alistair23-linux/net/sched/sch_fq_codel.c
Linus Torvalds 47ec5303d7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:

 1) Support 6Ghz band in ath11k driver, from Rajkumar Manoharan.

 2) Support UDP segmentation in code TSO code, from Eric Dumazet.

 3) Allow flashing different flash images in cxgb4 driver, from Vishal
    Kulkarni.

 4) Add drop frames counter and flow status to tc flower offloading,
    from Po Liu.

 5) Support n-tuple filters in cxgb4, from Vishal Kulkarni.

 6) Various new indirect call avoidance, from Eric Dumazet and Brian
    Vazquez.

 7) Fix BPF verifier failures on 32-bit pointer arithmetic, from
    Yonghong Song.

 8) Support querying and setting hardware address of a port function via
    devlink, use this in mlx5, from Parav Pandit.

 9) Support hw ipsec offload on bonding slaves, from Jarod Wilson.

10) Switch qca8k driver over to phylink, from Jonathan McDowell.

11) In bpftool, show list of processes holding BPF FD references to
    maps, programs, links, and btf objects. From Andrii Nakryiko.

12) Several conversions over to generic power management, from Vaibhav
    Gupta.

13) Add support for SO_KEEPALIVE et al. to bpf_setsockopt(), from Dmitry
    Yakunin.

14) Various https url conversions, from Alexander A. Klimov.

15) Timestamping and PHC support for mscc PHY driver, from Antoine
    Tenart.

16) Support bpf iterating over tcp and udp sockets, from Yonghong Song.

17) Support 5GBASE-T i40e NICs, from Aleksandr Loktionov.

18) Add kTLS RX HW offload support to mlx5e, from Tariq Toukan.

19) Fix the ->ndo_start_xmit() return type to be netdev_tx_t in several
    drivers. From Luc Van Oostenryck.

20) XDP support for xen-netfront, from Denis Kirjanov.

21) Support receive buffer autotuning in MPTCP, from Florian Westphal.

22) Support EF100 chip in sfc driver, from Edward Cree.

23) Add XDP support to mvpp2 driver, from Matteo Croce.

24) Support MPTCP in sock_diag, from Paolo Abeni.

25) Commonize UDP tunnel offloading code by creating udp_tunnel_nic
    infrastructure, from Jakub Kicinski.

26) Several pci_ --> dma_ API conversions, from Christophe JAILLET.

27) Add FLOW_ACTION_POLICE support to mlxsw, from Ido Schimmel.

28) Add SK_LOOKUP bpf program type, from Jakub Sitnicki.

29) Refactor a lot of networking socket option handling code in order to
    avoid set_fs() calls, from Christoph Hellwig.

30) Add rfc4884 support to icmp code, from Willem de Bruijn.

31) Support TBF offload in dpaa2-eth driver, from Ioana Ciornei.

32) Support XDP_REDIRECT in qede driver, from Alexander Lobakin.

33) Support PCI relaxed ordering in mlx5 driver, from Aya Levin.

34) Support TCP syncookies in MPTCP, from Flowian Westphal.

35) Fix several tricky cases of PMTU handling wrt. briding, from Stefano
    Brivio.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2056 commits)
  net: thunderx: initialize VF's mailbox mutex before first usage
  usb: hso: remove bogus check for EINPROGRESS
  usb: hso: no complaint about kmalloc failure
  hso: fix bailout in error case of probe
  ip_tunnel_core: Fix build for archs without _HAVE_ARCH_IPV6_CSUM
  selftests/net: relax cpu affinity requirement in msg_zerocopy test
  mptcp: be careful on subflow creation
  selftests: rtnetlink: make kci_test_encap() return sub-test result
  selftests: rtnetlink: correct the final return value for the test
  net: dsa: sja1105: use detected device id instead of DT one on mismatch
  tipc: set ub->ifindex for local ipv6 address
  ipv6: add ipv6_dev_find()
  net: openvswitch: silence suspicious RCU usage warning
  Revert "vxlan: fix tos value before xmit"
  ptp: only allow phase values lower than 1 period
  farsync: switch from 'pci_' to 'dma_' API
  wan: wanxl: switch from 'pci_' to 'dma_' API
  hv_netvsc: do not use VF device if link is down
  dpaa2-eth: Fix passing zero to 'PTR_ERR' warning
  net: macb: Properly handle phylink on at91sam9x
  ...
2020-08-05 20:13:21 -07:00

