[Qemu-devel] [PATCH COLO-Frame v8 07/34] migration: Integrate COLO checkpoint process into loadvm

[zhanghailiang]

Switch from normal migration loadvm process into COLO checkpoint process if
COLO mode is enabled.
We add three new members to struct MigrationIncomingState, 
'have_colo_incoming_thread'
and 'colo_incoming_thread' record the colo related threads for secondary VM,
'migration_incoming_co' records the original migration incoming coroutine.

Signed-off-by: zhanghailiang <address@hidden>
Signed-off-by: Li Zhijian <address@hidden>
Signed-off-by: Yang Hongyang <address@hidden>
---
 include/migration/colo.h      |  8 ++++++++
 include/migration/migration.h |  7 +++++++
 migration/colo-comm.c         | 10 ++++++++++
 migration/colo.c              | 22 ++++++++++++++++++++++
 migration/migration.c         | 40 ++++++++++++++++++++++++++++++----------
 stubs/migration-colo.c        | 10 ++++++++++
 trace-events                  |  1 +
 7 files changed, 88 insertions(+), 10 deletions(-)

diff --git a/include/migration/colo.h b/include/migration/colo.h
index dface19..2559f90 100644
--- a/include/migration/colo.h
+++ b/include/migration/colo.h
@@ -15,6 +15,8 @@
 
 #include "qemu-common.h"
 #include "migration/migration.h"
+#include "block/coroutine.h"
+#include "qemu/thread.h"
 
 bool colo_supported(void);
 void colo_info_mig_init(void);
@@ -22,4 +24,10 @@ void colo_info_mig_init(void);
 void colo_init_checkpointer(MigrationState *s);
 bool migration_in_colo_state(void);
 
+/* loadvm */
+extern Coroutine *migration_incoming_co;
+bool migration_incoming_enable_colo(void);
+void migration_incoming_exit_colo(void);
+void *colo_process_incoming_checkpoints(void *opaque);
+bool migration_incoming_in_colo_state(void);
 #endif
diff --git a/include/migration/migration.h b/include/migration/migration.h
index 6fde8df..0548371 100644
--- a/include/migration/migration.h
+++ b/include/migration/migration.h
@@ -22,6 +22,7 @@
 #include "migration/vmstate.h"
 #include "qapi-types.h"
 #include "exec/cpu-common.h"
+#include "block/coroutine.h"
 
 #define QEMU_VM_FILE_MAGIC           0x5145564d
 #define QEMU_VM_FILE_VERSION_COMPAT  0x00000002
@@ -51,6 +52,12 @@ struct MigrationIncomingState {
     QEMUFile *file;
 
     int state;
+
+    bool have_colo_incoming_thread;
+    QemuThread colo_incoming_thread;
+    /* The coroutine we should enter (back) after failover */
+    Coroutine *migration_incoming_co;
+
     /* See savevm.c */
     LoadStateEntry_Head loadvm_handlers;
 };
diff --git a/migration/colo-comm.c b/migration/colo-comm.c
index 4330bd8..0808d6c 100644
--- a/migration/colo-comm.c
+++ b/migration/colo-comm.c
@@ -52,3 +52,13 @@ void colo_info_mig_init(void)
 {
     vmstate_register(NULL, 0, &colo_state, &colo_info);
 }
+
+bool migration_incoming_enable_colo(void)
+{
+    return colo_info.colo_requested;
+}
+
+void migration_incoming_exit_colo(void)
+{
+    colo_info.colo_requested = 0;
+}
diff --git a/migration/colo.c b/migration/colo.c
index 97e64a3..364e0dd 100644
--- a/migration/colo.c
+++ b/migration/colo.c
@@ -13,6 +13,7 @@
 #include "sysemu/sysemu.h"
 #include "migration/colo.h"
 #include "trace.h"
+#include "qemu/error-report.h"
 
 static QEMUBH *colo_bh;
 
@@ -28,6 +29,13 @@ bool migration_in_colo_state(void)
     return (s->state == MIGRATION_STATUS_COLO);
 }
 
