| Message ID | 1424099601-14979-7-git-send-email-p.marczak@samsung.com |
|---|---|
| State | Changes Requested |
| Delegated to: | Minkyu Kang |
| Headers | show |
Hi Przemyslaw, On 16 February 2015 at 08:13, Przemyslaw Marczak <p.marczak@samsung.com> wrote: > Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com> > --- > Kconfig | 26 +++++++++++++++++++------- > 1 file changed, 19 insertions(+), 7 deletions(-) > > diff --git a/Kconfig b/Kconfig > index 4157da3..e08e44a 100644 > --- a/Kconfig > +++ b/Kconfig > @@ -57,13 +57,25 @@ config CC_OPTIMIZE_FOR_SIZE > This option is enabled by default for U-Boot. Ah, you have done this. Then I think you can merge this patch with the dlmalloc patch and drop the README one. > > menuconfig EXPERT > - bool "Configure standard U-Boot features (expert users)" > - help > - This option allows certain base U-Boot options and settings > - to be disabled or tweaked. This is for specialized > - environments which can tolerate a "non-standard" U-Boot. > - Only use this if you really know what you are doing. > - > + bool "Configure standard U-Boot features (expert users)" > + help > + This option allows certain base U-Boot options and settings > + to be disabled or tweaked. This is for specialized > + environments which can tolerate a "non-standard" U-Boot. > + Only use this if you really know what you are doing. > + > +if EXPERT > + config SYS_MALLOC_INIT_SKIP_ZEROING > + bool "Skip memset at malloc init (reduce boot time)" > + help > + This avoids zeroing memory reserved for malloc at malloc init. > + Significant boot time reduction is visible for configs in which > + CONFIG_SYS_MALLOC_LEN value, has more than few MiB. > + Useful for bzip2, bmp logo. > + Warning: > + When enable, make sure that calloc() is used when zeroed > + memory is needed. > +endif > endmenu # General setup > > menu "Boot images" > -- > 1.9.1 > Regards, Simon
Hi Simon, On 02/18/2015 05:32 AM, Simon Glass wrote: > Hi Przemyslaw, > > On 16 February 2015 at 08:13, Przemyslaw Marczak <p.marczak@samsung.com> wrote: >> Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com> >> --- >> Kconfig | 26 +++++++++++++++++++------- >> 1 file changed, 19 insertions(+), 7 deletions(-) >> >> diff --git a/Kconfig b/Kconfig >> index 4157da3..e08e44a 100644 >> --- a/Kconfig >> +++ b/Kconfig >> @@ -57,13 +57,25 @@ config CC_OPTIMIZE_FOR_SIZE >> This option is enabled by default for U-Boot. > > Ah, you have done this. Then I think you can merge this patch with the > dlmalloc patch and drop the README one. > Shouldn't we keep both, README and Kconfig help? Kconfig is just a configuration tool, README is a documentation. Sometimes it could be faster to find something in the text instead of config. >> >> menuconfig EXPERT >> - bool "Configure standard U-Boot features (expert users)" >> - help >> - This option allows certain base U-Boot options and settings >> - to be disabled or tweaked. This is for specialized >> - environments which can tolerate a "non-standard" U-Boot. >> - Only use this if you really know what you are doing. >> - >> + bool "Configure standard U-Boot features (expert users)" >> + help >> + This option allows certain base U-Boot options and settings >> + to be disabled or tweaked. This is for specialized >> + environments which can tolerate a "non-standard" U-Boot. >> + Only use this if you really know what you are doing. >> + >> +if EXPERT >> + config SYS_MALLOC_INIT_SKIP_ZEROING >> + bool "Skip memset at malloc init (reduce boot time)" >> + help >> + This avoids zeroing memory reserved for malloc at malloc init. >> + Significant boot time reduction is visible for configs in which >> + CONFIG_SYS_MALLOC_LEN value, has more than few MiB. >> + Useful for bzip2, bmp logo. >> + Warning: >> + When enable, make sure that calloc() is used when zeroed >> + memory is needed. >> +endif >> endmenu # General setup >> >> menu "Boot images" >> -- >> 1.9.1 >> > > Regards, > Simon > Best regards,
