On Wed, Jul 28, 2021 at 11:48:46AM +0800, Yanan Wang wrote: > 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 <drjo...@redhat.com> > Signed-off-by: Yanan Wang <wangyana...@huawei.com> > --- > hw/core/machine.c | 96 +++++++++++++++++++++++++++++++++++++++------ > hw/i386/pc.c | 83 +-------------------------------------- > include/hw/boards.h | 9 +++++ > 3 files changed, 93 insertions(+), 95 deletions(-) > > diff --git a/hw/core/machine.c b/hw/core/machine.c > index 9223ece3ea..76b6c3bc64 100644 > --- a/hw/core/machine.c > +++ b/hw/core/machine.c > @@ -15,6 +15,7 @@ > #include "qapi/qmp/qerror.h" > #include "sysemu/replay.h" > #include "qemu/units.h" > +#include "qemu/cutils.h" > #include "hw/boards.h" > #include "hw/loader.h" > #include "qapi/error.h" > @@ -744,20 +745,87 @@ void machine_set_cpu_numa_node(MachineState *machine, > } > } > > +static char *cpu_topology_hierarchy(MachineState *ms) > +{ > + MachineClass *mc = MACHINE_GET_CLASS(ms); > + SMPCompatProps *smp_props = &mc->smp_props; > + char topo_msg[256] = ""; > + > + /* > + * Topology members should be ordered from the largest to the smallest. > + * Concept of sockets/cores/threads is supported by default and will be > + * reported in the hierarchy. Unsupported members will not be reported. > + */ > + g_autofree char *sockets_msg = g_strdup_printf( > + " * sockets (%u)", ms->smp.sockets); > + pstrcat(topo_msg, sizeof(topo_msg), sockets_msg); > + > + if (smp_props->dies_supported) { > + g_autofree char *dies_msg = g_strdup_printf( > + " * dies (%u)", ms->smp.dies); > + pstrcat(topo_msg, sizeof(topo_msg), dies_msg); > + } > + > + g_autofree char *cores_msg = g_strdup_printf( > + " * cores (%u)", ms->smp.cores); > + pstrcat(topo_msg, sizeof(topo_msg), cores_msg); > + > + g_autofree char *threads_msg = g_strdup_printf( > + " * threads (%u)", ms->smp.threads); > + pstrcat(topo_msg, sizeof(topo_msg), threads_msg); > + > + return g_strdup_printf("%s", topo_msg + 3); > +} > + > +/* > + * smp_parse - Generic function used to parse the given SMP configuration > + * > + * A topology parameter must be omitted or specified equal to 1 if it's > + * not supported by the machine. Concept of sockets/cores/threads is > + * supported by default. Unsupported members will not be reported in > + * the cpu topology hierarchy message. > + * > + * For compatibility, if omitted the arch-specific members (e.g. dies) > + * will not be computed, but will directly default to 1 instead. This > + * logic should also apply to future introduced ones. > + * > + * Omitted arch-neutral members, i.e., cpus/sockets/cores/threads/maxcpus > + * will be computed based on the provided ones. 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. > + * > + * In 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. > + */ > 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) { > + /* > + * A topology parameter must be omitted or specified equal to 1, > + * if the machine's CPU topology doesn't support it. > + */ > + if (!mc->smp_props.dies_supported && dies > 1) { > error_setg(errp, "dies not supported by this machine's CPU > topology"); > return; > } > > + /* > + * If omitted the arch-specific members will not be computed, > + * but will directly default to 1 instead. > + */ > + dies = dies > 0 ? dies : 1; > + > /* compute missing values based on the provided ones */ > if (cpus == 0 && maxcpus == 0) { > sockets = sockets > 0 ? sockets : 1; > @@ -796,29 +864,31 @@ static void smp_parse(MachineState *ms, > SMPConfiguration *config, Error **errp) > maxcpus = maxcpus > 0 ? maxcpus : sockets * cores * threads; > cpus = cpus > 0 ? cpus : 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 * cores * threads != maxcpus) { > + g_autofree char *topo_msg = cpu_topology_hierarchy(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_topology_hierarchy(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, > diff --git a/hw/i386/pc.c b/hw/i386/pc.c > index 77ab764c5d..ce493a9294 100644 > --- a/hw/i386/pc.c > +++ b/hw/i386/pc.c > @@ -711,87 +711,6 @@ 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 over threads 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 if (threads == 0) { > - threads = maxcpus / (sockets * dies * cores); > - } > - } else { > - /* prefer cores over sockets over threads 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); > - } else if (threads == 0) { > - threads = maxcpus / (sockets * dies * cores); > - } > - } > - } > - > - maxcpus = maxcpus > 0 ? maxcpus : sockets * dies * cores * threads; > - cpus = cpus > 0 ? cpus : maxcpus; > - > - if (sockets * 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.maxcpus = maxcpus; > -} > - > static > void pc_machine_done(Notifier *notifier, void *data) > { > @@ -1745,7 +1664,6 @@ 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; > @@ -1756,6 +1674,7 @@ 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", > diff --git a/include/hw/boards.h b/include/hw/boards.h > index 2a1bba86c0..0631900c08 100644 > --- a/include/hw/boards.h > +++ b/include/hw/boards.h > @@ -108,6 +108,14 @@ typedef struct { > CPUArchId cpus[]; > } CPUArchIdList; > > +/** > + * SMPCompatProps: > + * @dies_supported - whether dies is 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, > -- > 2.19.1 >
What about putting smp_prefer_sockets in SMPCompatProps too (as prefer_sockets)? Otherwise Reviewed-by: Andrew Jones <drjo...@redhat.com>