Add migrate_set_cache_size command

Change XBZRLE cache size in bytes (the size should be a power of 2, it will be
rounded down to the nearest power of 2).
If XBZRLE cache size is too small there will be many cache miss.

New query-migrate-cache-size QMP command and 'info migrate_cache_size' HMP
command to query cache value.

Signed-off-by: Benoit Hudzia <benoit.hudzia@sap.com>
Signed-off-by: Petter Svard <petters@cs.umu.se>
Signed-off-by: Aidan Shribman <aidan.shribman@sap.com>
Signed-off-by: Orit Wasserman <owasserm@redhat.com>

Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/hmp.c b/hmp.c
index 2a03b446a1..8abb4bddb3 100644
--- a/hmp.c
+++ b/hmp.c
@@ -194,6 +194,12 @@ void hmp_info_migrate_capabilities(Monitor *mon)
     qapi_free_MigrationCapabilityStatusList(caps);
 }
 
+void hmp_info_migrate_cache_size(Monitor *mon)
+{
+    monitor_printf(mon, "xbzrel cache size: %" PRId64 " kbytes\n",
+                   qmp_query_migrate_cache_size(NULL) >> 10);
+}
+
 void hmp_info_cpus(Monitor *mon)
 {
     CpuInfoList *cpu_list, *cpu;
@@ -764,6 +770,19 @@ void hmp_migrate_set_downtime(Monitor *mon, const QDict *qdict)
     qmp_migrate_set_downtime(value, NULL);
 }
 
+void hmp_migrate_set_cache_size(Monitor *mon, const QDict *qdict)
+{
+    int64_t value = qdict_get_int(qdict, "value");
+    Error *err = NULL;
+
+    qmp_migrate_set_cache_size(value, &err);
+    if (err) {
+        monitor_printf(mon, "%s\n", error_get_pretty(err));
+        error_free(err);
+        return;
+    }
+}
+
 void hmp_migrate_set_speed(Monitor *mon, const QDict *qdict)
 {
     int64_t value = qdict_get_int(qdict, "value");