12874c5fdSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later 2585d763aSVinicius Costa Gomes /* 3585d763aSVinicius Costa Gomes * net/sched/sch_cbs.c Credit Based Shaper 4585d763aSVinicius Costa Gomes * 5585d763aSVinicius Costa Gomes * Authors: Vinicius Costa Gomes <vinicius.gomes@intel.com> 6585d763aSVinicius Costa Gomes */ 7585d763aSVinicius Costa Gomes 8585d763aSVinicius Costa Gomes /* Credit Based Shaper (CBS) 9585d763aSVinicius Costa Gomes * ========================= 10585d763aSVinicius Costa Gomes * 11585d763aSVinicius Costa Gomes * This is a simple rate-limiting shaper aimed at TSN applications on 12585d763aSVinicius Costa Gomes * systems with known traffic workloads. 13585d763aSVinicius Costa Gomes * 14585d763aSVinicius Costa Gomes * Its algorithm is defined by the IEEE 802.1Q-2014 Specification, 15585d763aSVinicius Costa Gomes * Section 8.6.8.2, and explained in more detail in the Annex L of the 16585d763aSVinicius Costa Gomes * same specification. 17585d763aSVinicius Costa Gomes * 18585d763aSVinicius Costa Gomes * There are four tunables to be considered: 19585d763aSVinicius Costa Gomes * 20585d763aSVinicius Costa Gomes * 'idleslope': Idleslope is the rate of credits that is 21585d763aSVinicius Costa Gomes * accumulated (in kilobits per second) when there is at least 22585d763aSVinicius Costa Gomes * one packet waiting for transmission. Packets are transmitted 23585d763aSVinicius Costa Gomes * when the current value of credits is equal or greater than 24585d763aSVinicius Costa Gomes * zero. When there is no packet to be transmitted the amount of 25585d763aSVinicius Costa Gomes * credits is set to zero. This is the main tunable of the CBS 26585d763aSVinicius Costa Gomes * algorithm. 27585d763aSVinicius Costa Gomes * 28585d763aSVinicius Costa Gomes * 'sendslope': 29585d763aSVinicius Costa Gomes * Sendslope is the rate of credits that is depleted (it should be a 30585d763aSVinicius Costa Gomes * negative number of kilobits per second) when a transmission is 31585d763aSVinicius Costa Gomes * ocurring. It can be calculated as follows, (IEEE 802.1Q-2014 Section 32585d763aSVinicius Costa Gomes * 8.6.8.2 item g): 33585d763aSVinicius Costa Gomes * 34585d763aSVinicius Costa Gomes * sendslope = idleslope - port_transmit_rate 35585d763aSVinicius Costa Gomes * 36585d763aSVinicius Costa Gomes * 'hicredit': Hicredit defines the maximum amount of credits (in 37585d763aSVinicius Costa Gomes * bytes) that can be accumulated. Hicredit depends on the 38585d763aSVinicius Costa Gomes * characteristics of interfering traffic, 39585d763aSVinicius Costa Gomes * 'max_interference_size' is the maximum size of any burst of 40585d763aSVinicius Costa Gomes * traffic that can delay the transmission of a frame that is 41585d763aSVinicius Costa Gomes * available for transmission for this traffic class, (IEEE 42585d763aSVinicius Costa Gomes * 802.1Q-2014 Annex L, Equation L-3): 43585d763aSVinicius Costa Gomes * 44585d763aSVinicius Costa Gomes * hicredit = max_interference_size * (idleslope / port_transmit_rate) 45585d763aSVinicius Costa Gomes * 46585d763aSVinicius Costa Gomes * 'locredit': Locredit is the minimum amount of credits that can 47585d763aSVinicius Costa Gomes * be reached. It is a function of the traffic flowing through 48585d763aSVinicius Costa Gomes * this qdisc (IEEE 802.1Q-2014 Annex L, Equation L-2): 49585d763aSVinicius Costa Gomes * 50585d763aSVinicius Costa Gomes * locredit = max_frame_size * (sendslope / port_transmit_rate) 51585d763aSVinicius Costa Gomes */ 52585d763aSVinicius Costa Gomes 53585d763aSVinicius Costa Gomes #include <linux/module.h> 54585d763aSVinicius Costa Gomes #include <linux/types.h> 55585d763aSVinicius Costa Gomes #include <linux/kernel.h> 56585d763aSVinicius Costa Gomes #include <linux/string.h> 57585d763aSVinicius Costa Gomes #include <linux/errno.h> 58585d763aSVinicius Costa Gomes #include <linux/skbuff.h> 