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machine: Make smp_parse generic enough for all arches

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Currently the only difference between smp_parse and pc_smp_parse
is the support of dies parameter and the related error reporting.
With some arch compat variables like "bool dies_supported", we can
make smp_parse generic enough for all arches and the PC specific
one can be removed.

Making smp_parse() generic enough can reduce code duplication and
ease the code maintenance, and also allows extending the topology
with more arch specific members (e.g., clusters) in the future.

Suggested-by: Andrew Jones <drjones@redhat.com>
Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210929025816.21076-13-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Yanan Wang 2021-09-29 10:58:12 +08:00 committed by Paolo Bonzini
parent 003f230e37
commit e4a97a893b
3 changed files with 81 additions and 103 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

91
hw/core/machine.c
View File

@ -746,20 +746,69 @@ void machine_set_cpu_numa_node(MachineState *machine,
}
}
/*
* Report information of a machine's supported CPU topology hierarchy.
* Topology members will be ordered from the largest to the smallest
* in the string.
*/
static char *cpu_hierarchy_to_string(MachineState *ms)
{
MachineClass *mc = MACHINE_GET_CLASS(ms);
GString *s = g_string_new(NULL);
g_string_append_printf(s, "sockets (%u)", ms->smp.sockets);
if (mc->smp_props.dies_supported) {
g_string_append_printf(s, " * dies (%u)", ms->smp.dies);
}
g_string_append_printf(s, " * cores (%u)", ms->smp.cores);
g_string_append_printf(s, " * threads (%u)", ms->smp.threads);
return g_string_free(s, false);
}
/*
* smp_parse - Generic function used to parse the given SMP configuration
*
* Any missing parameter in "cpus/maxcpus/sockets/cores/threads" will be
* automatically computed based on the provided ones.
*
* In the calculation of omitted sockets/cores/threads: we prefer sockets
* over cores over threads before 6.2, while preferring cores over sockets
* over threads since 6.2.
*
* In the calculation of cpus/maxcpus: When both maxcpus and cpus are omitted,
* maxcpus will be computed from the given parameters and cpus will be set
* equal to maxcpus. When only one of maxcpus and cpus is given then the
* omitted one will be set to its given counterpart's value. Both maxcpus and
* cpus may be specified, but maxcpus must be equal to or greater than cpus.
*
* For compatibility, apart from the parameters that will be computed, newly
* introduced topology members which are likely to be target specific should
* be directly set as 1 if they are omitted (e.g. dies for PC since 4.1).
*/
static void smp_parse(MachineState *ms, SMPConfiguration *config, Error **errp)
{
MachineClass *mc = MACHINE_GET_CLASS(ms);
unsigned cpus = config->has_cpus ? config->cpus : 0;
unsigned sockets = config->has_sockets ? config->sockets : 0;
unsigned dies = config->has_dies ? config->dies : 0;
unsigned cores = config->has_cores ? config->cores : 0;
unsigned threads = config->has_threads ? config->threads : 0;
unsigned maxcpus = config->has_maxcpus ? config->maxcpus : 0;
if (config->has_dies && config->dies > 1) {
/*
* If not supported by the machine, a topology parameter must be
* omitted or specified equal to 1.
*/
if (!mc->smp_props.dies_supported && dies > 1) {
error_setg(errp, "dies not supported by this machine's CPU topology");
return;
}
dies = dies > 0 ? dies : 1;
/* compute missing values based on the provided ones */
if (cpus == 0 && maxcpus == 0) {
sockets = sockets > 0 ? sockets : 1;
@ -773,55 +822,57 @@ static void smp_parse(MachineState *ms, SMPConfiguration *config, Error **errp)
if (sockets == 0) {
cores = cores > 0 ? cores : 1;
threads = threads > 0 ? threads : 1;
sockets = maxcpus / (cores * threads);
sockets = maxcpus / (dies * cores * threads);
} else if (cores == 0) {
threads = threads > 0 ? threads : 1;
cores = maxcpus / (sockets * threads);
cores = maxcpus / (sockets * dies * 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 * threads);
cores = maxcpus / (sockets * dies * threads);
} else if (sockets == 0) {
threads = threads > 0 ? threads : 1;
sockets = maxcpus / (cores * threads);
sockets = maxcpus / (dies * cores * threads);
}
}
/* try to calculate omitted threads at last */
if (threads == 0) {
threads = maxcpus / (sockets * cores);
threads = maxcpus / (sockets * dies * cores);
}
}
maxcpus = maxcpus > 0 ? maxcpus : sockets * cores * threads;
maxcpus = maxcpus > 0 ? maxcpus : sockets * dies * cores * threads;
cpus = cpus > 0 ? cpus : maxcpus;
if (sockets * cores * threads != maxcpus) {
ms->smp.cpus = cpus;
ms->smp.sockets = sockets;
ms->smp.dies = dies;
ms->smp.cores = cores;
ms->smp.threads = threads;
ms->smp.max_cpus = maxcpus;
/* sanity-check of the computed topology */
if (sockets * dies * 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: "
"sockets (%u) * cores (%u) * threads (%u) "
"!= maxcpus (%u)",
sockets, cores, threads, maxcpus);
"%s != maxcpus (%u)",
topo_msg, maxcpus);
return;
}
if (maxcpus < cpus) {
g_autofree char *topo_msg = cpu_hierarchy_to_string(ms);
error_setg(errp, "Invalid CPU topology: "
"maxcpus must be equal to or greater than smp: "
"sockets (%u) * cores (%u) * threads (%u) "
"== maxcpus (%u) < smp_cpus (%u)",
sockets, cores, threads, maxcpus, cpus);
"%s == maxcpus (%u) < smp_cpus (%u)",
topo_msg, maxcpus, cpus);
return;
}
ms->smp.cpus = cpus;
ms->smp.sockets = sockets;
ms->smp.cores = cores;
ms->smp.threads = threads;
ms->smp.max_cpus = maxcpus;
}
static void machine_get_smp(Object *obj, Visitor *v, const char *name,

