diff options
Diffstat (limited to 'tools/perf/util/evlist.c')
| -rw-r--r-- | tools/perf/util/evlist.c | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 6737420891cd..0b5425b4d8d6 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -1153,3 +1153,39 @@ int perf_evlist__strerror_tp(struct perf_evlist *evlist __maybe_unused, return 0; } + +int perf_evlist__strerror_open(struct perf_evlist *evlist __maybe_unused, + int err, char *buf, size_t size) +{ + int printed, value; + char sbuf[128], *emsg = strerror_r(err, sbuf, sizeof(sbuf)); + + switch (err) { + case EACCES: + case EPERM: + printed = scnprintf(buf, size, + "Error:\t%s.\n" + "Hint:\tCheck /proc/sys/kernel/perf_event_paranoid setting.", emsg); + + if (filename__read_int("/proc/sys/kernel/perf_event_paranoid", &value)) + break; + + printed += scnprintf(buf + printed, size - printed, "\nHint:\t"); + + if (value >= 2) { + printed += scnprintf(buf + printed, size - printed, + "For your workloads it needs to be <= 1\nHint:\t"); + } + printed += scnprintf(buf + printed, size - printed, + "For system wide tracing it needs to be set to -1"); + + printed += scnprintf(buf + printed, size - printed, + ".\nHint:\tThe current value is %d.", value); + break; + default: + scnprintf(buf, size, "%s", emsg); + break; + } + + return 0; +} |