lkml.org 
[lkml]   [2022]   [Jan]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] perf/ftrace: system_wide collection is not effective by default
On Wed, Jan 26, 2022 at 03:47:48PM -0800, Namhyung Kim wrote:
> Hello,
>
> On Wed, Jan 26, 2022 at 7:19 AM Changbin Du <changbin.du@gmail.com> wrote:
> >
> > The ftrace.target.system_wide must be set before invoking
> > evlist__create_maps(), otherwise it has no effect.
>
> Oh, right. Thanks for pointing that out.
>
> >
> > Fixes: 53be50282269 ("perf ftrace: Add 'latency' subcommand")
> > Signed-off-by: Changbin Du <changbin.du@gmail.com>
> > ---
> > tools/perf/builtin-ftrace.c | 45 ++++++++++++++++++++-----------------
> > 1 file changed, 24 insertions(+), 21 deletions(-)
> >
> > diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
> > index dec24dc0e767..26bff29ad277 100644
> > --- a/tools/perf/builtin-ftrace.c
> > +++ b/tools/perf/builtin-ftrace.c
> > @@ -1115,6 +1115,7 @@ enum perf_ftrace_subcommand {
> > int cmd_ftrace(int argc, const char **argv)
> > {
> > int ret;
> > + int (*cmd_func)(struct perf_ftrace *) = NULL;
> > struct perf_ftrace ftrace = {
> > .tracer = DEFAULT_TRACER,
> > .target = { .uid = UINT_MAX, },
> > @@ -1221,6 +1222,28 @@ int cmd_ftrace(int argc, const char **argv)
> > goto out_delete_filters;
> > }
> >
> > + switch (subcmd) {
> > + case PERF_FTRACE_TRACE:
> > + if (!argc && target__none(&ftrace.target))
> > + ftrace.target.system_wide = true;
>
> We can move only this part after parse_options().
>
I prefer that all parsing works get be done first. :)

> > + cmd_func = __cmd_ftrace;
> > + break;
> > + case PERF_FTRACE_LATENCY:
> > + if (list_empty(&ftrace.filters)) {
> > + pr_err("Should provide a function to measure\n");
> > + parse_options_usage(ftrace_usage, options, "T", 1);
> > + ret = -EINVAL;
> > + goto out_delete_evlist;
>
> Otherwise, it should go to the out_delete_filters.
>
yes, will fix it.

> > + }
> > + cmd_func = __cmd_latency;
> > + break;
> > + case PERF_FTRACE_NONE:
> > + default:
> > + pr_err("Invalid subcommand\n");
> > + ret = -EINVAL;
> > + goto out_delete_evlist;
>
> Ditto.
>
okay.

> Thanks,
> Namhyung
>
>
> > + }
> > +
> > ret = target__validate(&ftrace.target);
> > if (ret) {
> > char errbuf[512];
> > @@ -1248,27 +1271,7 @@ int cmd_ftrace(int argc, const char **argv)
> > goto out_delete_evlist;
> > }
> >
> > - switch (subcmd) {
> > - case PERF_FTRACE_TRACE:
> > - if (!argc && target__none(&ftrace.target))
> > - ftrace.target.system_wide = true;
> > - ret = __cmd_ftrace(&ftrace);
> > - break;
> > - case PERF_FTRACE_LATENCY:
> > - if (list_empty(&ftrace.filters)) {
> > - pr_err("Should provide a function to measure\n");
> > - parse_options_usage(ftrace_usage, options, "T", 1);
> > - ret = -EINVAL;
> > - goto out_delete_evlist;
> > - }
> > - ret = __cmd_latency(&ftrace);
> > - break;
> > - case PERF_FTRACE_NONE:
> > - default:
> > - pr_err("Invalid subcommand\n");
> > - ret = -EINVAL;
> > - break;
> > - }
> > + ret = cmd_func(&ftrace);
> >
> > out_delete_evlist:
> > evlist__delete(ftrace.evlist);
> > --
> > 2.32.0
> >

--
Cheers,
Changbin Du

\
 
 \ /
  Last update: 2022-01-27 14:20    [W:0.043 / U:0.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site