libnl 1.1

Stochastic Fairness Queueing (SFQ)

Queueing Discipline Modules

Attribute Access

int rtnl_sfq_set_quantum (struct rtnl_qdisc *qdisc, int quantum)
 Set quantum of SFQ qdisc.
int rtnl_sfq_get_quantum (struct rtnl_qdisc *qdisc)
 Get quantum of SFQ qdisc.
int rtnl_sfq_set_limit (struct rtnl_qdisc *qdisc, int limit)
 Set limit of SFQ qdisc.
int rtnl_sfq_get_limit (struct rtnl_qdisc *qdisc)
 Get limit of SFQ qdisc.
int rtnl_sfq_set_perturb (struct rtnl_qdisc *qdisc, int perturb)
 Set perturbation interval of SFQ qdisc.
int rtnl_sfq_get_perturb (struct rtnl_qdisc *qdisc)
 Get perturbation interval of SFQ qdisc.
int rtnl_sfq_get_divisor (struct rtnl_qdisc *qdisc)
 Get divisor of SFQ qdisc.

Detailed Description

Parameter Description
  • Quantum: Number of bytes to send out per slot and round.
  • Perturbation: Timer period between changing the hash function.
  • Limit: Upper limit of queue in number of packets before SFQ starts dropping packets.
  • Divisor: Hash table divisor, i.e. size of hash table.

Function Documentation

int rtnl_sfq_set_quantum ( struct rtnl_qdisc *  qdisc,
int  quantum 
)
Parameters:
qdiscSFQ qdisc to be modified.
quantumNew quantum in bytes.
Returns:
0 on success or a negative error code.

Definition at line 154 of file sfq.c.

{
        struct rtnl_sfq *sfq;
        
        sfq = sfq_alloc(qdisc);
        if (!sfq)
                return nl_errno(ENOMEM);

        sfq->qs_quantum = quantum;
        sfq->qs_mask |= SCH_SFQ_ATTR_QUANTUM;

        return 0;
}
int rtnl_sfq_get_quantum ( struct rtnl_qdisc *  qdisc)
Parameters:
qdiscSFQ qdisc.
Returns:
Quantum in bytes or a negative error code.

Definition at line 173 of file sfq.c.

{
        struct rtnl_sfq *sfq;

        sfq = sfq_qdisc(qdisc);
        if (sfq && sfq->qs_mask & SCH_SFQ_ATTR_QUANTUM)
                return sfq->qs_quantum;
        else
                return nl_errno(ENOENT);
}
int rtnl_sfq_set_limit ( struct rtnl_qdisc *  qdisc,
int  limit 
)
Parameters:
qdiscSFQ qdisc to be modified.
limitNew limit in number of packets.
Returns:
0 on success or a negative error code.

Definition at line 190 of file sfq.c.

{
        struct rtnl_sfq *sfq;

        sfq = sfq_alloc(qdisc);
        if (!sfq)
                return nl_errno(ENOMEM);

        sfq->qs_limit = limit;
        sfq->qs_mask |= SCH_SFQ_ATTR_LIMIT;

        return 0;
}
int rtnl_sfq_get_limit ( struct rtnl_qdisc *  qdisc)
Parameters:
qdiscSFQ qdisc.
Returns:
Limit or a negative error code.

Definition at line 209 of file sfq.c.

{
        struct rtnl_sfq *sfq;

        sfq = sfq_qdisc(qdisc);
        if (sfq && sfq->qs_mask & SCH_SFQ_ATTR_LIMIT)
                return sfq->qs_limit;
        else
                return nl_errno(ENOENT);
}
int rtnl_sfq_set_perturb ( struct rtnl_qdisc *  qdisc,
int  perturb 
)
Parameters:
qdiscSFQ qdisc to be modified.
perturbNew perturbation interval in seconds.
Note:
A value of 0 disables perturbation altogether.
Returns:
0 on success or a negative error code.

Definition at line 227 of file sfq.c.

{
        struct rtnl_sfq *sfq;

        sfq = sfq_alloc(qdisc);
        if (!sfq)
                return nl_errno(ENOMEM);

        sfq->qs_perturb = perturb;
        sfq->qs_mask |= SCH_SFQ_ATTR_PERTURB;

        return 0;
}
int rtnl_sfq_get_perturb ( struct rtnl_qdisc *  qdisc)
Parameters:
qdiscSFQ qdisc.
Returns:
Perturbation interval in seconds or a negative error code.

Definition at line 246 of file sfq.c.

{
        struct rtnl_sfq *sfq;

        sfq = sfq_qdisc(qdisc);
        if (sfq && sfq->qs_mask & SCH_SFQ_ATTR_PERTURB)
                return sfq->qs_perturb;
        else
                return nl_errno(ENOENT);
}
int rtnl_sfq_get_divisor ( struct rtnl_qdisc *  qdisc)
Parameters:
qdiscSFQ qdisc.
Returns:
Divisor in number of entries or a negative error code.

Definition at line 262 of file sfq.c.

{
        struct rtnl_sfq *sfq;

        sfq = sfq_qdisc(qdisc);
        if (sfq && sfq->qs_mask & SCH_SFQ_ATTR_DIVISOR)
                return sfq->qs_divisor;
        else
                return nl_errno(ENOENT);
}