From patchwork Tue Nov 7 20:59:34 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Taht X-Patchwork-Id: 835466 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@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; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="RDEu/6tV"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3yWhdP00hKz9s8J for ; Wed, 8 Nov 2017 07:59:52 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933657AbdKGU7q (ORCPT ); Tue, 7 Nov 2017 15:59:46 -0500 Received: from mail-pf0-f196.google.com ([209.85.192.196]:49533 "EHLO mail-pf0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933644AbdKGU7p (ORCPT ); Tue, 7 Nov 2017 15:59:45 -0500 Received: by mail-pf0-f196.google.com with SMTP id i5so386381pfe.6 for ; Tue, 07 Nov 2017 12:59:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=5jHTdYxzmw/Ha6kzzwNtj+24hoU72A9flrbyjepVZSI=; b=RDEu/6tVIidkQ7HQIaRcjmBG+hr8xZCZE+tWIctXjl/+HO2nDienR+sQtO/K5cR00p CHLYuTU7o/ZgLV9vKheE0pfyUOuSFX0AK5fg11vCZkSFQBf1z8GHbSFQwLyGC/z2THjg 7TVZ2ujZQdDaF+QCKO4ptW6X7ekN2jckHnI1aUB5NGEZAiSQhBK8vVys68zODFe9UaRT 25/L0fZq9EKCKP04vHVfwBVFJyCTqGJiqgrqf+53mZZ6qM2JLBQKXlFlLCvUyNbz31RP CiVfMG+lobs/fGyueU5hpqUrLP9RavAjL2WfnGcYWiz09ePP4mQzlSKyY6j68WRsUAqn SNkQ== 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:in-reply-to :references; bh=5jHTdYxzmw/Ha6kzzwNtj+24hoU72A9flrbyjepVZSI=; b=MlLzarbg505UxBN5Uk1BcE15pLlao2nG4BVugoc5l8JdfKMrUM8anxPKh6sLgtIjqq rN43nzQZgopPNyLegVJ3HGb1sGmIkB3D9zfzZVCx0fzpM8KniwmOhoYEWkJQyH9bh4hi XFfc8MFe8EfUoQxgS1DfodBE4yA0Y7yiqoXdf4OrnlFjRqejkfsTArwah8JeNV3fQDgp HHDJe/p/ItPA2jGeGyR76GeFMjq5T1OS1oe+KF/9X/lPt+6+6JaLFhFetpQV/ObeDPpp X6woEPSNEyESiZxUN7ttqGmYBaLp1nXxosGBDMY7GTtHjwKjGMofwaUxz7NlZTKiHxqo 3Ywg== X-Gm-Message-State: AJaThX6P03Rhl5eEqKo+qgPxH+bAIMcGymSRLmoDxo2aag8fgPxOP2jK iELdD0mFd6j48aCmdAv7P4SMoQ== X-Google-Smtp-Source: ABhQp+TfMvmIMasKt6AaMczHuB4TNs1GFMuhUZAV6hrAIGRamVwPH8q69aJJIDVGDKmdb28vR8sT7g== X-Received: by 10.84.177.131 with SMTP id x3mr18863plb.327.1510088384212; Tue, 07 Nov 2017 12:59:44 -0800 (PST) Received: from nemesis.lab.teklibre.com ([2603:3024:1536:86f0:2e0:4cff:fec1:1206]) by smtp.gmail.com with ESMTPSA id a81sm4548104pfe.32.2017.11.07.12.59.43 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 07 Nov 2017 12:59:43 -0800 (PST) From: Dave Taht To: netdev@vger.kernel.org Cc: Dave Taht Subject: [PATCH net-next 1/3] netem: convert to qdisc_watchdog_schedule_ns Date: Tue, 7 Nov 2017 12:59:34 -0800 Message-Id: <1510088376-5527-2-git-send-email-dave.taht@gmail.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1510088376-5527-1-git-send-email-dave.taht@gmail.com> References: <1510088376-5527-1-git-send-email-dave.taht@gmail.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Upgrade the internal netem scheduler to use nanoseconds rather than ticks throughout. Convert to and from the std "ticks" userspace api automatically, while allowing for finer grained scheduling to take place. Signed-off-by: Dave Taht --- net/sched/sch_netem.c | 56 +++++++++++++++++++++++++-------------------------- 1 file changed, 28 insertions(+), 28 deletions(-) diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c index db0228a..443a75d 100644 --- a/net/sched/sch_netem.c +++ b/net/sched/sch_netem.c @@ -77,8 +77,8 @@ struct netem_sched_data { struct qdisc_watchdog watchdog; - psched_tdiff_t latency; - psched_tdiff_t jitter; + s64 