59e0a7683dSLeandro Dorileo #include <net/netevent.h> 60585d763aSVinicius Costa Gomes #include <net/netlink.h> 61585d763aSVinicius Costa Gomes #include <net/sch_generic.h> 62585d763aSVinicius Costa Gomes #include <net/pkt_sched.h> 63585d763aSVinicius Costa Gomes 64e0a7683dSLeandro Dorileo static LIST_HEAD(cbs_list); 65e0a7683dSLeandro Dorileo static DEFINE_SPINLOCK(cbs_list_lock); 66e0a7683dSLeandro Dorileo 67585d763aSVinicius Costa Gomes #define BYTES_PER_KBIT (1000LL / 8) 68585d763aSVinicius Costa Gomes 69585d763aSVinicius Costa Gomes struct cbs_sched_data { 703d0bd028SVinicius Costa Gomes bool offload; 713d0bd028SVinicius Costa Gomes int queue; 72e0a7683dSLeandro Dorileo atomic64_t port_rate; /* in bytes/s */ 73585d763aSVinicius Costa Gomes s64 last; /* timestamp in ns */ 74585d763aSVinicius Costa Gomes s64 credits; /* in bytes */ 75585d763aSVinicius Costa Gomes s32 locredit; /* in bytes */ 76585d763aSVinicius Costa Gomes s32 hicredit; /* in bytes */ 77585d763aSVinicius Costa Gomes s64 sendslope; /* in bytes/s */ 78585d763aSVinicius Costa Gomes s64 idleslope; /* in bytes/s */ 79585d763aSVinicius Costa Gomes struct qdisc_watchdog watchdog; 80990e35ecSVinicius Costa Gomes int (*enqueue)(struct sk_buff *skb, struct Qdisc *sch, 81990e35ecSVinicius Costa Gomes struct sk_buff **to_free); 82585d763aSVinicius Costa Gomes struct sk_buff *(*dequeue)(struct Qdisc *sch); 83990e35ecSVinicius Costa Gomes struct Qdisc *qdisc; 84e0a7683dSLeandro Dorileo struct list_head cbs_list; 85585d763aSVinicius Costa Gomes }; 86585d763aSVinicius Costa Gomes 87990e35ecSVinicius Costa Gomes static int cbs_child_enqueue(struct sk_buff *skb, struct Qdisc *sch, 88990e35ecSVinicius Costa Gomes struct Qdisc *child, 89990e35ecSVinicius Costa Gomes struct sk_buff **to_free) 903d0bd028SVinicius Costa Gomes { 91f6bab199SToke Høiland-Jørgensen unsigned int len = qdisc_pkt_len(skb); 92990e35ecSVinicius Costa Gomes int err; 93990e35ecSVinicius Costa Gomes 94990e35ecSVinicius Costa Gomes err = child->ops->enqueue(skb, child, to_free); 95990e35ecSVinicius Costa Gomes if (err != NET_XMIT_SUCCESS) 96990e35ecSVinicius Costa Gomes return err; 97990e35ecSVinicius Costa Gomes 98f6bab199SToke Høiland-Jørgensen sch->qstats.backlog += len; 99990e35ecSVinicius Costa Gomes sch->q.qlen++; 100990e35ecSVinicius Costa Gomes 101990e35ecSVinicius Costa Gomes return NET_XMIT_SUCCESS; 1023d0bd028SVinicius Costa Gomes } 1033d0bd028SVinicius Costa Gomes 104990e35ecSVinicius Costa Gomes static int cbs_enqueue_offload(struct sk_buff *skb, struct Qdisc *sch, 105990e35ecSVinicius Costa Gomes struct sk_buff **to_free) 106585d763aSVinicius Costa Gomes { 107585d763aSVinicius Costa Gomes struct cbs_sched_data *q = qdisc_priv(sch); 108990e35ecSVinicius Costa Gomes struct Qdisc *qdisc = q->qdisc; 109990e35ecSVinicius Costa Gomes 110990e35ecSVinicius Costa Gomes return cbs_child_enqueue(skb, sch, qdisc, to_free); 111990e35ecSVinicius Costa Gomes } 112990e35ecSVinicius Costa Gomes 113990e35ecSVinicius Costa Gomes static int cbs_enqueue_soft(struct sk_buff *skb, struct Qdisc *sch, 114990e35ecSVinicius Costa Gomes struct sk_buff **to_free) 115990e35ecSVinicius Costa Gomes { 116990e35ecSVinicius Costa Gomes struct cbs_sched_data *q = qdisc_priv(sch); 117990e35ecSVinicius Costa Gomes struct Qdisc *qdisc = q->qdisc; 118585d763aSVinicius Costa Gomes 119585d763aSVinicius Costa Gomes if (sch->q.qlen == 0 && q->credits > 0) { 120585d763aSVinicius Costa Gomes /* We need to stop accumulating credits when there's 121585d763aSVinicius Costa Gomes * no enqueued packets and q->credits is positive. 