perf config: Bring perf_default_config to the very beginning at main()

Before this patch each subcommand calls perf_config() by themself,
reading the default configuration together with subcommand specific
options. If a subcommand doesn't have it own options, it needs to call
'perf_config(perf_default_config, NULL)' to ensure .perfconfig is
loaded.

This patch brings perf_config(perf_default_config, NULL) to the very
start of main(), so subcommands don't need to do it.

After this patch, 'llvm.clang-path' works for 'perf trace'.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Suggested-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1456479154-136027-4-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/tools/perf/util/help-unknown-cmd.c b/tools/perf/util/help-unknown-cmd.c
index dc1e41c9b054..43a98a4dc1e1 100644
--- a/tools/perf/util/help-unknown-cmd.c
+++ b/tools/perf/util/help-unknown-cmd.c
@@ -6,7 +6,8 @@
 static int autocorrect;
 static struct cmdnames aliases;
 
-static int perf_unknown_cmd_config(const char *var, const char *value, void *cb)
+static int perf_unknown_cmd_config(const char *var, const char *value,
+                                   void *cb __maybe_unused)
 {
         if (!strcmp(var, "help.autocorrect"))
                 autocorrect = perf_config_int(var,value);
@@ -14,7 +15,7 @@ static int perf_unknown_cmd_config(const char *var, const char *value, void *cb)
         if (!prefixcmp(var, "alias."))
                 add_cmdname(&aliases, var + 6, strlen(var + 6));
 
-        return perf_default_config(var, value, cb);
+        return 0;
 }
 
 static int levenshtein_compare(const void *p1, const void *p2)