Nina Schoetterl-Glausch writes:
> From: Pierre Morel
>
> The modification of the CPU attributes are done through a monitor
> command.
>
> It allows to move the core inside the topology tree to optimize
> the cache usage in the case the host's hypervisor previously
> moved the CPU.
>
> The same command allows to modify the CPU attributes modifiers
> like polarization entitlement and the dedicated attribute to notify
> the guest if the host admin modified scheduling or dedication of a vCPU.
>
> With this knowledge the guest has the possibility to optimize the
> usage of the vCPUs.
>
> The command has a feature unstable for the moment.
>
> Signed-off-by: Pierre Morel
> Reviewed-by: Nina Schoetterl-Glausch
> Co-developed-by: Nina Schoetterl-Glausch
> Signed-off-by: Nina Schoetterl-Glausch
> ---
> qapi/machine-target.json | 37 +++
> hw/s390x/cpu-topology.c | 132 +++
> 2 files changed, 169 insertions(+)
>
> diff --git a/qapi/machine-target.json b/qapi/machine-target.json
> index 0d45a590ce..e47a252bd9 100644
> --- a/qapi/machine-target.json
> +++ b/qapi/machine-target.json
> @@ -4,6 +4,8 @@
> # This work is licensed under the terms of the GNU GPL, version 2 or later.
> # See the COPYING file in the top-level directory.
>
> +{ 'include': 'machine-common.json' }
> +
> ##
> # @CpuModelInfo:
> #
> @@ -375,3 +377,38 @@
>'data': [ 'horizontal', 'vertical' ],
> 'if': 'TARGET_S390X'
> }
> +
> +##
> +# @set-cpu-topology:
Move the overview here from [*] below.
> +#
> +# @core-id: the vCPU ID to be moved
> +# @socket-id: optional destination socket where to move the vCPU
> +# @book-id: optional destination book where to move the vCPU
> +# @drawer-id: optional destination drawer where to move the vCPU
> +# @entitlement: optional entitlement
> +# @dedicated: optional, if the vCPU is dedicated to a real CPU
Separate the members with blank lines, please.
The doc generator adds optional automatically, so this will come out
like
"socket-id": "int" (optional)
optional destination socket where to move the vCPU
"book-id": "int" (optional)
optional destination book where to move the vCPU
"drawer-id": "int" (optional)
optional destination drawer where to move the vCPU
"entitlement": "CpuS390Entitlement" (optional)
optional entitlement
"dedicated": "boolean" (optional)
optional, if the vCPU is dedicated to a real CPU
Drop the optional from the text.
Suggest
# @dedicated: whether the vCPU is dedicated to a real CPU
(whatever that may mean; I'm an S390 noob)
> +#
> +# Features:
Another blank line, please.
> +# @unstable: This command may still be modified.
> +#
[*] The overview:
> +# Modifies the topology by moving the CPU inside the topology
> +# tree or by changing a modifier attribute of a CPU.
> +# Default value for optional parameter is the current value
> +# used by the CPU.
So, anything absent will not be changed. Maybe that's a clearer way to
put it. What do you think?
> +#
> +# Returns: Nothing on success, the reason on failure.
> +#
> +# Since: 8.2
> +##
> +{ 'command': 'set-cpu-topology',
> + 'data': {
> + 'core-id': 'uint16',
> + '*socket-id': 'uint16',
> + '*book-id': 'uint16',
> + '*drawer-id': 'uint16',
CpuInstanceProperties uses 'int' for these. Any particular reason for
the difference?
> + '*entitlement': 'CpuS390Entitlement',
> + '*dedicated': 'bool'
> + },
> + 'features': [ 'unstable' ],
> + 'if': { 'all': [ 'TARGET_S390X' , 'CONFIG_KVM' ] }
> +}
[...]