summaryrefslogtreecommitdiff
path: root/net/sched/sch_netem.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/sched/sch_netem.c')
-rw-r--r--net/sched/sch_netem.c285
1 files changed, 157 insertions, 128 deletions
diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index eb3b9a86c6ed..e7e1d0b57b3d 100644
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -22,6 +22,7 @@
#include <linux/skbuff.h>
#include <linux/vmalloc.h>
#include <linux/rtnetlink.h>
+#include <linux/reciprocal_div.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
@@ -66,7 +67,11 @@
*/
struct netem_sched_data {
+ /* internal t(ime)fifo qdisc uses sch->q and sch->limit */
+
+ /* optional qdisc for classful handling (NULL at netem init) */
struct Qdisc *qdisc;
+
struct qdisc_watchdog watchdog;
psched_tdiff_t latency;
@@ -79,6 +84,11 @@ struct netem_sched_data {
u32 duplicate;
u32 reorder;
u32 corrupt;
+ u32 rate;
+ s32 packet_overhead;
+ u32 cell_size;
+ u32 cell_size_reciprocal;
+ s32 cell_overhead;
struct crndstate {
u32 last;
@@ -111,7 +121,9 @@ struct netem_sched_data {
};
-/* Time stamp put into socket buffer control block */
+/* Time stamp put into socket buffer control block
+ * Only valid when skbs are in our internal t(ime)fifo queue.
+ */
struct netem_skb_cb {
psched_time_t time_to_send;
};
@@ -298,6 +310,51 @@ static psched_tdiff_t tabledist(psched_tdiff_t mu, psched_tdiff_t sigma,
return x / NETEM_DIST_SCALE + (sigma / NETEM_DIST_SCALE) * t + mu;
}
+static psched_time_t packet_len_2_sched_time(unsigned int len, struct netem_sched_data *q)
+{
+ u64 ticks;
+
+ len += q->packet_overhead;
+
+ if (q->cell_size) {
+ u32 cells = reciprocal_divide(len, q->cell_size_reciprocal);
+
+ if (len > cells * q->cell_size) /* extra cell needed for remainder */
+ cells++;
+ len = cells * (q->cell_size + q->cell_overhead);
+ }
+
+ ticks = (u64)len * NSEC_PER_SEC;
+
+ do_div(ticks, q->rate);
+ return PSCHED_NS2TICKS(ticks);
+}
+
+static int tfifo_enqueue(struct sk_buff *nskb, struct Qdisc *sch)
+{
+ struct sk_buff_head *list = &sch->q;
+ psched_time_t tnext = netem_skb_cb(nskb)->time_to_send;
+ struct sk_buff *skb;
+
+ if (likely(skb_queue_len(list) < sch->limit)) {
+ skb = skb_peek_tail(list);
+ /* Optimize for add at tail */
+ if (likely(!skb || tnext >= netem_skb_cb(skb)->time_to_send))
+ return qdisc_enqueue_tail(nskb, sch);
+
+ skb_queue_reverse_walk(list, skb) {
+ if (tnext >= netem_skb_cb(skb)->time_to_send)
+ break;
+ }
+
+ __skb_queue_after(list, skb, nskb);
+ sch->qstats.backlog += qdisc_pkt_len(nskb);
+ return NET_XMIT_SUCCESS;
+ }
+
+ return qdisc_reshape_fail(nskb, sch);
+}
+
/*
* Insert one skb into qdisc.
* Note: parent depends on return value to account for queue length.
@@ -371,9 +428,27 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch)
&q->delay_cor, q->delay_dist);
now = psched_get_time();
+
+ if (q->rate) {
+ struct sk_buff_head *list = &sch->q;
+
+ delay += packet_len_2_sched_time(skb->len, q);
+
+ if (!skb_queue_empty(list)) {
+ /*
+ * Last packet in queue is reference point (now).
+ * First packet in queue is already in flight,
+ * calculate this time bonus and substract
+ * from delay.
