[Qemu-devel] [PATCH v7 23/42] MIGRATION_STATUS_POSTCOPY_ACTIVE: Add new migration state

["Dr. David Alan Gilbert (git)" <dgilbert@redhat.com>]

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

'MIGRATION_STATUS_POSTCOPY_ACTIVE' is entered after migrate_start_postcopy

'migration_postcopy_phase' is provided for other sections to know if
they're in postcopy.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
 include/migration/migration.h |  2 ++
 migration/migration.c         | 56 ++++++++++++++++++++++++++++++++++++-------
 qapi-schema.json              |  4 +++-
 trace-events                  |  1 +
 4 files changed, 54 insertions(+), 9 deletions(-)

diff --git a/include/migration/migration.h b/include/migration/migration.h
index e973490..2a22381 100644
--- a/include/migration/migration.h
+++ b/include/migration/migration.h
@@ -154,6 +154,8 @@ MigrationState *migrate_init(const MigrationParams *params);
 bool migration_in_setup(MigrationState *);
 bool migration_has_finished(MigrationState *);
 bool migration_has_failed(MigrationState *);
+/* True if outgoing migration has entered postcopy phase */
+bool migration_postcopy_phase(MigrationState *);
 MigrationState *migrate_get_current(void);
 
 void migrate_compress_threads_create(void);
diff --git a/migration/migration.c b/migration/migration.c
index 6fc47f9..22be23e 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -288,6 +288,7 @@ static bool migration_already_active(MigrationState *ms)
 {
     switch (ms->state) {
     case MIGRATION_STATUS_ACTIVE:
+    case MIGRATION_STATUS_POSTCOPY_ACTIVE:
     case MIGRATION_STATUS_SETUP:
         return true;
 
@@ -358,6 +359,39 @@ MigrationInfo *qmp_query_migrate(Error **errp)
 
         get_xbzrle_cache_stats(info);
         break;
+    case MIGRATION_STATUS_POSTCOPY_ACTIVE:
+        /* Mostly the same as active; TODO add some postcopy stats */
+        info->has_status = true;
+        info->has_total_time = true;
+        info->total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME)
+            - s->total_time;
+        info->has_expected_downtime = true;
+        info->expected_downtime = s->expected_downtime;
+        info->has_setup_time = true;
+        info->setup_time = s->setup_time;
+
+        info->has_ram = true;
+        info->ram = g_malloc0(sizeof(*info->ram));
+        info->ram->transferred = ram_bytes_transferred();
+        info->ram->remaining = ram_bytes_remaining();
+        info->ram->total = ram_bytes_total();
+        info->ram->duplicate = dup_mig_pages_transferred();
+        info->ram->skipped = skipped_mig_pages_transferred();
+        info->ram->normal = norm_mig_pages_transferred();
+        info->ram->normal_bytes = norm_mig_bytes_transferred();
+        info->ram->dirty_pages_rate = s->dirty_pages_rate;
+        info->ram->mbps = s->mbps;
+
+        if (blk_mig_active()) {
+            info->has_disk = true;
+            info->disk = g_malloc0(sizeof(*info->disk));
+            info->disk->transferred = blk_mig_bytes_transferred();
+            info->disk->remaining = blk_mig_bytes_remaining();
+            info->disk->total = blk_mig_bytes_total();
+        }
+
+        get_xbzrle_cache_stats(info);
+        break;
     case MIGRATION_STATUS_COMPLETED:
         get_xbzrle_cache_stats(info);
 
@@ -399,8 +433,7 @@ void qmp_migrate_set_capabilities(MigrationCapabilityStatusList *params,
     MigrationState *s = migrate_get_current();
     MigrationCapabilityStatusList *cap;
 
-    if (s->state == MIGRATION_STATUS_ACTIVE ||
-        s->state == MIGRATION_STATUS_SETUP) {
+    if (migration_already_active(s)) {
         error_set(errp, QERR_MIGRATION_ACTIVE);
         return;
     }
@@ -531,7 +564,8 @@ static void migrate_fd_cleanup(void *opaque)
         s->file = NULL;
     }
 
-    assert(s->state != MIGRATION_STATUS_ACTIVE);
+    assert((s->state != MIGRATION_STATUS_ACTIVE) &&
+           (s->state != MIGRATION_STATUS_POSTCOPY_ACTIVE));
 
     if (s->state != MIGRATION_STATUS_COMPLETED) {
         qemu_savevm_state_cancel();
@@ -566,8 +600,7 @@ static void migrate_fd_cancel(MigrationState *s)
 
     do {
         old_state = s->state;
-        if (old_state != MIGRATION_STATUS_SETUP &&
-            old_state != MIGRATION_STATUS_ACTIVE) {
+        if (!migration_already_active(s)) {
             break;
         }
         migrate_set_state(s, old_state, MIGRATION_STATUS_CANCELLING);
@@ -611,6 +644,11 @@ bool migration_has_failed(MigrationState *s)
             s->state == MIGRATION_STATUS_FAILED);
 }
 
+bool migration_postcopy_phase(MigrationState *s)
+{
+    return (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE);
+}
+
 MigrationState *migrate_init(const MigrationParams *params)
 {
     MigrationState *s = migrate_get_current();
@@ -692,8 +730,7 @@ void qmp_migrate(const char *uri, bool has_blk, bool blk,
     params.blk = has_blk && blk;
     params.shared = has_inc && inc;
 
-    if (s->state == MIGRATION_STATUS_ACTIVE ||
-        s->state == MIGRATION_STATUS_SETUP ||
+    if (migration_already_active(s) ||
         s->state == MIGRATION_STATUS_CANCELLING) {
         error_set(errp, QERR_MIGRATION_ACTIVE);
         return;
@@ -1041,7 +1078,10 @@ static void *migration_thread(void *opaque)
     s->setup_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) - setup_start;
     migrate_set_state(s, MIGRATION_STATUS_SETUP, MIGRATION_STATUS_ACTIVE);
 
-    while (s->state == MIGRATION_STATUS_ACTIVE) {
+    trace_migration_thread_setup_complete();
+
+    while (s->state == MIGRATION_STATUS_ACTIVE ||
+           s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) {
         int64_t current_time;
         uint64_t pending_size;
 
diff --git a/qapi-schema.json b/qapi-schema.json
index b0177bb..5e2f487 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -424,6 +424,8 @@
 #
 # @active: in the process of doing migration.
 #
+# @postcopy-active: like active, but now in postcopy mode. (since 2.4)
+#
 # @completed: migration is finished.
 #
 # @failed: some error occurred during migration process.
@@ -433,7 +435,7 @@
 ##
 { 'enum': 'MigrationStatus',
   'data': [ 'none', 'setup', 'cancelling', 'cancelled',
-            'active', 'completed', 'failed' ] }
+            'active', 'postcopy-active', 'completed', 'failed' ] }
 
 ##
 # @MigrationInfo
diff --git a/trace-events b/trace-events
index 339eb71..72e9889 100644
--- a/trace-events
+++ b/trace-events
@@ -1421,6 +1421,7 @@ migrate_fd_error(void) ""
 migrate_fd_cancel(void) ""
 migrate_pending(uint64_t size, uint64_t max, uint64_t post, uint64_t nonpost) "pending size %" PRIu64 " max %" PRIu64 " (post=%" PRIu64 " nonpost=%" PRIu64 ")"
 migrate_send_rp_message(int msg_type, uint16_t len) "%d: len %d"
+migration_thread_setup_complete(void) ""
 open_return_path_on_source(void) ""
 open_return_path_on_source_continue(void) ""
 source_return_path_thread_bad_end(void) ""
-- 
2.4.3