![Eric Dumazet](/assets/img/avatar_default.png)
KCSAN reported the following race [1]
BUG: KCSAN: data-race in __dev_queue_xmit / net_tx_action
read to 0xffff8880ba403508 of 1 bytes by task 21814 on cpu 1:
__dev_xmit_skb net/core/dev.c:3389 [inline]
__dev_queue_xmit+0x9db/0x1b40 net/core/dev.c:3761
dev_queue_xmit+0x21/0x30 net/core/dev.c:3825
neigh_hh_output include/net/neighbour.h:500 [inline]
neigh_output include/net/neighbour.h:509 [inline]
ip6_finish_output2+0x873/0xec0 net/ipv6/ip6_output.c:116
__ip6_finish_output net/ipv6/ip6_output.c:142 [inline]
__ip6_finish_output+0x2d7/0x330 net/ipv6/ip6_output.c:127
ip6_finish_output+0x41/0x160 net/ipv6/ip6_output.c:152
NF_HOOK_COND include/linux/netfilter.h:294 [inline]
ip6_output+0xf2/0x280 net/ipv6/ip6_output.c:175
dst_output include/net/dst.h:436 [inline]
ip6_local_out+0x74/0x90 net/ipv6/output_core.c:179
ip6_send_skb+0x53/0x110 net/ipv6/ip6_output.c:1795
udp_v6_send_skb.isra.0+0x3ec/0xa70 net/ipv6/udp.c:1173
udpv6_sendmsg+0x1906/0x1c20 net/ipv6/udp.c:1471
inet6_sendmsg+0x6d/0x90 net/ipv6/af_inet6.c:576
sock_sendmsg_nosec net/socket.c:637 [inline]
sock_sendmsg+0x9f/0xc0 net/socket.c:657
___sys_sendmsg+0x2b7/0x5d0 net/socket.c:2311
__sys_sendmmsg+0x123/0x350 net/socket.c:2413
__do_sys_sendmmsg net/socket.c:2442 [inline]
__se_sys_sendmmsg net/socket.c:2439 [inline]
__x64_sys_sendmmsg+0x64/0x80 net/socket.c:2439
do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x44/0xa9
write to 0xffff8880ba403508 of 1 bytes by interrupt on cpu 0:
qdisc_run_begin include/net/sch_generic.h:160 [inline]
qdisc_run include/net/pkt_sched.h:120 [inline]
net_tx_action+0x2b1/0x6c0 net/core/dev.c:4551
__do_softirq+0x115/0x33f kernel/softirq.c:292
do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082
do_softirq.part.0+0x6b/0x80 kernel/softirq.c:337
do_softirq kernel/softirq.c:329 [inline]
__local_bh_enable_ip+0x76/0x80 kernel/softirq.c:189
local_bh_enable include/linux/bottom_half.h:32 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:688 [inline]
ip6_finish_output2+0x7bb/0xec0 net/ipv6/ip6_output.c:117
__ip6_finish_output net/ipv6/ip6_output.c:142 [inline]
__ip6_finish_output+0x2d7/0x330 net/ipv6/ip6_output.c:127
ip6_finish_output+0x41/0x160 net/ipv6/ip6_output.c:152
NF_HOOK_COND include/linux/netfilter.h:294 [inline]
ip6_output+0xf2/0x280 net/ipv6/ip6_output.c:175
dst_output include/net/dst.h:436 [inline]
ip6_local_out+0x74/0x90 net/ipv6/output_core.c:179
ip6_send_skb+0x53/0x110 net/ipv6/ip6_output.c:1795
udp_v6_send_skb.isra.0+0x3ec/0xa70 net/ipv6/udp.c:1173
udpv6_sendmsg+0x1906/0x1c20 net/ipv6/udp.c:1471
inet6_sendmsg+0x6d/0x90 net/ipv6/af_inet6.c:576
sock_sendmsg_nosec net/socket.c:637 [inline]
sock_sendmsg+0x9f/0xc0 net/socket.c:657
___sys_sendmsg+0x2b7/0x5d0 net/socket.c:2311
__sys_sendmmsg+0x123/0x350 net/socket.c:2413
__do_sys_sendmmsg net/socket.c:2442 [inline]
__se_sys_sendmmsg net/socket.c:2439 [inline]
__x64_sys_sendmmsg+0x64/0x80 net/socket.c:2439
do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 21817 Comm: syz-executor.2 Not tainted 5.4.0-rc6+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Fixes: d518d2ed86
("net/sched: fix race between deactivation and dequeue for NOLOCK qdisc")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1404 lines
33 KiB
C
1404 lines
33 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* net/sched/sch_generic.c Generic packet scheduler routines.
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*
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* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
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* Jamal Hadi Salim, <hadi@cyberus.ca> 990601
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* - Ingress support
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*/
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#include <linux/bitops.h>
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#include <linux/module.h>
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/sched.h>
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#include <linux/string.h>
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#include <linux/errno.h>
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#include <linux/netdevice.h>
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#include <linux/skbuff.h>
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#include <linux/rtnetlink.h>
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#include <linux/init.h>
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#include <linux/rcupdate.h>
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#include <linux/list.h>
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#include <linux/slab.h>
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#include <linux/if_vlan.h>
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#include <linux/skb_array.h>
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#include <linux/if_macvlan.h>
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#include <net/sch_generic.h>
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#include <net/pkt_sched.h>
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#include <net/dst.h>
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#include <trace/events/qdisc.h>
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#include <trace/events/net.h>
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#include <net/xfrm.h>
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/* Qdisc to use by default */
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const struct Qdisc_ops *default_qdisc_ops = &pfifo_fast_ops;
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EXPORT_SYMBOL(default_qdisc_ops);
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/* Main transmission queue. */
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/* Modifications to data participating in scheduling must be protected with
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* qdisc_lock(qdisc) spinlock.
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*
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* The idea is the following:
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* - enqueue, dequeue are serialized via qdisc root lock
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* - ingress filtering is also serialized via qdisc root lock
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* - updates to tree and tree walking are only done under the rtnl mutex.
