multifd: Fix flush of zero copy page send request

Make IO channel flush call after the inflight request has been drained in multifd thread, or else we may missed to flush the inflight request. Signed-off-by: Zhenzhong Duan <[email protected]> Reviewed-by: Juan Quintela <[email protected]> Signed-off-by: Juan Quintela <[email protected]>
jhamby · Feb 6, 2023 · ebfc578 · ebfc578
1 parent ddbe628
commit ebfc578
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Showing 4 changed files with 1,291 additions and 4 deletions.
diff --git a/configs/devices/x86_64-softmmu/x86_64-quintela-devices.mak b/configs/devices/x86_64-softmmu/x86_64-quintela-devices.mak
@@ -0,0 +1,7 @@
+# Boards:
+#
+CONFIG_ISAPC=n
+CONFIG_I440FX=n
+CONFIG_Q35=n
+CONFIG_MICROVM=y
+
diff --git a/configs/devices/x86_64-softmmu/x86_64-quintela2-devices.mak b/configs/devices/x86_64-softmmu/x86_64-quintela2-devices.mak
@@ -0,0 +1,6 @@
+# Boards:
+#
+CONFIG_ISAPC=y
+CONFIG_I440FX=y
+CONFIG_Q35=y
+CONFIG_MICROVM=y
diff --git a/migration/multifd.c b/migration/multifd.c
@@ -630,16 +630,16 @@ int multifd_send_sync_main(QEMUFile *f)
         stat64_add(&ram_atomic_counters.transferred, p->packet_len);
         qemu_mutex_unlock(&p->mutex);
         qemu_sem_post(&p->sem);
-
-        if (flush_zero_copy && p->c && (multifd_zero_copy_flush(p->c) < 0)) {
-            return -1;
-        }
     }
     for (i = 0; i < migrate_multifd_channels(); i++) {
         MultiFDSendParams *p = &multifd_send_state->params[i];
 
         trace_multifd_send_sync_main_wait(p->id);
         qemu_sem_wait(&p->sem_sync);
+
+        if (flush_zero_copy && p->c && (multifd_zero_copy_flush(p->c) < 0)) {
+            return -1;
+        }
     }
     trace_multifd_send_sync_main(multifd_send_state->packet_num);