENCY_NICE) > + p->latency_nice = attr->sched_latency_nice; > } How do you make sure that p->latency_nice can be set independently from p->static_prio? AFAICS, util_clamp achieves this by relying on SCHED_FLAG_KEEP_PARAMS, so completely bypassing __setscheduler_params() and using it's own __setscheduler_uclamp(). [...]
