Re: [PATCH v2 00/12] user-mode: Prune build dependencies (part 1)

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 3/16/20 1:16 AM, Aleksandar Markovic wrote:
> 
> 
> On Monday, March 16, 2020, Philippe Mathieu-Daudé <philmd@redhat.com 
> <mailto:philmd@redhat.com>> wrote:
> 
>     This is the first part of a series reducing user-mode
>     dependencies. By stripping out unused code, the build
>     and testing time is reduced (as is space used by objects).
> 
>     Part 1:
>     - reduce user-mode object list
>     - remove some migration code from user-mode
>     - remove cpu_get_crash_info()
> 
> 
> What is the purpose of dividing into parts? What is the content of other 
> parts, and when do you plan to submit those? A series is usually a 
> stand-alone and a complete logical unit - why did you decide to submit 
> "parts" separately (just curious)?

Big series are hard to digest and scare reviewers. Peter told me twice 
his rule of thumb is to split a series if it gets bigger than 20 patches 
(and a patch if it modify more than 200 lines). He also recently said he 
skipped review of a ~32 patches series of mine which was too big. I 
don't want other reviewers to do that neither, so I try to split <=20.

Each series could be applied apart, except the last patch from the 3rd 
part (qapi: Restrict code generated for user-mode) which is the one 
really cutting down user-mode code by avoiding pulling in system-mode 
symbols.

First part is generic, second part is QAPI-related, and third part 
concerns hw/core/qdev-properties.c. Each part is covered by different 
maintainers.

> 
> Does this series affect executables' size, or cut build times only?

Both. It will saves us CI testing time, save time to distributions 
packaging linux-user-only builds, produce smaller binaries.

> 
> Thanks,
> Aleksandar
> 
>     Since v1:
>     - Addressed Laurent/Richard review comments
>     - Removed 'exec: Drop redundant #ifdeffery'
>     - Removed 'target: Restrict write_elfXX_note() handlers to system-mode'
> 
>     v1:
>     https://www.mail-archive.com/qemu-devel@nongnu.org/msg688456.html
>     <https://www.mail-archive.com/qemu-devel@nongnu.org/msg688456.html>
> 
>     Philippe Mathieu-Daudé (12):
>        Makefile: Only build virtiofsd if system-mode is enabled
>        configure: Avoid building TCG when not needed
>        tests/Makefile: Only display TCG-related tests when TCG is available
>        tests/Makefile: Restrict some softmmu-only tests
>        util/Makefile: Reduce the user-mode object list
>        stubs/Makefile: Reduce the user-mode object list
>        target/riscv/cpu: Restrict CPU migration to system-mode
>        exec: Assert CPU migration is not used on user-only build
>        arch_init: Remove unused 'qapi-commands-misc.h' include
>        target/i386: Restrict CpuClass::get_crash_info() to system-mode
>        target/s390x: Restrict CpuClass::get_crash_info() to system-mode
>        hw/core: Restrict CpuClass::get_crash_info() to system-mode
> 
>       configure              |  4 +++
>       Makefile               |  2 +-
>       include/hw/core/cpu.h  |  7 ++++-
>       arch_init.c            |  1 -
>       exec.c                 |  4 ++-
>       hw/core/cpu.c          |  2 ++
>       target/i386/cpu.c      |  6 ++++-
>       target/riscv/cpu.c     |  6 +++--
>       target/s390x/cpu.c     | 12 ++++-----
>       stubs/Makefile.objs    | 52 +++++++++++++++++++++----------------
>       tests/Makefile.include | 18 +++++++------
>       util/Makefile.objs     | 59 +++++++++++++++++++++++++++---------------
>       12 files changed, 108 insertions(+), 65 deletions(-)
> 
>     -- 
>     2.21.1
> 
>