On Wed, Sep 02, 2026 at 07:15:41PM -0300, Fabiano Rosas wrote: > The hmp_info_migrate_parameters function currently open-codes the > mon_printf calls for each migration parameter. As with the set command > in the last patch, this should not be necessary as the QAPI > infrastructure already has generated code that takes type and struct > member names into account, including converting _ from C into the '-' > character as part of parameter names strings. > > The current code is also quite painful to rebase if a series has been > carried for a long time while parameters have been added in master. > > Replace all of this with a conversion from MigrationParameters to > QDict using an output visitor and a loop over the QDict that prints > per-QAPI-type formatted strings. > > Modelled after block/qapi.c:dump_qobject, but with some changes to > keep the migration command output formatting. > > Note that this was not a for-free improvement, the HMP command format > output was changed incompatibly in a previous patch. It doesn't output > units anymore.
IIUC both qlist and qdict are only used in BitmapMigrationNodeAlias only. It would be nice to attach an example of HMP dump before/after the change of these two patches, either in previous patch or here (assuming the layout changed once). In case HMP has some suggestion in general, I suggest copy Dave when repost in case he has something to say. > > Signed-off-by: Fabiano Rosas <[email protected]> > --- > migration/migration-hmp-cmds.c | 243 ++++++++++++++------------------- > 1 file changed, 100 insertions(+), 143 deletions(-) > > diff --git a/migration/migration-hmp-cmds.c b/migration/migration-hmp-cmds.c > index 089c6d4ff46..dff69650a0c 100644 > --- a/migration/migration-hmp-cmds.c > +++ b/migration/migration-hmp-cmds.c > @@ -25,7 +25,12 @@ > #include "qapi/qapi-commands-migration.h" > #include "qapi/qapi-visit-migration.h" > #include "qapi/qobject-input-visitor.h" > +#include "qapi/qobject-output-visitor.h" > +#include "qobject/qbool.h" > #include "qobject/qdict.h" > +#include "qobject/qjson.h" > +#include "qobject/qlist.h" > +#include "qobject/qnum.h" > #include "qobject/qstring.h" > #include "qapi/string-input-visitor.h" > #include "qapi/string-output-visitor.h" > @@ -316,170 +321,122 @@ void hmp_info_migrate_capabilities(Monitor *mon, > const QDict *qdict) > qapi_free_MigrationCapabilityStatusList(caps); > } > > -static void monitor_print_cpr_exec_command(Monitor *mon, strList *args) > +static QDict *migrate_params_to_dict(MigrationParameters *p, Error **errp) > { > - monitor_printf(mon, "%s:", > - MigrationParameter_str(MIGRATION_PARAMETER_CPR_EXEC_COMMAND)); > + QObject *obj = NULL; > + Visitor *v = qobject_output_visitor_new(&obj); > > - while (args) { > - monitor_printf(mon, " %s", args->value); > - args = args->next; > + if (visit_type_MigrationParameters(v, NULL, &p, errp)) { > + visit_complete(v, &obj); > } > - monitor_printf(mon, "\n"); > + visit_free(v); > + return qobject_to(QDict, obj); > } This exact function also exists in options.c (with the same name and impl). Can reuse. > > -void hmp_info_migrate_parameters(Monitor *mon, const QDict *qdict) > +static void hmp_migrate_print_qobject(Monitor *mon, const char *label, > + QObject *obj) > { > - MigrationParameters *params; > - MigrationState *s = migrate_get_current(); > + const char *sep; > > - params = qmp_query_migrate_parameters(NULL); > + if (!obj) { > + return; > + } > > - if (params) { > - monitor_printf(mon, "%s: %" PRIu64 "\n", > - MigrationParameter_str(MIGRATION_PARAMETER_ANNOUNCE_INITIAL), > - params->announce_initial); > - monitor_printf(mon, "%s: %" PRIu64 "\n", > - MigrationParameter_str(MIGRATION_PARAMETER_ANNOUNCE_MAX), > - params->announce_max); > - monitor_printf(mon, "%s: %" PRIu64 "\n", > - MigrationParameter_str(MIGRATION_PARAMETER_ANNOUNCE_ROUNDS), > - params->announce_rounds); > - monitor_printf(mon, "%s: %" PRIu64 "\n", > - MigrationParameter_str(MIGRATION_PARAMETER_ANNOUNCE_STEP), > - params->announce_step); > - assert(params->has_throttle_trigger_threshold); > - monitor_printf(mon, "%s: %u\n", > - > MigrationParameter_str(MIGRATION_PARAMETER_THROTTLE_TRIGGER_THRESHOLD), > - params->throttle_trigger_threshold); > - assert(params->has_cpu_throttle_initial); > - monitor_printf(mon, "%s: %u\n", > - MigrationParameter_str(MIGRATION_PARAMETER_CPU_THROTTLE_INITIAL), > - params->cpu_throttle_initial); > - assert(params->has_cpu_throttle_increment); > - monitor_printf(mon, "%s: %u\n", > - > MigrationParameter_str(MIGRATION_PARAMETER_CPU_THROTTLE_INCREMENT), > - params->cpu_throttle_increment); > - assert(params->has_cpu_throttle_tailslow); > - monitor_printf(mon, "%s: %s\n", > - > MigrationParameter_str(MIGRATION_PARAMETER_CPU_THROTTLE_TAILSLOW), > - params->cpu_throttle_tailslow ? "on" : "off"); > - assert(params->has_max_cpu_throttle); > - monitor_printf(mon, "%s: %u\n", > - MigrationParameter_str(MIGRATION_PARAMETER_MAX_CPU_THROTTLE), > - params->max_cpu_throttle); > - assert(params->tls_creds); > - monitor_printf(mon, "%s: %s\n", > - MigrationParameter_str(MIGRATION_PARAMETER_TLS_CREDS), > - params->tls_creds->u.s); > - assert(params->tls_hostname); > - monitor_printf(mon, "%s: %s\n", > - MigrationParameter_str(MIGRATION_PARAMETER_TLS_HOSTNAME), > - params->tls_hostname->u.s); > - assert(params->tls_authz); > - monitor_printf(mon, "%s: %s\n", > - MigrationParameter_str(MIGRATION_PARAMETER_TLS_AUTHZ), > - params->tls_authz->u.s); > - assert(params->has_max_bandwidth); > - monitor_printf(mon, "%s: %" PRIu64 "\n", > - MigrationParameter_str(MIGRATION_PARAMETER_MAX_BANDWIDTH), > - params->max_bandwidth); > - assert(params->has_avail_switchover_bandwidth); > - monitor_printf(mon, "%s: %" PRIu64 "\n", > - > MigrationParameter_str(MIGRATION_PARAMETER_AVAIL_SWITCHOVER_BANDWIDTH), > - params->avail_switchover_bandwidth); > - assert(params->has_max_postcopy_bandwidth); > - monitor_printf(mon, "%s: %" PRIu64 "\n", > - > MigrationParameter_str(MIGRATION_PARAMETER_MAX_POSTCOPY_BANDWIDTH), > - params->max_postcopy_bandwidth); > - assert(params->has_downtime_limit); > - monitor_printf(mon, "%s: %" PRIu64 "\n", > - MigrationParameter_str(MIGRATION_PARAMETER_DOWNTIME_LIMIT), > - params->downtime_limit); > - assert(params->has_x_checkpoint_delay); > - monitor_printf(mon, "%s: %u\n", > - MigrationParameter_str(MIGRATION_PARAMETER_X_CHECKPOINT_DELAY), > - params->x_checkpoint_delay); > - monitor_printf(mon, "%s: %u\n", > - MigrationParameter_str(MIGRATION_PARAMETER_MULTIFD_CHANNELS), > - params->multifd_channels); > - monitor_printf(mon, "%s: %s\n", > - MigrationParameter_str(MIGRATION_PARAMETER_MULTIFD_COMPRESSION), > - MultiFDCompression_str(params->multifd_compression)); > - assert(params->has_zero_page_detection); > - monitor_printf(mon, "%s: %s\n", > - MigrationParameter_str(MIGRATION_PARAMETER_ZERO_PAGE_DETECTION), > - qapi_enum_lookup(&ZeroPageDetection_lookup, > - params->zero_page_detection)); > - monitor_printf(mon, "%s: %" PRIu64 "\n", > - MigrationParameter_str(MIGRATION_PARAMETER_XBZRLE_CACHE_SIZE), > - params->xbzrle_cache_size); > + /* > + * Put a space after labels > + * foo: bar > + * ^ > + */ > + if (label && label[0] && label[strlen(label) - 1] == ':') { > + sep = " "; > + } else { > + sep = ""; > + } > > - if (s->has_block_bitmap_mapping) { > - BitmapMigrationNodeAliasList *nal; > - BitmapMigrationNodeAlias *na; > - BitmapMigrationBitmapAliasList *bal; > - BitmapMigrationBitmapAlias *ba; > - BitmapMigrationBitmapAliasTransform *bat; > + switch (qobject_type(obj)) { > + case QTYPE_NONE: > + g_assert_not_reached(); > + case QTYPE_QNULL: > + break; Shall we assert too if we don't expect it? > + case QTYPE_QNUM: { > + int64_t i64; > > - monitor_printf(mon, "%s:", > - MigrationParameter_str( > - MIGRATION_PARAMETER_BLOCK_BITMAP_MAPPING)); > + if (qnum_get_try_int(qobject_to(QNum, obj), &i64)) { > + monitor_printf(mon, "%s%s%" PRId64, label, sep, i64); Should