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*/
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#define SKB_XOFF_MAGIC ((struct sk_buff *)1UL)
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static inline struct sk_buff *__skb_dequeue_bad_txq(struct Qdisc *q)
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{
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const struct netdev_queue *txq = q->dev_queue;
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spinlock_t *lock = NULL;
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struct sk_buff *skb;
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if (q->flags & TCQ_F_NOLOCK) {
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lock = qdisc_lock(q);
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spin_lock(lock);
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}
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skb = skb_peek(&q->skb_bad_txq);
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if (skb) {
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/* check the reason of requeuing without tx lock first */
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txq = skb_get_tx_queue(txq->dev, skb);
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if (!netif_xmit_frozen_or_stopped(txq)) {
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skb = __skb_dequeue(&q->skb_bad_txq);
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if (qdisc_is_percpu_stats(q)) {
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qdisc_qstats_cpu_backlog_dec(q, skb);
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qdisc_qstats_cpu_qlen_dec(q);
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} else {
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qdisc_qstats_backlog_dec(q, skb);
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q->q.qlen--;
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}
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} else {
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skb = SKB_XOFF_MAGIC;
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}
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}
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if (lock)
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spin_unlock(lock);
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return skb;
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}
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static inline struct sk_buff *qdisc_dequeue_skb_bad_txq(struct Qdisc *q)
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{
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struct sk_buff *skb = skb_peek(&q->skb_bad_txq);
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if (unlikely(skb))
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skb = __skb_dequeue_bad_txq(q);
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return skb;
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}
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static inline void qdisc_enqueue_skb_bad_txq(struct Qdisc *q,
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struct sk_buff *skb)
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{
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spinlock_t *lock = NULL;
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if (q->flags & TCQ_F_NOLOCK) {
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lock = qdisc_lock(q);
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spin_lock(lock);
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}
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__skb_queue_tail(&q->skb_bad_txq, skb);
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if (qdisc_is_percpu_stats(q)) {
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qdisc_qstats_cpu_backlog_inc(q, skb);
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qdisc_qstats_cpu_qlen_inc(q);
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} else {
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qdisc_qstats_backlog_inc(q, skb);
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q->q.qlen++;
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}
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if (lock)
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spin_unlock(lock);
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}
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static inline void dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q)
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{
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spinlock_t *lock = NULL;
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if (q->flags & TCQ_F_NOLOCK) {
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lock = qdisc_lock(q);
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spin_lock(lock);
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}
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while (skb) {
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struct sk_buff *next = skb->next;
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__skb_queue_tail(&q->gso_skb, skb);
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/* it's still part of the queue */
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if (qdisc_is_percpu_stats(q)) {
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qdisc_qstats_cpu_requeues_inc(q);
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qdisc_qstats_cpu_backlog_inc(q, skb);
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qdisc_qstats_cpu_qlen_inc(q);
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} else {
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q->qstats.requeues++;
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qdisc_qstats_backlog_inc(q, skb);
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q->q.qlen++;
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}
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skb = next;
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}
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if (lock)
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spin_unlock(lock);
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__netif_schedule(q);
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}
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static void try_bulk_dequeue_skb(struct Qdisc *q,
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struct sk_buff *skb,
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const struct netdev_queue *txq,
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int *packets)
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{
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int bytelimit = qdisc_avail_bulklimit(txq) - skb->len;
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while (bytelimit > 0) {
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struct sk_buff *nskb = q->dequeue(q);
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if (!nskb)
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break;
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bytelimit -= nskb->len; /* covers GSO len */
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skb->next = nskb;
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skb = nskb;
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(*packets)++; /* GSO counts as one pkt */
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}
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skb_mark_not_on_list(skb);
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}
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/* This variant of try_bulk_dequeue_skb() makes sure
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* all skbs in the chain are for the same txq
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*/
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static void try_bulk_dequeue_skb_slow(struct Qdisc *q,
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struct sk_buff *skb,
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int *packets)
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{
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int mapping = skb_get_queue_mapping(skb);
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struct sk_buff *nskb;
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int cnt = 0;
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do {
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nskb = q->dequeue(q);
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if (!nskb)
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break;
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if (unlikely(skb_get_queue_mapping(nskb) != mapping)) {
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qdisc_enqueue_skb_bad_txq(q, nskb);
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break;
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}
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skb->next = nskb;
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skb = nskb;
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} while (++cnt < 8);
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(*packets) += cnt;
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skb_mark_not_on_list(skb);
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}
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/* Note that dequeue_skb can possibly return a SKB list (via skb->next).
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* A requeued skb (via q->gso_skb) can also be a SKB list.
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*/
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static struct sk_buff *dequeue_skb(struct Qdisc *q, bool *validate,
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int *packets)
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{
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const struct netdev_queue *txq = q->dev_queue;
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struct sk_buff *skb = NULL;
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*packets = 1;
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if (unlikely(!skb_queue_empty(&q->gso_skb))) {
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spinlock_t *lock = NULL;
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if (q->flags & TCQ_F_NOLOCK) {
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lock = qdisc_lock(q);
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spin_lock(lock);
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}
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skb = skb_peek(&q->gso_skb);
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/* skb may be null if another cpu pulls gso_skb off in between
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* empty check and lock.
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*/
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if (!skb) {
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if (lock)
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spin_unlock(lock);
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goto validate;
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}
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/* skb in gso_skb were already validated */
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*validate = false;
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if (xfrm_offload(skb))
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*validate = true;
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/* check the reason of requeuing without tx lock first */
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txq = skb_get_tx_queue(txq->dev, skb);
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if (!netif_xmit_frozen_or_stopped(txq)) {
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skb = __skb_dequeue(&q->gso_skb);
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if (qdisc_is_percpu_stats(q)) {
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qdisc_qstats_cpu_backlog_dec(q, skb);
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qdisc_qstats_cpu_qlen_dec(q);
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} else {
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qdisc_qstats_backlog_dec(q, skb);
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q->q.qlen--;
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}
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} else {
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skb = NULL;
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}
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if (lock)
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spin_unlock(lock);
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goto trace;
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}
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validate:
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*validate = true;
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if ((q->flags & TCQ_F_ONETXQUEUE) &&
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netif_xmit_frozen_or_stopped(txq))
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return skb;
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skb = qdisc_dequeue_skb_bad_txq(q);
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if (unlikely(skb)) {
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if (skb == SKB_XOFF_MAGIC)
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return NULL;
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goto bulk;
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}
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skb = q->dequeue(q);
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if (skb) {
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bulk:
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if (qdisc_may_bulk(q))
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try_bulk_dequeue_skb(q, skb, txq, packets);
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else
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try_bulk_dequeue_skb_slow(q, skb, packets);
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}
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trace:
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trace_qdisc_dequeue(q, txq, *packets, skb);
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return skb;
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}
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/*
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* Transmit possibly several skbs, and handle the return status as
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* required. Owning running seqcount bit guarantees that
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* only one CPU can execute this function.
