From patchwork Fri Apr 5 13:01:59 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: 1078389 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 44bKj40lkpz9sPM for ; Sat, 6 Apr 2019 00:02:15 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726730AbfDENCO (ORCPT ); Fri, 5 Apr 2019 09:02:14 -0400 Received: from mail-ed1-f67.google.com ([209.85.208.67]:46414 "EHLO mail-ed1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726027AbfDENCO (ORCPT ); Fri, 5 Apr 2019 09:02:14 -0400 Received: by mail-ed1-f67.google.com with SMTP id d1so5394940edd.13 for ; Fri, 05 Apr 2019 06:02:13 -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:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=G1UzkJ43GQJs++bOOlkUYoC9ekVSWSjs27zcD1DZTxE=; b=RZQsMRqyaxRcM1BppuAK6/MaePR2lc4IqBc3aE7w7sgEcsGlL/XWt6C48rfsrHt5Co qSdGPrW3dirwnt0DrIL49ngQHtpAvTK04sXDJFuiCXZqK40af/j7zfOt3QNTefg0tXZW pTc1iKE9ayZvjTQZXqzfe5ADLFgCk5F2OYHG1yMIbDxj2dag1FKUMEQfRQ5ZEKYPyy2A yJBGEyPU3LO6uZ/c86EPEZoQsBrYnKjEfY4gD9kqmQOFCl5fOfeaqitmqW8ERiiRo5hO NqLxCSEwHc3MjVBitp0fhlIosqCMps7rGwMavo2iSa/te562n1MtJ3BP4Vwa9rB+oWEv TM9w== X-Gm-Message-State: APjAAAX5Hs+78I+PmWt87RwycDV/LFvmtU1w6U3mcKPzmFw5lYeSxXew OQh7K4WaQJhxwUNNuYwikZfnOg== X-Google-Smtp-Source: APXvYqxGhkcbpaFfMOOj3gMOfIbd7FWvijDBYr7srUNm7AVEtsXntSLnzS0u/+Q8gHH1sMZwY2scUw== X-Received: by 2002:a17:906:b84c:: with SMTP id ga12mr6859336ejb.253.1554469332465; Fri, 05 Apr 2019 06:02:12 -0700 (PDT) Received: from alrua-x1.borgediget.toke.dk (alrua-x1.vpn.toke.dk. [2a00:7660:6da:10::2]) by smtp.gmail.com with ESMTPSA id y4sm6345843edq.53.2019.04.05.06.02.11 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 05 Apr 2019 06:02:11 -0700 (PDT) Received: by alrua-x1.borgediget.toke.dk (Postfix, from userid 1000) id 4D6C91804A5; Fri, 5 Apr 2019 15:02:11 +0200 (CEST) From: =?utf-8?q?Toke_H=C3=B8iland-J=C3=B8rgensen?= To: davem@davemloft.net Cc: netdev@vger.kernel.org, =?utf-8?q?Toke_H=C3=B8iland-J=C3=B8rgensen?= , Kevin Darbyshire-Bryant Subject: [PATCH for-stable] sch_cake: Simplify logic in cake_select_tin() Date: Fri, 5 Apr 2019 15:01:59 +0200 Message-Id: <20190405130159.13059-1-toke@redhat.com> X-Mailer: git-send-email 2.21.0 MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org commit 4b454433221de445f6d3d73b0ac27b4f7da25b83 upstream. The logic in cake_select_tin() was getting a bit hairy, and it turns out we can 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 --- This is a backported version of the upstream patch, that should apply to 5.0 and 4.19 and make the other two sch_cake patches queued up for stable apply as-is on top. net/sched/sch_cake.c | 44 ++++++++++++++++---------------------------- 1 file changed, 16 insertions(+), 28 deletions(-) diff --git a/net/sched/sch_cake.c b/net/sched/sch_cake.c index 793016d722ec..640f00e9f665 100644 --- a/net/sched/sch_cake.c +++ b/net/sched/sch_cake.c @@ -1508,20 +1508,6 @@ 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; @@ -1553,25 +1539,27 @@ 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 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->tin_mode == CAKE_DIFFSERV_BESTEFFORT) + tin = 0; + + 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]; - if (q->rate_flags & CAKE_FLAG_WASH) - cake_wash_diffserv(skb); - } else if (q->tin_mode != CAKE_DIFFSERV_BESTEFFORT) { - /* 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)]; + else { + tin = q->tin_index[dscp]; + if (unlikely(tin >= q->tin_cnt)) tin = 0; - } else { - tin = 0; - if (q->rate_flags & CAKE_FLAG_WASH) - cake_wash_diffserv(skb); } return &q->tins[tin];