slirp: Remove unneeded if_queued

There is now a trivial check on entry of if_start for pending packets,
so we can drop the additional tracking via if_queued.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>

slirp/if.c

@@ -110,8 +110,6 @@ if_output(struct socket *so, struct mbuf *ifm)
 	insque(ifm, ifq);
 
 diddit:
-	slirp->if_queued++;
-
 	if (so) {
 		/* Update *_queued */
 		so->so_queued++;
@@ -157,7 +155,6 @@ diddit:
 void if_start(Slirp *slirp)
 {
     uint64_t now = qemu_get_clock_ns(rt_clock);
-    int requeued = 0;
     bool from_batchq, next_from_batchq;
     struct mbuf *ifm, *ifm_next, *ifqt;
 
@@ -182,8 +179,7 @@ void if_start(Slirp *slirp)
     while (ifm_next) {
         /* check if we can really output */
         if (!slirp_can_output(slirp->opaque)) {
-            slirp->if_start_busy = false;
-            return;
+            break;
         }
 
         ifm = ifm_next;
@@ -200,12 +196,9 @@ void if_start(Slirp *slirp)
             ifm_next = NULL;
         }
 
-        slirp->if_queued--;
-
         /* Try to send packet unless it already expired */
         if (ifm->expiration_date >= now && !if_encap(slirp, ifm)) {
             /* Packet is delayed due to pending ARP resolution */
-            requeued++;
             continue;
         }
 
@@ -245,7 +238,5 @@ void if_start(Slirp *slirp)
         m_free(ifm);
     }
 
-    slirp->if_queued = requeued;
-
     slirp->if_start_busy = false;
 }

slirp/slirp.c

@@ -581,13 +581,8 @@ void slirp_select_poll(fd_set *readfds, fd_set *writefds, fd_set *xfds,
                 }
 	}
 
-	/*
-	 * See if we can start outputting
-	 */
-	if (slirp->if_queued) {
         if_start(slirp);
     }
-    }
 
 	/* clear global file descriptor sets.
 	 * these reside on the stack in vl.c

slirp/slirp.h

@@ -235,7 +235,6 @@ struct Slirp {
     int mbuf_alloced;
 
     /* if states */
-    int if_queued;          /* number of packets queued so far */
     struct mbuf if_fastq;   /* fast queue (for interactive data) */
     struct mbuf if_batchq;  /* queue for non-interactive data */
     struct mbuf *next_m;    /* pointer to next mbuf to output */