在 2021/5/17 下午9:04, Pavel Dovgalyuk 写道:
virtio-net device uses bottom halves for callbacks.
These callbacks should be deterministic, because they affect VM state.
This patch replaces BH invocations with corresponding replay functions,
making them deterministic in record/replay mode.
This patch also disables guest announce timers for record/replay,
because they break correct loadvm in deterministic mode.


Virtio-net can be configured to work in tx timer mode. Do we need to care about that?


Signed-off-by: Pavel Dovgalyuk <pavel.dovgal...@ispras.ru>
---
  hw/net/virtio-net.c |   13 +++++++++----
  1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index 6b7e8dd04e..e876363236 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -44,6 +44,7 @@
  #include "hw/pci/pci.h"
  #include "net_rx_pkt.h"
  #include "hw/virtio/vhost.h"
+#include "sysemu/replay.h"
#define VIRTIO_NET_VM_VERSION 11 @@ -394,7 +395,7 @@ static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status)
                  timer_mod(q->tx_timer,
                                 qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 
n->tx_timeout);
              } else {
-                qemu_bh_schedule(q->tx_bh);
+                replay_bh_schedule_event(q->tx_bh);
              }
          } else {
              if (q->tx_timer) {
@@ -2546,7 +2547,7 @@ static void virtio_net_handle_tx_bh(VirtIODevice *vdev, 
VirtQueue *vq)
          return;
      }
      virtio_queue_set_notification(vq, 0);
-    qemu_bh_schedule(q->tx_bh);
+    replay_bh_schedule_event(q->tx_bh);


Not familiar with replay but any chance to change qemu_bh_schedule() instead?

Thanks


  }
static void virtio_net_tx_timer(void *opaque)
@@ -2602,7 +2603,7 @@ static void virtio_net_tx_bh(void *opaque)
      /* If we flush a full burst of packets, assume there are
       * more coming and immediately reschedule */
      if (ret >= n->tx_burst) {
-        qemu_bh_schedule(q->tx_bh);
+        replay_bh_schedule_event(q->tx_bh);
          q->tx_waiting = 1;
          return;
      }
@@ -2616,7 +2617,7 @@ static void virtio_net_tx_bh(void *opaque)
          return;
      } else if (ret > 0) {
          virtio_queue_set_notification(q->tx_vq, 0);
-        qemu_bh_schedule(q->tx_bh);
+        replay_bh_schedule_event(q->tx_bh);
          q->tx_waiting = 1;
      }
  }
@@ -3206,6 +3207,10 @@ static void virtio_net_device_realize(DeviceState *dev, 
Error **errp)
          n->host_features |= (1ULL << VIRTIO_NET_F_MTU);
      }
+ if (replay_mode != REPLAY_MODE_NONE) {
+        n->host_features &= ~(1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE);
+    }
+
      if (n->net_conf.duplex_str) {
          if (strncmp(n->net_conf.duplex_str, "half", 5) == 0) {
              n->net_conf.duplex = DUPLEX_HALF;




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