122585d763aSVinicius Costa Gomes */ 123585d763aSVinicius Costa Gomes q->credits = 0; 124585d763aSVinicius Costa Gomes q->last = ktime_get_ns(); 125585d763aSVinicius Costa Gomes } 126585d763aSVinicius Costa Gomes 127990e35ecSVinicius Costa Gomes return cbs_child_enqueue(skb, sch, qdisc, to_free); 128585d763aSVinicius Costa Gomes } 129585d763aSVinicius Costa Gomes 130585d763aSVinicius Costa Gomes static int cbs_enqueue(struct sk_buff *skb, struct Qdisc *sch, 131585d763aSVinicius Costa Gomes struct sk_buff **to_free) 132585d763aSVinicius Costa Gomes { 133585d763aSVinicius Costa Gomes struct cbs_sched_data *q = qdisc_priv(sch); 134585d763aSVinicius Costa Gomes 135990e35ecSVinicius Costa Gomes return q->enqueue(skb, sch, to_free); 136585d763aSVinicius Costa Gomes } 137585d763aSVinicius Costa Gomes 138585d763aSVinicius Costa Gomes /* timediff is in ns, slope is in bytes/s */ 139585d763aSVinicius Costa Gomes static s64 timediff_to_credits(s64 timediff, s64 slope) 140585d763aSVinicius Costa Gomes { 141585d763aSVinicius Costa Gomes return div64_s64(timediff * slope, NSEC_PER_SEC); 142585d763aSVinicius Costa Gomes } 143585d763aSVinicius Costa Gomes 144585d763aSVinicius Costa Gomes static s64 delay_from_credits(s64 credits, s64 slope) 145585d763aSVinicius Costa Gomes { 146585d763aSVinicius Costa Gomes if (unlikely(slope == 0)) 147585d763aSVinicius Costa Gomes return S64_MAX; 148585d763aSVinicius Costa Gomes 149585d763aSVinicius Costa Gomes return div64_s64(-credits * NSEC_PER_SEC, slope); 150585d763aSVinicius Costa Gomes } 151585d763aSVinicius Costa Gomes 152585d763aSVinicius Costa Gomes static s64 credits_from_len(unsigned int len, s64 slope, s64 port_rate) 153585d763aSVinicius Costa Gomes { 154585d763aSVinicius Costa Gomes if (unlikely(port_rate == 0)) 155585d763aSVinicius Costa Gomes return S64_MAX; 156585d763aSVinicius Costa Gomes 157585d763aSVinicius Costa Gomes return div64_s64(len * slope, port_rate); 158585d763aSVinicius Costa Gomes } 159585d763aSVinicius Costa Gomes 160990e35ecSVinicius Costa Gomes static struct sk_buff *cbs_child_dequeue(struct Qdisc *sch, struct Qdisc *child) 161990e35ecSVinicius Costa Gomes { 162990e35ecSVinicius Costa Gomes struct sk_buff *skb; 163990e35ecSVinicius Costa Gomes 164990e35ecSVinicius Costa Gomes skb = child->ops->dequeue(child); 165990e35ecSVinicius Costa Gomes if (!skb) 166990e35ecSVinicius Costa Gomes return NULL; 167990e35ecSVinicius Costa Gomes 168990e35ecSVinicius Costa Gomes qdisc_qstats_backlog_dec(sch, skb); 169990e35ecSVinicius Costa Gomes qdisc_bstats_update(sch, skb); 170990e35ecSVinicius Costa Gomes sch->q.qlen--; 171990e35ecSVinicius Costa Gomes 172990e35ecSVinicius Costa Gomes return skb; 173990e35ecSVinicius Costa Gomes } 174990e35ecSVinicius Costa Gomes 175585d763aSVinicius Costa Gomes static struct sk_buff *cbs_dequeue_soft(struct Qdisc *sch) 176585d763aSVinicius Costa Gomes { 177585d763aSVinicius Costa Gomes struct cbs_sched_data *q = qdisc_priv(sch); 178990e35ecSVinicius Costa Gomes struct Qdisc *qdisc = q->qdisc; 179585d763aSVinicius Costa Gomes s64 now = ktime_get_ns(); 180585d763aSVinicius Costa Gomes struct sk_buff *skb; 181585d763aSVinicius Costa Gomes s64 credits; 182585d763aSVinicius Costa Gomes int len; 183585d763aSVinicius Costa Gomes 184585d763aSVinicius Costa Gomes if (q->credits < 0) { 185585d763aSVinicius Costa Gomes credits = timediff_to_credits(now - q->last, q->idleslope); 186585d763aSVinicius Costa Gomes 187585d763aSVinicius Costa Gomes credits = q->credits + credits; 188585d763aSVinicius Costa Gomes q->credits = min_t(s64, credits, q->hicredit); 189585d763aSVinicius Costa Gomes 190585d763aSVinicius Costa Gomes if (q->credits < 0) { 191585d763aSVinicius Costa Gomes s64 delay; 192585d763aSVinicius Costa Gomes 193585d763aSVinicius Costa Gomes delay = delay_from_credits(q->credits, q->idleslope); 194585d763aSVinicius Costa Gomes qdisc_watchdog_schedule_ns(&q->watchdog, now + delay); 195585d763aSVinicius Costa Gomes 196585d763aSVinicius Costa Gomes q->last = now; 197585d763aSVinicius Costa Gomes 198585d763aSVinicius Costa Gomes return NULL; 199585d763aSVinicius Costa Gomes } 200585d763aSVinicius Costa Gomes } 201990e35ecSVinicius Costa Gomes skb = cbs_child_dequeue(sch, qdisc); 202585d763aSVinicius Costa Gomes if (!skb) 203585d763aSVinicius Costa Gomes return NULL; 204585d763aSVinicius Costa Gomes 205585d763aSVinicius Costa Gomes len = qdisc_pkt_len(skb); 206585d763aSVinicius Costa Gomes 207585d763aSVinicius Costa Gomes /* As sendslope is a negative number, this will decrease the 208585d763aSVinicius Costa Gomes * amount of q->credits. 