Re: [PATCH v8 3/5] perf config: Reimplement perf_config() using perf_config_set__it to

[Taeung Song]

Hi, Arnaldo :-D

I also discussed this patchset with Namhyung at offline gathering.
I sent v9 patchset that contains what Namhyung and you advice me to do.
If having your spare time, please review the v9 patchset.
If you do, I'd appreciate it :-)

Thanks,
Taeung

On 06/12/2016 05:57 PM, Taeung Song wrote:
> Hi, Arnaldo
>
> What do you think about setting all actual config variables
> before a sub-command start at perf.c ?
>
> (in order to free the config set that contains all configs
> by perf_config_set__delete() after using it was finished where it was
> needed)
>
> i.e. initialize all actual config variables at perf.c
> instead of at each source file as below.
> (before running a particular sub-command at run_builitin())
>
> util/alias.c
> 22:    perf_config(alias_lookup_cb, NULL);
>
> util/intel-pt.c
> 330:    perf_config(intel_pt_config_div, &d);
> 1993:static int intel_pt_perf_config(const char *var, const char *value,
> void *data)
> 2047:    perf_config(intel_pt_perf_config, pt);
>
> util/data-convert-bt.c
> 1302:    perf_config(convert__config, &c);
>
> util/help-unknown-cmd.c
> 62:    perf_config(perf_unknown_cmd_config, NULL);
>
> builtin-help.c
> 454:    perf_config(perf_help_config, &help_format);
>
> perf.c
> 94:    perf_config(pager_command_config, &c);
> 117:    perf_config(browser_command_config, &c);
> 561:    perf_config(perf_default_config, NULL);
>
> builtin-record.c
> 1432:    perf_config(perf_record_config, rec);
>
> ui/browsers/annotate.c
> 1163:    perf_config(annotate__config, NULL);
>
> ui/browser.c
> 743:    perf_config(ui_browser__color_config, NULL);
>
> builtin-report.c
> 829:    perf_config(report__config, &report);
>
> builtin-kmem.c
> 1899:    perf_config(kmem_config, NULL);
>
> builtin-top.c
> 1231:    perf_config(perf_top_config, &top);
>
>
> If we do, we could set all actual config variables
> before a sub-command work. And the config set that is made
> by perf_config_set__new() would be reused
> when we initialize all actual config variables
> and then if using is is finished, we could free the config set.
>
>
> Thanks,
> Taeung
>
>
> On 06/10/2016 07:58 PM, Taeung Song wrote:
> > On 06/09/2016 10:34 PM, Arnaldo Carvalho de Melo wrote:
> > > Em Wed, Jun 08, 2016 at 09:36:51PM +0900, Taeung Song escreveu:
> > > > Many sub-commands use perf_config() so
> > > > everytime perf_config() is called, perf_config() always read config
> > > > files.
> > > > (i.e. user config '~/.perfconfig' and system config
> > > > '$(sysconfdir)/perfconfig')
> > >
> > > And this is not always a bad thing, think about being in 'mutt' and
> > > adding an entry to ~/.mail_aliases, then going to compose a message,
> > > would be good that the just added entry to ~/.mail_aliases be considered
> > > when adding recipients to your messages, right?
> > >
> > > In the same fashion, 'perf report', 'perf annotate', 'perf top' are long
> > > running utilities that have operations that could get changes to config
> > > files without having to restart them, i.e. do annotation changes in your
> > > ~/.perfconfig and then see them reflected next time you hit 'A´ to
> > > annotate a function in 'perf top' or 'perf report'.
> >
> > Currently, this suggestion isn't already contained among features of
> > perf. right?
> >
> > I understood that you mean while perf process is already running
> > if user change a config file, the changed config can be reflected in
> > 'perf top', 'perf report' or etc without restarting perf process like
> > mutt.
> > Is it right ?
> >
> > > So, I think that if tools want ammortize the cost of reading config
> > > files, they should create an instance of the relevant object
> > > (perf_config_set?) use it and then delete it, but not keep one around
