[Qemu-devel] [RFC PATCH v1: 04/12] mc: introduce a "checkpointing" status check into the VCPU states

[mrhines]

From: "Michael R. Hines" <address@hidden>

During micro-checkpointing, the VCPUs get repeatedly paused and
resumed. We need to not freak out when the VM begins micro-checkpointing.

Signed-off-by: Michael R. Hines <address@hidden>
---
 arch_init.c                   | 2 +-
 cpus.c                        | 9 ++++++++-
 include/migration/migration.h | 2 ++
 qapi-schema.json              | 4 +++-
 vl.c                          | 6 ++++++
 5 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/arch_init.c b/arch_init.c
index 4a71311..b139512 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -199,7 +199,7 @@ typedef struct AccountingInfo {
 
 static AccountingInfo acct_info;
 
-static void acct_clear(void)
+void acct_clear(void)
 {
     memset(&acct_info, 0, sizeof(acct_info));
 }
diff --git a/cpus.c b/cpus.c
index 398229e..d090c2c 100644
--- a/cpus.c
+++ b/cpus.c
@@ -530,7 +530,14 @@ static int do_vm_stop(RunState state)
         pause_all_vcpus();
         runstate_set(state);
         vm_state_notify(0, state);
-        monitor_protocol_event(QEVENT_STOP, NULL);
+        /*
+         * If MC is enabled, libvirt gets confused 
+         * because it thinks the VM is stopped when 
+         * its just being micro-checkpointed.
+         */
+        if(state != RUN_STATE_CHECKPOINT_VM) {
+            monitor_protocol_event(QEVENT_STOP, NULL);
+        }
     }
 
     bdrv_drain_all();
diff --git a/include/migration/migration.h b/include/migration/migration.h
index 3ffc433..3ad06c5 100644
--- a/include/migration/migration.h
+++ b/include/migration/migration.h
@@ -119,6 +119,8 @@ uint64_t xbzrle_mig_bytes_transferred(void);
 uint64_t xbzrle_mig_pages_transferred(void);
 uint64_t xbzrle_mig_pages_overflow(void);
 uint64_t xbzrle_mig_pages_cache_miss(void);
+void acct_clear(void);
+
 void *migration_bitmap_worker(void *opaque);
 void migration_bitmap_worker_start(MigrationState *s);
 void migration_bitmap_worker_stop(MigrationState *s);
diff --git a/qapi-schema.json b/qapi-schema.json
index aac0894..8e72bcf 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -169,6 +169,8 @@
 #
 # @save-vm: guest is paused to save the VM state
 #
+# @checkpoint-vm: guest is paused to checkpoint the VM state
+#
 # @shutdown: guest is shut down (and -no-shutdown is in use)
 #
 # @suspended: guest is suspended (ACPI S3)
@@ -181,7 +183,7 @@
   'data': [ 'debug', 'inmigrate', 'internal-error', 'io-error', 'paused',
             'postmigrate', 'prelaunch', 'finish-migrate', 'restore-vm',
             'running', 'save-vm', 'shutdown', 'suspended', 'watchdog',
-            'guest-panicked' ] }
+            'guest-panicked', 'checkpoint-vm' ] }
 
 ##
 # @SnapshotInfo
diff --git a/vl.c b/vl.c
index e2ba2e8..74d52ab 100644
--- a/vl.c
+++ b/vl.c
@@ -611,14 +611,18 @@ static const RunStateTransition 
runstate_transitions_def[] = {
 
     { RUN_STATE_FINISH_MIGRATE, RUN_STATE_RUNNING },
     { RUN_STATE_FINISH_MIGRATE, RUN_STATE_POSTMIGRATE },
+    { RUN_STATE_FINISH_MIGRATE, RUN_STATE_CHECKPOINT_VM },
 
     { RUN_STATE_RESTORE_VM, RUN_STATE_RUNNING },
 
+    { RUN_STATE_CHECKPOINT_VM, RUN_STATE_RUNNING },
+
     { RUN_STATE_RUNNING, RUN_STATE_DEBUG },
     { RUN_STATE_RUNNING, RUN_STATE_INTERNAL_ERROR },
     { RUN_STATE_RUNNING, RUN_STATE_IO_ERROR },
     { RUN_STATE_RUNNING, RUN_STATE_PAUSED },
     { RUN_STATE_RUNNING, RUN_STATE_FINISH_MIGRATE },
+    { RUN_STATE_RUNNING, RUN_STATE_CHECKPOINT_VM },
     { RUN_STATE_RUNNING, RUN_STATE_RESTORE_VM },
     { RUN_STATE_RUNNING, RUN_STATE_SAVE_VM },
     { RUN_STATE_RUNNING, RUN_STATE_SHUTDOWN },
@@ -634,9 +638,11 @@ static const RunStateTransition runstate_transitions_def[] 
= {
     { RUN_STATE_RUNNING, RUN_STATE_SUSPENDED },
     { RUN_STATE_SUSPENDED, RUN_STATE_RUNNING },
     { RUN_STATE_SUSPENDED, RUN_STATE_FINISH_MIGRATE },
+    { RUN_STATE_SUSPENDED, RUN_STATE_CHECKPOINT_VM },
 
     { RUN_STATE_WATCHDOG, RUN_STATE_RUNNING },
     { RUN_STATE_WATCHDOG, RUN_STATE_FINISH_MIGRATE },
+    { RUN_STATE_WATCHDOG, RUN_STATE_CHECKPOINT_VM },
 
     { RUN_STATE_GUEST_PANICKED, RUN_STATE_PAUSED },
     { RUN_STATE_GUEST_PANICKED, RUN_STATE_FINISH_MIGRATE },
-- 
1.8.1.2