Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / net / sched / sch_mqprio.c
diff --git a/kernel/net/sched/sch_mqprio.c b/kernel/net/sched/sch_mqprio.c
new file mode 100644 (file)
index 0000000..3811a74
--- /dev/null
@@ -0,0 +1,428 @@
+/*
+ * net/sched/sch_mqprio.c
+ *
+ * Copyright (c) 2010 John Fastabend <john.r.fastabend@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ */
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/skbuff.h>
+#include <linux/module.h>
+#include <net/netlink.h>
+#include <net/pkt_sched.h>
+#include <net/sch_generic.h>
+
+struct mqprio_sched {
+       struct Qdisc            **qdiscs;
+       int hw_owned;
+};
+
+static void mqprio_destroy(struct Qdisc *sch)
+{
+       struct net_device *dev = qdisc_dev(sch);
+       struct mqprio_sched *priv = qdisc_priv(sch);
+       unsigned int ntx;
+
+       if (priv->qdiscs) {
+               for (ntx = 0;
+                    ntx < dev->num_tx_queues && priv->qdiscs[ntx];
+                    ntx++)
+                       qdisc_destroy(priv->qdiscs[ntx]);
+               kfree(priv->qdiscs);
+       }
+
+       if (priv->hw_owned && dev->netdev_ops->ndo_setup_tc)
+               dev->netdev_ops->ndo_setup_tc(dev, 0);
+       else
+               netdev_set_num_tc(dev, 0);
+}
+
+static int mqprio_parse_opt(struct net_device *dev, struct tc_mqprio_qopt *qopt)
+{
+       int i, j;
+
+       /* Verify num_tc is not out of max range */
+       if (qopt->num_tc > TC_MAX_QUEUE)
+               return -EINVAL;
+
+       /* Verify priority mapping uses valid tcs */
+       for (i = 0; i < TC_BITMASK + 1; i++) {
+               if (qopt->prio_tc_map[i] >= qopt->num_tc)
+                       return -EINVAL;
+       }
+
+       /* net_device does not support requested operation */
+       if (qopt->hw && !dev->netdev_ops->ndo_setup_tc)
+               return -EINVAL;
+
+       /* if hw owned qcount and qoffset are taken from LLD so
+        * no reason to verify them here
+        */
+       if (qopt->hw)
+               return 0;
+
+       for (i = 0; i < qopt->num_tc; i++) {
+               unsigned int last = qopt->offset[i] + qopt->count[i];
+
+               /* Verify the queue count is in tx range being equal to the
+                * real_num_tx_queues indicates the last queue is in use.
+                */
+               if (qopt->offset[i] >= dev->real_num_tx_queues ||
+                   !qopt->count[i] ||
+                   last > dev->real_num_tx_queues)
+                       return -EINVAL;
+
+               /* Verify that the offset and counts do not overlap */
+               for (j = i + 1; j < qopt->num_tc; j++) {
+                       if (last > qopt->offset[j])
+                               return -EINVAL;
+               }
+       }
+
+       return 0;
+}
+
+static int mqprio_init(struct Qdisc *sch, struct nlattr *opt)
+{
+       struct net_device *dev = qdisc_dev(sch);
+       struct mqprio_sched *priv = qdisc_priv(sch);
+       struct netdev_queue *dev_queue;
+       struct Qdisc *qdisc;
+       int i, err = -EOPNOTSUPP;
+       struct tc_mqprio_qopt *qopt = NULL;
+
+       BUILD_BUG_ON(TC_MAX_QUEUE != TC_QOPT_MAX_QUEUE);
+       BUILD_BUG_ON(TC_BITMASK != TC_QOPT_BITMASK);
+
+       if (sch->parent != TC_H_ROOT)
+               return -EOPNOTSUPP;
+
+       if (!netif_is_multiqueue(dev))
+               return -EOPNOTSUPP;
+
+       if (!opt || nla_len(opt) < sizeof(*qopt))
+               return -EINVAL;
+
+       qopt = nla_data(opt);
+       if (mqprio_parse_opt(dev, qopt))
+               return -EINVAL;
+
+       /* pre-allocate qdisc, attachment can't fail */
+       priv->qdiscs = kcalloc(dev->num_tx_queues, sizeof(priv->qdiscs[0]),
+                              GFP_KERNEL);
