Re: [PATCH 2/4] perf tools: Add functions which can get or set perf config variables.

Jiri Olsa
2015-05-04T08:41:37Z

On Mon, Apr 27, 2015 at 03:34:24PM +0900, Taeung Song wrote:
> This patch consists of functions
> which can get, set specific config variables.
> For the syntax examples,
>
> perf config [options] [section.subkey[=value] ...]

not sure this gets fixed later on, but after applying
up to this patch I've got following error:

>
> display key-value pairs of specific config variables
> # perf config report.queue-size report.children

[jolsa@krava perf]$ ./perf config report.queue-size
invalid key: report.queue-size[jolsa@krava perf]$

>
> set specific config variables
> # perf config report.queue-size=100M report.children=true

[jolsa@krava perf]$ ./perf config report.queue-size=50M
invalid key: report.queue-size=50M[jolsa@krava perf]$

jirka

>
> Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
> ---
> tools/perf/Documentation/perf-config.txt | 2 +
> tools/perf/builtin-config.c | 276 ++++++++++++++++++++++++++++++-
> tools/perf/util/cache.h | 17 ++
> tools/perf/util/config.c | 30 +++-
> 4 files changed, 320 insertions(+), 5 deletions(-)
>
> diff --git a/tools/perf/Documentation/perf-config.txt b/tools/perf/Documentation/perf-config.txt
> index 489c2c6..b2b3321 100644
> --- a/tools/perf/Documentation/perf-config.txt
> +++ b/tools/perf/Documentation/perf-config.txt
> @@ -8,6 +8,8 @@ perf-config - Get and set variables in configuration file.
> SYNOPSIS
> --------
> [verse]
> +'perf config' [section.subkey[=value] ...]
> +or
> 'perf config' -l | --list
>
> DESCRIPTION
> diff --git a/tools/perf/builtin-config.c b/tools/perf/builtin-config.c
> index 9e4ba72..99292f6 100644
> --- a/tools/perf/builtin-config.c
> +++ b/tools/perf/builtin-config.c
> @@ -15,10 +15,14 @@
>
> static struct {
> bool list_action;
> + bool get_action;
> + bool set_action;
> } params;
>
> +struct list_head *sections;
> +
> static const char * const config_usage[] = {
> - "perf config [options]",
> + "perf config [options] [section.subkey[=value] ...]",
> NULL
> };
> static const struct option config_options[] = {
> @@ -27,6 +31,74 @@ static const struct option config_options[] = {
> OPT_END()
> };
>
> +static struct config_section *find_config_section(const char *section_name)
> +{
> + struct config_section *section_node;
> + list_for_each_entry(section_node, sections, list)
> + if (!strcmp(section_node->name, section_name))
> + return section_node;
> +
> + return NULL;
> +}
> +
> +static struct config_element *find_config_element(const char *subkey,
> + struct config_section *section_node)
> +{
> + struct config_element *element_node;
> +
> + list_for_each_entry(element_node, &section_node->element_head, list)
> + if (!strcmp(element_node->subkey, subkey))
> + return element_node;
> +
> + return NULL;
> +}
> +
> +static struct config_section *init_config_section(const char *section_name)
> +{
> + struct config_section *section_node;
> +
> + section_node = zalloc(sizeof(*section_node));
> + if (!section_node)
> + return NULL;
> +
> + INIT_LIST_HEAD(&section_node->element_head);
> + section_node->name = strdup(section_name);
> + if (!section_node->name) {
> + pr_err("%s: strdup failed\n", __func__);
> + free(section_node);
> + return NULL;
> + }
> +
> + return section_node;
> +}
> +
> +static int add_config_element(struct list_head *head,
> + const char *subkey, const char *value)
> +{
> + struct config_element *element_node;
> + element_node = zalloc(sizeof(*element_node));
> + element_node->subkey = strdup(subkey);
> + if (!element_node->subkey) {
> + pr_err("%s: strdup failed\n", __func__);
> + goto out_free;
> + }
> + if (value) {
> + element_node->value = strdup(value);
> + if (!element_node->value) {
> + pr_err("%s: strdup failed\n", __func__);
> + goto out_free;
> + }
> + } else
> + element_node->value = NULL;
> +
> + list_add_tail(&element_node->list, head);
> + return 0;
> +
> +out_free:
> + free(element_node);
> + return -1;
> +}
> +
> static int show_config(const char *key, const char *value,
> void *cb __maybe_unused)
> {
> @@ -38,12 +110,211 @@ static int show_config(const char *key, const char *value,
> return 0;
> }
>
> -int cmd_config(int argc, const char **argv, const char *prefix __maybe_unused)