209585d763aSVinicius Costa Gomes */ 210e0a7683dSLeandro Dorileo credits = credits_from_len(len, q->sendslope, 211e0a7683dSLeandro Dorileo atomic64_read(&q->port_rate)); 212585d763aSVinicius Costa Gomes credits += q->credits; 213585d763aSVinicius Costa Gomes 214585d763aSVinicius Costa Gomes q->credits = max_t(s64, credits, q->locredit); 215585d763aSVinicius Costa Gomes q->last = now; 216585d763aSVinicius Costa Gomes 217585d763aSVinicius Costa Gomes return skb; 218585d763aSVinicius Costa Gomes } 219585d763aSVinicius Costa Gomes 2203d0bd028SVinicius Costa Gomes static struct sk_buff *cbs_dequeue_offload(struct Qdisc *sch) 2213d0bd028SVinicius Costa Gomes { 222990e35ecSVinicius Costa Gomes struct cbs_sched_data *q = qdisc_priv(sch); 223990e35ecSVinicius Costa Gomes struct Qdisc *qdisc = q->qdisc; 224990e35ecSVinicius Costa Gomes 225990e35ecSVinicius Costa Gomes return cbs_child_dequeue(sch, qdisc); 2263d0bd028SVinicius Costa Gomes } 2273d0bd028SVinicius Costa Gomes 228585d763aSVinicius Costa Gomes static struct sk_buff *cbs_dequeue(struct Qdisc *sch) 229585d763aSVinicius Costa Gomes { 230585d763aSVinicius Costa Gomes struct cbs_sched_data *q = qdisc_priv(sch); 231585d763aSVinicius Costa Gomes 232585d763aSVinicius Costa Gomes return q->dequeue(sch); 233585d763aSVinicius Costa Gomes } 234585d763aSVinicius Costa Gomes 235585d763aSVinicius Costa Gomes static const struct nla_policy cbs_policy[TCA_CBS_MAX + 1] = { 236585d763aSVinicius Costa Gomes [TCA_CBS_PARMS] = { .len = sizeof(struct tc_cbs_qopt) }, 237585d763aSVinicius Costa Gomes }; 238585d763aSVinicius Costa Gomes 2393d0bd028SVinicius Costa Gomes static void cbs_disable_offload(struct net_device *dev, 2403d0bd028SVinicius Costa Gomes struct cbs_sched_data *q) 2413d0bd028SVinicius Costa Gomes { 2423d0bd028SVinicius Costa Gomes struct tc_cbs_qopt_offload cbs = { }; 2433d0bd028SVinicius Costa Gomes const struct net_device_ops *ops; 2443d0bd028SVinicius Costa Gomes int err; 2453d0bd028SVinicius Costa Gomes 2463d0bd028SVinicius Costa Gomes if (!q->offload) 2473d0bd028SVinicius Costa Gomes return; 2483d0bd028SVinicius Costa Gomes 2493d0bd028SVinicius Costa Gomes q->enqueue = cbs_enqueue_soft; 2503d0bd028SVinicius Costa Gomes q->dequeue = cbs_dequeue_soft; 2513d0bd028SVinicius Costa Gomes 2523d0bd028SVinicius Costa Gomes ops = dev->netdev_ops; 2533d0bd028SVinicius Costa Gomes if (!ops->ndo_setup_tc) 2543d0bd028SVinicius Costa Gomes return; 2553d0bd028SVinicius Costa Gomes 2563d0bd028SVinicius Costa Gomes cbs.queue = q->queue; 2573d0bd028SVinicius Costa Gomes cbs.enable = 0; 2583d0bd028SVinicius Costa Gomes 2598521db4cSNogah Frankel err = ops->ndo_setup_tc(dev, TC_SETUP_QDISC_CBS, &cbs); 2603d0bd028SVinicius Costa Gomes if (err < 0) 2613d0bd028SVinicius Costa Gomes pr_warn("Couldn't disable CBS offload for queue %d\n", 2623d0bd028SVinicius Costa Gomes cbs.queue); 2633d0bd028SVinicius Costa Gomes } 2643d0bd028SVinicius Costa Gomes 2653d0bd028SVinicius Costa Gomes static int cbs_enable_offload(struct net_device *dev, struct cbs_sched_data *q, 266710fb396SAlexander Aring const struct tc_cbs_qopt *opt, 267710fb396SAlexander Aring struct netlink_ext_ack *extack) 2683d0bd028SVinicius Costa Gomes { 2693d0bd028SVinicius Costa Gomes const struct net_device_ops *ops = dev->netdev_ops; 2703d0bd028SVinicius Costa Gomes struct tc_cbs_qopt_offload cbs = { }; 2713d0bd028SVinicius Costa Gomes int err; 2723d0bd028SVinicius Costa Gomes 273710fb396SAlexander Aring if (!ops->ndo_setup_tc) { 274710fb396SAlexander Aring NL_SET_ERR_MSG(extack, "Specified device does not