+       if (priv->qdiscs == NULL) {
+               err = -ENOMEM;
+               goto err;
+       }
+
+       for (i = 0; i < dev->num_tx_queues; i++) {
+               dev_queue = netdev_get_tx_queue(dev, i);
+               qdisc = qdisc_create_dflt(dev_queue, default_qdisc_ops,
+                                         TC_H_MAKE(TC_H_MAJ(sch->handle),
+                                                   TC_H_MIN(i + 1)));
+               if (qdisc == NULL) {
+                       err = -ENOMEM;
+                       goto err;
+               }
+               priv->qdiscs[i] = qdisc;
+               qdisc->flags |= TCQ_F_ONETXQUEUE;
+       }
+
+       /* If the mqprio options indicate that hardware should own
+        * the queue mapping then run ndo_setup_tc otherwise use the
+        * supplied and verified mapping
+        */
+       if (qopt->hw) {
+               priv->hw_owned = 1;
+               err = dev->netdev_ops->ndo_setup_tc(dev, qopt->num_tc);
+               if (err)
+                       goto err;
+       } else {
+               netdev_set_num_tc(dev, qopt->num_tc);
+               for (i = 0; i < qopt->num_tc; i++)
+                       netdev_set_tc_queue(dev, i,
+                                           qopt->count[i], qopt->offset[i]);
+       }
+
+       /* Always use supplied priority mappings */
+       for (i = 0; i < TC_BITMASK + 1; i++)
+               netdev_set_prio_tc_map(dev, i, qopt->prio_tc_map[i]);
+
+       sch->flags |= TCQ_F_MQROOT;
+       return 0;
+
+err:
+       mqprio_destroy(sch);
+       return err;
+}
+
+static void mqprio_attach(struct Qdisc *sch)
+{
+       struct net_device *dev = qdisc_dev(sch);
+       struct mqprio_sched *priv = qdisc_priv(sch);
+       struct Qdisc *qdisc, *old;
+       unsigned int ntx;
+
+       /* Attach underlying qdisc */
+       for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
+               qdisc = priv->qdiscs[ntx];
+               old = dev_graft_qdisc(qdisc->dev_queue, qdisc);
+               if (old)
+                       qdisc_destroy(old);
+               if (ntx < dev->real_num_tx_queues)
+                       qdisc_list_add(qdisc);
+       }
+       kfree(priv->qdiscs);
+       priv->qdiscs = NULL;
+}
+
+static struct netdev_queue *mqprio_queue_get(struct Qdisc *sch,
+                                            unsigned long cl)
+{
+       struct net_device *dev = qdisc_dev(sch);
+       unsigned long ntx = cl - 1 - netdev_get_num_tc(dev);
+
+       if (ntx >= dev->num_tx_queues)
+               return NULL;
+       return netdev_get_tx_queue(dev, ntx);
+}
+
+static int mqprio_graft(struct Qdisc *sch, unsigned long cl, struct Qdisc *new,
+                   struct Qdisc **old)
+{
+       struct net_device *dev = qdisc_dev(sch);
+       struct netdev_queue *dev_queue = mqprio_queue_get(sch, cl);
+
+       if (!dev_queue)
+               return -EINVAL;
+
+       if (dev->flags & IFF_UP)
+               dev_deactivate(dev);
+
+       *old = dev_graft_qdisc(dev_queue, new);
+
+       if (new)
+               new->flags |= TCQ_F_ONETXQUEUE;
+
+       if (dev->flags & IFF_UP)
+               dev_activate(dev);
+
+       return 0;
+}
+
+static int mqprio_dump(struct Qdisc *sch, struct sk_buff *skb)
+{
+       struct net_device *dev = qdisc_dev(sch);
+       struct mqprio_sched *priv = qdisc_priv(sch);
+       unsigned char *b = skb_tail_pointer(skb);
+       struct tc_mqprio_qopt opt = { 0 };
+       struct Qdisc *qdisc;
+       unsigned int i;
+
+       sch->q.qlen = 0;
+       memset(&sch->bstats, 0, sizeof(sch->bstats));
+       memset(&sch->qstats, 0, sizeof(sch->qstats));
+
+       for (i = 0; i < dev->num_tx_queues; i++) {
+               qdisc = rtnl_dereference(netdev_get_tx_queue(dev, i)->qdisc);
