From d6500340dc3c1152b5efe04ef3daa50c17a55e30 Mon Sep 17 00:00:00 2001 From: Leonardo Bras Date: Fri, 13 May 2022 03:28:33 -0300 Subject: [PATCH 10/18] migration: Add zero-copy-send parameter for QMP/HMP for Linux MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RH-Author: Leonardo Brás RH-MergeRequest: 95: MSG_ZEROCOPY + Multifd RH-Commit: [4/11] 514d98d595992c53ff98de750035e080ded8972e (LeoBras/centos-qemu-kvm) RH-Bugzilla: 1968509 RH-Acked-by: Miroslav Rezanina RH-Acked-by: Dr. David Alan Gilbert RH-Acked-by: Peter Xu Add property that allows zero-copy migration of memory pages on the sending side, and also includes a helper function migrate_use_zero_copy_send() to check if it's enabled. No code is introduced to actually do the migration, but it allow future implementations to enable/disable this feature. On non-Linux builds this parameter is compiled-out. Signed-off-by: Leonardo Bras Reviewed-by: Peter Xu Reviewed-by: Daniel P. Berrangé Reviewed-by: Juan Quintela Acked-by: Markus Armbruster Message-Id: <20220513062836.965425-5-leobras@redhat.com> Signed-off-by: Dr. David Alan Gilbert (cherry picked from commit abb6295b3ace5d17c3a65936913fc346616dbf14) Signed-off-by: Leonardo Bras --- migration/migration.c | 32 ++++++++++++++++++++++++++++++++ migration/migration.h | 5 +++++ migration/socket.c | 11 +++++++++-- monitor/hmp-cmds.c | 6 ++++++ qapi/migration.json | 24 ++++++++++++++++++++++++ 5 files changed, 76 insertions(+), 2 deletions(-) diff --git a/migration/migration.c b/migration/migration.c index 695f0f2900..0a6b3b9f4d 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -899,6 +899,10 @@ MigrationParameters *qmp_query_migrate_parameters(Error **errp) params->multifd_zlib_level = s->parameters.multifd_zlib_level; params->has_multifd_zstd_level = true; params->multifd_zstd_level = s->parameters.multifd_zstd_level; +#ifdef CONFIG_LINUX + params->has_zero_copy_send = true; + params->zero_copy_send = s->parameters.zero_copy_send; +#endif params->has_xbzrle_cache_size = true; params->xbzrle_cache_size = s->parameters.xbzrle_cache_size; params->has_max_postcopy_bandwidth = true; @@ -1555,6 +1559,11 @@ static void migrate_params_test_apply(MigrateSetParameters *params, if (params->has_multifd_compression) { dest->multifd_compression = params->multifd_compression; } +#ifdef CONFIG_LINUX + if (params->has_zero_copy_send) { + dest->zero_copy_send = params->zero_copy_send; + } +#endif if (params->has_xbzrle_cache_size) { dest->xbzrle_cache_size = params->xbzrle_cache_size; } @@ -1667,6 +1676,11 @@ static void migrate_params_apply(MigrateSetParameters *params, Error **errp) if (params->has_multifd_compression) { s->parameters.multifd_compression = params->multifd_compression; } +#ifdef CONFIG_LINUX + if (params->has_zero_copy_send) { + s->parameters.zero_copy_send = params->zero_copy_send; + } +#endif if (params->has_xbzrle_cache_size) { s->parameters.xbzrle_cache_size = params->xbzrle_cache_size; xbzrle_cache_resize(params->xbzrle_cache_size, errp); @@ -2557,6 +2571,17 @@ int migrate_multifd_zstd_level(void) return s->parameters.multifd_zstd_level; } +#ifdef CONFIG_LINUX +bool migrate_use_zero_copy_send(void) +{ + MigrationState *s; + + s = migrate_get_current(); + + return s->parameters.zero_copy_send; +} +#endif + int migrate_use_xbzrle(void) { MigrationState *s; @@ -4200,6 +4225,10 @@ static Property migration_properties[] = { DEFINE_PROP_UINT8("multifd-zstd-level", MigrationState, parameters.multifd_zstd_level, DEFAULT_MIGRATE_MULTIFD_ZSTD_LEVEL), +#ifdef CONFIG_LINUX + DEFINE_PROP_BOOL("zero_copy_send", MigrationState, + parameters.zero_copy_send, false), +#endif DEFINE_PROP_SIZE("xbzrle-cache-size", MigrationState, parameters.xbzrle_cache_size, DEFAULT_MIGRATE_XBZRLE_CACHE_SIZE), @@ -4297,6 +4326,9 @@ static void migration_instance_init(Object *obj) params->has_multifd_compression = true; params->has_multifd_zlib_level = true; params->has_multifd_zstd_level = true; +#ifdef CONFIG_LINUX + params->has_zero_copy_send = true; +#endif params->has_xbzrle_cache_size = true; params->has_max_postcopy_bandwidth = true; params->has_max_cpu_throttle = true; diff --git a/migration/migration.h b/migration/migration.h index 2de861df01..5bcb7628ef 100644 --- a/migration/migration.h +++ b/migration/migration.h @@ -376,6 +376,11 @@ MultiFDCompression migrate_multifd_compression(void); int migrate_multifd_zlib_level(void); int migrate_multifd_zstd_level(void); +#ifdef CONFIG_LINUX +bool migrate_use_zero_copy_send(void); +#else +#define migrate_use_zero_copy_send() (false) +#endif int migrate_use_xbzrle(void); uint64_t migrate_xbzrle_cache_size(void); bool migrate_colo_enabled(void); diff --git a/migration/socket.c b/migration/socket.c index 05705a32d8..3754d8f72c 100644 --- a/migration/socket.c +++ b/migration/socket.c @@ -74,9 +74,16 @@ static void socket_outgoing_migration(QIOTask *task, if (qio_task_propagate_error(task, &err)) { trace_migration_socket_outgoing_error(error_get_pretty(err)); - } else { - trace_migration_socket_outgoing_connected(data->hostname); + goto out; } + + trace_migration_socket_outgoing_connected(data->hostname); + + if (migrate_use_zero_copy_send()) { + error_setg(&err, "Zero copy send not available in migration"); + } + +out: migration_channel_connect(data->s, sioc, data->hostname, err); object_unref(OBJECT(sioc)); } diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c index 634968498b..55b48d3733 100644 --- a/monitor/hmp-cmds.c +++ b/monitor/hmp-cmds.c @@ -1309,6 +1309,12 @@ void hmp_migrate_set_parameter(Monitor *mon, const QDict *qdict) p->has_multifd_zstd_level = true; visit_type_uint8(v, param, &p->multifd_zstd_level, &err); break; +#ifdef CONFIG_LINUX + case MIGRATION_PARAMETER_ZERO_COPY_SEND: + p->has_zero_copy_send = true; + visit_type_bool(v, param, &p->zero_copy_send, &err); + break; +#endif case MIGRATION_PARAMETER_XBZRLE_CACHE_SIZE: p->has_xbzrle_cache_size = true; if (!visit_type_size(v, param, &cache_size, &err)) { diff --git a/qapi/migration.json b/qapi/migration.json index 27d7b28158..4d833ecdd6 100644 --- a/qapi/migration.json +++ b/qapi/migration.json @@ -741,6 +741,13 @@ # will consume more CPU. # Defaults to 1. (Since 5.0) # +# @zero-copy-send: Controls behavior on sending memory pages on migration. +# When true, enables a zero-copy mechanism for sending +# memory pages, if host supports it. +# Requires that QEMU be permitted to use locked memory +# for guest RAM pages. +# Defaults to false. (Since 7.1) +# # @block-bitmap-mapping: Maps block nodes and bitmaps on them to # aliases for the purpose of dirty bitmap migration. Such # aliases may for example be the corresponding names on the @@ -780,6 +787,7 @@ 'xbzrle-cache-size', 'max-postcopy-bandwidth', 'max-cpu-throttle', 'multifd-compression', 'multifd-zlib-level' ,'multifd-zstd-level', + { 'name': 'zero-copy-send', 'if' : 'CONFIG_LINUX'}, 'block-bitmap-mapping' ] } ## @@ -906,6 +914,13 @@ # will consume more CPU. # Defaults to 1. (Since 5.0) # +# @zero-copy-send: Controls behavior on sending memory pages on migration. +# When true, enables a zero-copy mechanism for sending +# memory pages, if host supports it. +# Requires that QEMU be permitted to use locked memory +# for guest RAM pages. +# Defaults to false. (Since 7.1) +# # @block-bitmap-mapping: Maps block nodes and bitmaps on them to # aliases for the purpose of dirty bitmap migration. Such # aliases may for example be the corresponding names on the @@ -960,6 +975,7 @@ '*multifd-compression': 'MultiFDCompression', '*multifd-zlib-level': 'uint8', '*multifd-zstd-level': 'uint8', + '*zero-copy-send': { 'type': 'bool', 'if': 'CONFIG_LINUX' }, '*block-bitmap-mapping': [ 'BitmapMigrationNodeAlias' ] } } ## @@ -1106,6 +1122,13 @@ # will consume more CPU. # Defaults to 1. (Since 5.0) # +# @zero-copy-send: Controls behavior on sending memory pages on migration. +# When true, enables a zero-copy mechanism for sending +# memory pages, if host supports it. +# Requires that QEMU be permitted to use locked memory +# for guest RAM pages. +# Defaults to false. (Since 7.1) +# # @block-bitmap-mapping: Maps block nodes and bitmaps on them to # aliases for the purpose of dirty bitmap migration. Such # aliases may for example be the corresponding names on the @@ -1158,6 +1181,7 @@ '*multifd-compression': 'MultiFDCompression', '*multifd-zlib-level': 'uint8', '*multifd-zstd-level': 'uint8', + '*zero-copy-send': { 'type': 'bool', 'if': 'CONFIG_LINUX' }, '*block-bitmap-mapping': [ 'BitmapMigrationNodeAlias' ] } } ## -- 2.35.3