From: Peter Zijlstra <peterz@infradead.org> mainline inclusion from mainline-v6.7-rc1 commit 7a50f76674f8b6f4f30a1cec954179f10e20110c category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/8335IDC9YK Reference: https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commi... -------------------------------- Use guards to reduce gotos and simplify control flow. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Conflicts: kernel/sched/core.c [Conflicts with 002c90dd0cec ("sched: Fix race between yield_to() and try_to_wake_up()"), so refer to the mainline to solve this conflict in raw_spin_lock_irqsave mode.] Signed-off-by: Zicheng Qu <quzicheng@huawei.com> Signed-off-by: cheliequan <cheliequan@inspur.com> Signed-off-by: Luo Gengkun <luogengkun2@huawei.com> --- kernel/sched/core.c | 67 ++++++++++++++++++++------------------------- 1 file changed, 29 insertions(+), 38 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 32f4181fd342..29ab91bafc1c 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -9001,55 +9001,46 @@ int __sched yield_to(struct task_struct *p, bool preempt) { struct task_struct *curr = current; struct rq *rq, *p_rq; - unsigned long flags; int yielded = 0; - raw_spin_lock_irqsave(&p->pi_lock, flags); - rq = this_rq(); + scoped_guard (raw_spinlock_irqsave, &p->pi_lock) { + rq = this_rq(); again: - p_rq = task_rq(p); - /* - * If we're the only runnable task on the rq and target rq also - * has only one task, there's absolutely no point in yielding. - */ - if (rq->nr_running == 1 && p_rq->nr_running == 1) { - yielded = -ESRCH; - goto out_irq; - } + p_rq = task_rq(p); + /* + * If we're the only runnable task on the rq and target rq also + * has only one task, there's absolutely no point in yielding. + */ + if (rq->nr_running == 1 && p_rq->nr_running == 1) + return -ESRCH; - double_rq_lock(rq, p_rq); - if (task_rq(p) != p_rq) { - double_rq_unlock(rq, p_rq); - goto again; - } + guard(double_rq_lock)(rq, p_rq); + if (task_rq(p) != p_rq) + goto again; - if (!curr->sched_class->yield_to_task) - goto out_unlock; + if (!curr->sched_class->yield_to_task) + return 0; - if (curr->sched_class != p->sched_class) - goto out_unlock; + if (curr->sched_class != p->sched_class) + return 0; - if (task_on_cpu(p_rq, p) || !task_is_running(p)) - goto out_unlock; + if (task_on_cpu(p_rq, p) || !task_is_running(p)) + return 0; - yielded = curr->sched_class->yield_to_task(rq, p); - if (yielded) { - schedstat_inc(rq->yld_count); - /* - * Make p's CPU reschedule; pick_next_entity takes care of - * fairness. - */ - if (preempt && rq != p_rq) - resched_curr(p_rq); + yielded = curr->sched_class->yield_to_task(rq, p); + if (yielded) { + schedstat_inc(rq->yld_count); + /* + * Make p's CPU reschedule; pick_next_entity + * takes care of fairness. + */ + if (preempt && rq != p_rq) + resched_curr(p_rq); + } } -out_unlock: - double_rq_unlock(rq, p_rq); -out_irq: - raw_spin_unlock_irqrestore(&p->pi_lock, flags); - - if (yielded > 0) + if (yielded) schedule(); return yielded; -- 2.34.1