support cbs offload"); 2753d0bd028SVinicius Costa Gomes return -EOPNOTSUPP; 276710fb396SAlexander Aring } 2773d0bd028SVinicius Costa Gomes 2783d0bd028SVinicius Costa Gomes cbs.queue = q->queue; 2793d0bd028SVinicius Costa Gomes 2803d0bd028SVinicius Costa Gomes cbs.enable = 1; 2813d0bd028SVinicius Costa Gomes cbs.hicredit = opt->hicredit; 2823d0bd028SVinicius Costa Gomes cbs.locredit = opt->locredit; 2833d0bd028SVinicius Costa Gomes cbs.idleslope = opt->idleslope; 2843d0bd028SVinicius Costa Gomes cbs.sendslope = opt->sendslope; 2853d0bd028SVinicius Costa Gomes 2868521db4cSNogah Frankel err = ops->ndo_setup_tc(dev, TC_SETUP_QDISC_CBS, &cbs); 287710fb396SAlexander Aring if (err < 0) { 288710fb396SAlexander Aring NL_SET_ERR_MSG(extack, "Specified device failed to setup cbs hardware offload"); 2893d0bd028SVinicius Costa Gomes return err; 290710fb396SAlexander Aring } 2913d0bd028SVinicius Costa Gomes 2923d0bd028SVinicius Costa Gomes q->enqueue = cbs_enqueue_offload; 2933d0bd028SVinicius Costa Gomes q->dequeue = cbs_dequeue_offload; 2943d0bd028SVinicius Costa Gomes 2953d0bd028SVinicius Costa Gomes return 0; 2963d0bd028SVinicius Costa Gomes } 2973d0bd028SVinicius Costa Gomes 298e0a7683dSLeandro Dorileo static void cbs_set_port_rate(struct net_device *dev, struct cbs_sched_data *q) 299e0a7683dSLeandro Dorileo { 300e0a7683dSLeandro Dorileo struct ethtool_link_ksettings ecmd; 3011c6c09a0SVladimir Oltean int speed = SPEED_10; 302e0a7683dSLeandro Dorileo int port_rate = -1; 3031c6c09a0SVladimir Oltean int err; 304e0a7683dSLeandro Dorileo 3051c6c09a0SVladimir Oltean err = __ethtool_get_link_ksettings(dev, &ecmd); 3061c6c09a0SVladimir Oltean if (err < 0) 3071c6c09a0SVladimir Oltean goto skip; 3081c6c09a0SVladimir Oltean 3091c6c09a0SVladimir Oltean if (ecmd.base.speed != SPEED_UNKNOWN) 3101c6c09a0SVladimir Oltean speed = ecmd.base.speed; 3111c6c09a0SVladimir Oltean 3121c6c09a0SVladimir Oltean skip: 3131c6c09a0SVladimir Oltean port_rate = speed * 1000 * BYTES_PER_KBIT; 314e0a7683dSLeandro Dorileo 315e0a7683dSLeandro Dorileo atomic64_set(&q->port_rate, port_rate); 316e0a7683dSLeandro Dorileo netdev_dbg(dev, "cbs: set %s's port_rate to: %lld, linkspeed: %d\n", 317e0a7683dSLeandro Dorileo dev->name, (long long)atomic64_read(&q->port_rate), 318e0a7683dSLeandro Dorileo ecmd.base.speed); 319e0a7683dSLeandro Dorileo } 320e0a7683dSLeandro Dorileo 321e0a7683dSLeandro Dorileo static int cbs_dev_notifier(struct notifier_block *nb, unsigned long event, 322e0a7683dSLeandro Dorileo void *ptr) 323e0a7683dSLeandro Dorileo { 324e0a7683dSLeandro Dorileo struct net_device *dev = netdev_notifier_info_to_dev(ptr); 325e0a7683dSLeandro Dorileo struct cbs_sched_data *q; 326e0a7683dSLeandro Dorileo struct net_device *qdev; 327e0a7683dSLeandro Dorileo bool found = false; 328e0a7683dSLeandro Dorileo 329e0a7683dSLeandro Dorileo ASSERT_RTNL(); 330e0a7683dSLeandro Dorileo 331e0a7683dSLeandro Dorileo if (event != NETDEV_UP && event != NETDEV_CHANGE) 332e0a7683dSLeandro Dorileo return NOTIFY_DONE; 333e0a7683dSLeandro Dorileo 334e0a7683dSLeandro Dorileo spin_lock(&cbs_list_lock); 335e0a7683dSLeandro Dorileo list_for_each_entry(q, &cbs_list, cbs_list) { 336e0a7683dSLeandro Dorileo qdev = qdisc_dev(q->qdisc); 337e0a7683dSLeandro Dorileo if (qdev == dev) { 338e0a7683dSLeandro Dorileo found = true; 339e0a7683dSLeandro Dorileo break; 340e0a7683dSLeandro Dorileo } 341e0a7683dSLeandro Dorileo } 342e0a7683dSLeandro Dorileo spin_unlock(&cbs_list_lock); 343e0a7683dSLeandro Dorileo 344e0a7683dSLeandro Dorileo if (found) 345e0a7683dSLeandro Dorileo cbs_set_port_rate(dev, q); 346e0a7683dSLeandro Dorileo 347e0a7683dSLeandro Dorileo return NOTIFY_DONE; 348e0a7683dSLeandro Dorileo } 349e0a7683dSLeandro Dorileo 3502030721cSAlexander Aring static int cbs_change(struct Qdisc *sch, struct nlattr *opt, 3512030721cSAlexander Aring struct netlink_ext_ack *extack) 352585d763aSVinicius Costa Gomes { 