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*
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* Returns to the caller:
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* false - hardware queue frozen backoff
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* true - feel free to send more pkts
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*/
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bool sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
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struct net_device *dev, struct netdev_queue *txq,
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spinlock_t *root_lock, bool validate)
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{
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int ret = NETDEV_TX_BUSY;
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bool again = false;
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/* And release qdisc */
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if (root_lock)
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spin_unlock(root_lock);
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/* Note that we validate skb (GSO, checksum, ...) outside of locks */
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if (validate)
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skb = validate_xmit_skb_list(skb, dev, &again);
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#ifdef CONFIG_XFRM_OFFLOAD
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if (unlikely(again)) {
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if (root_lock)
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spin_lock(root_lock);
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dev_requeue_skb(skb, q);
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return false;
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}
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#endif
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if (likely(skb)) {
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HARD_TX_LOCK(dev, txq, smp_processor_id());
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if (!netif_xmit_frozen_or_stopped(txq))
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skb = dev_hard_start_xmit(skb, dev, txq, &ret);
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HARD_TX_UNLOCK(dev, txq);
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} else {
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if (root_lock)
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spin_lock(root_lock);
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return true;
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}
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if (root_lock)
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spin_lock(root_lock);
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if (!dev_xmit_complete(ret)) {
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/* Driver returned NETDEV_TX_BUSY - requeue skb */
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if (unlikely(ret != NETDEV_TX_BUSY))
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net_warn_ratelimited("BUG %s code %d qlen %d\n",
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dev->name, ret, q->q.qlen);
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dev_requeue_skb(skb, q);
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return false;
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}
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return true;
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}
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/*
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* NOTE: Called under qdisc_lock(q) with locally disabled BH.
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*
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* running seqcount guarantees only one CPU can process
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* this qdisc at a time. qdisc_lock(q) serializes queue accesses for
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* this queue.
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*
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* netif_tx_lock serializes accesses to device driver.
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*
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* qdisc_lock(q) and netif_tx_lock are mutually exclusive,
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* if one is grabbed, another must be free.
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*
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* Note, that this procedure can be called by a watchdog timer
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*
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* Returns to the caller:
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* 0 - queue is empty or throttled.
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* >0 - queue is not empty.
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*
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*/
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static inline bool qdisc_restart(struct Qdisc *q, int *packets)
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{
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spinlock_t *root_lock = NULL;
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struct netdev_queue *txq;
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struct net_device *dev;
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struct sk_buff *skb;
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bool validate;
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/* Dequeue packet */
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skb = dequeue_skb(q, &validate, packets);
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if (unlikely(!skb))
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return false;
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if (!(q->flags & TCQ_F_NOLOCK))
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root_lock = qdisc_lock(q);
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dev = qdisc_dev(q);
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txq = skb_get_tx_queue(dev, skb);
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return sch_direct_xmit(skb, q, dev, txq, root_lock, validate);
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}
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void __qdisc_run(struct Qdisc *q)
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{
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int quota = dev_tx_weight;
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int packets;
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while (qdisc_restart(q, &packets)) {
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quota -= packets;
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if (quota <= 0) {
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__netif_schedule(q);
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break;
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}
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}
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}
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unsigned long dev_trans_start(struct net_device *dev)
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{
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unsigned long val, res;
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unsigned int i;
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if (is_vlan_dev(dev))
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dev = vlan_dev_real_dev(dev);
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else if (netif_is_macvlan(dev))
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dev = macvlan_dev_real_dev(dev);
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res = netdev_get_tx_queue(dev, 0)->trans_start;
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for (i = 1; i < dev->num_tx_queues; i++) {
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val = netdev_get_tx_queue(dev, i)->trans_start;
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if (val && time_after(val, res))
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res = val;
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}
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return res;
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}
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EXPORT_SYMBOL(dev_trans_start);
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|
static void dev_watchdog(struct timer_list *t)
|
|
{
|
|
struct net_device *dev = from_timer(dev, t, watchdog_timer);
|
|
|
|
netif_tx_lock(dev);
|
|
if (!qdisc_tx_is_noop(dev)) {
|
|
if (netif_device_present(dev) &&
|
|
netif_running(dev) &&
|
|
netif_carrier_ok(dev)) {
|
|
int some_queue_timedout = 0;
|
|
unsigned int i;
|
|
unsigned long trans_start;
|
|
|
|
for (i = 0; i < dev->num_tx_queues; i++) {
|
|
struct netdev_queue *txq;
|
|
|
|
txq = netdev_get_tx_queue(dev, i);
|
|
trans_start = txq->trans_start;
|
|
if (netif_xmit_stopped(txq) &&
|
|
time_after(jiffies, (trans_start +
|
|
dev->watchdog_timeo))) {
|
|
some_queue_timedout = 1;
|
|
txq->trans_timeout++;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (some_queue_timedout) {
|
|
trace_net_dev_xmit_timeout(dev, i);
|
|
WARN_ONCE(1, KERN_INFO "NETDEV WATCHDOG: %s (%s): transmit queue %u timed out\n",
|
|
dev->name, netdev_drivername(dev), i);
|
|
dev->netdev_ops->ndo_tx_timeout(dev);
|
|
}
|
|
if (!mod_timer(&dev->watchdog_timer,
|
|
round_jiffies(jiffies +
|
|
dev->watchdog_timeo)))
|
|
dev_hold(dev);
|
|
}
|
|
}
|
|
netif_tx_unlock(dev);
|
|
|
|
dev_put(dev);
|
|
}
|
|
|
|
void __netdev_watchdog_up(struct net_device *dev)
|
|
{
|
|
if (dev->netdev_ops->ndo_tx_timeout) {
|
|
if (dev->watchdog_timeo <= 0)
|
|
dev->watchdog_timeo = 5*HZ;
|
|
if (!mod_timer(&dev->watchdog_timer,
|
|
round_jiffies(jiffies + dev->watchdog_timeo)))
|
|
dev_hold(dev);
|
|
}
|
|
}
|
|
|
|
static void dev_watchdog_up(struct net_device *dev)
|
|
{
|
|
__netdev_watchdog_up(dev);
|
|
}
|
|
|
|
static void dev_watchdog_down(struct net_device *dev)
|
|
{
|
|
netif_tx_lock_bh(dev);
|
|
if (del_timer(&dev->watchdog_timer))
|
|
dev_put(dev);
|
|
netif_tx_unlock_bh(dev);
|
|
}
|
|
|
|
/**
|
|
* netif_carrier_on - set carrier
|
|
* @dev: network device
|
|
*
|
|
* Device has detected acquisition of carrier.
|
|
*/
|
|
void netif_carrier_on(struct net_device *dev)
|
|
{
|
|
if (test_and_clear_bit(__LINK_STATE_NOCARRIER, &dev->state)) {
|
|
if (dev->reg_state == NETREG_UNINITIALIZED)
|
|
return;
|
|
atomic_inc(&dev->carrier_up_count);
|
|
linkwatch_fire_event(dev);
|
|
if (netif_running(dev))
|
|
__netdev_watchdog_up(dev);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(netif_carrier_on);
|
|
|
|
/**
|
|
* netif_carrier_off - clear carrier
|
|
* @dev: network device
|
|
*
|
|
* Device has detected loss of carrier.
|
|
*/
|
|
void netif_carrier_off(struct net_device *dev)
|
|
{
|
|
if (!test_and_set_bit(__LINK_STATE_NOCARRIER, &dev->state)) {
|
|
if (dev->reg_state == NETREG_UNINITIALIZED)
|
|
return;
|
|
atomic_inc(&dev->carrier_down_count);
|
|
linkwatch_fire_event(dev);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(netif_carrier_off);
|
|
|
|
/* "NOOP" scheduler: the best scheduler, recommended for all interfaces
|
|
under all circumstances. It is difficult to invent anything faster or
|
|
cheaper.
