Re: [PATCH 3/3] perf/probe: Add --bootconfig to output definition in bootconfig format
From: Masami Hiramatsu
Date: Fri Jun 18 2021 - 11:07:37 EST
On Fri, 18 Jun 2021 10:14:02 -0300
Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> wrote:
> Em Sat, Jun 05, 2021 at 01:28:43AM +0900, Masami Hiramatsu escreveu:
> > Now the boot-time tracing supports the kprobes events and that
> > must be written in bootconfig file as following format.
> >
> > ftrace.event.kprobes.<EVENT_NAME>.probes = <PROBE-DEF>
> >
> > The perf probe already supports --definition (-D) action to
> > show the probe definitions, but the format is for the tracefs.
>
> You forgot to add the tools/perf/Documentation/perf-probe.txt entry for
> this new command line option, please sent it as a followup patch.
Oops, let me write it up! Thanks for pointing!
>
> Applied.
>
> - Arnaldo
>
> > [p|r][:EVENT_NAME] <PROBE-DEF>
> >
> > This adds --bootconfig option for -D action so that it output
> > the probe definitions in bootconfig fromat. E.g.
> >
> > $ perf probe --bootconfig -D "path_lookupat:7 err:s32 s:string"
> > ftrace.event.kprobes.path_lookupat_L7.probe = 'path_lookupat.isra.0+309 err_s32=%ax:s32 s_string=+0(%r13):string'
> >
> > Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> > ---
> > tools/perf/builtin-probe.c | 12 ++++++-
> > tools/perf/util/probe-event.c | 72 +++++++++++++++++++++++++++++++++++++++++
> > tools/perf/util/probe-event.h | 2 +
> > 3 files changed, 85 insertions(+), 1 deletion(-)
> >
> > diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
> > index 6b1507566770..2bfd41df621c 100644
> > --- a/tools/perf/builtin-probe.c
> > +++ b/tools/perf/builtin-probe.c
> > @@ -347,7 +347,10 @@ static int perf_add_probe_events(struct perf_probe_event *pevs, int npevs)
> > goto out_cleanup;
> >
> > if (params.command == 'D') { /* it shows definition */
> > - ret = show_probe_trace_events(pevs, npevs);
> > + if (probe_conf.bootconfig)
> > + ret = show_bootconfig_events(pevs, npevs);
> > + else
> > + ret = show_probe_trace_events(pevs, npevs);
> > goto out_cleanup;
> > }
> >
> > @@ -581,6 +584,8 @@ __cmd_probe(int argc, const char **argv)
> > "Look for files with symbols relative to this directory"),
> > OPT_CALLBACK(0, "target-ns", NULL, "pid",
> > "target pid for namespace contexts", opt_set_target_ns),
> > + OPT_BOOLEAN(0, "bootconfig", &probe_conf.bootconfig,
> > + "Output probe definition with bootconfig format"),
> > OPT_END()
> > };
> > int ret;
> > @@ -692,6 +697,11 @@ __cmd_probe(int argc, const char **argv)
> > }
> > break;
> > case 'D':
> > + if (probe_conf.bootconfig && params.uprobes) {
> > + pr_err(" Error: --bootconfig doesn't support uprobes.\n");
> > + return -EINVAL;
> > + }
> > + __fallthrough;
> > case 'a':
> >
> > /* Ensure the last given target is used */
> > diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
> > index 505c0702dbe2..f1348fa3dd1b 100644
> > --- a/tools/perf/util/probe-event.c
> > +++ b/tools/perf/util/probe-event.c
> > @@ -3564,6 +3564,78 @@ int show_probe_trace_events(struct perf_probe_event *pevs, int npevs)
> > return ret;
> > }
> >
> > +static int show_bootconfig_event(struct probe_trace_event *tev)
> > +{
> > + struct probe_trace_point *tp = &tev->point;
> > + struct strbuf buf;
> > + char *ret = NULL;
> > + int err;
> > +
> > + if (strbuf_init(&buf, 32) < 0)
> > + return -ENOMEM;
> > +
> > + err = synthesize_kprobe_trace_def(tp, &buf);
> > + if (err >= 0)
> > + err = synthesize_probe_trace_args(tev, &buf);
> > + if (err >= 0)
> > + ret = strbuf_detach(&buf, NULL);
> > + strbuf_release(&buf);
> > +
> > + if (ret) {
> > + printf("'%s'", ret);
> > + free(ret);
> > + }
> > +
> > + return err;
> > +}
> > +
> > +int show_bootconfig_events(struct perf_probe_event *pevs, int npevs)
> > +{
> > + struct strlist *namelist = strlist__new(NULL, NULL);
> > + struct probe_trace_event *tev;
> > + struct perf_probe_event *pev;
> > + char *cur_name = NULL;
> > + int i, j, ret = 0;
> > +
> > + if (!namelist)
> > + return -ENOMEM;
> > +
> > + for (j = 0; j < npevs && !ret; j++) {
> > + pev = &pevs[j];
> > + if (pev->group && strcmp(pev->group, "probe"))
> > + pr_warning("WARN: Group name %s is ignored\n", pev->group);
> > + if (pev->uprobes) {
> > + pr_warning("ERROR: Bootconfig doesn't support uprobes\n");
> > + ret = -EINVAL;
> > + break;
> > + }
> > + for (i = 0; i < pev->ntevs && !ret; i++) {
> > + tev = &pev->tevs[i];
> > + /* Skip if the symbol is out of .text or blacklisted */
> > + if (!tev->point.symbol && !pev->uprobes)
> > + continue;
> > +
> > + /* Set new name for tev (and update namelist) */
> > + ret = probe_trace_event__set_name(tev, pev,
> > + namelist, true);
> > + if (ret)
> > + break;
> > +
> > + if (!cur_name || strcmp(cur_name, tev->event)) {
> > + printf("%sftrace.event.kprobes.%s.probe = ",
> > + cur_name ? "\n" : "", tev->event);
> > + cur_name = tev->event;
> > + } else
> > + printf(", ");
> > + ret = show_bootconfig_event(tev);
> > + }
> > + }
> > + printf("\n");
> > + strlist__delete(namelist);
> > +
> > + return ret;
> > +}
> > +
> > int apply_perf_probe_events(struct perf_probe_event *pevs, int npevs)
> > {
> > int i, ret = 0;
> > diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
> > index 4f0eb3a20c36..65769d7949a3 100644
> > --- a/tools/perf/util/probe-event.h
> > +++ b/tools/perf/util/probe-event.h
> > @@ -15,6 +15,7 @@ struct probe_conf {
> > bool force_add;
> > bool no_inlines;
> > bool cache;
> > + bool bootconfig;
> > int max_probes;
> > unsigned long magic_num;
> > };
> > @@ -163,6 +164,7 @@ int add_perf_probe_events(struct perf_probe_event *pevs, int npevs);
> > int convert_perf_probe_events(struct perf_probe_event *pevs, int npevs);
> > int apply_perf_probe_events(struct perf_probe_event *pevs, int npevs);
> > int show_probe_trace_events(struct perf_probe_event *pevs, int npevs);
> > +int show_bootconfig_events(struct perf_probe_event *pevs, int npevs);
> > void cleanup_perf_probe_events(struct perf_probe_event *pevs, int npevs);
> >
> > struct strfilter;
> >
>
> --
>
> - Arnaldo
--
Masami Hiramatsu <mhiramat@xxxxxxxxxx>