[PATCH 20/44] perf config: Allow creating empty config set for config file autogeneration

From: Arnaldo Carvalho de Melo
Date: Fri Sep 22 2017 - 10:44:17 EST

From: Taeung Song <treeze.taeung@xxxxxxxxx>

When there isn't a config file (e.g. ~/.perfconfig) or it has nothing,
the config set wasn't created.

If the config set does not exist, a config file can't be autogenerated.

So allow creating a empty config set in the above case,
then we can support the config file autogeneration.


$ rm -f ~/.perfconfig
$ perf config --user report.children=false

$ cat ~/.perfconfig
cat: /root/.perfconfig: No such file or directory

But I think it should work even if there isn't a config file.


$ rm -f ~/.perfconfig
$ perf config --user report.children=false

$ cat ~/.perfconfig
# this file is auto-generated.
children = false


As a result, if perf_config_set__init() fails, it looks as if the config
set isn't freed. But it isn't a problem. Because the config set will be
freed by perf_config_set__delete() at the end of cmd_config().

Signed-off-by: Taeung Song <treeze.taeung@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/1504754336-9824-1-git-send-email-treeze.taeung@xxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
tools/perf/util/config.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/tools/perf/util/config.c b/tools/perf/util/config.c
index bc75596f9e79..d2b6983b1779 100644
--- a/tools/perf/util/config.c
+++ b/tools/perf/util/config.c
@@ -700,10 +700,7 @@ struct perf_config_set *perf_config_set__new(void)

if (set) {
- if (perf_config_set__init(set) < 0) {
- perf_config_set__delete(set);
- set = NULL;
- }
+ perf_config_set__init(set);

return set;