+Masahiro Hi, On 18 February 2015 at 05:40, Przemyslaw Marczak <p.marczak@samsung.com> wrote: > Hi Simon, > > On 02/18/2015 05:32 AM, Simon Glass wrote: >> >> Hi Przemyslaw, >> >> On 16 February 2015 at 08:13, Przemyslaw Marczak <p.marczak@samsung.com> >> wrote: >>> >>> Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com> >>> --- >>> Kconfig | 26 +++++++++++++++++++------- >>> 1 file changed, 19 insertions(+), 7 deletions(-) >>> >>> diff --git a/Kconfig b/Kconfig >>> index 4157da3..e08e44a 100644 >>> --- a/Kconfig >>> +++ b/Kconfig >>> @@ -57,13 +57,25 @@ config CC_OPTIMIZE_FOR_SIZE >>> This option is enabled by default for U-Boot. >> >> >> Ah, you have done this. Then I think you can merge this patch with the >> dlmalloc patch and drop the README one. >> > > Shouldn't we keep both, README and Kconfig help? > Kconfig is just a configuration tool, README is a documentation. > Sometimes it could be faster to find something in the text instead of > config. Agreed, but isn't it going to be a pain to add it in both places and keep it in sync? Maybe we could create a script which creates a README.kconfig containing all the options and help. > > >>> >>> menuconfig EXPERT >>> - bool "Configure standard U-Boot features (expert users)" >>> - help >>> - This option allows certain base U-Boot options and settings >>> - to be disabled or tweaked. This is for specialized >>> - environments which can tolerate a "non-standard" U-Boot. >>> - Only use this if you really know what you are doing. >>> - >>> + bool "Configure standard U-Boot features (expert users)" >>> + help >>> + This option allows certain base U-Boot options and settings >>> + to be disabled or tweaked. This is for specialized >>> + environments which can tolerate a "non-standard" U-Boot. >>> + Only use this if you really know what you are doing. >>> + >>> +if EXPERT >>> + config SYS_MALLOC_INIT_SKIP_ZEROING >>> + bool "Skip memset at malloc init (reduce boot time)" >>> + help >>> + This avoids zeroing memory reserved for malloc at malloc init. >>> + Significant boot time reduction is visible for configs in which >>> + CONFIG_SYS_MALLOC_LEN value, has more than few MiB. >>> + Useful for bzip2, bmp logo. >>> + Warning: >>> + When enable, make sure that calloc() is used when zeroed >>> + memory is needed. >>> +endif >>> endmenu # General setup >>> >>> menu "Boot images" Regards, Simon
On Thu, 19 Feb 2015 11:59:07 -0700 Simon Glass <sjg@chromium.org> wrote: > +Masahiro > > Hi, > > On 18 February 2015 at 05:40, Przemyslaw Marczak <p.marczak@samsung.com> wrote: > > Hi Simon, > > > > On 02/18/2015 05:32 AM, Simon Glass wrote: > >> > >> Hi Przemyslaw, > >> > >> On 16 February 2015 at 08:13, Przemyslaw Marczak <p.marczak@samsung.com> > >> wrote: > >>> > >>> Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com> > >>> --- > >>> Kconfig | 26 +++++++++++++++++++------- > >>> 1 file changed, 19 insertions(+), 7 deletions(-) > >>> > >>> diff --git a/Kconfig b/Kconfig > >>> index 4157da3..e08e44a 100644 > >>> --- a/Kconfig > >>> +++ b/Kconfig > >>> @@ -57,13 +57,25 @@ config CC_OPTIMIZE_FOR_SIZE > >>> This option is enabled by default for U-Boot. > >> > >> > >> Ah, you have done this. Then I think you can merge this patch with the > >> dlmalloc patch and drop the README one. > >> > > > > Shouldn't we keep both, README and Kconfig help? > > Kconfig is just a configuration tool, README is a documentation. > > Sometimes it could be faster to find something in the text instead of > > config. > > Agreed, but isn't it going to be a pain to add it in both places and > keep it in sync? Maybe we could create a script which creates a > README.kconfig containing all the options and help. > I agree with Simon. README is useful when we need a wider and more general explanation about a feature, for ex. doc/driver-model/README.txt Per-config explanation should be documented in Kconfig only. Another reasone I prefer Kconfig help is: When we remove a CONFIG from Kconfig, the documentation in a separete README might be left over. BTW, I did not know that U-Boot filled all the malloc space with zero. I guess our consensus is that malloc() returns uninitialized memory. So, I am happy with this patch. (Perhaps, could it be enabled by default? ) Best Regards Masahiro Yamada
