Hi Eelco,
<snip>
>
> +/** trTCM parameters per metered traffic flow. The CIR, EIT, CBS and EBS
Small typo here: EIT to be replaced by EIR.
> +parameters only count bytes of IP packets and do not include link specific
> +headers. The CBS and EBS need to be greater than zero if CIR and EIR are
> +none-zero respectively.*/
> +struct rte_meter_trtcm_rfc4115_params {
> + uint64_t cir; /**< Committed Information Rate (CIR). Measured in
> bytes per second. */
> + uint64_t eir; /**< Excess Information Rate (EIR). Measured in bytes
> per second. */
> + uint64_t cbs; /**< Committed Burst Size (CBS). Measured in bytes.
> */
> + uint64_t ebs; /**< Excess Burst Size (EBS). Measured in bytes. */
> +};
> +
<snip>
> +static inline enum rte_meter_color __rte_experimental
> +rte_meter_trtcm_rfc4115_color_blind_check(
> + struct rte_meter_trtcm_rfc4115 *m,
> + struct rte_meter_trtcm_rfc4115_profile *p,
> + uint64_t time,
> + uint32_t pkt_len)
> +{
> + uint64_t time_diff_tc, time_diff_te, n_periods_tc, n_periods_te, tc,
> te;
> +
> + /* Bucket update */
> + time_diff_tc = time - m->time_tc;
> + time_diff_te = time - m->time_te;
> + n_periods_tc = time_diff_tc / p->cir_period;
> + n_periods_te = time_diff_te / p->eir_period;
> + m->time_tc += n_periods_tc * p->cir_period;
> + m->time_te += n_periods_te * p->eir_period;
> +
> + tc = m->tc + n_periods_tc * p->cir_bytes_per_period;
> + if (tc > p->cbs)
> + tc = p->cbs;
> +
> + te = m->te + n_periods_te * p->eir_bytes_per_period;
> + if (te > p->ebs)
> + te = p->ebs;
> +
> + /* Color logic */
> + if (tc >= pkt_len) {
> + m->tc = tc - pkt_len;
> + m->te = te;
> + return e_RTE_METER_GREEN;
> + } else if (te >= pkt_len) {
> + m->tc = tc;
> + m->te = te - pkt_len;
> + return e_RTE_METER_YELLOW;
> + }
> +
> + /* If we end up here the color is RED */
> + m->tc = tc;
> + m->te = te;
> + return e_RTE_METER_RED;
> +}
> +
Since the branch (tc >= pkt_len) == TRUE always returns, I suggest we remove
the following "else", as it is redundant:
/* Color logic */
if (tc >= pkt_len) {
m->tc = tc - pkt_len;
m->te = te;
return e_RTE_METER_GREEN;
}
if (te >= pkt_len) {
m->tc = tc;
m->te = te - pkt_len;
return e_RTE_METER_YELLOW;
}
/* If we end up here the color is RED */
m->tc = tc;
m->te = te;
return e_RTE_METER_RED;
> +static inline enum rte_meter_color __rte_experimental
> +rte_meter_trtcm_rfc4115_color_aware_check(
> + struct rte_meter_trtcm_rfc4115 *m,
> + struct rte_meter_trtcm_rfc4115_profile *p,
> + uint64_t time,
> + uint32_t pkt_len,
> + enum rte_meter_color pkt_color)
> +{
> + uint64_t time_diff_tc, time_diff_te, n_periods_tc, n_periods_te, tc,
> te;
> +
> + /* Bucket update */
> + time_diff_tc = time - m->time_tc;
> + time_diff_te = time - m->time_te;
> + n_periods_tc = time_diff_tc / p->cir_period;
> + n_periods_te = time_diff_te / p->eir_period;
> + m->time_tc += n_periods_tc * p->cir_period;
> + m->time_te += n_periods_te * p->eir_period;
> +
> + tc = m->tc + n_periods_tc * p->cir_bytes_per_period;
> + if (tc > p->cbs)
> + tc = p->cbs;
> +
> + te = m->te + n_periods_te * p->eir_bytes_per_period;
> + if (te > p->ebs)
> + te = p->ebs;
> +
> + /* Color logic */
> + if (pkt_color == e_RTE_METER_GREEN) {
> + if (tc >= pkt_len) {
> + m->tc = tc - pkt_len;
> + m->te = te;
> + return e_RTE_METER_GREEN;
> + } else if (te >= pkt_len) {
> + m->tc = tc;
> + m->te = te - pkt_len;
> + return e_RTE_METER_YELLOW;
> + }
> + } else if (pkt_color == e_RTE_METER_YELLOW && te >= pkt_len) {
> + m->tc = tc;
> + m->te = te - pkt_len;
> + return e_RTE_METER_YELLOW;
> + }
> +
> + /* If we end up here the color is RED */
> + m->tc = tc;
> + m->te = te;
> + return e_RTE_METER_RED;
> +}
> +
> +
I suggest we follow the logic from the diagram in the RFC rather than the logic
in the text preceding the diagram. Although the two descriptions are equivalent
(after a bit of thinking), the diagram seems more optimal to me:
/* Color logic */
if ((pkt_color == e_RTE_METER_GREEN) && (tc >= pkt_len)) {
m->tc = tc - pkt_len;
m->te = te;
return e_RTE_METER_GREEN;
}
if ((pkt_color != e_RTE_METER_RED) && (te >= pkt_len)) {
m->tc = tc;
m->te = te - pkt_len;
return e_RTE_METER_YELLOW;
}
/* If we end up here the color is RED */
m->tc = tc;
m->te = te;
return e_RTE_METER_RED;
<snip>
Thanks,
Cristian
