Re: [PATCH] perf script: Fix display inconsitency when call-graph config is used

Hekuang
2016-05-27T03:49:04Z

ping..

在 2016/5/16 12:51, He Kuang 写道:
> There's a display inconsistency when 'call-graph' config event appears
> in different position. The problem can be reproduced like this:
>
> We record signal_deliver with call-graph and signal_generate without it.
>
> $ perf record -g -a -e signal:signal_deliver -e signal:signal_generate/call-graph=no/
>
> [ perf record: Captured and wrote 0.017 MB perf.data (2 samples) ]
>
> $ perf script
>
> kworker/u2:1 13 [000] 6563.875949: signal:signal_generate: sig=2 errno=0 code=128 comm=perf pid=1313 grp=1 res=0 ff61cc __send_signal+0x3ec ([kernel.kallsyms])
> perf 1313 [000] 6563.877584: signal:signal_deliver: sig=2 errno=0 code=128 sa_handler=43115e sa_flags=14000000
> 7ffff314 get_signal+0x80007f0023a4 ([kernel.kallsyms])
> 7fffe358 do_signal+0x80007f002028 ([kernel.kallsyms])
> 7fffa5e8 exit_to_usermode_loop+0x80007f002053 ([kernel.kallsyms])
> ...
>
> Then we exchange the order of these two events in commandline, and keep
> signal_generate without call-graph.
>
> $ perf record -g -a -e signal:signal_generate/call-graph=no/ -e signal:signal_deliver
>
> [ perf record: Captured and wrote 0.017 MB perf.data (2 samples) ]
>
> $ perf script
>
> kworker/u2:2 1314 [000] 6933.353060: signal:signal_generate: sig=2 errno=0 code=128 comm=perf pid=1321 grp=1 res=0
> perf 1321 [000] 6933.353872: signal:signal_deliver: sig=2 errno=0 code=128 sa_handler=43115e sa_flags=14000000
>
> This time, the callchain of the event signal_deliver disappeared. The
> problem is caused by that perf only checks for the first evsel in evlist
> and decides if callchain should be printed.
>
> This patch travseres all evsels in evlist to see if any of them have
> callchains, and shows the right result:
>
> $ perf script
>
> kworker/u2:2 1314 [000] 6933.353060: signal:signal_generate: sig=2 errno=0 code=128 comm=perf pid=1321 grp=1 res=0 ff61cc __send_signal+0x3ec ([kernel.kallsyms])
> perf 1321 [000] 6933.353872: signal:signal_deliver: sig=2 errno=0 code=128 sa_handler=43115e sa_flags=14000000
> 7ffff314 get_signal+0x80007f0023a4 ([kernel.kallsyms])
> 7fffe358 do_signal+0x80007f002028 ([kernel.kallsyms])
> 7fffa5e8 exit_to_usermode_loop+0x80007f002053 ([kernel.kallsyms])
> ...
>
> Signed-off-by: He Kuang <hekuang@huawei.com>
> ---
> tools/perf/builtin-script.c | 23 +++++++++++++----------
> 1 file changed, 13 insertions(+), 10 deletions(-)
>
> diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
> index efca816..7a18b92 100644
> --- a/tools/perf/builtin-script.c
> +++ b/tools/perf/builtin-script.c
> @@ -339,7 +339,7 @@ static void set_print_ip_opts(struct perf_event_attr *attr)
> */
> static int perf_session__check_output_opt(struct perf_session *session)
> {
> - int j;
> + unsigned int j;
> struct perf_evsel *evsel;
>
> for (j = 0; j < PERF_TYPE_MAX; ++j) {
> @@ -388,17 +388,20 @@ static int perf_session__check_output_opt(struct perf_session *session)
> struct perf_event_attr *attr;
>
> j = PERF_TYPE_TRACEPOINT;
> - evsel = perf_session__find_first_evtype(session, j);
> - if (evsel == NULL)
> - goto out;
>
> - attr = &evsel->attr;
> + evlist__for_each(session->evlist, evsel) {
> + if (evsel->attr.type != j)
> + continue;
> +
> + attr = &evsel->attr;
>
> - if (attr->sample_type & PERF_SAMPLE_CALLCHAIN) {
> - output[j].fields |= PERF_OUTPUT_IP;
> - output[j].fields |= PERF_OUTPUT_SYM;
> - output[j].fields |= PERF_OUTPUT_DSO;
> - set_print_ip_opts(attr);
> + if (attr->sample_type & PERF_SAMPLE_CALLCHAIN) {
> + output[j].fields |= PERF_OUTPUT_IP;
> + output[j].fields |= PERF_OUTPUT_SYM;
> + output[j].fields |= PERF_OUTPUT_DSO;
> + set_print_ip_opts(attr);
> + goto out;
> + }
> }
> }
>