725 lines
19 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Fair Queue CoDel discipline
*
* Copyright (C) 2012,2015 Eric Dumazet <edumazet@google.com>
*/
#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/vmalloc.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <net/pkt_cls.h>
#include <net/codel.h>
#include <net/codel_impl.h>
#include <net/codel_qdisc.h>
/* Fair Queue CoDel.
*
* Principles :
* Packets are classified (internal classifier or external) on flows.
* This is a Stochastic model (as we use a hash, several flows
* might be hashed on same slot)
* Each flow has a CoDel managed queue.
* Flows are linked onto two (Round Robin) lists,
* so that new flows have priority on old ones.
*
* For a given flow, packets are not reordered (CoDel uses a FIFO)
* head drops only.
* ECN capability is on by default.
* Low memory footprint (64 bytes per flow)
*/
struct fq_codel_flow {
struct sk_buff *head;
struct sk_buff *tail;
struct list_head flowchain;
int deficit;
struct codel_vars cvars;
}; /* please try to keep this structure <= 64 bytes */
struct fq_codel_sched_data {
struct tcf_proto __rcu *filter_list; /* optional external classifier */
struct tcf_block *block;
struct fq_codel_flow *flows; /* Flows table [flows_cnt] */
u32 *backlogs; /* backlog table [flows_cnt] */
u32 flows_cnt; /* number of flows */
u32 quantum; /* psched_mtu(qdisc_dev(sch)); */
u32 drop_batch_size;
u32 memory_limit;
struct codel_params cparams;
struct codel_stats cstats;
u32 memory_usage;
u32 drop_overmemory;
u32 drop_overlimit;
u32 new_flow_count;
struct list_head new_flows; /* list of new flows */
struct list_head old_flows; /* list of old flows */
};
static unsigned int fq_codel_hash(const struct fq_codel_sched_data *q,
struct sk_buff *skb)
{
return reciprocal_scale(skb_get_hash(skb), q->flows_cnt);
}
static unsigned int fq_codel_classify(struct sk_buff *skb, struct Qdisc *sch,
int *qerr)
{
struct fq_codel_sched_data *q = qdisc_priv(sch);
struct tcf_proto *filter;
struct tcf_result res;
int result;
if (TC_H_MAJ(skb->priority) == sch->handle &&
TC_H_MIN(skb->priority) > 0 &&
TC_H_MIN(skb->priority) <= q->flows_cnt)
return TC_H_MIN(skb->priority);
filter = rcu_dereference_bh(q->filter_list);
if (!filter)
return fq_codel_hash(q, skb) + 1;
*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
result = tcf_classify(skb, filter, &res, false);
if (result >= 0) {
#ifdef CONFIG_NET_CLS_ACT
switch (result) {
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 0;
}
#endif
if (TC_H_MIN(res.classid) <= q->flows_cnt)
return TC_H_MIN(res.classid);
}
return 0;
}
/* helper functions : might be changed when/if skb use a standard list_head */
/* remove one skb from head of slot queue */
static inline struct sk_buff *dequeue_head(struct fq_codel_flow *flow)
{
struct sk_buff *skb = flow->head;
flow->head = skb->next;
skb_mark_not_on_list(skb);
return skb;
}
/* add skb to flow queue (tail add) */
static inline void flow_queue_add(struct fq_codel_flow *flow,
