Release 4.11 net/sched/sch_generic.c

/*
 * net/sched/sch_generic.c      Generic packet scheduler routines.
 *
 *              This program is free software; you can redistribute it and/or
 *              modify it under the terms of the GNU General Public License
 *              as published by the Free Software Foundation; either version
 *              2 of the License, or (at your option) any later version.
 *
 * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 *              Jamal Hadi Salim, <hadi@cyberus.ca> 990601
 *              - Ingress support
 */

#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/init.h>
#include <linux/rcupdate.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/if_vlan.h>
#include <net/sch_generic.h>
#include <net/pkt_sched.h>
#include <net/dst.h>

/* Qdisc to use by default */

const struct Qdisc_ops *default_qdisc_ops = &pfifo_fast_ops;

EXPORT_SYMBOL(default_qdisc_ops);

/* Main transmission queue. */

/* Modifications to data participating in scheduling must be protected with
 * qdisc_lock(qdisc) spinlock.
 *
 * The idea is the following:
 * - enqueue, dequeue are serialized via qdisc root lock
 * - ingress filtering is also serialized via qdisc root lock
 * - updates to tree and tree walking are only done under the rtnl mutex.
 */



static inline int dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q)
{
	q->gso_skb = skb;
	q->qstats.requeues++;
	qdisc_qstats_backlog_inc(q, skb);
	q->q.qlen++;	/* it's still part of the queue */
	__netif_schedule(q);

	return 0;
}

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Jarek Poplawski
13
24.53%
2
22.22%
Krishna Kumar
9
16.98%
2
22.22%
Américo Wang
7
13.21%
1
11.11%
David S. Miller
2
3.77%
1
11.11%
Linus Torvalds (pre-git)
2
3.77%
1
11.11%
Andi Kleen
1
1.89%
1
11.11%
Total
53
100.00%
9
100.00%



static void try_bulk_dequeue_skb(struct Qdisc *q,
				 struct sk_buff *skb,
				 const struct netdev_queue *txq,
				 int *packets)
{
	int bytelimit = qdisc_avail_bulklimit(txq) - skb->len;

	while (bytelimit > 0) {
		struct sk_buff *nskb = q->dequeue(q);

		if (!nskb)
			break;

		bytelimit -= nskb->len; /* covers GSO len */
		skb->next = nskb;
		skb = nskb;
		(*packets)++; /* GSO counts as one pkt */
	}
	skb->next = NULL;
}

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/* This variant of try_bulk_dequeue_skb() makes sure
 * all skbs in the chain are for the same txq
 */


static void try_bulk_dequeue_skb_slow(struct Qdisc *q,
				      struct sk_buff *skb,
				      int *packets)
{
	int mapping = skb_get_queue_mapping(skb);
	struct sk_buff *nskb;
	int cnt = 0;

	do {
		nskb = q->dequeue(q);
		if (!nskb)
			break;
		if (unlikely(skb_get_queue_mapping(nskb) != mapping)) {
			q->skb_bad_txq = nskb;
			qdisc_qstats_backlog_inc(q, nskb);
			q->q.qlen++;
			break;
		}
		skb->next = nskb;
		skb = nskb;
	} while (++cnt < 8);
	(*packets) += cnt;
	skb->next = NULL;
}

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/* Note that dequeue_skb can possibly return a SKB list (via skb->next).
 * A requeued skb (via q->gso_skb) can also be a SKB list.
 */


static struct sk_buff *dequeue_skb(struct Qdisc *q, bool *validate,
				   int *packets)
{
	struct sk_buff *skb = q->gso_skb;
	const struct netdev_queue *txq = q->dev_queue;

