ping. 在 2016/8/4 19:25, He Kuang 写道:
Because perf data from pipe do not have a header with evsel attr, we should not check that and disable symbol_conf.use_callchain. Otherwise, perf script won't show callchains even if the data stream contains callchain.Before: $ perf record -g -o - uname |perf script Linux [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.000 MB - ] uname 1828 182630.186578: 250000 cpu-clock: ..b9499 setup_arg_pages uname 1828 182630.186850: 250000 cpu-clock: ..83b20 ___might_sleep uname 1828 182630.187153: 250000 cpu-clock: ..4b6be file_map_prot_ch ... After: $ perf record -g -o - uname |perf script Linux [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.000 MB - ] uname 1833 182675.927099: 250000 cpu-clock: ba5520 _raw_spin_lock+0xfe200040 ([kernel.kallsyms]) 389dd4 expand_downwards+0xfe200154 ([kernel.kallsyms]) 389f34 expand_stack+0xfe200024 ([kernel.kallsyms]) 3b957e setup_arg_pages+0xfe20019e ([kernel.kallsyms]) 40c80f load_elf_binary+0xfe20042f ([kernel.kallsyms]) ... Signed-off-by: He Kuang <[email protected]> --- tools/perf/builtin-script.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c index d47aef9..ec8df8f 100644 --- a/tools/perf/builtin-script.c +++ b/tools/perf/builtin-script.c @@ -371,14 +371,16 @@ static int perf_session__check_output_opt(struct perf_session *session)if (!no_callchain) {bool use_callchain = false; + bool not_pipe = false;evlist__for_each_entry(session->evlist, evsel) {+ not_pipe = true; if (evsel->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { use_callchain = true; break; } } - if (!use_callchain) + if (not_pipe && !use_callchain) symbol_conf.use_callchain = false; }