struct sk_buff *skb)
{
if (flow->head == NULL)
flow->head = skb;
else
flow->tail->next = skb;
flow->tail = skb;
skb->next = NULL;
}
static unsigned int fq_codel_drop(struct Qdisc *sch, unsigned int max_packets,
struct sk_buff **to_free)
{
struct fq_codel_sched_data *q = qdisc_priv(sch);
struct sk_buff *skb;
unsigned int maxbacklog = 0, idx = 0, i, len;
struct fq_codel_flow *flow;
unsigned int threshold;
unsigned int mem = 0;
/* Queue is full! Find the fat flow and drop packet(s) from it.
* This might sound expensive, but with 1024 flows, we scan
* 4KB of memory, and we dont need to handle a complex tree
* in fast path (packet queue/enqueue) with many cache misses.
* In stress mode, we'll try to drop 64 packets from the flow,
* amortizing this linear lookup to one cache line per drop.
*/
for (i = 0; i < q->flows_cnt; i++) {
if (q->backlogs[i] > maxbacklog) {
maxbacklog = q->backlogs[i];
idx = i;
}
}
/* Our goal is to drop half of this fat flow backlog */
threshold = maxbacklog >> 1;
flow = &q->flows[idx];
len = 0;
i = 0;
do {
skb = dequeue_head(flow);
len += qdisc_pkt_len(skb);
mem += get_codel_cb(skb)->mem_usage;
__qdisc_drop(skb, to_free);
} while (++i < max_packets && len < threshold);
/* Tell codel to increase its signal strength also */
flow->cvars.count += i;
q->backlogs[idx] -= len;
q->memory_usage -= mem;
sch->qstats.drops += i;
sch->qstats.backlog -= len;
sch->q.qlen -= i;
return idx;
}
static int fq_codel_enqueue(struct sk_buff *skb, struct Qdisc *sch,
struct sk_buff **to_free)
{
struct fq_codel_sched_data *q = qdisc_priv(sch);
unsigned int idx, prev_backlog, prev_qlen;
struct fq_codel_flow *flow;
int ret;
unsigned int pkt_len;
bool memory_limited;
idx = fq_codel_classify(skb, sch, &ret);
if (idx == 0) {
if (ret & __NET_XMIT_BYPASS)
qdisc_qstats_drop(sch);
__qdisc_drop(skb, to_free);
return ret;
}
idx--;
codel_set_enqueue_time(skb);
flow = &q->flows[idx];
flow_queue_add(flow, skb);
q->backlogs[idx] += qdisc_pkt_len(skb);
qdisc_qstats_backlog_inc(sch, skb);
if (list_empty(&flow->flowchain)) {
list_add_tail(&flow->flowchain, &q->new_flows);
q->new_flow_count++;
flow->deficit = q->quantum;
}
get_codel_cb(skb)->mem_usage = skb->truesize;
q->memory_usage += get_codel_cb(skb)->mem_usage;
memory_limited = q->memory_usage > q->memory_limit;
if (++sch->q.qlen <= sch->limit && !memory_limited)
return NET_XMIT_SUCCESS;
prev_backlog = sch->qstats.backlog;
prev_qlen = sch->q.qlen;
/* save this packet length as it might be dropped by fq_codel_drop() */
pkt_len = qdisc_pkt_len(skb);
/* fq_codel_drop() is quite expensive, as it performs a linear search
* in q->backlogs[] to find a fat flow.
* So instead of dropping a single packet, drop half of its backlog
* with a 64 packets limit to not add a too big cpu spike here.
*/
ret = fq_codel_drop(sch, q->drop_batch_size, to_free);
prev_qlen -= sch->q.qlen;
prev_backlog -= sch->qstats.backlog;
q->drop_overlimit += prev_qlen;
if (memory_limited)
q->drop_overmemory += prev_qlen;
