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, 5 insertions, 29 deletions

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 8d41d0b58956..f5fd260f7b20 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -892,7 +892,7 @@ static void perf_top__mmap_read(struct perf_top *top)
 
 static void perf_top__start_counters(struct perf_top *top)
 {
-        char msg[128];
+        char msg[512];
         struct perf_evsel *counter;
         struct perf_evlist *evlist = top->evlist;
         struct perf_record_opts *opts = &top->record_opts;
@@ -900,42 +900,18 @@ static void perf_top__start_counters(struct perf_top *top)
         perf_evlist__config(evlist, opts);
 
         list_for_each_entry(counter, &evlist->entries, node) {
-                struct perf_event_attr *attr = &counter->attr;
 try_again:
                 if (perf_evsel__open(counter, top->evlist->cpus,
                                      top->evlist->threads) < 0) {
-                        int err = errno;
-
-                        if (err == EPERM || err == EACCES) {
-                                ui__error_paranoid();
-                                goto out_err;
-                        }
-
-                        if (perf_evsel__fallback(counter, err, msg, sizeof(msg))) {
+                        if (perf_evsel__fallback(counter, errno, msg, sizeof(msg))) {
                                 if (verbose)
                                         ui__warning("%s\n", msg);
                                 goto try_again;
                         }
 
-                        if (err == ENOENT) {
-                                ui__error("The %s event is not supported.\n",
-                                          perf_evsel__name(counter));
-                                goto out_err;
-                        } else if (err == EMFILE) {
-                                ui__error("Too many events are opened.\n"
-                                            "Try again after reducing the number of events\n");
-                                goto out_err;
-                        } else if ((err == EOPNOTSUPP) && (attr->precise_ip)) {
-                                ui__error("\'precise\' request may not be supported. "
-                                          "Try removing 'p' modifier\n");
-                                goto out_err;
-                        }
-
-                        ui__error("The sys_perf_event_open() syscall "
-                                    "returned with %d (%s).  /bin/dmesg "
-                                    "may provide additional information.\n"
-                                    "No CONFIG_PERF_EVENTS=y kernel support "
-                                    "configured?\n", err, strerror(err));
+                        perf_evsel__open_strerror(counter, &opts->target,
+                                                  errno, msg, sizeof(msg));
+                        ui__error("%s\n", msg);
                         goto out_err;
                 }
         }