+ */
+ delay -= now - netem_skb_cb(skb_peek(list))->time_to_send;
+ now = netem_skb_cb(skb_peek_tail(list))->time_to_send;
+ }
+ }
+
cb->time_to_send = now + delay;
++q->counter;
- ret = qdisc_enqueue(skb, q->qdisc);
+ ret = tfifo_enqueue(skb, sch);
} else {
/*
* Do re-ordering by putting one out of N packets at the front
@@ -382,9 +457,9 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch)
cb->time_to_send = psched_get_time();
q->counter = 0;
- __skb_queue_head(&q->qdisc->q, skb);
- q->qdisc->qstats.backlog += qdisc_pkt_len(skb);
- q->qdisc->qstats.requeues++;
+ __skb_queue_head(&sch->q, skb);
+ sch->qstats.backlog += qdisc_pkt_len(skb);
+ sch->qstats.requeues++;
ret = NET_XMIT_SUCCESS;
}
@@ -395,19 +470,20 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch)
}
}
- sch->q.qlen++;
return NET_XMIT_SUCCESS;
}
static unsigned int netem_drop(struct Qdisc *sch)
{
struct netem_sched_data *q = qdisc_priv(sch);
- unsigned int len = 0;
+ unsigned int len;
- if (q->qdisc->ops->drop && (len = q->qdisc->ops->drop(q->qdisc)) != 0) {
- sch->q.qlen--;
+ len = qdisc_queue_drop(sch);
+ if (!len && q->qdisc && q->qdisc->ops->drop)
+ len = q->qdisc->ops->drop(q->qdisc);
+ if (len)
sch->qstats.drops++;
- }
+
return len;
}
@@ -419,16 +495,16 @@ static struct sk_buff *netem_dequeue(struct Qdisc *sch)
if (qdisc_is_throttled(sch))
return NULL;
- skb = q->qdisc->ops->peek(q->qdisc);
+tfifo_dequeue:
+ skb = qdisc_peek_head(sch);
if (skb) {
const struct netem_skb_cb *cb = netem_skb_cb(skb);
- psched_time_t now = psched_get_time();
/* if more time remaining? */
- if (cb->time_to_send <= now) {
- skb = qdisc_dequeue_peeked(q->qdisc);
+ if (cb->time_to_send <= psched_get_time()) {
+ skb = qdisc_dequeue_tail(sch);
if (unlikely(!skb))
- return NULL;
+ goto qdisc_dequeue;
#ifdef CONFIG_NET_CLS_ACT
/*
@@ -439,15 +515,37 @@ static struct sk_buff *netem_dequeue(struct Qdisc *sch)
skb->tstamp.tv64 = 0;
#endif
- sch->q.qlen--;
+ if (q->qdisc) {
+ int err = qdisc_enqueue(skb, q->qdisc);
+
+ if (unlikely(err != NET_XMIT_SUCCESS)) {
+ if (net_xmit_drop_count(err)) {
+ sch->qstats.drops++;
+ qdisc_tree_decrease_qlen(sch, 1);
+ }
+ }
+ goto tfifo_dequeue;
+ }
+deliver:
qdisc_unthrottled(sch);
qdisc_bstats_update(sch, skb);
return skb;
}
+ if (q->qdisc) {
+ skb = q->qdisc->ops->dequeue(q->qdisc);
+ if (skb)
+ goto deliver;
+ }
qdisc_watchdog_schedule(&q->watchdog, cb->time_to_send);
}
+qdisc_dequeue:
+ if (q->qdisc) {
+ skb = q->qdisc->ops->dequeue(q->qdisc);
+ if (skb)
+ goto deliver;
+ }
return NULL;
}
@@ -455,8 +553,9 @@ static void netem_reset(struct Qdisc *sch)
{
struct netem_sched_data *q = qdisc_priv(sch);
- qdisc_reset(q->qdisc);
- sch->q.qlen = 0;
+ qdisc_reset_queue(sch);
+ if (q->qdisc)
+ qdisc_reset(q->qdisc);
qdisc_watchdog_cancel(&q->watchdog);
}
@@ -488,7 +587,7 @@ static int get_dist_table(struct Qdisc *sch, const struct nlattr *attr)
return -EINVAL;
s = sizeof(struct disttable) + n * sizeof(s16);
