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=-0.8 required=3.0 tests=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 1E4A4C10F14 for ; Tue, 8 Oct 2019 06:58:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E872820867 for ; Tue, 8 Oct 2019 06:58:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="iDg+l8uq" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730250AbfJHG6X (ORCPT ); Tue, 8 Oct 2019 02:58:23 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:39453 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730111AbfJHG6W (ORCPT ); Tue, 8 Oct 2019 02:58:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1570517901; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=BjiVfnfo3B219hJevj+nUA5nd9HYypooTjDbpxlfu2E=; b=iDg+l8uqsxGC0rzCjjSiN6614GKg+MM28ylegxN/Am9jp4g2RnYb3SZZyqeOrWjD5K6b3J dS+I8hjaLlaicPm56hIzKIJQjQ4WxddRYgXYf1U3jXNsq2q7CWP0wa2aeypPIvn2wXP30b eLo0ToVh79cHAT5Mj98DpOaywnaqExM= Received: from mail-lf1-f70.google.com (mail-lf1-f70.google.com [209.85.167.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-161-RIDzUwHTMYSQ8g4C3A3Mmg-1; Tue, 08 Oct 2019 02:58:20 -0400 Received: by mail-lf1-f70.google.com with SMTP id w193so2042465lff.3 for ; Mon, 07 Oct 2019 23:58:19 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:in-reply-to:references:date :message-id:mime-version; bh=S9PjHaofBE8WvE/gCT9+Hpu5GwookQh45Bj4/FXFqOI=; b=HcAvqarVCXH6xx0cnRTAcTrySM8HKeslcXDHU8fVrbxcB7ZyCkFIrVbMpircDpFWO1 iN17XT1FeYGBnlkRXXOqIRzkkwFp9cFwDRhQszEFCPd8H6crp5S7eWoVOoxQmQWwf2rt E9xNLEkE/FTSR4JTsv107C/yi8ZM9uGklMArC06E9seJYaX4lvXg2tDAw9sUKCIK7rV/ KcqIN9MwDLFI2nQMuBYDh0i40wbCwRwiKF7BK6JWMvC0GuVrWLMj5YW8tVQNxPNMVrvz +Fxl0LIbPD/H+KzW//nQ3Hx+EEtAf14MJIzs0ytZPD67U8m+yFn+2WbGvxoo7/7l4Cdi J23Q== X-Gm-Message-State: APjAAAWZRKcdRXm/6lNAsdo/IQof4xDn00IOzacthwiAYly2zuhOLd0L AIft9/zh8bT5wXZGx3aH+2dQU9NO53P/D1TcLZdfHAtAC+md6paNq/8UgecniQ86tSpiKtBhaq4 zlvKp8+aZ+Iif X-Received: by 2002:a2e:730a:: with SMTP id o10mr21912307ljc.214.1570517898816; Mon, 07 Oct 2019 23:58:18 -0700 (PDT) X-Google-Smtp-Source: APXvYqzcpPsm8E/3M1oXM5bmklENMw0tvOHJJmGog/AgsVSfuHgI1NlUp2BPNtR6+WN3vcVRbtaEPA== X-Received: by 2002:a2e:730a:: with SMTP id o10mr21912299ljc.214.1570517898646; Mon, 07 Oct 2019 23:58:18 -0700 (PDT) Received: from alrua-x1.borgediget.toke.dk ([2a00:7660:6da:443::2]) by smtp.gmail.com with ESMTPSA id b6sm3972837lfi.72.2019.10.07.23.58.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 07 Oct 2019 23:58:17 -0700 (PDT) Received: by alrua-x1.borgediget.toke.dk (Postfix, from userid 1000) id BF15F18063D; Tue, 8 Oct 2019 08:58:16 +0200 (CEST) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= To: Sridhar Samudrala , magnus.karlsson@intel.com, bjorn.topel@intel.com, netdev@vger.kernel.org, bpf@vger.kernel.org, sridhar.samudrala@intel.com, intel-wired-lan@lists.osuosl.org, maciej.fijalkowski@intel.com, tom.herbert@intel.com Subject: Re: [PATCH bpf-next 2/4] xsk: allow AF_XDP sockets to receive packets directly from a queue In-Reply-To: <1570515415-45593-3-git-send-email-sridhar.samudrala@intel.com> References: <1570515415-45593-1-git-send-email-sridhar.samudrala@intel.com> <1570515415-45593-3-git-send-email-sridhar.samudrala@intel.com> X-Clacks-Overhead: GNU Terry Pratchett Date: Tue, 08 Oct 2019 08:58:16 +0200 Message-ID: <875zkzn2pj.fsf@toke.dk> MIME-Version: 1.0 X-MC-Unique: RIDzUwHTMYSQ8g4C3A3Mmg-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Sridhar Samudrala writes: > int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, > =09=09 struct bpf_prog *xdp_prog) > { > =09struct bpf_redirect_info *ri =3D this_cpu_ptr(&bpf_redirect_info); > =09struct bpf_map *map =3D READ_ONCE(ri->map); > +=09struct xdp_sock *xsk; > + > +=09xsk =3D xdp_get_direct_xsk(ri); > +=09if (xsk) > +=09=09return xsk_rcv(xsk, xdp); This is a new branch and a read barrier in the XDP_REDIRECT fast path. What's the performance impact of that for non-XSK redirect? -Toke