Remove top level ring processing loops as too ambiguous

diff --git a/sys/dev/pv/if_xnf.c b/sys/dev/pv/if_xnf.c
index 2494772..1d8f2c4 100644 (file)
--- a/sys/dev/pv/if_xnf.c
+++ b/sys/dev/pv/if_xnf.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if_xnf.c,v 1.23 2016/07/28 12:08:14 mikeb Exp $       */
+/*     $OpenBSD: if_xnf.c,v 1.24 2016/07/28 17:35:13 mikeb Exp $       */
 
 /*
  * Copyright (c) 2015, 2016 Mike Belopuhov
@@ -632,50 +632,41 @@ xnf_txeof(struct xnf_softc *sc)
        union xnf_tx_desc *txd;
        struct mbuf *m;
        bus_dmamap_t dmap;
-       volatile uint32_t r;
        uint32_t cons;
-       int i, id, pkts = 0;
+       int i, id;
 
        bus_dmamap_sync(sc->sc_dmat, sc->sc_tx_rmap, 0, 0,
            BUS_DMASYNC_POSTWRITE);
 
-       do {
-               for (cons = sc->sc_tx_cons; cons != txr->txr_cons; cons++) {
-                       i = cons & (XNF_TX_DESC - 1);
-                       txd = &txr->txr_desc[i];
-                       dmap = sc->sc_tx_dmap[i];
-
-                       id = txd->txd_rsp.txp_id;
-                       memset(txd, 0, sizeof(*txd));
-                       txd->txd_req.txq_id = id;
-
-                       m = sc->sc_tx_buf[i];
-                       KASSERT(m != NULL);
-                       sc->sc_tx_buf[i] = NULL;
-
-                       bus_dmamap_sync(sc->sc_dmat, dmap, 0, 0,
-                           BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
-                       bus_dmamap_unload(sc->sc_dmat, dmap);
-                       m_free(m);
-                       pkts++;
-               }
+       for (cons = sc->sc_tx_cons; cons != txr->txr_cons; cons++) {
+               i = cons & (XNF_TX_DESC - 1);
+               txd = &txr->txr_desc[i];
+               dmap = sc->sc_tx_dmap[i];
 
-               if (pkts > 0) {
-                       sc->sc_tx_cons = cons;
-                       txr->txr_cons_event = cons +
-                           ((txr->txr_prod - cons) >> 1) + 1;
-                       bus_dmamap_sync(sc->sc_dmat, sc->sc_tx_rmap, 0, 0,
-                           BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
-                       pkts = 0;
-               }
+               id = txd->txd_rsp.txp_id;
+               memset(txd, 0, sizeof(*txd));
+               txd->txd_req.txq_id = id;
 
-               r = txr->txr_cons - sc->sc_tx_cons;
-       } while (r > 0);
+               m = sc->sc_tx_buf[i];
+               KASSERT(m != NULL);
+               sc->sc_tx_buf[i] = NULL;
 
+               bus_dmamap_sync(sc->sc_dmat, dmap, 0, 0,
+                   BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
+               bus_dmamap_unload(sc->sc_dmat, dmap);
+               m_free(m);
+       }
+
+       sc->sc_tx_cons = cons;
+       txr->txr_cons_event = sc->sc_tx_cons +
+           ((txr->txr_prod - sc->sc_tx_cons) >> 1) + 1;
+       bus_dmamap_sync(sc->sc_dmat, sc->sc_tx_rmap, 0, 0,
+           BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
+
+       if (txr->txr_cons == txr->txr_prod)
+               ifp->if_timer = 0;
        if (ifq_is_oactive(&ifp->if_snd))
                ifq_restart(&ifp->if_snd);
-       else if (txr->txr_cons == txr->txr_prod)
-               ifp->if_timer = 0;
 
        return (0);
 }
@@ -691,93 +682,86 @@ xnf_rxeof(struct xnf_softc *sc)
        struct mbuf *lmp = sc->sc_rx_cbuf[1];
        struct mbuf *m;
        bus_dmamap_t dmap;
-       volatile uint32_t r;
        uint32_t cons;
-       int i, id, flags, len, offset, pkts = 0;
+       int i, id, flags, len, offset;
 
        bus_dmamap_sync(sc->sc_dmat, sc->sc_rx_rmap, 0, 0,
            BUS_DMASYNC_POSTREAD);
 
