Em Thu, Jan 26, 2017 at 06:35:38PM +0900, Taeung Song escreveu:
> Currently perf ftrace command will select 'function_graph' or 'function'.
> So add ftrace.tracer config option to select tracer
>
> # cat ~/.perfconfig
> [ftrace]
> tracer = function
>
> # perf ftrace usleep 123456 | head -10
> <...>-14450 [002] d... 10089.284231: finish_task_switch <-__schedule
> <...>-14450 [002] .... 10089.284232: finish_wait <-pipe_wait
> <...>-14450 [002] .... 10089.284232: mutex_lock <-pipe_wait
> <...>-14450 [002] .... 10089.284232: _cond_resched <-mutex_lock
> <...>-14450 [002] .... 10089.284233: generic_pipe_buf_confirm
> <-pipe_read
>
> Cc: Jiri Olsa <[email protected]>
> Cc: Namhyung Kim <[email protected]>
> Signed-off-by: Taeung Song <[email protected]>
> ---
> tools/perf/builtin-ftrace.c | 20 ++++++++++++++++++++
> 1 file changed, 20 insertions(+)
>
> diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
> index 414444d..8df5416 100644
> --- a/tools/perf/builtin-ftrace.c
> +++ b/tools/perf/builtin-ftrace.c
> @@ -17,6 +17,7 @@
> #include "evlist.h"
> #include "target.h"
> #include "thread_map.h"
> +#include "util/config.h"
>
>
> #define DEFAULT_TRACER "function_graph"
> @@ -198,6 +199,23 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace, int
> argc, const char **argv)
> return done ? 0 : -1;
> }
>
> +static int perf_ftrace_config(const char *var, const char *value, void *cb)
> +{
> + struct perf_ftrace *ftrace = cb;
> +
> + if (!strcmp(var, "ftrace.tracer")) {
> + if (!strcmp(value, "function_graph"))
> + ftrace->tracer = DEFAULT_TRACER;
> + else if (!strcmp(value, "function"))
> + ftrace->tracer = "function";
> + else
> + return -1;
Please warn the user for invalid values and either just say that it is
ignoring that setting or return -1 to make perf_config() return that,
then make cmd_ftrace() check the return of perf_config() and bail out if
you're not ignoring the config value.
I think its better to do a: "pr_err()" in that "return -1" branch and
make 'perf ftrace' fail, so that the user can fix its config before
proceeding.
- Arnaldo
> + return 0;
> + }
> +
> + return 0;
> +}
> +
> int cmd_ftrace(int argc, const char **argv, const char *prefix
> __maybe_unused)
> {
> int ret;
> @@ -218,6 +236,8 @@ int cmd_ftrace(int argc, const char **argv, const char
> *prefix __maybe_unused)
> OPT_END()
> };
>
> + perf_config(perf_ftrace_config, &ftrace);
> +
> argc = parse_options(argc, argv, ftrace_options, ftrace_usage,
> PARSE_OPT_STOP_AT_NON_OPTION);
> if (!argc)
> --
> 2.7.4
