Re: [PATCH v2 0/2] ISAR SDK image support

[Henning Schild <henning.schild@siemens.com>]

Am Fri, 18 May 2018 13:01:08 +0200
schrieb "Maxim Yu. Osipov" <mosipov@ilbers.de>:

> Hello Henning,
> 
> Thank you very much for your feedback.
> I'm new in the project and your suggestions
> are very welcome.
> 
> Let me first describe my understanding of the ISAR SDK image
> use case scenario:
> 
> We have a team of developers who need to develop application in ISAR 
> ecosystem. Somebody (let's call him project's leader) has Debian
> based PC workstation with installed ISAR ecosystem and he has to
> quickly pass ISAR build environment to other developers, which
> probably have other Linux distributions like Fedora/Suse etc.

So far so good, but they might have Windows or MacOS as well.

> The provided patch solves this problem - team leader just builds 
> required isar-image-sdk and passes the resulting ISAR image or ISAR 
> rootfs tarball to developers - they just chroot to this image and may 
> start developing application.

chroot is not available on the OS the developers are used/forced to work
in

> This works fine for x86, but as you absolutely right
> 
>  > While it will work for arm(64) on x86 you will end up with a
>  > horribly slow SDK. Horribly slow is OK for building the image with
>  > Isar, not for the fast turn-around you are looking for as a
>  > developer.  
> 
> The proposed solution is just to flash ISAR image on the ARM target
> (as modern ARM targets are quite powerful) and develop the
> application natively on the target (like this is done in raspbian
> world).

And this is exactly the point where i think you are wrong. Developers
do not want to or can not deal with additional hardware. It is
cumbersome and HW might not be available. We need something that works
on one machine (the developers notebook).
So the --sysroot for devs with any Linux + cross toolchain, and for the
Windows guys a whole Linux + cross toolchain to wrap it all into a
VM-image.

> I hope this clarifies the idea behind the patch,

The idea was clear but that way has the mentioned limitations.

Henning

> Kind regards,
> Maxim.
> 
> On 05/18/2018 10:33 AM, Henning Schild wrote:
> > Am Wed, 16 May 2018 17:56:51 +0200
> > schrieb "Maxim Yu. Osipov" <mosipov@ilbers.de>:
> >   
> >> Hello everybody,
> >>
> >> Please ignore previous patch series.
> >>
> >> This series introduces ISAR SDK image support.  
> > 
> > Thanks for looking into that!
> > 
> > As i explained here
> > https://groups.google.com/forum/#!topic/isar-users/bxmZQD8sSDQ  
> 
> > There are two general ways to prepare an SDK. The image+devtools and
> > the "--sysroot" of buildchroot way. You have implemented
> > image+devtools which is only practical for non qemu-user-static
> > setups ... basically just for x86 targets.
> > 
> > While it will work for arm(64) on x86 you will end up with a
> > horribly slow SDK. Horribly slow is OK for building the image with
> > Isar, not for the fast turn-around you are looking for as a
> > developer.
> > 
> > What should be done instead is extracting the buildchroot and using
> > it from the outside with "--sysroot", add example for make, CMake,
> > eclipse And maybe creating an x86 Debian rootfs with the cross
> > compiler that contains all that.
> > 
> > Henning
> >   
> >> In order to create ISAR SDK image just add package isar-sdk into
> >> variable IMAGE_INSTALL in bitbake's conf/local.conf and fireup the
> >> ISAR image build.
> >>
> >> When build is done, perform the following steps:
> >>
> >> 1) Copy host's hostname and resolv.conf into resulting rootfs:
> >>
> >> For example,
> >>
> >> sudo cp /etc/hostname
> >> $HOME/isar/src/build/tmp/work/debian-stretch-amd64/isar-image-base/rootfs/etc
> >> sudo cp /etc/resolv.conf
> >> $HOME/isar/src/build/tmp/work/debian-stretch-amd64/isar-image-base/rootfs/etc
> >>
> >> 2) Mount the following directories in chroot by passing resulting
> >> rootfs as an argument to the script mount_chroot.sh:
> >>
> >> $ cat mount_chroot.sh
> >> #!/bin/bash
> >> sudo mount /tmp     $1/tmp                 -o bind
> >> sudo mount proc     $1/proc    -t proc     -o nosuid,noexec,nodev
> >> sudo mount sysfs    $1/sys     -t sysfs    -o nosuid,noexec,nodev
> >> sudo mount devtmpfs $1/dev     -t devtmpfs -o mode=0755,nosuid
> >> sudo mount devpts   $1/dev/pts -t devpts   -o gid=5,mode=620
> >> sudo mount tmpfs    $1/dev/shm -t tmpfs    -o
> >> rw,seclabel,nosuid,nodev
> >>
> >> $./mount_chroot.sh
> >> $HOME/isar/src/build/tmp/work/debian-stretch-amd64/isar-image-base/rootfs  
> > 
> > Should that helper not be part of the patch series?
> >   
> >> 3) chroot to isar SDK rootfs:
> >>
> >> $sudo chroot
> >> $HOME/isar/src/build/tmp/work/debian-stretch-amd64/isar-image-base/rootfs
> >>
> >> 4) In chroot change user to 'builder', cd to directory isar and
> >> start the isar image generation as usual.
> >>
> >> For example,
> >>
> >> root@tiberius:/# su - builder
> >> builder@tiberius:~$ cd isar/
> >> builder@tiberius:~/isar$ . isar-init-build-env ../build/
> >> builder@tiberius:~/build$ bitbake
> >> multiconfig:qemuamd64-stretch:isar-image-base
> >>
> >>
> >> Kind regards,
> >> Maxim.
> >>
> >> Alexander Smirnov (1):
> >>    isar-bitbake: Add AUTOREV definition
> >>
> >> Maxim Yu. Osipov (1):
> >>    image: Add ISAR SDK package to create SDK from any rootfs image.
> >>
> >>   meta-isar/recipes-core/images/isar-image-sdk.bb |  9 ++++++
> >>   meta/conf/isar-bitbake.conf                     |  2 ++
> >>   meta/recipes-devtools/isar-sdk/files/README     |  2 ++
> >>   meta/recipes-devtools/isar-sdk/files/postinst   | 21
> >> +++++++++++++ meta/recipes-devtools/isar-sdk/isar-sdk.bb      | 42
> >> +++++++++++++++++++++++++ 5 files changed, 76 insertions(+)
> >>   create mode 100644
> >> meta-isar/recipes-core/images/isar-image-sdk.bb create mode 100644
> >> meta/recipes-devtools/isar-sdk/files/README create mode 100644
> >> meta/recipes-devtools/isar-sdk/files/postinst create mode 100644
> >> meta/recipes-devtools/isar-sdk/isar-sdk.bb 
> >   
> 
>