The following commit has been merged into the sched/core branch of tip:
Commit-ID: 6dafc713e3b0d8ffbd696d200d8c9dd212ddcdfc
Gitweb: https://git.kernel.org/tip/6dafc713e3b0d8ffbd696d200d8c9dd212ddcdfc
Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate: Tue, 01 Aug 2023 22:41:28 +02:00
Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Mon, 14 Aug 2023 17:01:26 +02:00
sched: Simplify sched_tick_remote()
Use guards to reduce gotos and simplify control flow.
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Valentin Schneider <vschneid@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230801211812.236247952@xxxxxxxxxxxxx
---
kernel/sched/core.c | 39 ++++++++++++++++-----------------------
1 file changed, 16 insertions(+), 23 deletions(-)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index cd7f2ed..1b2fa91 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -5721,9 +5721,6 @@ static void sched_tick_remote(struct work_struct *work)
struct tick_work *twork = container_of(dwork, struct tick_work, work);
int cpu = twork->cpu;
struct rq *rq = cpu_rq(cpu);
- struct task_struct *curr;
- struct rq_flags rf;
- u64 delta;
int os;
/*
@@ -5733,30 +5730,26 @@ static void sched_tick_remote(struct work_struct *work)
* statistics and checks timeslices in a time-independent way, regardless
* of when exactly it is running.
*/
- if (!tick_nohz_tick_stopped_cpu(cpu))
- goto out_requeue;
+ if (tick_nohz_tick_stopped_cpu(cpu)) {
+ guard(rq_lock_irq)(rq);
+ struct task_struct *curr = rq->curr;
- rq_lock_irq(rq, &rf);
- curr = rq->curr;
- if (cpu_is_offline(cpu))
- goto out_unlock;
+ if (cpu_online(cpu)) {
+ update_rq_clock(rq);
- update_rq_clock(rq);
+ if (!is_idle_task(curr)) {
+ /*
+ * Make sure the next tick runs within a
+ * reasonable amount of time.
+ */
+ u64 delta = rq_clock_task(rq) - curr->se.exec_start;
+ WARN_ON_ONCE(delta > (u64)NSEC_PER_SEC * 3);
+ }
+ curr->sched_class->task_tick(rq, curr, 0);
- if (!is_idle_task(curr)) {
- /*
- * Make sure the next tick runs within a reasonable
- * amount of time.
- */
- delta = rq_clock_task(rq) - curr->se.exec_start;
- WARN_ON_ONCE(delta > (u64)NSEC_PER_SEC * 3);
+ calc_load_nohz_remote(rq);
+ }
}
- curr->sched_class->task_tick(rq, curr, 0);
-
- calc_load_nohz_remote(rq);
-out_unlock:
- rq_unlock_irq(rq, &rf);
-out_requeue:
/*
* Run the remote tick once per second (1Hz). This arbitrary
|