[Qemu-devel] [PATCH v3 29/35] postcopy/outgoing: add movebg mode(-m) to migration command

[Isaku Yamahata]

When movebg mode is enabled, the point to send background page is set
to the next page to on-demand page.

Signed-off-by: Isaku Yamahata <address@hidden>
---
 hmp-commands.hx      |    8 +++++---
 hmp.c                |    3 ++-
 migration-postcopy.c |    8 ++++++++
 migration.c          |    5 ++++-
 migration.h          |    1 +
 qapi-schema.json     |    2 +-
 qmp-commands.hx      |    2 +-
 savevm.c             |    1 +
 8 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/hmp-commands.hx b/hmp-commands.hx
index 5e2c77c..942f620 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -826,15 +826,16 @@ ETEXI
 
     {
         .name       = "migrate",
-        .args_type  = "detach:-d,blk:-b,inc:-i,postcopy:-p,nobg:-n,uri:s,"
+        .args_type  = 
"detach:-d,blk:-b,inc:-i,postcopy:-p,movebg:-m,nobg:-n,uri:s,"
                      "forward:i?,backward:i?",
-        .params     = "[-d] [-b] [-i] [-p [-n] uri [forward] [backword]",
+        .params     = "[-d] [-b] [-i] [-p [-n] [-m]] uri [forward] [backword]",
         .help       = "migrate to URI (using -d to not wait for completion)"
                      "\n\t\t\t -b for migration without shared storage with"
                      " full copy of disk\n\t\t\t -i for migration without "
                      "shared storage with incremental copy of disk "
                      "(base image shared between src and destination)"
                      "\n\t\t\t-p for migration with postcopy mode enabled"
+                     "\n\t\t\t-m for move background transfer of postcopy mode"
                      "\n\t\t\t-n for no background transfer of postcopy mode"
                      "\n\t\t\tforward: the number of pages to "
                      "forward-prefault when postcopy (default 0)"
@@ -845,12 +846,13 @@ ETEXI
 
 
 STEXI
address@hidden migrate [-d] [-b] [-i] [-p [-n]] @var{uri} @var{forward} 
@var{backward}
address@hidden migrate [-d] [-b] [-i] [-p [-n] [-m]] @var{uri} @var{forward} 
@var{backward}
 @findex migrate
 Migrate to @var{uri} (using -d to not wait for completion).
        -b for migration with full copy of disk
        -i for migration with incremental copy of disk (base image is shared)
        -p for migration with postcopy mode enabled (forward/backward is 
prefault size when postcopy)
+       -m for migratoin with postcopy mode enabled with moving position
        -n for migration with postcopy mode enabled without background transfer
 ETEXI
 
diff --git a/hmp.c b/hmp.c
index fb1275d..a0bd869 100644
--- a/hmp.c
+++ b/hmp.c
@@ -1036,6 +1036,7 @@ void hmp_migrate(Monitor *mon, const QDict *qdict)
     int blk = qdict_get_try_bool(qdict, "blk", 0);
     int inc = qdict_get_try_bool(qdict, "inc", 0);
     int postcopy = qdict_get_try_bool(qdict, "postcopy", 0);
+    int movebg = qdict_get_try_bool(qdict, "movebg", 0);
     int nobg = qdict_get_try_bool(qdict, "nobg", 0);
     int forward = qdict_get_try_int(qdict, "forward", 0);
     int backward = qdict_get_try_int(qdict, "backward", 0);
@@ -1043,7 +1044,7 @@ void hmp_migrate(Monitor *mon, const QDict *qdict)
     Error *err = NULL;
 
     qmp_migrate(uri, !!blk, blk, !!inc, inc, false, false,
-                !!postcopy, postcopy, !!nobg, nobg,
+                !!postcopy, postcopy, !!movebg, movebg, !!nobg, nobg,
                 !!forward, forward, !!backward, backward,
                 &err);
     if (err) {
diff --git a/migration-postcopy.c b/migration-postcopy.c
index 3d51898..421fb39 100644
--- a/migration-postcopy.c
+++ b/migration-postcopy.c
@@ -432,6 +432,14 @@ static int 
postcopy_outgoing_handle_req(PostcopyOutgoingState *s,
                                                 true, j);
             }
         }
+        if (s->ms->params.movebg) {
+            ram_addr_t last_offset =
+                (req->pgoffs[req->nr - 1] + s->ms->params.prefault_forward) <<
+                TARGET_PAGE_BITS;
+            last_offset = MIN(last_offset,
+                              s->last_block_read->length - TARGET_PAGE_SIZE);
+            ram_save_set_last_block(s->last_block_read, last_offset);
+        }
         /* backward prefault */
         for (j = 1; j <= s->ms->params.prefault_backward; j++) {
             for (i = 0; i < req->nr; i++) {
diff --git a/migration.c b/migration.c
index f29e3bb..057ea31 100644
--- a/migration.c
+++ b/migration.c
@@ -510,7 +510,9 @@ void migrate_del_blocker(Error *reason)
 
 void qmp_migrate(const char *uri, bool has_blk, bool blk,
                  bool has_inc, bool inc, bool has_detach, bool detach,
-                 bool has_postcopy, bool postcopy, bool has_nobg, bool nobg,
+                 bool has_postcopy, bool postcopy,
+                 bool has_movebg, bool movebg,
+                 bool has_nobg, bool nobg,
                  bool has_forward, int64_t forward,
                  bool has_backward, int64_t backward,
                  Error **errp)
@@ -524,6 +526,7 @@ void qmp_migrate(const char *uri, bool has_blk, bool blk,
     params.shared = inc;
     params.postcopy = postcopy;
     params.nobg = nobg;
+    params.movebg = movebg;
     params.prefault_forward = 0;
     if (has_forward) {
         if (forward < 0) {
diff --git a/migration.h b/migration.h
index 8462251..6cc3682 100644
--- a/migration.h
+++ b/migration.h
@@ -26,6 +26,7 @@ struct MigrationParams {
     bool shared;
     bool postcopy;
     bool nobg;
+    bool movebg;
     int64_t prefault_forward;
     int64_t prefault_backward;
 };
diff --git a/qapi-schema.json b/qapi-schema.json
index 746bf21..cf5d988 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -2095,7 +2095,7 @@
 ##
 { 'command': 'migrate',
   'data': {'uri': 'str', '*blk': 'bool', '*inc': 'bool', '*detach': 'bool' ,
-           '*postcopy': 'bool', '*nobg': 'bool',
+           '*postcopy': 'bool', '*movebg': 'bool', '*nobg': 'bool',
            '*forward': 'int', '*backward': 'int'} }
 
 # @xen-save-devices-state:
diff --git a/qmp-commands.hx b/qmp-commands.hx
index defbeba..7028ece 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -518,7 +518,7 @@ EQMP
 
     {
         .name       = "migrate",
-        .args_type  = "detach:-d,blk:-b,inc:-i,postcopy:-p,nobg:-n,uri:s",
+        .args_type  = 
"detach:-d,blk:-b,inc:-i,postcopy:-p,movebg:-m,nobg:-n,uri:s",
         .mhandler.cmd_new = qmp_marshal_input_migrate,
     },
 
diff --git a/savevm.c b/savevm.c
index 0a3acd8..8d26354 100644
--- a/savevm.c
+++ b/savevm.c
@@ -1839,6 +1839,7 @@ static int qemu_savevm_state(QEMUFile *f)
         .blk = 0,
         .shared = 0,
         .postcopy = 0,
+        .movebg = 0,
         .nobg = 0,
     };
 
-- 
1.7.10.4