CPU topology: extend with s390 specifics

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.

Add the new levels to the relevant QAPI structs.
Add all the supported topology levels, dedication and entitlement
as properties to S390 CPUs.
Create machine-common.json so we can later include it in
machine-target.json also.

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>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Message-ID: <20231016183925.2384704-3-nsg@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

4 files changed, 62 insertions, 7 deletions

diff --git a/hw/core/machine-smp.c b/hw/core/machine-smp.c
index 0f4d9b6..25019c9 100644
--- a/hw/core/machine-smp.c
+++ b/hw/core/machine-smp.c
@@ -33,6 +33,14 @@ static char *cpu_hierarchy_to_string(MachineState *ms)
     MachineClass *mc = MACHINE_GET_CLASS(ms);
     GString *s = g_string_new(NULL);
 
+    if (mc->smp_props.drawers_supported) {
+        g_string_append_printf(s, "drawers (%u) * ", ms->smp.drawers);
+    }
+
+    if (mc->smp_props.books_supported) {
+        g_string_append_printf(s, "books (%u) * ", ms->smp.books);
+    }
+
     g_string_append_printf(s, "sockets (%u)", ms->smp.sockets);
 
     if (mc->smp_props.dies_supported) {
@@ -75,6 +83,8 @@ void machine_parse_smp_config(MachineState *ms,
 {
     MachineClass *mc = MACHINE_GET_CLASS(ms);
     unsigned cpus    = config->has_cpus ? config->cpus : 0;
+    unsigned drawers = config->has_drawers ? config->drawers : 0;
+    unsigned books   = config->has_books ? config->books : 0;
     unsigned sockets = config->has_sockets ? config->sockets : 0;
     unsigned dies    = config->has_dies ? config->dies : 0;
     unsigned clusters = config->has_clusters ? config->clusters : 0;
@@ -87,6 +97,8 @@ void machine_parse_smp_config(MachineState *ms,
      * explicit configuration like "cpus=0" is not allowed.
      */
     if ((config->has_cpus && config->cpus == 0) ||
+        (config->has_drawers && config->drawers == 0) ||
+        (config->has_books && config->books == 0) ||
         (config->has_sockets && config->sockets == 0) ||
         (config->has_dies && config->dies == 0) ||
         (config->has_clusters && config->clusters == 0) ||
@@ -113,6 +125,19 @@ void machine_parse_smp_config(MachineState *ms,
     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;
+    }
+    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;
+    }
+    drawers = drawers > 0 ? drawers : 1;
+
     /* compute missing values based on the provided ones */
     if (cpus == 0 && maxcpus == 0) {
         sockets = sockets > 0 ? sockets : 1;
@@ -126,33 +151,41 @@ void machine_parse_smp_config(MachineState *ms,
             if (sockets == 0) {
                 cores = cores > 0 ? cores : 1;
                 threads = threads > 0 ? threads : 1;
-                sockets = maxcpus / (dies * clusters * cores * threads);
+                sockets = maxcpus /
+                          (drawers * books * dies * clusters * cores * threads);
             } else if (cores == 0) {
                 threads = threads > 0 ? threads : 1;
-                cores = maxcpus / (sockets * dies * clusters * threads);
+                cores = maxcpus /
+                        (drawers * books * sockets * dies * clusters * threads);
             }
         } else {
             /* prefer cores over sockets since 6.2 */
             if (cores == 0) {
                 sockets = sockets > 0 ? sockets : 1;
                 threads = threads > 0 ? threads : 1;
-                cores = maxcpus / (sockets * dies * clusters * threads);
+                cores = maxcpus /
+                        (drawers * books * sockets * dies * clusters * threads);
             } else if (sockets == 0) {
                 threads = threads > 0 ? threads : 1;
-                sockets = maxcpus / (dies * clusters * cores * threads);
+                sockets = maxcpus /
+                          (drawers * books * dies * clusters * cores * threads);
             }
         }
 
         /* try to calculate omitted threads at last */
         if (threads == 0) {
-            threads = maxcpus / (sockets * dies * clusters * cores);
+            threads = maxcpus /
+                      (drawers * books * sockets * dies * clusters * cores);
         }
     }
 
