From nobody Thu Dec 18 08:11:47 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0AA41C05052 for ; Mon, 14 Aug 2023 15:08:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232805AbjHNPIn (ORCPT ); Mon, 14 Aug 2023 11:08:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52628 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232673AbjHNPIL (ORCPT ); Mon, 14 Aug 2023 11:08:11 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 129A010DB; Mon, 14 Aug 2023 08:08:08 -0700 (PDT) Date: Mon, 14 Aug 2023 15:08:06 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1692025686; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=YMGiIB3ZRF9xDuzowmKuMGbuFtNeEa/dk8I9+QRM62A=; b=crm6U1Y1puA8N68rUT3sEX9cqlewdFVZZCBRq2kQaq148y6iT29NohOJBl3R4JHIw97woh 7xHjXBayhMJk0NQ6r2W9ofkoLF7OEcAiReaWFOniBQ5nqt2iimWiIbAH0DttzvEUiw7Mbg e97CsAddUSTLIjegT3Gdvo5aoefxj0bEZOU/zvX3Ay3ML/Ifaxn0JAfz6udZTyWn3Aw3Me zG2Usu7G3Aul7UwVzJjMaZtJFROmUuySvRsOxWtjiy4Flml/EzC7OMEF28GsCM6N5hecsf TM+1B8Y3FcBMkRMEElHo9uvvhVwNsDabcRAxgS3sXMSCbVQZV7uy+et2T7FZSQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1692025686; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=YMGiIB3ZRF9xDuzowmKuMGbuFtNeEa/dk8I9+QRM62A=; b=A/v8uHIc6YkhrKwX4WgWj9AyS0n/YfPYLmkYO4r+DX+PvdR7DsEfNOJZKJtSJ7fiNpVY+S IuudXucGLZYvuDCQ== From: "tip-bot2 for Peter Zijlstra" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: sched/core] sched: Simplify: migrate_swap_stop() Cc: "Peter Zijlstra (Intel)" , Valentin Schneider , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20230801211811.964370836@infradead.org> References: <20230801211811.964370836@infradead.org> MIME-Version: 1.0 Message-ID: <169202568621.27769.9047614343930343004.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the sched/core branch of tip: Commit-ID: 5bb76f1ddf2a7dd98f5a89d7755600ed1b4a7fcd Gitweb: https://git.kernel.org/tip/5bb76f1ddf2a7dd98f5a89d7755600ed1= b4a7fcd Author: Peter Zijlstra AuthorDate: Tue, 01 Aug 2023 22:41:24 +02:00 Committer: Peter Zijlstra CommitterDate: Mon, 14 Aug 2023 17:01:25 +02:00 sched: Simplify: migrate_swap_stop() Use guards to reduce gotos and simplify control flow. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Valentin Schneider Link: https://lore.kernel.org/r/20230801211811.964370836@infradead.org --- kernel/sched/core.c | 23 +++++++---------------- kernel/sched/sched.h | 20 ++++++++++++++++++++ 2 files changed, 27 insertions(+), 16 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 6e8a8e9..66478a6 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3433,7 +3433,6 @@ static int migrate_swap_stop(void *data) { struct migration_swap_arg *arg =3D data; struct rq *src_rq, *dst_rq; - int ret =3D -EAGAIN; =20 if (!cpu_active(arg->src_cpu) || !cpu_active(arg->dst_cpu)) return -EAGAIN; @@ -3441,33 +3440,25 @@ static int migrate_swap_stop(void *data) src_rq =3D cpu_rq(arg->src_cpu); dst_rq =3D cpu_rq(arg->dst_cpu); =20 - double_raw_lock(&arg->src_task->pi_lock, - &arg->dst_task->pi_lock); - double_rq_lock(src_rq, dst_rq); + guard(double_raw_spinlock)(&arg->src_task->pi_lock, &arg->dst_task->pi_lo= ck); + guard(double_rq_lock)(src_rq, dst_rq); =20 if (task_cpu(arg->dst_task) !=3D arg->dst_cpu) - goto unlock; + return -EAGAIN; =20 if (task_cpu(arg->src_task) !=3D arg->src_cpu) - goto unlock; + return -EAGAIN; =20 if (!cpumask_test_cpu(arg->dst_cpu, arg->src_task->cpus_ptr)) - goto unlock; + return -EAGAIN; =20 if (!cpumask_test_cpu(arg->src_cpu, arg->dst_task->cpus_ptr)) - goto unlock; + return -EAGAIN; =20 __migrate_swap_task(arg->src_task, arg->dst_cpu); __migrate_swap_task(arg->dst_task, arg->src_cpu); =20 - ret =3D 0; - -unlock: - double_rq_unlock(src_rq, dst_rq); - raw_spin_unlock(&arg->dst_task->pi_lock); - raw_spin_unlock(&arg->src_task->pi_lock); - - return ret; + return 0; } =20 /* diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 9c5035c..c299a58 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -2614,6 +2614,12 @@ static inline void double_rq_clock_clear_update(stru= ct rq *rq1, struct rq *rq2) static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq = *rq2) {} #endif =20 +#define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...) \ +__DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__) \ +static inline class_##name##_t class_##name##_constructor(type *lock, type= *lock2) \ +{ class_##name##_t _t =3D { .lock =3D lock, .lock2 =3D lock2 }, *_T =3D &_= t; \ + _lock; return _t; } + #ifdef CONFIG_SMP =20 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2) @@ -2743,6 +2749,16 @@ static inline void double_raw_lock(raw_spinlock_t *l= 1, raw_spinlock_t *l2) raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING); } =20 +static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l= 2) +{ + raw_spin_unlock(l1); + raw_spin_unlock(l2); +} + +DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t, + double_raw_lock(_T->lock, _T->lock2), + double_raw_unlock(_T->lock, _T->lock2)) + /* * double_rq_unlock - safely unlock two runqueues * @@ -2800,6 +2816,10 @@ static inline void double_rq_unlock(struct rq *rq1, = struct rq *rq2) =20 #endif =20 +DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq, + double_rq_lock(_T->lock, _T->lock2), + double_rq_unlock(_T->lock, _T->lock2)) + extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq); extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);