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-rw-r--r--net/sched/sch_mq.c275
1 files changed, 275 insertions, 0 deletions
diff --git a/net/sched/sch_mq.c b/net/sched/sch_mq.c
new file mode 100644
index 0000000000..c860119a8f
--- /dev/null
+++ b/net/sched/sch_mq.c
@@ -0,0 +1,275 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * net/sched/sch_mq.c Classful multiqueue dummy scheduler
+ *
+ * Copyright (c) 2009 Patrick McHardy <kaber@trash.net>
+ */
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/skbuff.h>
+#include <net/netlink.h>
+#include <net/pkt_cls.h>
+#include <net/pkt_sched.h>
+#include <net/sch_generic.h>
+
+struct mq_sched {
+ struct Qdisc **qdiscs;
+};
+
+static int mq_offload(struct Qdisc *sch, enum tc_mq_command cmd)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ struct tc_mq_qopt_offload opt = {
+ .command = cmd,
+ .handle = sch->handle,
+ };
+
+ if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
+ return -EOPNOTSUPP;
+
+ return dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_MQ, &opt);
+}
+
+static int mq_offload_stats(struct Qdisc *sch)
+{
+ struct tc_mq_qopt_offload opt = {
+ .command = TC_MQ_STATS,
+ .handle = sch->handle,
+ .stats = {
+ .bstats = &sch->bstats,
+ .qstats = &sch->qstats,
+ },
+ };
+
+ return qdisc_offload_dump_helper(sch, TC_SETUP_QDISC_MQ, &opt);
+}
+
+static void mq_destroy(struct Qdisc *sch)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ struct mq_sched *priv = qdisc_priv(sch);
+ unsigned int ntx;
+
+ mq_offload(sch, TC_MQ_DESTROY);
+
+ if (!priv->qdiscs)
+ return;
+ for (ntx = 0; ntx < dev->num_tx_queues && priv->qdiscs[ntx]; ntx++)
+ qdisc_put(priv->qdiscs[ntx]);
+ kfree(priv->qdiscs);
+}
+
+static int mq_init(struct Qdisc *sch, struct nlattr *opt,
+ struct netlink_ext_ack *extack)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ struct mq_sched *priv = qdisc_priv(sch);
+ struct netdev_queue *dev_queue;
+ struct Qdisc *qdisc;
+ unsigned int ntx;
+
+ if (sch->parent != TC_H_ROOT)
+ return -EOPNOTSUPP;
+
+ if (!netif_is_multiqueue(dev))
+ return -EOPNOTSUPP;
+
+ /* pre-allocate qdiscs, attachment can't fail */
+ priv->qdiscs = kcalloc(dev->num_tx_queues, sizeof(priv->qdiscs[0]),
+ GFP_KERNEL);
+ if (!priv->qdiscs)
+ return -ENOMEM;
+
+ for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
+ dev_queue = netdev_get_tx_queue(dev, ntx);
+ qdisc = qdisc_create_dflt(dev_queue, get_default_qdisc_ops(dev, ntx),
+ TC_H_MAKE(TC_H_MAJ(sch->handle),
+ TC_H_MIN(ntx + 1)),
+ extack);
+ if (!qdisc)
+ return -ENOMEM;
+ priv->qdiscs[ntx] = qdisc;
+ qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
+ }
+
+ sch->flags |= TCQ_F_MQROOT;
+
+ mq_offload(sch, TC_MQ_CREATE);
+ return 0;
+}
+
+static void mq_attach(struct Qdisc *sch)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ struct mq_sched *priv = qdisc_priv(sch);
+ struct Qdisc *qdisc, *old;
+ unsigned int ntx;
+
+ for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
+ qdisc = priv->qdiscs[ntx];
+ old = dev_graft_qdisc(qdisc->dev_queue, qdisc);
+ if (old)
+ qdisc_put(old);
+#ifdef CONFIG_NET_SCHED
+ if (ntx < dev->real_num_tx_queues)
+ qdisc_hash_add(qdisc, false);
+#endif
+
+ }
+ kfree(priv->qdiscs);
+ priv->qdiscs = NULL;
+}
+
+static int mq_dump(struct Qdisc *sch, struct sk_buff *skb)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ struct Qdisc *qdisc;
+ unsigned int ntx;
+
+ sch->q.qlen = 0;
+ gnet_stats_basic_sync_init(&sch->bstats);
+ memset(&sch->qstats, 0, sizeof(sch->qstats));
+
+ /* MQ supports lockless qdiscs. However, statistics accounting needs
+ * to account for all, none, or a mix of locked and unlocked child
+ * qdiscs. Percpu stats are added to counters in-band and locking
+ * qdisc totals are added at end.