-    maxcpus = maxcpus > 0 ? maxcpus : sockets * dies * clusters * cores * threads;
+    maxcpus = maxcpus > 0 ? maxcpus : drawers * books * sockets * dies *
+                                      clusters * cores * threads;
     cpus = cpus > 0 ? cpus : maxcpus;
 
     ms->smp.cpus = cpus;
+    ms->smp.drawers = drawers;
+    ms->smp.books = books;
     ms->smp.sockets = sockets;
     ms->smp.dies = dies;
     ms->smp.clusters = clusters;
@@ -163,7 +196,8 @@ void machine_parse_smp_config(MachineState *ms,
     mc->smp_props.has_clusters = config->has_clusters;
 
     /* sanity-check of the computed topology */
-    if (sockets * dies * clusters * cores * threads != maxcpus) {
+    if (drawers * books * sockets * dies * clusters * cores * threads !=
+        maxcpus) {
         g_autofree char *topo_msg = cpu_hierarchy_to_string(ms);
         error_setg(errp, "Invalid CPU topology: "
                    "product of the hierarchy must match maxcpus: "
diff --git a/hw/core/machine.c b/hw/core/machine.c
index 05aef2c..50edaab 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -863,6 +863,8 @@ static void machine_get_smp(Object *obj, Visitor *v, const char *name,
     MachineState *ms = MACHINE(obj);
     SMPConfiguration *config = &(SMPConfiguration){
         .has_cpus = true, .cpus = ms->smp.cpus,
+        .has_drawers = true, .drawers = ms->smp.drawers,
+        .has_books = true, .books = ms->smp.books,
         .has_sockets = true, .sockets = ms->smp.sockets,
         .has_dies = true, .dies = ms->smp.dies,
         .has_clusters = true, .clusters = ms->smp.clusters,
@@ -1137,6 +1139,8 @@ static void machine_initfn(Object *obj)
     /* default to mc->default_cpus */
     ms->smp.cpus = mc->default_cpus;
     ms->smp.max_cpus = mc->default_cpus;
+    ms->smp.drawers = 1;
+    ms->smp.books = 1;
     ms->smp.sockets = 1;
     ms->smp.dies = 1;
     ms->smp.clusters = 1;
diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c
index 6883406..7c6dfab 100644
--- a/hw/core/qdev-properties-system.c
+++ b/hw/core/qdev-properties-system.c
@@ -1139,3 +1139,16 @@ const PropertyInfo qdev_prop_uuid = {
     .set   = set_uuid,
     .set_default_value = set_default_uuid_auto,
 };
+
+/* --- s390 cpu entitlement policy --- */
+
+QEMU_BUILD_BUG_ON(sizeof(CpuS390Entitlement) != sizeof(int));
+
+const PropertyInfo qdev_prop_cpus390entitlement = {
+    .name  = "CpuS390Entitlement",
+    .description = "low/medium (default)/high",
+    .enum_table  = &CpuS390Entitlement_lookup,
+    .get   = qdev_propinfo_get_enum,
+    .set   = qdev_propinfo_set_enum,
+    .set_default_value = qdev_propinfo_set_default_value_enum,
+};
diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index 2d75f21..c1123a9 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -744,6 +744,8 @@ static void ccw_machine_class_init(ObjectClass *oc, void *data)
     mc->no_sdcard = 1;
     mc->max_cpus = S390_MAX_CPUS;
     mc->has_hotpluggable_cpus = true;
+    mc->smp_props.books_supported = true;
+    mc->smp_props.drawers_supported = true;
     assert(!mc->get_hotplug_handler);
     mc->get_hotplug_handler = s390_get_hotplug_handler;
     mc->cpu_index_to_instance_props = s390_cpu_index_to_props;
@@ -853,6 +855,8 @@ static void ccw_machine_8_1_class_options(MachineClass *mc)
 {
     ccw_machine_8_2_class_options(mc);
     compat_props_add(mc->compat_props, hw_compat_8_1, hw_compat_8_1_len);
+    mc->smp_props.drawers_supported = false;
+    mc->smp_props.books_supported = false;
 }
 DEFINE_CCW_MACHINE(8_1, "8.1", false);