Re: [Qemu-devel] [v5 12/12] migration: Add commands to set and query parameter

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Liang Li (liang.z.li@intel.com) wrote:
> Add the qmp and hmp commands to tune and query the parameters used in
> live migration.
> 
> Signed-off-by: Liang Li <liang.z.li@intel.com>
> Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>

Hi,
   You might like to split this patch into two; one with no actual
parameters in the lists, and then a second one that adds your
compression options.

Dave

> ---
>  hmp-commands.hx               | 17 ++++++++
>  hmp.c                         | 56 +++++++++++++++++++++++++
>  hmp.h                         |  4 ++
>  include/migration/migration.h |  4 +-
>  migration/migration.c         | 96 +++++++++++++++++++++++++++++++++++++------
>  monitor.c                     | 25 +++++++++++
>  qapi-schema.json              | 86 ++++++++++++++++++++++++++++++++++++++
>  qmp-commands.hx               | 66 +++++++++++++++++++++++++++++
>  8 files changed, 339 insertions(+), 15 deletions(-)
> 
> diff --git a/hmp-commands.hx b/hmp-commands.hx
> index e37bc8b..ed0c06a 100644
> --- a/hmp-commands.hx
> +++ b/hmp-commands.hx
> @@ -985,6 +985,21 @@ Enable/Disable the usage of a capability @var{capability} for migration.
>  ETEXI
>  
>      {
> +        .name       = "migrate_set_parameter",
> +        .args_type  = "parameter:s,value:i",
> +        .params     = "parameter value",
> +        .help       = "Set the parameter for migration",
> +        .mhandler.cmd = hmp_migrate_set_parameter,
> +        .command_completion = migrate_set_parameter_completion,
> +    },
> +
> +STEXI
> +@item migrate_set_parameter @var{parameter} @var{value}
> +@findex migrate_set_parameter
> +Set the parameter @var{parameter} for migration.
> +ETEXI
> +
> +    {
>          .name       = "client_migrate_info",
>          .args_type  = "protocol:s,hostname:s,port:i?,tls-port:i?,cert-subject:s?",
>          .params     = "protocol hostname port tls-port cert-subject",
> @@ -1764,6 +1779,8 @@ show user network stack connection states
>  show migration status
>  @item info migrate_capabilities
>  show current migration capabilities
> +@item info migrate_parameters
> +show current migration parameters
>  @item info migrate_cache_size
>  show current migration XBZRLE cache size
>  @item info balloon
> diff --git a/hmp.c b/hmp.c
> index b47f331..1f67651 100644
> --- a/hmp.c
> +++ b/hmp.c
> @@ -246,6 +246,27 @@ void hmp_info_migrate_capabilities(Monitor *mon, const QDict *qdict)
>      qapi_free_MigrationCapabilityStatusList(caps);
>  }
>  
> +void hmp_info_migrate_parameters(Monitor *mon, const QDict *qdict)
> +{
> +    MigrationParameterStatusList *params, *p;
> +    MigrationParameterInt *data;
> +
> +    params = qmp_query_migrate_parameters(NULL);
> +
> +    if (params) {
> +        monitor_printf(mon, "parameters:");
> +        for (p = params; p; p = p->next) {
> +            data = (MigrationParameterInt *)p->value->data;
> +            monitor_printf(mon, " %s: %" PRId64,
> +                           MigrationParameter_lookup[p->value->kind],
> +                           data->value);
> +        }
> +        monitor_printf(mon, "\n");
> +    }
> +
> +    qapi_free_MigrationParameterStatusList(params);
> +}
> +
>  void hmp_info_migrate_cache_size(Monitor *mon, const QDict *qdict)
>  {
>      monitor_printf(mon, "xbzrel cache size: %" PRId64 " kbytes\n",
> @@ -1140,6 +1161,41 @@ void hmp_migrate_set_capability(Monitor *mon, const QDict *qdict)
>      }
>  }
>  
> +void hmp_migrate_set_parameter(Monitor *mon, const QDict *qdict)
> +{
> +    const char *param = qdict_get_str(qdict, "parameter");
> +    int value = qdict_get_int(qdict, "value");
> +    Error *err = NULL;
> +    MigrationParameterStatusList *params = g_malloc0(sizeof(*params));
> +    MigrationParameterInt *data;
> +    int i;
> +