|
|
*/
|
|
|
|
static int noop_enqueue(struct sk_buff *skb, struct Qdisc *qdisc,
|
|
struct sk_buff **to_free)
|
|
{
|
|
__qdisc_drop(skb, to_free);
|
|
return NET_XMIT_CN;
|
|
}
|
|
|
|
static struct sk_buff *noop_dequeue(struct Qdisc *qdisc)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
struct Qdisc_ops noop_qdisc_ops __read_mostly = {
|
|
.id = "noop",
|
|
.priv_size = 0,
|
|
.enqueue = noop_enqueue,
|
|
.dequeue = noop_dequeue,
|
|
.peek = noop_dequeue,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static struct netdev_queue noop_netdev_queue = {
|
|
RCU_POINTER_INITIALIZER(qdisc, &noop_qdisc),
|
|
.qdisc_sleeping = &noop_qdisc,
|
|
};
|
|
|
|
struct Qdisc noop_qdisc = {
|
|
.enqueue = noop_enqueue,
|
|
.dequeue = noop_dequeue,
|
|
.flags = TCQ_F_BUILTIN,
|
|
.ops = &noop_qdisc_ops,
|
|
.q.lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.q.lock),
|
|
.dev_queue = &noop_netdev_queue,
|
|
.running = SEQCNT_ZERO(noop_qdisc.running),
|
|
.busylock = __SPIN_LOCK_UNLOCKED(noop_qdisc.busylock),
|
|
.gso_skb = {
|
|
.next = (struct sk_buff *)&noop_qdisc.gso_skb,
|
|
.prev = (struct sk_buff *)&noop_qdisc.gso_skb,
|
|
.qlen = 0,
|
|
.lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.gso_skb.lock),
|
|
},
|
|
.skb_bad_txq = {
|
|
.next = (struct sk_buff *)&noop_qdisc.skb_bad_txq,
|
|
.prev = (struct sk_buff *)&noop_qdisc.skb_bad_txq,
|
|
.qlen = 0,
|
|
.lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.skb_bad_txq.lock),
|
|
},
|
|
};
|
|
EXPORT_SYMBOL(noop_qdisc);
|
|
|
|
static int noqueue_init(struct Qdisc *qdisc, struct nlattr *opt,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
/* register_qdisc() assigns a default of noop_enqueue if unset,
|
|
* but __dev_queue_xmit() treats noqueue only as such
|
|
* if this is NULL - so clear it here. */
|
|
qdisc->enqueue = NULL;
|
|
return 0;
|
|
}
|
|
|
|
struct Qdisc_ops noqueue_qdisc_ops __read_mostly = {
|
|
.id = "noqueue",
|
|
.priv_size = 0,
|
|
.init = noqueue_init,
|
|
.enqueue = noop_enqueue,
|
|
.dequeue = noop_dequeue,
|
|
.peek = noop_dequeue,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static const u8 prio2band[TC_PRIO_MAX + 1] = {
|
|
1, 2, 2, 2, 1, 2, 0, 0 , 1, 1, 1, 1, 1, 1, 1, 1
|
|
};
|
|
|
|
/* 3-band FIFO queue: old style, but should be a bit faster than
|
|
generic prio+fifo combination.
|
|
*/
|
|
|
|
#define PFIFO_FAST_BANDS 3
|
|
|
|
/*
|
|
* Private data for a pfifo_fast scheduler containing:
|
|
* - rings for priority bands
|
|
*/
|
|
struct pfifo_fast_priv {
|
|
struct skb_array q[PFIFO_FAST_BANDS];
|
|
};
|
|
|
|
static inline struct skb_array *band2list(struct pfifo_fast_priv *priv,
|
|
int band)
|
|
{
|
|
return &priv->q[band];
|
|
}
|
|
|
|
static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc *qdisc,
|
|
struct sk_buff **to_free)
|
|
{
|
|
int band = prio2band[skb->priority & TC_PRIO_MAX];
|
|
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
|
|
struct skb_array *q = band2list(priv, band);
|
|
unsigned int pkt_len = qdisc_pkt_len(skb);
|
|
int err;
|
|
|
|
err = skb_array_produce(q, skb);
|
|
|
|
if (unlikely(err)) {
|
|
if (qdisc_is_percpu_stats(qdisc))
|
|
return qdisc_drop_cpu(skb, qdisc, to_free);
|
|
else
|
|
return qdisc_drop(skb, qdisc, to_free);
|
|
}
|
|
|
|
qdisc_update_stats_at_enqueue(qdisc, pkt_len);
|
|
return NET_XMIT_SUCCESS;
|
|
}
|
|
|
|
static struct sk_buff *pfifo_fast_dequeue(struct Qdisc *qdisc)
|
|
{
|
|
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
|
|
struct sk_buff *skb = NULL;
|
|
int band;
|
|
|
|
for (band = 0; band < PFIFO_FAST_BANDS && !skb; band++) {
|
|
struct skb_array *q = band2list(priv, band);
|
|
|
|
if (__skb_array_empty(q))
|
|
continue;
|
|
|
|
skb = __skb_array_consume(q);
|
|
}
|
|
if (likely(skb)) {
|
|
qdisc_update_stats_at_dequeue(qdisc, skb);
|
|
} else {
|
|
WRITE_ONCE(qdisc->empty, true);
|
|
}
|
|
|
|
return skb;
|
|
}
|
|
|
|
static struct sk_buff *pfifo_fast_peek(struct Qdisc *qdisc)
|
|
{
|
|
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
|
|
struct sk_buff *skb = NULL;
|
|
int band;
|
|
|
|
for (band = 0; band < PFIFO_FAST_BANDS && !skb; band++) {
|
|
struct skb_array *q = band2list(priv, band);
|
|
|
|
skb = __skb_array_peek(q);
|
|
}
|
|
|
|
return skb;
|
|
}
|
|
|
|
static void pfifo_fast_reset(struct Qdisc *qdisc)
|
|
{
|
|
int i, band;
|
|
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
|
|
|
|
for (band = 0; band < PFIFO_FAST_BANDS; band++) {
|
|
struct skb_array *q = band2list(priv, band);
|
|
struct sk_buff *skb;
|
|
|
|
/* NULL ring is possible if destroy path is due to a failed
|
|
* skb_array_init() in pfifo_fast_init() case.
