[PULL 12/35] virtio-balloon: free page hinting cleanups

[Michael S. Tsirkin]

From: David Hildenbrand <david@redhat.com>

Let's compress the code a bit to improve readability. We can drop the
vm_running check in virtio_balloon_free_page_start() as it's already
properly checked in the single caller.

Cc: Wei Wang <wei.w.wang@intel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Cc: Alexander Duyck <alexander.duyck@gmail.com>
Cc: Juan Quintela <quintela@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210708095339.20274-3-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 hw/virtio/virtio-balloon.c | 28 ++++++++--------------------
 1 file changed, 8 insertions(+), 20 deletions(-)

diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
index ae7867a8db..5a69dce35d 100644
--- a/hw/virtio/virtio-balloon.c
+++ b/hw/virtio/virtio-balloon.c
@@ -534,22 +534,18 @@ static bool get_free_page_hints(VirtIOBalloon *dev)
         if (dev->free_page_hint_status == FREE_PAGE_HINT_S_REQUESTED &&
             id == dev->free_page_hint_cmd_id) {
             dev->free_page_hint_status = FREE_PAGE_HINT_S_START;
-        } else {
+        } else if (dev->free_page_hint_status == FREE_PAGE_HINT_S_START) {
             /*
              * Stop the optimization only when it has started. This
              * avoids a stale stop sign for the previous command.
              */
-            if (dev->free_page_hint_status == FREE_PAGE_HINT_S_START) {
-                dev->free_page_hint_status = FREE_PAGE_HINT_S_STOP;
-            }
+            dev->free_page_hint_status = FREE_PAGE_HINT_S_STOP;
         }
     }
 
-    if (elem->in_num) {
-        if (dev->free_page_hint_status == FREE_PAGE_HINT_S_START) {
-            qemu_guest_free_page_hint(elem->in_sg[0].iov_base,
-                                      elem->in_sg[0].iov_len);
-        }
+    if (elem->in_num && dev->free_page_hint_status == FREE_PAGE_HINT_S_START) {
+        qemu_guest_free_page_hint(elem->in_sg[0].iov_base,
+                                  elem->in_sg[0].iov_len);
     }
 
 out:
@@ -592,16 +588,10 @@ static void virtio_balloon_free_page_start(VirtIOBalloon 
*s)
 {
     VirtIODevice *vdev = VIRTIO_DEVICE(s);
 
-    /* For the stop and copy phase, we don't need to start the optimization */
-    if (!vdev->vm_running) {
-        return;
-    }
-
     qemu_mutex_lock(&s->free_page_lock);
 
     if (s->free_page_hint_cmd_id == UINT_MAX) {
-        s->free_page_hint_cmd_id =
-                       VIRTIO_BALLOON_FREE_PAGE_HINT_CMD_ID_MIN;
+        s->free_page_hint_cmd_id = VIRTIO_BALLOON_FREE_PAGE_HINT_CMD_ID_MIN;
     } else {
         s->free_page_hint_cmd_id++;
     }
@@ -649,8 +639,7 @@ static void virtio_balloon_free_page_done(VirtIOBalloon *s)
 static int
 virtio_balloon_free_page_hint_notify(NotifierWithReturn *n, void *data)
 {
-    VirtIOBalloon *dev = container_of(n, VirtIOBalloon,
-                                      free_page_hint_notify);
+    VirtIOBalloon *dev = container_of(n, VirtIOBalloon, free_page_hint_notify);
     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
     PrecopyNotifyData *pnd = data;
 
@@ -919,8 +908,7 @@ static void virtio_balloon_device_realize(DeviceState *dev, 
Error **errp)
     s->dvq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output);
     s->svq = virtio_add_queue(vdev, 128, virtio_balloon_receive_stats);
 
-    if (virtio_has_feature(s->host_features,
-                           VIRTIO_BALLOON_F_FREE_PAGE_HINT)) {
+    if (virtio_has_feature(s->host_features, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) 
{
         s->free_page_vq = virtio_add_queue(vdev, VIRTQUEUE_MAX_SIZE,
                                            virtio_balloon_handle_free_page_vq);
         precopy_add_notifier(&s->free_page_hint_notify);
-- 
MST