+bool migration_incoming_in_colo_state(void)
+{
+    MigrationIncomingState *mis = migration_incoming_get_current();
+
+    return (mis && (mis->state == MIGRATION_STATUS_COLO));
+}
+
 static void *colo_thread(void *opaque)
 {
     MigrationState *s = opaque;
@@ -74,3 +82,17 @@ void colo_init_checkpointer(MigrationState *s)
     colo_bh = qemu_bh_new(colo_start_checkpointer, s);
     qemu_bh_schedule(colo_bh);
 }
+
+void *colo_process_incoming_checkpoints(void *opaque)
+{
+    MigrationIncomingState *mis = opaque;
+
+    migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
+                      MIGRATION_STATUS_COLO);
+
+    /* TODO: COLO checkpoint restore loop */
+
+    migration_incoming_exit_colo();
+
+    return NULL;
+}
diff --git a/migration/migration.c b/migration/migration.c
index a4a77b4..876c323 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -273,7 +273,29 @@ static void process_incoming_migration_co(void *opaque)
                       MIGRATION_STATUS_ACTIVE);
     ret = qemu_loadvm_state(f);
 
-    qemu_fclose(f);
+    if (!ret) {
+        /* Make sure all file formats flush their mutable metadata */
+        bdrv_invalidate_cache_all(&local_err);
+        if (local_err) {
+            error_report_err(local_err);
+            migrate_decompress_threads_join();
+            exit(EXIT_FAILURE);
+        }
+    }
+    /* we get colo info, and know if we are in colo mode */
+    if (!ret && migration_incoming_enable_colo()) {
+        mis->migration_incoming_co = qemu_coroutine_self();
+        qemu_thread_create(&mis->colo_incoming_thread, "colo incoming",
+             colo_process_incoming_checkpoints, mis, QEMU_THREAD_JOINABLE);
+        mis->have_colo_incoming_thread = true;
+        qemu_coroutine_yield();
+#if 0
+        /* FIXME  wait checkpoint incoming thread exit, and free resource */
+        qemu_thread_join(&mis->thread);
+#endif
+    } else {
+        qemu_fclose(f);
+    }
     free_xbzrle_decoded_buf();
     migration_incoming_state_destroy();
 
@@ -288,18 +310,9 @@ static void process_incoming_migration_co(void *opaque)
                       MIGRATION_STATUS_COMPLETED);
     qemu_announce_self();
 
-    /* Make sure all file formats flush their mutable metadata */
-    bdrv_invalidate_cache_all(&local_err);
-    if (local_err) {
-        error_report_err(local_err);
-        migrate_decompress_threads_join();
-        exit(EXIT_FAILURE);
-    }
-
     /* If global state section was not received or we are in running
        state, we need to obey autostart. Any other state is set with
        runstate_set. */
-
     if (!global_state_received() ||
         global_state_get_runstate() == RUN_STATE_RUNNING) {
         if (autostart) {
@@ -733,6 +746,13 @@ void qmp_migrate(const char *uri, bool has_blk, bool blk,
         error_setg(errp, QERR_MIGRATION_ACTIVE);
         return;
     }
+
+    if (migration_incoming_in_colo_state()) {
+        error_setg(errp, "Secondary VM is not allowed to do migration while"
+                   "in COLO status");
+        return;
+    }
+
     if (runstate_check(RUN_STATE_INMIGRATE)) {
         error_setg(errp, "Guest is waiting for an incoming migration");
         return;
diff --git a/stubs/migration-colo.c b/stubs/migration-colo.c
index 51b8f66..a105049 100644
--- a/stubs/migration-colo.c
+++ b/stubs/migration-colo.c
@@ -22,6 +22,16 @@ bool migration_in_colo_state(void)
     return false;
 }
 
+bool migration_incoming_in_colo_state(void)
+{
+    return false;
+}
+
 void colo_init_checkpointer(MigrationState *s)
 {
 }
+
+void *colo_process_incoming_checkpoints(void *opaque)
+{
+    return NULL;
+}
diff --git a/trace-events b/trace-events
index 3ea19ff..025d71c 100644
--- a/trace-events
+++ b/trace-events
@@ -1473,6 +1473,7 @@ 
rdma_start_outgoing_migration_after_rdma_source_init(void) ""
 
 # migration/colo.c
 colo_vm_state_change(const char *old, const char *new) "Change '%s' => '%s'"
+colo_receive_message(const char *msg) "Receive '%s'"
 
 # kvm-all.c
 kvm_ioctl(int type, void *arg) "type 0x%x, arg %p"
-- 
1.8.3.1