[RFC PATCH 16/16] sched/core: Set activation of non lock-holders to fast-path

[K Prateek Nayak <kprateek.nayak@amd.com>]

Tasks with a 0 count in "p->lock_nesting" cannot resolve to a
__mutex_owner(). Set actiavations and blocking of these task to
fast-path (plain __activate_task()) to avoid the overheads.

Signed-off-by: K Prateek Nayak <kprateek.nayak@amd.com>
---
 kernel/sched/core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 3153ad007447..3ab4cd36f887 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2508,7 +2508,7 @@ proxy_activate_blocked_task(struct rq *rq, struct task_struct *p, int en_flags)
 
 static void activate_blocked_task(struct rq *rq, struct task_struct *p, int en_flags)
 {
-	if (!sched_proxy_exec()) {
+	if (likely(!sched_proxy_exec() || !p->lock_nesting)) {
 		__activate_task(rq, p, en_flags);
 		return;
 	}
@@ -4065,7 +4065,7 @@ static inline void proxy_reset_donor(struct rq *rq)
 
 void __proxy_block_task(struct task_struct *p)
 {
-	if (!sched_proxy_exec())
+	if (!sched_proxy_exec() || likely(!p->lock_nesting))
 		return;
 
 	if (unlikely(p->is_linked && p->blocked_cpu != task_cpu(p))) {
-- 
2.34.1