+ */
+ for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
+ qdisc = rtnl_dereference(netdev_get_tx_queue(dev, ntx)->qdisc_sleeping);
+ spin_lock_bh(qdisc_lock(qdisc));
+
+ gnet_stats_add_basic(&sch->bstats, qdisc->cpu_bstats,
+ &qdisc->bstats, false);
+ gnet_stats_add_queue(&sch->qstats, qdisc->cpu_qstats,
+ &qdisc->qstats);
+ sch->q.qlen += qdisc_qlen(qdisc);
+
+ spin_unlock_bh(qdisc_lock(qdisc));
+ }
+
+ return mq_offload_stats(sch);
+}
+
+static struct netdev_queue *mq_queue_get(struct Qdisc *sch, unsigned long cl)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ unsigned long ntx = cl - 1;
+
+ if (ntx >= dev->num_tx_queues)
+ return NULL;
+ return netdev_get_tx_queue(dev, ntx);
+}
+
+static struct netdev_queue *mq_select_queue(struct Qdisc *sch,
+ struct tcmsg *tcm)
+{
+ return mq_queue_get(sch, TC_H_MIN(tcm->tcm_parent));
+}
+
+static int mq_graft(struct Qdisc *sch, unsigned long cl, struct Qdisc *new,
+ struct Qdisc **old, struct netlink_ext_ack *extack)
+{
+ struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
+ struct tc_mq_qopt_offload graft_offload;
+ struct net_device *dev = qdisc_dev(sch);
+
+ if (dev->flags & IFF_UP)
+ dev_deactivate(dev);
+
+ *old = dev_graft_qdisc(dev_queue, new);
+ if (new)
+ new->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
+ if (dev->flags & IFF_UP)
+ dev_activate(dev);
+
+ graft_offload.handle = sch->handle;
+ graft_offload.graft_params.queue = cl - 1;
+ graft_offload.graft_params.child_handle = new ? new->handle : 0;
+ graft_offload.command = TC_MQ_GRAFT;
+
+ qdisc_offload_graft_helper(qdisc_dev(sch), sch, new, *old,
+ TC_SETUP_QDISC_MQ, &graft_offload, extack);
+ return 0;
+}
+
+static struct Qdisc *mq_leaf(struct Qdisc *sch, unsigned long cl)
+{
+ struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
+
+ return rtnl_dereference(dev_queue->qdisc_sleeping);
+}
+
+static unsigned long mq_find(struct Qdisc *sch, u32 classid)
+{
+ unsigned int ntx = TC_H_MIN(classid);
+
+ if (!mq_queue_get(sch, ntx))
+ return 0;
+ return ntx;
+}
+
+static int mq_dump_class(struct Qdisc *sch, unsigned long cl,
+ struct sk_buff *skb, struct tcmsg *tcm)
+{
+ struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
+
+ tcm->tcm_parent = TC_H_ROOT;
+ tcm->tcm_handle |= TC_H_MIN(cl);
+ tcm->tcm_info = rtnl_dereference(dev_queue->qdisc_sleeping)->handle;
+ return 0;
+}
+
+static int mq_dump_class_stats(struct Qdisc *sch, unsigned long cl,
+ struct gnet_dump *d)
+{
+ struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
+
+ sch = rtnl_dereference(dev_queue->qdisc_sleeping);
+ if (gnet_stats_copy_basic(d, sch->cpu_bstats, &sch->bstats, true) < 0 ||
+ qdisc_qstats_copy(d, sch) < 0)
+ return -1;
+ return 0;
+}
+
+static void mq_walk(struct Qdisc *sch, struct qdisc_walker *arg)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ unsigned int ntx;
+
+ if (arg->stop)
+ return;
+
+ arg->count = arg->skip;
+ for (ntx = arg->skip; ntx < dev->num_tx_queues; ntx++) {
+ if (!tc_qdisc_stats_dump(sch, ntx + 1, arg))
+ break;
+ }
+}
+
+static const struct Qdisc_class_ops mq_class_ops = {
+ .select_queue = mq_select_queue,
+ .graft = mq_graft,
+ .leaf = mq_leaf,
+ .find = mq_find,
+ .walk = mq_walk,
+ .dump = mq_dump_class,
+ .dump_stats = mq_dump_class_stats,
+};
+
+struct Qdisc_ops mq_qdisc_ops __read_mostly = {
+ .cl_ops = &mq_class_ops,
+ .id = "mq",
+ .priv_size = sizeof(struct mq_sched),
+ .init = mq_init,
+ .destroy = mq_destroy,
+ .attach = mq_attach,
+ .change_real_num_tx = mq_change_real_num_tx,
+ .dump = mq_dump,
+ .owner = THIS_MODULE,
+};