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=-7.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 528AAC04EB8 for ; Mon, 10 Dec 2018 17:10:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1373220821 for ; Mon, 10 Dec 2018 17:10:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="RxaNN9iQ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1373220821 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=oracle.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728091AbeLJRKH (ORCPT ); Mon, 10 Dec 2018 12:10:07 -0500 Received: from userp2130.oracle.com ([156.151.31.86]:51872 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727356AbeLJRKH (ORCPT ); Mon, 10 Dec 2018 12:10:07 -0500 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.22/8.16.0.22) with SMTP id wBAH9Vrk056230; Mon, 10 Dec 2018 17:09:57 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : to : cc : references : from : message-id : date : mime-version : in-reply-to : content-type : content-transfer-encoding; s=corp-2018-07-02; bh=9Qhk1Zm2iUha5mKf95eBfiEwbjgmLqYHH2B4/tm++sE=; b=RxaNN9iQ7h3uC8ewIqza/5iCQOmfEwQ+q51mgxqO2x4f2B6QxbgvH4EO5at/WnK6PZv4 K8E1NgmOZ+6bes05hesYGnH/ryuP/im9lc4bgJVh1/0TCcfN8i1F4pql6c2yl3yZ207U /ZpyIskfyQYfc7W2gF6w4n2mUnrjgG6ECpLuKaL2pIqMoBh/I94mr/ruUK/Em397rcod rVnC8Pn5bUdBFQPq30KgAkXfXFLEIbQVAcSu21wfpzY3+npgjBs55XtH57D9KdhwGqkn o5o9UUEySsp2R44x5wyeXE1EmEpGURvX8fpByf/QfGwNYsyK4dwcpj68VZDOWB8VDdl2 qQ== Received: from userv0022.oracle.com (userv0022.oracle.com [156.151.31.74]) by userp2130.oracle.com with ESMTP id 2p85cty8t0-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 10 Dec 2018 17:09:57 +0000 Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by userv0022.oracle.com (8.14.4/8.14.4) with ESMTP id wBAH9uMi027585 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 10 Dec 2018 17:09:56 GMT Received: from abhmp0009.oracle.com (abhmp0009.oracle.com [141.146.116.15]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id wBAH9uaE014743; Mon, 10 Dec 2018 17:09:56 GMT Received: from [10.211.47.70] (/10.211.47.70) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 10 Dec 2018 09:09:55 -0800 Subject: Re: [PATCH v2 2/2] swiotlb: checking whether swiotlb buffer is full with io_tlb_used To: Dongli Zhang , iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org Cc: konrad.wilk@oracle.com, hch@lst.de, m.szyprowski@samsung.com, robin.murphy@arm.com References: <1544402278-8175-1-git-send-email-dongli.zhang@oracle.com> <1544402278-8175-2-git-send-email-dongli.zhang@oracle.com> From: Joe Jin Message-ID: <912321c7-5f27-bfec-b4d9-3d50efeed356@oracle.com> Date: Mon, 10 Dec 2018 09:09:55 -0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <1544402278-8175-2-git-send-email-dongli.zhang@oracle.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9103 signatures=668679 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=2 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1812100154 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/9/18 4:37 PM, Dongli Zhang wrote: > This patch uses io_tlb_used to help check whether swiotlb buffer is full. > io_tlb_used is no longer used for only debugfs. It is also used to help > optimize swiotlb_tbl_map_single(). > > Suggested-by: Joe Jin > Signed-off-by: Dongli Zhang Reviewed-by: Joe Jin > --- > kernel/dma/swiotlb.c | 10 ++++------ > 1 file changed, 4 insertions(+), 6 deletions(-) > > diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c > index 3979c2c..9300341 100644 > --- a/kernel/dma/swiotlb.c > +++ b/kernel/dma/swiotlb.c > @@ -76,12 +76,10 @@ static phys_addr_t io_tlb_start, io_tlb_end; > */ > static unsigned long io_tlb_nslabs; > > -#ifdef CONFIG_DEBUG_FS > /* > * The number of used IO TLB block > */ > static unsigned long io_tlb_used; > -#endif > > /* > * This is a free list describing the number of free entries available from > @@ -489,6 +487,10 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, > * request and allocate a buffer from that IO TLB pool. > */ > spin_lock_irqsave(&io_tlb_lock, flags); > + > + if (unlikely(nslots > io_tlb_nslabs - io_tlb_used)) > + goto not_found; > + > index = ALIGN(io_tlb_index, stride); > if (index >= io_tlb_nslabs) > index = 0; > @@ -538,9 +540,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, > dev_warn(hwdev, "swiotlb buffer is full (sz: %zd bytes)\n", size); > return SWIOTLB_MAP_ERROR; > found: > -#ifdef CONFIG_DEBUG_FS > io_tlb_used += nslots; > -#endif > spin_unlock_irqrestore(&io_tlb_lock, flags); > > /* > @@ -602,9 +602,7 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, > for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE -1) && io_tlb_list[i]; i--) > io_tlb_list[i] = ++count; > > -#ifdef CONFIG_DEBUG_FS > io_tlb_used -= nslots; > -#endif > } > spin_unlock_irqrestore(&io_tlb_lock, flags); > } > -- Oracle Joe Jin | Software Development Director ORACLE | Linux and Virtualization 500 Oracle Parkway Redwood City, CA US 94065