Remove the sc_soft_req_cnt field because the number of tx requests is

already tracked in sc_sendq. Replace the sc_flush logic with a simple
Fetch-and-Add store that avoids an unnecessary IOBDMA transaction.

ok uebayasi@

diff --git a/sys/arch/octeon/dev/if_cnmac.c b/sys/arch/octeon/dev/if_cnmac.c
index ec5520a..3bc333c 100644 (file)
--- a/sys/arch/octeon/dev/if_cnmac.c
+++ b/sys/arch/octeon/dev/if_cnmac.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if_cnmac.c,v 1.23 2015/06/11 12:30:42 jmatthew Exp $  */
+/*     $OpenBSD: if_cnmac.c,v 1.24 2015/10/08 14:24:32 visa Exp $      */
 
 /*
  * Copyright (c) 2007 Internet Initiative Japan, Inc.
@@ -144,7 +144,6 @@ int octeon_eth_mediachange(struct ifnet *);
 void   octeon_eth_send_queue_flush_prefetch(struct octeon_eth_softc *);
 void   octeon_eth_send_queue_flush_fetch(struct octeon_eth_softc *);
 void   octeon_eth_send_queue_flush(struct octeon_eth_softc *);
-void   octeon_eth_send_queue_flush_sync(struct octeon_eth_softc *);
 int    octeon_eth_send_queue_is_full(struct octeon_eth_softc *);
 void   octeon_eth_send_queue_add(struct octeon_eth_softc *,
            struct mbuf *, uint64_t *);
@@ -589,7 +588,6 @@ octeon_eth_send_queue_flush(struct octeon_eth_softc *sc)
        const int64_t sent_count = sc->sc_hard_done_cnt;
        int i;
 
-       OCTEON_ETH_KASSERT(sc->sc_flush == 0);
        OCTEON_ETH_KASSERT(sent_count <= 0);
 
        for (i = 0; i < 0 - sent_count; i++) {
@@ -603,25 +601,7 @@ octeon_eth_send_queue_flush(struct octeon_eth_softc *sc)
                m_freem(m);
        }
 
-       cn30xxfau_op_inc_fetch_8(&sc->sc_fau_done, i);
-       sc->sc_flush = i;
-}
-
-void
-octeon_eth_send_queue_flush_sync(struct octeon_eth_softc *sc)
-{
-       if (sc->sc_flush == 0)
-               return;
-
-       OCTEON_ETH_KASSERT(sc->sc_flush > 0);
-
-       /* XXX */
-       cn30xxfau_op_inc_read_8(&sc->sc_fau_done);
-       sc->sc_soft_req_cnt -= sc->sc_flush;
-       OCTEON_ETH_KASSERT(sc->sc_soft_req_cnt >= 0);
-       /* XXX */
-
-       sc->sc_flush = 0;
+       cn30xxfau_op_add_8(&sc->sc_fau_done, i);
 }
 
 int
@@ -630,11 +610,10 @@ octeon_eth_send_queue_is_full(struct octeon_eth_softc *sc)
 #ifdef OCTEON_ETH_SEND_QUEUE_CHECK
        int64_t nofree_cnt;
 
-       nofree_cnt = sc->sc_soft_req_cnt + sc->sc_hard_done_cnt; 
+       nofree_cnt = ml_len(&sc->sc_sendq) + sc->sc_hard_done_cnt; 
 
        if (__predict_false(nofree_cnt == GATHER_QUEUE_SIZE - 1)) {
                octeon_eth_send_queue_flush(sc);
-               octeon_eth_send_queue_flush_sync(sc);
                return 1;
        }
 
@@ -1073,7 +1052,7 @@ octeon_eth_start(struct ifnet *ifp)
                OCTEON_ETH_TAP(ifp, m, BPF_DIRECTION_OUT);
 
                /* XXX */
-               if (sc->sc_soft_req_cnt > sc->sc_soft_req_thresh)
+               if (ml_len(&sc->sc_sendq) > sc->sc_soft_req_thresh)
                        octeon_eth_send_queue_flush(sc);
                if (octeon_eth_send(sc, m)) {
                        ifp->if_oerrors++;
@@ -1081,11 +1060,7 @@ octeon_eth_start(struct ifnet *ifp)
                        log(LOG_WARNING,
                          "%s: failed to transmit packet\n",
                          sc->sc_dev.dv_xname);
-               } else {
-                       sc->sc_soft_req_cnt++;
                }
-               if (sc->sc_flush)
-                       octeon_eth_send_queue_flush_sync(sc);
                /* XXX */
 
                /*
@@ -1392,7 +1367,7 @@ octeon_eth_recv(struct octeon_eth_softc *sc, uint64_t *work)
         * performance tuning
         * presend iobdma request
         */
-       if (sc->sc_soft_req_cnt > sc->sc_soft_req_thresh) {
+       if (ml_len(&sc->sc_sendq) > sc->sc_soft_req_thresh) {
                octeon_eth_send_queue_flush_prefetch(sc);
        }
        /* XXX */
@@ -1426,15 +1401,11 @@ octeon_eth_recv(struct octeon_eth_softc *sc, uint64_t *work)
        cn30xxipd_offload(word2, m->m_data, &m->m_pkthdr.csum_flags);
 
        /* XXX */
-       if (sc->sc_soft_req_cnt > sc->sc_soft_req_thresh) {
+       if (ml_len(&sc->sc_sendq) > sc->sc_soft_req_thresh) {
                octeon_eth_send_queue_flush_fetch(sc);
                octeon_eth_send_queue_flush(sc);
        }
 
-       /* XXX */
-       if (sc->sc_flush)
-               octeon_eth_send_queue_flush_sync(sc);
-
        ml_enqueue(&ml, m);
        if_input(ifp, &ml);
 
@@ -1442,7 +1413,7 @@ octeon_eth_recv(struct octeon_eth_softc *sc, uint64_t *work)
 
 drop:
        /* XXX */
-       if (sc->sc_soft_req_cnt > sc->sc_soft_req_thresh) {
+       if (ml_len(&sc->sc_sendq) > sc->sc_soft_req_thresh) {
                octeon_eth_send_queue_flush_fetch(sc);
        }
        /* XXX */
@@ -1489,11 +1460,10 @@ octeon_eth_tick_free(void *arg)
 
        s = splnet();
        /* XXX */
-       if (sc->sc_soft_req_cnt > 0) {
+       if (ml_len(&sc->sc_sendq) > 0) {
                octeon_eth_send_queue_flush_prefetch(sc);
                octeon_eth_send_queue_flush_fetch(sc);
                octeon_eth_send_queue_flush(sc);
-               octeon_eth_send_queue_flush_sync(sc);
        }
        /* XXX */
 

diff --git a/sys/arch/octeon/dev/if_cnmacvar.h b/sys/arch/octeon/dev/if_cnmacvar.h
index 464aef2..06b985e 100644 (file)
--- a/sys/arch/octeon/dev/if_cnmacvar.h
+++ b/sys/arch/octeon/dev/if_cnmacvar.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if_cnmacvar.h,v 1.6 2015/06/11 12:30:42 jmatthew Exp $        */
+/*     $OpenBSD: if_cnmacvar.h,v 1.7 2015/10/08 14:24:32 visa Exp $    */
 
 /*
  * Copyright (c) 2007 Internet Initiative Japan, Inc.
@@ -76,10 +76,8 @@ struct octeon_eth_softc {
        struct timeout          sc_tick_free_ch;
        struct timeout          sc_resume_ch;
 
-       int64_t                 sc_soft_req_cnt;
        int64_t                 sc_soft_req_thresh;
        int64_t                 sc_hard_done_cnt;
-       int                     sc_flush;
        int                     sc_prefetch;
        struct mbuf_list        sc_sendq;
        uint64_t                sc_ext_callback_cnt;