[PULL 31/43] hw/core/machine-smp: Deprecate unsupported "parameter=1" SMP configurations

From: Zhao Liu <zhao1.liu(a)intel.com&gt; Currently, it was allowed for users to specify the unsupported topology parameter as "1". For example, x86 PC machine doesn't support drawer/book/cluster topology levels, but user could specify "-smp drawers=1,books=1,clusters=1". This is meaningless and confusing, so that the support for this kind of configurations is marked deprecated since 9.0. And report warning message for such case like: qemu-system-x86_64: warning: Deprecated CPU topology (considered invalid): Unsupported clusters parameter mustn't be specified as 1 qemu-system-x86_64: warning: Deprecated CPU topology (considered invalid): Unsupported books parameter mustn't be specified as 1 qemu-system-x86_64: warning: Deprecated CPU topology (considered invalid): Unsupported drawers parameter mustn't be specified as 1 Users have to ensure that all the topology members described with -smp are supported by the target machine. Signed-off-by: Zhao Liu <zhao1.liu(a)intel.com&gt; Reviewed-by: Thomas Huth <thuth(a)redhat.com&gt; Message-ID: <20240308160148.3130837-3-zhao1.liu(a)linux.intel.com&gt; Signed-off-by: Philippe Mathieu-Daudé <philmd(a)linaro.org&gt; --- docs/about/deprecated.rst | 14 +++++++++ hw/core/machine-smp.c | 65 +++++++++++++++++++++++++++++---------- 2 files changed, 62 insertions(+), 17 deletions(-) diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst index 6e2f557682..dfd681cd02 100644 --- a/docs/about/deprecated.rst +++ b/docs/about/deprecated.rst @@ -57,6 +57,20 @@ The ``-p`` option pretends to control the host page size. However, it is not possible to change the host page size, and using the option only causes failures. +``-smp`` (Unsupported "parameter=1" SMP configurations) (since 9.0) +''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' + +Specified CPU topology parameters must be supported by the machine. + +In the SMP configuration, users should provide the CPU topology parameters that +are supported by the target machine. + +However, historically it was allowed for users to specify the unsupported +topology parameter as "1", which is meaningless. So support for this kind of +configurations (e.g. -smp drawers=1,books=1,clusters=1 for x86 PC machine) is +marked deprecated since 9.0, users have to ensure that all the topology members +described with -smp are supported by the target machine. + QEMU Machine Protocol (QMP) commands ------------------------------------ diff --git a/hw/core/machine-smp.c b/hw/core/machine-smp.c index 96533886b1..50a5a40dbc 100644 --- a/hw/core/machine-smp.c +++ b/hw/core/machine-smp.c @@ -112,30 +112,61 @@ void machine_parse_smp_config(MachineState *ms, /* * If not supported by the machine, a topology parameter must be - * omitted or specified equal to 1. + * omitted. */ - if (!mc->smp_props.dies_supported && dies > 1) { - error_setg(errp, "dies not supported by this machine's CPU topology"); - return; + if (!mc->smp_props.clusters_supported && config->has_clusters) { + if (config->clusters > 1) { + error_setg(errp, "clusters not supported by this " + "machine's CPU topology"); + return; + } else { + /* Here clusters only equals 1 since we've checked zero case. */ + warn_report("Deprecated CPU topology (considered invalid): " + "Unsupported clusters parameter mustn't be " + "specified as 1"); + } } - if (!mc->smp_props.clusters_supported && clusters > 1) { - error_setg(errp, "clusters not supported by this machine's CPU topology"); - return; - } - - dies = dies > 0 ? dies : 1; clusters = clusters > 0 ? clusters : 1; - if (!mc->smp_props.books_supported && books > 1) { - error_setg(errp, "books not supported by this machine's CPU topology"); - return; + if (!mc->smp_props.dies_supported && config->has_dies) { + if (config->dies > 1) { + error_setg(errp, "dies not supported by this " + "machine's CPU topology"); + return; + } else { + /* Here dies only equals 1 since we've checked zero case. */ + warn_report("Deprecated CPU topology (considered invalid): " + "Unsupported dies parameter mustn't be " + "specified as 1"); + } + } + dies = dies > 0 ? dies : 1; + + if (!mc->smp_props.books_supported && config->has_books) { + if (config->books > 1) { + error_setg(errp, "books not supported by this " + "machine's CPU topology"); + return; + } else { + /* Here books only equals 1 since we've checked zero case. */ + warn_report("Deprecated CPU topology (considered invalid): " + "Unsupported books parameter mustn't be " + "specified as 1"); + } } books = books > 0 ? books : 1; - if (!mc->smp_props.drawers_supported && drawers > 1) { - error_setg(errp, - "drawers not supported by this machine's CPU topology"); - return; + if (!mc->smp_props.drawers_supported && config->has_drawers) { + if (config->drawers > 1) { + error_setg(errp, "drawers not supported by this " + "machine's CPU topology"); + return; + } else { + /* Here drawers only equals 1 since we've checked zero case. */ + warn_report("Deprecated CPU topology (considered invalid): " + "Unsupported drawers parameter mustn't be " + "specified as 1"); + } } drawers = drawers > 0 ? drawers : 1; -- 2.41.0