[PATCH] trace: take live traces via telemetry

[Jerin Jacob]

On Thu, Oct 13, 2022 at 1:20 PM David Marchand
<david.marchand at redhat.com> wrote:
>

I would suggest to change the subject as "trace: enable trace
operations via telemetry" or so

> Register telemetry commands to list and configure trace points and later
> save traces for a running DPDK application.
>
> Note: trace point names contain a '.', so the list of valid characters
> used in telemetry commands and dictionary keys has been extended.
>
> Example with testpmd running with two net/null ports (startup command
> from devtools/test-null.sh):
>
> --> /trace/disable,*
> {"/trace/disable": {"Count": 2}}
>
> Signed-off-by: David Marchand <david.marchand at redhat.com>

> +}
> +
> +static int
> +trace_telemetry_list(const char *cmd __rte_unused,
> +       const char *params, struct rte_tel_data *d)
> +{
> +       struct trace_point *tp;
> +
> +       rte_tel_data_start_dict(d);
> +       STAILQ_FOREACH(tp, &tp_list, next) {
> +               if (params != NULL && fnmatch(params, tp->name, 0) != 0)
> +                       continue;
> +
> +               rte_tel_data_add_dict_string(d, tp->name,
> +                       rte_trace_point_is_enabled(tp->handle) ?  "Enabled" : "Disabled");

Could be changed to "Ena" and "Dis" or similar to reduce traffic on wire.

Also, it may be good to add a few text in
doc/guides/prog_guide/trace_lib.rst to tell this feature.

Acked-by: Jerin Jacob <jerinj at marvell.com>