[Qemu-devel] [RFC PATCH RDMA support v1: 10/13] introduce new command migrate_check_for_zero

[mrhines@linux.vnet.ibm.com]

From: "Michael R. Hines" <mrhines@us.ibm.com>

This allows the user to disable zero page checking during migration

Signed-off-by: Michael R. Hines <mrhines@us.ibm.com>
---
 hmp-commands.hx  |   14 ++++++++++++++
 hmp.c            |    6 ++++++
 hmp.h            |    1 +
 migration.c      |   12 ++++++++++++
 qapi-schema.json |   13 +++++++++++++
 qmp-commands.hx  |   23 +++++++++++++++++++++++
 6 files changed, 69 insertions(+)

diff --git a/hmp-commands.hx b/hmp-commands.hx
index 3d98604..b593095 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -962,6 +962,20 @@ Set maximum tolerated downtime (in seconds) for migration.
 ETEXI
 
     {
+        .name       = "migrate_check_for_zero",
+        .args_type  = "value:b",
+        .params     = "value",
+        .help       = "Control whether or not to check for zero pages",
+        .mhandler.cmd = hmp_migrate_check_for_zero,
+    },
+
+STEXI
+@item migrate_check_for_zero @var{value}
+@findex migrate_check_for_zero
+Control whether or not to check for zero pages.
+ETEXI
+
+    {
         .name       = "migrate_set_capability",
         .args_type  = "capability:s,state:b",
         .params     = "capability state",
diff --git a/hmp.c b/hmp.c
index dbe9b90..68ba93a 100644
--- a/hmp.c
+++ b/hmp.c
@@ -909,6 +909,12 @@ void hmp_migrate_set_downtime(Monitor *mon, const QDict *qdict)
     qmp_migrate_set_downtime(value, NULL);
 }
 
+void hmp_migrate_check_for_zero(Monitor *mon, const QDict *qdict)
+{
+    bool value = qdict_get_bool(qdict, "value");
+    qmp_migrate_check_for_zero(value, NULL);
+}
+
 void hmp_migrate_set_cache_size(Monitor *mon, const QDict *qdict)
 {
     int64_t value = qdict_get_int(qdict, "value");
diff --git a/hmp.h b/hmp.h
index 80e8b41..a6595da 100644
--- a/hmp.h
+++ b/hmp.h
@@ -58,6 +58,7 @@ void hmp_snapshot_blkdev(Monitor *mon, const QDict *qdict);
 void hmp_drive_mirror(Monitor *mon, const QDict *qdict);
 void hmp_migrate_cancel(Monitor *mon, const QDict *qdict);
 void hmp_migrate_set_downtime(Monitor *mon, const QDict *qdict);
+void hmp_migrate_check_for_zero(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_cache_size(Monitor *mon, const QDict *qdict);
diff --git a/migration.c b/migration.c
index a2fcacf..9072479 100644
--- a/migration.c
+++ b/migration.c
@@ -485,6 +485,18 @@ void qmp_migrate_set_downtime(double value, Error **errp)
     max_downtime = (uint64_t)value;
 }
 
+static bool check_for_zero = true;
+
+void qmp_migrate_check_for_zero(bool value, Error **errp)
+{
+    check_for_zero = value;
+}
+
+bool migrate_check_for_zero(void)
+{
+    return check_for_zero;
+}
+
 bool migrate_chunk_register_destination(void)
 {
     MigrationState *s;
diff --git a/qapi-schema.json b/qapi-schema.json
index 7fe7e5c..1ca939f 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1792,6 +1792,19 @@
 { 'command': 'migrate_set_downtime', 'data': {'value': 'number'} }
 
 ##
+# @migrate_check_for_zero
+#
+# Control whether or not to check for zero pages during migration.
+#
+# @value: on|off 
+#
+# Returns: nothing on success
+#
+# Since: 1.5.0
+##
+{ 'command': 'migrate_check_for_zero', 'data': {'value': 'bool'} }
+
+##
 # @migrate_set_speed
 #
 # Set maximum speed for migration.
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 1e0e11e..78cda67 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -750,6 +750,29 @@ Example:
 EQMP
 
     {
+        .name       = "migrate_check_for_zero",
+        .args_type  = "value:b",
+        .mhandler.cmd_new = qmp_marshal_input_migrate_check_for_zero,
+    },
+
+SQMP
+migrate_check_for_zero
+----------------------
+
+Control whether or not to check for zero pages.
+
+Arguments:
+
+- "value": true or false (json-bool) 
+
+Example:
+
+-> { "execute": "migrate_check_for_zero", "arguments": { "value": true } }
+<- { "return": {} }
+
+EQMP
+
+    {
         .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",
-- 
1.7.10.4