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=-17.2 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,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 215F2C433ED for ; Thu, 8 Apr 2021 12:20:39 +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 CB11261041 for ; Thu, 8 Apr 2021 12:20:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CB11261041 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.107252.205037 (Exim 4.92) (envelope-from ) id 1lUTe8-0004hh-TW; Thu, 08 Apr 2021 12:20:28 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 107252.205037; Thu, 08 Apr 2021 12:20:28 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lUTe8-0004ha-QT; Thu, 08 Apr 2021 12:20:28 +0000 Received: by outflank-mailman (input) for mailman id 107252; Thu, 08 Apr 2021 12:20:28 +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 1lUTe7-0004hC-Td for xen-devel@lists.xenproject.org; Thu, 08 Apr 2021 12:20:27 +0000 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 1d3974a3-264d-4372-88fd-dc6326da25d9; Thu, 08 Apr 2021 12:20:27 +0000 (UTC) Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 4B643B0E6; Thu, 8 Apr 2021 12:20:26 +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: 1d3974a3-264d-4372-88fd-dc6326da25d9 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=1617884426; 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=dQLFBbZwmFP7/XJISrFVWgSoZI+0nr2VJyf5BHmRMeA=; b=RQDKsL8zp4IN2ANmpnNqpG1LhduC6Z/nnT4q7+7JgHelBGhZIr6M0yByjuuC8Ph7W8mJ9V oPV3r7z7s+N1Q0dkGgzcX2sB1ANp69zW0VJJJ4Nr961S+nvIq2jY5IKHJhAjJO6+tw+Knh t3+gkgweDp2Qwj4X+28vF2CmHkiiiXo= Subject: [PATCH 06/11] x86/IRQ: avoid over-alignment in alloc_pirq_struct() From: Jan Beulich To: "xen-devel@lists.xenproject.org" Cc: Andrew Cooper , George Dunlap , Wei Liu , =?UTF-8?Q?Roger_Pau_Monn=c3=a9?= References: Message-ID: <75885e8f-fd0a-5ac1-b194-7f8858320874@suse.com> Date: Thu, 8 Apr 2021 14:20:26 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.9.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit In particular in the PV case xzalloc_bytes() forcing SMP_CACHE_BYTES alignment is counterproductive, as the allocation size there is only 40 bytes. Signed-off-by: Jan Beulich --- a/xen/arch/x86/irq.c +++ b/xen/arch/x86/irq.c @@ -1313,9 +1313,12 @@ void cleanup_domain_irq_mapping(struct d struct pirq *alloc_pirq_struct(struct domain *d) { - size_t sz = is_hvm_domain(d) ? sizeof(struct pirq) : - offsetof(struct pirq, arch.hvm); - struct pirq *pirq = xzalloc_bytes(sz); + union pirq_pv { + char space[offsetof(struct pirq, arch.hvm)]; + void *align; + }; + struct pirq *pirq = is_hvm_domain(d) ? xzalloc(struct pirq) + : (void *)xzalloc(union pirq_pv); if ( pirq ) {