perf test vmlinux: Avoid printing headers for empty lists

Before:

  # perf test -F -v 1
   1: vmlinux symtab matches kallsyms:
  --- start ---
<SNIP>
  WARN: Maps only in vmlinux:
   ffffffffb7d7d000-ffffffffb7eeaac8 117d000 [kernel].init.text
   ffffffffb7eeaac8-ffffffffc03ad000 12eaac8 [kernel].exit.text
  WARN: Maps in vmlinux with a different name in kallsyms:
  WARN: Maps only in kallsyms:
  ---- end ----
  vmlinux symtab matches kallsyms: Ok
  #

The two last WARN lines are now suppressed, since there are no such
cases detected.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-9ww8uvzl682ykaw8ht1tozlr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/tests/vmlinux-kallsyms.c b/tools/perf/tests/vmlinux-kallsyms.c
index 6bd5bf980de25531a57c5eb4a444af33a36cb14c..450f69960931bb6777c6288acb81da2ac8cb523f 100644 (file)
--- a/tools/perf/tests/vmlinux-kallsyms.c
+++ b/tools/perf/tests/vmlinux-kallsyms.c
@@ -28,6 +28,7 @@ int test__vmlinux_matches_kallsyms(int subtest __maybe_unused)
        enum map_type type = MAP__FUNCTION;
        struct maps *maps = &vmlinux.kmaps.maps[type];
        u64 mem_start, mem_end;
+       bool header_printed;
 
        /*
         * Step 1:
@@ -178,7 +179,7 @@ next_pair:
        if (!verbose)
                goto out;
 
-       pr_info("WARN: Maps only in vmlinux:\n");
+       header_printed = false;
 
        for (map = maps__first(maps); map; map = map__next(map)) {
                struct map *
@@ -192,13 +193,18 @@ next_pair:
                                                (map->dso->kernel ?
                                                        map->dso->short_name :
                                                        map->dso->name));
-               if (pair)
+               if (pair) {
                        pair->priv = 1;
-               else
+               } else {
+                       if (!header_printed) {
+                               pr_info("WARN: Maps only in vmlinux:\n");
+                               header_printed = true;
+                       }
                        map__fprintf(map, stderr);
+               }
        }
 
-       pr_info("WARN: Maps in vmlinux with a different name in kallsyms:\n");
+       header_printed = false;
 
        for (map = maps__first(maps); map; map = map__next(map)) {
                struct map *pair;
@@ -211,7 +217,11 @@ next_pair:
                        continue;
 
                if (pair->start == mem_start) {
-                       pair->priv = 1;
+                       if (!header_printed) {
+                               pr_info("WARN: Maps in vmlinux with a different name in kallsyms:\n");
+                               header_printed = true;
+                       }
+
                        pr_info("WARN: %" PRIx64 "-%" PRIx64 " %" PRIx64 " %s in kallsyms as",
                                map->start, map->end, map->pgoff, map->dso->name);
                        if (mem_end != pair->end)
@@ -222,13 +232,18 @@ next_pair:
                }
        }
 
-       pr_info("WARN: Maps only in kallsyms:\n");
+       header_printed = false;
 
        maps = &kallsyms.kmaps.maps[type];
 
        for (map = maps__first(maps); map; map = map__next(map)) {
-               if (!map->priv)
+               if (!map->priv) {
+                       if (!header_printed) {
+                               pr_info("WARN: Maps only in kallsyms:\n");
+                               header_printed = true;
+                       }
                        map__fprintf(map, stderr);
+               }
        }
 out:
        machine__exit(&kallsyms);