From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [net-next, RFC, 4/8] net: core: add recycle capabilities on skbs via page_pool API Date: Sat, 8 Dec 2018 04:34:15 -0800 Message-ID: <50266e0e-e2c6-efee-89d2-7518ee2761d0@gmail.com> References: <154413874729.21735.10644578158550468689.stgit@firesoul> <20181208095758.GA32028@strlen.de> <72f33f12-9222-cbe7-6ff2-e4b4f86fb17c@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, "David S. Miller" , =?UTF-8?Q?Toke_H=c3=b8iland-J=c3=b8rgensen?= , ard.biesheuvel@linaro.org, Jason Wang , ilias.apalodimas@linaro.org, =?UTF-8?B?QmrDtnJuVMO2cGVs?= , w@1wt.eu, Saeed Mahameed , mykyta.iziumtsev@gmail.com, Daniel Borkmann , Alexei Starovoitov , Tariq Toukan To: Florian Westphal , Jesper Dangaard Brouer Return-path: Received: from mail-pf1-f170.google.com ([209.85.210.170]:33454 "EHLO mail-pf1-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726121AbeLHMeS (ORCPT ); Sat, 8 Dec 2018 07:34:18 -0500 Received: by mail-pf1-f170.google.com with SMTP id c123so3229138pfb.0 for ; Sat, 08 Dec 2018 04:34:17 -0800 (PST) In-Reply-To: <72f33f12-9222-cbe7-6ff2-e4b4f86fb17c@gmail.com> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 12/08/2018 04:29 AM, Eric Dumazet wrote: > > But I do not get why the patch is needed. > > Adding extra cost for each skb destruction is costly. > > I though XDP was all about _not_ having skbs. > > Please let's do not slow down the non XDP stack only to make XDP more appealing. > I have a similar concern with napi_consume_skb() : This added a cost for locally generated TCP traffic, since most TX packets are fast clones.