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=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 66789C33CAC for ; Mon, 3 Feb 2020 12:11:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 393952082E for ; Mon, 3 Feb 2020 12:11:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Bxb38YHI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727267AbgBCMLo (ORCPT ); Mon, 3 Feb 2020 07:11:44 -0500 Received: from mail-qk1-f193.google.com ([209.85.222.193]:40785 "EHLO mail-qk1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727201AbgBCMLo (ORCPT ); Mon, 3 Feb 2020 07:11:44 -0500 Received: by mail-qk1-f193.google.com with SMTP id t204so13904510qke.7; Mon, 03 Feb 2020 04:11:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=PJ4qdO8JQggLc2fWQs+boqL64SksK4OFYeVmitKgQE4=; b=Bxb38YHIJX1vfVH2RKNljqr7dyt5Q/ki6AeGgnHvJ7uOngxB49ry89IdWx1kdg90B0 GUL7iyKw5dK8qSyARFnm5WazGUbUNcL+RhZjW0PLt33AoYRIAbPMNUNVk2EFECzaSse6 cs3zlPKhSYicpauAlaPnppQMfZGJI027iWqF+fbMnQyH49WfkGYrINVJ7VW0IlNpqwiS rirxMWUGsjIJT7hU3jM/KK/bGr+1LyPgcWyOhSNqpFYjKOeK4Env3C9EwHyDzVZn+RE+ 3LuENlU84kdtV3wbj7hTI6F0ndsbWJlLCkOz4C91+6usbO0dszlufk/rWNoscdOoliE7 Jf9Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=PJ4qdO8JQggLc2fWQs+boqL64SksK4OFYeVmitKgQE4=; b=T9U8fMvoP8Lk+PdT1cLSQitiVl8qo6sfjx30Zps78/3DIAxdmfcARea059kCCkpcdi UdVfF1mgYdFz9TduhZvWpWC0qa5c3yFQXVw42camNK8ROf7dbVc8cTHA0m/PKy/bNxyY 0xHueOOaANQpNzgmpqUerA2dp72LoiokFhKNt5507/MUusoOipU3o36tjvlRm7pAG+Zb MNhOXmcC7wsKSFITsmQK9DlHup8DfyauQ3xJex0bKJwpeytS2FWjEqwRDrzKDtVoa64w zlNmn+F9iKELG5/9G344Vw0Si0keqyxd+GF+XFM9JbU7V8xW/3bZLO32MtQ0p9jbBXeS bsNQ== X-Gm-Message-State: APjAAAXJR8RkRd8JD5nKFlRNaP5paZ8gQVfBy74VstEP2tJIrBJhJ39r eWlaaV7xiemcP8zHRXo573uzVbv62ssOso5ZQ/HYr9ibEVw= X-Google-Smtp-Source: APXvYqwe9Us2PgVu6MqeMNAO664AzntNtBV6pxz6hiw73jiD8G4iW8o+aobGl1EqwZofyiZhblcjvbiNbuP9RfonqcM= X-Received: by 2002:a37:9c0f:: with SMTP id f15mr23348389qke.297.1580731903294; Mon, 03 Feb 2020 04:11:43 -0800 (PST) MIME-Version: 1.0 References: <20191216091343.23260-1-bjorn.topel@gmail.com> <20191216091343.23260-8-bjorn.topel@gmail.com> In-Reply-To: From: =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= Date: Mon, 3 Feb 2020 13:11:32 +0100 Message-ID: Subject: Re: [PATCH bpf-next v2 7/9] riscv, bpf: optimize calls To: Palmer Dabbelt Cc: Daniel Borkmann , Alexei Starovoitov , Netdev , linux-riscv@lists.infradead.org, bpf Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Tue, 28 Jan 2020 at 03:15, Palmer Dabbelt wro= te: > [...] > > > > BPF passes arguments in R1, R2, ..., and return value in R0. Given > > that a0 plays the role of R1 and R0, how can we avoid the register > > juggling (without complicating the JIT too much)? It would be nice > > though... and ARM64 has the same concern AFAIK. > > Oh, why did you say that? This kind of stuff is why I'm twenty days behi= nd on > email... > > https://lore.kernel.org/bpf/20200128021145.36774-1-palmerdabbelt@google.c= om/T/#t > > :) > (back from vacation) :-D Very nice, I'll take a look! Bj=C3=B6rn