latency; + s64 jitter; u32 loss; u32 ecn; @@ -145,7 +145,7 @@ struct netem_sched_data { * we save skb->tstamp value in skb->cb[] before destroying it. */ struct netem_skb_cb { - psched_time_t time_to_send; + u64 time_to_send; }; static inline struct netem_skb_cb *netem_skb_cb(struct sk_buff *skb) @@ -305,11 +305,11 @@ static bool loss_event(struct netem_sched_data *q) * std deviation sigma. Uses table lookup to approximate the desired * distribution, and a uniformly-distributed pseudo-random source. */ -static psched_tdiff_t tabledist(psched_tdiff_t mu, psched_tdiff_t sigma, - struct crndstate *state, - const struct disttable *dist) +static s64 tabledist(s64 mu, s64 sigma, + struct crndstate *state, + const struct disttable *dist) { - psched_tdiff_t x; + s64 x; long t; u32 rnd; @@ -332,10 +332,10 @@ static psched_tdiff_t tabledist(psched_tdiff_t mu, psched_tdiff_t sigma, return x / NETEM_DIST_SCALE + (sigma / NETEM_DIST_SCALE) * t + mu; } -static psched_time_t packet_len_2_sched_time(unsigned int len, struct netem_sched_data *q) +static s64 packet_len_2_sched_time(unsigned int len, + struct netem_sched_data *q) { - u64 ticks; - + s64 offset; len += q->packet_overhead; if (q->cell_size) { @@ -345,11 +345,9 @@ static psched_time_t packet_len_2_sched_time(unsigned int len, struct netem_sche cells++; len = cells * (q->cell_size + q->cell_overhead); } - - ticks = (u64)len * NSEC_PER_SEC; - - do_div(ticks, q->rate); - return PSCHED_NS2TICKS(ticks); + offset = (s64)len * NSEC_PER_SEC; + do_div(offset, q->rate); + return offset; } static void tfifo_reset(struct Qdisc *sch) @@ -369,7 +367,7 @@ static void tfifo_reset(struct Qdisc *sch) static void tfifo_enqueue(struct sk_buff *nskb, struct Qdisc *sch) { struct netem_sched_data *q = qdisc_priv(sch); - psched_time_t tnext = netem_skb_cb(nskb)->time_to_send; + u64 tnext = netem_skb_cb(nskb)->time_to_send; struct rb_node **p = &q->t_root.rb_node, *parent = NULL; while (*p) { @@ -515,13 +513,13 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch, if (q->gap == 0 || /* not doing reordering */ q->counter < q->gap - 1 || /* inside last reordering gap */ q->reorder < get_crandom(&q->reorder_cor)) { - psched_time_t now; - psched_tdiff_t delay; + u64 now; + s64 delay; delay = tabledist(q->latency, q->jitter, &q->delay_cor, q->delay_dist); - now = psched_get_time(); + now = ktime_get_ns(); if (q->rate) { struct netem_skb_cb *last = NULL; @@ -547,7 +545,7 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch, * from delay. */ delay -= last->time_to_send - now; - delay = max_t(psched_tdiff_t, 0, delay); + delay = max_t(s64, 0, delay); now = last->time_to_send; } @@ -562,7 +560,7 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch, * Do re-ordering by putting one out of N packets at the front * of the queue. */ - cb->time_to_send = psched_get_time(); + cb->time_to_send = ktime_get_ns(); q->counter = 0; netem_enqueue_skb_head(&sch->q, skb); @@ -609,13 +607,13 @@ static struct sk_buff *netem_dequeue(struct Qdisc *sch) } p = rb_first(&q->t_root); if (p) { - psched_time_t time_to_send; + u64 time_to_send; skb = rb_to_skb(p); /* if more time remaining? */ time_to_send = netem_skb_cb(skb)->time_to_send; - if (time_to_send <= psched_get_time()) { + if (time_to_send <= ktime_get_ns()) { rb_erase(p, &q->t_root); sch->q.qlen--; @@ -659,7 +657,7 @@ static struct sk_buff *netem_dequeue(struct