On Thu, Jun 28, 2018 at 06:29:41PM +0200, Frederic Weisbecker wrote:
kernel/sched/core.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 78d8fac..da8f121 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3127,16 +3127,18 @@ static void sched_tick_remote(struct work_struct *work) u64 delta; rq_lock_irq(rq, &rf);
update_rq_clock(rq);delta = rq_clock_task(rq) - curr->se.exec_start;
if (!is_idle_task(curr)) {update_rq_clock(rq);delta = rq_clock_task(rq) - curr->se.exec_start;
/** Make sure the next tick runs within a reasonable* amount of time.*/WARN_ON_ONCE(delta > (u64)NSEC_PER_SEC * 3);curr->sched_class->task_tick(rq, curr, 0);
/** Make sure the next tick runs within a reasonable* amount of time.*/WARN_ON_ONCE(delta > (u64)NSEC_PER_SEC * 3);curr->sched_class->task_tick(rq, curr, 0);}
Instead of deep indent, how about we write it like so: ?
--- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3113,7 +3113,9 @@ static void sched_tick_remote(struct wor 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;
/* * Handle the tick only if it appears the remote CPU is running in full @@ -3122,26 +3124,28 @@ static void sched_tick_remote(struct wor * statistics and checks timeslices in a time-independent way, regardless * of when exactly it is running. */ - if (!idle_cpu(cpu) && tick_nohz_tick_stopped_cpu(cpu)) { - struct task_struct *curr; - u64 delta; - - rq_lock_irq(rq, &rf); - curr = rq->curr; - if (!is_idle_task(curr)) { - update_rq_clock(rq); - delta = rq_clock_task(rq) - curr->se.exec_start; - - /* - * Make sure the next tick runs within a reasonable - * amount of time. - */ - WARN_ON_ONCE(delta > (u64)NSEC_PER_SEC * 3); - curr->sched_class->task_tick(rq, curr, 0); - } - rq_unlock_irq(rq, &rf); - } + if (idle_cpu(cpu) || !tick_nohz_tick_stopped_cpu(cpu)) + goto out_requeue;
+ rq_lock_irq(rq, &rf); + curr = rq->curr; + if (is_idle_task(curr)) + goto out_unlock; + + update_rq_clock(rq); + delta = rq_clock_task(rq) - curr->se.exec_start; + + /* + * Make sure the next tick runs within a reasonable + * amount of time. + */ + WARN_ON_ONCE(delta > (u64)NSEC_PER_SEC * 3); + curr->sched_class->task_tick(rq, curr, 0); + +out_unlock: + rq_unlock_irq(rq, &rf); + +out_requeue: /* * Run the remote tick once per second (1Hz). This arbitrary * frequency is large enough to avoid overload but short enough