> +    for (i = 0; i < MIGRATION_PARAMETER_MAX; i++) {
> +        if (strcmp(param, MigrationParameter_lookup[i]) == 0) {
> +            params->value = g_malloc0(sizeof(*params->value));
> +            params->value->kind = i;
> +            params->value->data = g_malloc0(sizeof(MigrationParameterInt));
> +            data = (MigrationParameterInt *)params->value->data;
> +            data->value = value;
> +            params->next = NULL;
> +            qmp_migrate_set_parameters(params, &err);
> +            break;
> +        }
> +    }
> +
> +    if (i == MIGRATION_PARAMETER_MAX) {
> +        error_set(&err, QERR_INVALID_PARAMETER, param);
> +    }
> +
> +    qapi_free_MigrationParameterStatusList(params);
> +
> +    if (err) {
> +        monitor_printf(mon, "migrate_set_parameter: %s\n",
> +                       error_get_pretty(err));
> +        error_free(err);
> +    }
> +}
> +
>  void hmp_set_password(Monitor *mon, const QDict *qdict)
>  {
>      const char *protocol  = qdict_get_str(qdict, "protocol");
> diff --git a/hmp.h b/hmp.h
> index 4bb5dca..b2b2d2c 100644
> --- a/hmp.h
> +++ b/hmp.h
> @@ -28,6 +28,7 @@ void hmp_info_chardev(Monitor *mon, const QDict *qdict);
>  void hmp_info_mice(Monitor *mon, const QDict *qdict);
>  void hmp_info_migrate(Monitor *mon, const QDict *qdict);
>  void hmp_info_migrate_capabilities(Monitor *mon, const QDict *qdict);
> +void hmp_info_migrate_parameters(Monitor *mon, const QDict *qdict);
>  void hmp_info_migrate_cache_size(Monitor *mon, const QDict *qdict);
>  void hmp_info_cpus(Monitor *mon, const QDict *qdict);
>  void hmp_info_block(Monitor *mon, const QDict *qdict);
> @@ -63,6 +64,7 @@ void hmp_migrate_cancel(Monitor *mon, const QDict *qdict);
>  void hmp_migrate_set_downtime(Monitor *mon, const QDict *qdict);
>  void hmp_migrate_set_speed(Monitor *mon, const QDict *qdict);
>  void hmp_migrate_set_capability(Monitor *mon, const QDict *qdict);
> +void hmp_migrate_set_parameter(Monitor *mon, const QDict *qdict);
>  void hmp_migrate_set_cache_size(Monitor *mon, const QDict *qdict);
>  void hmp_set_password(Monitor *mon, const QDict *qdict);
>  void hmp_expire_password(Monitor *mon, const QDict *qdict);
> @@ -111,6 +113,8 @@ void watchdog_action_completion(ReadLineState *rs, int nb_args,
>                                  const char *str);
>  void migrate_set_capability_completion(ReadLineState *rs, int nb_args,
>                                         const char *str);
> +void migrate_set_parameter_completion(ReadLineState *rs, int nb_args,
> +                                      const char *str);
>  void host_net_add_completion(ReadLineState *rs, int nb_args, const char *str);
>  void host_net_remove_completion(ReadLineState *rs, int nb_args,
>                                  const char *str);
> diff --git a/include/migration/migration.h b/include/migration/migration.h
> index 9ac1b23..434cc96 100644
> --- a/include/migration/migration.h
> +++ b/include/migration/migration.h
> @@ -51,9 +51,7 @@ struct MigrationState
>      QEMUBH *cleanup_bh;
>      QEMUFile *file;
>      QemuThread *compress_thread;
> -    int compress_thread_count;
> -    int decompress_thread_count;
> -    int compress_level;
> +    int parameters[MIGRATION_PARAMETER_MAX];
>  
>      int state;
>      MigrationParams params;
> diff --git a/migration/migration.c b/migration/migration.c
> index 55f749e..89750ba 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -66,9 +66,12 @@ MigrationState *migrate_get_current(void)
>          .bandwidth_limit = MAX_THROTTLE,
>          .xbzrle_cache_size = DEFAULT_MIGRATE_CACHE_SIZE,
>          .mbps = -1,
> -        .compress_thread_count = DEFAULT_MIGRATE_COMPRESS_THREAD_COUNT,
> -        .decompress_thread_count = DEFAULT_MIGRATE_DECOMPRESS_THREAD_COUNT,
> -        .compress_level = DEFAULT_MIGRATE_COMPRESS_LEVEL,
> +        .parameters[MIGRATION_PARAMETER_COMPRESS_LEVEL] =
