| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * net/sched/sch_fq.c Fair Queue Packet Scheduler (per flow pacing) |
| * |
| * Copyright (C) 2013-2015 Eric Dumazet <edumazet@google.com> |
| * |
| * Meant to be mostly used for locally generated traffic : |
| * Fast classification depends on skb->sk being set before reaching us. |
| * If not, (router workload), we use rxhash as fallback, with 32 bits wide hash. |
| * All packets belonging to a socket are considered as a 'flow'. |
| * |
| * Flows are dynamically allocated and stored in a hash table of RB trees |
| * They are also part of one Round Robin 'queues' (new or old flows) |
| * |
| * Burst avoidance (aka pacing) capability : |
| * |
| * Transport (eg TCP) can set in sk->sk_pacing_rate a rate, enqueue a |
| * bunch of packets, and this packet scheduler adds delay between |
| * packets to respect rate limitation. |
| * |
| * enqueue() : |
| * - lookup one RB tree (out of 1024 or more) to find the flow. |
| * If non existent flow, create it, add it to the tree. |
| * Add skb to the per flow list of skb (fifo). |
| * - Use a special fifo for high prio packets |
| * |
| * dequeue() : serves flows in Round Robin |
| * Note : When a flow becomes empty, we do not immediately remove it from |
| * rb trees, for performance reasons (its expected to send additional packets, |
| * or SLAB cache will reuse socket for another flow) |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/types.h> |
| #include <linux/kernel.h> |
| #include <linux/jiffies.h> |
| #include <linux/string.h> |
| #include <linux/in.h> |
| #include <linux/errno.h> |
| #include <linux/init.h> |
| #include <linux/skbuff.h> |
| #include <linux/slab.h> |
| #include <linux/rbtree.h> |
| #include <linux/hash.h> |
| #include <linux/prefetch.h> |
| #include <linux/vmalloc.h> |
| #include <net/netlink.h> |
| #include <net/pkt_sched.h> |
| #include <net/sock.h> |
| #include <net/tcp_states.h> |
| #include <net/tcp.h> |
| |
| struct fq_skb_cb { |
| u64 time_to_send; |
| }; |
| |
| static inline struct fq_skb_cb *fq_skb_cb(struct sk_buff *skb) |
| { |
| qdisc_cb_private_validate(skb, sizeof(struct fq_skb_cb)); |
| return (struct fq_skb_cb *)qdisc_skb_cb(skb)->data; |
| } |
| |
| /* |
| * Per flow structure, dynamically allocated. |
| * If packets have monotically increasing time_to_send, they are placed in O(1) |
| * in linear list (head,tail), otherwise are placed in a rbtree (t_root). |
| */ |
| struct fq_flow { |
| struct rb_root t_root; |
| struct sk_buff *head; /* list of skbs for this flow : first skb */ |
| union { |
| struct sk_buff *tail; /* last skb in the list */ |
| unsigned long age; /* jiffies when flow was emptied, for gc */ |
| }; |
| struct rb_node fq_node; /* anchor in fq_root[] trees */ |
| struct sock *sk; |
| int qlen; /* number of packets in flow queue */ |
| int credit; |
| u32 socket_hash; /* sk_hash */ |
| struct fq_flow *next; /* next pointer in RR lists, or &detached */ |
| |
| struct rb_node rate_node; /* anchor in q->delayed tree */ |
| u64 time_next_packet; |
| }; |
| |
| struct fq_flow_head { |
| struct fq_flow *first; |
| struct fq_flow *last; |
| }; |
| |
| struct fq_sched_data { |
| struct fq_flow_head new_flows; |
| |
| struct fq_flow_head old_flows; |
| |
| struct rb_root delayed; /* for rate limited flows */ |
| u64 time_next_delayed_flow; |
| unsigned long unthrottle_latency_ns; |
