From a0c80b80e0fb48129e4e9d6a9ede914f9ff1850d Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Thu, 17 Jul 2008 01:46:06 -0700 Subject: [PATCH] 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 --- net/sched/sch_generic.c | 99 +++++++++-------------------------------- 1 file changed, 22 insertions(+), 77 deletions(-) diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 8fc580b3e17..e244c462e6b 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -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) -{ - struct sk_buff_head *list = qdisc_priv(qdisc); - return list + prio2band[skb->priority & TC_PRIO_MAX]; -} - -static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc* qdisc) +static int fifo_fast_enqueue(struct sk_buff *skb, struct Qdisc* qdisc) { - struct sk_buff_head *list = prio2list(skb, qdisc); + struct sk_buff_head *list = &qdisc->q; - 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)) -- 2.41.1