> +static void find_config(struct config_section **section_node, struct config_element **element_node,
> + const char *given_section_name, const char *given_subkey)
> +{
> + *section_node = find_config_section(given_section_name);
> +
> + if (*section_node != NULL)
> + *element_node = find_config_element(given_subkey, *section_node);
> + else
> + *element_node = NULL;
> +}
> +
> +static int show_spec_config(const char *section_name, const char *subkey,
> + const char *value __maybe_unused)
> +{
> + struct config_section *section_node = NULL;
> + struct config_element *element_node = NULL;
> + char key[BUFSIZ];
> +
> + find_config(&section_node, &element_node, section_name, subkey);
> +
> + if (section_node && element_node) {
> + scnprintf(key, sizeof(key), "%s.%s", section_node->name, element_node->subkey);
> + show_config(key, element_node->value, NULL);
> + } else
> + pr_err("Error: Failed to find the variable.\n");
> +
> + return 0;
> +}
> +
> +static int set_config(const char *section_name, const char *subkey,
> + const char *value)
> +{
> + struct config_section *section_node = NULL;
> + struct config_element *element_node = NULL;
> +
> + find_config(&section_node, &element_node, section_name, subkey);
> +
> + /* if there isn't existent section, add a new section */
> + if (!section_node) {
> + section_node = init_config_section(section_name);
> + if (!section_node)
> + return -1;
> + list_add_tail(&section_node->list, sections);
> + }
> + /* if nothing to replace, add a new element which contains key-value pair. */
> + if (!element_node)
> + return add_config_element(&section_node->element_head, subkey, value);
> + else
> + element_node->value = (char *)value;
> +
> + return 0;
> +}
> +
> +static int set_spec_config(const char *section_name, const char *subkey,
> + const char *value)
> {
> int ret = 0;
> + ret += set_config(section_name, subkey, value);
> + ret += perf_configset_write_in_full();
> +
> + return ret;
> +}
> +
> +static void parse_key(const char *var, const char **section_name, const char **subkey)
> +{
> + char *key = strdup(var);
> +
> + if (!key)
> + die("%s: strdup failed\n", __func__);
> +
> + *section_name = strsep(&key, ".");
> + *subkey = strsep(&key, ".");
> +}
> +
> +static int collect_config(const char *var, const char *value,
> + void *cb __maybe_unused)
> +{
> + struct config_section *section_node;
> + const char *section_name, *subkey;
> +
> + parse_key(var, &section_name, &subkey);
> +
> + section_node = find_config_section(section_name);
> + if (!section_node) {
> + /* Add a new section */
> + section_node = init_config_section(section_name);
> + if (!section_node)
> + return -1;
> + list_add_tail(&section_node->list, sections);
> + }
> +
> + return add_config_element(&section_node->element_head, subkey, value);
> +}
> +
> +static int perf_configset_with_option(configset_fn_t fn, const char *var)
> +{
> + int i, num_dot = 0, num_equals = 0;
> + static char *given_section_name;
> + static char *given_subkey;
> + static char *given_value;
> + const char *last_dot;
> + char *key = strdup(var);
> +
> + if (!key) {
> + pr_err("%s: strdup failed\n", __func__);
> + return -1;
> + }
> + last_dot = strrchr(key, '.');
> + /*
> + * Since "key" actually contains the section name and the real
> + * key name separated by a dot, we have to know where the dot is.
> + */
> + if (last_dot == NULL || last_dot == key) {
> + pr_err("The config variable does not contain a section: %s\n", key);
> + return -1;
> + }
> + if (!last_dot[1]) {
> + pr_err("The config varible does not contain variable name: %s\n", key);
> + return -1;
> + }
> + for (i = 0; key[i]; i++) {
> + if (i == 0 && !isalpha(key[i++]))
> + goto out_err;
> +
> + switch (key[i]) {
> + case '.':
> + num_dot += 1;
> + if (!isalpha(key[++i]))
> + goto out_err;
> + break;
> + case '=':
> + num_equals += 1;
> + break;
> + default:
> + if (!isalpha(key[i]) && !isalnum(key[i]))
> + goto out_err;
> + }
> + }
> +
> + if (num_equals > 1 || num_dot > 1)
> + goto out_err;
> +
> + given_value = strchr(key, '=');
> + if (given_value == NULL || given_value == key)
> + given_value = NULL;
> + else {
> + if (!given_value[1]) {
> + pr_err("The config variable does not contain a value: %s\n", key);