| |
| struct fq_flow internal; /* for non classified or high prio packets */ |
| u32 quantum; |
| u32 initial_quantum; |
| u32 flow_refill_delay; |
| u32 flow_plimit; /* max packets per flow */ |
| unsigned long flow_max_rate; /* optional max rate per flow */ |
| u64 ce_threshold; |
| u32 orphan_mask; /* mask for orphaned skb */ |
| u32 low_rate_threshold; |
| struct rb_root *fq_root; |
| u8 rate_enable; |
| u8 fq_trees_log; |
| |
| u32 flows; |
| u32 inactive_flows; |
| u32 throttled_flows; |
| |
| u64 stat_gc_flows; |
| u64 stat_internal_packets; |
| u64 stat_throttled; |
| u64 stat_ce_mark; |
| u64 stat_flows_plimit; |
| u64 stat_pkts_too_long; |
| u64 stat_allocation_errors; |
| struct qdisc_watchdog watchdog; |
| }; |
| |
| /* special value to mark a detached flow (not on old/new list) */ |
| static struct fq_flow detached, throttled; |
| |
| static void fq_flow_set_detached(struct fq_flow *f) |
| { |
| f->next = &detached; |
| f->age = jiffies; |
| } |
| |
| static bool fq_flow_is_detached(const struct fq_flow *f) |
| { |
| return f->next == &detached; |
| } |
| |
| static bool fq_flow_is_throttled(const struct fq_flow *f) |
| { |
| return f->next == &throttled; |
| } |
| |
| static void fq_flow_add_tail(struct fq_flow_head *head, struct fq_flow *flow) |
| { |
| if (head->first) |
| head->last->next = flow; |
| else |
| head->first = flow; |
| head->last = flow; |
| flow->next = NULL; |
| } |
| |
| static void fq_flow_unset_throttled(struct fq_sched_data *q, struct fq_flow *f) |
| { |
| rb_erase(&f->rate_node, &q->delayed); |
| q->throttled_flows--; |
| fq_flow_add_tail(&q->old_flows, f); |
| } |
| |
| static void fq_flow_set_throttled(struct fq_sched_data *q, struct fq_flow *f) |
| { |
| struct rb_node **p = &q->delayed.rb_node, *parent = NULL; |
| |
| while (*p) { |
| struct fq_flow *aux; |
| |
| parent = *p; |
| aux = rb_entry(parent, struct fq_flow, rate_node); |
| if (f->time_next_packet >= aux->time_next_packet) |
| p = &parent->rb_right; |
| else |
| p = &parent->rb_left; |
| } |
| rb_link_node(&f->rate_node, parent, p); |
| rb_insert_color(&f->rate_node, &q->delayed); |
| q->throttled_flows++; |
| q->stat_throttled++; |
| |
| f->next = &throttled; |
| if (q->time_next_delayed_flow > f->time_next_packet) |
| q->time_next_delayed_flow = f->time_next_packet; |
| } |
| |
| |
| static struct kmem_cache *fq_flow_cachep __read_mostly; |
| |
| |
| /* limit number of collected flows per round */ |
| #define FQ_GC_MAX 8 |
| #define FQ_GC_AGE (3*HZ) |
| |
| static bool fq_gc_candidate(const struct fq_flow *f) |
| { |
| return fq_flow_is_detached(f) && |
| time_after(jiffies, f->age + FQ_GC_AGE); |
| } |
| |
| static void fq_gc(struct fq_sched_data *q, |
| struct rb_root *root, |
| struct sock *sk) |
| { |
| struct fq_flow *f, *tofree[FQ_GC_MAX]; |
| struct rb_node **p, *parent; |
| int fcnt = 0; |
| |
| p = &root->rb_node; |
| parent = NULL; |
| while (*p) { |
| parent = *p; |
| |
| f = rb_entry(parent, struct fq_flow, fq_node); |
| if (f->sk == sk) |
| break; |
| |
| if (fq_gc_candidate(f)) { |
| tofree[fcnt++] = f; |
| if (fcnt == FQ_GC_MAX) |
| break; |
| } |
| |
| if (f->sk > sk) |
| p = &parent->rb_right; |
| else |
| p = &parent->rb_left; |
| } |
| |
| q->flows -= fcnt; |
| q->inactive_flows -= fcnt; |
| q->stat_gc_flows += fcnt; |
| while (fcnt) { |
| struct fq_flow *f = tofree[--fcnt]; |
| |
| rb_erase(&f->fq_node, root); |
