Messages in this thread | | | Date | Wed, 20 May 2020 17:58:01 -0300 | From | Arnaldo Carvalho de Melo <> | Subject | Re: [PATCH 04/19] perf ftrace: add support for tracing option 'func_stack_trace' |
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Em Sun, May 10, 2020 at 11:06:13PM +0800, Changbin Du escreveu: > This adds support to display call trace for function tracer. To do this, > just specify a '-s' option. > > $ sudo perf ftrace -T vfs_read -s > iio-sensor-prox-855 [003] 6168.369657: vfs_read <-ksys_read > iio-sensor-prox-855 [003] 6168.369677: <stack trace> > => vfs_read > => ksys_read > => __x64_sys_read > => do_syscall_64 > => entry_SYSCALL_64_after_hwframe > ...
So, for the reason stated in my response to the patch 03/19, I think we should start here with --call-graph for this, instead of --func-stack-trace. And for now don't provide a one-letter equivalent.
- Arnaldo
> Signed-off-by: Changbin Du <changbin.du@gmail.com> > --- > tools/perf/builtin-ftrace.c | 38 +++++++++++++++++++++++++++++++++++++ > 1 file changed, 38 insertions(+) > > diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c > index 57e656c35d28..1d30c2d5f88b 100644 > --- a/tools/perf/builtin-ftrace.c > +++ b/tools/perf/builtin-ftrace.c > @@ -38,6 +38,7 @@ struct perf_ftrace { > struct list_head graph_funcs; > struct list_head nograph_funcs; > int graph_depth; > + bool func_stack_trace; > }; > > struct filter_entry { > @@ -128,9 +129,27 @@ static int append_tracing_file(const char *name, const char *val) > return __write_tracing_file(name, val, true); > } > > +static int write_tracing_option_file(const char *name, const char *val) > +{ > + char *file; > + int ret; > + > + if (asprintf(&file, "options/%s", name) < 0) > + return -1; > + > + ret = __write_tracing_file(file, val, false); > + free(file); > + return ret; > +} > + > static int reset_tracing_cpu(void); > static void reset_tracing_filters(void); > > +static void reset_tracing_options(struct perf_ftrace *ftrace __maybe_unused) > +{ > + write_tracing_option_file("func_stack_trace", "0"); > +} > + > static int reset_tracing_files(struct perf_ftrace *ftrace __maybe_unused) > { > if (write_tracing_file("tracing_on", "0") < 0) > @@ -149,6 +168,7 @@ static int reset_tracing_files(struct perf_ftrace *ftrace __maybe_unused) > return -1; > > reset_tracing_filters(); > + reset_tracing_options(ftrace); > return 0; > } > > @@ -204,6 +224,17 @@ static int set_tracing_cpu(struct perf_ftrace *ftrace) > return set_tracing_cpumask(cpumap); > } > > +static int set_tracing_func_stack_trace(struct perf_ftrace *ftrace) > +{ > + if (!ftrace->func_stack_trace) > + return 0; > + > + if (write_tracing_option_file("func_stack_trace", "1") < 0) > + return -1; > + > + return 0; > +} > + > static int reset_tracing_cpu(void) > { > struct perf_cpu_map *cpumap = perf_cpu_map__new(NULL); > @@ -326,6 +357,11 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv) > goto out_reset; > } > > + if (set_tracing_func_stack_trace(ftrace) < 0) { > + pr_err("failed to set tracing option func_stack_trace\n"); > + goto out_reset; > + } > + > if (set_tracing_filters(ftrace) < 0) { > pr_err("failed to set tracing filters\n"); > goto out_reset; > @@ -459,6 +495,8 @@ int cmd_ftrace(int argc, const char **argv) > "trace given functions only", parse_filter_func), > OPT_CALLBACK('N', "notrace-funcs", &ftrace.notrace, "func", > "do not trace given functions", parse_filter_func), > + OPT_BOOLEAN('s', "func-stack-trace", &ftrace.func_stack_trace, > + "Show kernel stack trace for function tracer"), > OPT_CALLBACK_DEFAULT('G', "graph-funcs", &ftrace.graph_funcs, "func", > "Set graph filter on given functions (imply to use function_graph tracer)", > parse_filter_func, "*"), > -- > 2.25.1 >
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- Arnaldo
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