-       do {
-               for (cons = sc->sc_rx_cons; cons != rxr->rxr_cons; cons++) {
-                       i = cons & (XNF_RX_DESC - 1);
-                       rxd = &rxr->rxr_desc[i];
-                       dmap = sc->sc_rx_dmap[i];
-
-                       len = rxd->rxd_rsp.rxp_status;
-                       flags = rxd->rxd_rsp.rxp_flags;
-                       offset = rxd->rxd_rsp.rxp_offset;
-                       id = rxd->rxd_rsp.rxp_id;
-                       memset(rxd, 0, sizeof(*rxd));
-                       rxd->rxd_req.rxq_id = id;
-
-                       bus_dmamap_sync(sc->sc_dmat, dmap, 0, 0,
-                           BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
-                       bus_dmamap_unload(sc->sc_dmat, dmap);
-
-                       m = sc->sc_rx_buf[i];
-                       KASSERT(m != NULL);
-                       sc->sc_rx_buf[i] = NULL;
-
-                       if (flags & XNF_RXF_MGMT)
-                               printf("%s: management data present\n",
-                                   ifp->if_xname);
-
-                       if (flags & XNF_RXF_CSUM_VALID)
-                               m->m_pkthdr.csum_flags = M_TCP_CSUM_IN_OK |
-                                   M_UDP_CSUM_IN_OK;
-
-                       if_rxr_put(&sc->sc_rx_slots, 1);
-                       pkts++;
-
-                       if (len < 0 || (len + offset > PAGE_SIZE)) {
-                               ifp->if_ierrors++;
-                               m_freem(m);
-                               continue;
-                       }
-
-                       m->m_len = len;
-                       m->m_data += offset;
-
-                       if (fmp == NULL) {
-                               m->m_pkthdr.len = len;
-                               fmp = m;
-                       } else {
-                               m->m_flags &= ~M_PKTHDR;
-                               lmp->m_next = m;
-                               fmp->m_pkthdr.len += m->m_len;
-                       }
-                       lmp = m;
-
-                       if (flags & XNF_RXF_CHUNK) {
-                               sc->sc_rx_cbuf[0] = fmp;
-                               sc->sc_rx_cbuf[1] = lmp;
-                               continue;
-                       }
-
-                       m = fmp;
-
-                       ml_enqueue(&ml, m);
-                       sc->sc_rx_cbuf[0] = sc->sc_rx_cbuf[1] =
-                           fmp = lmp = NULL;
+       for (cons = sc->sc_rx_cons; cons != rxr->rxr_cons; cons++) {
+               i = cons & (XNF_RX_DESC - 1);
+               rxd = &rxr->rxr_desc[i];
+               dmap = sc->sc_rx_dmap[i];
+
+               len = rxd->rxd_rsp.rxp_status;
+               flags = rxd->rxd_rsp.rxp_flags;
+               offset = rxd->rxd_rsp.rxp_offset;
+               id = rxd->rxd_rsp.rxp_id;
+               memset(rxd, 0, sizeof(*rxd));
+               rxd->rxd_req.rxq_id = id;
+
+               bus_dmamap_sync(sc->sc_dmat, dmap, 0, 0,
+                   BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
+               bus_dmamap_unload(sc->sc_dmat, dmap);
+
+               m = sc->sc_rx_buf[i];
+               KASSERT(m != NULL);
+               sc->sc_rx_buf[i] = NULL;
+
+               if_rxr_put(&sc->sc_rx_slots, 1);
+
+               if (flags & XNF_RXF_MGMT) {
+                       printf("%s: management data present\n",
+                           ifp->if_xname);
+                       m_freem(m);
+                       continue;
                }
 
-               if (pkts > 0) {
-                       sc->sc_rx_cons = cons;
-                       rxr->rxr_cons_event = cons + 1;
-                       bus_dmamap_sync(sc->sc_dmat, sc->sc_rx_rmap, 0, 0,
-                           BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
-                       pkts = 0;
+               if (flags & XNF_RXF_CSUM_VALID)
+                       m->m_pkthdr.csum_flags = M_TCP_CSUM_IN_OK |
+                           M_UDP_CSUM_IN_OK;
+
+               if (len < 0 || (len + offset > PAGE_SIZE)) {
+                       ifp->if_ierrors++;
+                       m_freem(m);
+                       continue;
                }
 
-               r = rxr->rxr_cons - sc->sc_rx_cons;
-       } while (r > 0);
+               m->m_len = len;
+               m->m_data += offset;
 
-       if (!ml_empty(&ml)) {
-               if_input(ifp, &ml);
-               xnf_rx_ring_fill(sc);
+               if (fmp == NULL) {
+                       m->m_pkthdr.len = len;
+                       fmp = m;
+               } else {
+                       m->m_flags &= ~M_PKTHDR;
+                       lmp->m_next = m;
+                       fmp->m_pkthdr.len += m->m_len;
+               }
+               lmp = m;
+
+               if (flags & XNF_RXF_CHUNK) {
+                       sc->sc_rx_cbuf[0] = fmp;
+                       sc->sc_rx_cbuf[1] = lmp;
+                       continue;
+               }
+
+               m = fmp;
+
+               ml_enqueue(&ml, m);
+               sc->sc_rx_cbuf[0] = sc->sc_rx_cbuf[1] = fmp = lmp = NULL;
        }
 
+       sc->sc_rx_cons = cons;
+       rxr->rxr_cons_event = sc->sc_rx_cons + 1;
+       bus_dmamap_sync(sc->sc_dmat, sc->sc_rx_rmap, 0, 0,
+           BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
+
+       xnf_rx_ring_fill(sc);
+
+       if (!ml_empty(&ml))
+               if_input(ifp, &ml);
+
        return (0);
 }