| kmem_cache_free(fq_flow_cachep, f); |
| } |
| } |
| |
| static struct fq_flow *fq_classify(struct sk_buff *skb, struct fq_sched_data *q) |
| { |
| struct rb_node **p, *parent; |
| struct sock *sk = skb->sk; |
| struct rb_root *root; |
| struct fq_flow *f; |
| |
| /* warning: no starvation prevention... */ |
| if (unlikely((skb->priority & TC_PRIO_MAX) == TC_PRIO_CONTROL)) |
| return &q->internal; |
| |
| /* SYNACK messages are attached to a TCP_NEW_SYN_RECV request socket |
| * or a listener (SYNCOOKIE mode) |
| * 1) request sockets are not full blown, |
| * they do not contain sk_pacing_rate |
| * 2) They are not part of a 'flow' yet |
| * 3) We do not want to rate limit them (eg SYNFLOOD attack), |
| * especially if the listener set SO_MAX_PACING_RATE |
| * 4) We pretend they are orphaned |
| */ |
| if (!sk || sk_listener(sk)) { |
| unsigned long hash = skb_get_hash(skb) & q->orphan_mask; |
| |
| /* By forcing low order bit to 1, we make sure to not |
| * collide with a local flow (socket pointers are word aligned) |
| */ |
| sk = (struct sock *)((hash << 1) | 1UL); |
| skb_orphan(skb); |
| } else if (sk->sk_state == TCP_CLOSE) { |
| unsigned long hash = skb_get_hash(skb) & q->orphan_mask; |
| /* |
| * Sockets in TCP_CLOSE are non connected. |
| * Typical use case is UDP sockets, they can send packets |
| * with sendto() to many different destinations. |
| * We probably could use a generic bit advertising |
| * non connected sockets, instead of sk_state == TCP_CLOSE, |
| * if we care enough. |
| */ |
| sk = (struct sock *)((hash << 1) | 1UL); |
| } |
| |
| root = &q->fq_root[hash_ptr(sk, q->fq_trees_log)]; |
| |
| if (q->flows >= (2U << q->fq_trees_log) && |
| q->inactive_flows > q->flows/2) |
| fq_gc(q, root, sk); |
| |
| p = &root->rb_node; |
| parent = NULL; |
| while (*p) { |
| parent = *p; |
| |
| f = rb_entry(parent, struct fq_flow, fq_node); |
| if (f->sk == sk) { |
| /* socket might have been reallocated, so check |
| * if its sk_hash is the same. |
| * It not, we need to refill credit with |
| * initial quantum |
| */ |
| if (unlikely(skb->sk == sk && |
| f->socket_hash != sk->sk_hash)) { |
| f->credit = q->initial_quantum; |
| f->socket_hash = sk->sk_hash; |
| if (q->rate_enable) |
| smp_store_release(&sk->sk_pacing_status, |
| SK_PACING_FQ); |
| if (fq_flow_is_throttled(f)) |
| fq_flow_unset_throttled(q, f); |
| f->time_next_packet = 0ULL; |
| } |
| return f; |
| } |
| if (f->sk > sk) |
| p = &parent->rb_right; |
| else |
| p = &parent->rb_left; |
| } |
| |
| f = kmem_cache_zalloc(fq_flow_cachep, GFP_ATOMIC | __GFP_NOWARN); |
| if (unlikely(!f)) { |
| q->stat_allocation_errors++; |
| return &q->internal; |
| } |
| /* f->t_root is already zeroed after kmem_cache_zalloc() */ |
| |
| fq_flow_set_detached(f); |
| f->sk = sk; |
| if (skb->sk == sk) { |
| f->socket_hash = sk->sk_hash; |
| if (q->rate_enable) |
| smp_store_release(&sk->sk_pacing_status, |
| SK_PACING_FQ); |
| } |
| f->credit = q->initial_quantum; |
| |
| rb_link_node(&f->fq_node, parent, p); |
| rb_insert_color(&f->fq_node, root); |
| |
| q->flows++; |
| q->inactive_flows++; |
| return f; |
| } |
| |
| static struct sk_buff *fq_peek(struct fq_flow *flow) |
| { |
| struct sk_buff *skb = skb_rb_first(&flow->t_root); |
| struct sk_buff *head = flow->head; |
| |
| if (!skb) |
| return head; |
| |
| if (!head) |
| return skb; |
| |
