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CPU topology: extend with s390 specifics

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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>
This commit is contained in:
Pierre Morel 2023-10-16 20:39:06 +02:00 • committed by Thomas Huth
parent 3da4aef81c
commit 5de1aff255
15 changed files with 141 additions and 13 deletions
Download patch file Download diff file Expand all files Collapse all files

48
hw/core/machine-smp.c
View file

@ -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: "