- d = kmalloc(s, GFP_KERNEL);
+ d = kmalloc(s, GFP_KERNEL | __GFP_NOWARN);
if (!d)
d = vmalloc(s);
if (!d)
@@ -501,9 +600,10 @@ static int get_dist_table(struct Qdisc *sch, const struct nlattr *attr)
root_lock = qdisc_root_sleeping_lock(sch);
spin_lock_bh(root_lock);
- dist_free(q->delay_dist);
- q->delay_dist = d;
+ swap(q->delay_dist, d);
spin_unlock_bh(root_lock);
+
+ dist_free(d);
return 0;
}
@@ -535,6 +635,19 @@ static void get_corrupt(struct Qdisc *sch, const struct nlattr *attr)
init_crandom(&q->corrupt_cor, r->correlation);
}
+static void get_rate(struct Qdisc *sch, const struct nlattr *attr)
+{
+ struct netem_sched_data *q = qdisc_priv(sch);
+ const struct tc_netem_rate *r = nla_data(attr);
+
+ q->rate = r->rate;
+ q->packet_overhead = r->packet_overhead;
+ q->cell_size = r->cell_size;
+ if (q->cell_size)
+ q->cell_size_reciprocal = reciprocal_value(q->cell_size);
+ q->cell_overhead = r->cell_overhead;
+}
+
static int get_loss_clg(struct Qdisc *sch, const struct nlattr *attr)
{
struct netem_sched_data *q = qdisc_priv(sch);
@@ -548,7 +661,7 @@ static int get_loss_clg(struct Qdisc *sch, const struct nlattr *attr)
case NETEM_LOSS_GI: {
const struct tc_netem_gimodel *gi = nla_data(la);
- if (nla_len(la) != sizeof(struct tc_netem_gimodel)) {
+ if (nla_len(la) < sizeof(struct tc_netem_gimodel)) {
pr_info("netem: incorrect gi model size\n");
return -EINVAL;
}
@@ -567,8 +680,8 @@ static int get_loss_clg(struct Qdisc *sch, const struct nlattr *attr)
case NETEM_LOSS_GE: {
const struct tc_netem_gemodel *ge = nla_data(la);
- if (nla_len(la) != sizeof(struct tc_netem_gemodel)) {
- pr_info("netem: incorrect gi model size\n");
+ if (nla_len(la) < sizeof(struct tc_netem_gemodel)) {
+ pr_info("netem: incorrect ge model size\n");
return -EINVAL;
}
@@ -594,6 +707,7 @@ static const struct nla_policy netem_policy[TCA_NETEM_MAX + 1] = {
[TCA_NETEM_CORR] = { .len = sizeof(struct tc_netem_corr) },
[TCA_NETEM_REORDER] = { .len = sizeof(struct tc_netem_reorder) },
[TCA_NETEM_CORRUPT] = { .len = sizeof(struct tc_netem_corrupt) },
+ [TCA_NETEM_RATE] = { .len = sizeof(struct tc_netem_rate) },
[TCA_NETEM_LOSS] = { .type = NLA_NESTED },
};
@@ -631,11 +745,7 @@ static int netem_change(struct Qdisc *sch, struct nlattr *opt)
if (ret < 0)
return ret;
- ret = fifo_set_limit(q->qdisc, qopt->limit);
- if (ret) {
- pr_info("netem: can't set fifo limit\n");
- return ret;
- }
+ sch->limit = qopt->limit;
q->latency = qopt->latency;
q->jitter = qopt->jitter;
@@ -666,6 +776,9 @@ static int netem_change(struct Qdisc *sch, struct nlattr *opt)
if (tb[TCA_NETEM_CORRUPT])
get_corrupt(sch, tb[TCA_NETEM_CORRUPT]);
+ if (tb[TCA_NETEM_RATE])
+ get_rate(sch, tb[TCA_NETEM_RATE]);
+
q->loss_model = CLG_RANDOM;
if (tb[TCA_NETEM_LOSS])
ret = get_loss_clg(sch, tb[TCA_NETEM_LOSS]);
@@ -673,88 +786,6 @@ static int netem_change(struct Qdisc *sch, struct nlattr *opt)
return ret;
}
-/*
- * Special case version of FIFO queue for use by netem.
