]> err.no Git - linux-2.6/blobdiff - net/sched/sch_netem.c
[NET]: Hide the queue_mapping field inside netif_subqueue_stopped
[linux-2.6] / net / sched / sch_netem.c
index 791c615e3aadd9b2ba1321752096082668428d3e..9e5e87e81f002433cf6cac0ea4ac3f8db519b3fc 100644 (file)
  */
 
 #include <linux/module.h>
-#include <linux/bitops.h>
 #include <linux/types.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
-#include <linux/netdevice.h>
 #include <linux/skbuff.h>
 #include <linux/rtnetlink.h>
 
@@ -57,19 +55,20 @@ struct netem_sched_data {
        struct Qdisc    *qdisc;
        struct qdisc_watchdog watchdog;
 
-       u32 latency;
+       psched_tdiff_t latency;
+       psched_tdiff_t jitter;
+
        u32 loss;
        u32 limit;
        u32 counter;
        u32 gap;
-       u32 jitter;
        u32 duplicate;
        u32 reorder;
        u32 corrupt;
 
        struct crndstate {
-               unsigned long last;
-               unsigned long rho;
+               u32 last;
+               u32 rho;
        } delay_cor, loss_cor, dup_cor, reorder_cor, corrupt_cor;
 
        struct disttable {
@@ -96,12 +95,12 @@ static void init_crandom(struct crndstate *state, unsigned long rho)
  * Next number depends on last value.
  * rho is scaled to avoid floating point.
  */
-static unsigned long get_crandom(struct crndstate *state)
+static u32 get_crandom(struct crndstate *state)
 {
        u64 value, rho;
        unsigned long answer;
 
-       if (state->rho == 0)    /* no correllation */
+       if (state->rho == 0)    /* no correlation */
                return net_random();
 
        value = net_random();
@@ -115,11 +114,13 @@ static unsigned long get_crandom(struct crndstate *state)
  * std deviation sigma.  Uses table lookup to approximate the desired
  * distribution, and a uniformly-distributed pseudo-random source.
  */
-static long tabledist(unsigned long mu, long sigma,
-                     struct crndstate *state, const struct disttable *dist)
+static psched_tdiff_t tabledist(psched_tdiff_t mu, psched_tdiff_t sigma,
+                               struct crndstate *state,
+                               const struct disttable *dist)
 {
-       long t, x;
-       unsigned long rnd;
+       psched_tdiff_t x;
+       long t;
+       u32 rnd;
 
        if (sigma == 0)
                return mu;
@@ -214,8 +215,8 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch)
                delay = tabledist(q->latency, q->jitter,
                                  &q->delay_cor, q->delay_dist);
 
-               PSCHED_GET_TIME(now);
-               PSCHED_TADD2(now, delay, cb->time_to_send);
+               now = psched_get_time();
+               cb->time_to_send = now + delay;
                ++q->counter;
                ret = q->qdisc->enqueue(skb, q->qdisc);
        } else {
@@ -223,7 +224,7 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch)
                 * Do re-ordering by putting one out of N packets at the front
                 * of the queue.
                 */
-               PSCHED_GET_TIME(cb->time_to_send);
+               cb->time_to_send = psched_get_time();
                q->counter = 0;
                ret = q->qdisc->ops->requeue(skb, q->qdisc);
        }
@@ -270,30 +271,31 @@ static struct sk_buff *netem_dequeue(struct Qdisc *sch)
        struct netem_sched_data *q = qdisc_priv(sch);
        struct sk_buff *skb;
 
+       smp_mb();
+       if (sch->flags & TCQ_F_THROTTLED)
+               return NULL;
+
        skb = q->qdisc->dequeue(q->qdisc);
        if (skb) {
                const struct netem_skb_cb *cb
                        = (const struct netem_skb_cb *)skb->cb;
-               psched_time_t now;
+               psched_time_t now = psched_get_time();
 
                /* if more time remaining? */
-               PSCHED_GET_TIME(now);
-
-               if (PSCHED_TLESS(cb->time_to_send, now)) {
+               if (cb->time_to_send <= now) {
                        pr_debug("netem_dequeue: return skb=%p\n", skb);
                        sch->q.qlen--;
-                       sch->flags &= ~TCQ_F_THROTTLED;
                        return skb;
-               } else {
-                       qdisc_watchdog_schedule(&q->watchdog, cb->time_to_send);
-
-                       if (q->qdisc->ops->requeue(skb, q->qdisc) != NET_XMIT_SUCCESS) {
-                               qdisc_tree_decrease_qlen(q->qdisc, 1);
-                               sch->qstats.drops++;
-                               printk(KERN_ERR "netem: queue discpline %s could not requeue\n",
-                                      q->qdisc->ops->id);
-                       }
                }
+
+               if (unlikely(q->qdisc->ops->requeue(skb, q->qdisc) != NET_XMIT_SUCCESS)) {
+                       qdisc_tree_decrease_qlen(q->qdisc, 1);
+                       sch->qstats.drops++;
+                       printk(KERN_ERR "netem: %s could not requeue\n",
+                              q->qdisc->ops->id);
+               }
+
+               qdisc_watchdog_schedule(&q->watchdog, cb->time_to_send);
        }
 
        return NULL;
@@ -426,8 +428,8 @@ static int netem_change(struct Qdisc *sch, struct rtattr *opt)
        q->loss = qopt->loss;
        q->duplicate = qopt->duplicate;
 
-       /* for compatiablity with earlier versions.
-        * if gap is set, need to assume 100% probablity
+       /* for compatibility with earlier versions.
+        * if gap is set, need to assume 100% probability
         */
        if (q->gap)
                q->reorder = ~0;
@@ -476,22 +478,28 @@ static int netem_change(struct Qdisc *sch, struct rtattr *opt)
  */
 struct fifo_sched_data {
        u32 limit;
+       psched_time_t oldest;
 };
 
 static int tfifo_enqueue(struct sk_buff *nskb, struct Qdisc *sch)
 {
        struct fifo_sched_data *q = qdisc_priv(sch);
        struct sk_buff_head *list = &sch->q;
-       const struct netem_skb_cb *ncb
-               = (const struct netem_skb_cb *)nskb->cb;
+       psched_time_t tnext = ((struct netem_skb_cb *)nskb->cb)->time_to_send;
        struct sk_buff *skb;
 
        if (likely(skb_queue_len(list) < q->limit)) {
+               /* Optimize for add at tail */
+               if (likely(skb_queue_empty(list) || tnext >= q->oldest)) {
+                       q->oldest = tnext;
+                       return qdisc_enqueue_tail(nskb, sch);
+               }
+
                skb_queue_reverse_walk(list, skb) {
                        const struct netem_skb_cb *cb
                                = (const struct netem_skb_cb *)skb->cb;
 
-                       if (!PSCHED_TLESS(ncb->time_to_send, cb->time_to_send))
+                       if (tnext >= cb->time_to_send)
                                break;
                }
 
@@ -504,7 +512,7 @@ static int tfifo_enqueue(struct sk_buff *nskb, struct Qdisc *sch)
                return NET_XMIT_SUCCESS;
        }
 
-       return qdisc_drop(nskb, sch);
+       return qdisc_reshape_fail(nskb, sch);
 }
 
 static int tfifo_init(struct Qdisc *sch, struct rtattr *opt)
@@ -520,6 +528,7 @@ static int tfifo_init(struct Qdisc *sch, struct rtattr *opt)
        } else
                q->limit = max_t(u32, sch->dev->tx_queue_len, 1);
 
+       q->oldest = PSCHED_PASTPERFECT;
        return 0;
 }