/* As we dropped packet(s), better let upper stack know this.
* If we dropped a packet for this flow, return NET_XMIT_CN,
* but in this case, our parents wont increase their backlogs.
*/
if (ret == idx) {
qdisc_tree_reduce_backlog(sch, prev_qlen - 1,
prev_backlog - pkt_len);
return NET_XMIT_CN;
}
qdisc_tree_reduce_backlog(sch, prev_qlen, prev_backlog);
return NET_XMIT_SUCCESS;
}
/* This is the specific function called from codel_dequeue()
* to dequeue a packet from queue. Note: backlog is handled in
* codel, we dont need to reduce it here.
*/
static struct sk_buff *dequeue_func(struct codel_vars *vars, void *ctx)
{
struct Qdisc *sch = ctx;
struct fq_codel_sched_data *q = qdisc_priv(sch);
struct fq_codel_flow *flow;
struct sk_buff *skb = NULL;
flow = container_of(vars, struct fq_codel_flow, cvars);
if (flow->head) {
skb = dequeue_head(flow);
q->backlogs[flow - q->flows] -= qdisc_pkt_len(skb);
q->memory_usage -= get_codel_cb(skb)->mem_usage;
sch->q.qlen--;
sch->qstats.backlog -= qdisc_pkt_len(skb);
}
return skb;
}
static void drop_func(struct sk_buff *skb, void *ctx)
{
struct Qdisc *sch = ctx;
kfree_skb(skb);
qdisc_qstats_drop(sch);
}
static struct sk_buff *fq_codel_dequeue(struct Qdisc *sch)
{
struct fq_codel_sched_data *q = qdisc_priv(sch);
struct sk_buff *skb;
struct fq_codel_flow *flow;
struct list_head *head;
begin:
head = &q->new_flows;
if (list_empty(head)) {
head = &q->old_flows;
if (list_empty(head))
return NULL;
}
flow = list_first_entry(head, struct fq_codel_flow, flowchain);
if (flow->deficit <= 0) {
flow->deficit += q->quantum;
list_move_tail(&flow->flowchain, &q->old_flows);
goto begin;
}
skb = codel_dequeue(sch, &sch->qstats.backlog, &q->cparams,
&flow->cvars, &q->cstats, qdisc_pkt_len,
codel_get_enqueue_time, drop_func, dequeue_func);
if (!skb) {
/* force a pass through old_flows to prevent starvation */
if ((head == &q->new_flows) && !list_empty(&q->old_flows))
list_move_tail(&flow->flowchain, &q->old_flows);
else
list_del_init(&flow->flowchain);
goto begin;
}
qdisc_bstats_update(sch, skb);
flow->deficit -= qdisc_pkt_len(skb);
/* We cant call qdisc_tree_reduce_backlog() if our qlen is 0,
* or HTB crashes. Defer it for next round.
*/
if (q->cstats.drop_count && sch->q.qlen) {
qdisc_tree_reduce_backlog(sch, q->cstats.drop_count,
q->cstats.drop_len);
q->cstats.drop_count = 0;
q->cstats.drop_len = 0;
}
return skb;
}
static void fq_codel_flow_purge(struct fq_codel_flow *flow)
{
rtnl_kfree_skbs(flow->head, flow->tail);
flow->head = NULL;
}
static void fq_codel_reset(struct Qdisc *sch)
{
struct fq_codel_sched_data *q = qdisc_priv(sch);
int i;
INIT_LIST_HEAD(&q->new_flows);
INIT_LIST_HEAD(&q->old_flows);
for (i = 0; i < q->flows_cnt; i++) {
struct fq_codel_flow *flow = q->flows + i;
fq_codel_flow_purge(flow);
INIT_LIST_HEAD(&flow->flowchain);
codel_vars_init(&flow->cvars);
}
memset(q->backlogs, 0, q->flows_cnt * sizeof(u32));
sch->q.qlen = 0;
sch->qstats.backlog = 0;
q->memory_usage = 0;
}
