From patchwork Wed Mar 10 10:45:00 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Beulich X-Patchwork-Id: 12127695 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,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 36743C433E0 for ; Wed, 10 Mar 2021 10:45:15 +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 CBEDC64FE8 for ; Wed, 10 Mar 2021 10:45:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CBEDC64FE8 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.95982.181303 (Exim 4.92) (envelope-from ) id 1lJwKt-0003gG-Kx; Wed, 10 Mar 2021 10:45:03 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 95982.181303; Wed, 10 Mar 2021 10:45:03 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lJwKt-0003g9-Ht; Wed, 10 Mar 2021 10:45:03 +0000 Received: by outflank-mailman (input) for mailman id 95982; Wed, 10 Mar 2021 10:45:02 +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 1lJwKs-0003g1-Qu for xen-devel@lists.xenproject.org; Wed, 10 Mar 2021 10:45:02 +0000 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 07f34e48-b43f-4b95-9233-6c324fcba987; Wed, 10 Mar 2021 10:45:01 +0000 (UTC) Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id BEE2DAC24; Wed, 10 Mar 2021 10:45:00 +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: 07f34e48-b43f-4b95-9233-6c324fcba987 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=1615373100; 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=auDrX8MZ83gAoUw+7BpRkycrdv7LFLuKqOyiZSwy028=; b=U6KSOMYSnqdrAhjabRmOrA8sANDOgTUDp0Tcij6mADEbEb8k2sN2Xes4fS4yeXaQhPMTX1 48jmJGbBAuGb/qRlX86u20JXvII8RsZQlZMKCNChd0N6rZp2J4LPc8yG/QuzLFLt2WFgLM zq9/iT1sue4pokc+jwjl+LbrAMwyICE= Subject: [PATCH 1/3] Xen/gntdev: don't needlessly allocate k{,un}map_ops[] From: Jan Beulich To: Juergen Gross , Boris Ostrovsky , Stefano Stabellini Cc: "xen-devel@lists.xenproject.org" References: <2b326dc6-c624-c97b-f9c4-4cc68dd013ba@suse.com> Message-ID: <180d50cb-5531-8952-4bf0-d65c554638ed@suse.com> Date: Wed, 10 Mar 2021 11:45:00 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.8.0 MIME-Version: 1.0 In-Reply-To: <2b326dc6-c624-c97b-f9c4-4cc68dd013ba@suse.com> Content-Language: en-US They're needed only in the not-auto-translate (i.e. PV) case; there's no point in allocating memory that's never going to get accessed. Signed-off-by: Jan Beulich Reviewed-by: Juergen Gross --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -136,17 +136,20 @@ struct gntdev_grant_map *gntdev_alloc_ma add->grants = kvcalloc(count, sizeof(add->grants[0]), GFP_KERNEL); add->map_ops = kvcalloc(count, sizeof(add->map_ops[0]), GFP_KERNEL); add->unmap_ops = kvcalloc(count, sizeof(add->unmap_ops[0]), GFP_KERNEL); - add->kmap_ops = kvcalloc(count, sizeof(add->kmap_ops[0]), GFP_KERNEL); - add->kunmap_ops = kvcalloc(count, - sizeof(add->kunmap_ops[0]), GFP_KERNEL); add->pages = kvcalloc(count, sizeof(add->pages[0]), GFP_KERNEL); if (NULL == add->grants || NULL == add->map_ops || NULL == add->unmap_ops || - NULL == add->kmap_ops || - NULL == add->kunmap_ops || NULL == add->pages) goto err; + if (use_ptemod) { + add->kmap_ops = kvcalloc(count, sizeof(add->kmap_ops[0]), + GFP_KERNEL); + add->kunmap_ops = kvcalloc(count, sizeof(add->kunmap_ops[0]), + GFP_KERNEL); + if (NULL == add->kmap_ops || NULL == add->kunmap_ops) + goto err; + } #ifdef CONFIG_XEN_GRANT_DMA_ALLOC add->dma_flags = dma_flags; @@ -185,8 +188,10 @@ struct gntdev_grant_map *gntdev_alloc_ma for (i = 0; i < count; i++) { add->map_ops[i].handle = -1; add->unmap_ops[i].handle = -1; - add->kmap_ops[i].handle = -1; - add->kunmap_ops[i].handle = -1; + if (use_ptemod) { + add->kmap_ops[i].handle = -1; + add->kunmap_ops[i].handle = -1; + } } add->index = 0; @@ -332,8 +337,8 @@ int gntdev_map_grant_pages(struct gntdev } pr_debug("map %d+%d\n", map->index, map->count); - err = gnttab_map_refs(map->map_ops, use_ptemod ? map->kmap_ops : NULL, - map->pages, map->count); + err = gnttab_map_refs(map->map_ops, map->kmap_ops, map->pages, + map->count); for (i = 0; i < map->count; i++) { if (map->map_ops[i].status == GNTST_okay)