From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-20.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 492B9C433B4 for ; Wed, 12 May 2021 10:29:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 133E5613FC for ; Wed, 12 May 2021 10:29:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231178AbhELKaM (ORCPT ); Wed, 12 May 2021 06:30:12 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:50472 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230355AbhELK3e (ORCPT ); Wed, 12 May 2021 06:29:34 -0400 Date: Wed, 12 May 2021 10:28:25 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1620815306; 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=PRspnrYzKPFksJCXjW7oP5g5iEr3XxbitW37+1gXz7w=; b=KLo4qAhpJruvgmD1O69JtNmZoFOHhXIN0fx3R1AAPRCCXUuHLY9J4g98SBaI3JTmYmcykM cB47Nyf9OrKKlZ8b8EWcZSbkb3JSy8tE5r1rJSc27vPkh67fZryUJeFnE9uVkbEiZOmOov Tham8VDDZNYImQLAVDt0qf3kv0F3aOHjUrN9f3VUrhUFG2DL5opFkoy/CnRzDHWevvRAgI iKqHKRpIQy1uNjH1JmrIigQTB3fDnNNHU6YWb4q+r4zga5RaxB0VzzkicoBQCqRpcEt6nd go9v+rVFVnd/3KUMQZ5Qq4jICwtFGh/iKRAuaha/Yq5xjPHHYG7tS9mGBMARWQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1620815306; 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=PRspnrYzKPFksJCXjW7oP5g5iEr3XxbitW37+1gXz7w=; b=BQFz891Av/daJ6J4xtOa3a978r/YdczKWTWXjs7NXKzUayKnQSpDdNOm36hg5xAyTUISrM yjX6zI+cXe/SYNCA== 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: Introduce sched_class::pick_task() Cc: "Peter Zijlstra (Intel)" , Vineeth Remanan Pillai , Don Hiatt , Hongyu Ning , Vincent Guittot , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20210422123308.437092775@infradead.org> References: <20210422123308.437092775@infradead.org> MIME-Version: 1.0 Message-ID: <162081530531.29796.2208363751943226264.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: 7bit 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: 21f56ffe4482e501b9e83737612493eeaac21f5a Gitweb: https://git.kernel.org/tip/21f56ffe4482e501b9e83737612493eeaac21f5a Author: Peter Zijlstra AuthorDate: Tue, 17 Nov 2020 18:19:32 -05:00 Committer: Peter Zijlstra CommitterDate: Wed, 12 May 2021 11:43:28 +02:00 sched: Introduce sched_class::pick_task() Because sched_class::pick_next_task() also implies sched_class::set_next_task() (and possibly put_prev_task() and newidle_balance) it is not state invariant. This makes it unsuitable for remote task selection. Signed-off-by: Peter Zijlstra (Intel) [Vineeth: folded fixes] Signed-off-by: Vineeth Remanan Pillai Signed-off-by: Peter Zijlstra (Intel) Tested-by: Don Hiatt Tested-by: Hongyu Ning Tested-by: Vincent Guittot Link: https://lkml.kernel.org/r/20210422123308.437092775@infradead.org --- kernel/sched/deadline.c | 16 ++++++++++++++-- kernel/sched/fair.c | 40 ++++++++++++++++++++++++++++++++++++--- kernel/sched/idle.c | 8 ++++++++- kernel/sched/rt.c | 15 +++++++++++++-- kernel/sched/sched.h | 3 +++- kernel/sched/stop_task.c | 14 ++++++++++++-- 6 files changed, 87 insertions(+), 9 deletions(-) diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index fb0eb9a..3829c5a 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1852,7 +1852,7 @@ static struct sched_dl_entity *pick_next_dl_entity(struct rq *rq, return rb_entry(left, struct sched_dl_entity, rb_node); } -static struct task_struct *pick_next_task_dl(struct rq *rq) +static struct task_struct *pick_task_dl(struct rq *rq) { struct sched_dl_entity *dl_se; struct dl_rq *dl_rq = &rq->dl; @@ -1864,7 +1864,18 @@ static struct task_struct *pick_next_task_dl(struct rq *rq) dl_se = pick_next_dl_entity(rq, dl_rq); BUG_ON(!dl_se); p = dl_task_of(dl_se); - set_next_task_dl(rq, p, true); + + return p; +} + +static struct task_struct *pick_next_task_dl(struct rq *rq) +{ + struct task_struct *p; + + p = pick_task_dl(rq); + if (p) + set_next_task_dl(rq, p, true); + return p; } @@ -2539,6 +2550,7 @@ DEFINE_SCHED_CLASS(dl) = { #ifdef CONFIG_SMP .balance = balance_dl, + .pick_task = pick_task_dl, .select_task_rq = select_task_rq_dl, .migrate_task_rq = migrate_task_rq_dl, .set_cpus_allowed = set_cpus_allowed_dl, diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 18960d0..51d72ab 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4419,6 +4419,8 @@ check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr) static void set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se) { + clear_buddies(cfs_rq, se); + /* 'current' is not kept within the tree. */ if (se->on_rq) { /* @@ -4478,7 +4480,7 @@ pick_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *curr) * Avoid