| if (fq_skb_cb(skb)->time_to_send < fq_skb_cb(head)->time_to_send) |
| return skb; |
| return head; |
| } |
| |
| static void fq_erase_head(struct Qdisc *sch, struct fq_flow *flow, |
| struct sk_buff *skb) |
| { |
| if (skb == flow->head) { |
| flow->head = skb->next; |
| } else { |
| rb_erase(&skb->rbnode, &flow->t_root); |
| skb->dev = qdisc_dev(sch); |
| } |
| } |
| |
| /* remove one skb from head of flow queue */ |
| static struct sk_buff *fq_dequeue_head(struct Qdisc *sch, struct fq_flow *flow) |
| { |
| struct sk_buff *skb = fq_peek(flow); |
| |
| if (skb) { |
| fq_erase_head(sch, flow, skb); |
| skb_mark_not_on_list(skb); |
| flow->qlen--; |
| qdisc_qstats_backlog_dec(sch, skb); |
| sch->q.qlen--; |
| } |
| return skb; |
| } |
| |
| static void flow_queue_add(struct fq_flow *flow, struct sk_buff *skb) |
| { |
| struct rb_node **p, *parent; |
| struct sk_buff *head, *aux; |
| |
| fq_skb_cb(skb)->time_to_send = skb->tstamp ?: ktime_get_ns(); |
| |
| head = flow->head; |
| if (!head || |
| fq_skb_cb(skb)->time_to_send >= fq_skb_cb(flow->tail)->time_to_send) { |
| if (!head) |
| flow->head = skb; |
| else |
| flow->tail->next = skb; |
| flow->tail = skb; |
| skb->next = NULL; |
| return; |
| } |
| |
| p = &flow->t_root.rb_node; |
| parent = NULL; |
| |
| while (*p) { |
| parent = *p; |
| aux = rb_to_skb(parent); |
| if (fq_skb_cb(skb)->time_to_send >= fq_skb_cb(aux)->time_to_send) |
| p = &parent->rb_right; |
| else |
| p = &parent->rb_left; |
| } |
| rb_link_node(&skb->rbnode, parent, p); |
| rb_insert_color(&skb->rbnode, &flow->t_root); |
| } |
| |
| static int fq_enqueue(struct sk_buff *skb, struct Qdisc *sch, |
| struct sk_buff **to_free) |
| { |
| struct fq_sched_data *q = qdisc_priv(sch); |
| struct fq_flow *f; |
| |
| if (unlikely(sch->q.qlen >= sch->limit)) |
| return qdisc_drop(skb, sch, to_free); |
| |
| f = fq_classify(skb, q); |
| if (unlikely(f->qlen >= q->flow_plimit && f != &q->internal)) { |
| q->stat_flows_plimit++; |
| return qdisc_drop(skb, sch, to_free); |
| } |
| |
| f->qlen++; |
| qdisc_qstats_backlog_inc(sch, skb); |
| if (fq_flow_is_detached(f)) { |
| fq_flow_add_tail(&q->new_flows, f); |
| if (time_after(jiffies, f->age + q->flow_refill_delay)) |
| f->credit = max_t(u32, f->credit, q->quantum); |
| q->inactive_flows--; |
| } |
| |
| /* Note: this overwrites f->age */ |
| flow_queue_add(f, skb); |
| |
| if (unlikely(f == &q->internal)) { |
| q->stat_internal_packets++; |
| } |
| sch->q.qlen++; |
| |
| return NET_XMIT_SUCCESS; |
| } |
| |
| static void fq_check_throttled(struct fq_sched_data *q, u64 now) |
| { |
| unsigned long sample; |
| struct rb_node *p; |
| |
| if (q->time_next_delayed_flow > now) |
| return; |
| |
| /* Update unthrottle latency EWMA. |
| * This is cheap and can help diagnosing timer/latency problems. |
| */ |
| sample = (unsigned long)(now - q->time_next_delayed_flow); |
| q->unthrottle_latency_ns -= q->unthrottle_latency_ns >> 3; |
| q->unthrottle_latency_ns += sample >> 3; |
| |
| q->time_next_delayed_flow = ~0ULL; |
| while ((p = rb_first(&q->delayed)) != NULL) { |
| struct fq_flow *f = rb_entry(p, struct fq_flow, rate_node); |
| |
| if (f->time_next_packet > now) { |
| q->time_next_delayed_flow = f->time_next_packet; |
| break; |
| } |
| fq_flow_unset_throttled(q, f); |
| } |
| } |
| |
| static struct sk_buff *fq_dequeue(struct Qdisc *sch) |
| { |
| struct fq_sched_data *q = qdisc_priv(sch); |
