perf evsel: Introduce perf_evsel__open_strerror method

That consolidates the error messages in 'record', 'stat' and 'top', that
now get a consistent set of messages and allow other tools to use the
new method to report problems using whatever UI toolkit.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-1cudb7wl996kz7ilz83ctvhr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 49 insertions, 0 deletions

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 0c88e5c12dab..e45332d08a58 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1406,3 +1406,52 @@ bool perf_evsel__fallback(struct perf_evsel *evsel, int err,
 
         return false;
 }
+
+int perf_evsel__open_strerror(struct perf_evsel *evsel,
+                              struct perf_target *target,
+                              int err, char *msg, size_t size)
+{
+        switch (err) {
+        case EPERM:
+        case EACCES:
+                return scnprintf(msg, size, "%s",
+                 "You may not have permission to collect %sstats.\n"
+                 "Consider tweaking /proc/sys/kernel/perf_event_paranoid:\n"
+                 " -1 - Not paranoid at all\n"
+                 "  0 - Disallow raw tracepoint access for unpriv\n"
+                 "  1 - Disallow cpu events for unpriv\n"
+                 "  2 - Disallow kernel profiling for unpriv",
+                                 target->system_wide ? "system-wide " : "");
+        case ENOENT:
+                return scnprintf(msg, size, "The %s event is not supported.",
+                                 perf_evsel__name(evsel));
+        case EMFILE:
+                return scnprintf(msg, size, "%s",
+                         "Too many events are opened.\n"
+                         "Try again after reducing the number of events.");
+        case ENODEV:
+                if (target->cpu_list)
+                        return scnprintf(msg, size, "%s",
+         "No such device - did you specify an out-of-range profile CPU?\n");
+                break;
+        case EOPNOTSUPP:
+                if (evsel->attr.precise_ip)
+                        return scnprintf(msg, size, "%s",
+        "\'precise\' request may not be supported. Try removing 'p' modifier.");
+#if defined(__i386__) || defined(__x86_64__)
+                if (evsel->attr.type == PERF_TYPE_HARDWARE)
+                        return scnprintf(msg, size, "%s",
+        "No hardware sampling interrupt available.\n"
+        "No APIC? If so then you can boot the kernel with the \"lapic\" boot parameter to force-enable it.");
+#endif
+                break;
+        default:
+                break;
+        }
+
+        return scnprintf(msg, size,
+        "The sys_perf_event_open() syscall returned with %d (%s) for event (%s).  \n"
+        "/bin/dmesg may provide additional information.\n"
+        "No CONFIG_PERF_EVENTS=y kernel support configured?\n",
+                         err, strerror(err), perf_evsel__name(evsel));
+}