	*packets = 1;
	if (unlikely(skb)) {
		/* skb in gso_skb were already validated */
		*validate = false;
		/* check the reason of requeuing without tx lock first */
		txq = skb_get_tx_queue(txq->dev, skb);
		if (!netif_xmit_frozen_or_stopped(txq)) {
			q->gso_skb = NULL;
			qdisc_qstats_backlog_dec(q, skb);
			q->q.qlen--;
		} else
			skb = NULL;
		return skb;
	}
	*validate = true;
	skb = q->skb_bad_txq;
	if (unlikely(skb)) {
		/* check the reason of requeuing without tx lock first */
		txq = skb_get_tx_queue(txq->dev, skb);
		if (!netif_xmit_frozen_or_stopped(txq)) {
			q->skb_bad_txq = NULL;
			qdisc_qstats_backlog_dec(q, skb);
			q->q.qlen--;
			goto bulk;
		}
		return NULL;
	}
	if (!(q->flags & TCQ_F_ONETXQUEUE) ||
	    !netif_xmit_frozen_or_stopped(txq))
		skb = q->dequeue(q);
	if (skb) {
bulk:
		if (qdisc_may_bulk(q))
			try_bulk_dequeue_skb(q, skb, txq, packets);
		else
			try_bulk_dequeue_skb_slow(q, skb, packets);
	}
	return skb;
}

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37
15.23%
2
13.33%
Jamal Hadi Salim
29
11.93%
1
6.67%
Jesper Dangaard Brouer
23
9.47%
2
13.33%
Krishna Kumar
9
3.70%
1
6.67%
David S. Miller
8
3.29%
3
20.00%
Américo Wang
7
2.88%
1
6.67%
Daniel Borkmann
1
0.41%
1
6.67%
Tom Herbert
1
0.41%
1
6.67%
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243
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15
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/*
 * Transmit possibly several skbs, and handle the return status as
 * required. Owning running seqcount bit guarantees that
 * only one CPU can execute this function.
 *
 * Returns to the caller:
 *                              0  - queue is empty or throttled.
 *                              >0 - queue is not empty.
 */


int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
		    struct net_device *dev, struct netdev_queue *txq,
		    spinlock_t *root_lock, bool validate)
{
	int ret = NETDEV_TX_BUSY;

	/* And release qdisc */
	spin_unlock(root_lock);

	/* Note that we validate skb (GSO, checksum, ...) outside of locks */
	if (validate)
		skb = validate_xmit_skb_list(skb, dev);

	if (likely(skb)) {
		HARD_TX_LOCK(dev, txq, smp_processor_id());
		if (!netif_xmit_frozen_or_stopped(txq))
			skb = dev_hard_start_xmit(skb, dev, txq, &ret);

		HARD_TX_UNLOCK(dev, txq);
	} else {
		spin_lock(root_lock);
		return qdisc_qlen(q);
	}
	spin_lock(root_lock);

	if (dev_xmit_complete(ret)) {
		/* Driver sent out skb successfully or skb was consumed */
		ret = qdisc_qlen(q);
	} else {
		/* Driver returned NETDEV_TX_BUSY - requeue skb */
		if (unlikely(ret != NETDEV_TX_BUSY))
			net_warn_ratelimited("BUG %s code %d qlen %d\n",
					     dev->name, ret, q->q.qlen);

		ret = dev_requeue_skb(skb, q);
	}

	if (ret && netif_xmit_frozen_or_stopped(txq))
		ret = 0;

	return ret;
}

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23.08%
Krishna Kumar
31
15.82%
2
7.69%
Eric Dumazet
25
12.76%
2
7.69%
Lars Persson
16
8.16%
1
3.85%
Linus Torvalds (pre-git)
15
7.65%
4
15.38%
Jarek Poplawski
8
4.08%
1
3.85%
Stephen Hemminger
8
4.08%
1
3.85%
Peter P. Waskiewicz Jr
7
3.57%
1
3.85%
Herbert Xu
5
2.55%
3
11.54%
Tom Herbert
2
1.02%
1
3.85%
Thomas Graf
2
1.02%
1
3.85%
Joe Perches
1
0.51%
1
3.85%
Total
196
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26
100.00%

/*
 * NOTE: Called under qdisc_lock(q) with locally disabled BH.
 *
 * running seqcount guarantees only one CPU can process
 * this qdisc at a time. qdisc_lock(q) serializes queue accesses for
 * this queue.
 *
 *  netif_tx_lock serializes accesses to device driver.
 *
 *  qdisc_lock(q) and netif_tx_lock are mutually exclusive,
 *  if one is grabbed, another must be free.
 *
 * Note, that this procedure can be called by a watchdog timer
 *
 * Returns to the caller:
 *                              0  - queue is empty or throttled.
 *                              >0 - queue is not empty.
 *
 */


static inline int qdisc_restart(struct Qdisc *q, int *packets)
{
	struct netdev_queue *txq;
	struct net_device *dev;
	spinlock_t *root_lock;
	struct sk_buff *skb;
	bool validate;