84
hw/i386/pc.c
View File

@ -710,88 +710,6 @@ void pc_acpi_smi_interrupt(void *opaque, int irq, int level)
}
}
/*
* This function is very similar to smp_parse()
* in hw/core/machine.c but includes CPU die support.
*/
static void pc_smp_parse(MachineState *ms, SMPConfiguration *config, Error **errp)
{
MachineClass *mc = MACHINE_GET_CLASS(ms);
unsigned cpus = config->has_cpus ? config->cpus : 0;
unsigned sockets = config->has_sockets ? config->sockets : 0;
unsigned dies = config->has_dies ? config->dies : 0;
unsigned cores = config->has_cores ? config->cores : 0;
unsigned threads = config->has_threads ? config->threads : 0;
unsigned maxcpus = config->has_maxcpus ? config->maxcpus : 0;
/* directly default dies to 1 if it's omitted */
dies = dies > 0 ? dies : 1;
/* compute missing values based on the provided ones */
if (cpus == 0 && maxcpus == 0) {
sockets = sockets > 0 ? sockets : 1;
cores = cores > 0 ? cores : 1;
threads = threads > 0 ? threads : 1;
} else {
maxcpus = maxcpus > 0 ? maxcpus : cpus;
if (mc->smp_prefer_sockets) {
/* prefer sockets over cores before 6.2 */
if (sockets == 0) {
cores = cores > 0 ? cores : 1;
threads = threads > 0 ? threads : 1;
sockets = maxcpus / (dies * cores * threads);
} else if (cores == 0) {
threads = threads > 0 ? threads : 1;
cores = maxcpus / (sockets * dies * 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 * threads);
} else if (sockets == 0) {
threads = threads > 0 ? threads : 1;
sockets = maxcpus / (dies * cores * threads);
}
}
/* try to calculate omitted threads at last */
if (threads == 0) {
threads = maxcpus / (sockets * dies * cores);
}
}
maxcpus = maxcpus > 0 ? maxcpus : sockets * dies * cores * threads;
cpus = cpus > 0 ? cpus : maxcpus;
if (sockets * dies * cores * threads != maxcpus) {
error_setg(errp, "Invalid CPU topology: "
"product of the hierarchy must match maxcpus: "
"sockets (%u) * dies (%u) * cores (%u) * threads (%u) "
"!= maxcpus (%u)",
sockets, dies, cores, threads, maxcpus);
return;
}
if (maxcpus < cpus) {
error_setg(errp, "Invalid CPU topology: "
"maxcpus must be equal to or greater than smp: "
"sockets (%u) * dies (%u) * cores (%u) * threads (%u) "
"== maxcpus (%u) < smp_cpus (%u)",
sockets, dies, cores, threads, maxcpus, cpus);
return;
}
ms->smp.cpus = cpus;
ms->smp.sockets = sockets;
ms->smp.dies = dies;
ms->smp.cores = cores;
ms->smp.threads = threads;
ms->smp.max_cpus = maxcpus;
}
static
void pc_machine_done(Notifier *notifier, void *data)
{
@ -1755,7 +1673,6 @@ static void pc_machine_class_init(ObjectClass *oc, void *data)
mc->auto_enable_numa_with_memdev = true;
mc->has_hotpluggable_cpus = true;
mc->default_boot_order = "cad";
mc->smp_parse = pc_smp_parse;
mc->block_default_type = IF_IDE;
mc->max_cpus = 255;
mc->reset = pc_machine_reset;
@ -1766,6 +1683,7 @@ static void pc_machine_class_init(ObjectClass *oc, void *data)
hc->unplug = pc_machine_device_unplug_cb;
mc->default_cpu_type = TARGET_DEFAULT_CPU_TYPE;
mc->nvdimm_supported = true;
mc->smp_props.dies_supported = true;
mc->default_ram_id = "pc.ram";
object_class_property_add(oc, PC_MACHINE_MAX_RAM_BELOW_4G, "size",

9
include/hw/boards.h
View File

@ -108,6 +108,14 @@ typedef struct {
CPUArchId cpus[];
} CPUArchIdList;
/**
* SMPCompatProps:
* @dies_supported - whether dies are supported by the machine
*/
typedef struct {
bool dies_supported;
} SMPCompatProps;
/**
* MachineClass:
* @deprecation_reason: If set, the machine is marked as deprecated. The
@ -248,6 +256,7 @@ struct MachineClass {
bool numa_mem_supported;
bool auto_enable_numa;
bool smp_prefer_sockets;
SMPCompatProps smp_props;
const char *default_ram_id;
HotplugHandler *(*get_hotplug_handler)(MachineState *machine,