[PATCH 7/9] sched: introduce this_rq_lock_irq()

[Johannes Weiner <hannes@cmpxchg.org>]

do_sched_yield() disables IRQs, looks up this_rq() and locks it. The
next patch is adding another site with the same pattern, so provide a
convenience function for it.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
---
 kernel/sched/core.c  |  4 +---
 kernel/sched/sched.h | 12 ++++++++++++
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index fe365c9a08e9..61059e671fc6 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -4960,9 +4960,7 @@ static void do_sched_yield(void)
 	struct rq_flags rf;
 	struct rq *rq;
 
-	local_irq_disable();
-	rq = this_rq();
-	rq_lock(rq, &rf);
+	rq = this_rq_lock_irq(&rf);
 
 	schedstat_inc(rq->yld_count);
 	current->sched_class->yield_task(rq);
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index eb9b1326906c..83db5de1464c 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1126,6 +1126,18 @@ rq_unlock(struct rq *rq, struct rq_flags *rf)
 	raw_spin_unlock(&rq->lock);
 }
 
+static inline struct rq *
+this_rq_lock_irq(struct rq_flags *rf)
+	__acquires(rq->lock)
+{
+	struct rq *rq;
+
+	local_irq_disable();
+	rq = this_rq();
+	rq_lock(rq, rf);
+	return rq;
+}
+
 #ifdef CONFIG_NUMA
 enum numa_topology_type {
 	NUMA_DIRECT,
-- 
2.18.0