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=-14.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 60F84C433E0 for ; Tue, 22 Dec 2020 10:11:13 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E6471207FF for ; Tue, 22 Dec 2020 10:11:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E6471207FF Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.57714.101068 (Exim 4.92) (envelope-from ) id 1kred4-0008Pv-AO; Tue, 22 Dec 2020 10:10:54 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 57714.101068; Tue, 22 Dec 2020 10:10:54 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1kred4-0008Po-7D; Tue, 22 Dec 2020 10:10:54 +0000 Received: by outflank-mailman (input) for mailman id 57714; Tue, 22 Dec 2020 10:10:52 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1kred2-0008Pj-Hi for xen-devel@lists.xenproject.org; Tue, 22 Dec 2020 10:10:52 +0000 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id a615acf8-f701-4429-98f0-24f599368e78; Tue, 22 Dec 2020 10:10:51 +0000 (UTC) Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id B5B6DAEE8; Tue, 22 Dec 2020 10:10:50 +0000 (UTC) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: a615acf8-f701-4429-98f0-24f599368e78 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1608631850; h=from:from:reply-to: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=jJJ28ty9NTTprw3dWv4SeSS337vWhUiTJofYzlDQAtI=; b=GqnQuB/82eEmobJJqHqQ3E6wenAc4SxsTvCGw8TGp3WBEeY0txDoZwUMdTJzdFfOfPMOhQ FdKrrcFurp52S1mKwcykRfl5rPPkab5ms1KnaIJWJJot+HE9xtecGpIuLHRVAEPZyNTYTz Q2iF+5E9D2m7lbnd+Sip/2B3rvmOW1s= Subject: Re: [PATCH 1/3] xen/domain: Reorder trivial initialisation in early domain_create() To: Andrew Cooper Cc: =?UTF-8?Q?Roger_Pau_Monn=c3=a9?= , Wei Liu , Stefano Stabellini , Julien Grall , Volodymyr Babchuk , Xen-devel References: <20201221181446.7791-1-andrew.cooper3@citrix.com> <20201221181446.7791-2-andrew.cooper3@citrix.com> From: Jan Beulich Message-ID: <3397707d-ba05-4db2-7dfd-e18dbe044a26@suse.com> Date: Tue, 22 Dec 2020 11:10:49 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: <20201221181446.7791-2-andrew.cooper3@citrix.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit On 21.12.2020 19:14, Andrew Cooper wrote: > --- a/xen/common/domain.c > +++ b/xen/common/domain.c > @@ -391,25 +391,7 @@ struct domain *domain_create(domid_t domid, > > TRACE_1D(TRC_DOM0_DOM_ADD, d->domain_id); > > - /* > - * Allocate d->vcpu[] and set ->max_vcpus up early. Various per-domain > - * resources want to be sized based on max_vcpus. > - */ > - if ( !is_system_domain(d) ) > - { > - err = -ENOMEM; > - d->vcpu = xzalloc_array(struct vcpu *, config->max_vcpus); > - if ( !d->vcpu ) > - goto fail; > - > - d->max_vcpus = config->max_vcpus; > - } > - > - lock_profile_register_struct(LOCKPROF_TYPE_PERDOM, d, domid); Wouldn't this also count as "trivial initialization", and hence while moving want to at least be placed ... > - if ( (err = xsm_alloc_security_domain(d)) != 0 ) > - goto fail; > - > + /* Trivial initialisation. */ > atomic_set(&d->refcnt, 1); > RCU_READ_LOCK_INIT(&d->rcu_lock); > spin_lock_init_prof(d, domain_lock); > @@ -434,6 +416,27 @@ struct domain *domain_create(domid_t domid, > INIT_LIST_HEAD(&d->pdev_list); > #endif > > + /* All error paths can depend on the above setup. */ ... ahead of this comment? > + /* > + * Allocate d->vcpu[] and set ->max_vcpus up early. Various per-domain > + * resources want to be sized based on max_vcpus. > + */ > + if ( !is_system_domain(d) ) > + { > + err = -ENOMEM; > + d->vcpu = xzalloc_array(struct vcpu *, config->max_vcpus); > + if ( !d->vcpu ) > + goto fail; > + > + d->max_vcpus = config->max_vcpus; > + } > + > + lock_profile_register_struct(LOCKPROF_TYPE_PERDOM, d, domid); > + > + if ( (err = xsm_alloc_security_domain(d)) != 0 ) > + goto fail; > + > err = -ENOMEM; > if ( !zalloc_cpumask_var(&d->dirty_cpumask) ) > goto fail; > Just as an observation (i.e. unlikely for this patch) I doubt system domains need ->dirty_cpumask set up, and hence this allocation may also want moving down a few lines. Jan