> +                DEFAULT_MIGRATE_COMPRESS_LEVEL,
> +        .parameters[MIGRATION_PARAMETER_COMPRESS_THREADS] =
> +                DEFAULT_MIGRATE_COMPRESS_THREAD_COUNT,
> +        .parameters[MIGRATION_PARAMETER_DECOMPRESS_THREADS] =
> +                DEFAULT_MIGRATE_DECOMPRESS_THREAD_COUNT,
>      };
>  
>      return &current_migration;
> @@ -178,6 +181,33 @@ MigrationCapabilityStatusList *qmp_query_migrate_capabilities(Error **errp)
>      return head;
>  }
>  
> +MigrationParameterStatusList *qmp_query_migrate_parameters(Error **errp)
> +{
> +    MigrationParameterStatusList *head = NULL;
> +    MigrationParameterStatusList *params;
> +    MigrationState *s = migrate_get_current();
> +    MigrationParameterInt *data;
> +    int i;
> +
> +    params = NULL; /* silence compiler warning */
> +    for (i = 0; i < MIGRATION_PARAMETER_MAX; i++) {
> +        if (head == NULL) {
> +            head = g_malloc0(sizeof(*params));
> +            params = head;
> +        } else {
> +            params->next = g_malloc0(sizeof(*params));
> +            params = params->next;
> +        }
> +        params->value = g_malloc(sizeof(*params->value));
> +        params->value->kind = i;
> +        params->value->data = g_malloc(sizeof(MigrationParameterInt));
> +        data = (MigrationParameterInt *)params->value->data;
> +        data->value = s->parameters[i];
> +    }
> +
> +    return head;
> +}
> +
>  static void get_xbzrle_cache_stats(MigrationInfo *info)
>  {
>      if (migrate_use_xbzrle()) {
> @@ -294,6 +324,44 @@ void qmp_migrate_set_capabilities(MigrationCapabilityStatusList *params,
>      }
>  }
>  
> +void qmp_migrate_set_parameters(MigrationParameterStatusList *params,
> +                                Error **errp)
> +{
> +    MigrationState *s = migrate_get_current();
> +    MigrationParameterStatusList *p;
> +    MigrationParameterInt *data;
> +
> +    for (p = params; p; p = p->next) {
> +        switch (p->value->kind) {
> +        case MIGRATION_PARAMETER_COMPRESS_LEVEL:
> +            data = (MigrationParameterInt *)p->value->data;
> +            if (data->value < 0 || data->value > 9) {
> +                error_set(errp, QERR_INVALID_PARAMETER_VALUE, "compress_level",
> +                          "is invalid, it should be in the range of 0 to 9");
> +                return;
> +            }
> +            break;
> +        case MIGRATION_PARAMETER_COMPRESS_THREADS:
> +        case MIGRATION_PARAMETER_DECOMPRESS_THREADS:
> +            if (s->state == MIG_STATE_ACTIVE || s->state == MIG_STATE_SETUP) {
> +                error_set(errp, QERR_MIGRATION_ACTIVE);
> +                return;
> +            }
> +            data = (MigrationParameterInt *)p->value->data;
> +            if (data->value < 1 || data->value > 255) {
> +                error_set(errp, QERR_INVALID_PARAMETER_VALUE,
> +                          "(de)compress_threads",
> +                          "is invalid, it should be in the range of 1 to 255");
> +                return;
> +            }
> +            break;
> +        default:
> +           return;
> +        }
> +        s->parameters[p->value->kind] = data->value;
> +    }
> +}
> +
>  /* shared migration helpers */
>  
>  static void migrate_set_state(MigrationState *s, int old_state, int new_state)
> @@ -400,9 +468,11 @@ static MigrationState *migrate_init(const MigrationParams *params)
>      int64_t bandwidth_limit = s->bandwidth_limit;
>      bool enabled_capabilities[MIGRATION_CAPABILITY_MAX];
>      int64_t xbzrle_cache_size = s->xbzrle_cache_size;
> -    int compress_level = s->compress_level;
> -    int compress_thread_count = s->compress_thread_count;
> -    int decompress_thread_count = s->decompress_thread_count;
> +    int compress_level = s->parameters[MIGRATION_PARAMETER_COMPRESS_LEVEL];
> +    int compress_thread_count =
> +            s->parameters[MIGRATION_PARAMETER_COMPRESS_THREADS];