static const struct nla_policy fq_codel_policy[TCA_FQ_CODEL_MAX + 1] = {
[TCA_FQ_CODEL_TARGET] = { .type = NLA_U32 },
[TCA_FQ_CODEL_LIMIT] = { .type = NLA_U32 },
[TCA_FQ_CODEL_INTERVAL] = { .type = NLA_U32 },
[TCA_FQ_CODEL_ECN] = { .type = NLA_U32 },
[TCA_FQ_CODEL_FLOWS] = { .type = NLA_U32 },
[TCA_FQ_CODEL_QUANTUM] = { .type = NLA_U32 },
[TCA_FQ_CODEL_CE_THRESHOLD] = { .type = NLA_U32 },
[TCA_FQ_CODEL_DROP_BATCH_SIZE] = { .type = NLA_U32 },
[TCA_FQ_CODEL_MEMORY_LIMIT] = { .type = NLA_U32 },
};
static int fq_codel_change(struct Qdisc *sch, struct nlattr *opt,
struct netlink_ext_ack *extack)
{
struct fq_codel_sched_data *q = qdisc_priv(sch);
struct nlattr *tb[TCA_FQ_CODEL_MAX + 1];
int err;
if (!opt)
return -EINVAL;
err = nla_parse_nested_deprecated(tb, TCA_FQ_CODEL_MAX, opt,
fq_codel_policy, NULL);
if (err < 0)
return err;
if (tb[TCA_FQ_CODEL_FLOWS]) {
if (q->flows)
return -EINVAL;
q->flows_cnt = nla_get_u32(tb[TCA_FQ_CODEL_FLOWS]);
if (!q->flows_cnt ||
q->flows_cnt > 65536)
return -EINVAL;
}
sch_tree_lock(sch);
if (tb[TCA_FQ_CODEL_TARGET]) {
u64 target = nla_get_u32(tb[TCA_FQ_CODEL_TARGET]);
q->cparams.target = (target * NSEC_PER_USEC) >> CODEL_SHIFT;
}
if (tb[TCA_FQ_CODEL_CE_THRESHOLD]) {
u64 val = nla_get_u32(tb[TCA_FQ_CODEL_CE_THRESHOLD]);
q->cparams.ce_threshold = (val * NSEC_PER_USEC) >> CODEL_SHIFT;
}
if (tb[TCA_FQ_CODEL_INTERVAL]) {
u64 interval = nla_get_u32(tb[TCA_FQ_CODEL_INTERVAL]);
q->cparams.interval = (interval * NSEC_PER_USEC) >> CODEL_SHIFT;
}
if (tb[TCA_FQ_CODEL_LIMIT])
sch->limit = nla_get_u32(tb[TCA_FQ_CODEL_LIMIT]);
if (tb[TCA_FQ_CODEL_ECN])
q->cparams.ecn = !!nla_get_u32(tb[TCA_FQ_CODEL_ECN]);
if (tb[TCA_FQ_CODEL_QUANTUM])
q->quantum = max(256U, nla_get_u32(tb[TCA_FQ_CODEL_QUANTUM]));
if (tb[TCA_FQ_CODEL_DROP_BATCH_SIZE])
q->drop_batch_size = max(1U, nla_get_u32(tb[TCA_FQ_CODEL_DROP_BATCH_SIZE]));
if (tb[TCA_FQ_CODEL_MEMORY_LIMIT])
q->memory_limit = min(1U << 31, nla_get_u32(tb[TCA_FQ_CODEL_MEMORY_LIMIT]));
while (sch->q.qlen > sch->limit ||
q->memory_usage > q->memory_limit) {
struct sk_buff *skb = fq_codel_dequeue(sch);
q->cstats.drop_len += qdisc_pkt_len(skb);
rtnl_kfree_skbs(skb, skb);
q->cstats.drop_count++;
}
qdisc_tree_reduce_backlog(sch, q->cstats.drop_count, q->cstats.drop_len);
q->cstats.drop_count = 0;
q->cstats.drop_len = 0;
sch_tree_unlock(sch);
return 0;
}
static void fq_codel_destroy(struct Qdisc *sch)
{
struct fq_codel_sched_data *q = qdisc_priv(sch);
tcf_block_put(q->block);
kvfree(q->backlogs);
kvfree(q->flows);
}
static int fq_codel_init(struct Qdisc *sch, struct nlattr *opt,
struct netlink_ext_ack *extack)
{
struct fq_codel_sched_data *q = qdisc_priv(sch);
int i;
int err;
sch->limit = 10*1024;
q->flows_cnt = 1024;
q->memory_limit = 32 << 20; /* 32 MBytes */
q->drop_batch_size = 64;
q->quantum = psched_mtu(qdisc_dev(sch));
INIT_LIST_HEAD(&q->new_flows);
INIT_LIST_HEAD(&q->old_flows);
codel_params_init(&q->cparams);
codel_stats_init(&q->cstats);
q->cparams.ecn = true;
