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Diffstat (limited to 'net/sched/sch_netem.c')
-rw-r--r--net/sched/sch_netem.c49
1 files changed, 34 insertions, 15 deletions
diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index 38d9aa0cd30e..4ad39a4a3cf5 100644
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -105,6 +105,11 @@ struct netem_sched_data {
u32 rho;
} delay_cor, loss_cor, dup_cor, reorder_cor, corrupt_cor;
+ struct prng {
+ u64 seed;
+ struct rnd_state prng_state;
+ } prng;
+
struct disttable *delay_dist;
enum {
@@ -179,15 +184,16 @@ static void init_crandom(struct crndstate *state, unsigned long rho)
* Next number depends on last value.
* rho is scaled to avoid floating point.
*/
-static u32 get_crandom(struct crndstate *state)
+static u32 get_crandom(struct crndstate *state, struct prng *p)
{
u64 value, rho;
unsigned long answer;
+ struct rnd_state *s = &p->prng_state;
if (!state || state->rho == 0) /* no correlation */
- return get_random_u32();
+ return prandom_u32_state(s);
- value = get_random_u32();
+ value = prandom_u32_state(s);
rho = (u64)state->rho + 1;
answer = (value * ((1ull<<32) - rho) + state->last * rho) >> 32;
state->last = answer;
@@ -201,7 +207,7 @@ static u32 get_crandom(struct crndstate *state)
static bool loss_4state(struct netem_sched_data *q)
{
struct clgstate *clg = &q->clg;
- u32 rnd = get_random_u32();
+ u32 rnd = prandom_u32_state(&q->prng.prng_state);
/*
* Makes a comparison between rnd and the transition
@@ -266,18 +272,19 @@ static bool loss_4state(struct netem_sched_data *q)
static bool loss_gilb_ell(struct netem_sched_data *q)
{
struct clgstate *clg = &q->clg;
+ struct rnd_state *s = &q->prng.prng_state;
switch (clg->state) {
case GOOD_STATE:
- if (get_random_u32() < clg->a1)
+ if (prandom_u32_state(s) < clg->a1)
clg->state = BAD_STATE;
- if (get_random_u32() < clg->a4)
+ if (prandom_u32_state(s) < clg->a4)
return true;
break;
case BAD_STATE:
- if (get_random_u32() < clg->a2)
+ if (prandom_u32_state(s) < clg->a2)
clg->state = GOOD_STATE;
- if (get_random_u32() > clg->a3)
+ if (prandom_u32_state(s) > clg->a3)
return true;
}
@@ -289,7 +296,7 @@ static bool loss_event(struct netem_sched_data *q)
switch (q->loss_model) {
case CLG_RANDOM:
/* Random packet drop 0 => none, ~0 => all */
- return q->loss && q->loss >= get_crandom(&q->loss_cor);
+ return q->loss && q->loss >= get_crandom(&q->loss_cor, &q->prng);
case CLG_4_STATES:
/* 4state loss model algorithm (used also for GI model)
@@ -318,6 +325,7 @@ static bool loss_event(struct netem_sched_data *q)
*/
static s64 tabledist(s64 mu, s32 sigma,
struct crndstate *state,
+ struct prng *prng,
const struct disttable *dist)
{
s64 x;
@@ -327,7 +335,7 @@ static s64 tabledist(s64 mu, s32 sigma,
if (sigma == 0)
return mu;
- rnd = get_crandom(state);
+ rnd = get_crandom(state, prng);
/* default uniform distribution */
if (dist == NULL)
@@ -449,7 +457,7 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch,
skb->prev = NULL;
/* Random duplication */
- if (q->duplicate && q->duplicate >= get_crandom(&q->dup_cor))
+ if (q->duplicate && q->duplicate >= get_crandom(&q->dup_cor, &q->prng))
++count;
/* Drop packet? */
@@ -492,7 +500,7 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch,
* If packet is going to be hardware checksummed, then
* do it now in software before we mangle it.
*/
- if (q->corrupt && q->corrupt >= get_crandom(&q->corrupt_cor)) {
+ if (q->corrupt && q->corrupt >= get_crandom(&q->corrupt_cor, &q->prng)) {
if (skb_is_gso(skb)) {
skb = netem_segment(skb, sch, to_free);
if (!skb)
@@ -530,12 +538,12 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch,
cb = netem_skb_cb(skb);
if (q->gap == 0 || /* not doing reordering */
q->counter < q->gap - 1 || /* inside last reordering gap */
- q->reorder < get_crandom(&q->reorder_cor)) {
+ q->reorder < get_crandom(&q->reorder_cor, &q->prng)) {
u64 now;
s64 delay;
delay = tabledist(q->latency, q->jitter,
- &q->delay_cor, q->delay_dist);
+ &q->delay_cor, &q->prng, q->delay_dist);
now = ktime_get_ns();
@@ -639,7 +647,7 @@ static void get_slot_next(struct netem_sched_data *q, u64 now)
else
next_delay = tabledist(q->slot_config.dist_delay,
(s32)(q->slot_config.dist_jitter),
- NULL, q->slot_dist);
+ NULL, &q->prng, q->slot_dist);
q->slot.slot_next = now + next_delay;
q->slot.packets_left = q->slot_config.max_packets;
@@ -922,6 +930,7 @@ static const struct nla_policy netem_policy[TCA_NETEM_MAX + 1] = {
[TCA_NETEM_LATENCY64] = { .type = NLA_S64 },
[TCA_NETEM_JITTER64] = { .type = NLA_S64 },
[TCA_NETEM_SLOT] = { .len = sizeof(struct tc_netem_slot) },
+ [TCA_NETEM_PRNG_SEED] = { .type = NLA_U64 },
};
static int parse_attr(struct nlattr *tb[], int maxtype, struct nlattr *nla,
@@ -1040,6 +1049,12 @@ static int netem_change(struct Qdisc *sch, struct nlattr *opt,
/* capping jitter to the range acceptable by tabledist() */
q->jitter = min_t(s64, abs(q->jitter), INT_MAX);
+ if (tb[TCA_NETEM_PRNG_SEED])
+ q->prng.seed = nla_get_u64(tb[TCA_NETEM_PRNG_SEED]);
+ else
+ q->prng.seed = get_random_u64();
+ prandom_seed_state(&q->prng.prng_state, q->prng.seed);
+
unlock:
sch_tree_unlock(sch);
@@ -1203,6 +1218,10 @@ static int netem_dump(struct Qdisc *sch, struct sk_buff *skb)
goto nla_put_failure;
}
+ if (nla_put_u64_64bit(skb, TCA_NETEM_PRNG_SEED, q->prng.seed,
+ TCA_NETEM_PAD))
+ goto nla_put_failure;
+
return nla_nest_end(skb, nla);
nla_put_failure:
generated by cgit (git 2.34.1) at 2024-06-13 20:18:31 +0000