	/* Dequeue packet */
	skb = dequeue_skb(q, &validate, packets);
	if (unlikely(!skb))
		return 0;

	root_lock = qdisc_lock(q);
	dev = qdisc_dev(q);
	txq = skb_get_tx_queue(dev, skb);

	return sch_direct_xmit(skb, q, dev, txq, root_lock, validate);
}

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8
7.92%
1
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Jesper Dangaard Brouer
6
5.94%
1
25.00%
Daniel Borkmann
1
0.99%
1
25.00%
Total
101
100.00%
4
100.00%



void __qdisc_run(struct Qdisc *q)
{
	int quota = dev_tx_weight;
	int packets;

	while (qdisc_restart(q, &packets)) {
		/*
                 * Ordered by possible occurrence: Postpone processing if
                 * 1. we've exceeded packet quota
                 * 2. another process needs the CPU;
                 */
		quota -= packets;
		if (quota <= 0 || need_resched()) {
			__netif_schedule(q);
			break;
		}
	}

	qdisc_run_end(q);
}

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David S. Miller
6
10.53%
2
20.00%
Jamal Hadi Salim
6
10.53%
1
10.00%
Krishna Kumar
2
3.51%
1
10.00%
Matthias Tafelmeier
1
1.75%
1
10.00%
Eric Dumazet
1
1.75%
1
10.00%
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57
100.00%
10
100.00%



unsigned long dev_trans_start(struct net_device *dev)
{
	unsigned long val, res;
	unsigned int i;

	if (is_vlan_dev(dev))
		dev = vlan_dev_real_dev(dev);
	res = netdev_get_tx_queue(dev, 0)->trans_start;
	for (i = 1; i < dev->num_tx_queues; i++) {
		val = netdev_get_tx_queue(dev, i)->trans_start;
		if (val && time_after(val, res))
			res = val;
	}

	return res;
}
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1
33.33%
Florian Westphal
6
6.52%
1
33.33%
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92
100.00%
3
100.00%


EXPORT_SYMBOL(dev_trans_start);



static void dev_watchdog(unsigned long arg)
{
	struct net_device *dev = (struct net_device *)arg;

	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) {
				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);
}

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Eric Dumazet
26
12.56%
1
6.25%
Arjan van de Ven
11
5.31%
3
18.75%
Stephen Hemminger
8
3.86%
2
12.50%
David Decotigny
5
2.42%
1
6.25%
Herbert Xu
2
0.97%
1
6.25%
Tom Herbert
1
0.48%
1
6.25%
Total
207
100.00%
16
100.00%



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);
	}
}

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11.11%
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3
4.92%
1
11.11%
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61
100.00%
9
100.00%



static void dev_watchdog_up(struct net_device *dev)
{
	__netdev_watchdog_up(dev);
}

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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);
}

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1
2.78%
1
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/**
 *      netif_carrier_on - set carrier
 *      @dev: network device
 *
 * Device has detected that 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_changes);
		linkwatch_fire_event(dev);
		if (netif_running(dev))
			__netdev_watchdog_up(dev);
	}
}
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13.79%
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Jeff Garzik
2
3.45%
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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_changes);
		linkwatch_fire_event(dev);
	}
}
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3
100.00%


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;
}

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3
100.00%



static struct sk_buff *noop_dequeue(struct Qdisc *qdisc)
{
	return NULL;
}

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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 = {
	.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),
};

EXPORT_SYMBOL(noop_qdisc);



static int noqueue_init(struct Qdisc *qdisc, struct nlattr *opt)
{
	/* 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;
}

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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:
 *      - queues for the three band
 *      - bitmap indicating which of the bands contain skbs
 */

struct pfifo_fast_priv {
	
u32 bitmap;
	
struct qdisc_skb_head q[PFIFO_FAST_BANDS];
};

