On 28/08/2020 12:27, Qais Yousef wrote: > On 08/28/20 10:00, [email protected] wrote: >> From: Vincent Donnefort <[email protected]> >> >> rq->cpu_capacity is a key element in several scheduler parts, such as EAS >> task placement and load balancing. Tracking this value enables testing >> and/or debugging by a toolkit. >> >> Signed-off-by: Vincent Donnefort <[email protected]> >> >> diff --git a/include/linux/sched.h b/include/linux/sched.h > > [...] > >> +int sched_trace_rq_cpu_capacity(struct rq *rq) >> +{ >> + return rq ? >> +#ifdef CONFIG_SMP >> + rq->cpu_capacity >> +#else >> + SCHED_CAPACITY_SCALE >> +#endif >> + : -1; >> +} >> +EXPORT_SYMBOL_GPL(sched_trace_rq_cpu_capacity); >> + > > The placement of this #ifdef looks odd to me. But FWIW > > Reviewed-by: Qais Yousef <[email protected]>
Returning -1 for cpu_capacity? It makes sense for sched_trace_rq_cpu() but for cpu_capacity? Can you remind me why we have all these helper functions like sched_trace_rq_cpu_capacity? In case we would let the extra code (which transforms trace points into trace events) know the internals of struct rq we could handle those things in the TRACE_EVENT and/or the register_trace_##name(void (*probe)(data_proto), void *data) thing. We always said when the internal things will change this extra code will break. So that's not an issue.