> +    int decompress_thread_count =
> +            s->parameters[MIGRATION_PARAMETER_DECOMPRESS_THREADS];
>  
>      memcpy(enabled_capabilities, s->enabled_capabilities,
>             sizeof(enabled_capabilities));
> @@ -413,9 +483,11 @@ static MigrationState *migrate_init(const MigrationParams *params)
>             sizeof(enabled_capabilities));
>      s->xbzrle_cache_size = xbzrle_cache_size;
>  
> -    s->compress_level = compress_level;
> -    s->compress_thread_count = compress_thread_count;
> -    s->decompress_thread_count = decompress_thread_count;
> +    s->parameters[MIGRATION_PARAMETER_COMPRESS_LEVEL] = compress_level;
> +    s->parameters[MIGRATION_PARAMETER_COMPRESS_THREADS] =
> +               compress_thread_count;
> +    s->parameters[MIGRATION_PARAMETER_DECOMPRESS_THREADS] =
> +               decompress_thread_count;
>      s->bandwidth_limit = bandwidth_limit;
>      s->state = MIG_STATE_SETUP;
>      trace_migrate_set_state(MIG_STATE_SETUP);
> @@ -603,7 +675,7 @@ int migrate_compress_level(void)
>  
>      s = migrate_get_current();
>  
> -    return s->compress_level;
> +    return s->parameters[MIGRATION_PARAMETER_COMPRESS_LEVEL];
>  }
>  
>  int migrate_compress_threads(void)
> @@ -612,7 +684,7 @@ int migrate_compress_threads(void)
>  
>      s = migrate_get_current();
>  
> -    return s->compress_thread_count;
> +    return s->parameters[MIGRATION_PARAMETER_COMPRESS_THREADS];
>  }
>  
>  int migrate_decompress_threads(void)
> @@ -621,7 +693,7 @@ int migrate_decompress_threads(void)
>  
>      s = migrate_get_current();
>  
> -    return s->decompress_thread_count;
> +    return s->parameters[MIGRATION_PARAMETER_DECOMPRESS_THREADS];
>  }
>  
>  int migrate_use_xbzrle(void)
> diff --git a/monitor.c b/monitor.c
> index c3cc060..499ae1c 100644
> --- a/monitor.c
> +++ b/monitor.c
> @@ -2873,6 +2873,13 @@ static mon_cmd_t info_cmds[] = {
>          .mhandler.cmd = hmp_info_migrate_capabilities,
>      },
>      {
> +        .name       = "migrate_parameters",
> +        .args_type  = "",
> +        .params     = "",
> +        .help       = "show current migration parameters",
> +        .mhandler.cmd = hmp_info_migrate_parameters,
> +    },
> +    {
>          .name       = "migrate_cache_size",
>          .args_type  = "",
>          .params     = "",
> @@ -4555,6 +4562,24 @@ void migrate_set_capability_completion(ReadLineState *rs, int nb_args,
>      }
>  }
>  
> +void migrate_set_parameter_completion(ReadLineState *rs, int nb_args,
> +                                      const char *str)
> +{
> +    size_t len;
> +
> +    len = strlen(str);
> +    readline_set_completion_index(rs, len);
> +    if (nb_args == 2) {
> +        int i;
> +        for (i = 0; i < MIGRATION_PARAMETER_MAX; i++) {
> +            const char *name = MigrationParameter_lookup[i];
> +            if (!strncmp(str, name, len)) {
> +                readline_add_completion(rs, name);
> +            }
> +        }
> +    }
> +}
> +
>  void host_net_add_completion(ReadLineState *rs, int nb_args, const char *str)
>  {
>      int i;
> diff --git a/qapi-schema.json b/qapi-schema.json
> index 0dfc4ce..5bf21fe 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -541,6 +541,92 @@
>  ##
>  { 'command': 'query-migrate-capabilities', 'returns':   ['MigrationCapabilityStatus']}
>  
> +# @MigrationParameter
> +#
> +# Migration parameters enumeration
> +#
> +# @compress-level: Set the compression level to be used in live migration,
> +#          the compression level is an integer between 0 and 9, where 0 means
> +#          no compression, 1 means the best compression speed, and 9 means best
> +#          compression ratio which will consume more CPU.
> +#
> +# @compress-threads: Set compression thread count to be used in live migration,
> +#          the compression thread count is an integer between 1 and 255.
> +#
> +# @decompress-threads: Set decompression thread count to be used in live
> +#          migration, the decompression thread count is an integer between 1
> +#          and 255. Usually, decompression is at least 4 times as fast as
> +#          compression, so set the decompress-threads to the number about 1/4
> +#          of compress-threads is adequate.
> +#
> +# Since: 2.3
> +##
> +{ 'enum': 'MigrationParameter',
> +  'data': ['compress-level', 'compress-threads', 'decompress-threads'] }
> +##
> +# @MigrationParameterBase
> +#
> +# Migration parameter information
> +#
> +# @parameter: the parameter of migration
> +#
> +# Since: 2.3
> +##
> +{ 'type': 'MigrationParameterBase',
> +  'data': {'parameter': 'MigrationParameter'} }
> +##
> +# @MigrationParameterInt
> +#
> +# Migration parameter information
> +#
> +# @value: parameter int
> +#
> +# Since: 2.3
> +##
> +{ 'type': 'MigrationParameterInt',
> +  'data': {'value': 'int'} }
> +##
> +# @MigrationParameterStatus
> +#
> +# Migration parameter information
> +#
> +# @compress-level: compression level
> +#
> +# @compress-threads: compression thread count
> +#
> +# @decompress-threads: decompression thread count
> +#
> +# Since: 2.3
> +##
> +{ 'union': 'MigrationParameterStatus',
> +  'base': 'MigrationParameterBase',
> +  'discriminator': 'parameter',
> +  'data': { 'compress-level': 'MigrationParameterInt',
> +            'compress-threads': 'MigrationParameterInt',
> +            'decompress-threads': 'MigrationParameterInt'} }
> +#
> +# @migrate-set-parameters
> +#
> +# Set the following migration parameters (like compress-level)
> +#
> +# @parameters: json array of parameter modifications to make
> +#
> +# Since: 2.3
> +##
> +{ 'command': 'migrate-set-parameters',
> +  'data': { 'parameters': ['MigrationParameterStatus'] } }
> +##
> +# @query-migrate-parameters
> +#
> +# Returns information about the current migration parameters status
> +#
> +# Returns: @MigrationParametersStatus
> +#
> +# Since: 2.3
> +##
> +{ 'command': 'query-migrate-parameters',
> +  'returns': ['MigrationParameterStatus'] }
> +##
>  ##
>  # @MouseInfo:
>  #
> diff --git a/qmp-commands.hx b/qmp-commands.hx
> index a85d847..2c4737b 100644
> --- a/qmp-commands.hx
> +++ b/qmp-commands.hx
> @@ -3295,6 +3295,72 @@ EQMP
>      },
>  
>  SQMP
> +migrate-set-parameters
> +----------------------
> +
> +Set migration parameters
> +
> +- "compress-level": set compression level during migration
> +- "compress-threads": set compression thread count for migration
> +- "decompress-threads": set decompression thread count for migration
> +
> +Arguments:
> +
> +Example:
> +
> +-> { "execute": "migrate-set-parameters" , "arguments":
> +     { "parameters": [ { "parameter": "compress-level", "value": 1 } ] } }
> +
> +EQMP
> +
> +    {
> +        .name       = "migrate-set-parameters",
> +        .args_type  = "parameters:O",
> +        .params     = "parameter:s,value:O",
> +	.mhandler.cmd_new = qmp_marshal_input_migrate_set_parameters,
> +    },
> +SQMP
> +query-migrate-parameters
> +------------------------
> +
> +Query current migration parameters
> +
> +- "parameters": migration parameters value
> +         - "compress-level" : compression level value (json-int)
> +         - "compress-threads" : compression thread count value (json-int)
> +         - "decompress-threads" : decompression thread count value (json-int)
> +
> +Arguments:
> +
> +Example:
> +
> +-> { "execute": "query-migrate-parameters" }
> +<- {
> +      "return": [
> +         {
> +            "parameter": "compress-level",
> +            "value": 1
> +         },
> +         {
> +            "parameter": "compress-threads",
> +            "value": 8
> +         },
> +         {
> +            "parameter": "decompress-threads",
> +            "value": 2
> +         }
> +      ]
> +   }
> +
> +EQMP
> +
> +    {
> +        .name       = "query-migrate-parameters",
> +        .args_type  = "",
> +        .mhandler.cmd_new = qmp_marshal_input_query_migrate_parameters,
> +    },
> +
> +SQMP
>  query-balloon
>  -------------
>  
> -- 
> 1.9.1
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK