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-rw-r--r--net/sched/sch_multiq.c412
1 files changed, 412 insertions, 0 deletions
diff --git a/net/sched/sch_multiq.c b/net/sched/sch_multiq.c
new file mode 100644
index 0000000000..75c9c86018
--- /dev/null
+++ b/net/sched/sch_multiq.c
@@ -0,0 +1,412 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2008, Intel Corporation.
+ *
+ * Author: Alexander Duyck <alexander.h.duyck@intel.com>
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/skbuff.h>
+#include <net/netlink.h>
+#include <net/pkt_sched.h>
+#include <net/pkt_cls.h>
+
+struct multiq_sched_data {
+ u16 bands;
+ u16 max_bands;
+ u16 curband;
+ struct tcf_proto __rcu *filter_list;
+ struct tcf_block *block;
+ struct Qdisc **queues;
+};
+
+
+static struct Qdisc *
+multiq_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
+{
+ struct multiq_sched_data *q = qdisc_priv(sch);
+ u32 band;
+ struct tcf_result res;
+ struct tcf_proto *fl = rcu_dereference_bh(q->filter_list);
+ int err;
+
+ *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
+ err = tcf_classify(skb, NULL, fl, &res, false);
+#ifdef CONFIG_NET_CLS_ACT
+ switch (err) {
+ case TC_ACT_STOLEN:
+ case TC_ACT_QUEUED:
+ case TC_ACT_TRAP:
+ *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
+ fallthrough;
+ case TC_ACT_SHOT:
+ return NULL;
+ }
+#endif
+ band = skb_get_queue_mapping(skb);
+
+ if (band >= q->bands)
+ return q->queues[0];
+
+ return q->queues[band];
+}
+
+static int
+multiq_enqueue(struct sk_buff *skb, struct Qdisc *sch,
+ struct sk_buff **to_free)
+{
+ struct Qdisc *qdisc;
+ int ret;
+
+ qdisc = multiq_classify(skb, sch, &ret);
+#ifdef CONFIG_NET_CLS_ACT
+ if (qdisc == NULL) {
+
+ if (ret & __NET_XMIT_BYPASS)
+ qdisc_qstats_drop(sch);
+ __qdisc_drop(skb, to_free);
+ return ret;
+ }
+#endif
+
+ ret = qdisc_enqueue(skb, qdisc, to_free);
+ if (ret == NET_XMIT_SUCCESS) {
+ sch->q.qlen++;
+ return NET_XMIT_SUCCESS;
+ }
+ if (net_xmit_drop_count(ret))
+ qdisc_qstats_drop(sch);
+ return ret;
+}
+
+static struct sk_buff *multiq_dequeue(struct Qdisc *sch)
+{
+ struct multiq_sched_data *q = qdisc_priv(sch);
+ struct Qdisc *qdisc;
+ struct sk_buff *skb;
+ int band;
+
+ for (band = 0; band < q->bands; band++) {
+ /* cycle through bands to ensure fairness */
+ q->curband++;
+ if (q->curband >= q->bands)
+ q->curband = 0;
+
+ /* Check that target subqueue is available before
+ * pulling an skb to avoid head-of-line blocking.
+ */
+ if (!netif_xmit_stopped(
+ netdev_get_tx_queue(qdisc_dev(sch), q->curband))) {
+ qdisc = q->queues[q->curband];
+ skb = qdisc->dequeue(qdisc);
+ if (skb) {
+ qdisc_bstats_update(sch, skb);
+ sch->q.qlen--;
+ return skb;
+ }
+ }
+ }
+ return NULL;
+
+}
+
+static struct sk_buff *multiq_peek(struct Qdisc *sch)
+{
+ struct multiq_sched_data *q = qdisc_priv(sch);
+ unsigned int curband = q->curband;
+ struct Qdisc *qdisc;
+ struct sk_buff *skb;
+ int band;
+
+ for (band = 0; band < q->bands; band++) {
+ /* cycle through bands to ensure fairness */
+ curband++;
+ if (curband >= q->bands)
+ curband = 0;
+
+ /* Check that target subqueue is available before
+ * pulling an skb to avoid head-of-line blocking.
+ */
+ if (!netif_xmit_stopped(
+ netdev_get_tx_queue(qdisc_dev(sch), curband))) {
+ qdisc = q->queues[curband];
+ skb = qdisc->ops->peek(qdisc);
+ if (skb)
+ return skb;
+ }
+ }
+ return NULL;
+
+}
+
+static void
+multiq_reset(struct Qdisc *sch)
+{
+ u16 band;
+ struct multiq_sched_data *q = qdisc_priv(sch);
+
+ for (band = 0; band < q->bands; band++)
+ qdisc_reset(q->queues[band]);
+ q->curband = 0;
+}
+
+static void
+multiq_destroy(struct Qdisc *sch)
+{
+ int band;
+ struct multiq_sched_data *q = qdisc_priv(sch);
+
+ tcf_block_put(q->block);
+ for (band = 0; band < q->bands; band++)
+ qdisc_put(q->queues[band]);
+
+ kfree(q->queues);
+}
+
+static int multiq_tune(struct Qdisc *sch, struct nlattr *opt,
+ struct netlink_ext_ack *extack)
+{
+ struct multiq_sched_data *q = qdisc_priv(sch);
+ struct tc_multiq_qopt *qopt;
+ struct Qdisc **removed;
+ int i, n_removed = 0;
+
+ if (!netif_is_multiqueue(qdisc_dev(sch)))
+ return -EOPNOTSUPP;
+ if (nla_len(opt) < sizeof(*qopt))
+ return -EINVAL;
+
+ qopt = nla_data(opt);
+
+ qopt->bands = qdisc_dev(sch)->real_num_tx_queues;
+
+ removed = kmalloc(sizeof(*removed) * (q->max_bands - q->bands),
+ GFP_KERNEL);
+ if (!removed)
+ return -ENOMEM;
+
+ sch_tree_lock(sch);
+ q->bands = qopt->bands;
+ for (i = q->bands; i < q->max_bands; i++) {
+ if (q->queues[i] != &noop_qdisc) {
+ struct Qdisc *child = q->queues[i];
+
+ q->queues[i] = &noop_qdisc;
+ qdisc_purge_queue(child);
+ removed[n_removed++] = child;
+ }
+ }
+
+ sch_tree_unlock(sch);
+
+ for (i = 0; i < n_removed; i++)
+ qdisc_put(removed[i]);
+ kfree(removed);
+
+ for (i = 0; i < q->bands; i++) {
+ if (q->queues[i] == &noop_qdisc) {
+ struct Qdisc *child, *old;
+ child = qdisc_create_dflt(sch->dev_queue,
+ &pfifo_qdisc_ops,
+ TC_H_MAKE(sch->handle,
+ i + 1), extack);
+ if (child) {
+ sch_tree_lock(sch);
+ old = q->queues[i];
+ q->queues[i] = child;
+ if (child != &noop_qdisc)
+ qdisc_hash_add(child, true);
+
+ if (old != &noop_qdisc)
+ qdisc_purge_queue(old);
+ sch_tree_unlock(sch);
+ qdisc_put(old);
+ }
+ }
+ }
+ return 0;
+}
+
+static int multiq_init(struct Qdisc *sch, struct nlattr *opt,
+ struct netlink_ext_ack *extack)
+{
+ struct multiq_sched_data *q = qdisc_priv(sch);
+ int i, err;
+
+ q->queues = NULL;
+
+ if (!opt)
+ return -EINVAL;
+
+ err = tcf_block_get(&q->block, &q->filter_list, sch, extack);
+ if (err)
+ return err;
+
+ q->max_bands = qdisc_dev(sch)->num_tx_queues;
+
+ q->queues = kcalloc(q->max_bands, sizeof(struct Qdisc *), GFP_KERNEL);
+ if (!q->queues)
+ return -ENOBUFS;
+ for (i = 0; i < q->max_bands; i++)
+ q->queues[i] = &noop_qdisc;
+
+ return multiq_tune(sch, opt, extack);
+}
+
+static int multiq_dump(struct Qdisc *sch, struct sk_buff *skb)
+{
+ struct multiq_sched_data *q = qdisc_priv(sch);
+ unsigned char *b = skb_tail_pointer(skb);
+ struct tc_multiq_qopt opt;
+
+ opt.bands = q->bands;
+ opt.max_bands = q->max_bands;
+
+ 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 int multiq_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
