From patchwork Fri Mar 29 15:09:30 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?SsO8cmdlbiBHcm/Dnw==?= X-Patchwork-Id: 10877313 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 81DC31575 for ; Fri, 29 Mar 2019 15:12:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6AB9629862 for ; Fri, 29 Mar 2019 15:12:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 68D012986C; Fri, 29 Mar 2019 15:12:06 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id DDDE4298A4 for ; Fri, 29 Mar 2019 15:12:05 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1h9t9R-0005RQ-MJ; Fri, 29 Mar 2019 15:10:37 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1h9t8p-0003v8-0x for xen-devel@lists.xenproject.org; Fri, 29 Mar 2019 15:09:59 +0000 X-Inumbo-ID: b45b3058-5234-11e9-8ce2-733247f92772 Received: from mx1.suse.de (unknown [195.135.220.15]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id b45b3058-5234-11e9-8ce2-733247f92772; Fri, 29 Mar 2019 15:09:53 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id AB225B005; Fri, 29 Mar 2019 15:09:52 +0000 (UTC) From: Juergen Gross To: xen-devel@lists.xenproject.org Date: Fri, 29 Mar 2019 16:09:30 +0100 Message-Id: <20190329150934.17694-46-jgross@suse.com> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20190329150934.17694-1-jgross@suse.com> References: <20190329150934.17694-1-jgross@suse.com> Subject: [Xen-devel] [PATCH RFC 45/49] xen/sched: support allocating multiple vcpus into one sched item X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Juergen Gross , George Dunlap , Dario Faggioli MIME-Version: 1.0 Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" X-Virus-Scanned: ClamAV using ClamSMTP With a scheduling granularity greater than 1 multiple vcpus share the same struct sched_item. Support that. Setting the initial processor must be done carefully: we can't use sched_set_res() as that relies on for_each_sched_item_vcpu() which in turn needs the vcpu already as a member of the domain's vcpu linked list, which isn't the case. Signed-off-by: Juergen Gross --- xen/common/schedule.c | 75 ++++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 62 insertions(+), 13 deletions(-) diff --git a/xen/common/schedule.c b/xen/common/schedule.c index 7fb0b1ed4e..a2140b3d7c 100644 --- a/xen/common/schedule.c +++ b/xen/common/schedule.c @@ -300,10 +300,25 @@ static void sched_spin_unlock_double(spinlock_t *lock1, spinlock_t *lock2, spin_unlock_irqrestore(lock1, flags); } -static void sched_free_item(struct sched_item *item) +static void sched_free_item(struct sched_item *item, struct vcpu *v) { struct sched_item *prev_item; struct domain *d = item->domain; + struct vcpu *vitem; + unsigned int cnt = 0; + + /* Don't count to be released vcpu, might be not in vcpu list yet. */ + for_each_sched_item_vcpu ( item, vitem ) + if ( vitem != v ) + cnt++; + + v->sched_item = NULL; + + if ( cnt ) + return; + + if ( item->vcpu == v ) + item->vcpu = v->next_in_list; if ( d->sched_item_list == item ) d->sched_item_list = item->next_in_list; @@ -319,8 +334,6 @@ static void sched_free_item(struct sched_item *item) } } - item->vcpu->sched_item = NULL; - free_cpumask_var(item->cpu_hard_affinity); free_cpumask_var(item->cpu_hard_affinity_tmp); free_cpumask_var(item->cpu_hard_affinity_saved); @@ -329,17 +342,36 @@ static void sched_free_item(struct sched_item *item) xfree(item); } +static void sched_item_add_vcpu(struct sched_item *item, struct vcpu *v) +{ + v->sched_item = item; + if ( !item->vcpu || item->vcpu->vcpu_id > v->vcpu_id ) + { + item->vcpu = v; + item->item_id = v->vcpu_id; + } +} + static struct sched_item *sched_alloc_item(struct vcpu *v) { struct sched_item *item, **prev_item; struct domain *d = v->domain; + for_each_sched_item ( d, item ) + if ( item->vcpu->vcpu_id / sched_granularity == + v->vcpu_id / sched_granularity ) + break; + + if ( item ) + { + sched_item_add_vcpu(item, v); + return item; + } + if ( (item = xzalloc(struct sched_item)) == NULL ) return NULL; - v->sched_item = item; - item->vcpu = v; - item->item_id = v->vcpu_id; + sched_item_add_vcpu(item, v); item->domain = d; for ( prev_item = &d->sched_item_list; *prev_item; @@ -360,7 +392,7 @@ static struct sched_item *sched_alloc_item(struct vcpu *v) return item; fail: - sched_free_item(item); + sched_free_item(item, v); return NULL; } @@ -404,8 +436,6 @@ int sched_init_vcpu(struct vcpu *v) item->idle_cnt++; } - sched_set_res(item, per_cpu(sched_res, processor)); - /* Initialise the per-vcpu timers. */ init_timer(&v->periodic_timer, vcpu_periodic_timer_fn, v, v->processor); @@ -414,10 +444,22 @@ int sched_init_vcpu(struct vcpu *v) init_timer(&v->poll_timer, poll_timer_fn, v, v->processor); + /* If this is not the first vcpu of the item we are done. */ + if ( item->priv != NULL ) + { + /* We can rely on previous vcpu to exist. */ + v->processor = cpumask_next(d->vcpu[v->vcpu_id - 1]->processor, + item->res->cpus); + return 0; + } + + /* The first vcpu of an item can be set via sched_set_res(). */ + sched_set_res(item, per_cpu(sched_res, processor)); + item->priv = SCHED_OP(dom_scheduler(d), alloc_vdata, item, d->sched_priv); if ( item->priv == NULL ) { - sched_free_item(item); + sched_free_item(item, v); return 1; } @@ -571,9 +613,16 @@ void sched_destroy_vcpu(struct vcpu *v) kill_timer(&v->poll_timer); if ( test_and_clear_bool(v->is_urgent) ) atomic_dec(&per_cpu(sched_res, v->processor)->urgent_count); - SCHED_OP(vcpu_scheduler(v), remove_item, item); - SCHED_OP(vcpu_scheduler(v), free_vdata, item->priv); - sched_free_item(item); + /* + * Vcpus are being destroyed top-down. So being the first vcpu of an item + * is the same as being the only one. + */ + if ( item->vcpu == v ) + { + SCHED_OP(vcpu_scheduler(v), remove_item, item); + SCHED_OP(vcpu_scheduler(v), free_vdata, item->priv); + sched_free_item(item, v); + } } int sched_init_domain(struct domain *d, int poolid)