On Fri, Jun 12, 2020 at 9:21 AM Joel Fernandes <[email protected]> wrote: > > > +#ifdef CONFIG_SCHED_CORE > > + if (available_idle_cpu(cpu) && > > + sched_core_cookie_match(cpu_rq(cpu), p)) > > + break; > > +#else > > select_idle_cpu() is called only if no idle core could be found in the LLC by > select_idle_core(). > > So, would it be better here to just do the cookie equality check directly > instead of calling the sched_core_cookie_match() helper? More so, because > select_idle_sibling() is a fastpath. > Agree, this makes sense to me.
> AFAIR, that's what v4 did: > > if (available_idle_cpu(cpu)) > #ifdef CONFIG_SCHED_CORE > if (sched_core_enabled(cpu_rq(cpu)) && > (p->core_cookie == > cpu_rq(cpu)->core->core_cookie)) > break; > #else > break; > #endif > This patch was initially not in v4 and this is a merging of 4 patches suggested post-v4. During the initial round, code was like above. But since there looked like a code duplication in the different migration paths, it was consolidated into sched_core_cookie_match() and it caused this extra logic to this specific code path. As you mentioned, I also feel we do not need to check for core idleness in this path. Thanks, Vineeth
