The main interesting bit here is the txeof and start loops, which previously
operated based on the prod/cons indices and the contents of the tx queue,
but now just uses the indices as that's the only way to get a consistent view
of the tx queue state.
At the moment I don't think the tx ring is big enough to use IFQ_DEQUEUE
instead of ifq_deq_begin/commit, but maybe I'm wrong about that.
can someone try this on an APU1?
Index: ic/re.c
===================================================================
RCS file: /cvs/src/sys/dev/ic/re.c,v
retrieving revision 1.187
diff -u -p -r1.187 re.c
--- ic/re.c 25 Nov 2015 03:09:58 -0000 1.187
+++ ic/re.c 4 Dec 2015 15:07:02 -0000
@@ -120,6 +120,7 @@
#include <sys/device.h>
#include <sys/timeout.h>
#include <sys/socket.h>
+#include <sys/atomic.h>
#include <machine/bus.h>
@@ -151,7 +152,7 @@ int redebug = 0;
static inline void re_set_bufaddr(struct rl_desc *, bus_addr_t);
-int re_encap(struct rl_softc *, struct mbuf *, int *);
+int re_encap(struct rl_softc *, struct mbuf *, struct rl_txq *, int *);
int re_newbuf(struct rl_softc *);
int re_rx_list_init(struct rl_softc *);
@@ -1448,18 +1449,14 @@ re_txeof(struct rl_softc *sc)
struct ifnet *ifp;
struct rl_txq *txq;
uint32_t txstat;
- int idx, descidx, tx = 0;
+ int idx, descidx, tx_free, freed = 0;
ifp = &sc->sc_arpcom.ac_if;
- for (idx = sc->rl_ldata.rl_txq_considx;; idx = RL_NEXT_TXQ(sc, idx)) {
+ for (idx = sc->rl_ldata.rl_txq_considx;
+ idx != sc->rl_ldata.rl_txq_prodidx; idx = RL_NEXT_TXQ(sc, idx)) {
txq = &sc->rl_ldata.rl_txq[idx];
- if (txq->txq_mbuf == NULL) {
- KASSERT(idx == sc->rl_ldata.rl_txq_prodidx);
- break;
- }
-
descidx = txq->txq_descidx;
RL_TXDESCSYNC(sc, descidx,
BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
@@ -1470,9 +1467,7 @@ re_txeof(struct rl_softc *sc)
if (txstat & RL_TDESC_CMD_OWN)
break;
- tx = 1;
- sc->rl_ldata.rl_tx_free += txq->txq_nsegs;
- KASSERT(sc->rl_ldata.rl_tx_free <= sc->rl_ldata.rl_tx_desc_cnt);
+ freed += txq->txq_nsegs;
bus_dmamap_sync(sc->sc_dmat, txq->txq_dmamap,
0, txq->txq_dmamap->dm_mapsize, BUS_DMASYNC_POSTWRITE);
bus_dmamap_unload(sc->sc_dmat, txq->txq_dmamap);
@@ -1487,9 +1482,13 @@ re_txeof(struct rl_softc *sc)
ifp->if_opackets++;
}
- sc->rl_ldata.rl_txq_considx = idx;
+ if (freed == 0)
+ return (0);
- ifq_clr_oactive(&ifp->if_snd);
+ tx_free = atomic_add_int_nv(&sc->rl_ldata.rl_tx_free, freed);
+ KASSERT(tx_free <= sc->rl_ldata.rl_tx_desc_cnt);
+
+ sc->rl_ldata.rl_txq_considx = idx;
/*
* Some chips will ignore a second TX request issued while an
@@ -1498,12 +1497,14 @@ re_txeof(struct rl_softc *sc)
* to restart the channel here to flush them out. This only
* seems to be required with the PCIe devices.
*/
- if (sc->rl_ldata.rl_tx_free < sc->rl_ldata.rl_tx_desc_cnt)
+ if (tx_free < sc->rl_ldata.rl_tx_desc_cnt)
CSR_WRITE_1(sc, sc->rl_txstart, RL_TXSTART_START);
- else
+ else {
+ ifq_clr_oactive(&ifp->if_snd);
ifp->if_timer = 0;
+ }
- return (tx);
+ return (1);
}
void
@@ -1566,7 +1567,9 @@ re_intr(void *arg)
}
if (status & RL_ISR_SYSTEM_ERR) {
+ KERNEL_LOCK();
re_init(ifp);
+ KERNEL_UNLOCK();
claimed = 1;
}
}
@@ -1599,7 +1602,11 @@ re_intr(void *arg)
}
}
- re_start(ifp);
+ if (!IFQ_IS_EMPTY(&ifp->if_snd)) {
+ KERNEL_LOCK();
+ re_start(ifp);
+ KERNEL_UNLOCK();
+ }
CSR_WRITE_2(sc, RL_IMR, sc->rl_intrs);
@@ -1607,7 +1614,7 @@ re_intr(void *arg)
}
int
-re_encap(struct rl_softc *sc, struct mbuf *m, int *idx)
+re_encap(struct rl_softc *sc, struct mbuf *m, struct rl_txq *txq, int *used)
{
bus_dmamap_t map;
struct mbuf *mp, mh;
@@ -1616,7 +1623,6 @@ re_encap(struct rl_softc *sc, struct mbu
struct ip *ip;
struct rl_desc *d;
