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=-7.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_PASS,USER_AGENT_MUTT autolearn=unavailable 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 80741C64EB1 for ; Sat, 8 Dec 2018 16:51:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 504012081C for ; Sat, 8 Dec 2018 16:51:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 504012081C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de 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 S1726290AbeLHQvB (ORCPT ); Sat, 8 Dec 2018 11:51:01 -0500 Received: from verein.lst.de ([213.95.11.211]:40737 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726172AbeLHQvA (ORCPT ); Sat, 8 Dec 2018 11:51:00 -0500 Received: by newverein.lst.de (Postfix, from userid 2407) id D906168AA6; Sat, 8 Dec 2018 17:50:58 +0100 (CET) Date: Sat, 8 Dec 2018 17:50:58 +0100 From: Christoph Hellwig To: Jesper Dangaard Brouer Cc: Christoph Hellwig , iommu@lists.linux-foundation.org, Linus Torvalds , Tariq Toukan , Ilias Apalodimas , Toke =?iso-8859-1?Q?H=F8iland-J=F8rgensen?= , Robin Murphy , Konrad Rzeszutek Wilk , Tony Luck , Fenghua Yu , Marek Szyprowski , Keith Busch , Jonathan Derrick , linux-pci@vger.kernel.org, linux-ia64@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [RFC] avoid indirect calls for DMA direct mappings v2 Message-ID: <20181208165058.GA14874@lst.de> References: <20181207190720.18517-1-hch@lst.de> <20181208170648.296fb8a1@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181208170648.296fb8a1@redhat.com> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Dec 08, 2018 at 05:06:48PM +0100, Jesper Dangaard Brouer wrote: > You can add my: > Tested-by: Jesper Dangaard Brouer > or > Acked-by: Jesper Dangaard Brouer > > I'm very happy that you work on this. And I've done micro-benchmark > testing of the patchset (and branch dma-direct-calls), which I've made > avail here: > https://github.com/xdp-project/xdp-project/blob/master/areas/dma/dma01_test_hellwig_direct_dma.org > > My XDP performance is back, minus the BPF-indirect call, and > net_rx_action napi->poll, and net_device->ndo_xdp_xmit calls. I > verified that manually disabling retpoline for these remaining netstack > retpoline-calls restore the performance full (well minus 1.5 nanosec). Thanks a lot for all the testing (and the initial report). I'd love to still gets this in for 4.21 if we can, but for that I'd need a lot more folks to carefull review it, especially the swiotlb and ia64 bits. So if we don't get that early next week I feel we might have to punt it to the next merge window.