> > > for a long time.
> >
> > I got it.
> >
> > How about the two ideas that I have in mind ?
> >
> > 1) If we eliminate the config set object(perf_config_set) after using it
> > because we don't need to keep it until perf process is done,
> >
> > we could bring many codes using perf_config() at one spot of perf.c ?
> > (because it is hard to decide a point of time we destroy the config set.)
> > For example,
> >
> > (This code isn't executable)
> >
> > diff --git a/tools/perf/perf.c b/tools/perf/perf.c
> > index 15982ce..6a56985 100644
> > --- a/tools/perf/perf.c
> > +++ b/tools/perf/perf.c
> > @@ -77,6 +77,23 @@ struct pager_config {
> >           int val;
> >   };
> >
> > +static void perf_default_config_init(void)
> > +{
> > +        default_colors_config_init();
> > +        default_annoate_config_init();
> > +        default_report_config_init();
> > +        ...
> > +}
> > +
> > +static void perf_config_init(void)
> > +{
> > +        perf_default_config_init();
> > +        colors_config_init();
> > +        annotate_config_init();
> > +        report_config_init();
> > +        ...
> > +}
> > +
> >   static int pager_command_config(const char *var, const char *value,
> > void *data)
> >   {
> >           struct pager_config *c = data;
> > @@ -558,7 +575,7 @@ int main(int argc, const char **argv)
> >
> >           srandom(time(NULL));
> >
> > -        perf_config(perf_default_config, NULL);
> > +        perf_config_init();
> >           set_buildid_dir(NULL);
> >
> >           /* get debugfs/tracefs mount point from /proc/mounts */
> > diff --git a/tools/perf/ui/browser.c b/tools/perf/ui/browser.c
> > index af68a9d..4b827c2 100644
> > --- a/tools/perf/ui/browser.c
> > +++ b/tools/perf/ui/browser.c
> > @@ -740,8 +740,6 @@ void ui_browser__init(void)
> >   {
> >           int i = 0;
> >
> > -        perf_config(ui_browser__color_config, NULL);
> > -
> >           while (ui_browser__colorsets[i].name) {
> >                   struct ui_browser_colorset *c =
> > &ui_browser__colorsets[i++];
> >                   sltt_set_color(c->colorset, c->name, c->fg, c->bg);
> >
> > ... (omitted)
> >
> >
> > Many sub-commands call perf_config() at builtin-report.c, ui/browser.c
> > and etc. So I think it is ambiguous to decide where
> > perf_config_set__delete()
> > will be called instead of at run_builtin().
> >
> > (If the config set's life cycle is the same as perf's ,
> > I would call perf_config_set__delete() at run_builtin()
> > because a sub-command is done)
> >
> >
> > 2) If having the config set for perf's life,
> >
> > we would add configuration features to TUI like TUI configuring options
> > for linux kernel compiling (e.g. make menuconfig) ?
> >
> > Of course, we don't need to have the same function as make menuconfig
> > but IMHO, we could add similar way to menuconfig while perf is running.
> >
> >
> > How do you feel about these ?
> >
> >
> > Thanks, :)
> > Taeung
> >
> > > > But we need to use the config set that already contains all config
> > > > key-value pairs to avoid this repetitive work reading the config files
> > > > in perf_config(). (the config set mean a global variable 'config_set')
> > > >
> > > > In other words, if new perf_config() is called,
> > > > only first time 'config_set' is initialized collecting all configs
> > > > from the config files and it work with perf_config_set__iter().
> > > > And free the config set after a sub-command work at run_builtin().
> > > >
> > > > If we do, 'config_set' can be reused wherever using perf_config()
> > > > and a feature of old perf_config() is the same as new perf_config()
> > > > work
> > > > without the repetitive work that read the 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/builtin-config.c |  4 +++
> > > >   tools/perf/perf.c           |  1 +