+ struct Qdisc **old, struct netlink_ext_ack *extack)
+{
+ struct multiq_sched_data *q = qdisc_priv(sch);
+ unsigned long band = arg - 1;
+
+ if (new == NULL)
+ new = &noop_qdisc;
+
+ *old = qdisc_replace(sch, new, &q->queues[band]);
+ return 0;
+}
+
+static struct Qdisc *
+multiq_leaf(struct Qdisc *sch, unsigned long arg)
+{
+ struct multiq_sched_data *q = qdisc_priv(sch);
+ unsigned long band = arg - 1;
+
+ return q->queues[band];
+}
+
+static unsigned long multiq_find(struct Qdisc *sch, u32 classid)
+{
+ struct multiq_sched_data *q = qdisc_priv(sch);
+ unsigned long band = TC_H_MIN(classid);
+
+ if (band - 1 >= q->bands)
+ return 0;
+ return band;
+}
+
+static unsigned long multiq_bind(struct Qdisc *sch, unsigned long parent,
+ u32 classid)
+{
+ return multiq_find(sch, classid);
+}
+
+
+static void multiq_unbind(struct Qdisc *q, unsigned long cl)
+{
+}
+
+static int multiq_dump_class(struct Qdisc *sch, unsigned long cl,
+ struct sk_buff *skb, struct tcmsg *tcm)
+{
+ struct multiq_sched_data *q = qdisc_priv(sch);
+
+ tcm->tcm_handle |= TC_H_MIN(cl);
+ tcm->tcm_info = q->queues[cl - 1]->handle;
+ return 0;
+}
+
+static int multiq_dump_class_stats(struct Qdisc *sch, unsigned long cl,
+ struct gnet_dump *d)
+{
+ struct multiq_sched_data *q = qdisc_priv(sch);
+ struct Qdisc *cl_q;
+
+ cl_q = q->queues[cl - 1];
+ if (gnet_stats_copy_basic(d, cl_q->cpu_bstats, &cl_q->bstats, true) < 0 ||
+ qdisc_qstats_copy(d, cl_q) < 0)
+ return -1;
+
+ return 0;
+}
+
+static void multiq_walk(struct Qdisc *sch, struct qdisc_walker *arg)
+{
+ struct multiq_sched_data *q = qdisc_priv(sch);
+ int band;
+
+ if (arg->stop)
+ return;
+
+ for (band = 0; band < q->bands; band++) {
+ if (!tc_qdisc_stats_dump(sch, band + 1, arg))
+ break;
+ }
+}
+
+static struct tcf_block *multiq_tcf_block(struct Qdisc *sch, unsigned long cl,
+ struct netlink_ext_ack *extack)
+{
+ struct multiq_sched_data *q = qdisc_priv(sch);
+
+ if (cl)
+ return NULL;
+ return q->block;
+}
+
+static const struct Qdisc_class_ops multiq_class_ops = {
+ .graft = multiq_graft,
+ .leaf = multiq_leaf,
+ .find = multiq_find,
+ .walk = multiq_walk,
+ .tcf_block = multiq_tcf_block,
+ .bind_tcf = multiq_bind,
+ .unbind_tcf = multiq_unbind,
+ .dump = multiq_dump_class,
+ .dump_stats = multiq_dump_class_stats,
+};
+
+static struct Qdisc_ops multiq_qdisc_ops __read_mostly = {
+ .next = NULL,
+ .cl_ops = &multiq_class_ops,
+ .id = "multiq",
+ .priv_size = sizeof(struct multiq_sched_data),
+ .enqueue = multiq_enqueue,
+ .dequeue = multiq_dequeue,
+ .peek = multiq_peek,
+ .init = multiq_init,
+ .reset = multiq_reset,
+ .destroy = multiq_destroy,
+ .change = multiq_tune,
+ .dump = multiq_dump,
+ .owner = THIS_MODULE,
+};
+
+static int __init multiq_module_init(void)
+{
+ return register_qdisc(&multiq_qdisc_ops);
+}
+
+static void __exit multiq_module_exit(void)
+{
+ unregister_qdisc(&multiq_qdisc_ops);
+}
+
+module_init(multiq_module_init)
+module_exit(multiq_module_exit)
+
+MODULE_LICENSE("GPL");