Commit-ID: c45628b0a3f90c4ffeca5f72f227008ceedc21c5 Gitweb: http://git.kernel.org/tip/c45628b0a3f90c4ffeca5f72f227008ceedc21c5 Author: Wang Nan <[email protected]> AuthorDate: Tue, 24 May 2016 02:28:59 +0000 Committer: Arnaldo Carvalho de Melo <[email protected]> CommitDate: Mon, 30 May 2016 12:41:44 -0300
perf record: Robustify perf_event__synth_time_conv() It is possible that all events in an evlist are overwritable. perf_event__synth_time_conv() should not crash in this case. record__pick_pc() is used to check avaliability. Signed-off-by: Wang Nan <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Masami Hiramatsu <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Zefan Li <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: He Kuang <[email protected]> [ Split from a larger patch ] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> --- tools/perf/arch/x86/util/tsc.c | 2 ++ tools/perf/builtin-record.c | 9 ++++++++- 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/tools/perf/arch/x86/util/tsc.c b/tools/perf/arch/x86/util/tsc.c index 357f1b1..2e5567c 100644 --- a/tools/perf/arch/x86/util/tsc.c +++ b/tools/perf/arch/x86/util/tsc.c @@ -62,6 +62,8 @@ int perf_event__synth_time_conv(const struct perf_event_mmap_page *pc, struct perf_tsc_conversion tc; int err; + if (!pc) + return 0; err = perf_read_tsc_conversion(pc, &tc); if (err == -EOPNOTSUPP) return 0; diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index dc3fcb5..d4cf1b0 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -655,6 +655,13 @@ perf_event__synth_time_conv(const struct perf_event_mmap_page *pc __maybe_unused return 0; } +static const struct perf_event_mmap_page *record__pick_pc(struct record *rec) +{ + if (rec->evlist && rec->evlist->mmap && rec->evlist->mmap[0].base) + return rec->evlist->mmap[0].base; + return NULL; +} + static int record__synthesize(struct record *rec) { struct perf_session *session = rec->session; @@ -692,7 +699,7 @@ static int record__synthesize(struct record *rec) } } - err = perf_event__synth_time_conv(rec->evlist->mmap[0].base, tool, + err = perf_event__synth_time_conv(record__pick_pc(rec), tool, process_synthesized_event, machine); if (err) goto out;
