migration: Use normal VMStateDescriptions for Subsections

We create optional sections with this patch.  But we already have
optional subsections.  Instead of having two mechanism that do the
same, we can just generalize it.

For subsections we just change:

- Add a needed function to VMStateDescription
- Remove VMStateSubsection (after removal of the needed function
  it is just a VMStateDescription)
- Adjust the whole tree, moving the needed function to the corresponding
  VMStateDescription

Signed-off-by: Juan Quintela <quintela@redhat.com>

2 files changed, 14 insertions, 20 deletions

diff --git a/hw/timer/hpet.c b/hw/timer/hpet.c
index b6b8a2063d..b50071ef93 100644
--- a/hw/timer/hpet.c
+++ b/hw/timer/hpet.c
@@ -283,6 +283,7 @@ static const VMStateDescription vmstate_hpet_rtc_irq_level = {
     .name = "hpet/rtc_irq_level",
     .version_id = 1,
     .minimum_version_id = 1,
+    .needed = hpet_rtc_irq_level_needed,
     .fields = (VMStateField[]) {
         VMSTATE_UINT8(rtc_irq_level, HPETState),
         VMSTATE_END_OF_LIST()
@@ -322,13 +323,9 @@ static const VMStateDescription vmstate_hpet = {
                                     vmstate_hpet_timer, HPETTimer),
         VMSTATE_END_OF_LIST()
     },
-    .subsections = (VMStateSubsection[]) {
-        {
-            .vmsd = &vmstate_hpet_rtc_irq_level,
-            .needed = hpet_rtc_irq_level_needed,
-        }, {
-            /* empty */
-        }
+    .subsections = (const VMStateDescription*[]) {
+        &vmstate_hpet_rtc_irq_level,
+        NULL
     }
 };
 
diff --git a/hw/timer/mc146818rtc.c b/hw/timer/mc146818rtc.c
index f2b77fa118..32048258c9 100644
--- a/hw/timer/mc146818rtc.c
+++ b/hw/timer/mc146818rtc.c
@@ -733,22 +733,23 @@ static int rtc_post_load(void *opaque, int version_id)
     return 0;
 }
 
+static bool rtc_irq_reinject_on_ack_count_needed(void *opaque)
+{
+    RTCState *s = (RTCState *)opaque;
+    return s->irq_reinject_on_ack_count != 0;
+}
+
 static const VMStateDescription vmstate_rtc_irq_reinject_on_ack_count = {
     .name = "mc146818rtc/irq_reinject_on_ack_count",
     .version_id = 1,
     .minimum_version_id = 1,
+    .needed = rtc_irq_reinject_on_ack_count_needed,
     .fields = (VMStateField[]) {
         VMSTATE_UINT16(irq_reinject_on_ack_count, RTCState),
         VMSTATE_END_OF_LIST()
     }
 };
 
-static bool rtc_irq_reinject_on_ack_count_needed(void *opaque)
-{
-    RTCState *s = (RTCState *)opaque;
-    return s->irq_reinject_on_ack_count != 0;
-}
-
 static const VMStateDescription vmstate_rtc = {
     .name = "mc146818rtc",
     .version_id = 3,
@@ -770,13 +771,9 @@ static const VMStateDescription vmstate_rtc = {
         VMSTATE_UINT64_V(next_alarm_time, RTCState, 3),
         VMSTATE_END_OF_LIST()
     },
-    .subsections = (VMStateSubsection[]) {
-        {
-            .vmsd = &vmstate_rtc_irq_reinject_on_ack_count,
-            .needed = rtc_irq_reinject_on_ack_count_needed,
-        }, {
-            /* empty */
-        }
+    .subsections = (const VMStateDescription*[]) {
+        &vmstate_rtc_irq_reinject_on_ack_count,
+        NULL
     }
 };