|
|
*/
|
|
if (!q->ring.queue)
|
|
continue;
|
|
|
|
while ((skb = __skb_array_consume(q)) != NULL)
|
|
kfree_skb(skb);
|
|
}
|
|
|
|
if (qdisc_is_percpu_stats(qdisc)) {
|
|
for_each_possible_cpu(i) {
|
|
struct gnet_stats_queue *q;
|
|
|
|
q = per_cpu_ptr(qdisc->cpu_qstats, i);
|
|
q->backlog = 0;
|
|
q->qlen = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
static int pfifo_fast_dump(struct Qdisc *qdisc, struct sk_buff *skb)
|
|
{
|
|
struct tc_prio_qopt opt = { .bands = PFIFO_FAST_BANDS };
|
|
|
|
memcpy(&opt.priomap, prio2band, TC_PRIO_MAX + 1);
|
|
if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt))
|
|
goto nla_put_failure;
|
|
return skb->len;
|
|
|
|
nla_put_failure:
|
|
return -1;
|
|
}
|
|
|
|
static int pfifo_fast_init(struct Qdisc *qdisc, struct nlattr *opt,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
unsigned int qlen = qdisc_dev(qdisc)->tx_queue_len;
|
|
struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
|
|
int prio;
|
|
|
|
/* guard against zero length rings */
|
|
if (!qlen)
|
|
return -EINVAL;
|
|
|
|
for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) {
|
|
struct skb_array *q = band2list(priv, prio);
|
|
int err;
|
|
|
|
err = skb_array_init(q, qlen, GFP_KERNEL);
|
|
if (err)
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* Can by-pass the queue discipline */
|
|
qdisc->flags |= TCQ_F_CAN_BYPASS;
|
|
return 0;
|
|
}
|
|
|
|
static void pfifo_fast_destroy(struct Qdisc *sch)
|
|
{
|
|
struct pfifo_fast_priv *priv = qdisc_priv(sch);
|
|
int prio;
|
|
|
|
for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) {
|
|
struct skb_array *q = band2list(priv, prio);
|
|
|
|
/* NULL ring is possible if destroy path is due to a failed
|
|
* skb_array_init() in pfifo_fast_init() case.
|
|
*/
|
|
if (!q->ring.queue)
|
|
continue;
|
|
/* Destroy ring but no need to kfree_skb because a call to
|
|
* pfifo_fast_reset() has already done that work.
|
|
*/
|
|
ptr_ring_cleanup(&q->ring, NULL);
|
|
}
|
|
}
|
|
|
|
static int pfifo_fast_change_tx_queue_len(struct Qdisc *sch,
|
|
unsigned int new_len)
|
|
{
|
|
struct pfifo_fast_priv *priv = qdisc_priv(sch);
|
|
struct skb_array *bands[PFIFO_FAST_BANDS];
|
|
int prio;
|
|
|
|
for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) {
|
|
struct skb_array *q = band2list(priv, prio);
|
|
|
|
bands[prio] = q;
|
|
}
|
|
|
|
return skb_array_resize_multiple(bands, PFIFO_FAST_BANDS, new_len,
|
|
GFP_KERNEL);
|
|
}
|
|
|
|
struct Qdisc_ops pfifo_fast_ops __read_mostly = {
|
|
.id = "pfifo_fast",
|
|
.priv_size = sizeof(struct pfifo_fast_priv),
|
|
.enqueue = pfifo_fast_enqueue,
|
|
.dequeue = pfifo_fast_dequeue,
|
|
.peek = pfifo_fast_peek,
|
|
.init = pfifo_fast_init,
|
|
.destroy = pfifo_fast_destroy,
|
|
.reset = pfifo_fast_reset,
|
|
.dump = pfifo_fast_dump,
|
|
.change_tx_queue_len = pfifo_fast_change_tx_queue_len,
|
|
.owner = THIS_MODULE,
|
|
.static_flags = TCQ_F_NOLOCK | TCQ_F_CPUSTATS,
|
|
};
|
|
EXPORT_SYMBOL(pfifo_fast_ops);
|
|
|
|
struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
|
|
const struct Qdisc_ops *ops,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
void *p;
|
|
struct Qdisc *sch;
|
|
unsigned int size = QDISC_ALIGN(sizeof(*sch)) + ops->priv_size;
|
|
int err = -ENOBUFS;
|
|
struct net_device *dev;
|
|
|
|
if (!dev_queue) {
|
|
NL_SET_ERR_MSG(extack, "No device queue given");
|
|
err = -EINVAL;
|
|
goto errout;
|
|
}
|
|
|
|
dev = dev_queue->dev;
|
|
p = kzalloc_node(size, GFP_KERNEL,
|
|
netdev_queue_numa_node_read(dev_queue));
|
|
|
|
if (!p)
|
|
goto errout;
|
|
sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p);
|
|
/* if we got non aligned memory, ask more and do alignment ourself */
|
|
if (sch != p) {
|
|
kfree(p);
|
|
p = kzalloc_node(size + QDISC_ALIGNTO - 1, GFP_KERNEL,
|
|
netdev_queue_numa_node_read(dev_queue));
|
|
if (!p)
|
|
goto errout;
|
|
sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p);
|
|
sch->padded = (char *) sch - (char *) p;
|
|
}
|
|
__skb_queue_head_init(&sch->gso_skb);
|
|
__skb_queue_head_init(&sch->skb_bad_txq);
|
|
qdisc_skb_head_init(&sch->q);
|
|
spin_lock_init(&sch->q.lock);
|
|
|
|
if (ops->static_flags & TCQ_F_CPUSTATS) {
|
|
sch->cpu_bstats =
|
|
netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
|
|
if (!sch->cpu_bstats)
|
|
goto errout1;
|
|
|
|
sch->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
|
|
if (!sch->cpu_qstats) {
|
|
free_percpu(sch->cpu_bstats);
|
|
goto errout1;
|
|
}
|
|
}
|
|
|
|
spin_lock_init(&sch->busylock);
|
|
/* seqlock has the same scope of busylock, for NOLOCK qdisc */
|
|
spin_lock_init(&sch->seqlock);
|
|
seqcount_init(&sch->running);
|
|
|
|
sch->ops = ops;
|
|
sch->flags = ops->static_flags;