+               spin_lock_bh(qdisc_lock(qdisc));
+               sch->q.qlen             += qdisc->q.qlen;
+               sch->bstats.bytes       += qdisc->bstats.bytes;
+               sch->bstats.packets     += qdisc->bstats.packets;
+               sch->qstats.backlog     += qdisc->qstats.backlog;
+               sch->qstats.drops       += qdisc->qstats.drops;
+               sch->qstats.requeues    += qdisc->qstats.requeues;
+               sch->qstats.overlimits  += qdisc->qstats.overlimits;
+               spin_unlock_bh(qdisc_lock(qdisc));
+       }
+
+       opt.num_tc = netdev_get_num_tc(dev);
+       memcpy(opt.prio_tc_map, dev->prio_tc_map, sizeof(opt.prio_tc_map));
+       opt.hw = priv->hw_owned;
+
+       for (i = 0; i < netdev_get_num_tc(dev); i++) {
+               opt.count[i] = dev->tc_to_txq[i].count;
+               opt.offset[i] = dev->tc_to_txq[i].offset;
+       }
+
+       if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt))
+               goto nla_put_failure;
+
+       return skb->len;
+nla_put_failure:
+       nlmsg_trim(skb, b);
+       return -1;
+}
+
+static struct Qdisc *mqprio_leaf(struct Qdisc *sch, unsigned long cl)
+{
+       struct netdev_queue *dev_queue = mqprio_queue_get(sch, cl);
+
+       if (!dev_queue)
+               return NULL;
+
+       return dev_queue->qdisc_sleeping;
+}
+
+static unsigned long mqprio_get(struct Qdisc *sch, u32 classid)
+{
+       struct net_device *dev = qdisc_dev(sch);
+       unsigned int ntx = TC_H_MIN(classid);
+
+       if (ntx > dev->num_tx_queues + netdev_get_num_tc(dev))
+               return 0;
+       return ntx;
+}
+
+static void mqprio_put(struct Qdisc *sch, unsigned long cl)
+{
+}
+
+static int mqprio_dump_class(struct Qdisc *sch, unsigned long cl,
+                        struct sk_buff *skb, struct tcmsg *tcm)
+{
+       struct net_device *dev = qdisc_dev(sch);
+
+       if (cl <= netdev_get_num_tc(dev)) {
+               tcm->tcm_parent = TC_H_ROOT;
+               tcm->tcm_info = 0;
+       } else {
+               int i;
+               struct netdev_queue *dev_queue;
+
+               dev_queue = mqprio_queue_get(sch, cl);
+               tcm->tcm_parent = 0;
+               for (i = 0; i < netdev_get_num_tc(dev); i++) {
+                       struct netdev_tc_txq tc = dev->tc_to_txq[i];
+                       int q_idx = cl - netdev_get_num_tc(dev);
+
+                       if (q_idx > tc.offset &&
+                           q_idx <= tc.offset + tc.count) {
+                               tcm->tcm_parent =
+                                       TC_H_MAKE(TC_H_MAJ(sch->handle),
+                                                 TC_H_MIN(i + 1));
+                               break;
+                       }
+               }
+               tcm->tcm_info = dev_queue->qdisc_sleeping->handle;
+       }
+       tcm->tcm_handle |= TC_H_MIN(cl);
+       return 0;
+}
+
+static int mqprio_dump_class_stats(struct Qdisc *sch, unsigned long cl,
+                                  struct gnet_dump *d)
+       __releases(d->lock)
+       __acquires(d->lock)
+{
+       struct net_device *dev = qdisc_dev(sch);
+
+       if (cl <= netdev_get_num_tc(dev)) {
+               int i;
+               __u32 qlen = 0;
+               struct Qdisc *qdisc;
+               struct gnet_stats_queue qstats = {0};
+               struct gnet_stats_basic_packed bstats = {0};
+               struct netdev_tc_txq tc = dev->tc_to_txq[cl - 1];
+
+               /* Drop lock here it will be reclaimed before touching
+                * statistics this is required because the d->lock we
+                * hold here is the look on dev_queue->qdisc_sleeping
+                * also acquired below.