Hello, On 02/20/2015 08:32 AM, Masahiro Yamada wrote: > > On Thu, 19 Feb 2015 11:59:07 -0700 > Simon Glass <sjg@chromium.org> wrote: > >> +Masahiro >> >> Hi, >> >> On 18 February 2015 at 05:40, Przemyslaw Marczak <p.marczak@samsung.com> wrote: >>> Hi Simon, >>> >>> On 02/18/2015 05:32 AM, Simon Glass wrote: >>>> >>>> Hi Przemyslaw, >>>> >>>> On 16 February 2015 at 08:13, Przemyslaw Marczak <p.marczak@samsung.com> >>>> wrote: >>>>> >>>>> Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com> >>>>> --- >>>>> Kconfig | 26 +++++++++++++++++++------- >>>>> 1 file changed, 19 insertions(+), 7 deletions(-) >>>>> >>>>> diff --git a/Kconfig b/Kconfig >>>>> index 4157da3..e08e44a 100644 >>>>> --- a/Kconfig >>>>> +++ b/Kconfig >>>>> @@ -57,13 +57,25 @@ config CC_OPTIMIZE_FOR_SIZE >>>>> This option is enabled by default for U-Boot. >>>> >>>> >>>> Ah, you have done this. Then I think you can merge this patch with the >>>> dlmalloc patch and drop the README one. >>>> >>> >>> Shouldn't we keep both, README and Kconfig help? >>> Kconfig is just a configuration tool, README is a documentation. >>> Sometimes it could be faster to find something in the text instead of >>> config. >> >> Agreed, but isn't it going to be a pain to add it in both places and >> keep it in sync? Maybe we could create a script which creates a >> README.kconfig containing all the options and help. >> > > I agree with Simon. > > README is useful when we need a wider and more general explanation about a feature, > for ex. doc/driver-model/README.txt > > Per-config explanation should be documented in Kconfig only. > > Another reasone I prefer Kconfig help is: > When we remove a CONFIG from Kconfig, the documentation in a separete README > might be left over. > Yes, but this is the maintainer role, to keep it in sync. It's no problem for me. I can remove the README entry. I just think that it may be useful for people who just starting the fun with U-Boot. > > BTW, I did not know that U-Boot filled all the malloc space with zero. The same as I, but checking the execution time of some functions, shows that something takes too long time. > > I guess our consensus is that malloc() returns uninitialized memory. Yes, as should it do. > > So, I am happy with this patch. (Perhaps, could it be enabled by default? ) > This could potentially break something. Let's give a free hand to maintainers to enable this after test. And this is why I add such config option. > > > Best Regards > Masahiro Yamada > > So as Simon and Masahiro wish, I will remove the README entry for this. Best regards,
diff --git a/Kconfig b/Kconfig index 4157da3..e08e44a 100644 --- a/Kconfig +++ b/Kconfig @@ -57,13 +57,25 @@ config CC_OPTIMIZE_FOR_SIZE This option is enabled by default for U-Boot. menuconfig EXPERT - bool "Configure standard U-Boot features (expert users)" - help - This option allows certain base U-Boot options and settings - to be disabled or tweaked. This is for specialized - environments which can tolerate a "non-standard" U-Boot. - Only use this if you really know what you are doing. - + bool "Configure standard U-Boot features (expert users)" + help + This option allows certain base U-Boot options and settings + to be disabled or tweaked. This is for specialized + environments which can tolerate a "non-standard" U-Boot. + Only use this if you really know what you are doing. + +if EXPERT + config SYS_MALLOC_INIT_SKIP_ZEROING + bool "Skip memset at malloc init (reduce boot time)" + help + This avoids zeroing memory reserved for malloc at malloc init. + Significant boot time reduction is visible for configs in which + CONFIG_SYS_MALLOC_LEN value, has more than few MiB. + Useful for bzip2, bmp logo. + Warning: + When enable, make sure that calloc() is used when zeroed + memory is needed. +endif endmenu # General setup menu "Boot images"
Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com> --- Kconfig | 26 +++++++++++++++++++------- 1 file changed, 19 insertions(+), 7 deletions(-)