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Signed-off-by: Peter Zijlstra (Intel) --- kernel/sched/fair.c | 16 ++++------------ 1 file changed, 4 insertions(+), 12 deletions(-) --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -15790,12 +15790,9 @@ int sched_group_set_idle(struct task_gro if (idle < 0 || idle > 1) return -EINVAL; - mutex_lock(&shares_mutex); - - if (tg->idle == idle) { - mutex_unlock(&shares_mutex); + guard(mutex)(&shares_mutex); + if (tg->idle == idle) return 0; - } tg->idle = idle; @@ -15805,13 +15802,12 @@ int sched_group_set_idle(struct task_gro struct cfs_rq *grp_cfs_rq = tg_cfs_rq(tg, i); bool was_idle = cfs_rq_is_idle(grp_cfs_rq); long idle_task_delta; - struct rq_flags rf; - rq_lock_irqsave(rq, &rf); + guard(rq_lock_irqsave)(rq); grp_cfs_rq->idle = idle; if (WARN_ON_ONCE(was_idle == cfs_rq_is_idle(grp_cfs_rq))) - goto next_cpu; + continue; idle_task_delta = grp_cfs_rq->h_nr_queued - grp_cfs_rq->h_nr_idle; @@ -15830,9 +15826,6 @@ int sched_group_set_idle(struct task_gro if (cfs_rq_is_idle(cfs_rq)) break; } - -next_cpu: - rq_unlock_irqrestore(rq, &rf); } /* Idle groups have minimum weight. */ @@ -15841,7 +15834,6 @@ int sched_group_set_idle(struct task_gro else __sched_group_set_shares(tg, NICE_0_LOAD); - mutex_unlock(&shares_mutex); return 0; }