Re: [PATCH v9 18/21] hw/i386/pc: Support smp.modules for x86 PC machine

["Moger, Babu" <babu.moger@amd.com>]

Hi Zhao,

On 2/27/24 04:32, Zhao Liu wrote:
> From: Zhao Liu <zhao1.liu@intel.com>
> 
> As module-level topology support is added to X86CPU, now we can enable
> the support for the modules parameter on PC machines. With this support,
> we can define a 5-level x86 CPU topology with "-smp":
> 
> -smp cpus=*,maxcpus=*,sockets=*,dies=*,modules=*,cores=*,threads=*.
> 
> Additionally, add the 5-level topology example in description of "-smp".
> 
> Tested-by: Yongwei Ma <yongwei.ma@intel.com>
> Co-developed-by: Zhuocheng Ding <zhuocheng.ding@intel.com>
> Signed-off-by: Zhuocheng Ding <zhuocheng.ding@intel.com>
> Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
> ---
> Changes since v8:
>  * Add missing "modules" parameter in -smp example.
> 
> Changes since v7:
>  * Supported modules instead of clusters for PC.
>  * Dropped Michael/Babu/Yanan's ACKed/Tested/Reviewed tags since the
>    code change.
>  * Re-added Yongwei's Tested tag For his re-testing.
> ---
>  hw/i386/pc.c    |  1 +
>  qemu-options.hx | 18 ++++++++++--------
>  2 files changed, 11 insertions(+), 8 deletions(-)
> 
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index f8eb684a4926..b270a66605fc 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -1830,6 +1830,7 @@ static void pc_machine_class_init(ObjectClass *oc, void *data)
>      mc->default_cpu_type = TARGET_DEFAULT_CPU_TYPE;
>      mc->nvdimm_supported = true;
>      mc->smp_props.dies_supported = true;
> +    mc->smp_props.modules_supported = true;
>      mc->default_ram_id = "pc.ram";
>      pcmc->default_smbios_ep_type = SMBIOS_ENTRY_POINT_TYPE_64;
>  
> diff --git a/qemu-options.hx b/qemu-options.hx
> index 9be1e5817c7d..b5784fda32cb 100644
> --- a/qemu-options.hx
> +++ b/qemu-options.hx
> @@ -281,7 +281,8 @@ ERST
>  
>  DEF("smp", HAS_ARG, QEMU_OPTION_smp,
>      "-smp [[cpus=]n][,maxcpus=maxcpus][,drawers=drawers][,books=books][,sockets=sockets]\n"
> -    "               [,dies=dies][,clusters=clusters][,cores=cores][,threads=threads]\n"
> +    "               [,dies=dies][,clusters=clusters][,modules=modules][,cores=cores]\n"
> +    "               [,threads=threads]\n"
>      "                set the number of initial CPUs to 'n' [default=1]\n"
>      "                maxcpus= maximum number of total CPUs, including\n"
>      "                offline CPUs for hotplug, etc\n"
> @@ -290,7 +291,8 @@ DEF("smp", HAS_ARG, QEMU_OPTION_smp,
>      "                sockets= number of sockets in one book\n"
>      "                dies= number of dies in one socket\n"
>      "                clusters= number of clusters in one die\n"
> -    "                cores= number of cores in one cluster\n"
> +    "                modules= number of modules in one cluster\n"
> +    "                cores= number of cores in one module\n"
>      "                threads= number of threads in one core\n"
>      "Note: Different machines may have different subsets of the CPU topology\n"
>      "      parameters supported, so the actual meaning of the supported parameters\n"
> @@ -306,7 +308,7 @@ DEF("smp", HAS_ARG, QEMU_OPTION_smp,
>      "      must be set as 1 in the purpose of correct parsing.\n",
>      QEMU_ARCH_ALL)
>  SRST
> -``-smp [[cpus=]n][,maxcpus=maxcpus][,sockets=sockets][,dies=dies][,clusters=clusters][,cores=cores][,threads=threads]``
> +``-smp [[cpus=]n][,maxcpus=maxcpus][,drawers=drawers][,books=books][,sockets=sockets][,dies=dies][,clusters=clusters][,modules=modules][,cores=cores][,threads=threads]``

You have added drawers, books here. Were they missing before?

>      Simulate a SMP system with '\ ``n``\ ' CPUs initially present on
>      the machine type board. On boards supporting CPU hotplug, the optional
>      '\ ``maxcpus``\ ' parameter can be set to enable further CPUs to be
> @@ -345,14 +347,14 @@ SRST
>          -smp 8,sockets=2,cores=2,threads=2,maxcpus=8
>  
>      The following sub-option defines a CPU topology hierarchy (2 sockets
> -    totally on the machine, 2 dies per socket, 2 cores per die, 2 threads
> -    per core) for PC machines which support sockets/dies/cores/threads.
> -    Some members of the option can be omitted but their values will be
> -    automatically computed:
> +    totally on the machine, 2 dies per socket, 2 modules per die, 2 cores per
> +    module, 2 threads per core) for PC machines which support sockets/dies
> +    /modules/cores/threads. Some members of the option can be omitted but
> +    their values will be automatically computed:
>  
>      ::
>  
> -        -smp 16,sockets=2,dies=2,cores=2,threads=2,maxcpus=16
> +        -smp 32,sockets=2,dies=2,modules=2,cores=2,threads=2,maxcpus=32
>  
>      The following sub-option defines a CPU topology hierarchy (2 sockets
>      totally on the machine, 2 clusters per socket, 2 cores per cluster,

-- 
Thanks
Babu Moger