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=-17.3 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,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 9973FC433E0 for ; Fri, 19 Feb 2021 14:39:36 +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 5CE2964D9A for ; Fri, 19 Feb 2021 14:39:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5CE2964D9A 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.86900.163433 (Exim 4.92) (envelope-from ) id 1lD6wE-0003Ak-1P; Fri, 19 Feb 2021 14:39:22 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 86900.163433; Fri, 19 Feb 2021 14:39:22 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lD6wD-0003Ad-Uk; Fri, 19 Feb 2021 14:39:21 +0000 Received: by outflank-mailman (input) for mailman id 86900; Fri, 19 Feb 2021 14:39:20 +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 4.92) (envelope-from ) id 1lD6wC-0003AY-2M for xen-devel@lists.xenproject.org; Fri, 19 Feb 2021 14:39:20 +0000 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 955d387b-96eb-448a-900d-52fc9ab7259e; Fri, 19 Feb 2021 14:39:18 +0000 (UTC) Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 2AFBAB10B; Fri, 19 Feb 2021 14:39:17 +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: 955d387b-96eb-448a-900d-52fc9ab7259e 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=1613745557; 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=lBZOODJxUXudV3lFWoXDl/wMzTDy0bjvGE3IRHW8zu4=; b=TtExeoZCT8EEi4bDTgzP87iroJMMZZZH/l2BxWK7Cj2n5gT882IY2JnEVE4fuYvI+Rj4L9 Mq09qQ6eD55C1RJ6UpfNJLjwtJvg69lW0+Jq94TRn5uhVMdf83ua925nJVU3YetKvkEJ4M PcWIZcFR2rjvFvsrdSo3/yuQBdBL81U= Subject: Re: [PATCH] x86/irq: simplify loop in unmap_domain_pirq To: Roger Pau Monne Cc: Andrew Cooper , Wei Liu , xen-devel@lists.xenproject.org References: <20210210092211.53359-1-roger.pau@citrix.com> From: Jan Beulich Message-ID: Date: Fri, 19 Feb 2021 15:39:14 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <20210210092211.53359-1-roger.pau@citrix.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit On 10.02.2021 10:22, Roger Pau Monne wrote: > The for loop in unmap_domain_pirq is unnecessary complicated, with > several places where the index is incremented, and also different > exit conditions spread between the loop body. > > Simplify it by looping over each possible PIRQ using the for loop > syntax, and remove all possible in-loop exit points. > > No functional change intended. > > Signed-off-by: Roger Pau Monné Reviewed-by: Jan Beulich Quite a bit better indeed. Just one nit below (can be taken care of while committing, once the tree will re-open). > @@ -2356,11 +2355,23 @@ int unmap_domain_pirq(struct domain *d, int pirq) > if ( msi_desc != NULL ) > pci_disable_msi(msi_desc); > > - spin_lock_irqsave(&desc->lock, flags); > - > - for ( i = 0; ; ) > + for ( i = 0; i < nr; i++, info = pirq_info(d, pirq + i) ) > { > + unsigned long flags; > + > + if ( !info || info->arch.irq <= 0 ) > + { > + printk(XENLOG_G_ERR "dom%d: MSI pirq %d not mapped\n", > + d->domain_id, pirq + i); %pd please as you touch/move this anyway. > @@ -2378,45 +2389,6 @@ int unmap_domain_pirq(struct domain *d, int pirq) > desc->msi_desc = NULL; > } > > - if ( ++i == nr ) > - break; > - > - spin_unlock_irqrestore(&desc->lock, flags); > - > - if ( !forced_unbind ) > - cleanup_domain_irq_pirq(d, irq, info); > - > - rc = irq_deny_access(d, irq); > - if ( rc ) > - { > - printk(XENLOG_G_ERR > - "dom%d: could not deny access to IRQ%d (pirq %d)\n", > - d->domain_id, irq, pirq + i); Looks like the pirq number logged here also was off by one, which the re-arrangement takes care of. Jan