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=-3.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 63803C433E3 for ; Fri, 10 Jul 2020 13:27:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 34906207BB for ; Fri, 10 Jul 2020 13:27:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ZTvIS/3V" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727871AbgGJN1O (ORCPT ); Fri, 10 Jul 2020 09:27:14 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:21381 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726774AbgGJN1N (ORCPT ); Fri, 10 Jul 2020 09:27:13 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594387632; 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=8A/1vpEmoSOyHkkH6nhIq0DHvbGeWI2fZCwGb0gKD0U=; b=ZTvIS/3VgfJzVLdZ1stwoHBYKFNEg5QV99BbNE1BSIougrfBUdecwRkF56iqjdNVtwObVI +rlBsqpjHeCrA40FCxLACT/dmZBWEMD7T7NqCUreOl16K2eZ7PjKU9HrW4F5Wl5W3bHjSS b2kCnU8gO2MYr5qOqBNiZYfejnP/sY4= 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-354-iB5ik_0TPn-3lfedhmvmhg-1; Fri, 10 Jul 2020 09:27:10 -0400 X-MC-Unique: iB5ik_0TPn-3lfedhmvmhg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 447AB1092; Fri, 10 Jul 2020 13:27:08 +0000 (UTC) Received: from carbon (unknown [10.40.208.42]) by smtp.corp.redhat.com (Postfix) with ESMTP id ACAD478A4B; Fri, 10 Jul 2020 13:27:00 +0000 (UTC) Date: Fri, 10 Jul 2020 15:26:58 +0200 From: Jesper Dangaard Brouer To: Christoph Hellwig Cc: iommu@lists.linux-foundation.org, Alexey Kardashevskiy , linuxppc-dev@lists.ozlabs.org, Lu Baolu , Greg Kroah-Hartman , Joerg Roedel , Robin Murphy , =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , Daniel Borkmann , linux-kernel@vger.kernel.org, brouer@redhat.com Subject: Re: generic DMA bypass flag v4 Message-ID: <20200710152658.31a9391a@carbon> In-Reply-To: <20200708152449.316476-1-hch@lst.de> References: <20200708152449.316476-1-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 8 Jul 2020 17:24:44 +0200 Christoph Hellwig wrote: > Note that as-is this breaks the XSK buffer pool, which unfortunately > poked directly into DMA internals. A fix for that is already queued > up in the netdev tree. >=20 > Jesper and XDP gang: this should not regress any performance as > the dma-direct calls are now inlined into the out of line DMA mapping > calls. But if you can verify the performance numbers that would be > greatly appreciated. =46rom a superficial review of the patches, they look okay to me. I don't have time to run a performance benchmark (before I go on vacation). I hoped Bj=C3=B6rn could test/benchmark this(?), given (as mentioned) this also affect XSK / AF_XDP performance. --=20 Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer