Re: [Qemu-devel] [PATCH 3/3] colo-compare: use notifier to notify inconsistent packets comparing

[Hailiang Zhang]

On 2017/2/3 12:50, Jason Wang wrote:

On 2017年01月24日 22:05, zhanghailiang wrote:

It's a good idea to use notifier to notify COLO frame of
inconsistent packets comparing.

Signed-off-by: Zhang Chen <zhangchen.f...@cn.fujitsu.com>
Signed-off-by: zhanghailiang <zhang.zhanghaili...@huawei.com>
---
   net/colo-compare.c | 24 ++++++++++++++++++++++--
   net/colo-compare.h |  2 ++
   2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/net/colo-compare.c b/net/colo-compare.c
index 2ad577b..39c394d 100644
--- a/net/colo-compare.c
+++ b/net/colo-compare.c
@@ -30,6 +30,7 @@
   #include "qapi-visit.h"
   #include "net/colo.h"
   #include "net/colo-compare.h"
+#include "migration/migration.h"

   #define TYPE_COLO_COMPARE "colo-compare"
   #define COLO_COMPARE(obj) \
@@ -38,6 +39,9 @@
   static QTAILQ_HEAD(, CompareState) net_compares =
          QTAILQ_HEAD_INITIALIZER(net_compares);

+static NotifierList colo_compare_notifiers =
+    NOTIFIER_LIST_INITIALIZER(colo_compare_notifiers);
+
   #define COMPARE_READ_LEN_MAX NET_BUFSIZE
   #define MAX_QUEUE_SIZE 1024

@@ -378,6 +382,22 @@ static int colo_old_packet_check_one(Packet *pkt, int64_t 
*check_time)
       }
   }

+static void colo_compare_inconsistent_notify(void)
+{
+    notifier_list_notify(&colo_compare_notifiers,
+                migrate_get_current());
+}
+
+void colo_compare_register_notifier(Notifier *notify)
+{
+    notifier_list_add(&colo_compare_notifiers, notify);
+}
+
+void colo_compare_unregister_notifier(Notifier *notify)
+{
+    notifier_remove(notify);
+}
+
   static void colo_old_packet_check_one_conn(void *opaque,
                                              void *user_data)
   {
@@ -392,7 +412,7 @@ static void colo_old_packet_check_one_conn(void *opaque,
       qemu_mutex_unlock(&conn->conn_lock);
       if (result) {
           /* do checkpoint will flush old packet */
-        /* TODO: colo_notify_checkpoint();*/
+        colo_compare_inconsistent_notify();
       }
   }

@@ -466,7 +486,7 @@ static void colo_compare_connection(void *opaque, void 
*user_data)
                */
               trace_colo_compare_main("packet different");
               g_queue_push_tail(&conn->primary_list, pkt);
-            /* TODO: colo_notify_checkpoint();*/
+            colo_compare_inconsistent_notify();
               break;
           }
       }

I don't see any users for
colo_compare_register_notifier/colo_compare_unregister_notifier, is any
patch missed in this series?

No, we will use these functions in later series which integrate COLO compare
with COLO frame.
So, should i move this patch to the series where it is been called ?
patch 2 has the same problem.

And is it safe to do notification in colo thread?

Yes, the notification callback will be quite simple.

Thanks,
hailiang

Thanks

diff --git a/net/colo-compare.h b/net/colo-compare.h
index 44f9014..769f55a 100644
--- a/net/colo-compare.h
+++ b/net/colo-compare.h
@@ -16,5 +16,7 @@
   #define QEMU_COLO_COMPARE_H

   void colo_compare_do_checkpoint(void);
+void colo_compare_register_notifier(Notifier *notify);
+void colo_compare_unregister_notifier(Notifier *notify);

   #endif /* QEMU_COLO_COMPARE_H */

.