Qdisc *sch) if (skb) goto deliver; } - qdisc_watchdog_schedule(&q->watchdog, time_to_send); + qdisc_watchdog_schedule_ns(&q->watchdog, time_to_send); } if (q->qdisc) { @@ -888,8 +886,8 @@ static int netem_change(struct Qdisc *sch, struct nlattr *opt) sch->limit = qopt->limit; - q->latency = qopt->latency; - q->jitter = qopt->jitter; + q->latency = PSCHED_TICKS2NS(qopt->latency); + q->jitter = PSCHED_TICKS2NS(qopt->jitter); q->limit = qopt->limit; q->gap = qopt->gap; q->counter = 0; @@ -1011,8 +1009,10 @@ static int netem_dump(struct Qdisc *sch, struct sk_buff *skb) struct tc_netem_corrupt corrupt; struct tc_netem_rate rate; - qopt.latency = q->latency; - qopt.jitter = q->jitter; + qopt.latency = min_t(psched_tdiff_t, PSCHED_NS2TICKS(q->latency), + UINT_MAX); + qopt.jitter = min_t(psched_tdiff_t, PSCHED_NS2TICKS(q->jitter), + UINT_MAX); qopt.limit = q->limit; qopt.loss = q->loss; qopt.gap = q->gap; From patchwork Tue Nov 7 20:59:35 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Taht X-Patchwork-Id: 835465 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@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; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="UHhHzaG8"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3yWhdK24FHz9s8J for ; Wed, 8 Nov 2017 07:59:49 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933664AbdKGU7s (ORCPT ); Tue, 7 Nov 2017 15:59:48 -0500 Received: from mail-pf0-f193.google.com ([209.85.192.193]:46070 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933309AbdKGU7p (ORCPT ); Tue, 7 Nov 2017 15:59:45 -0500 Received: by mail-pf0-f193.google.com with SMTP id d28so395715pfe.2 for ; Tue, 07 Nov 2017 12:59:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=vaNhS7uY2ypjJQKyRQqES97fiBO6vZt/sgGNx0eC5rI=; b=UHhHzaG8I1G7+/KIs40qE9Va9PzGqpOT3Yk271seoa/932D/MEqXbZoZk1lrkJ55Qu 2oJzeN8rfCZOO3eezOYUCWMBVdzrRob9QpI9UmsLSFoUpRQCxqf3kSqq2zMfm/41+7YG TD2Le6fjUa3L+/5yaBdlsOpM/AU8P0ZasyumpLmNnrJPLgaEZB+Eeu9thQFpPU5rA7O9 ClCIK4pnUuAZB2nYgg9eF3IYoJNgMZo1tiJph755mKM5PB7jmHJfGKmONy0tYGguy+5N Q0L0ax7zZF3Z7y0czucjO0OrFh0vPPGnIQXouN/wTeTpx6F6Em5tZhifNwmTM3h601+n unJA== 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:in-reply-to :references; bh=vaNhS7uY2ypjJQKyRQqES97fiBO6vZt/sgGNx0eC5rI=; b=EsCzlFviZWWLZJEffYC6j+9dCNlZFDklF6ysIcnGK8ZMWyeBQ91BvvuwpNPcHASmi/ JXDZ7AlTlem8GcfEqmlO8qIDp2XeR7np9X/JFaiEAbKp3S1djIpaFNZvVG5I3XEoSx/Y ciyL8glzp3KeiUXkzxlgCrAuvYxDSOB+2mcjz5ctRLKSFT8FrCwT5UVujUdB3IMcksQ0 UBlM3mcju4HKS8N7jn9KSFkOoiR70Y+HZcQ2xp35JcWp+JwZDL4dKN8mTNv0HMTWjXMI EhMumKjib1OVYpxYn+Fl+VnUdUsKNaAFn8ToTQ+ql2tEj+1n4Fs243wmBV0z5TCm54P8 MDsw== X-Gm-Message-State: AJaThX4D2fzj34yck9zwSquutyfmie0eYgKOpU9cCBGbb95m5iNm/mmO 6s1Z2q0XKrDSoB1bZiH3OyZ1IA== X-Google-Smtp-Source: ABhQp+TZRY/LCu/gD0OnJpdrO+cY4V7Wta+jgRBJ82oMifJ2kCyjR5tOol4rRVELC6gEBRFL2zoKAw== X-Received: by 10.159.252.7 with SMTP id n7mr17676pls.355.1510088385139; Tue, 07 Nov 2017 12:59:45 -0800 (PST) Received: from nemesis.lab.teklibre.com ([2603:3024:1536:86f0:2e0:4cff:fec1:1206]) by smtp.gmail.com with ESMTPSA id a81sm4548104pfe.32.2017.11.07.12.59.44 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 07 Nov 2017 12:59:44 -0800 (PST) From: Dave Taht To: netdev@vger.kernel.org Cc: Dave Taht Subject: [PATCH net-next 2/3] netem: add uapi to express delay and jitter in nanosec Date: Tue, 7 Nov 2017 12:59:35 -0800 Message-Id: <1510088376-5527-3-git-send-email-dave.taht@gmail.