- * It queues in order based on timestamps in skb's
- */
-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;
- psched_time_t tnext = netem_skb_cb(nskb)->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 = netem_skb_cb(skb);
-
- if (tnext >= cb->time_to_send)
- break;
- }
-
- __skb_queue_after(list, skb, nskb);
-
- sch->qstats.backlog += qdisc_pkt_len(nskb);
-
- return NET_XMIT_SUCCESS;
- }
-
- return qdisc_reshape_fail(nskb, sch);
-}
-
-static int tfifo_init(struct Qdisc *sch, struct nlattr *opt)
-{
- struct fifo_sched_data *q = qdisc_priv(sch);
-
- if (opt) {
- struct tc_fifo_qopt *ctl = nla_data(opt);
- if (nla_len(opt) < sizeof(*ctl))
- return -EINVAL;
-
- q->limit = ctl->limit;
- } else
- q->limit = max_t(u32, qdisc_dev(sch)->tx_queue_len, 1);
-
- q->oldest = PSCHED_PASTPERFECT;
- return 0;
-}
-
-static int tfifo_dump(struct Qdisc *sch, struct sk_buff *skb)
-{
- struct fifo_sched_data *q = qdisc_priv(sch);
- struct tc_fifo_qopt opt = { .limit = q->limit };
-
- NLA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
- return skb->len;
-
-nla_put_failure:
- return -1;
-}
-
-static struct Qdisc_ops tfifo_qdisc_ops __read_mostly = {
- .id = "tfifo",
- .priv_size = sizeof(struct fifo_sched_data),
- .enqueue = tfifo_enqueue,
- .dequeue = qdisc_dequeue_head,
- .peek = qdisc_peek_head,
- .drop = qdisc_queue_drop,
- .init = tfifo_init,
- .reset = qdisc_reset_queue,
- .change = tfifo_init,
- .dump = tfifo_dump,
-};
-
static int netem_init(struct Qdisc *sch, struct nlattr *opt)
{
struct netem_sched_data *q = qdisc_priv(sch);
@@ -766,18 +797,9 @@ static int netem_init(struct Qdisc *sch, struct nlattr *opt)
qdisc_watchdog_init(&q->watchdog, sch);
q->loss_model = CLG_RANDOM;
- q->qdisc = qdisc_create_dflt(sch->dev_queue, &tfifo_qdisc_ops,
- TC_H_MAKE(sch->handle, 1));
- if (!q->qdisc) {
- pr_notice("netem: qdisc create tfifo qdisc failed\n");
- return -ENOMEM;
- }
-
ret = netem_change(sch, opt);
- if (ret) {
+ if (ret)
pr_info("netem: change failed\n");
- qdisc_destroy(q->qdisc);
- }
return ret;
}
@@ -786,7 +808,8 @@ static void netem_destroy(struct Qdisc *sch)
struct netem_sched_data *q = qdisc_priv(sch);
qdisc_watchdog_cancel(&q->watchdog);
- qdisc_destroy(q->qdisc);
+ if (q->qdisc)
+ qdisc_destroy(q->qdisc);
dist_free(q->delay_dist);
}
@@ -846,6 +869,7 @@ static int netem_dump(struct Qdisc *sch, struct sk_buff *skb)
struct tc_netem_corr cor;
struct tc_netem_reorder reorder;
struct tc_netem_corrupt corrupt;
+ struct tc_netem_rate rate;
qopt.latency = q->latency;
qopt.jitter = q->jitter;
@@ -868,6 +892,12 @@ static int netem_dump(struct Qdisc *sch, struct sk_buff *skb)
corrupt.correlation = q->corrupt_cor.rho;
NLA_PUT(skb, TCA_NETEM_CORRUPT, sizeof(corrupt), &corrupt);
+ rate.rate = q->rate;
+ rate.packet_overhead = q->packet_overhead;
+ rate.cell_size = q->cell_size;
+ rate.cell_overhead = q->cell_overhead;
+ NLA_PUT(skb, TCA_NETEM_RATE, sizeof(rate), &rate);
+
if (dump_loss_model(q, skb) != 0)
goto nla_put_failure;
@@ -883,7 +913,7 @@ static int netem_dump_class(struct Qdisc *sch, unsigned long cl,
{
struct netem_sched_data *q = qdisc_priv(sch);
- if (cl != 1) /* only one class */
+ if (cl != 1 || !q->qdisc) /* only one class */
return -ENOENT;
tcm->tcm_handle |= TC_H_MIN(1);
@@ -897,14 +927,13 @@ static int netem_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
{
struct netem_sched_data *q = qdisc_priv(sch);
- if (new == NULL)
- new = &noop_qdisc;
-
sch_tree_lock(sch);
*old = q->qdisc;
q->qdisc = new;
- qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
- qdisc_reset(*old);
+ if (*old) {
+ qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
+ qdisc_reset(*old);
+ }
sch_tree_unlock(sch);
return 0;