| struct fq_flow_head *head; |
| struct sk_buff *skb; |
| struct fq_flow *f; |
| unsigned long rate; |
| u32 plen; |
| u64 now; |
| |
| if (!sch->q.qlen) |
| return NULL; |
| |
| skb = fq_dequeue_head(sch, &q->internal); |
| if (skb) |
| goto out; |
| |
| now = ktime_get_ns(); |
| fq_check_throttled(q, now); |
| begin: |
| head = &q->new_flows; |
| if (!head->first) { |
| head = &q->old_flows; |
| if (!head->first) { |
| if (q->time_next_delayed_flow != ~0ULL) |
| qdisc_watchdog_schedule_ns(&q->watchdog, |
| q->time_next_delayed_flow); |
| return NULL; |
| } |
| } |
| f = head->first; |
| |
| if (f->credit <= 0) { |
| f->credit += q->quantum; |
| head->first = f->next; |
| fq_flow_add_tail(&q->old_flows, f); |
| goto begin; |
| } |
| |
| skb = fq_peek(f); |
| if (skb) { |
| u64 time_next_packet = max_t(u64, fq_skb_cb(skb)->time_to_send, |
| f->time_next_packet); |
| |
| if (now < time_next_packet) { |
| head->first = f->next; |
| f->time_next_packet = time_next_packet; |
| fq_flow_set_throttled(q, f); |
| goto begin; |
| } |
| if ((s64)(now - time_next_packet - q->ce_threshold) > 0) { |
| INET_ECN_set_ce(skb); |
| q->stat_ce_mark++; |
| } |
| } |
| |
| skb = fq_dequeue_head(sch, f); |
| if (!skb) { |
| head->first = f->next; |
| /* force a pass through old_flows to prevent starvation */ |
| if ((head == &q->new_flows) && q->old_flows.first) { |
| fq_flow_add_tail(&q->old_flows, f); |
| } else { |
| fq_flow_set_detached(f); |
| q->inactive_flows++; |
| } |
| goto begin; |
| } |
| prefetch(&skb->end); |
| plen = qdisc_pkt_len(skb); |
| f->credit -= plen; |
| |
| if (!q->rate_enable) |
| goto out; |
| |
| rate = q->flow_max_rate; |
| |
| /* If EDT time was provided for this skb, we need to |
| * update f->time_next_packet only if this qdisc enforces |
| * a flow max rate. |
| */ |
| if (!skb->tstamp) { |
| if (skb->sk) |
| rate = min(skb->sk->sk_pacing_rate, rate); |
| |
| if (rate <= q->low_rate_threshold) { |
| f->credit = 0; |
| } else { |
| plen = max(plen, q->quantum); |
| if (f->credit > 0) |
| goto out; |
| } |
| } |
| if (rate != ~0UL) { |
| u64 len = (u64)plen * NSEC_PER_SEC; |
| |
| if (likely(rate)) |
| len = div64_ul(len, rate); |
| /* Since socket rate can change later, |
| * clamp the delay to 1 second. |
| * Really, providers of too big packets should be fixed ! |
| */ |
| if (unlikely(len > NSEC_PER_SEC)) { |
| len = NSEC_PER_SEC; |
| q->stat_pkts_too_long++; |
| } |
| /* Account for schedule/timers drifts. |
| * f->time_next_packet was set when prior packet was sent, |
| * and current time (@now) can be too late by tens of us. |
| */ |
| if (f->time_next_packet) |
| len -= min(len/2, now - f->time_next_packet); |
| f->time_next_packet = now + len; |
| } |
| out: |
| qdisc_bstats_update(sch, skb); |
| return skb; |
| } |
| |
| static void fq_flow_purge(struct fq_flow *flow) |
| { |
| struct rb_node *p = rb_first(&flow->t_root); |
| |
| while (p) { |
| struct sk_buff *skb = rb_to_skb(p); |
| |
| p = rb_next(p); |
| rb_erase(&skb->rbnode, &flow->t_root); |
| rtnl_kfree_skbs(skb, skb); |
| } |
| rtnl_kfree_skbs(flow->head, flow->tail); |
| flow->head = NULL; |
| flow->qlen = 0; |
| } |
| |
| static void fq_reset(struct Qdisc *sch) |
| { |
| struct fq_sched_data *q = qdisc_priv(sch); |
| struct rb_root *root; |
| struct rb_node *p; |
| struct fq_flow *f; |
| unsigned int idx; |
| |
| sch->q.qlen = 0; |
| sch->qstats.backlog = 0; |
