From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it0-f71.google.com (mail-it0-f71.google.com [209.85.214.71]) by kanga.kvack.org (Postfix) with ESMTP id 9E94B6B03C7 for ; Tue, 14 Feb 2017 14:02:03 -0500 (EST) Received: by mail-it0-f71.google.com with SMTP id 203so39665959ith.3 for ; Tue, 14 Feb 2017 11:02:03 -0800 (PST) Received: from mail-it0-x235.google.com (mail-it0-x235.google.com. [2607:f8b0:4001:c0b::235]) by mx.google.com with ESMTPS id i200si1732353ioi.119.2017.02.14.11.02.02 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 14 Feb 2017 11:02:02 -0800 (PST) Received: by mail-it0-x235.google.com with SMTP id c7so45698566itd.1 for ; Tue, 14 Feb 2017 11:02:02 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <20170214194615.3feddd07@redhat.com> References: <20170213195858.5215-1-edumazet@google.com> <20170213195858.5215-9-edumazet@google.com> <20170214131206.44b644f6@redhat.com> <20170214194615.3feddd07@redhat.com> From: Eric Dumazet Date: Tue, 14 Feb 2017 11:02:01 -0800 Message-ID: Subject: Re: [PATCH v3 net-next 08/14] mlx4: use order-0 pages for RX Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Jesper Dangaard Brouer Cc: Alexander Duyck , Tariq Toukan , "David S . Miller" , netdev , Tariq Toukan , Martin KaFai Lau , Saeed Mahameed , Willem de Bruijn , Brenden Blanco , Alexei Starovoitov , Eric Dumazet , linux-mm On Tue, Feb 14, 2017 at 10:46 AM, Jesper Dangaard Brouer wrote: > > > With this Intel driver page count based recycle approach, the recycle > size is tied to the size of the RX ring. As Eric and Tariq discovered. > And for other performance reasons (memory footprint of walking RX ring > data-structures), don't want to increase the RX ring sizes. Thus, it > create two opposite performance needs. That is why I think a more > explicit approach with a pool is more attractive. > > How is this approach doing to work for XDP? > (XDP doesn't "share" the page, and in-general we don't want the extra > atomic.) > > We absolutely need recycling with XDP, when transmitting out another > device, and the other devices DMA-TX completion need some way of > returning this page. > What is basically needed is a standardized callback to allow the remote > driver to return the page to the originating driver. As we don't have > a NDP for XDP-forward/transmit yet, we could pass this callback as a > parameter along with the packet-page to send? > > mlx4 already has a cache for XDP. I believe I did not change this part, it still should work. commit d576acf0a22890cf3f8f7a9b035f1558077f6770 Author: Brenden Blanco Date: Tue Jul 19 12:16:52 2016 -0700 net/mlx4_en: add page recycle to prepare rx ring for tx support I have not checked if recent Tom work added core infra for this cache. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org