/*
 * Convert a bitmap to the first band number where an skb is queued, where:
 *      bitmap=0 means there are no skbs on any band.
 *      bitmap=1 means there is an skb on band 0.
 *      bitmap=7 means there are skbs on all 3 bands, etc.
 */

static const int bitmap2band[] = {-1, 0, 1, 0, 2, 0, 1, 0};



static inline struct qdisc_skb_head *band2list(struct pfifo_fast_priv *priv,
					     int band)
{
	return priv->q + band;
}

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Florian Westphal
1
4.17%
1
20.00%
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24
100.00%
5
100.00%



static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc *qdisc,
			      struct sk_buff **to_free)
{
	if (qdisc->q.qlen < qdisc_dev(qdisc)->tx_queue_len) {
		int band = prio2band[skb->priority & TC_PRIO_MAX];
		struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
		struct qdisc_skb_head *list = band2list(priv, band);

		priv->bitmap |= (1 << band);
		qdisc->q.qlen++;
		return __qdisc_enqueue_tail(skb, qdisc, list);
	}

	return qdisc_drop(skb, qdisc, to_free);
}

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27.27%
1
10.00%
Thomas Graf
12
10.91%
2
20.00%
Eric Dumazet
8
7.27%
1
10.00%
Linus Torvalds (pre-git)
6
5.45%
1
10.00%
Florian Westphal
3
2.73%
2
20.00%
Jamal Hadi Salim
2
1.82%
1
10.00%
Total
110
100.00%
10
100.00%



static struct sk_buff *pfifo_fast_dequeue(struct Qdisc *qdisc)
{
	struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
	int band = bitmap2band[priv->bitmap];

	if (likely(band >= 0)) {
		struct qdisc_skb_head *qh = band2list(priv, band);
		struct sk_buff *skb = __qdisc_dequeue_head(qh);

		if (likely(skb != NULL)) {
			qdisc_qstats_backlog_dec(qdisc, skb);
			qdisc_bstats_update(qdisc, skb);
		}

		qdisc->q.qlen--;
		if (qh->qlen == 0)
			priv->bitmap &= ~(1 << band);

		return skb;
	}

	return NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Krishna Kumar
51
41.46%
1
16.67%
Florian Westphal
33
26.83%
2
33.33%
Linus Torvalds (pre-git)
24
19.51%
1
16.67%
David S. Miller
13
10.57%
1
16.67%
Thomas Graf
2
1.63%
1
16.67%
Total
123
100.00%
6
100.00%



static struct sk_buff *pfifo_fast_peek(struct Qdisc *qdisc)
{
	struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
	int band = bitmap2band[priv->bitmap];

	if (band >= 0) {
		struct qdisc_skb_head *qh = band2list(priv, band);

		return qh->head;
	}

	return NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Jarek Poplawski
30
49.18%
1
33.33%
Krishna Kumar
26
42.62%
1
33.33%
Florian Westphal
5
8.20%
1
33.33%
Total
61
100.00%
3
100.00%



static void pfifo_fast_reset(struct Qdisc *qdisc)
{
	int prio;
	struct pfifo_fast_priv *priv = qdisc_priv(qdisc);

	for (prio = 0; prio < PFIFO_FAST_BANDS; prio++)
		__qdisc_reset_queue(band2list(priv, prio));

	priv->bitmap = 0;
	qdisc->qstats.backlog = 0;
	qdisc->q.qlen = 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
David S. Miller
35
50.72%
1
16.67%
Linus Torvalds (pre-git)
14
20.29%
3
50.00%
Krishna Kumar
13
18.84%
1
16.67%
Thomas Graf
7
10.14%
1
16.67%
Total
69
100.00%
6
100.00%



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;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
David S. Miller
72
100.00%
2
100.00%
Total
72
100.00%
2
100.00%



static int pfifo_fast_init(struct Qdisc *qdisc, struct nlattr *opt)
{
	int prio;
	struct pfifo_fast_priv *priv = qdisc_priv(qdisc);

	for (prio = 0; prio < PFIFO_FAST_BANDS; prio++)
		qdisc_skb_head_init(band2list(priv, prio));

	/* Can by-pass the queue discipline */
	qdisc->flags |= TCQ_F_CAN_BYPASS;
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
David S. Miller
46
74.19%
1
20.00%
Krishna Kumar
7
11.29%
1
20.00%
Eric Dumazet
7
11.29%
1
20.00%
Linus Torvalds (pre-git)
1
1.61%
1
20.00%
Florian Westphal
1
1.61%
1
20.00%
Total
62
100.00%
5
100.00%


