[RFC][PATCH] perf config: reimplement perf_config() using perf_config_set__iter()

From: Taeung Song
Date: Tue May 17 2016 - 11:52:22 EST


Everytime perf_config() is called, perf_config() always read config files.
(i.e. user config '~/.perfconfig' and system config '$(sysconfdir)/perfconfig')

But we need to use 'struct perf_config_set config_set'
that already contains all config key-value pairs
to avoid this repetitive work in perf_config().

In other words, if new perf_config() is called,
only first time 'config_set' is initialized
collecting all configs from config files and it work with perf_config_set__iter().

If we do, what old perf_config() handle is the same as new perf_config() work
without the repetitive work that read config files.

Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Signed-off-by: Taeung Song <treeze.taeung@xxxxxxxxx>
---
tools/perf/util/config.c | 147 +++++++++++++++++++++++++++++++----------------
1 file changed, 98 insertions(+), 49 deletions(-)

diff --git a/tools/perf/util/config.c b/tools/perf/util/config.c
index dad7d82..27feb58 100644
--- a/tools/perf/util/config.c
+++ b/tools/perf/util/config.c
@@ -28,6 +28,7 @@ static int config_linenr;
static int config_file_eof;

const char *config_exclusive_filename;
+struct perf_config_set *config_set;

static int get_next_char(void)
{
@@ -477,54 +478,6 @@ static int perf_config_global(void)
return !perf_env_bool("PERF_CONFIG_NOGLOBAL", 0);
}

-int perf_config(config_fn_t fn, void *data)
-{
- int ret = 0, found = 0;
- const char *home = NULL;
-
- /* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
- if (config_exclusive_filename)
- return perf_config_from_file(fn, config_exclusive_filename, data);
- if (perf_config_system() && !access(perf_etc_perfconfig(), R_OK)) {
- ret += perf_config_from_file(fn, perf_etc_perfconfig(),
- data);
- found += 1;
- }
-
- home = getenv("HOME");
- if (perf_config_global() && home) {
- char *user_config = strdup(mkpath("%s/.perfconfig", home));
- struct stat st;
-
- if (user_config == NULL) {
- warning("Not enough memory to process %s/.perfconfig, "
- "ignoring it.", home);
- goto out;
- }
-
- if (stat(user_config, &st) < 0)
- goto out_free;
-
- if (st.st_uid && (st.st_uid != geteuid())) {
- warning("File %s not owned by current user or root, "
- "ignoring it.", user_config);
- goto out_free;
- }
-
- if (!st.st_size)
- goto out_free;
-
- ret += perf_config_from_file(fn, user_config, data);
- found += 1;
-out_free:
- free(user_config);
- }
-out:
- if (found == 0)
- return -1;
- return ret;
-}
-
static struct perf_config_section *find_section(struct list_head *sections,
const char *section_name)
{
@@ -645,18 +598,114 @@ out_free:
return -1;
}

+static int perf_config_set__init(struct perf_config_set *set)
+{
+ int ret = 0, found = 0;
+ const char *home = NULL;
+
+ /* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
+ if (config_exclusive_filename)
+ return perf_config_from_file(collect_config, config_exclusive_filename, set);
+ if (perf_config_system() && !access(perf_etc_perfconfig(), R_OK)) {
+ ret += perf_config_from_file(collect_config, perf_etc_perfconfig(), set);
+ found += 1;
+ }
+
+ home = getenv("HOME");
+ if (perf_config_global() && home) {
+ char *user_config = strdup(mkpath("%s/.perfconfig", home));
+ struct stat st;
+
+ if (user_config == NULL) {
+ warning("Not enough memory to process %s/.perfconfig, "
+ "ignoring it.", home);
+ goto out;
+ }
+
+ if (stat(user_config, &st) < 0)
+ goto out_free;
+
+ if (st.st_uid && (st.st_uid != geteuid())) {
+ warning("File %s not owned by current user or root, "
+ "ignoring it.", user_config);
+ goto out_free;
+ }
+
+ if (!st.st_size)
+ goto out_free;
+
+ ret += perf_config_from_file(collect_config, user_config, set);
+ found += 1;
+out_free:
+ free(user_config);
+ }
+out:
+ if (found == 0)
+ return -1;
+ return ret;
+}
+
struct perf_config_set *perf_config_set__new(void)
{
struct perf_config_set *set = zalloc(sizeof(*set));

if (set) {
INIT_LIST_HEAD(&set->sections);
- perf_config(collect_config, set);
+ if (perf_config_set__init(set) < 0)
+ return NULL;
}

return set;
}

+static int perf_config_init(void)
+{
+ if (config_set != NULL)
+ return 0;
+
+ config_set = perf_config_set__new();
+ if (!config_set)
+ return -1;
+
+ return 0;
+}
+
+static int perf_config_set__iter(struct perf_config_set *set, config_fn_t fn, void *data)
+{
+ struct perf_config_section *section;
+ struct perf_config_item *item;
+ struct list_head *sections;
+ char key[BUFSIZ];
+
+ if (set == NULL)
+ return -1;
+
+ sections = &set->sections;
+ if (list_empty(sections))
+ return -1;
+
+ list_for_each_entry(section, sections, node) {
+ list_for_each_entry(item, &section->items, node) {
+ char *value = item->value;
+
+ if (value) {
+ scnprintf(key, sizeof(key), "%s.%s",
+ section->name, item->name);
+ fn(key, value, data);
+ }
+ }
+ }
+
+ return 0;
+}
+
+int perf_config(config_fn_t fn, void *data)
+{
+ if (perf_config_init() < 0)
+ return -1;
+ return perf_config_set__iter(config_set, fn, data);
+}
+
static void perf_config_item__delete(struct perf_config_item *item)
{
zfree(&item->name);
--
2.5.0