[RFC PATCH v3 bpf-next 2/5] sched: use static_branch_likely() for the NUMA balancing tick check

[Yafang Shao <laoar.shao@gmail.com>]

task_tick_fair() checks sched_numa_balancing on every tick. The
static_branch_unlikely() annotation reserves the nop for the disabled case,
so the default configuration (NUMA_BALANCING_DEFAULT_ENABLED=y) pays a
taken jump per tick. Flip the polarity to static_branch_likely() so that
the fast path matches the default.

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
---
 kernel/sched/fair.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 973647ad6c2d..71dc47d6114d 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -15351,7 +15351,7 @@ static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued)
 	if (queued)
 		return;
 
-	if (static_branch_unlikely(&sched_numa_balancing))
+	if (static_branch_likely(&sched_numa_balancing))
 		task_tick_numa(rq, curr);
 
 	task_tick_cache(rq, curr);
-- 
2.52.0