q->cparams.mtu = psched_mtu(qdisc_dev(sch));
if (opt) {
err = fq_codel_change(sch, opt, extack);
if (err)
goto init_failure;
}
err = tcf_block_get(&q->block, &q->filter_list, sch, extack);
if (err)
goto init_failure;
if (!q->flows) {
q->flows = kvcalloc(q->flows_cnt,
sizeof(struct fq_codel_flow),
GFP_KERNEL);
if (!q->flows) {
err = -ENOMEM;
goto init_failure;
}
q->backlogs = kvcalloc(q->flows_cnt, sizeof(u32), GFP_KERNEL);
if (!q->backlogs) {
err = -ENOMEM;
goto alloc_failure;
}
for (i = 0; i < q->flows_cnt; i++) {
struct fq_codel_flow *flow = q->flows + i;
INIT_LIST_HEAD(&flow->flowchain);
codel_vars_init(&flow->cvars);
}
}
if (sch->limit >= 1)
sch->flags |= TCQ_F_CAN_BYPASS;
else
sch->flags &= ~TCQ_F_CAN_BYPASS;
return 0;
alloc_failure:
kvfree(q->flows);
q->flows = NULL;
init_failure:
q->flows_cnt = 0;
return err;
}
static int fq_codel_dump(struct Qdisc *sch, struct sk_buff *skb)
{
struct fq_codel_sched_data *q = qdisc_priv(sch);
struct nlattr *opts;
opts = nla_nest_start_noflag(skb, TCA_OPTIONS);
if (opts == NULL)
goto nla_put_failure;
if (nla_put_u32(skb, TCA_FQ_CODEL_TARGET,
codel_time_to_us(q->cparams.target)) ||
nla_put_u32(skb, TCA_FQ_CODEL_LIMIT,
sch->limit) ||
nla_put_u32(skb, TCA_FQ_CODEL_INTERVAL,
codel_time_to_us(q->cparams.interval)) ||
nla_put_u32(skb, TCA_FQ_CODEL_ECN,
q->cparams.ecn) ||
nla_put_u32(skb, TCA_FQ_CODEL_QUANTUM,
q->quantum) ||
nla_put_u32(skb, TCA_FQ_CODEL_DROP_BATCH_SIZE,
q->drop_batch_size) ||
nla_put_u32(skb, TCA_FQ_CODEL_MEMORY_LIMIT,
q->memory_limit) ||
nla_put_u32(skb, TCA_FQ_CODEL_FLOWS,
q->flows_cnt))
goto nla_put_failure;
if (q->cparams.ce_threshold != CODEL_DISABLED_THRESHOLD &&
nla_put_u32(skb, TCA_FQ_CODEL_CE_THRESHOLD,
codel_time_to_us(q->cparams.ce_threshold)))
goto nla_put_failure;
return nla_nest_end(skb, opts);
nla_put_failure:
return -1;
}
static int fq_codel_dump_stats(struct Qdisc *sch, struct gnet_dump *d)
{
struct fq_codel_sched_data *q = qdisc_priv(sch);
struct tc_fq_codel_xstats st = {
.type = TCA_FQ_CODEL_XSTATS_QDISC,
};
struct list_head *pos;
st.qdisc_stats.maxpacket = q->cstats.maxpacket;
st.qdisc_stats.drop_overlimit = q->drop_overlimit;
st.qdisc_stats.ecn_mark = q->cstats.ecn_mark;
st.qdisc_stats.new_flow_count = q->new_flow_count;
st.qdisc_stats.ce_mark = q->cstats.ce_mark;
st.qdisc_stats.memory_usage = q->memory_usage;
st.qdisc_stats.drop_overmemory = q->drop_overmemory;
sch_tree_lock(sch);
list_for_each(pos, &q->new_flows)
st.qdisc_stats.new_flows_len++;
list_for_each(pos, &q->old_flows)
st.qdisc_stats.old_flows_len++;
sch_tree_unlock(sch);
return gnet_stats_copy_app(d, &st, sizeof(st));
}
static struct Qdisc *fq_codel_leaf(struct Qdisc *sch, unsigned long arg)
{
return NULL;
}
static unsigned long fq_codel_find(struct Qdisc *sch, u32 classid)
{
return 0;
}
static unsigned long fq_codel_bind(struct Qdisc *sch, unsigned long parent,
u32 classid)
{
return 0;
}
static void fq_codel_unbind(struct Qdisc *q, unsigned long cl)
{
}
static struct tcf_block *fq_codel_tcf_block(struct Qdisc *sch, unsigned long cl,