running the skip buddy, if running something else can * be done without getting too unfair. */ - if (cfs_rq->skip == se) { + if (cfs_rq->skip && cfs_rq->skip == se) { struct sched_entity *second; if (se == curr) { @@ -4505,8 +4507,6 @@ pick_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *curr) se = cfs_rq->last; } - clear_buddies(cfs_rq, se); - return se; } @@ -7095,6 +7095,39 @@ preempt: set_last_buddy(se); } +#ifdef CONFIG_SMP +static struct task_struct *pick_task_fair(struct rq *rq) +{ + struct sched_entity *se; + struct cfs_rq *cfs_rq; + +again: + cfs_rq = &rq->cfs; + if (!cfs_rq->nr_running) + return NULL; + + do { + struct sched_entity *curr = cfs_rq->curr; + + /* When we pick for a remote RQ, we'll not have done put_prev_entity() */ + if (curr) { + if (curr->on_rq) + update_curr(cfs_rq); + else + curr = NULL; + + if (unlikely(check_cfs_rq_runtime(cfs_rq))) + goto again; + } + + se = pick_next_entity(cfs_rq, curr); + cfs_rq = group_cfs_rq(se); + } while (cfs_rq); + + return task_of(se); +} +#endif + struct task_struct * pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf) { @@ -11298,6 +11331,7 @@ DEFINE_SCHED_CLASS(fair) = { #ifdef CONFIG_SMP .balance = balance_fair, + .pick_task = pick_task_fair, .select_task_rq = select_task_rq_fair, .migrate_task_rq = migrate_task_rq_fair, diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c index 0194768..43646e7 100644 --- a/kernel/sched/idle.c +++ b/kernel/sched/idle.c @@ -439,6 +439,13 @@ static void set_next_task_idle(struct rq *rq, struct task_struct *next, bool fir schedstat_inc(rq->sched_goidle); } +#ifdef CONFIG_SMP +static struct task_struct *pick_task_idle(struct rq *rq) +{ + return rq->idle; +} +#endif + struct task_struct *pick_next_task_idle(struct rq *rq) { struct task_struct *next = rq->idle; @@ -506,6 +513,7 @@ DEFINE_SCHED_CLASS(idle) = { #ifdef CONFIG_SMP .balance = balance_idle, + .pick_task = pick_task_idle, .select_task_rq = select_task_rq_idle, .set_cpus_allowed = set_cpus_allowed_common, #endif diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index b3d39c3..a525447 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -1626,7 +1626,7 @@ static struct task_struct *_pick_next_task_rt(struct rq *rq) return rt_task_of(rt_se); } -static struct task_struct *pick_next_task_rt(struct rq *rq) +static struct task_struct *pick_task_rt(struct rq *rq) { struct task_struct *p; @@ -1634,7 +1634,17 @@ static struct task_struct *pick_next_task_rt(struct rq *rq) return NULL; p = _pick_next_task_rt(rq); - set_next_task_rt(rq, p, true); + + return p; +} + +static struct task_struct *pick_next_task_rt(struct rq *rq) +{ + struct task_struct *p = pick_task_rt(rq); + + if (p) + set_next_task_rt(rq, p, true); + return p; } @@ -2483,6 +2493,7 @@ DEFINE_SCHED_CLASS(rt) = { #ifdef CONFIG_SMP .balance = balance_rt, + .pick_task = pick_task_rt, .select_task_rq = select_task_rq_rt, .set_cpus_allowed = set_cpus_allowed_common, .rq_online = rq_online_rt, diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index ca30af3..fa990cd 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1953,6 +1953,9 @@ struct sched_class { #ifdef CONFIG_SMP int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf); int (*select_task_rq)(struct task_struct *p, int task_cpu, int flags); + + struct task_struct * (*pick_task)(struct rq *rq); + void (*migrate_task_rq)(struct task_struct *p, int new_cpu); void (*task_woken)(struct rq *this_rq, struct task_struct *task); diff --git a/kernel/sched/stop_task.c b/kernel/sched/stop_task.c index 55f3912..f988ebe 100644 --- a/kernel/sched/stop_task.c +++ b/kernel/sched/stop_task.c @@ -34,15 +34,24 @@ static void set_next_task_stop(struct rq *rq, struct task_struct *stop, bool fir stop->se.exec_start = rq_clock_task(rq); } -static struct task_struct *pick_next_task_stop(struct rq *rq) +static struct task_struct *pick_task_stop(struct rq *rq) { if (!sched_stop_runnable(rq)) return NULL; - set_next_task_stop(rq, rq->stop, true); return rq->stop; } +static struct task_struct *pick_next_task_stop(struct rq *rq) +{ + struct task_struct *p = pick_task_stop(rq); + + if (p) + set_next_task_stop(rq, p, true); + + return p; +} + static void enqueue_task_stop(struct rq *rq, struct task_struct *p, int flags) { @@ -123,6 +132,7 @@ DEFINE_SCHED_CLASS(stop) = { #ifdef CONFIG_SMP .balance = balance_stop, + .pick_task = pick_task_stop, .select_task_rq = select_task_rq_stop, .set_cpus_allowed = set_cpus_allowed_common, #endif