perf stat: Fail more clearly when an invalid modifier is specified
Currently we fail without printing any error message on "perf stat -e task-clock-msecs".
The reason is that the task-clock event is matched and the "-msecs" postfix is assumed
to be an event modifier - but is not recognized.
This patch changes the code to be more informative:
$ perf stat -e task-clock-msecs true
invalid event modifier: '-msecs'
Run 'perf list' for a list of valid events and modifiers
And restructures the return value of parse_event_modifier() to allow
the printing of all variants of invalid event modifiers.
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-wlaw3dvz1ly6wple8l52cfca@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 8e54bdb..b686269 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -721,15 +721,19 @@
return EVT_FAILED;
}
-static enum event_result
+static int
parse_event_modifier(const char **strp, struct perf_event_attr *attr)
{
const char *str = *strp;
int exclude = 0;
int eu = 0, ek = 0, eh = 0, precise = 0;
- if (*str++ != ':')
+ if (!*str)
return 0;
+
+ if (*str++ != ':')
+ return -1;
+
while (*str) {
if (*str == 'u') {
if (!exclude)
@@ -750,14 +754,16 @@
++str;
}
- if (str >= *strp + 2) {
- *strp = str;
- attr->exclude_user = eu;
- attr->exclude_kernel = ek;
- attr->exclude_hv = eh;
- attr->precise_ip = precise;
- return 1;
- }
+ if (str < *strp + 2)
+ return -1;
+
+ *strp = str;
+
+ attr->exclude_user = eu;
+ attr->exclude_kernel = ek;
+ attr->exclude_hv = eh;
+ attr->precise_ip = precise;
+
return 0;
}
@@ -800,7 +806,12 @@
return EVT_FAILED;
modifier:
- parse_event_modifier(str, attr);
+ if (parse_event_modifier(str, attr) < 0) {
+ fprintf(stderr, "invalid event modifier: '%s'\n", *str);
+ fprintf(stderr, "Run 'perf list' for a list of valid events and modifiers\n");
+
+ return EVT_FAILED;
+ }
return ret;
}