[PATCH v1 1/8] perf report: Improve error msg when no first/last sample time found

[Jin Yao]

The following message will be returned to user when executing
'perf report --time' if perf data file doesn't contain the
first/last sample time.

"HINT: no first/last sample time found in perf data.
 Please use latest perf binary to execute 'perf record'
 (if '--buildid-all' is enabled, needs to set '--timestamp-boundary')."

Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
---
 tools/perf/builtin-report.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index dd4df9a..a6c5cf2 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -1299,7 +1299,9 @@ int cmd_report(int argc, const char **argv)
 	if (perf_time__parse_str(report.ptime_range, report.time_str) != 0) {
 		if (session->evlist->first_sample_time == 0 &&
 		    session->evlist->last_sample_time == 0) {
-			pr_err("No first/last sample time in perf data\n");
+			pr_err("HINT: no first/last sample time found in perf data.\n"
+			       "Please use latest perf binary to execute 'perf record'\n"
+			       "(if '--buildid-all' is enabled, please set '--timestamp-boundary').\n");
 			return -EINVAL;
 		}
 
-- 
2.7.4