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Diffstat (limited to 'net/sched/sch_netem.c')
-rw-r--r--net/sched/sch_netem.c79
1 files changed, 49 insertions, 30 deletions
diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index de1059af6da..f1669a00f57 100644
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -117,6 +117,11 @@ struct netem_sched_data {
LOST_IN_BURST_PERIOD,
} _4_state_model;
+ enum {
+ GOOD_STATE = 1,
+ BAD_STATE,
+ } GE_state_model;
+
/* Correlated Loss Generation models */
struct clgstate {
/* state of the Markov chain */
@@ -272,15 +277,15 @@ static bool loss_gilb_ell(struct netem_sched_data *q)
struct clgstate *clg = &q->clg;
switch (clg->state) {
- case 1:
+ case GOOD_STATE:
if (prandom_u32() < clg->a1)
- clg->state = 2;
+ clg->state = BAD_STATE;
if (prandom_u32() < clg->a4)
return true;
break;
- case 2:
+ case BAD_STATE:
if (prandom_u32() < clg->a2)
- clg->state = 1;
+ clg->state = GOOD_STATE;
if (prandom_u32() > clg->a3)
return true;
}
@@ -689,9 +694,8 @@ static int get_dist_table(struct Qdisc *sch, const struct nlattr *attr)
return 0;
}
-static void get_correlation(struct Qdisc *sch, const struct nlattr *attr)
+static void get_correlation(struct netem_sched_data *q, const struct nlattr *attr)
{
- struct netem_sched_data *q = qdisc_priv(sch);
const struct tc_netem_corr *c = nla_data(attr);
init_crandom(&q->delay_cor, c->delay_corr);
@@ -699,27 +703,24 @@ static void get_correlation(struct Qdisc *sch, const struct nlattr *attr)
init_crandom(&q->dup_cor, c->dup_corr);
}
-static void get_reorder(struct Qdisc *sch, const struct nlattr *attr)
+static void get_reorder(struct netem_sched_data *q, const struct nlattr *attr)
{
- struct netem_sched_data *q = qdisc_priv(sch);
const struct tc_netem_reorder *r = nla_data(attr);
q->reorder = r->probability;
init_crandom(&q->reorder_cor, r->correlation);
}
-static void get_corrupt(struct Qdisc *sch, const struct nlattr *attr)
+static void get_corrupt(struct netem_sched_data *q, const struct nlattr *attr)
{
- struct netem_sched_data *q = qdisc_priv(sch);
const struct tc_netem_corrupt *r = nla_data(attr);
q->corrupt = r->probability;
init_crandom(&q->corrupt_cor, r->correlation);
}
-static void get_rate(struct Qdisc *sch, const struct nlattr *attr)
+static void get_rate(struct netem_sched_data *q, 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;
@@ -732,9 +733,8 @@ static void get_rate(struct Qdisc *sch, const struct nlattr *attr)
q->cell_size_reciprocal = (struct reciprocal_value) { 0 };
}
-static int get_loss_clg(struct Qdisc *sch, const struct nlattr *attr)
+static int get_loss_clg(struct netem_sched_data *q, const struct nlattr *attr)
{
- struct netem_sched_data *q = qdisc_priv(sch);
const struct nlattr *la;
int rem;
@@ -752,7 +752,7 @@ static int get_loss_clg(struct Qdisc *sch, const struct nlattr *attr)
q->loss_model = CLG_4_STATES;
- q->clg.state = 1;
+ q->clg.state = TX_IN_GAP_PERIOD;
q->clg.a1 = gi->p13;
q->clg.a2 = gi->p31;
q->clg.a3 = gi->p32;
@@ -770,7 +770,7 @@ static int get_loss_clg(struct Qdisc *sch, const struct nlattr *attr)
}
q->loss_model = CLG_GILB_ELL;
- q->clg.state = 1;
+ q->clg.state = GOOD_STATE;
q->clg.a1 = ge->p;
q->clg.a2 = ge->r;
q->clg.a3 = ge->h;
@@ -821,6 +821,8 @@ static int netem_change(struct Qdisc *sch, struct nlattr *opt)
struct netem_sched_data *q = qdisc_priv(sch);
struct nlattr *tb[TCA_NETEM_MAX + 1];
struct tc_netem_qopt *qopt;
+ struct clgstate old_clg;
+ int old_loss_model = CLG_RANDOM;
int ret;
if (opt == NULL)
@@ -831,6 +833,33 @@ static int netem_change(struct Qdisc *sch, struct nlattr *opt)
if (ret < 0)
return ret;
+ /* backup q->clg and q->loss_model */
+ old_clg = q->clg;
+ old_loss_model = q->loss_model;
+
+ if (tb[TCA_NETEM_LOSS]) {
+ ret = get_loss_clg(q, tb[TCA_NETEM_LOSS]);
+ if (ret) {
+ q->loss_model = old_loss_model;
+ return ret;
+ }
+ } else {
+ q->loss_model = CLG_RANDOM;
+ }
+
+ if (tb[TCA_NETEM_DELAY_DIST]) {
+ ret = get_dist_table(sch, tb[TCA_NETEM_DELAY_DIST]);
+ if (ret) {
+ /* recover clg and loss_model, in case of
+ * q->clg and q->loss_model were modified
+ * in get_loss_clg()
+ */
+ q->clg = old_clg;
+ q->loss_model = old_loss_model;
+ return ret;
+ }
+ }
+
sch->limit = qopt->limit;
q->latency = qopt->latency;
@@ -848,22 +877,16 @@ static int netem_change(struct Qdisc *sch, struct nlattr *opt)
q->reorder = ~0;
if (tb[TCA_NETEM_CORR])
- get_correlation(sch, tb[TCA_NETEM_CORR]);
-
- if (tb[TCA_NETEM_DELAY_DIST]) {
- ret = get_dist_table(sch, tb[TCA_NETEM_DELAY_DIST]);
- if (ret)
- return ret;
- }
+ get_correlation(q, tb[TCA_NETEM_CORR]);
if (tb[TCA_NETEM_REORDER])
- get_reorder(sch, tb[TCA_NETEM_REORDER]);
+ get_reorder(q, tb[TCA_NETEM_REORDER]);
if (tb[TCA_NETEM_CORRUPT])
- get_corrupt(sch, tb[TCA_NETEM_CORRUPT]);
+ get_corrupt(q, tb[TCA_NETEM_CORRUPT]);
if (tb[TCA_NETEM_RATE])
- get_rate(sch, tb[TCA_NETEM_RATE]);
+ get_rate(q, tb[TCA_NETEM_RATE]);
if (tb[TCA_NETEM_RATE64])
q->rate = max_t(u64, q->rate,
@@ -872,10 +895,6 @@ static int netem_change(struct Qdisc *sch, struct nlattr *opt)
if (tb[TCA_NETEM_ECN])
q->ecn = nla_get_u32(tb[TCA_NETEM_ECN]);
- q->loss_model = CLG_RANDOM;
- if (tb[TCA_NETEM_LOSS])
- ret = get_loss_clg(sch, tb[TCA_NETEM_LOSS]);
-
return ret;
}