| |
| fq_flow_purge(&q->internal); |
| |
| if (!q->fq_root) |
| return; |
| |
| for (idx = 0; idx < (1U << q->fq_trees_log); idx++) { |
| root = &q->fq_root[idx]; |
| while ((p = rb_first(root)) != NULL) { |
| f = rb_entry(p, struct fq_flow, fq_node); |
| rb_erase(p, root); |
| |
| fq_flow_purge(f); |
| |
| kmem_cache_free(fq_flow_cachep, f); |
| } |
| } |
| q->new_flows.first = NULL; |
| q->old_flows.first = NULL; |
| q->delayed = RB_ROOT; |
| q->flows = 0; |
| q->inactive_flows = 0; |
| q->throttled_flows = 0; |
| } |
| |
| static void fq_rehash(struct fq_sched_data *q, |
| struct rb_root *old_array, u32 old_log, |
| struct rb_root *new_array, u32 new_log) |
| { |
| struct rb_node *op, **np, *parent; |
| struct rb_root *oroot, *nroot; |
| struct fq_flow *of, *nf; |
| int fcnt = 0; |
| u32 idx; |
| |
| for (idx = 0; idx < (1U << old_log); idx++) { |
| oroot = &old_array[idx]; |
| while ((op = rb_first(oroot)) != NULL) { |
| rb_erase(op, oroot); |
| of = rb_entry(op, struct fq_flow, fq_node); |
| if (fq_gc_candidate(of)) { |
| fcnt++; |
| kmem_cache_free(fq_flow_cachep, of); |
| continue; |
| } |
| nroot = &new_array[hash_ptr(of->sk, new_log)]; |
| |
| np = &nroot->rb_node; |
| parent = NULL; |
| while (*np) { |
| parent = *np; |
| |
| nf = rb_entry(parent, struct fq_flow, fq_node); |
| BUG_ON(nf->sk == of->sk); |
| |
| if (nf->sk > of->sk) |
| np = &parent->rb_right; |
| else |
| np = &parent->rb_left; |
| } |
| |
| rb_link_node(&of->fq_node, parent, np); |
| rb_insert_color(&of->fq_node, nroot); |
| } |
| } |
| q->flows -= fcnt; |
| q->inactive_flows -= fcnt; |
| q->stat_gc_flows += fcnt; |
| } |
| |
| static void fq_free(void *addr) |
| { |
| kvfree(addr); |
| } |
| |
| static int fq_resize(struct Qdisc *sch, u32 log) |
| { |
| struct fq_sched_data *q = qdisc_priv(sch); |
| struct rb_root *array; |
| void *old_fq_root; |
| u32 idx; |
| |
| if (q->fq_root && log == q->fq_trees_log) |
| return 0; |
| |
| /* If XPS was setup, we can allocate memory on right NUMA node */ |
| array = kvmalloc_node(sizeof(struct rb_root) << log, GFP_KERNEL | __GFP_RETRY_MAYFAIL, |
| netdev_queue_numa_node_read(sch->dev_queue)); |
| if (!array) |
| return -ENOMEM; |
| |
| for (idx = 0; idx < (1U << log); idx++) |
| array[idx] = RB_ROOT; |
| |
| sch_tree_lock(sch); |
| |
| old_fq_root = q->fq_root; |
| if (old_fq_root) |
| fq_rehash(q, old_fq_root, q->fq_trees_log, array, log); |
| |
| q->fq_root = array; |
| q->fq_trees_log = log; |
| |
| sch_tree_unlock(sch); |
| |
| fq_free(old_fq_root); |
| |
| return 0; |
| } |
| |
| static const struct nla_policy fq_policy[TCA_FQ_MAX + 1] = { |
| [TCA_FQ_PLIMIT] = { .type = NLA_U32 }, |
| [TCA_FQ_FLOW_PLIMIT] = { .type = NLA_U32 }, |
| [TCA_FQ_QUANTUM] = { .type = NLA_U32 }, |
| [TCA_FQ_INITIAL_QUANTUM] = { .type = NLA_U32 }, |
| [TCA_FQ_RATE_ENABLE] = { .type = NLA_U32 }, |
| [TCA_FQ_FLOW_DEFAULT_RATE] = { .type = NLA_U32 }, |
| [TCA_FQ_FLOW_MAX_RATE] = { .type = NLA_U32 }, |
| [TCA_FQ_BUCKETS_LOG] = { .type = NLA_U32 }, |
| [TCA_FQ_FLOW_REFILL_DELAY] = { .type = NLA_U32 }, |
| [TCA_FQ_ORPHAN_MASK] = { .type = NLA_U32 }, |
| [TCA_FQ_LOW_RATE_THRESHOLD] = { .type = NLA_U32 }, |
| [TCA_FQ_CE_THRESHOLD] = { .type = NLA_U32 }, |
| }; |
| |
| static int fq_change(struct Qdisc *sch, struct nlattr *opt, |
| struct netlink_ext_ack *extack) |
| { |
| struct fq_sched_data *q = qdisc_priv(sch); |