> + return -1;
> + } else
> + given_value++;
> + }
> + given_section_name = strsep(&key, ".");
> + given_subkey = strsep(&key, ".");
> +
> + if (given_value)
> + given_subkey = strsep(&given_subkey, "=");
> +
> + if (!sections) {
> + sections = zalloc(sizeof(*sections));
> + if (!sections)
> + return -1;
> +
> + INIT_LIST_HEAD(sections);
> + perf_config(collect_config, NULL);
> + }
> +
> + return fn(given_section_name, given_subkey, given_value);
> +
> +out_err:
> + pr_err("invalid key: %s", var);
> + return -1;
> +}
> +
> +int cmd_config(int argc, const char **argv, const char *prefix __maybe_unused)
> +{
> + int i, ret = 0;
> + int origin_argc = argc - 1;
> + char *value;
> + bool is_option;
>
> argc = parse_options(argc, argv, config_options, config_usage,
> PARSE_OPT_STOP_AT_NON_OPTION);
> + if (origin_argc > argc)
> + is_option = true;
> + else
> + is_option = false;
> +
> + if (!is_option && argc >= 0) {
> + switch (argc) {
> + case 0:
> + break;
> + default:
> + for (i = 0; argv[i]; i++) {
> + value = strrchr(argv[i], '=');
> + if (value == NULL || value == argv[i])
> + ret = perf_configset_with_option(show_spec_config, argv[i]);
> + else
> + ret = perf_configset_with_option(set_spec_config, argv[i]);
> + if (ret < 0)
> + break;
> + }
> + goto out;
> + }
> + }
>
> if (params.list_action && argc == 0)
> ret = perf_config(show_config, NULL);
> @@ -52,5 +323,6 @@ int cmd_config(int argc, const char **argv, const char *prefix __maybe_unused)
> usage_with_options(config_usage, config_options);
> }
>
> +out:
> return ret;
> }
> diff --git a/tools/perf/util/cache.h b/tools/perf/util/cache.h
> index fbcca21..d333753 100644
> --- a/tools/perf/util/cache.h
> +++ b/tools/perf/util/cache.h
> @@ -1,6 +1,7 @@
> #ifndef __PERF_CACHE_H
> #define __PERF_CACHE_H
>
> +#include <linux/list.h>
> #include <stdbool.h>
> #include "util.h"
> #include "strbuf.h"
> @@ -19,6 +20,22 @@
> #define PERF_DEBUGFS_ENVIRONMENT "PERF_DEBUGFS_DIR"
> #define PERF_TRACEFS_ENVIRONMENT "PERF_TRACEFS_DIR"
>
> +struct config_element {
> + char *subkey;
> + char *value;
> + struct list_head list;
> +};
> +
> +struct config_section {
> + char *name;
> + struct list_head element_head;
> + struct list_head list;
> +};
> +
> +extern struct list_head *sections;
> +
> +typedef int (*configset_fn_t)(const char *, const char *, const char*);
> +extern int perf_configset_write_in_full(void);
> typedef int (*config_fn_t)(const char *, const char *, void *);
> extern int perf_default_config(const char *, const char *, void *);
> extern int perf_config(config_fn_t fn, void *);
> diff --git a/tools/perf/util/config.c b/tools/perf/util/config.c
> index e18f653..71294ef 100644
> --- a/tools/perf/util/config.c
> +++ b/tools/perf/util/config.c
> @@ -21,7 +21,7 @@
> char buildid_dir[MAXPATHLEN]; /* root dir for buildid, binary cache */
>
> static FILE *config_file;
> -static const char *config_file_name;
> +static char *config_file_name;
> static int config_linenr;
> static int config_file_eof;
>
> @@ -420,12 +420,11 @@ static int perf_config_from_file(config_fn_t fn, const char *filename, void *dat
> ret = -1;
> if (f) {
> config_file = f;
> - config_file_name = filename;
> + config_file_name = strdup(filename);
> config_linenr = 1;
> config_file_eof = 0;
> ret = perf_parse_file(fn, data);
> fclose(f);
> - config_file_name = NULL;
> }
> return ret;
> }
> @@ -502,6 +501,31 @@ out:
> return ret;
> }
>
> +int perf_configset_write_in_full(void)
> +{
> + struct config_section *section_node;
> + struct config_element *element_node;
> + const char *first_line = "# this file is auto-generated.";
> + FILE *fp = fopen(config_file_name, "w");
> +
> + if (!fp)
> + return -1;
> +
> + fprintf(fp, "%s\n", first_line);
> + /* overwrite configvariables */
> + list_for_each_entry(section_node, sections, list) {
> + fprintf(fp, "[%s]\n", section_node->name);
> + list_for_each_entry(element_node, &section_node->element_head, list) {
> + if (element_node->value)
> + fprintf(fp, "\t%s = %s\n",
> + element_node->subkey, element_node->value);
> + }
> + }
> + fclose(fp);
> +
> + return 0;
> +}
> +
> /*
> * Call this to report error for your variable that should not
> * get a boolean value (i.e. "[my] var" means "true").
> --
> 1.9.1
>