Hi Ulf,
2018-01-12 23:28 GMT+09:00 Ulf Magnusson <ulfalizer@xxxxxxxxx>:
> On Wed, Jan 10, 2018 at 7:56 AM, Masahiro Yamada
> <yamada.masahiro@xxxxxxxxxxxxx> wrote:
>> (all)defconfig does not need to call conf_set_all_new_symbols() because
>> conf_write() calculates all symbols based on their default unless they
>> have been user-defined.
>>
>> conf_set_all_new_symbols(def_default) is no-op except for "choice".
>> It calls sym_cal_value() for "choice", but the SYMBOL_VALID is cleared
>> by set_all_choice_values() later on. So, conf_write() will re-calculate
>> it, which is just a wasteful computation. The only difference I see
>> is SYMBOL_DEF_USER flag for "choice", but it gives no difference to the
>> resulted .config file.
>>
>> I confirmed this change still produced the same .config for all ARCH.
>>
>> I also moved savedefconfig to collect the no-op cases at the end of
>> the switch statement.
>>
>> Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
>> ---
>>
>> scripts/kconfig/conf.c | 11 +++--------
>> 1 file changed, 3 insertions(+), 8 deletions(-)
>>
>> diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c
>> index 52cbe5d..8364811 100644
>> --- a/scripts/kconfig/conf.c
>> +++ b/scripts/kconfig/conf.c
>> @@ -655,18 +655,10 @@ int main(int ac, char **av)
>> case allmodconfig:
>> conf_set_all_new_symbols(def_mod);
>> break;
>> - case alldefconfig:
>> - conf_set_all_new_symbols(def_default);
>> - break;
>> case randconfig:
>> /* Really nothing to do in this loop */
>> while (conf_set_all_new_symbols(def_random)) ;
>> break;
>> - case defconfig:
>> - conf_set_all_new_symbols(def_default);
>> - break;
>> - case savedefconfig:
>> - break;
>> case oldaskconfig:
>> rootEntry = &rootmenu;
>> conf(&rootmenu);
>> @@ -681,7 +673,10 @@ int main(int ac, char **av)
>> check_conf(&rootmenu);
>> } while (conf_cnt && input_mode != listnewconfig);
>> break;
>> + case alldefconfig:
>> + case defconfig:
>> case olddefconfig:
>> + case savedefconfig:
>> default:
>> break;
>> }
>> --
>> 2.7.4
>>
>
> Another side effect of conf_set_all_new_symbols(def_default) is that
> SYMBOL_NEED_SET_CHOICE_VALUES is set on all choice values. Might want
> to check fbe98bb9ed3d ("kconfig: Fix defconfig when one choice menu
> selects options that another choice menu depends on") to make sure
> nothing breaks related to that.
>
> Cheers,
> Ulf
> --
Thanks for your comments!
>From a quick test, this patch seems OK,
but I need to take a closer look at this.
--
Best Regards
Masahiro Yamada
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