From patchwork Tue May 28 10:32:20 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: 10964597 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 B3DA692A for ; Tue, 28 May 2019 10:34:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A55D62881A for ; Tue, 28 May 2019 10:34:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 99CE12857D; Tue, 28 May 2019 10:34:46 +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 7911728803 for ; Tue, 28 May 2019 10:34:45 +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 1hVZQ3-0004ZS-Tc; Tue, 28 May 2019 10:33:23 +0000 Received: from us1-rack-dfw2.inumbo.com ([104.130.134.6]) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hVZQ1-0004XR-Sc for xen-devel@lists.xenproject.org; Tue, 28 May 2019 10:33:21 +0000 X-Inumbo-ID: 030b03f4-8134-11e9-8980-bc764e045a96 Received: from mx1.suse.de (unknown [195.135.220.15]) by us1-rack-dfw2.inumbo.com (Halon) with ESMTPS id 030b03f4-8134-11e9-8980-bc764e045a96; Tue, 28 May 2019 10:33:20 +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 DCF46B00E; Tue, 28 May 2019 10:33:17 +0000 (UTC) From: Juergen Gross To: xen-devel@lists.xenproject.org Date: Tue, 28 May 2019 12:32:20 +0200 Message-Id: <20190528103313.1343-8-jgross@suse.com> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20190528103313.1343-1-jgross@suse.com> References: <20190528103313.1343-1-jgross@suse.com> Subject: [Xen-devel] [PATCH 07/60] xen/sched: build a linked list of struct sched_unit 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 , Tim Deegan , Stefano Stabellini , Wei Liu , Konrad Rzeszutek Wilk , George Dunlap , Andrew Cooper , Ian Jackson , Dario Faggioli , Julien Grall , Jan Beulich MIME-Version: 1.0 Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" X-Virus-Scanned: ClamAV using ClamSMTP In order to make it easy to iterate over sched_unit elements of a domain build a single linked list and add an iterator for it. The new list is guarded by the same mechanisms as the vcpu linked list as it is modified only via vcpu_create() or vcpu_destroy(). For completeness add another iterator for_each_sched_unit_vcpu() which will iterate over all vcpus if a sched_unit (right now only one). This will be needed later for larger scheduling granularity (e.g. cores). Signed-off-by: Juergen Gross --- xen/common/schedule.c | 56 ++++++++++++++++++++++++++++++++++++++++++------- xen/include/xen/sched.h | 9 ++++++++ 2 files changed, 58 insertions(+), 7 deletions(-) diff --git a/xen/common/schedule.c b/xen/common/schedule.c index 86a43f7192..49d25489ef 100644 --- a/xen/common/schedule.c +++ b/xen/common/schedule.c @@ -249,6 +249,52 @@ static void sched_spin_unlock_double(spinlock_t *lock1, spinlock_t *lock2, spin_unlock_irqrestore(lock1, flags); } +static void sched_free_unit(struct sched_unit *unit) +{ + struct sched_unit *prev_unit; + struct domain *d = unit->vcpu->domain; + + if ( d->sched_unit_list == unit ) + d->sched_unit_list = unit->next_in_list; + else + { + for_each_sched_unit ( d, prev_unit ) + { + if ( prev_unit->next_in_list == unit ) + { + prev_unit->next_in_list = unit->next_in_list; + break; + } + } + } + + unit->vcpu->sched_unit = NULL; + xfree(unit); +} + +static struct sched_unit *sched_alloc_unit(struct vcpu *v) +{ + struct sched_unit *unit, **prev_unit; + struct domain *d = v->domain; + + if ( (unit = xzalloc(struct sched_unit)) == NULL ) + return NULL; + + v->sched_unit = unit; + unit->vcpu = v; + + for ( prev_unit = &d->sched_unit_list; *prev_unit; + prev_unit = &(*prev_unit)->next_in_list ) + if ( (*prev_unit)->next_in_list && + (*prev_unit)->next_in_list->vcpu->vcpu_id > v->vcpu_id ) + break; + + unit->next_in_list = *prev_unit; + *prev_unit = unit; + + return unit; +} + int sched_init_vcpu(struct vcpu *v, unsigned int processor) { struct domain *d = v->domain; @@ -256,10 +302,8 @@ int sched_init_vcpu(struct vcpu *v, unsigned int processor) v->processor = processor; - if ( (unit = xzalloc(struct sched_unit)) == NULL ) + if ( (unit = sched_alloc_unit(v)) == NULL ) return 1; - v->sched_unit = unit; - unit->vcpu = v; /* Initialise the per-vcpu timers. */ init_timer(&v->periodic_timer, vcpu_periodic_timer_fn, @@ -272,8 +316,7 @@ int sched_init_vcpu(struct vcpu *v, unsigned int processor) unit->priv = sched_alloc_vdata(dom_scheduler(d), unit, d->sched_priv); if ( unit->priv == NULL ) { - v->sched_unit = NULL; - xfree(unit); + sched_free_unit(unit); return 1; } @@ -416,8 +459,7 @@ void sched_destroy_vcpu(struct vcpu *v) atomic_dec(&per_cpu(schedule_data, v->processor).urgent_count); sched_remove_unit(vcpu_scheduler(v), unit); sched_free_vdata(vcpu_scheduler(v), unit->priv); - xfree(unit); - v->sched_unit = NULL; + sched_free_unit(unit); } int sched_init_domain(struct domain *d, int poolid) diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h index f549ad60d1..4da1ab201d 100644 --- a/xen/include/xen/sched.h +++ b/xen/include/xen/sched.h @@ -279,8 +279,16 @@ struct vcpu struct sched_unit { struct vcpu *vcpu; void *priv; /* scheduler private data */ + struct sched_unit *next_in_list; }; +#define for_each_sched_unit(d, e) \ + for ( (e) = (d)->sched_unit_list; (e) != NULL; (e) = (e)->next_in_list ) + +#define for_each_sched_unit_vcpu(i, v) \ + for ( (v) = (i)->vcpu; (v) != NULL && (v)->sched_unit == (i); \ + (v) = (v)->next_in_list ) + /* Per-domain lock can be recursively acquired in fault handlers. */ #define domain_lock(d) spin_lock_recursive(&(d)->domain_lock) #define domain_unlock(d) spin_unlock_recursive(&(d)->domain_lock) @@ -339,6 +347,7 @@ struct domain /* Scheduling. */ void *sched_priv; /* scheduler-specific data */ + struct sched_unit *sched_unit_list; struct cpupool *cpupool; struct domain *next_in_list;