On Wed, Sep 02, 2026 at 07:15:39PM -0300, Fabiano Rosas wrote: > Change the hmp_migrate_set_parameter command to use a keyval input > visitor. > > Currently a string visitor is used and due to limitations of that > particular visitor's implementation it's necessary to consult the QAPI > type enum (MigrationParameter_lookup) and call each visit_type_* > function individually. Which makes using a visitor pointless. > > Since there are other visitors implemented properly and generated code > to iterate the QAPI object, prefer using one of those. The keyval > input visitor is adequate because HMP provides basically one key and > one value for each migrate_set_parameter command. > > To switch from string_input_visitor to keyval_input_visitor simply put > the parameter name and value into a dict and invoke > visit_type_MigrationParameters(). > > Note that it's not necessary to go through any of the keyval_* code > because due to the nature of HMP, there's no parsing to do (no '=', no > ',', etc). > > With this the migrate_set_parameters HMP commands will be > automatically updated anytime a new migration parameter is added. > > The bad part: > > Some parameters accept a non-standard data format, I moved them to a > "legacy" suffixed function in this patch as there's only 3 of them: > > - "max-bandwidth" and "avail-switchover-bandwidth" take MiB instead of B for > a size parameter;
Ah, I think it's only because I reused max-bandwidth unit there, but didn't reuse the same unit for max-postcopy-bandwidth at least.. IIUC, HMP ABI isn't guaranteed anyway, so I wonder if we can still remove these non-standard settings, maybe starting with some warning messages. Cc Dave. > > - "cpr-exec-command" takes the strList type which needs to be built > manually. > > Signed-off-by: Fabiano Rosas <[email protected]> > --- > migration/migration-hmp-cmds.c | 203 +++++++++-------------------- > tests/qtest/migration/misc-tests.c | 2 +- > 2 files changed, 59 insertions(+), 146 deletions(-) > > diff --git a/migration/migration-hmp-cmds.c b/migration/migration-hmp-cmds.c > index ad68fa23aa4..220ac28b5e3 100644 > --- a/migration/migration-hmp-cmds.c > +++ b/migration/migration-hmp-cmds.c > @@ -24,7 +24,9 @@ > #include "qapi/error.h" > #include "qapi/qapi-commands-migration.h" > #include "qapi/qapi-visit-migration.h" > +#include "qapi/qobject-input-visitor.h" > #include "qobject/qdict.h" > +#include "qobject/qstring.h" > #include "qapi/string-input-visitor.h" > #include "qapi/string-output-visitor.h" > #include "qemu/cutils.h" > @@ -589,59 +591,16 @@ end: > hmp_handle_error(mon, err); > } > > -void hmp_migrate_set_parameter(Monitor *mon, const QDict *qdict) > +static void hmp_migrate_set_parameter_legacy(Monitor *mon, const QDict > *qdict) > { > const char *param = qdict_get_str(qdict, "parameter"); > const char *valuestr = qdict_get_str(qdict, "value"); > - Visitor *v = string_input_visitor_new(valuestr); > MigrationParameters *p = g_new0(MigrationParameters, 1); > uint64_t valuebw = 0; > - uint64_t cache_size; > Error *err = NULL; > - int val, ret; > + int ret; > > - val = qapi_enum_parse(&MigrationParameter_lookup, param, -1, &err); > - if (val < 0) { > - goto cleanup; > - } > - > - switch (val) { > - case MIGRATION_PARAMETER_THROTTLE_TRIGGER_THRESHOLD: > - p->has_throttle_trigger_threshold = true; > - visit_type_uint8(v, param, &p->throttle_trigger_threshold, &err); > - break; > - case MIGRATION_PARAMETER_CPU_THROTTLE_INITIAL: > - p->has_cpu_throttle_initial = true; > - visit_type_uint8(v, param, &p->cpu_throttle_initial, &err); > - break; > - case MIGRATION_PARAMETER_CPU_THROTTLE_INCREMENT: > - p->has_cpu_throttle_increment = true; > - visit_type_uint8(v, param, &p->cpu_throttle_increment, &err); > - break; > - case MIGRATION_PARAMETER_CPU_THROTTLE_TAILSLOW: > - p->has_cpu_throttle_tailslow = true; > - visit_type_bool(v, param, &p->cpu_throttle_tailslow, &err); > - break; > - case MIGRATION_PARAMETER_MAX_CPU_THROTTLE: > - p->has_max_cpu_throttle = true; > - visit_type_uint8(v, param, &p->max_cpu_throttle, &err); > - break; > - case MIGRATION_PARAMETER_TLS_CREDS: > - p->tls_creds = g_new0(StrOrNull, 1); > - p->tls_creds->type = QTYPE_QSTRING; > - visit_type_str(v, param, &p->tls_creds->u.s, &err); > - break; > - case MIGRATION_PARAMETER_TLS_HOSTNAME: > - p->tls_hostname = g_new0(StrOrNull, 1); > - p->tls_hostname->type = QTYPE_QSTRING; > - visit_type_str(v, param, &p->tls_hostname->u.s, &err); > - break; > - case MIGRATION_PARAMETER_TLS_AUTHZ: > - p->tls_authz = g_new0(StrOrNull, 1); > - p->tls_authz->type = QTYPE_QSTRING; > - visit_type_str(v, param, &p->tls_authz->u.s, &err); > - break; > - case MIGRATION_PARAMETER_MAX_BANDWIDTH: > + if (g_str_equal(param, "max-bandwidth")) { > p->has_max_bandwidth = true; > /* > * Can't use visit_type_size() here, because it > @@ -651,109 +610,21 @@ void hmp_migrate_set_parameter(Monitor *mon, const > QDict *qdict) > if (ret < 0 || valuebw > INT64_MAX > || (size_t)valuebw != valuebw) { > error_setg(&err, "Invalid size %s", valuestr); > - break; > + return; This may leak @err and @p? > } > p->max_bandwidth = valuebw; > - break; > - case MIGRATION_PARAMETER_AVAIL_SWITCHOVER_BANDWIDTH: > + > + } else if (g_str_equal(param, "avail-switchover-bandwidth")) { > p->has_avail_switchover_bandwidth = true; > ret = qemu_strtosz_MiB(valuestr, NULL, &valuebw); > if (ret < 0 || valuebw > INT64_MAX > || (size_t)valuebw != valuebw) { > error_setg(&err, "Invalid size %s", valuestr); > - break; > + return; Same. > } > p->avail_switchover_bandwidth = valuebw; > - break; > - case MIGRATION_PARAMETER_DOWNTIME_LIMIT: > - p->has_downtime_limit = true; > - visit_type_size(v, param, &p->downtime_limit, &err); > - break; > - case MIGRATION_PARAMETER_X_CHECKPOINT_DELAY: > - p->has_x_checkpoint_delay = true; > - visit_type_uint32(v, param, &p->x_checkpoint_delay, &err); > - break; > - case MIGRATION_PARAMETER_MULTIFD_CHANNELS: > - p->has_multifd_channels = true; > - visit_type_uint8(v, param, &p->multifd_channels, &err); > - break; > - case MIGRATION_PARAMETER_MULTIFD_COMPRESSION: > - p->has_multifd_compression = true; > - visit_type_MultiFDCompression(v, param, &p->multifd_compression, > - &err); > - break; > - case MIGRATION_PARAMETER_MULTIFD_ZLIB_LEVEL: > - p->has_multifd_zlib_level = true; > - visit_type_uint8(v, param, &p->multifd_zlib_level, &err); > - break; > - case MIGRATION_PARAMETER_MULTIFD_QATZIP_LEVEL: > - p->has_multifd_qatzip_level = true; > - visit_type_uint8(v, param, &p->multifd_qatzip_level, &err); > - break; > - case MIGRATION_PARAMETER_MULTIFD_ZSTD_LEVEL: > - p->has_multifd_zstd_level = true; > - visit_type_uint8(v, param, &p->multifd_zstd_level, &err); > - break; > - case MIGRATION_PARAMETER_ZERO_PAGE_DETECTION: > - p->has_zero_page_detection = true; > - visit_type_ZeroPageDetection(v, param, &p->zero_page_detection, > &err); > - break; > - case MIGRATION_PARAMETER_XBZRLE_CACHE_SIZE: > - p->has_xbzrle_cache_size = true; > - if (!visit_type_size(v, param, &cache_size, &err)) { > - break; > - } > - if (cache_size > INT64_MAX || (size_t)cache_size != cache_size) { > - error_setg(&err, "Invalid size %s", valuestr); > - break; > - } > - p->xbzrle_cache_size = cache_size; > - break; > - case MIGRATION_PARAMETER_MAX_POSTCOPY_BANDWIDTH: > - p->has_max_postcopy_bandwidth = true; > - visit_type_size(v, param, &p->max_postcopy_bandwidth, &err); > - break; > - case MIGRATION_PARAMETER_ANNOUNCE_INITIAL: > - p->has_announce_initial = true; > - visit_type_size(v, param, &p->announce_initial, &err); > - break; > - case MIGRATION_PARAMETER_ANNOUNCE_MAX: > - p->has_announce_max = true; > - visit_type_size(v, param, &p->announce_max, &err); > - break; > - case MIGRATION_PARAMETER_ANNOUNCE_ROUNDS: > - p->has_announce_rounds = true; > - visit_type_size(v, param, &p->announce_rounds, &err); > - break; > - case MIGRATION_PARAMETER_ANNOUNCE_STEP: > - p->has_announce_step = true; > - visit_type_size(v, param, &p->announce_step, &err); > - break; > - case MIGRATION_PARAMETER_BLOCK_BITMAP_MAPPING: > - error_setg(&err, "The block-bitmap-mapping parameter can only be set > " > - "through QMP"); > - break; > - case MIGRATION_PARAMETER_X_VCPU_DIRTY_LIMIT_PERIOD: > - p->has_x_vcpu_dirty_limit_period = true; > - visit_type_size(v, param, &p->x_vcpu_dirty_limit_period, &err); > - break; > - case MIGRATION_PARAMETER_VCPU_DIRTY_LIMIT: > - p->has_vcpu_dirty_limit = true; > - visit_type_size(v, param, &p->vcpu_dirty_limit, &err); > - break; > - case MIGRATION_PARAMETER_MODE: > - p->has_mode = true; > - visit_type_MigMode(v, param, &p->mode, &err); > - break; > - case MIGRATION_PARAMETER_DIRECT_IO: > - p->has_direct_io = true; > - visit_type_bool(v, param, &p->direct_io, &err); > - break; > - case MIGRATION_PARAMETER_X_RDMA_CHUNK_SIZE: > - p->has_x_rdma_chunk_size = true; > - visit_type_size(v, param, &p->x_rdma_chunk_size, &err); > - break; > - case MIGRATION_PARAMETER_CPR_EXEC_COMMAND: { > + > + } else if (g_str_equal(param, "cpr-exec-command")) { > /* > * NOTE: g_autofree will only auto g_free() the strv array when > * needed, it will not free the strings within the array. It's > @@ -766,15 +637,14 @@ void hmp_migrate_set_parameter(Monitor *mon, const > QDict *qdict) > > if (!g_shell_parse_argv(valuestr, NULL, &strv, &gerr)) { > error_setg(&err, "%s", gerr->message); > - break; > + return; Same. > } > for (int i = 0; strv[i]; i++) { > QAPI_LIST_APPEND(tail, strv[i]); > } > p->has_cpr_exec_command = true; > - break; > - } > - default: > + > + } else { > g_assert_not_reached(); > } > > @@ -784,12 +654,55 @@ void hmp_migrate_set_parameter(Monitor *mon, const > QDict *qdict) > > qmp_migrate_set_parameters(p, &err); > > - cleanup: > +cleanup: > qapi_free_MigrationParameters(p); > + hmp_handle_error(mon, err); > +} > + > +static void hmp_migrate_set_parameter_qapi(Monitor *mon, const QDict *qdict) > +{ > + const char *param = qdict_get_str(qdict, "parameter"); > + const char *valuestr = qdict_get_str(qdict, "value"); > + g_autoptr(QDict) input = qdict_new(); > + g_autoptr(MigrationParameters) p = NULL; > + Visitor *v; > + Error *err = NULL; > + > + /* the same as keyval_parse(), but here there's no need to parse */ > + qdict_put_obj(input, param, QOBJECT(qstring_from_str(valuestr))); > + > + v = qobject_input_visitor_new_keyval(QOBJECT(input)); > + if (visit_type_MigrationParameters(v, NULL, &p, &err)) { > + qmp_migrate_set_parameters(p, &err); > + } > + > visit_free(v); > hmp_handle_error(mon, err); > } > > +void hmp_migrate_set_parameter(Monitor *mon, const QDict *qdict) > +{ > + const char *param = qdict_get_str(qdict, "parameter"); > + > + if (g_str_equal(param, "block-bitmap-mapping")) { > + Error *err = NULL; > + > + error_setg(&err, "The %s parameter can only be set through QMP", > param); > + hmp_handle_error(mon, err); > + return; > + } > + > + /* these have non-standard setters */ > + if (g_str_equal(param, "max-bandwidth") || > + g_str_equal(param, "avail-switchover-bandwidth") || > + g_str_equal(param, "cpr-exec-command")) { > + > + return hmp_migrate_set_parameter_legacy(mon, qdict); > + } > + > + hmp_migrate_set_parameter_qapi(mon, qdict); > +} > + > void hmp_migrate_start_postcopy(Monitor *mon, const QDict *qdict) > { > Error *err = NULL; > diff --git a/tests/qtest/migration/misc-tests.c > b/tests/qtest/migration/misc-tests.c > index 3554900b758..ba8183978b3 100644 > --- a/tests/qtest/migration/misc-tests.c > +++ b/tests/qtest/migration/misc-tests.c > @@ -48,7 +48,7 @@ typedef struct HMPTestData { > HMPTestData test_cases[] = { > TEST("", "", "migrate_set_parameter: string expected"), > TEST("foo", "", "migrate_set_parameter: string expected"), > - TEST("foo", "on", "Error: invalid parameter value: foo"), > + TEST("foo", "on", "Error: Parameter 'foo' is unexpected"), > > /* bool */ > TEST("cpu-throttle-tailslow", "on", "on"), > -- > 2.53.0 > -- Peter Xu
