From 4886a1bcb7d7a88da02eefb0f33327c613ac52a3 Mon Sep 17 00:00:00 2001 From: "Dr. David Alan Gilbert" Date: Thu, 5 Nov 2015 18:10:56 +0000 Subject: [PATCH] migrate_start_postcopy: Command to trigger transition to postcopy Once postcopy is enabled (with migrate_set_capability), the migration will still start on precopy mode. To cause a transition into postcopy the: migrate_start_postcopy command must be issued. Postcopy will start sometime after this (when it's next checked in the migration loop). Issuing the command before migration has started will error, and issuing after it has finished is ignored. Signed-off-by: Dr. David Alan Gilbert Reviewed-by: Eric Blake Reviewed-by: Juan Quintela Reviewed-by: Amit Shah Signed-off-by: Juan Quintela --- hmp-commands.hx | 15 +++++++++++++++ hmp.c | 7 +++++++ hmp.h | 1 + include/migration/migration.h | 3 +++ migration/migration.c | 22 ++++++++++++++++++++++ qapi-schema.json | 8 ++++++++ qmp-commands.hx | 19 +++++++++++++++++++ 7 files changed, 75 insertions(+) diff --git a/hmp-commands.hx b/hmp-commands.hx index 3a4ae3950a..8939b9838a 100644 --- a/hmp-commands.hx +++ b/hmp-commands.hx @@ -1005,6 +1005,21 @@ STEXI @item migrate_set_parameter @var{parameter} @var{value} @findex migrate_set_parameter Set the parameter @var{parameter} for migration. +ETEXI + + { + .name = "migrate_start_postcopy", + .args_type = "", + .params = "", + .help = "Switch migration to postcopy mode", + .mhandler.cmd = hmp_migrate_start_postcopy, + }, + +STEXI +@item migrate_start_postcopy +@findex migrate_start_postcopy +Switch in-progress migration to postcopy mode. Ignored after the end of +migration (or once already in postcopy). ETEXI { diff --git a/hmp.c b/hmp.c index a15d00c18c..e1f854aefe 100644 --- a/hmp.c +++ b/hmp.c @@ -1293,6 +1293,13 @@ void hmp_client_migrate_info(Monitor *mon, const QDict *qdict) hmp_handle_error(mon, &err); } +void hmp_migrate_start_postcopy(Monitor *mon, const QDict *qdict) +{ + Error *err = NULL; + qmp_migrate_start_postcopy(&err); + hmp_handle_error(mon, &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 81656c3d82..a8c5b5a9a6 100644 --- a/hmp.h +++ b/hmp.h @@ -69,6 +69,7 @@ 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_client_migrate_info(Monitor *mon, const QDict *qdict); +void hmp_migrate_start_postcopy(Monitor *mon, const QDict *qdict); void hmp_set_password(Monitor *mon, const QDict *qdict); void hmp_expire_password(Monitor *mon, const QDict *qdict); void hmp_eject(Monitor *mon, const QDict *qdict); diff --git a/include/migration/migration.h b/include/migration/migration.h index 2e9fa3c65d..217666650a 100644 --- a/include/migration/migration.h +++ b/include/migration/migration.h @@ -127,6 +127,9 @@ struct MigrationState int64_t xbzrle_cache_size; int64_t setup_time; int64_t dirty_sync_count; + + /* Flag set once the migration has been asked to enter postcopy */ + bool start_postcopy; }; void process_incoming_migration(QEMUFile *f); diff --git a/migration/migration.c b/migration/migration.c index bb4c92ef93..9c46472949 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -668,6 +668,28 @@ void qmp_migrate_set_parameters(bool has_compress_level, } } +void qmp_migrate_start_postcopy(Error **errp) +{ + MigrationState *s = migrate_get_current(); + + if (!migrate_postcopy_ram()) { + error_setg(errp, "Enable postcopy with migration_set_capability before" + " the start of migration"); + return; + } + + if (s->state == MIGRATION_STATUS_NONE) { + error_setg(errp, "Postcopy must be started after migration has been" + " started"); + return; + } + /* + * we don't error if migration has finished since that would be racy + * with issuing this command. + */ + atomic_set(&s->start_postcopy, true); +} + /* shared migration helpers */ static void migrate_set_state(MigrationState *s, int old_state, int new_state) diff --git a/qapi-schema.json b/qapi-schema.json index 8638d428b9..d25df93034 100644 --- a/qapi-schema.json +++ b/qapi-schema.json @@ -701,6 +701,14 @@ 'data': { 'protocol': 'str', 'hostname': 'str', '*port': 'int', '*tls-port': 'int', '*cert-subject': 'str' } } +## +# @migrate-start-postcopy +# +# Switch migration to postcopy mode +# +# Since: 2.5 +{ 'command': 'migrate-start-postcopy' } + ## # @MouseInfo: # diff --git a/qmp-commands.hx b/qmp-commands.hx index d7cf0ff264..7f85d4046c 100644 --- a/qmp-commands.hx +++ b/qmp-commands.hx @@ -717,6 +717,25 @@ Example: <- { "return": {} } EQMP + { + .name = "migrate-start-postcopy", + .args_type = "", + .mhandler.cmd_new = qmp_marshal_migrate_start_postcopy, + }, + +SQMP +migrate-start-postcopy +---------------------- + +Switch an in-progress migration to postcopy mode. Ignored after the end of +migration (or once already in postcopy). + +Example: +-> { "execute": "migrate-start-postcopy" } +<- { "return": {} } + +EQMP + { .name = "query-migrate-cache-size", .args_type = "",