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1510088376-5527-1-git-send-email-dave.taht@gmail.com> References: <1510088376-5527-1-git-send-email-dave.taht@gmail.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org netem userspace has long relied on a horrible /proc/net/psched hack to translate the current notion of "ticks" to nanoseconds. Expressing latency and jitter instead, in well defined nanoseconds, increases the dynamic range of emulated delays and jitter in netem. It will also ease a transition where reducing a tick to nsec equivalence would constrain the max delay in prior versions of netem to only 4.3 seconds. Signed-off-by: Dave Taht --- include/uapi/linux/pkt_sched.h | 2 ++ net/sched/sch_netem.c | 16 ++++++++++++++++ 2 files changed, 18 insertions(+) diff --git a/include/uapi/linux/pkt_sched.h b/include/uapi/linux/pkt_sched.h index 5002562..20cfd64 100644 --- a/include/uapi/linux/pkt_sched.h +++ b/include/uapi/linux/pkt_sched.h @@ -536,6 +536,8 @@ enum { TCA_NETEM_ECN, TCA_NETEM_RATE64, TCA_NETEM_PAD, + TCA_NETEM_LATENCY64, + TCA_NETEM_JITTER64, __TCA_NETEM_MAX, }; diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c index 443a75d..16c4813 100644 --- a/net/sched/sch_netem.c +++ b/net/sched/sch_netem.c @@ -819,6 +819,8 @@ static const struct nla_policy netem_policy[TCA_NETEM_MAX + 1] = { [TCA_NETEM_LOSS] = { .type = NLA_NESTED }, [TCA_NETEM_ECN] = { .type = NLA_U32 }, [TCA_NETEM_RATE64] = { .type = NLA_U64 }, + [TCA_NETEM_LATENCY64] = { .type = NLA_S64 }, + [TCA_NETEM_JITTER64] = { .type = NLA_S64 }, }; static int parse_attr(struct nlattr *tb[], int maxtype, struct nlattr *nla, @@ -916,6 +918,12 @@ static int netem_change(struct Qdisc *sch, struct nlattr *opt) q->rate = max_t(u64, q->rate, nla_get_u64(tb[TCA_NETEM_RATE64])); + if (tb[TCA_NETEM_LATENCY64]) + q->latency = nla_get_s64(tb[TCA_NETEM_LATENCY64]); + + if (tb[TCA_NETEM_JITTER64]) + q->jitter = nla_get_s64(tb[TCA_NETEM_JITTER64]); + if (tb[TCA_NETEM_ECN]) q->ecn = nla_get_u32(tb[TCA_NETEM_ECN]); @@ -1020,6 +1028,14 @@ static int netem_dump(struct Qdisc *sch, struct sk_buff *skb) if (nla_put(skb, TCA_OPTIONS, sizeof(qopt), &qopt)) goto nla_put_failure; + if (PSCHED_TICKS2NS(qopt.latency) != q->latency) + if (nla_put(skb, TCA_NETEM_LATENCY64, sizeof(q->latency), + &q->latency)) + goto nla_put_failure; + if (PSCHED_TICKS2NS(qopt.jitter) != q->jitter) + if (nla_put(skb, TCA_NETEM_JITTER64, sizeof(q->jitter), + &q->jitter)) + goto nla_put_failure; cor.delay_corr = q->delay_cor.rho; cor.loss_corr = q->loss_cor.rho; cor.dup_corr = q->dup_cor.rho; From patchwork Tue Nov 7 20:59:36 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Taht X-Patchwork-Id: 835467 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; 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Tue, 07 Nov 2017 12:59:46 -0800 (PST) Received: from nemesis.lab.teklibre.com ([2603:3024:1536:86f0:2e0:4cff:fec1:1206]) by smtp.gmail.com with ESMTPSA id a81sm4548104pfe.32.2017.11.07.12.59.45 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 07 Nov 2017 12:59:45 -0800 (PST) From: Dave Taht To: netdev@vger.kernel.org Cc: Dave Taht Subject: [PATCH net-next 3/3] netem: support delivering packets in delayed time slots Date: Tue, 7 Nov 2017 12:59:36 -0800 Message-Id: <1510088376-5527-4-git-send-email-dave.taht@gmail.