|
|
sch->enqueue = ops->enqueue;
|
|
sch->dequeue = ops->dequeue;
|
|
sch->dev_queue = dev_queue;
|
|
sch->empty = true;
|
|
dev_hold(dev);
|
|
refcount_set(&sch->refcnt, 1);
|
|
|
|
if (sch != &noop_qdisc) {
|
|
lockdep_set_class(&sch->busylock, &dev->qdisc_tx_busylock_key);
|
|
lockdep_set_class(&sch->seqlock, &dev->qdisc_tx_busylock_key);
|
|
lockdep_set_class(&sch->running, &dev->qdisc_running_key);
|
|
}
|
|
|
|
return sch;
|
|
errout1:
|
|
kfree(p);
|
|
errout:
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
|
|
const struct Qdisc_ops *ops,
|
|
unsigned int parentid,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
struct Qdisc *sch;
|
|
|
|
if (!try_module_get(ops->owner)) {
|
|
NL_SET_ERR_MSG(extack, "Failed to increase module reference counter");
|
|
return NULL;
|
|
}
|
|
|
|
sch = qdisc_alloc(dev_queue, ops, extack);
|
|
if (IS_ERR(sch)) {
|
|
module_put(ops->owner);
|
|
return NULL;
|
|
}
|
|
sch->parent = parentid;
|
|
|
|
if (!ops->init || ops->init(sch, NULL, extack) == 0)
|
|
return sch;
|
|
|
|
qdisc_put(sch);
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL(qdisc_create_dflt);
|
|
|
|
/* Under qdisc_lock(qdisc) and BH! */
|
|
|
|
void qdisc_reset(struct Qdisc *qdisc)
|
|
{
|
|
const struct Qdisc_ops *ops = qdisc->ops;
|
|
struct sk_buff *skb, *tmp;
|
|
|
|
if (ops->reset)
|
|
ops->reset(qdisc);
|
|
|
|
skb_queue_walk_safe(&qdisc->gso_skb, skb, tmp) {
|
|
__skb_unlink(skb, &qdisc->gso_skb);
|
|
kfree_skb_list(skb);
|
|
}
|
|
|
|
skb_queue_walk_safe(&qdisc->skb_bad_txq, skb, tmp) {
|
|
__skb_unlink(skb, &qdisc->skb_bad_txq);
|
|
kfree_skb_list(skb);
|
|
}
|
|
|
|
qdisc->q.qlen = 0;
|
|
qdisc->qstats.backlog = 0;
|
|
}
|
|
EXPORT_SYMBOL(qdisc_reset);
|
|
|
|
void qdisc_free(struct Qdisc *qdisc)
|
|
{
|
|
if (qdisc_is_percpu_stats(qdisc)) {
|
|
free_percpu(qdisc->cpu_bstats);
|
|
free_percpu(qdisc->cpu_qstats);
|
|
}
|
|
|
|
kfree((char *) qdisc - qdisc->padded);
|
|
}
|
|
|
|
static void qdisc_free_cb(struct rcu_head *head)
|
|
{
|
|
struct Qdisc *q = container_of(head, struct Qdisc, rcu);
|
|
|
|
qdisc_free(q);
|
|
}
|
|
|
|
static void qdisc_destroy(struct Qdisc *qdisc)
|
|
{
|
|
const struct Qdisc_ops *ops = qdisc->ops;
|
|
struct sk_buff *skb, *tmp;
|
|
|
|
#ifdef CONFIG_NET_SCHED
|
|
qdisc_hash_del(qdisc);
|
|
|
|
qdisc_put_stab(rtnl_dereference(qdisc->stab));
|
|
#endif
|
|
gen_kill_estimator(&qdisc->rate_est);
|
|
if (ops->reset)
|
|
ops->reset(qdisc);
|
|
if (ops->destroy)
|
|
ops->destroy(qdisc);
|
|
|
|
module_put(ops->owner);
|
|
dev_put(qdisc_dev(qdisc));
|
|
|
|
skb_queue_walk_safe(&qdisc->gso_skb, skb, tmp) {
|
|
__skb_unlink(skb, &qdisc->gso_skb);
|
|
kfree_skb_list(skb);
|
|
}
|
|
|
|
skb_queue_walk_safe(&qdisc->skb_bad_txq, skb, tmp) {
|
|
__skb_unlink(skb, &qdisc->skb_bad_txq);
|
|
kfree_skb_list(skb);
|
|
}
|
|
|
|
call_rcu(&qdisc->rcu, qdisc_free_cb);
|
|
}
|
|
|
|
void qdisc_put(struct Qdisc *qdisc)
|
|
{
|
|
if (!qdisc)
|
|
return;
|
|
|
|
if (qdisc->flags & TCQ_F_BUILTIN ||
|
|
!refcount_dec_and_test(&qdisc->refcnt))
|
|
return;
|
|
|
|
qdisc_destroy(qdisc);
|
|
}
|
|
EXPORT_SYMBOL(qdisc_put);
|
|
|
|
/* Version of qdisc_put() that is called with rtnl mutex unlocked.
|
|
* Intended to be used as optimization, this function only takes rtnl lock if
|
|
* qdisc reference counter reached zero.
|
|
*/
|
|
|
|
void qdisc_put_unlocked(struct Qdisc *qdisc)
|
|
{
|
|
if (qdisc->flags & TCQ_F_BUILTIN ||
|
|
!refcount_dec_and_rtnl_lock(&qdisc->refcnt))
|
|
return;
|
|
|
|
qdisc_destroy(qdisc);
|
|
rtnl_unlock();
|
|
}
|
|
EXPORT_SYMBOL(qdisc_put_unlocked);
|
|
|
|
/* Attach toplevel qdisc to device queue. */
|
|
struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
|
|
struct Qdisc *qdisc)
|
|
{
|
|
struct Qdisc *oqdisc = dev_queue->qdisc_sleeping;
|
|
spinlock_t *root_lock;
|
|
|
|
root_lock = qdisc_lock(oqdisc);
|
|
spin_lock_bh(root_lock);
|
|
|
|
/* ... and graft new one */
|
|
if (qdisc == NULL)
|
|
qdisc = &noop_qdisc;
|
|
dev_queue->qdisc_sleeping = qdisc;
|
|
rcu_assign_pointer(dev_queue->qdisc, &noop_qdisc);
|
|
|
|
spin_unlock_bh(root_lock);
|
|
|
|
return oqdisc;
|
|
}
|
|
EXPORT_SYMBOL(dev_graft_qdisc);
|
|
|
|
static void attach_one_default_qdisc(struct net_device *dev,
|
|
struct netdev_queue *dev_queue,
|
|
void *_unused)
|
|
{
|
|
struct Qdisc *qdisc;
|
|
const struct Qdisc_ops *ops = default_qdisc_ops;
|
|
|
|
if (dev->priv_flags & IFF_NO_QUEUE)
|
|
ops = &noqueue_qdisc_ops;
|
|
else if(dev->type == ARPHRD_CAN)
|
|
ops = &pfifo_fast_ops;
|
|
|
|
qdisc = qdisc_create_dflt(dev_queue, ops, TC_H_ROOT, NULL);
|
|
if (!qdisc) {
|
|
netdev_info(dev, "activation failed\n");
|
|
return;
|
|
}
|
|
if (!netif_is_multiqueue(dev))