| struct nlattr *tb[TCA_FQ_MAX + 1]; |
| int err, drop_count = 0; |
| unsigned drop_len = 0; |
| u32 fq_log; |
| |
| if (!opt) |
| return -EINVAL; |
| |
| err = nla_parse_nested_deprecated(tb, TCA_FQ_MAX, opt, fq_policy, |
| NULL); |
| if (err < 0) |
| return err; |
| |
| sch_tree_lock(sch); |
| |
| fq_log = q->fq_trees_log; |
| |
| if (tb[TCA_FQ_BUCKETS_LOG]) { |
| u32 nval = nla_get_u32(tb[TCA_FQ_BUCKETS_LOG]); |
| |
| if (nval >= 1 && nval <= ilog2(256*1024)) |
| fq_log = nval; |
| else |
| err = -EINVAL; |
| } |
| if (tb[TCA_FQ_PLIMIT]) |
| sch->limit = nla_get_u32(tb[TCA_FQ_PLIMIT]); |
| |
| if (tb[TCA_FQ_FLOW_PLIMIT]) |
| q->flow_plimit = nla_get_u32(tb[TCA_FQ_FLOW_PLIMIT]); |
| |
| if (tb[TCA_FQ_QUANTUM]) { |
| u32 quantum = nla_get_u32(tb[TCA_FQ_QUANTUM]); |
| |
| if (quantum > 0 && quantum <= (1 << 20)) { |
| q->quantum = quantum; |
| } else { |
| NL_SET_ERR_MSG_MOD(extack, "invalid quantum"); |
| err = -EINVAL; |
| } |
| } |
| |
| if (tb[TCA_FQ_INITIAL_QUANTUM]) |
| q->initial_quantum = nla_get_u32(tb[TCA_FQ_INITIAL_QUANTUM]); |
| |
| if (tb[TCA_FQ_FLOW_DEFAULT_RATE]) |
| pr_warn_ratelimited("sch_fq: defrate %u ignored.\n", |
| nla_get_u32(tb[TCA_FQ_FLOW_DEFAULT_RATE])); |
| |
| if (tb[TCA_FQ_FLOW_MAX_RATE]) { |
| u32 rate = nla_get_u32(tb[TCA_FQ_FLOW_MAX_RATE]); |
| |
| q->flow_max_rate = (rate == ~0U) ? ~0UL : rate; |
| } |
| if (tb[TCA_FQ_LOW_RATE_THRESHOLD]) |
| q->low_rate_threshold = |
| nla_get_u32(tb[TCA_FQ_LOW_RATE_THRESHOLD]); |
| |
| if (tb[TCA_FQ_RATE_ENABLE]) { |
| u32 enable = nla_get_u32(tb[TCA_FQ_RATE_ENABLE]); |
| |
| if (enable <= 1) |
| q->rate_enable = enable; |
| else |
| err = -EINVAL; |
| } |
| |
| if (tb[TCA_FQ_FLOW_REFILL_DELAY]) { |
| u32 usecs_delay = nla_get_u32(tb[TCA_FQ_FLOW_REFILL_DELAY]) ; |
| |
| q->flow_refill_delay = usecs_to_jiffies(usecs_delay); |
| } |
| |
| if (tb[TCA_FQ_ORPHAN_MASK]) |
| q->orphan_mask = nla_get_u32(tb[TCA_FQ_ORPHAN_MASK]); |
| |
| if (tb[TCA_FQ_CE_THRESHOLD]) |
| q->ce_threshold = (u64)NSEC_PER_USEC * |
| nla_get_u32(tb[TCA_FQ_CE_THRESHOLD]); |
| |
| if (!err) { |
| sch_tree_unlock(sch); |
| err = fq_resize(sch, fq_log); |
| sch_tree_lock(sch); |
| } |
| while (sch->q.qlen > sch->limit) { |
| struct sk_buff *skb = fq_dequeue(sch); |
| |
| if (!skb) |
| break; |
| drop_len += qdisc_pkt_len(skb); |
| rtnl_kfree_skbs(skb, skb); |
| drop_count++; |
| } |
| qdisc_tree_reduce_backlog(sch, drop_count, drop_len); |
| |
| sch_tree_unlock(sch); |
| return err; |
| } |
| |
| static void fq_destroy(struct Qdisc *sch) |
| { |
| struct fq_sched_data *q = qdisc_priv(sch); |
| |
| fq_reset(sch); |
| fq_free(q->fq_root); |
| qdisc_watchdog_cancel(&q->watchdog); |
| } |
| |
| static int fq_init(struct Qdisc *sch, struct nlattr *opt, |
| struct netlink_ext_ack *extack) |
| { |
| struct fq_sched_data *q = qdisc_priv(sch); |
| int err; |
| |
| sch->limit = 10000; |
| q->flow_plimit = 100; |
| q->quantum = 2 * psched_mtu(qdisc_dev(sch)); |
| q->initial_quantum = 10 * psched_mtu(qdisc_dev(sch)); |
| q->flow_refill_delay = msecs_to_jiffies(40); |
| q->flow_max_rate = ~0UL; |
| q->time_next_delayed_flow = ~0ULL; |
| q->rate_enable = 1; |
| q->new_flows.first = NULL; |
| q->old_flows.first = NULL; |
| q->delayed = RB_ROOT; |
| q->fq_root = NULL; |
| q->fq_trees_log = ilog2(1024); |
| q->orphan_mask = 1024 - 1; |
| q->low_rate_threshold = 550000 / 8; |
| |
| /* Default ce_threshold of 4294 seconds */ |