struct netlink_ext_ack *extack)
{
struct fq_codel_sched_data *q = qdisc_priv(sch);
if (cl)
return NULL;
return q->block;
}
static int fq_codel_dump_class(struct Qdisc *sch, unsigned long cl,
struct sk_buff *skb, struct tcmsg *tcm)
{
tcm->tcm_handle |= TC_H_MIN(cl);
return 0;
}
static int fq_codel_dump_class_stats(struct Qdisc *sch, unsigned long cl,
struct gnet_dump *d)
{
struct fq_codel_sched_data *q = qdisc_priv(sch);
u32 idx = cl - 1;
struct gnet_stats_queue qs = { 0 };
struct tc_fq_codel_xstats xstats;
if (idx < q->flows_cnt) {
const struct fq_codel_flow *flow = &q->flows[idx];
const struct sk_buff *skb;
memset(&xstats, 0, sizeof(xstats));
xstats.type = TCA_FQ_CODEL_XSTATS_CLASS;
xstats.class_stats.deficit = flow->deficit;
xstats.class_stats.ldelay =
codel_time_to_us(flow->cvars.ldelay);
xstats.class_stats.count = flow->cvars.count;
xstats.class_stats.lastcount = flow->cvars.lastcount;
xstats.class_stats.dropping = flow->cvars.dropping;
if (flow->cvars.dropping) {
codel_tdiff_t delta = flow->cvars.drop_next -
codel_get_time();
xstats.class_stats.drop_next = (delta >= 0) ?
codel_time_to_us(delta) :
-codel_time_to_us(-delta);
}
if (flow->head) {
sch_tree_lock(sch);
skb = flow->head;
while (skb) {
qs.qlen++;
skb = skb->next;
}
sch_tree_unlock(sch);
}
qs.backlog = q->backlogs[idx];
qs.drops = 0;
}
if (gnet_stats_copy_queue(d, NULL, &qs, qs.qlen) < 0)
return -1;
if (idx < q->flows_cnt)
return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
return 0;
}
static void fq_codel_walk(struct Qdisc *sch, struct qdisc_walker *arg)
{
struct fq_codel_sched_data *q = qdisc_priv(sch);
unsigned int i;
if (arg->stop)
return;
for (i = 0; i < q->flows_cnt; i++) {
if (list_empty(&q->flows[i].flowchain) ||
arg->count < arg->skip) {
arg->count++;
continue;
}
if (arg->fn(sch, i + 1, arg) < 0) {
arg->stop = 1;
break;
}
arg->count++;
}
}
static const struct Qdisc_class_ops fq_codel_class_ops = {
.leaf = fq_codel_leaf,
.find = fq_codel_find,
.tcf_block = fq_codel_tcf_block,
.bind_tcf = fq_codel_bind,
.unbind_tcf = fq_codel_unbind,
.dump = fq_codel_dump_class,
.dump_stats = fq_codel_dump_class_stats,
.walk = fq_codel_walk,
};
static struct Qdisc_ops fq_codel_qdisc_ops __read_mostly = {
.cl_ops = &fq_codel_class_ops,
.id = "fq_codel",
.priv_size = sizeof(struct fq_codel_sched_data),
.enqueue = fq_codel_enqueue,
.dequeue = fq_codel_dequeue,
.peek = qdisc_peek_dequeued,
.init = fq_codel_init,
.reset = fq_codel_reset,
.destroy = fq_codel_destroy,
.change = fq_codel_change,
.dump = fq_codel_dump,
.dump_stats = fq_codel_dump_stats,
.owner = THIS_MODULE,
};
static int __init fq_codel_module_init(void)
{
return register_qdisc(&fq_codel_qdisc_ops);
}
static void __exit fq_codel_module_exit(void)
{
unregister_qdisc(&fq_codel_qdisc_ops);
}
module_init(fq_codel_module_init)
module_exit(fq_codel_module_exit)
MODULE_AUTHOR("Eric Dumazet");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Fair Queue CoDel discipline");