|
|
qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
|
|
dev_queue->qdisc_sleeping = qdisc;
|
|
}
|
|
|
|
static void attach_default_qdiscs(struct net_device *dev)
|
|
{
|
|
struct netdev_queue *txq;
|
|
struct Qdisc *qdisc;
|
|
|
|
txq = netdev_get_tx_queue(dev, 0);
|
|
|
|
if (!netif_is_multiqueue(dev) ||
|
|
dev->priv_flags & IFF_NO_QUEUE) {
|
|
netdev_for_each_tx_queue(dev, attach_one_default_qdisc, NULL);
|
|
dev->qdisc = txq->qdisc_sleeping;
|
|
qdisc_refcount_inc(dev->qdisc);
|
|
} else {
|
|
qdisc = qdisc_create_dflt(txq, &mq_qdisc_ops, TC_H_ROOT, NULL);
|
|
if (qdisc) {
|
|
dev->qdisc = qdisc;
|
|
qdisc->ops->attach(qdisc);
|
|
}
|
|
}
|
|
#ifdef CONFIG_NET_SCHED
|
|
if (dev->qdisc != &noop_qdisc)
|
|
qdisc_hash_add(dev->qdisc, false);
|
|
#endif
|
|
}
|
|
|
|
static void transition_one_qdisc(struct net_device *dev,
|
|
struct netdev_queue *dev_queue,
|
|
void *_need_watchdog)
|
|
{
|
|
struct Qdisc *new_qdisc = dev_queue->qdisc_sleeping;
|
|
int *need_watchdog_p = _need_watchdog;
|
|
|
|
if (!(new_qdisc->flags & TCQ_F_BUILTIN))
|
|
clear_bit(__QDISC_STATE_DEACTIVATED, &new_qdisc->state);
|
|
|
|
rcu_assign_pointer(dev_queue->qdisc, new_qdisc);
|
|
if (need_watchdog_p) {
|
|
dev_queue->trans_start = 0;
|
|
*need_watchdog_p = 1;
|
|
}
|
|
}
|
|
|
|
void dev_activate(struct net_device *dev)
|
|
{
|
|
int need_watchdog;
|
|
|
|
/* No queueing discipline is attached to device;
|
|
* create default one for devices, which need queueing
|
|
* and noqueue_qdisc for virtual interfaces
|
|
*/
|
|
|
|
if (dev->qdisc == &noop_qdisc)
|
|
attach_default_qdiscs(dev);
|
|
|
|
if (!netif_carrier_ok(dev))
|
|
/* Delay activation until next carrier-on event */
|
|
return;
|
|
|
|
need_watchdog = 0;
|
|
netdev_for_each_tx_queue(dev, transition_one_qdisc, &need_watchdog);
|
|
if (dev_ingress_queue(dev))
|
|
transition_one_qdisc(dev, dev_ingress_queue(dev), NULL);
|
|
|
|
if (need_watchdog) {
|
|
netif_trans_update(dev);
|
|
dev_watchdog_up(dev);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(dev_activate);
|
|
|
|
static void dev_deactivate_queue(struct net_device *dev,
|
|
struct netdev_queue *dev_queue,
|
|
void *_qdisc_default)
|
|
{
|
|
struct Qdisc *qdisc_default = _qdisc_default;
|
|
struct Qdisc *qdisc;
|
|
|
|
qdisc = rtnl_dereference(dev_queue->qdisc);
|
|
if (qdisc) {
|
|
bool nolock = qdisc->flags & TCQ_F_NOLOCK;
|
|
|
|
if (nolock)
|
|
spin_lock_bh(&qdisc->seqlock);
|
|
spin_lock_bh(qdisc_lock(qdisc));
|
|
|
|
if (!(qdisc->flags & TCQ_F_BUILTIN))
|
|
set_bit(__QDISC_STATE_DEACTIVATED, &qdisc->state);
|
|
|
|
rcu_assign_pointer(dev_queue->qdisc, qdisc_default);
|
|
qdisc_reset(qdisc);
|
|
|
|
spin_unlock_bh(qdisc_lock(qdisc));
|
|
if (nolock)
|
|
spin_unlock_bh(&qdisc->seqlock);
|
|
}
|
|
}
|
|
|
|
static bool some_qdisc_is_busy(struct net_device *dev)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < dev->num_tx_queues; i++) {
|
|
struct netdev_queue *dev_queue;
|
|
spinlock_t *root_lock;
|
|
struct Qdisc *q;
|
|
int val;
|
|
|
|
dev_queue = netdev_get_tx_queue(dev, i);
|
|
q = dev_queue->qdisc_sleeping;
|
|
|
|
root_lock = qdisc_lock(q);
|
|
spin_lock_bh(root_lock);
|
|
|
|
val = (qdisc_is_running(q) ||
|
|
test_bit(__QDISC_STATE_SCHED, &q->state));
|
|
|
|
spin_unlock_bh(root_lock);
|
|
|
|
if (val)
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
static void dev_qdisc_reset(struct net_device *dev,
|
|
struct netdev_queue *dev_queue,
|
|
void *none)
|
|
{
|
|
struct Qdisc *qdisc = dev_queue->qdisc_sleeping;
|
|
|
|
if (qdisc)
|
|
qdisc_reset(qdisc);
|
|
}
|
|
|
|
/**
|
|
* dev_deactivate_many - deactivate transmissions on several devices
|
|
* @head: list of devices to deactivate
|
|
*
|
|
* This function returns only when all outstanding transmissions
|
|
* have completed, unless all devices are in dismantle phase.
|
|
*/
|
|
void dev_deactivate_many(struct list_head *head)
|
|
{
|
|
struct net_device *dev;
|
|
|
|
list_for_each_entry(dev, head, close_list) {
|
|
netdev_for_each_tx_queue(dev, dev_deactivate_queue,
|
|
&noop_qdisc);
|
|
if (dev_ingress_queue(dev))
|
|
dev_deactivate_queue(dev, dev_ingress_queue(dev),
|
|
&noop_qdisc);
|
|
|
|
dev_watchdog_down(dev);
|
|
}
|
|
|
|
/* Wait for outstanding qdisc-less dev_queue_xmit calls.
|
|
* This is avoided if all devices are in dismantle phase :
|
|
* Caller will call synchronize_net() for us
|
|
*/
|
|
synchronize_net();
|
|
|
|
/* Wait for outstanding qdisc_run calls. */
|
|
list_for_each_entry(dev, head, close_list) {
|
|
while (some_qdisc_is_busy(dev)) {
|
|
/* wait_event() would avoid this sleep-loop but would
|
|
* require expensive checks in the fast paths of packet
|
|
* processing which isn't worth it.
