[RFC][PATCH v2 07/10] sched/fair: Exclude the current CPU from find_new_ilb()

[Peter Zijlstra]

It is possible for find_new_ilb() to select the current CPU, however,
this only happens from newidle balancing, in which case need_resched()
will be true, and consequently nohz_csd_func() will not trigger the
softirq.

Exclude the current CPU from becoming an ILB target.

Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org>
---
 kernel/sched/fair.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -10026,6 +10026,10 @@ static inline int find_new_ilb(void)
 
        for_each_cpu_and(ilb, nohz.idle_cpus_mask,
                              housekeeping_cpumask(HK_FLAG_MISC)) {
+
+               if (ilb == smp_processor_id())
+                       continue;
+
                if (idle_cpu(ilb))
                        return ilb;
        }