u_int32_t cmdstat, vlanctl = 0, csum_flags = 0;
- struct rl_txq *txq;
/*
* Set up checksum offload. Note: checksum offload bits must
@@ -1669,7 +1675,6 @@ re_encap(struct rl_softc *sc, struct mbu
}
}
- txq = &sc->rl_ldata.rl_txq[*idx];
map = txq->txq_dmamap;
error = bus_dmamap_load_mbuf(sc->sc_dmat, map, m,
@@ -1710,7 +1715,7 @@ re_encap(struct rl_softc *sc, struct mbu
nsegs++;
}
- if (sc->rl_ldata.rl_tx_free - nsegs <= 1) {
+ if (sc->rl_ldata.rl_tx_free - (*used + nsegs) <= 1) {
error = EFBIG;
goto fail_unload;
}
@@ -1812,10 +1817,9 @@ re_encap(struct rl_softc *sc, struct mbu
txq->txq_descidx = lastidx;
txq->txq_nsegs = nsegs;
- sc->rl_ldata.rl_tx_free -= nsegs;
sc->rl_ldata.rl_tx_nextfree = curidx;
- *idx = RL_NEXT_TXQ(sc, *idx);
+ *used += nsegs;
return (0);
@@ -1834,30 +1838,25 @@ re_start(struct ifnet *ifp)
{
struct rl_softc *sc = ifp->if_softc;
struct mbuf *m;
- int idx, queued = 0, error;
+ int idx, used = 0, txq_free, error;
if (!(ifp->if_flags & IFF_RUNNING) || ifq_is_oactive(&ifp->if_snd))
return;
if ((sc->rl_flags & RL_FLAG_LINK) == 0)
return;
- if (IFQ_IS_EMPTY(&ifp->if_snd))
- return;
+ txq_free = sc->rl_ldata.rl_txq_considx;
idx = sc->rl_ldata.rl_txq_prodidx;
+ if (idx >= txq_free)
+ txq_free += RL_TX_QLEN;
+ txq_free -= idx;
- for (;;) {
+ while (txq_free > 1) {
m = ifq_deq_begin(&ifp->if_snd);
if (m == NULL)
break;
- if (sc->rl_ldata.rl_txq[idx].txq_mbuf != NULL) {
- KASSERT(idx == sc->rl_ldata.rl_txq_considx);
- ifq_deq_rollback(&ifp->if_snd, m);
- ifq_set_oactive(&ifp->if_snd);
- break;
- }
-
- error = re_encap(sc, m, &idx);
+ error = re_encap(sc, m, &sc->rl_ldata.rl_txq[idx], &used);
if (error != 0 && error != ENOBUFS) {
ifq_deq_rollback(&ifp->if_snd, m);
ifq_set_oactive(&ifp->if_snd);
@@ -1869,31 +1868,25 @@ re_start(struct ifnet *ifp)
continue;
}
- /* now we are committed to transmit the packet */
ifq_deq_commit(&ifp->if_snd, m);
- queued++;
#if NBPFILTER > 0
- /*
- * If there's a BPF listener, bounce a copy of this frame
- * to him.
- */
if (ifp->if_bpf)
bpf_mtap_ether(ifp->if_bpf, m, BPF_DIRECTION_OUT);
#endif
+ idx = RL_NEXT_TXQ(sc, idx);
+ txq_free--;
}
- if (queued == 0)
+ if (used == 0)
return;
-
+
+ ifp->if_timer = 5;
sc->rl_ldata.rl_txq_prodidx = idx;
+ atomic_sub_int(&sc->rl_ldata.rl_tx_free, used);
+ KASSERT(sc->rl_ldata.rl_tx_free >= 0);
CSR_WRITE_1(sc, sc->rl_txstart, RL_TXSTART_START);
-
- /*
- * Set a timeout in case the chip goes out to lunch.
- */
- ifp->if_timer = 5;
}
int
@@ -2148,8 +2141,6 @@ re_stop(struct ifnet *ifp)
ifp->if_flags &= ~IFF_RUNNING;
ifq_clr_oactive(&ifp->if_snd);
- mii_down(&sc->sc_mii);
-
/*
* Disable accepting frames to put RX MAC into idle state.
* Otherwise it's possible to get frames while stop command
@@ -2195,6 +2186,10 @@ re_stop(struct ifnet *ifp)
m_freem(sc->rl_head);
sc->rl_head = sc->rl_tail = NULL;
}
+
+ intr_barrier(sc->sc_ih);
+
+ mii_down(&sc->sc_mii);
/* Free the TX list buffers. */
for (i = 0; i < RL_TX_QLEN; i++) {
Index: pci/if_re_pci.c
===================================================================
RCS file: /cvs/src/sys/dev/pci/if_re_pci.c,v
retrieving revision 1.49
diff -u -p -r1.49 if_re_pci.c
--- pci/if_re_pci.c 24 Nov 2015 17:11:39 -0000 1.49
+++ pci/if_re_pci.c 4 Dec 2015 15:07:02 -0000
@@ -156,8 +156,8 @@ re_pci_attach(struct device *parent, str
return;
}
intrstr = pci_intr_string(pc, ih);
- psc->sc_ih = pci_intr_establish(pc, ih, IPL_NET, re_intr, sc,
- sc->sc_dev.dv_xname);
+ psc->sc_ih = pci_intr_establish(pc, ih, IPL_NET | IPL_MPSAFE, re_intr,
+ sc, sc->sc_dev.dv_xname);
if (psc->sc_ih == NULL) {
printf(": couldn't establish interrupt");
if (intrstr != NULL)
