perf tools: Add 'perf config' command

The perf configuration file contains many variables to change various
aspects of each of its tools, including output, disk usage, etc.

But looking at the state of configuration is difficult and there's no
documentation about config variables except for the variables in
perfconfig.example exist.

So this patch adds a 'perf-config' command with a '--list' option.

    perf config [options]

    display current perf config variables.
    # perf config -l | --list

Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1447768424-17327-1-git-send-email-treeze.taeung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

5 files changed, 70 insertions, 0 deletions

diff --git a/tools/perf/Build b/tools/perf/Build
index 72237455b400..2c7aaf2ba119 100644
--- a/tools/perf/Build
+++ b/tools/perf/Build
@@ -1,5 +1,6 @@
 perf-y += builtin-bench.o
 perf-y += builtin-annotate.o
+perf-y += builtin-config.o
 perf-y += builtin-diff.o
 perf-y += builtin-evlist.o
 perf-y += builtin-help.o
diff --git a/tools/perf/builtin-config.c b/tools/perf/builtin-config.c
new file mode 100644
index 000000000000..427ea7a705b8
--- /dev/null
+++ b/tools/perf/builtin-config.c
@@ -0,0 +1,66 @@
+/*
+ * builtin-config.c
+ *
+ * Copyright (C) 2015, Taeung Song <treeze.taeung@gmail.com>
+ *
+ */
+#include "builtin.h"
+
+#include "perf.h"
+
+#include "util/cache.h"
+#include "util/parse-options.h"
+#include "util/util.h"
+#include "util/debug.h"
+
+static const char * const config_usage[] = {
+        "perf config [options]",
+        NULL
+};
+
+enum actions {
+        ACTION_LIST = 1
+} actions;
+
+static struct option config_options[] = {
+        OPT_SET_UINT('l', "list", &actions,
+                     "show current config variables", ACTION_LIST),
+        OPT_END()
+};
+
+static int show_config(const char *key, const char *value,
+                       void *cb __maybe_unused)
+{
+        if (value)
+                printf("%s=%s\n", key, value);
+        else
+                printf("%s\n", key);
+
+        return 0;
+}
+
+int cmd_config(int argc, const char **argv, const char *prefix __maybe_unused)
+{
+        int ret = 0;
+
+        argc = parse_options(argc, argv, config_options, config_usage,
+                             PARSE_OPT_STOP_AT_NON_OPTION);
+
+        switch (actions) {
+        case ACTION_LIST:
+                if (argc) {
+                        pr_err("Error: takes no arguments\n");
+                        parse_options_usage(config_usage, config_options, "l", 1);
+                } else {
+                        ret = perf_config(show_config, NULL);
+                        if (ret < 0)
+                                pr_err("Nothing configured, "
+                                       "please check your ~/.perfconfig file\n");
+                }
+                break;
+        default:
+                usage_with_options(config_usage, config_options);
+        }
+
+        return ret;
+}
diff --git a/tools/perf/builtin.h b/tools/perf/builtin.h
index 3688ad29085f..3f871b54e261 100644
--- a/tools/perf/builtin.h
+++ b/tools/perf/builtin.h
@@ -17,6 +17,7 @@ extern int cmd_annotate(int argc, const char **argv, const char *prefix);
 extern int cmd_bench(int argc, const char **argv, const char *prefix);
 extern int cmd_buildid_cache(int argc, const char **argv, const char *prefix);
 extern int cmd_buildid_list(int argc, const char **argv, const char *prefix);
+extern int cmd_config(int argc, const char **argv, const char *prefix);
 extern int cmd_diff(int argc, const char **argv, const char *prefix);
 extern int cmd_evlist(int argc, const char **argv, const char *prefix);
 extern int cmd_help(int argc, const char **argv, const char *prefix);
diff --git a/tools/perf/command-list.txt b/tools/perf/command-list.txt
index 00fcaf8a5b8d..acc3ea7d90b7 100644
--- a/tools/perf/command-list.txt
+++ b/tools/perf/command-list.txt
@@ -9,6 +9,7 @@ perf-buildid-cache		mainporcelain common
 perf-buildid-list               mainporcelain common
 perf-data                       mainporcelain common
 perf-diff                       mainporcelain common
+perf-config                     mainporcelain common
 perf-evlist                     mainporcelain common
 perf-inject                     mainporcelain common
 perf-kmem                       mainporcelain common
diff --git a/tools/perf/perf.c b/tools/perf/perf.c
index 3d4c7c09adea..4bee53c3f796 100644
--- a/tools/perf/perf.c
+++ b/tools/perf/perf.c
@@ -39,6 +39,7 @@ struct cmd_struct {
 static struct cmd_struct commands[] = {
         { "buildid-cache", cmd_buildid_cache, 0 },
         { "buildid-list", cmd_buildid_list, 0 },
+        { "config",     cmd_config,     0 },
         { "diff",       cmd_diff,       0 },
         { "evlist",     cmd_evlist,     0 },
         { "help",       cmd_help,       0 },