|
|
*/
|
|
schedule_timeout_uninterruptible(1);
|
|
}
|
|
/* The new qdisc is assigned at this point so we can safely
|
|
* unwind stale skb lists and qdisc statistics
|
|
*/
|
|
netdev_for_each_tx_queue(dev, dev_qdisc_reset, NULL);
|
|
if (dev_ingress_queue(dev))
|
|
dev_qdisc_reset(dev, dev_ingress_queue(dev), NULL);
|
|
}
|
|
}
|
|
|
|
void dev_deactivate(struct net_device *dev)
|
|
{
|
|
LIST_HEAD(single);
|
|
|
|
list_add(&dev->close_list, &single);
|
|
dev_deactivate_many(&single);
|
|
list_del(&single);
|
|
}
|
|
EXPORT_SYMBOL(dev_deactivate);
|
|
|
|
static int qdisc_change_tx_queue_len(struct net_device *dev,
|
|
struct netdev_queue *dev_queue)
|
|
{
|
|
struct Qdisc *qdisc = dev_queue->qdisc_sleeping;
|
|
const struct Qdisc_ops *ops = qdisc->ops;
|
|
|
|
if (ops->change_tx_queue_len)
|
|
return ops->change_tx_queue_len(qdisc, dev->tx_queue_len);
|
|
return 0;
|
|
}
|
|
|
|
int dev_qdisc_change_tx_queue_len(struct net_device *dev)
|
|
{
|
|
bool up = dev->flags & IFF_UP;
|
|
unsigned int i;
|
|
int ret = 0;
|
|
|
|
if (up)
|
|
dev_deactivate(dev);
|
|
|
|
for (i = 0; i < dev->num_tx_queues; i++) {
|
|
ret = qdisc_change_tx_queue_len(dev, &dev->_tx[i]);
|
|
|
|
/* TODO: revert changes on a partial failure */
|
|
if (ret)
|
|
break;
|
|
}
|
|
|
|
if (up)
|
|
dev_activate(dev);
|
|
return ret;
|
|
}
|
|
|
|
static void dev_init_scheduler_queue(struct net_device *dev,
|
|
struct netdev_queue *dev_queue,
|
|
void *_qdisc)
|
|
{
|
|
struct Qdisc *qdisc = _qdisc;
|
|
|
|
rcu_assign_pointer(dev_queue->qdisc, qdisc);
|
|
dev_queue->qdisc_sleeping = qdisc;
|
|
}
|
|
|
|
void dev_init_scheduler(struct net_device *dev)
|
|
{
|
|
dev->qdisc = &noop_qdisc;
|
|
netdev_for_each_tx_queue(dev, dev_init_scheduler_queue, &noop_qdisc);
|
|
if (dev_ingress_queue(dev))
|
|
dev_init_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc);
|
|
|
|
timer_setup(&dev->watchdog_timer, dev_watchdog, 0);
|
|
}
|
|
|
|
static void shutdown_scheduler_queue(struct net_device *dev,
|
|
struct netdev_queue *dev_queue,
|
|
void *_qdisc_default)
|
|
{
|
|
struct Qdisc *qdisc = dev_queue->qdisc_sleeping;
|
|
struct Qdisc *qdisc_default = _qdisc_default;
|
|
|
|
if (qdisc) {
|
|
rcu_assign_pointer(dev_queue->qdisc, qdisc_default);
|
|
dev_queue->qdisc_sleeping = qdisc_default;
|
|
|
|
qdisc_put(qdisc);
|
|
}
|
|
}
|
|
|
|
void dev_shutdown(struct net_device *dev)
|
|
{
|
|
netdev_for_each_tx_queue(dev, shutdown_scheduler_queue, &noop_qdisc);
|
|
if (dev_ingress_queue(dev))
|
|
shutdown_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc);
|
|
qdisc_put(dev->qdisc);
|
|
dev->qdisc = &noop_qdisc;
|
|
|
|
WARN_ON(timer_pending(&dev->watchdog_timer));
|
|
}
|
|
|
|
void psched_ratecfg_precompute(struct psched_ratecfg *r,
|
|
const struct tc_ratespec *conf,
|
|
u64 rate64)
|
|
{
|
|
memset(r, 0, sizeof(*r));
|
|
r->overhead = conf->overhead;
|
|
r->rate_bytes_ps = max_t(u64, conf->rate, rate64);
|
|
r->linklayer = (conf->linklayer & TC_LINKLAYER_MASK);
|
|
r->mult = 1;
|
|
/*
|
|
* The deal here is to replace a divide by a reciprocal one
|
|
* in fast path (a reciprocal divide is a multiply and a shift)
|
|
*
|
|
* Normal formula would be :
|
|
* time_in_ns = (NSEC_PER_SEC * len) / rate_bps
|
|
*
|
|
* We compute mult/shift to use instead :
|
|
* time_in_ns = (len * mult) >> shift;
|
|
*
|
|
* We try to get the highest possible mult value for accuracy,
|
|
* but have to make sure no overflows will ever happen.
|
|
*/
|
|
if (r->rate_bytes_ps > 0) {
|
|
u64 factor = NSEC_PER_SEC;
|
|
|
|
for (;;) {
|
|
r->mult = div64_u64(factor, r->rate_bytes_ps);
|
|
if (r->mult & (1U << 31) || factor & (1ULL << 63))
|
|
break;
|
|
factor <<= 1;
|
|
r->shift++;
|
|
}
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(psched_ratecfg_precompute);
|
|
|
|
static void mini_qdisc_rcu_func(struct rcu_head *head)
|
|
{
|
|
}
|
|
|
|
void mini_qdisc_pair_swap(struct mini_Qdisc_pair *miniqp,
|
|
struct tcf_proto *tp_head)
|
|
{
|
|
/* Protected with chain0->filter_chain_lock.
|
|
* Can't access chain directly because tp_head can be NULL.
|
|
*/
|
|
struct mini_Qdisc *miniq_old =
|
|
rcu_dereference_protected(*miniqp->p_miniq, 1);
|
|
struct mini_Qdisc *miniq;
|
|
|
|
if (!tp_head) {
|
|
RCU_INIT_POINTER(*miniqp->p_miniq, NULL);
|
|
/* Wait for flying RCU callback before it is freed. */
|
|
rcu_barrier();
|
|
return;
|
|
}
|
|
|
|
miniq = !miniq_old || miniq_old == &miniqp->miniq2 ?
|
|
&miniqp->miniq1 : &miniqp->miniq2;
|
|
|
|
/* We need to make sure that readers won't see the miniq
|
|
* we are about to modify. So wait until previous call_rcu callback
|
|
* is done.
|
|
*/
|
|
rcu_barrier();
|
|
miniq->filter_list = tp_head;
|
|
rcu_assign_pointer(*miniqp->p_miniq, miniq);
|
|
|
|
if (miniq_old)
|
|
/* This is counterpart of the rcu barriers above. We need to
|
|
* block potential new user of miniq_old until all readers
|
|
* are not seeing it.
|
|
*/
|
|
call_rcu(&miniq_old->rcu, mini_qdisc_rcu_func);
|
|
}
|
|
EXPORT_SYMBOL(mini_qdisc_pair_swap);
|
|
|
|
void mini_qdisc_pair_init(struct mini_Qdisc_pair *miniqp, struct Qdisc *qdisc,
|
|
struct mini_Qdisc __rcu **p_miniq)
|
|
{
|
|
miniqp->miniq1.cpu_bstats = qdisc->cpu_bstats;
|
|
miniqp->miniq1.cpu_qstats = qdisc->cpu_qstats;
|
|
miniqp->miniq2.cpu_bstats = qdisc->cpu_bstats;
|
|
miniqp->miniq2.cpu_qstats = qdisc->cpu_qstats;
|
|
miniqp->p_miniq = p_miniq;
|
|
}
|
|
EXPORT_SYMBOL(mini_qdisc_pair_init);
|