Re: [PATCH] initramfs: restore default compression behaviour

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]


Hi Masahiro,

>From: Masahiro Yamada <masahiroy@xxxxxxxxxx>
>Sent: Wednesday, March 11, 2020 23:12
>To: Eugeniy Paltsev
>Cc: Linux Kernel Mailing List; arcml; Vineet Gupta; Alexey Brodkin
>Subject: Re: [PATCH] initramfs: restore default compression behaviour
>Hi Eugeniy.
>On Wed, Mar 11, 2020 at 7:22 PM Eugeniy Paltsev
><Eugeniy.Paltsev@xxxxxxxxxxxx> wrote:
>> Even though INITRAMFS_SOURCE kconfig option isn't set in most of
>> defconfigs it is used (set) extensively by various build systems.
>> Commit f26661e12765 ("initramfs: make initramfs compression choice
>> non-optional") has changed default compression mode. Previously we
>> compress initramfs using available compression algorithm. Now
>> we don't use any compression at all by default.
>> It significantly increases the image size in case of build system
>> chooses embedded initramfs. Initially I faced with this issue while
>> using buildroot.
>> As of today it's not possible to set preferred compression mode
>> in target defconfig as this option depends on INITRAMFS_SOURCE
>> being set.
>> Modification of build systems doesn't look like good option in this
>> case as it requires to check against kernel version when setting
>> compression mode. The reason for this is that kconfig options
>> describing compression mode was renamed (in same patch series)
>Which commit?
>I do not remember the renaming of kconfig options
>with this regard.

Ok, I've checked it again - looks like I was confused a bit by
as in v5.5 kernel I have in ".config":

And for v5.6-rc1 I have in ".config":

But they are different options actually...

>> so
>> we are not able to simply enable one option for old and new kernels.
>> Given that I propose to use GZIP as default here instead of NO
>> compression. It should be used only when available but given that
>> gzip is enabled by default it looks like good enough choice.
>Another solution would be to move
>INITRAMFS_COMPRESSION_NONE to the end of the choice menu.
>The default of the choice menu is the first visible entry.
>GZIP if RD_GZIP is defined, BZIP2 if RD_BZIP2 is defined ...

Thanks for advice. It looks like an excellent option here, I'll send a patch.

>> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx>
>> ---
>>  usr/Kconfig | 1 +
>>  1 file changed, 1 insertion(+)
>> diff --git a/usr/Kconfig b/usr/Kconfig
>> index bdf5bbd40727..690ef9020819 100644
>> --- a/usr/Kconfig
>> +++ b/usr/Kconfig
>> @@ -102,6 +102,7 @@ config RD_LZ4
>>  choice
>>         prompt "Built-in initramfs compression mode"
>>         depends on INITRAMFS_SOURCE != ""
>>         help
>>           This option allows you to decide by which algorithm the builtin
>> --
>> 2.21.1
>Best Regards
>Masahiro Yamada
linux-snps-arc mailing list

[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]

  Powered by Linux