> > > >   tools/perf/util/config.c    | 87
> > > > ++++++++++++++++++++++-----------------------
> > > >   tools/perf/util/config.h    |  1 +
> > > >   4 files changed, 48 insertions(+), 45 deletions(-)
> > > >
> > > > diff --git a/tools/perf/builtin-config.c b/tools/perf/builtin-config.c
> > > > index fe1b77f..cfd1036 100644
> > > > --- a/tools/perf/builtin-config.c
> > > > +++ b/tools/perf/builtin-config.c
> > > > @@ -80,6 +80,10 @@ int cmd_config(int argc, const char **argv, const
> > > > char *prefix __maybe_unused)
> > > >       else if (use_user_config)
> > > >           config_exclusive_filename = user_config;
> > > >
> > > > +    /*
> > > > +     * At only 'config' sub-command, individually use the config set
> > > > +     * because of reinitializing with options config file location.
> > > > +     */
> > > >       set = perf_config_set__new();
> > > >       if (!set) {
> > > >           ret = -1;
> > > > diff --git a/tools/perf/perf.c b/tools/perf/perf.c
> > > > index 15982ce..fe2ab7c 100644
> > > > --- a/tools/perf/perf.c> - Arnaldo
> > > > +++ b/tools/perf/perf.c
> > > > @@ -391,6 +391,7 @@ static int run_builtin(struct cmd_struct *p, int
> > > > argc, const char **argv)
> > > >
> > > >       perf_env__set_cmdline(&perf_env, argc, argv);
> > > >       status = p->fn(argc, argv, prefix);
> > > > +    perf_config_set__delete(config_set);
> > > >       exit_browser(status);
> > > >       perf_env__exit(&perf_env);
> > > >       bpf__clear();
> > > > diff --git a/tools/perf/util/config.c b/tools/perf/util/config.c
> > > > index 31e09a4..72db134 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)
> > > >   {
> > > > @@ -478,51 +479,6 @@ 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 = -1;
> > > > -    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)) {
> > > > -        if (perf_config_from_file(fn, perf_etc_perfconfig(), data)
> > > > < 0)
> > > > -            goto out;
> > > > -    }
> > > > -
> > > > -    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);
> > > > -
> > > > -out_free:
> > > > -        free(user_config);
> > > > -    }
> > > > -out:
> > > > -    return ret;
> > > > -}
> > > > -
> > > >   static struct perf_config_section *find_section(struct list_head
> > > > *sections,
> > > >                           const char *section_name)
> > > >   {
> > > > @@ -706,6 +662,47 @@ struct perf_config_set *perf_config_set__new(void)
> > > >       return set;
> > > >   }
> > > >
> > > > +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);
> > > > +                if (fn(key, value, data) < 0) {
> > > > +                    pr_err("Error: wrong config key-value pair
> > > > %s=%s\n",
> > > > +                           key, value);
> > > > +                    return -1;
> > > > +                }
> > > > +            }
> > > > +        }
> > > > +    }
> > > > +
> > > > +    return 0;
> > > > +}
> > > > +
> > > > +int perf_config(config_fn_t fn, void *data)
> > > > +{
> > > > +    if (config_set == NULL)
> > > > +        config_set = perf_config_set__new();
> > > > +
> > > > +    return perf_config_set__iter(config_set, fn, data);
> > > > +}
> > > > +
> > > >   static void perf_config_item__delete(struct perf_config_item *item)
> > > >   {
> > > >       zfree(&item->name);
> > > > diff --git a/tools/perf/util/config.h b/tools/perf/util/config.h
> > > > index 35ccddb..7cc4fea 100644
> > > > --- a/tools/perf/util/config.h
> > > > +++ b/tools/perf/util/config.h
> > > > @@ -21,6 +21,7 @@ struct perf_config_set {
> > > >   };
> > > >
> > > >   extern const char *config_exclusive_filename;
> > > > +extern struct perf_config_set *config_set;
> > > >
> > > >   typedef int (*config_fn_t)(const char *, const char *, void *);
> > > >   int perf_default_config(const char *, const char *, void *);
> > > > --
> > > > 2.5.0