353585d763aSVinicius Costa Gomes struct cbs_sched_data *q = qdisc_priv(sch); 354585d763aSVinicius Costa Gomes struct net_device *dev = qdisc_dev(sch); 355585d763aSVinicius Costa Gomes struct nlattr *tb[TCA_CBS_MAX + 1]; 356585d763aSVinicius Costa Gomes struct tc_cbs_qopt *qopt; 357585d763aSVinicius Costa Gomes int err; 358585d763aSVinicius Costa Gomes 3598cb08174SJohannes Berg err = nla_parse_nested_deprecated(tb, TCA_CBS_MAX, opt, cbs_policy, 3608cb08174SJohannes Berg extack); 361585d763aSVinicius Costa Gomes if (err < 0) 362585d763aSVinicius Costa Gomes return err; 363585d763aSVinicius Costa Gomes 364710fb396SAlexander Aring if (!tb[TCA_CBS_PARMS]) { 365710fb396SAlexander Aring NL_SET_ERR_MSG(extack, "Missing CBS parameter which are mandatory"); 366585d763aSVinicius Costa Gomes return -EINVAL; 367710fb396SAlexander Aring } 368585d763aSVinicius Costa Gomes 369585d763aSVinicius Costa Gomes qopt = nla_data(tb[TCA_CBS_PARMS]); 370585d763aSVinicius Costa Gomes 3713d0bd028SVinicius Costa Gomes if (!qopt->offload) { 372e0a7683dSLeandro Dorileo cbs_set_port_rate(dev, q); 3733d0bd028SVinicius Costa Gomes cbs_disable_offload(dev, q); 3743d0bd028SVinicius Costa Gomes } else { 375710fb396SAlexander Aring err = cbs_enable_offload(dev, q, qopt, extack); 3763d0bd028SVinicius Costa Gomes if (err < 0) 3773d0bd028SVinicius Costa Gomes return err; 3783d0bd028SVinicius Costa Gomes } 379585d763aSVinicius Costa Gomes 3803d0bd028SVinicius Costa Gomes /* Everything went OK, save the parameters used. */ 381585d763aSVinicius Costa Gomes q->hicredit = qopt->hicredit; 382585d763aSVinicius Costa Gomes q->locredit = qopt->locredit; 383585d763aSVinicius Costa Gomes q->idleslope = qopt->idleslope * BYTES_PER_KBIT; 384585d763aSVinicius Costa Gomes q->sendslope = qopt->sendslope * BYTES_PER_KBIT; 3853d0bd028SVinicius Costa Gomes q->offload = qopt->offload; 386585d763aSVinicius Costa Gomes 387585d763aSVinicius Costa Gomes return 0; 388585d763aSVinicius Costa Gomes } 389585d763aSVinicius Costa Gomes 390e63d7dfdSAlexander Aring static int cbs_init(struct Qdisc *sch, struct nlattr *opt, 391e63d7dfdSAlexander Aring struct netlink_ext_ack *extack) 392585d763aSVinicius Costa Gomes { 393585d763aSVinicius Costa Gomes struct cbs_sched_data *q = qdisc_priv(sch); 3943d0bd028SVinicius Costa Gomes struct net_device *dev = qdisc_dev(sch); 395e0a7683dSLeandro Dorileo int err; 396585d763aSVinicius Costa Gomes 397710fb396SAlexander Aring if (!opt) { 398710fb396SAlexander Aring NL_SET_ERR_MSG(extack, "Missing CBS qdisc options which are mandatory"); 399585d763aSVinicius Costa Gomes return -EINVAL; 400710fb396SAlexander Aring } 401585d763aSVinicius Costa Gomes 402990e35ecSVinicius Costa Gomes q->qdisc = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, 403990e35ecSVinicius Costa Gomes sch->handle, extack); 404990e35ecSVinicius Costa Gomes if (!q->qdisc) 405990e35ecSVinicius Costa Gomes return -ENOMEM; 406990e35ecSVinicius Costa Gomes 407990e35ecSVinicius Costa Gomes qdisc_hash_add(q->qdisc, false); 408990e35ecSVinicius Costa Gomes 4093d0bd028SVinicius Costa Gomes q->queue = sch->dev_queue - netdev_get_tx_queue(dev, 0); 4103d0bd028SVinicius Costa Gomes 4113d0bd028SVinicius Costa Gomes q->enqueue = cbs_enqueue_soft; 4123d0bd028SVinicius Costa Gomes q->dequeue = cbs_dequeue_soft; 4133d0bd028SVinicius Costa Gomes 414585d763aSVinicius Costa Gomes qdisc_watchdog_init(&q->watchdog, sch); 415585d763aSVinicius Costa Gomes 416e0a7683dSLeandro Dorileo err = cbs_change(sch, opt, extack); 417e0a7683dSLeandro Dorileo if (err) 418e0a7683dSLeandro Dorileo return err; 419e0a7683dSLeandro Dorileo 420e0a7683dSLeandro Dorileo if (!q->offload) { 421e0a7683dSLeandro Dorileo spin_lock(&cbs_list_lock); 422e0a7683dSLeandro Dorileo list_add(&q->cbs_list, &cbs_list); 423e0a7683dSLeandro Dorileo spin_unlock(&cbs_list_lock); 424e0a7683dSLeandro Dorileo } 425e0a7683dSLeandro Dorileo 426e0a7683dSLeandro Dorileo return 