[PATCH 2/2] sched/fair: Use rq in idle_cpu_without()

From: Pierre Gondois
Date: Wed Jan 03 2024 - 07:59:52 EST


idle_cpu_without() could receive a 'struct rq' instead of a
cpu number to avoid converting the cpu number to a 'struct rq'
two times. Indeed update_sg_wakeup_stats() already makes the
conversion.

Signed-off-by: Pierre Gondois <pierre.gondois@xxxxxxx>
---
kernel/sched/fair.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 93e928e76959..d38fec26fd3d 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -10184,15 +10184,13 @@ static unsigned int task_running_on_cpu(int cpu, struct task_struct *p)

/**
* idle_cpu_without - would a given CPU be idle without p ?
- * @cpu: the processor on which idleness is tested.
+ * @rq: the rq on which idleness is tested.
* @p: task which should be ignored.
*
* Return: 1 if the CPU would be idle. 0 otherwise.
*/
-static int idle_cpu_without(int cpu, struct task_struct *p)
+static int idle_cpu_without(struct rq *rq, struct task_struct *p)
{
- struct rq *rq = cpu_rq(cpu);
-
if (rq->curr != rq->idle && rq->curr != p)
return 0;

@@ -10247,7 +10245,7 @@ static inline void update_sg_wakeup_stats(struct sched_domain *sd,
/*
* No need to call idle_cpu_without() if nr_running is not 0
*/
- if (!nr_running && idle_cpu_without(i, p))
+ if (!nr_running && idle_cpu_without(rq, p))
sgs->idle_cpus++;

/* Check if task fits in the CPU */
--
2.25.1