From patchwork Fri Mar 1 15:04:05 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Toke_H=C3=B8iland-J=C3=B8rgensen?= X-Patchwork-Id: 1050240 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 449t46608nz9sCJ for ; Sat, 2 Mar 2019 02:04:22 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388450AbfCAPEP (ORCPT ); Fri, 1 Mar 2019 10:04:15 -0500 Received: from mail-ed1-f67.google.com ([209.85.208.67]:35949 "EHLO mail-ed1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727492AbfCAPEL (ORCPT ); Fri, 1 Mar 2019 10:04:11 -0500 Received: by mail-ed1-f67.google.com with SMTP id g9so20284110eds.3 for ; Fri, 01 Mar 2019 07:04:09 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:from:to:cc:date:message-id:in-reply-to :references:user-agent:mime-version:content-transfer-encoding; bh=aRmYNjoO1dPSs5MsBsHcSaNCGSXe7pIvdShAD0RX3L4=; b=gA0qGXy+RQe3/T7wfm8vTdnNLqhG6EJq93wKmtZKt411F6yIFCUVfB2EWjChrvNJAs ZXtW8gfIH59Rm3EB785dcrT6zL18M/5YWSgNk24Q3JJ9nWFUiVB14wVq7A39qn8M27s+ KKlypOa+DCMAPXOGCjLAviMeOzCwMkXHv6lrUBT52JcUQarIkFTQJJZhUAXIhIQ3PTsb oTDhtHFKB5gaezuexSTymjBO9LMP3iQLOIccEF1WKzJXVXa+XEI8Vjo/5fFIaGFTb+w9 1MCUlYc++nCabIwfbgpvp3+VvKrHermxVqe5Iet6uP57YEVUeQk+07AuwcKVf7uk9PGP AZCA== X-Gm-Message-State: APjAAAW8JJRevKnbq9d3sZUmOu+BvuiI+UbBh5um/mJmBNVnylEZgJzj JB2h3xR3vzV8+TDOafb9rAIFWw== X-Google-Smtp-Source: APXvYqysGuj21YquJCkOwyg6p+GSDSXwDnvJJuyNAla4daYYrckFj28Q7ZUCrRYNMJJLUhxyR0QsJA== X-Received: by 2002:a17:906:3496:: with SMTP id g22mr3357324ejb.193.1551452648940; Fri, 01 Mar 2019 07:04:08 -0800 (PST) Received: from alrua-x1.borgediget.toke.dk (borgediget.toke.dk. [85.204.121.218]) by smtp.gmail.com with ESMTPSA id y45sm5990624edd.33.2019.03.01.07.04.06 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 01 Mar 2019 07:04:06 -0800 (PST) Received: by alrua-x1.borgediget.toke.dk (Postfix, from userid 1000) id CFDF8183BC5; Fri, 1 Mar 2019 16:04:05 +0100 (CET) Subject: [PATCH net-next v1 3/3] sch_cake: Simplify logic in cake_select_tin() From: Toke =?utf-8?q?H=C3=B8iland-J=C3=B8rgensen?= To: David Miller Cc: netdev@vger.kernel.org, cake@lists.bufferbloat.net Date: Fri, 01 Mar 2019 16:04:05 +0100 Message-ID: <155145264579.2564.12320265553780481623.stgit@alrua-x1> In-Reply-To: <155145264557.2564.18246059144961803752.stgit@alrua-x1> References: <155145264557.2564.18246059144961803752.stgit@alrua-x1> User-Agent: StGit/unknown-version MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Toke Høiland-Jørgensen With more modes added the logic in cake_select_tin() was getting a bit hairy, and it turns out we can actually simplify it quite a bit. This also allows us to get rid of one of the two diffserv parsing functions, which has the added benefit that already-zeroed DSCP fields won't get re-written. Suggested-by: Kevin Darbyshire-Bryant Signed-off-by: Toke Høiland-Jørgensen --- net/sched/sch_cake.c | 61 +++++++++++++++++++------------------------------- 1 file changed, 23 insertions(+), 38 deletions(-) diff --git a/net/sched/sch_cake.c b/net/sched/sch_cake.c index f1cc4779699b..1d2a12132abc 100644 --- a/net/sched/sch_cake.c +++ b/net/sched/sch_cake.c @@ -1513,20 +1513,6 @@ static unsigned int cake_drop(struct Qdisc *sch, struct sk_buff **to_free) return idx + (tin << 16); } -static void cake_wash_diffserv(struct sk_buff *skb) -{ - switch (skb->protocol) { - case htons(ETH_P_IP): - ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, 0); - break; - case htons(ETH_P_IPV6): - ipv6_change_dsfield(ipv6_hdr(skb), INET_ECN_MASK, 0); - break; - default: - break; - } -} - static u8 cake_handle_diffserv(struct sk_buff *skb, u16 wash) { u8 dscp; @@ -1558,33 +1544,32 @@ static struct cake_tin_data *cake_select_tin(struct Qdisc *sch, { struct cake_sched_data *q = qdisc_priv(sch); u32 tin; + u8 dscp; - if (TC_H_MAJ(skb->priority) == sch->handle && - TC_H_MIN(skb->priority) > 0 && - TC_H_MIN(skb->priority) <= q->tin_cnt) { - tin = q->tin_order[TC_H_MIN(skb->priority) - 1]; + /* Tin selection: Default to diffserv-based selection, allow overriding + * using firewall marks or skb->priority. + */ + dscp = cake_handle_diffserv(skb, + q->rate_flags & CAKE_FLAG_WASH); - if (q->rate_flags & CAKE_FLAG_WASH) - cake_wash_diffserv(skb); - } else if (q->tin_mode != CAKE_DIFFSERV_BESTEFFORT) { - if (q->rate_flags & CAKE_FLAG_FWMARK && /* use fw mark */ - skb->mark && - skb->mark <= q->tin_cnt) { - tin = q->tin_order[skb->mark - 1]; - if (q->rate_flags & CAKE_FLAG_WASH) - cake_wash_diffserv(skb); - } else { - /* extract the Diffserv Precedence field, if it exists */ - /* and clear DSCP bits if washing */ - tin = q->tin_index[cake_handle_diffserv(skb, - q->rate_flags & CAKE_FLAG_WASH)]; - if (unlikely(tin >= q->tin_cnt)) - tin = 0; - } - } else { + if (q->tin_mode == CAKE_DIFFSERV_BESTEFFORT) tin = 0; - if (q->rate_flags & CAKE_FLAG_WASH) - cake_wash_diffserv(skb); + + else if (q->rate_flags & CAKE_FLAG_FWMARK && /* use fw mark */ + skb->mark && + skb->mark <= q->tin_cnt) + tin = q->tin_order[skb->mark - 1]; + + else if (TC_H_MAJ(skb->priority) == sch->handle && + TC_H_MIN(skb->priority) > 0 && + TC_H_MIN(skb->priority) <= q->tin_cnt) + tin = q->tin_order[TC_H_MIN(skb->priority) - 1]; + + else { + tin = q->tin_index[dscp]; + + if (unlikely(tin >= q->tin_cnt)) + tin = 0; } return &q->tins[tin];