we use qnum_to_string() like what dump_qobject() does? Logically any size/u64 parameter (which may not be a normal use case..) can be set larger than INT64_MAX, so qnum_get_try_int() may return false? Here skipping to print anything is benign if it only happens with a malicious monitor client, but I think we should try to capture all cases. > + } > + break; > + } > + case QTYPE_QSTRING: { > + QString *str = qobject_to(QString, obj); > > - for (nal = params->block_bitmap_mapping; nal; nal = nal->next) > - { > - na = nal->value; > - monitor_printf(mon, " bitmaps:"); > - for (bal = na->bitmaps; bal; bal = bal->next) { > - ba = bal->value; > - bat = ba->transform; > + if (str) { Any chance str==NULL here? > + monitor_printf(mon, "%s%s%s", label, sep, qstring_get_str(str)); > + } > + break; > + } > + case QTYPE_QDICT: { > + QDict *d = qobject_to(QDict, obj); > + const QDictEntry *e; > + int i = 0; > > - monitor_printf(mon, " name: %s", ba->name); > - if (bat && bat->has_persistent) { > - if (bat->persistent) { > - monitor_printf(mon, " persistent: on"); > - } else { > - monitor_printf(mon, " persistent: off"); > - } > - } > - monitor_printf(mon, " alias: %s", ba->alias); > + if (d) { > + for (e = qdict_first(d); e; e = qdict_next(d, e), i++) { > + g_autofree char *l = g_strdup_printf("%s:", > qdict_entry_key(e)); > + if (i) { > + monitor_printf(mon, " "); > } > - monitor_printf(mon, " node-name: %s alias: %s", > - na->node_name, na->alias); > + hmp_migrate_print_qobject(mon, l, qdict_entry_value(e)); > } > - > - monitor_printf(mon, "\n"); > } > + break; > + } > + case QTYPE_QLIST: { > + QList *l = qobject_to(QList, obj); > + const QListEntry *e; > > - monitor_printf(mon, "%s: %" PRIu64 "\n", > - > MigrationParameter_str(MIGRATION_PARAMETER_X_VCPU_DIRTY_LIMIT_PERIOD), > - params->x_vcpu_dirty_limit_period); > + if (l) { > + monitor_printf(mon, "%s", label); > > - monitor_printf(mon, "%s: %" PRIu64 "\n", > - MigrationParameter_str(MIGRATION_PARAMETER_VCPU_DIRTY_LIMIT), > - params->vcpu_dirty_limit); > + for (e = qlist_first(l); e; e = qlist_next(e)) { > + /* > + * In the first iteration, this is the space after the > + * colon, otherwise it's the space between list > + * elements. > + */ > + monitor_printf(mon, " "); > + hmp_migrate_print_qobject(mon, "", e->value); > + } > + } > + break; > + } > + case QTYPE_QBOOL: { > + QBool *b = qobject_to(QBool, obj); > + if (b) { Similarly, I'd drop "if" if it will always happen, making qbool_get_bool() assert itself by deref. > + monitor_printf(mon, "%s%s%s", label, sep, > + qbool_get_bool(b) ? "on" : "off"); > + } > + break; > + } > + default: > + g_assert_not_reached(); > + break; > + } > +} > > - assert(params->has_mode); > - monitor_printf(mon, "%s: %s\n", > - MigrationParameter_str(MIGRATION_PARAMETER_MODE), > - qapi_enum_lookup(&MigMode_lookup, params->mode)); > +void hmp_info_migrate_parameters(Monitor *mon, const QDict *qdict) > +{ > + MigrationParameters *params = qmp_query_migrate_parameters(NULL); > + g_autoptr(QDict) d; > + const QDictEntry *e; > > - if (params->has_direct_io) { > - monitor_printf(mon, "%s: %s\n", > - MigrationParameter_str( > - MIGRATION_PARAMETER_DIRECT_IO), > - params->direct_io ? "on" : "off"); > - } > + assert(params); > > - if (params->has_x_rdma_chunk_size) { > - monitor_printf(mon, "%s: %" PRIu64 "\n", > - MigrationParameter_str( > - MIGRATION_PARAMETER_X_RDMA_CHUNK_SIZE), > - params->x_rdma_chunk_size); > - } > + d = migrate_params_to_dict(params, NULL); > + for (e = qdict_first(d); e; e = qdict_next(d, e)) { > + g_autofree char *label = g_strdup_printf("%s:", qdict_entry_key(e)); > > - assert(params->has_cpr_exec_command); > - monitor_print_cpr_exec_command(mon, params->cpr_exec_command); > + hmp_migrate_print_qobject(mon, label, qdict_entry_value(e)); > + monitor_printf(mon, "\n"); > } > > qapi_free_MigrationParameters(params); > -- > 2.53.0 > -- Peter Xu
