On Fri, Aug 30, 2019 at 10:49:42AM -0700, subhra mazumdar wrote: > Search SMT siblings before all CPUs in LLC domain for idle CPU. This helps > in L1 cache locality. > --- > kernel/sched/fair.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index 8856503..94dd4a32 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -6274,11 +6274,11 @@ static int select_idle_sibling(struct task_struct *p, > int prev, int target) > return i; > } > > - i = select_idle_cpu(p, sd, target); > + i = select_idle_smt(p, target); > if ((unsigned)i < nr_cpumask_bits) > return i; > > - i = select_idle_smt(p, target); > + i = select_idle_cpu(p, sd, target); > if ((unsigned)i < nr_cpumask_bits) > return i; >
But it is absolutely conceptually wrong. An idle core is a much better target than an idle sibling.