+                */
+               spin_unlock_bh(d->lock);
+
+               for (i = tc.offset; i < tc.offset + tc.count; i++) {
+                       struct netdev_queue *q = netdev_get_tx_queue(dev, i);
+
+                       qdisc = rtnl_dereference(q->qdisc);
+                       spin_lock_bh(qdisc_lock(qdisc));
+                       qlen              += qdisc->q.qlen;
+                       bstats.bytes      += qdisc->bstats.bytes;
+                       bstats.packets    += qdisc->bstats.packets;
+                       qstats.backlog    += qdisc->qstats.backlog;
+                       qstats.drops      += qdisc->qstats.drops;
+                       qstats.requeues   += qdisc->qstats.requeues;
+                       qstats.overlimits += qdisc->qstats.overlimits;
+                       spin_unlock_bh(qdisc_lock(qdisc));
+               }
+               /* Reclaim root sleeping lock before completing stats */
+               spin_lock_bh(d->lock);
+               if (gnet_stats_copy_basic(d, NULL, &bstats) < 0 ||
+                   gnet_stats_copy_queue(d, NULL, &qstats, qlen) < 0)
+                       return -1;
+       } else {
+               struct netdev_queue *dev_queue = mqprio_queue_get(sch, cl);
+
+               sch = dev_queue->qdisc_sleeping;
+               if (gnet_stats_copy_basic(d, NULL, &sch->bstats) < 0 ||
+                   gnet_stats_copy_queue(d, NULL,
+                                         &sch->qstats, sch->q.qlen) < 0)
+                       return -1;
+       }
+       return 0;
+}
+
+static void mqprio_walk(struct Qdisc *sch, struct qdisc_walker *arg)
+{
+       struct net_device *dev = qdisc_dev(sch);
+       unsigned long ntx;
+
+       if (arg->stop)
+               return;
+
+       /* Walk hierarchy with a virtual class per tc */
+       arg->count = arg->skip;
+       for (ntx = arg->skip;
+            ntx < dev->num_tx_queues + netdev_get_num_tc(dev);
+            ntx++) {
+               if (arg->fn(sch, ntx + 1, arg) < 0) {
+                       arg->stop = 1;
+                       break;
+               }
+               arg->count++;
+       }
+}
+
+static const struct Qdisc_class_ops mqprio_class_ops = {
+       .graft          = mqprio_graft,
+       .leaf           = mqprio_leaf,
+       .get            = mqprio_get,
+       .put            = mqprio_put,
+       .walk           = mqprio_walk,
+       .dump           = mqprio_dump_class,
+       .dump_stats     = mqprio_dump_class_stats,
+};
+
+static struct Qdisc_ops mqprio_qdisc_ops __read_mostly = {
+       .cl_ops         = &mqprio_class_ops,
+       .id             = "mqprio",
+       .priv_size      = sizeof(struct mqprio_sched),
+       .init           = mqprio_init,
+       .destroy        = mqprio_destroy,
+       .attach         = mqprio_attach,
+       .dump           = mqprio_dump,
+       .owner          = THIS_MODULE,
+};
+
+static int __init mqprio_module_init(void)
+{
+       return register_qdisc(&mqprio_qdisc_ops);
+}
+
+static void __exit mqprio_module_exit(void)
+{
+       unregister_qdisc(&mqprio_qdisc_ops);
+}
+
+module_init(mqprio_module_init);
+module_exit(mqprio_module_exit);
+
+MODULE_LICENSE("GPL");