0; 427585d763aSVinicius Costa Gomes } 428585d763aSVinicius Costa Gomes 429585d763aSVinicius Costa Gomes static void cbs_destroy(struct Qdisc *sch) 430585d763aSVinicius Costa Gomes { 431585d763aSVinicius Costa Gomes struct cbs_sched_data *q = qdisc_priv(sch); 4323d0bd028SVinicius Costa Gomes struct net_device *dev = qdisc_dev(sch); 433585d763aSVinicius Costa Gomes 434e0a7683dSLeandro Dorileo spin_lock(&cbs_list_lock); 435e0a7683dSLeandro Dorileo list_del(&q->cbs_list); 436e0a7683dSLeandro Dorileo spin_unlock(&cbs_list_lock); 4373d0bd028SVinicius Costa Gomes 438e0a7683dSLeandro Dorileo qdisc_watchdog_cancel(&q->watchdog); 4393d0bd028SVinicius Costa Gomes cbs_disable_offload(dev, q); 440990e35ecSVinicius Costa Gomes 441990e35ecSVinicius Costa Gomes if (q->qdisc) 44286bd446bSVlad Buslov qdisc_put(q->qdisc); 443585d763aSVinicius Costa Gomes } 444585d763aSVinicius Costa Gomes 445585d763aSVinicius Costa Gomes static int cbs_dump(struct Qdisc *sch, struct sk_buff *skb) 446585d763aSVinicius Costa Gomes { 447585d763aSVinicius Costa Gomes struct cbs_sched_data *q = qdisc_priv(sch); 448585d763aSVinicius Costa Gomes struct tc_cbs_qopt opt = { }; 449585d763aSVinicius Costa Gomes struct nlattr *nest; 450585d763aSVinicius Costa Gomes 451ae0be8deSMichal Kubecek nest = nla_nest_start_noflag(skb, TCA_OPTIONS); 452585d763aSVinicius Costa Gomes if (!nest) 453585d763aSVinicius Costa Gomes goto nla_put_failure; 454585d763aSVinicius Costa Gomes 455585d763aSVinicius Costa Gomes opt.hicredit = q->hicredit; 456585d763aSVinicius Costa Gomes opt.locredit = q->locredit; 457585d763aSVinicius Costa Gomes opt.sendslope = div64_s64(q->sendslope, BYTES_PER_KBIT); 458585d763aSVinicius Costa Gomes opt.idleslope = div64_s64(q->idleslope, BYTES_PER_KBIT); 4593d0bd028SVinicius Costa Gomes opt.offload = q->offload; 460585d763aSVinicius Costa Gomes 461585d763aSVinicius Costa Gomes if (nla_put(skb, TCA_CBS_PARMS, sizeof(opt), &opt)) 462585d763aSVinicius Costa Gomes goto nla_put_failure; 463585d763aSVinicius Costa Gomes 464585d763aSVinicius Costa Gomes return nla_nest_end(skb, nest); 465585d763aSVinicius Costa Gomes 466585d763aSVinicius Costa Gomes nla_put_failure: 467585d763aSVinicius Costa Gomes nla_nest_cancel(skb, nest); 468585d763aSVinicius Costa Gomes return -1; 469585d763aSVinicius Costa Gomes } 470585d763aSVinicius Costa Gomes 471990e35ecSVinicius Costa Gomes static int cbs_dump_class(struct Qdisc *sch, unsigned long cl, 472990e35ecSVinicius Costa Gomes struct sk_buff *skb, struct tcmsg *tcm) 473990e35ecSVinicius Costa Gomes { 474990e35ecSVinicius Costa Gomes struct cbs_sched_data *q = qdisc_priv(sch); 475990e35ecSVinicius Costa Gomes 476990e35ecSVinicius Costa Gomes if (cl != 1 || !q->qdisc) /* only one class */ 477990e35ecSVinicius Costa Gomes return -ENOENT; 478990e35ecSVinicius Costa Gomes 479990e35ecSVinicius Costa Gomes tcm->tcm_handle |= TC_H_MIN(1); 480990e35ecSVinicius Costa Gomes tcm->tcm_info = q->qdisc->handle; 481990e35ecSVinicius Costa Gomes 482990e35ecSVinicius Costa Gomes return 0; 483990e35ecSVinicius Costa Gomes } 484990e35ecSVinicius Costa Gomes 485990e35ecSVinicius Costa Gomes static int cbs_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new, 486990e35ecSVinicius Costa Gomes struct Qdisc **old, struct netlink_ext_ack *extack) 487990e35ecSVinicius Costa Gomes { 488990e35ecSVinicius Costa Gomes struct cbs_sched_data *q = qdisc_priv(sch); 489990e35ecSVinicius Costa Gomes 490990e35ecSVinicius Costa Gomes if (!new) { 491990e35ecSVinicius Costa Gomes new = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, 492990e35ecSVinicius Costa Gomes sch->handle, NULL); 493990e35ecSVinicius Costa Gomes if (!new) 494990e35ecSVinicius Costa Gomes new = &noop_qdisc; 495990e35ecSVinicius Costa Gomes } 496990e35ecSVinicius Costa Gomes 497990e35ecSVinicius Costa Gomes *old = qdisc_replace(sch, new, &q->qdisc); 498990e35ecSVinicius Costa Gomes return 0; 