Re: [PATCH 08/19] perf ftrace: add option -l/--long-info to show more info

From: Changbin Du
Date: Sat Jun 06 2020 - 10:15:11 EST


On Wed, May 20, 2020 at 06:02:57PM -0300, Arnaldo Carvalho de Melo wrote:
> Em Sun, May 10, 2020 at 11:06:17PM +0800, Changbin Du escreveu:
> > Sometimes we want ftrace display more and longer information about trace.
>
> Humm, -v? Or that would bring too much stuff from other parts of perf?
> I guess so, perhaps as an option to the function-graph tracer, one that
> combines, as you do, several options provided by that tracer?
>
yes, this option enables mutiple trace options onetime, which will make the
function tracer or graph tracer output as much as more information per-line. So I call it
as 'long'.

> - Arnaldo
>
> > $ sudo perf ftrace -G -l
> > 6800.190937 | 4) <...>-7683 | 2.072 us | mutex_unlock();
> > 6800.190941 | 4) <...>-7683 | 2.171 us | __fsnotify_parent();
> > 6800.190943 | 4) <...>-7683 | 1.497 us | fsnotify();
> > 6800.190944 | 4) <...>-7683 | 0.775 us | __sb_end_write();
> > 6800.190945 | 4) <...>-7683 | 0.854 us | fpregs_assert_state_consistent();
> > 6800.190947 | 4) <...>-7683 | | do_syscall_64() {
> > 6800.190948 | 4) <...>-7683 | | __x64_sys_close() {
> > 6800.190948 | 4) <...>-7683 | | __close_fd() {
> > 6800.190948 | 4) <...>-7683 | 0.322 us | _raw_spin_lock();
> > 6800.190949 | 4) <...>-7683 | | filp_close() {
> > 6800.190949 | 4) <...>-7683 | 0.320 us | dnotify_flush();
> > 6800.190950 | 4) <...>-7683 | 0.325 us | locks_remove_posix();
> >
> > Signed-off-by: Changbin Du <changbin.du@xxxxxxxxx>
> > ---
> > tools/perf/builtin-ftrace.c | 28 ++++++++++++++++++++++++++++
> > 1 file changed, 28 insertions(+)
> >
> > diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
> > index b16600a16efa..f11f2d3431b0 100644
> > --- a/tools/perf/builtin-ftrace.c
> > +++ b/tools/perf/builtin-ftrace.c
> > @@ -42,6 +42,7 @@ struct perf_ftrace {
> > bool func_stack_trace;
> > bool nosleep_time;
> > bool nofuncgraph_irqs;
> > + bool long_info;
> > };
> >
> > struct filter_entry {
> > @@ -190,6 +191,9 @@ static void reset_tracing_options(struct perf_ftrace *ftrace __maybe_unused)
> > write_tracing_option_file("func_stack_trace", "0");
> > write_tracing_option_file("sleep-time", "1");
> > write_tracing_option_file("funcgraph-irqs", "1");
> > + write_tracing_option_file("funcgraph-proc", "0");
> > + write_tracing_option_file("funcgraph-abstime", "0");
> > + write_tracing_option_file("irq-info", "0");
> > }
> >
> > static int reset_tracing_files(struct perf_ftrace *ftrace __maybe_unused)
> > @@ -371,6 +375,23 @@ static int set_tracing_funcgraph_irqs(struct perf_ftrace *ftrace)
> > return 0;
> > }
> >
> > +static int set_tracing_long_info(struct perf_ftrace *ftrace)
> > +{
> > + if (!ftrace->long_info)
> > + return 0;
> > +
> > + if (write_tracing_option_file("funcgraph-proc", "1") < 0)
> > + return -1;
> > +
> > + if (write_tracing_option_file("funcgraph-abstime", "1") < 0)
> > + return -1;
> > +
> > + if (write_tracing_option_file("irq-info", "1") < 0)
> > + return -1;
> > +
> > + return 0;
> > +}
> > +
> > static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv)
> > {
> > char *trace_file;
> > @@ -449,6 +470,11 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv)
> > goto out_reset;
> > }
> >
> > + if (set_tracing_long_info(ftrace) < 0) {
> > + pr_err("failed to set tracing option funcgraph-proc/funcgraph-abstime/irq-info\n");
> > + goto out_reset;
> > + }
> > +
> > if (write_tracing_file("current_tracer", ftrace->tracer) < 0) {
> > pr_err("failed to set current_tracer to %s\n", ftrace->tracer);
> > goto out_reset;
> > @@ -588,6 +614,8 @@ int cmd_ftrace(int argc, const char **argv)
> > "Measure on-CPU time only (function_graph only)"),
> > OPT_BOOLEAN(0, "nofuncgraph-irqs", &ftrace.nofuncgraph_irqs,
> > "Ignore functions that happen inside interrupt (function_graph only)"),
> > + OPT_BOOLEAN('l', "long-info", &ftrace.long_info,
> > + "Show process names, PIDs, timestamps, irq-info if available"),
> > OPT_END()
> > };
> >
> > --
> > 2.25.1
> >
>
> --
>
> - Arnaldo

--
Cheers,
Changbin Du