Re: [PATCH v23 01/20] CPU topology: extend with s390 specifics

[Markus Armbruster]

Nina Schoetterl-Glausch <nsg@linux.ibm.com> writes:

> On Tue, 2023-09-19 at 14:47 +0200, Markus Armbruster wrote:
>> Nina Schoetterl-Glausch <nsg@linux.ibm.com> writes:
>> 
>> > From: Pierre Morel <pmorel@linux.ibm.com>
>> > 
>> > S390 adds two new SMP levels, drawers and books to the CPU
>> > topology.
>> > S390 CPUs have specific topology features like dedication and
>> > entitlement. These indicate to the guest information on host
>> > vCPU scheduling and help the guest make better scheduling decisions.
>> > 
>> > Let us provide the SMP properties with books and drawers levels
>> > and S390 CPU with dedication and entitlement,
>> > 
>> > Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
>> > Reviewed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
>> > Co-developed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
>> > Signed-off-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
>> > ---
>> >  qapi/machine-common.json            | 21 +++++++++++++
>> >  qapi/machine.json                   | 19 ++++++++++--
>> >  include/hw/boards.h                 | 10 +++++-
>> >  include/hw/qdev-properties-system.h |  4 +++
>> >  target/s390x/cpu.h                  |  6 ++++
>> >  hw/core/machine-smp.c               | 48 ++++++++++++++++++++++++-----
>> >  hw/core/machine.c                   |  4 +++
>> >  hw/core/qdev-properties-system.c    | 13 ++++++++
>> >  hw/s390x/s390-virtio-ccw.c          |  4 +++
>> >  softmmu/vl.c                        |  6 ++++
>> >  target/s390x/cpu.c                  |  7 +++++
>> >  qapi/meson.build                    |  1 +
>> >  qemu-options.hx                     |  7 +++--
>> >  13 files changed, 137 insertions(+), 13 deletions(-)
>> >  create mode 100644 qapi/machine-common.json
>> > 
>> > diff --git a/qapi/machine-common.json b/qapi/machine-common.json
>> > new file mode 100644
>> > index 0000000000..e40421bb37
>> > --- /dev/null
>> > +++ b/qapi/machine-common.json
>> 
>> Why do you need a separate QAPI sub-module?
>> 
>> > @@ -0,0 +1,21 @@
>> > +# -*- Mode: Python -*-
>> > +# vim: filetype=python
>> > +#
>> > +# This work is licensed under the terms of the GNU GPL, version 2 or 
>> > later.
>> > +# See the COPYING file in the top-level directory.
>> > +
>> > +##
>> > +# = Machines S390 data types
>> > +##
>> > +
>> > +##
>> > +# @CpuS390Entitlement:
>> > +#
>> > +# An enumeration of cpu entitlements that can be assumed by a virtual
>> > +# S390 CPU
>> > +#
>> > +# Since: 8.2
>> > +##
>> > +{ 'enum': 'CpuS390Entitlement',
>> > +  'prefix': 'S390_CPU_ENTITLEMENT',
>> > +  'data': [ 'auto', 'low', 'medium', 'high' ] }
>> > diff --git a/qapi/machine.json b/qapi/machine.json
>> > index a08b6576ca..a63cb951d2 100644
>> > --- a/qapi/machine.json
>> > +++ b/qapi/machine.json
>> > @@ -9,6 +9,7 @@
>>    ##
>>    # = Machines
>> >  ##
>> >  
>> >  { 'include': 'common.json' }
>> > +{ 'include': 'machine-common.json' }
>> 
>> Section structure is borked :)
>> 
>> Existing section "Machine" now ends at the new "Machines S390 data
>> types" you pull in here.  The contents of below moves from "Machines" to
>> "Machines S390 data types".
>> 
>> Before I explain how to avoid this, I'd like to understand why we need a
>> new sub-module.
>
> Should I just move the include statements above the section header?
> I assume I could also include it in qapi-schema.json before the machine.json
> include and that that is the reason we don't have
> the same problem with e.g. migration.json.
> But just moving the includes seems cleaner.

qapi-schema.json should include all sub-modules in the order desired for
the manual.

Do double-check the generated manual's section structure when adding
sections or moving include directives.