499990e35ecSVinicius Costa Gomes } 500990e35ecSVinicius Costa Gomes 501990e35ecSVinicius Costa Gomes static struct Qdisc *cbs_leaf(struct Qdisc *sch, unsigned long arg) 502990e35ecSVinicius Costa Gomes { 503990e35ecSVinicius Costa Gomes struct cbs_sched_data *q = qdisc_priv(sch); 504990e35ecSVinicius Costa Gomes 505990e35ecSVinicius Costa Gomes return q->qdisc; 506990e35ecSVinicius Costa Gomes } 507990e35ecSVinicius Costa Gomes 508990e35ecSVinicius Costa Gomes static unsigned long cbs_find(struct Qdisc *sch, u32 classid) 509990e35ecSVinicius Costa Gomes { 510990e35ecSVinicius Costa Gomes return 1; 511990e35ecSVinicius Costa Gomes } 512990e35ecSVinicius Costa Gomes 513990e35ecSVinicius Costa Gomes static void cbs_walk(struct Qdisc *sch, struct qdisc_walker *walker) 514990e35ecSVinicius Costa Gomes { 515990e35ecSVinicius Costa Gomes if (!walker->stop) { 516990e35ecSVinicius Costa Gomes if (walker->count >= walker->skip) { 517990e35ecSVinicius Costa Gomes if (walker->fn(sch, 1, walker) < 0) { 518990e35ecSVinicius Costa Gomes walker->stop = 1; 519990e35ecSVinicius Costa Gomes return; 520990e35ecSVinicius Costa Gomes } 521990e35ecSVinicius Costa Gomes } 522990e35ecSVinicius Costa Gomes walker->count++; 523990e35ecSVinicius Costa Gomes } 524990e35ecSVinicius Costa Gomes } 525990e35ecSVinicius Costa Gomes 526990e35ecSVinicius Costa Gomes static const struct Qdisc_class_ops cbs_class_ops = { 527990e35ecSVinicius Costa Gomes .graft = cbs_graft, 528990e35ecSVinicius Costa Gomes .leaf = cbs_leaf, 529990e35ecSVinicius Costa Gomes .find = cbs_find, 530990e35ecSVinicius Costa Gomes .walk = cbs_walk, 531990e35ecSVinicius Costa Gomes .dump = cbs_dump_class, 532990e35ecSVinicius Costa Gomes }; 533990e35ecSVinicius Costa Gomes 534585d763aSVinicius Costa Gomes static struct Qdisc_ops cbs_qdisc_ops __read_mostly = { 535585d763aSVinicius Costa Gomes .id = "cbs", 536990e35ecSVinicius Costa Gomes .cl_ops = &cbs_class_ops, 537585d763aSVinicius Costa Gomes .priv_size = sizeof(struct cbs_sched_data), 538585d763aSVinicius Costa Gomes .enqueue = cbs_enqueue, 539585d763aSVinicius Costa Gomes .dequeue = cbs_dequeue, 540585d763aSVinicius Costa Gomes .peek = qdisc_peek_dequeued, 541585d763aSVinicius Costa Gomes .init = cbs_init, 542585d763aSVinicius Costa Gomes .reset = qdisc_reset_queue, 543585d763aSVinicius Costa Gomes .destroy = cbs_destroy, 544585d763aSVinicius Costa Gomes .change = cbs_change, 545585d763aSVinicius Costa Gomes .dump = cbs_dump, 546585d763aSVinicius Costa Gomes .owner = THIS_MODULE, 547585d763aSVinicius Costa Gomes }; 548585d763aSVinicius Costa Gomes 549e0a7683dSLeandro Dorileo static struct notifier_block cbs_device_notifier = { 550e0a7683dSLeandro Dorileo .notifier_call = cbs_dev_notifier, 551e0a7683dSLeandro Dorileo }; 552e0a7683dSLeandro Dorileo 553585d763aSVinicius Costa Gomes static int __init cbs_module_init(void) 554585d763aSVinicius Costa Gomes { 55545d5cb13SYueHaibing int err; 556e0a7683dSLeandro Dorileo 55745d5cb13SYueHaibing err = register_netdevice_notifier(&cbs_device_notifier); 558e0a7683dSLeandro Dorileo if (err) 559e0a7683dSLeandro Dorileo return err; 560e0a7683dSLeandro Dorileo 56145d5cb13SYueHaibing err = register_qdisc(&cbs_qdisc_ops); 56245d5cb13SYueHaibing if (err) 56345d5cb13SYueHaibing unregister_netdevice_notifier(&cbs_device_notifier); 56445d5cb13SYueHaibing 56545d5cb13SYueHaibing return err; 566585d763aSVinicius Costa Gomes } 567585d763aSVinicius Costa Gomes 568585d763aSVinicius Costa Gomes static void __exit cbs_module_exit(void) 569585d763aSVinicius Costa Gomes { 570585d763aSVinicius Costa Gomes unregister_qdisc(&cbs_qdisc_ops); 571e0a7683dSLeandro Dorileo unregister_netdevice_notifier(&cbs_device_notifier); 572585d763aSVinicius Costa Gomes } 573585d763aSVinicius Costa Gomes module_init(cbs_module_init) 574585d763aSVinicius Costa Gomes module_exit(cbs_module_exit) 575585d763aSVinicius Costa Gomes MODULE_LICENSE("GPL"); 576