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 Received: from smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 54E08C433EF for ; Thu, 30 Jun 2022 12:14:40 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id F2A2340DC2; Thu, 30 Jun 2022 12:14:39 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org F2A2340DC2 X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id gD7XwpmXGHh8; Thu, 30 Jun 2022 12:14:39 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by smtp2.osuosl.org (Postfix) with ESMTPS id DB42840AC0; Thu, 30 Jun 2022 12:14:38 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org DB42840AC0 Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id B5B78C0021; Thu, 30 Jun 2022 12:14:38 +0000 (UTC) Received: from smtp3.osuosl.org (smtp3.osuosl.org [140.211.166.136]) by lists.linuxfoundation.org (Postfix) with ESMTP id 840D0C0011 for ; Thu, 30 Jun 2022 12:14:37 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id 5141C61350 for ; Thu, 30 Jun 2022 12:14:37 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp3.osuosl.org 5141C61350 X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id dNLq3N1O3SxF for ; Thu, 30 Jun 2022 12:14:36 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp3.osuosl.org 8CB4B61339 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by smtp3.osuosl.org (Postfix) with ESMTPS id 8CB4B61339 for ; Thu, 30 Jun 2022 12:14:36 +0000 (UTC) Received: from fraeml711-chm.china.huawei.com (unknown [172.18.147.207]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4LYcbp2794z6878R; Thu, 30 Jun 2022 20:10:30 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml711-chm.china.huawei.com (10.206.15.60) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 30 Jun 2022 14:14:34 +0200 Received: from localhost.localdomain (10.69.192.58) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 30 Jun 2022 13:14:30 +0100 To: , , , , , , , Subject: [PATCH v5 4/5] scsi: scsi_transport_sas: Cap shost max_sectors according to DMA optimal limit Date: Thu, 30 Jun 2022 20:08:11 +0800 Message-ID: <1656590892-42307-5-git-send-email-john.garry@huawei.com> X-Mailer: git-send-email 2.8.1 In-Reply-To: <1656590892-42307-1-git-send-email-john.garry@huawei.com> References: <1656590892-42307-1-git-send-email-john.garry@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.69.192.58] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Cc: linux-scsi@vger.kernel.org, linux-doc@vger.kernel.org, linuxarm@huawei.com, iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org, iommu@lists.linux-foundation.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: John Garry via iommu Reply-To: John Garry Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Streaming DMA mappings may be considerably slower when mappings go through an IOMMU and the total mapping length is somewhat long. This is because the IOMMU IOVA code allocates and free an IOVA for each mapping, which may affect performance. For performance reasons set the request queue max_sectors from dma_opt_mapping_size(), which knows this mapping limit. Signed-off-by: John Garry --- drivers/scsi/scsi_transport_sas.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/scsi/scsi_transport_sas.c b/drivers/scsi/scsi_transport_sas.c index 12bff64dade6..1b45248748e0 100644 --- a/drivers/scsi/scsi_transport_sas.c +++ b/drivers/scsi/scsi_transport_sas.c @@ -225,6 +225,7 @@ static int sas_host_setup(struct transport_container *tc, struct device *dev, { struct Scsi_Host *shost = dev_to_shost(dev); struct sas_host_attrs *sas_host = to_sas_host_attrs(shost); + struct device *dma_dev = shost->dma_dev; INIT_LIST_HEAD(&sas_host->rphy_list); mutex_init(&sas_host->lock); @@ -236,6 +237,11 @@ static int sas_host_setup(struct transport_container *tc, struct device *dev, dev_printk(KERN_ERR, dev, "fail to a bsg device %d\n", shost->host_no); + if (dma_dev) { + shost->max_sectors = min_t(unsigned int, shost->max_sectors, + dma_opt_mapping_size(dma_dev) >> SECTOR_SHIFT); + } + return 0; } -- 2.35.3 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9E19B7B for ; Thu, 30 Jun 2022 12:14:36 +0000 (UTC) Received: from fraeml711-chm.china.huawei.com (unknown [172.18.147.207]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4LYcbp2794z6878R; Thu, 30 Jun 2022 20:10:30 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml711-chm.china.huawei.com (10.206.15.60) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 30 Jun 2022 14:14:34 +0200 Received: from localhost.localdomain (10.69.192.58) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 30 Jun 2022 13:14:30 +0100 From: John Garry To: , , , , , , , CC: , , , , , , , John Garry Subject: [PATCH v5 4/5] scsi: scsi_transport_sas: Cap shost max_sectors according to DMA optimal limit Date: Thu, 30 Jun 2022 20:08:11 +0800 Message-ID: <1656590892-42307-5-git-send-email-john.garry@huawei.com> X-Mailer: git-send-email 2.8.1 In-Reply-To: <1656590892-42307-1-git-send-email-john.garry@huawei.com> References: <1656590892-42307-1-git-send-email-john.garry@huawei.com> Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.69.192.58] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Message-ID: <20220630120811.-o-ItgEWQxBPI30a5UzLU2kXZUbcDC4jxyTVvNyYqV8@z> Streaming DMA mappings may be considerably slower when mappings go through an IOMMU and the total mapping length is somewhat long. This is because the IOMMU IOVA code allocates and free an IOVA for each mapping, which may affect performance. For performance reasons set the request queue max_sectors from dma_opt_mapping_size(), which knows this mapping limit. Signed-off-by: John Garry --- drivers/scsi/scsi_transport_sas.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/scsi/scsi_transport_sas.c b/drivers/scsi/scsi_transport_sas.c index 12bff64dade6..1b45248748e0 100644 --- a/drivers/scsi/scsi_transport_sas.c +++ b/drivers/scsi/scsi_transport_sas.c @@ -225,6 +225,7 @@ static int sas_host_setup(struct transport_container *tc, struct device *dev, { struct Scsi_Host *shost = dev_to_shost(dev); struct sas_host_attrs *sas_host = to_sas_host_attrs(shost); + struct device *dma_dev = shost->dma_dev; INIT_LIST_HEAD(&sas_host->rphy_list); mutex_init(&sas_host->lock); @@ -236,6 +237,11 @@ static int sas_host_setup(struct transport_container *tc, struct device *dev, dev_printk(KERN_ERR, dev, "fail to a bsg device %d\n", shost->host_no); + if (dma_dev) { + shost->max_sectors = min_t(unsigned int, shost->max_sectors, + dma_opt_mapping_size(dma_dev) >> SECTOR_SHIFT); + } + return 0; } -- 2.35.3