diff options
Diffstat (limited to 'hw/core/machine.c')
| -rw-r--r-- | hw/core/machine.c | 199 |
1 files changed, 138 insertions, 61 deletions
diff --git a/hw/core/machine.c b/hw/core/machine.c index 067f42b528..3920a2f2af 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -746,64 +746,163 @@ 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 != 0 && config->dies != 1) { + /* + * Specified CPU topology parameters must be greater than zero, + * explicit configuration like "cpus=0" is not allowed. + */ + if ((config->has_cpus && config->cpus == 0) || + (config->has_sockets && config->sockets == 0) || + (config->has_dies && config->dies == 0) || + (config->has_cores && config->cores == 0) || + (config->has_threads && config->threads == 0) || + (config->has_maxcpus && config->maxcpus == 0)) { + warn_report("Deprecated CPU topology (considered invalid): " + "CPU topology parameters must be greater than zero"); + } + + /* + * 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; } - /* compute missing values, prefer sockets over cores over threads */ - if (cpus == 0 || sockets == 0) { + 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; - if (cpus == 0) { - sockets = sockets > 0 ? sockets : 1; - cpus = cores * threads * sockets; + } else { + maxcpus = maxcpus > 0 ? maxcpus : cpus; + + if (mc->smp_props.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 { - ms->smp.max_cpus = config->has_maxcpus ? config->maxcpus : cpus; - sockets = ms->smp.max_cpus / (cores * threads); + /* 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); } - } else if (cores == 0) { - threads = threads > 0 ? threads : 1; - cores = cpus / (sockets * threads); - cores = cores > 0 ? cores : 1; - } else if (threads == 0) { - threads = cpus / (cores * sockets); - threads = threads > 0 ? threads : 1; - } else if (sockets * cores * threads < cpus) { - error_setg(errp, "cpu topology: " - "sockets (%u) * cores (%u) * threads (%u) < " - "smp_cpus (%u)", - sockets, cores, threads, cpus); - return; } - ms->smp.max_cpus = config->has_maxcpus ? config->maxcpus : cpus; + maxcpus = maxcpus > 0 ? maxcpus : sockets * dies * 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; - if (ms->smp.max_cpus < cpus) { - error_setg(errp, "maxcpus must be equal to or greater than smp"); + /* 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: " + "%s != maxcpus (%u)", + topo_msg, maxcpus); return; } - if (sockets * cores * threads != ms->smp.max_cpus) { + if (maxcpus < cpus) { + g_autofree char *topo_msg = cpu_hierarchy_to_string(ms); error_setg(errp, "Invalid CPU topology: " - "sockets (%u) * cores (%u) * threads (%u) " - "!= maxcpus (%u)", - sockets, cores, threads, - ms->smp.max_cpus); + "maxcpus must be equal to or greater than smp: " + "%s == maxcpus (%u) < smp_cpus (%u)", + topo_msg, maxcpus, cpus); return; } - ms->smp.cpus = cpus; - ms->smp.cores = cores; - ms->smp.threads = threads; - ms->smp.sockets = sockets; + if (ms->smp.cpus < mc->min_cpus) { + error_setg(errp, "Invalid SMP CPUs %d. The min CPUs " + "supported by machine '%s' is %d", + ms->smp.cpus, + mc->name, mc->min_cpus); + return; + } + + if (ms->smp.max_cpus > mc->max_cpus) { + error_setg(errp, "Invalid SMP CPUs %d. The max CPUs " + "supported by machine '%s' is %d", + ms->smp.max_cpus, + mc->name, mc->max_cpus); + return; + } } static void machine_get_smp(Object *obj, Visitor *v, const char *name, @@ -811,11 +910,11 @@ static void machine_get_smp(Object *obj, Visitor *v, const char *name, { MachineState *ms = MACHINE(obj); SMPConfiguration *config = &(SMPConfiguration){ - .has_cores = true, .cores = ms->smp.cores, + .has_cpus = true, .cpus = ms->smp.cpus, .has_sockets = true, .sockets = ms->smp.sockets, .has_dies = true, .dies = ms->smp.dies, + .has_cores = true, .cores = ms->smp.cores, .has_threads = true, .threads = ms->smp.threads, - .has_cpus = true, .cpus = ms->smp.cpus, .has_maxcpus = true, .maxcpus = ms->smp.max_cpus, }; if (!visit_type_SMPConfiguration(v, name, &config, &error_abort)) { @@ -826,35 +925,14 @@ static void machine_get_smp(Object *obj, Visitor *v, const char *name, static void machine_set_smp(Object *obj, Visitor *v, const char *name, void *opaque, Error **errp) { - MachineClass *mc = MACHINE_GET_CLASS(obj); MachineState *ms = MACHINE(obj); - SMPConfiguration *config; - ERRP_GUARD(); + g_autoptr(SMPConfiguration) config = NULL; if (!visit_type_SMPConfiguration(v, name, &config, errp)) { return; } - mc->smp_parse(ms, config, errp); - if (*errp) { - goto out_free; - } - - /* sanity-check smp_cpus and max_cpus against mc */ - if (ms->smp.cpus < mc->min_cpus) { - error_setg(errp, "Invalid SMP CPUs %d. The min CPUs " - "supported by machine '%s' is %d", - ms->smp.cpus, - mc->name, mc->min_cpus); - } else if (ms->smp.max_cpus > mc->max_cpus) { - error_setg(errp, "Invalid SMP CPUs %d. The max CPUs " - "supported by machine '%s' is %d", - current_machine->smp.max_cpus, - mc->name, mc->max_cpus); - } - -out_free: - qapi_free_SMPConfiguration(config); + smp_parse(ms, config, errp); } static void machine_class_init(ObjectClass *oc, void *data) @@ -864,7 +942,6 @@ static void machine_class_init(ObjectClass *oc, void *data) /* Default 128 MB as guest ram size */ mc->default_ram_size = 128 * MiB; mc->rom_file_has_mr = true; - mc->smp_parse = smp_parse; /* numa node memory size aligned on 8MB by default. * On Linux, each node's border has to be 8MB aligned @@ -1028,10 +1105,10 @@ 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.cores = 1; + ms->smp.sockets = 1; ms->smp.dies = 1; + ms->smp.cores = 1; ms->smp.threads = 1; - ms->smp.sockets = 1; } static void machine_finalize(Object *obj) |