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1510088376-5527-1-git-send-email-dave.taht@gmail.com> References: <1510088376-5527-1-git-send-email-dave.taht@gmail.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Slotting is a crude approximation of the behaviors of shared media such as cable, wifi, and LTE, which gather up a bunch of packets within a varying delay window and deliver them, relative to that, nearly all at once. It works within the existing loss, duplication, jitter and delay parameters of netem. Some amount of inherent latency must be specified, regardless. The new "slot" parameter specifies a minimum and maximum delay between transmission attempts. The "bytes" and "packets" parameters can be used to limit the amount of information transferred per slot. Examples of use: tc qdisc add dev eth0 root netem delay 200us \ slot 800us 10ms bytes 64k packets 42 A more correct example, using stacked netem instances and a packet limit to emulate a tail drop wifi queue with slots and variable packet delivery, with a 200Mbit isochronous underlying rate, and 20ms path delay: tc qdisc add dev eth0 root handle 1: netem delay 20ms rate 200mbit \ limit 10000 tc qdisc add dev eth0 parent 1:1 handle 10:1 netem delay 200us \ slot 800us 10ms bytes 64k packets 42 limit 512 Signed-off-by: Dave Taht --- include/uapi/linux/pkt_sched.h | 8 +++++ net/sched/sch_netem.c | 76 ++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 81 insertions(+), 3 deletions(-) diff --git a/include/uapi/linux/pkt_sched.h b/include/uapi/linux/pkt_sched.h index 20cfd64..37b5096 100644 --- a/include/uapi/linux/pkt_sched.h +++ b/include/uapi/linux/pkt_sched.h @@ -538,6 +538,7 @@ enum { TCA_NETEM_PAD, TCA_NETEM_LATENCY64, TCA_NETEM_JITTER64, + TCA_NETEM_SLOT, __TCA_NETEM_MAX, }; @@ -575,6 +576,13 @@ struct tc_netem_rate { __s32 cell_overhead; }; +struct tc_netem_slot { + __s64 min_delay; /* nsec */ + __s64 max_delay; + __s32 max_packets; + __s32 max_bytes; +}; + enum { NETEM_LOSS_UNSPEC, NETEM_LOSS_GI, /* General Intuitive - 4 state model */ diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c index 16c4813..a7189f9 100644 --- a/net/sched/sch_netem.c +++ b/net/sched/sch_netem.c @@ -135,6 +135,13 @@ struct netem_sched_data { u32 a5; /* p23 used only in 4-states */ } clg; + struct tc_netem_slot slot_config; + struct slotstate { + u64 slot_next; + s32 packets_left; + s32 bytes_left; + } slot; + }; /* Time stamp put into socket buffer control block @@ -591,6 +598,20 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch, return NET_XMIT_SUCCESS; } +/* Delay the next round with a new future slot with a + * correct number of bytes and packets. + */ + +static void get_slot_next(struct netem_sched_data *q, u64 now) +{ + q->slot.slot_next = now + q->slot_config.min_delay + + (prandom_u32() * + (q->slot_config.max_delay - + q->slot_config.min_delay) >> 32); + q->slot.packets_left = q->slot_config.max_packets; + q->slot.bytes_left = q->slot_config.max_bytes; +} + static struct sk_buff *netem_dequeue(struct Qdisc *sch) { struct netem_sched_data *q = qdisc_priv(sch); @@ -608,14 +629,17 @@ static struct sk_buff *netem_dequeue(struct Qdisc *sch) p = rb_first(&q->t_root); if (p) { u64 time_to_send; + u64 now = ktime_get_ns(); skb = rb_to_skb(p); /* if more time remaining? */ time_to_send = netem_skb_cb(skb)->time_to_send; - if (time_to_send <= ktime_get_ns()) { - rb_erase(p, &q->t_root); + if (q->slot.slot_next && q->slot.slot_next < time_to_send) + get_slot_next(q, now); + if (time_to_send <= now && q->slot.slot_next <= now) { + rb_erase(p, &q->t_root); sch->q.qlen--; qdisc_qstats_backlog_dec(sch, skb); skb->next = NULL; @@ -634,6 +658,14 @@ static struct sk_buff *netem_dequeue(struct Qdisc *sch) skb->tstamp = 0; #endif + if (q->slot.slot_next) { + q->slot.packets_left--; + q->slot.bytes_left -= qdisc_pkt_len(skb); + if (q->slot.packets_left <= 0 || + q->slot.bytes_left <= 0) + get_slot_next(q, now); + } + if (q->qdisc) { unsigned int pkt_len = qdisc_pkt_len(skb); struct sk_buff *to_free = NULL; @@ -657,7 +689,12 @@ static struct sk_buff *netem_dequeue(struct Qdisc *sch) if (skb) goto deliver; } - qdisc_watchdog_schedule_ns(&q->watchdog, time_to_send); + + if (q->slot.slot_next > now) + qdisc_watchdog_schedule_ns(&q->watchdog, + q->slot.slot_next); + else + qdisc_watchdog_schedule_ns(&q->watchdog, time_to_send); } if (q->qdisc) { @@ -688,6 +725,7 @@ static void dist_free(struct disttable *d) * Distribution data is a variable size payload containing * signed 16 bit values. */ + static int get_dist_table(struct Qdisc *sch, const struct nlattr *attr) { struct netem_sched_data *q = qdisc_priv(sch); @@ -718,6 +756,23 @@ static int get_dist_table(struct Qdisc *sch, const struct nlattr *attr) return 0; } +static void get_slot(struct netem_sched_data *q, const struct nlattr *attr) +{ + const struct tc_netem_slot *c = nla_data(attr); + + q->slot_config = *c; + if (q->slot_config.max_packets == 0) + q->slot_config.max_packets = INT_MAX; + if (q->slot_config.max_bytes == 0) + q->slot_config.max_bytes = INT_MAX; + q->slot.packets_left = q->slot_config.max_packets; + q->slot.bytes_left = q->slot_config.max_bytes; + if (q->slot_config.min_delay | q->slot_config.max_delay) + q->slot.slot_next = ktime_get_ns(); + else + q->slot.slot_next = 0; +} + static void get_correlation(struct netem_sched_data *q, const struct nlattr *attr) { const struct tc_netem_corr *c = nla_data(attr); @@ -821,6 +876,7 @@ static const struct nla_policy netem_policy[TCA_NETEM_MAX + 1] = { [TCA_NETEM_RATE64] = { .type = NLA_U64 }, [TCA_NETEM_LATENCY64] = { .type = NLA_S64 }, [TCA_NETEM_JITTER64] = { .type = NLA_S64 }, + [TCA_NETEM_SLOT] = { .len = sizeof(struct tc_netem_slot) }, }; static int parse_attr(struct nlattr *tb[], int maxtype, struct nlattr *nla, @@ -927,6 +983,9 @@ static int netem_change(struct Qdisc *sch, struct nlattr *opt) if (tb[TCA_NETEM_ECN]) q->ecn = nla_get_u32(tb[TCA_NETEM_ECN]); + if (tb[TCA_NETEM_SLOT]) + get_slot(q, tb[TCA_NETEM_SLOT]); + return ret; } @@ -1016,6 +1075,7 @@ static int netem_dump(struct Qdisc *sch, struct sk_buff *skb) struct tc_netem_reorder reorder; struct tc_netem_corrupt corrupt; struct tc_netem_rate rate; + struct tc_netem_slot slot; qopt.latency = min_t(psched_tdiff_t, PSCHED_NS2TICKS(q->latency), UINT_MAX); @@ -1072,6 +1132,16 @@ static int netem_dump(struct Qdisc *sch, struct sk_buff *skb) if (dump_loss_model(q, skb) != 0) goto nla_put_failure; + if (q->slot_config.min_delay | q->slot_config.max_delay) { + slot = q->slot_config; + if (slot.max_packets == INT_MAX) + slot.max_packets = 0; + if (slot.max_bytes == INT_MAX) + slot.max_bytes = 0; + if (nla_put(skb, TCA_NETEM_SLOT, sizeof(slot), &slot)) + goto nla_put_failure; + } + return nla_nest_end(skb, nla); nla_put_failure: