migration: Add zero-copy-send parameter for QMP/HMP for Linux

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 <leobras@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20220513062836.965425-5-leobras@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
This commit is contained in:
Leonardo Bras 2022-05-13 03:28:33 -03:00 committed by Dr. David Alan Gilbert
parent 2bc58ffc29
commit abb6295b3a
5 changed files with 76 additions and 2 deletions

View file

@ -910,6 +910,10 @@ 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;
@ -1567,6 +1571,11 @@ 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;
}
@ -1679,6 +1688,11 @@ 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);
@ -2563,6 +2577,17 @@ 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;
@ -4206,6 +4231,10 @@ 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),
@ -4303,6 +4332,9 @@ 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;

View file

@ -375,6 +375,11 @@ 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);

View file

@ -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));
}