[PATCH] perf evsel: Update the hint for the usage of the load latency event

From: kan . liang
Date: Wed Aug 17 2022 - 08:41:31 EST


From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>

The current message is not providing enough information. It's hard for
a user to figure out what's the auxiliary event.

Adding the event name of the auxiliary event in the hint. The user can
simply cut & paste.

Suggested-by: Stephane Eranian <eranian@xxxxxxxxxx>
Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
---
tools/perf/util/evsel.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 4852089e1d79..0d1bb5c723e9 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -3056,7 +3056,8 @@ int evsel__open_strerror(struct evsel *evsel, struct target *target,
break;
case ENODATA:
return scnprintf(msg, size, "Cannot collect data source with the load latency event alone. "
- "Please add an auxiliary event in front of the load latency event.");
+ "Please add an auxiliary event in front of the load latency event. "
+ "For example, -e {mem-loads-aux,%s}.", evsel__name(evsel));
default:
break;
}
--
2.35.1