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,DKIMWL_WL_HIGH, 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,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 DA247C433FE for ; Mon, 7 Dec 2020 04:02:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A0CE2223E0 for ; Mon, 7 Dec 2020 04:02:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728561AbgLGEB5 (ORCPT ); Sun, 6 Dec 2020 23:01:57 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:46588 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726483AbgLGEB5 (ORCPT ); Sun, 6 Dec 2020 23:01:57 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1607313630; h=from:from:reply-to:subject:subject: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=xNjTsielO4F3/rlOTAeVEcwEo4ih/pfIX8Fxa5vfASY=; b=WUuCyscMV/0uDf1w7m0rjckAcT7G1C7Cc9Eu0v0L9mGmCeWEavnLWeVmstO5+KSyzf10Ex k7zjr6PSzTGKzPWuqlXntAKsnqul4pMBexKbioq1bpvvsvuedH5u+olmMIaxyY5cZlcr3C pnrNKfjwCRxoKERo+GN03ui6u5imI/w= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-93-fGf-jxRoOX-zOv3r-DnZCg-1; Sun, 06 Dec 2020 23:00:29 -0500 X-MC-Unique: fGf-jxRoOX-zOv3r-DnZCg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5A61581CAF6; Mon, 7 Dec 2020 04:00:27 +0000 (UTC) Received: from [10.72.13.171] (ovpn-13-171.pek2.redhat.com [10.72.13.171]) by smtp.corp.redhat.com (Postfix) with ESMTP id AA2A25C1BB; Mon, 7 Dec 2020 04:00:08 +0000 (UTC) Subject: Re: [PATCH v3 05/19] vdpa_sim: remove the limit of IOTLB entries To: Stefano Garzarella , virtualization@lists.linux-foundation.org Cc: Stefan Hajnoczi , "Michael S. Tsirkin" , Oren Duer , Laurent Vivier , linux-kernel@vger.kernel.org, Max Gurtovoy , Shahaf Shuler , Eli Cohen References: <20201203170511.216407-1-sgarzare@redhat.com> <20201203170511.216407-6-sgarzare@redhat.com> From: Jason Wang Message-ID: Date: Mon, 7 Dec 2020 12:00:07 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20201203170511.216407-6-sgarzare@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020/12/4 上午1:04, Stefano Garzarella wrote: > The simulated devices can support multiple queues, so this limit > should be defined according to the number of queues supported by > the device. > > Since we are in a simulator, let's simply remove that limit. > > Suggested-by: Jason Wang > Acked-by: Jason Wang > Signed-off-by: Stefano Garzarella Rethink about this, since simulator can be used by VM, so the allocation is actually guest trigger-able when vIOMMU is enabled. This means we need a limit somehow, (e.g I remember swiotlb is about 64MB by default). Or having a module parameter for this. Btw, have you met any issue when using 2048, I guess it can happen when we run several processes in parallel? > --- > v3: > - used VHOST_IOTLB_UNLIMITED macro [Jason] > v2: > - added VDPASIM_IOTLB_LIMIT macro [Jason] > --- > drivers/vdpa/vdpa_sim/vdpa_sim.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c > index 295a770caac0..688aceaa6543 100644 > --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c > +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c > @@ -368,7 +368,7 @@ static struct vdpasim *vdpasim_create(void) > if (!vdpasim->vqs) > goto err_iommu; > > - vdpasim->iommu = vhost_iotlb_alloc(2048, 0); > + vdpasim->iommu = vhost_iotlb_alloc(VHOST_IOTLB_UNLIMITED, 0); > if (!vdpasim->iommu) > goto err_iommu; >