Re: [Qemu-devel] [PATCH V1 RESEND 4/6] numa: Extend the command-line to provide memory latency and bandwidth information

[Eric Blake]

On 06/19/2018 10:20 AM, Liu Jingqi wrote:
> Add -numa hmat-lb option to provide System Locality Latency and
> Bandwidth Information. These memory attributes help to build
> System Locality Latency and Bandwidth Information Structure(s)
> in ACPI Heterogeneous Memory Attribute Table (HMAT).
>
> Signed-off-by: Liu Jingqi <address@hidden>
> ---
>   numa.c          | 124 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>   qapi/misc.json  |  92 ++++++++++++++++++++++++++++++++++++++++-
>   qemu-options.hx |  28 ++++++++++++-
>   3 files changed, 241 insertions(+), 3 deletions(-)

> +++ b/qapi/misc.json
> @@ -2736,10 +2736,12 @@
>   #
>   # @cpu: property based CPU(s) to node mapping (Since: 2.10)
>   #
> +# @hmat-lb: memory latency and bandwidth information (Since: 2.13)

s/2.13/3.0/ through your series


>   ##
> +# @HmatLBMemoryHierarchy:
> +#
> +# The memory hierarchy in the System Locality Latency
> +# and Bandwidth Information Structure of HMAT

Worth including the expansion of the acronym HMAT for someone not 
familiar with the term?

> +#
> +# @memory: the structure represents the memory performance
> +#
> +# @last-level: last level memory of memory side cached memory
> +#
> +# @1st-level: first level memory of memory side cached memory
> +#
> +# @2nd-level: second level memory of memory side cached memory
> +#
> +# @3rd-level: third level memory of memory side cached memory
> +#
> +# Since: 2.13
> +##
> +{ 'enum': 'HmatLBMemoryHierarchy',
> +  'data': [ 'memory', 'last-level', '1st-level',
> +            '2nd-level', '3rd-level' ] }

enum values starting with a digit is permitted for legacy reasons, but 
I'm reluctant to add more without good cause.  Can you spell these 
'first, second, third' instead of '1st, 2nd, 3rd'?

> +
> +##
> +# @HmatLBDataType:
> +#
> +# Data type in the System Locality Latency
> +# and Bandwidth Information Structure of HMAT
> +#
> +# @access-latency: access latency
> +#
> +# @read-latency: read latency
> +#
> +# @write-latency: write latency
> +#
> +# @access-bandwidth: access bandwitch

s/witch/width/

Also, in what units are these numbers?

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org