pkt_sched: Make default qdisc nonshared-multiqueue safe.

Instead of 'pfifo_fast' we have just plain 'fifo_fast'.
No priority queues, just a straight FIFO.

This is necessary in order to legally have a seperate
qdisc per queue in multi-TX-queue setups, and thus get
full parallelization.

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2008-07-17 01:46:06 -07:00
parent 93245dd6d3
commit a0c80b80e0

View File

@ -349,99 +349,44 @@ static struct Qdisc noqueue_qdisc = {
};
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
static inline struct sk_buff_head *prio2list(struct sk_buff *skb,
struct Qdisc *qdisc)
static int fifo_fast_enqueue(struct sk_buff *skb, struct Qdisc* qdisc)
{
struct sk_buff_head *list = qdisc_priv(qdisc);
return list + prio2band[skb->priority & TC_PRIO_MAX];
}
struct sk_buff_head *list = &qdisc->q;
static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc* qdisc)
{
struct sk_buff_head *list = prio2list(skb, qdisc);
if (skb_queue_len(list) < qdisc_dev(qdisc)->tx_queue_len) {
qdisc->q.qlen++;
if (skb_queue_len(list) < qdisc_dev(qdisc)->tx_queue_len)
return __qdisc_enqueue_tail(skb, qdisc, list);
}
return qdisc_drop(skb, qdisc);
}
static struct sk_buff *pfifo_fast_dequeue(struct Qdisc* qdisc)
static struct sk_buff *fifo_fast_dequeue(struct Qdisc* qdisc)
{
int prio;
struct sk_buff_head *list = qdisc_priv(qdisc);
struct sk_buff_head *list = &qdisc->q;
for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) {
if (!skb_queue_empty(list + prio)) {
qdisc->q.qlen--;
return __qdisc_dequeue_head(qdisc, list + prio);
}
}
if (!skb_queue_empty(list))
return __qdisc_dequeue_head(qdisc, list);
return NULL;
}
static int pfifo_fast_requeue(struct sk_buff *skb, struct Qdisc* qdisc)
static int fifo_fast_requeue(struct sk_buff *skb, struct Qdisc* qdisc)
{
qdisc->q.qlen++;
return __qdisc_requeue(skb, qdisc, prio2list(skb, qdisc));
return __qdisc_requeue(skb, qdisc, &qdisc->q);
}
static void pfifo_fast_reset(struct Qdisc* qdisc)
static void fifo_fast_reset(struct Qdisc* qdisc)
{
int prio;
struct sk_buff_head *list = qdisc_priv(qdisc);
for (prio = 0; prio < PFIFO_FAST_BANDS; prio++)
__qdisc_reset_queue(qdisc, list + prio);
__qdisc_reset_queue(qdisc, &qdisc->q);
qdisc->qstats.backlog = 0;
qdisc->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);
NLA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
return skb->len;
nla_put_failure:
return -1;
}
static int pfifo_fast_init(struct Qdisc *qdisc, struct nlattr *opt)
{
int prio;
struct sk_buff_head *list = qdisc_priv(qdisc);
for (prio = 0; prio < PFIFO_FAST_BANDS; prio++)
skb_queue_head_init(list + prio);
return 0;
}
static struct Qdisc_ops pfifo_fast_ops __read_mostly = {
.id = "pfifo_fast",
.priv_size = PFIFO_FAST_BANDS * sizeof(struct sk_buff_head),
.enqueue = pfifo_fast_enqueue,
.dequeue = pfifo_fast_dequeue,
.requeue = pfifo_fast_requeue,
.init = pfifo_fast_init,
.reset = pfifo_fast_reset,
.dump = pfifo_fast_dump,
static struct Qdisc_ops fifo_fast_ops __read_mostly = {
.id = "fifo_fast",
.priv_size = 0,
.enqueue = fifo_fast_enqueue,
.dequeue = fifo_fast_dequeue,
.requeue = fifo_fast_requeue,
.reset = fifo_fast_reset,
.owner = THIS_MODULE,
};
@ -570,7 +515,7 @@ static void attach_one_default_qdisc(struct net_device *dev,
if (dev->tx_queue_len) {
qdisc = qdisc_create_dflt(dev, dev_queue,
&pfifo_fast_ops, TC_H_ROOT);
&fifo_fast_ops, TC_H_ROOT);
if (!qdisc) {
printk(KERN_INFO "%s: activation failed\n", dev->name);
return;
@ -601,9 +546,9 @@ void dev_activate(struct net_device *dev)
int need_watchdog;
/* No queueing discipline is attached to device;
create default one i.e. pfifo_fast for devices,
which need queueing and noqueue_qdisc for
virtual interfaces
* create default one i.e. fifo_fast for devices,
* which need queueing and noqueue_qdisc for
* virtual interfaces.
*/
if (dev_all_qdisc_sleeping_noop(dev))