| q->ce_threshold = (u64)NSEC_PER_USEC * ~0U; |
| |
| qdisc_watchdog_init_clockid(&q->watchdog, sch, CLOCK_MONOTONIC); |
| |
| if (opt) |
| err = fq_change(sch, opt, extack); |
| else |
| err = fq_resize(sch, q->fq_trees_log); |
| |
| return err; |
| } |
| |
| static int fq_dump(struct Qdisc *sch, struct sk_buff *skb) |
| { |
| struct fq_sched_data *q = qdisc_priv(sch); |
| u64 ce_threshold = q->ce_threshold; |
| struct nlattr *opts; |
| |
| opts = nla_nest_start_noflag(skb, TCA_OPTIONS); |
| if (opts == NULL) |
| goto nla_put_failure; |
| |
| /* TCA_FQ_FLOW_DEFAULT_RATE is not used anymore */ |
| |
| do_div(ce_threshold, NSEC_PER_USEC); |
| |
| if (nla_put_u32(skb, TCA_FQ_PLIMIT, sch->limit) || |
| nla_put_u32(skb, TCA_FQ_FLOW_PLIMIT, q->flow_plimit) || |
| nla_put_u32(skb, TCA_FQ_QUANTUM, q->quantum) || |
| nla_put_u32(skb, TCA_FQ_INITIAL_QUANTUM, q->initial_quantum) || |
| nla_put_u32(skb, TCA_FQ_RATE_ENABLE, q->rate_enable) || |
| nla_put_u32(skb, TCA_FQ_FLOW_MAX_RATE, |
| min_t(unsigned long, q->flow_max_rate, ~0U)) || |
| nla_put_u32(skb, TCA_FQ_FLOW_REFILL_DELAY, |
| jiffies_to_usecs(q->flow_refill_delay)) || |
| nla_put_u32(skb, TCA_FQ_ORPHAN_MASK, q->orphan_mask) || |
| nla_put_u32(skb, TCA_FQ_LOW_RATE_THRESHOLD, |
| q->low_rate_threshold) || |
| nla_put_u32(skb, TCA_FQ_CE_THRESHOLD, (u32)ce_threshold) || |
| nla_put_u32(skb, TCA_FQ_BUCKETS_LOG, q->fq_trees_log)) |
| goto nla_put_failure; |
| |
| return nla_nest_end(skb, opts); |
| |
| nla_put_failure: |
| return -1; |
| } |
| |
| static int fq_dump_stats(struct Qdisc *sch, struct gnet_dump *d) |
| { |
| struct fq_sched_data *q = qdisc_priv(sch); |
| struct tc_fq_qd_stats st; |
| |
| sch_tree_lock(sch); |
| |
| st.gc_flows = q->stat_gc_flows; |
| st.highprio_packets = q->stat_internal_packets; |
| st.tcp_retrans = 0; |
| st.throttled = q->stat_throttled; |
| st.flows_plimit = q->stat_flows_plimit; |
| st.pkts_too_long = q->stat_pkts_too_long; |
| st.allocation_errors = q->stat_allocation_errors; |
| st.time_next_delayed_flow = q->time_next_delayed_flow - ktime_get_ns(); |
| st.flows = q->flows; |
| st.inactive_flows = q->inactive_flows; |
| st.throttled_flows = q->throttled_flows; |
| st.unthrottle_latency_ns = min_t(unsigned long, |
| q->unthrottle_latency_ns, ~0U); |
| st.ce_mark = q->stat_ce_mark; |
| sch_tree_unlock(sch); |
| |
| return gnet_stats_copy_app(d, &st, sizeof(st)); |
| } |
| |
| static struct Qdisc_ops fq_qdisc_ops __read_mostly = { |
| .id = "fq", |
| .priv_size = sizeof(struct fq_sched_data), |
| |
| .enqueue = fq_enqueue, |
| .dequeue = fq_dequeue, |
| .peek = qdisc_peek_dequeued, |
| .init = fq_init, |
| .reset = fq_reset, |
| .destroy = fq_destroy, |
| .change = fq_change, |
| .dump = fq_dump, |
| .dump_stats = fq_dump_stats, |
| .owner = THIS_MODULE, |
| }; |
| |
| static int __init fq_module_init(void) |
| { |
| int ret; |
| |
| fq_flow_cachep = kmem_cache_create("fq_flow_cache", |
| sizeof(struct fq_flow), |
| 0, 0, NULL); |
| if (!fq_flow_cachep) |
| return -ENOMEM; |
| |
| ret = register_qdisc(&fq_qdisc_ops); |
| if (ret) |
| kmem_cache_destroy(fq_flow_cachep); |
| return ret; |
| } |
| |
| static void __exit fq_module_exit(void) |
| { |
| unregister_qdisc(&fq_qdisc_ops); |
| kmem_cache_destroy(fq_flow_cachep); |
| } |
| |
| module_init(fq_module_init) |
| module_exit(fq_module_exit) |
| MODULE_AUTHOR("Eric Dumazet"); |
| MODULE_LICENSE("GPL"); |