On Wed, Apr 17, 2024 at 10:07:27AM -0700, Stephen Hemminger wrote:
> Include what is used here.
>
There are more changes in this patch than just includes cleanup.
> Signed-off-by: Stephen Hemminger <step...@networkplumber.org>
> ---
> lib/latencystats/rte_latencystats.c | 85 ++++++++++++++++++-----------
> 1 file changed, 52 insertions(+), 33 deletions(-)
>
> diff --git a/lib/latencystats/rte_latencystats.c
> b/lib/latencystats/rte_latencystats.c
> index 62038a9f5d..31e7a6eb88 100644
> --- a/lib/latencystats/rte_latencystats.c
> +++ b/lib/latencystats/rte_latencystats.c
> @@ -2,16 +2,25 @@
> * Copyright(c) 2018 Intel Corporation
> */
>
> +#include <errno.h>
> #include <math.h>
> +#include <stdbool.h>
> +#include <stddef.h>
> +#include <string.h>
>
> -#include <rte_string_fns.h>
> -#include <rte_mbuf_dyn.h>
> -#include <rte_log.h>
> +#include <rte_common.h>
> #include <rte_cycles.h>
> +#include <rte_eal.h>
> +#include <rte_errno.h>
> #include <rte_ethdev.h>
> -#include <rte_metrics.h>
> -#include <rte_memzone.h>
> #include <rte_lcore.h>
> +#include <rte_log.h>
> +#include <rte_mbuf.h>
> +#include <rte_mbuf_dyn.h>
> +#include <rte_memzone.h>
> +#include <rte_metrics.h>
> +#include <rte_spinlock.h>
> +#include <rte_string_fns.h>
>
> #include "rte_latencystats.h"
>
> @@ -148,14 +157,15 @@ add_time_stamps(uint16_t pid __rte_unused,
>
> static uint16_t
> calc_latency(uint16_t pid __rte_unused,
> - uint16_t qid __rte_unused,
> - struct rte_mbuf **pkts,
> - uint16_t nb_pkts,
> - void *_ __rte_unused)
> + uint16_t qid __rte_unused,
> + struct rte_mbuf **pkts,
> + uint16_t nb_pkts,
> + void *_ __rte_unused)
> {
> unsigned int i;
> uint64_t now, latency;
> static uint64_t prev_latency;
> + static bool first_sample = true;
>
> now = rte_rdtsc();
>
> @@ -166,32 +176,41 @@ calc_latency(uint16_t pid __rte_unused,
>
> latency = now - *timestamp_dynfield(pkts[i]);
>
> - /*
> - * The jitter is calculated as statistical mean of interpacket
> - * delay variation. The "jitter estimate" is computed by taking
> - * the absolute values of the ipdv sequence and applying an
> - * exponential filter with parameter 1/16 to generate the
> - * estimate. i.e J=J+(|D(i-1,i)|-J)/16. Where J is jitter,
> - * D(i-1,i) is difference in latency of two consecutive packets
> - * i-1 and i.
> - * Reference: Calculated as per RFC 5481, sec 4.1,
> - * RFC 3393 sec 4.5, RFC 1889 sec.
> - */
> - glob_stats->jitter += ((prev_latency - latency) -
> glob_stats->jitter) / 16;
> - if (glob_stats->min_latency == 0)
> - glob_stats->min_latency = latency;
> - else if (latency < glob_stats->min_latency)
> + if (first_sample) {
> + first_sample = false;
> +
> glob_stats->min_latency = latency;
> - else if (latency > glob_stats->max_latency)
> glob_stats->max_latency = latency;
> - /*
> - * The average latency is measured using exponential moving
> - * average, i.e. using EWMA
> - * https://en.wikipedia.org/wiki/Moving_average
> - *
> - * Alpha is .25
> - */
> - glob_stats->avg_latency += (latency - glob_stats->avg_latency)
> / 4;
> + glob_stats->avg_latency = latency;
> + glob_stats->jitter = 0;
> + } else {
> + /*
> + * The jitter is calculated as statistical mean of
> interpacket
> + * delay variation. The "jitter estimate" is computed
> by taking
> + * the absolute values of the ipdv sequence and
> applying an
> + * exponential filter with parameter 1/16 to generate
> the
> + * estimate. i.e J=J+(|D(i-1,i)|-J)/16. Where J is
> jitter,
> + * D(i-1,i) is difference in latency of two consecutive
> packets
> + * i-1 and i.
> + * Reference: Calculated as per RFC 5481, sec 4.1,
> + * RFC 3393 sec 4.5, RFC 1889 sec.
> + */
> + glob_stats->jitter += ((prev_latency - latency)
> + - glob_stats->jitter) / 16;
> + if (latency < glob_stats->min_latency)
> + glob_stats->min_latency = latency;
> + if (latency > glob_stats->max_latency)
> + glob_stats->max_latency = latency;
> + /*
> + * The average latency is measured using exponential
> moving
> + * average, i.e. using EWMA
> + * https://en.wikipedia.org/wiki/Moving_average
> + *
> + * Alpha is .25
> + */
> + glob_stats->avg_latency += (latency -
> glob_stats->avg_latency) / 4;
> + }
> +
> prev_latency = latency;
> }
> rte_spinlock_unlock(&glob_stats->lock);
> --
> 2.43.0
>