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,
	.reset		=	pfifo_fast_reset,
	.dump		=	pfifo_fast_dump,
	.owner		=	THIS_MODULE,
};

EXPORT_SYMBOL(pfifo_fast_ops);


static struct lock_class_key qdisc_tx_busylock;

static struct lock_class_key qdisc_running_key;



struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
			  const struct Qdisc_ops *ops)
{
	void *p;
	struct Qdisc *sch;
	unsigned int size = QDISC_ALIGN(sizeof(*sch)) + ops->priv_size;
	int err = -ENOBUFS;
	struct net_device *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;
	}
	qdisc_skb_head_init(&sch->q);
	spin_lock_init(&sch->q.lock);

	spin_lock_init(&sch->busylock);
	lockdep_set_class(&sch->busylock,
			  dev->qdisc_tx_busylock ?: &qdisc_tx_busylock);

	seqcount_init(&sch->running);
	lockdep_set_class(&sch->running,
			  dev->qdisc_running_key ?: &qdisc_running_key);

	sch->ops = ops;
	sch->enqueue = ops->enqueue;
	sch->dequeue = ops->dequeue;
	sch->dev_queue = dev_queue;
	dev_hold(dev);
	atomic_set(&sch->refcnt, 1);

	return sch;
errout:
	return ERR_PTR(err);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Eric Dumazet
124
42.91%
5
35.71%
Linus Torvalds (pre-git)
71
24.57%
3
21.43%
Stephen Hemminger
40
13.84%
2
14.29%
Thomas Graf
30
10.38%
1
7.14%
Florian Westphal
11
3.81%
1
7.14%
David S. Miller
9
3.11%
1
7.14%
Patrick McHardy
4
1.38%
1
7.14%
Total
289
100.00%
14
100.00%



struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
				const struct Qdisc_ops *ops,
				unsigned int parentid)
{
	struct Qdisc *sch;

	if (!try_module_get(ops->owner))
		return NULL;

	sch = qdisc_alloc(dev_queue, ops);
	if (IS_ERR(sch)) {
		module_put(ops->owner);
		return NULL;
	}
	sch->parent = parentid;

	if (!ops->init || ops->init(sch, NULL) == 0)
		return sch;

	qdisc_destroy(sch);
	return NULL;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Thomas Graf
35
33.98%
2
20.00%
Linus Torvalds (pre-git)
25
24.27%
3
30.00%
Eric Dumazet
15
14.56%
1
10.00%
Stephen Hemminger
11
10.68%
2
20.00%
Patrick McHardy
10
9.71%
1
10.00%
David S. Miller
7
6.80%
1
10.00%
Total
103
100.00%
10
100.00%


EXPORT_SYMBOL(qdisc_create_dflt);

/* Under qdisc_lock(qdisc) and BH! */



void qdisc_reset(struct Qdisc *qdisc)
{
	const struct Qdisc_ops *ops = qdisc->ops;

	if (ops->reset)
		ops->reset(qdisc);

	kfree_skb(qdisc->skb_bad_txq);
	qdisc->skb_bad_txq = NULL;

	if (qdisc->gso_skb) {
		kfree_skb_list(qdisc->gso_skb);
		qdisc->gso_skb = NULL;
	}
	qdisc->q.qlen = 0;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
31
41.33%
1
16.67%
Krishna Kumar
16
21.33%
1
16.67%
Eric Dumazet
15
20.00%
2
33.33%
Jarek Poplawski
12
16.00%
1
16.67%
Jesper Dangaard Brouer
1
1.33%
1
16.67%
Total
75
100.00%
6
100.00%


EXPORT_SYMBOL(qdisc_reset);



static void qdisc_rcu_free(struct rcu_head *head)
{
	struct Qdisc *qdisc = container_of(head, struct Qdisc, rcu_head);

	if (qdisc_is_percpu_stats(qdisc)) {
		free_percpu(qdisc->cpu_bstats);
		free_percpu(qdisc->cpu_qstats);
	}

	kfree((char *) qdisc - qdisc->padded);
}

Contributors
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Commits
CommitProp