basically check for space on the ring before dequeuing the packet.
any errors we hit after that cause us to drop the mbuf.
ok?
Index: if_bge.c
===================================================================
RCS file: /cvs/src/sys/dev/pci/if_bge.c,v
retrieving revision 1.371
diff -u -p -r1.371 if_bge.c
--- if_bge.c 25 Oct 2015 13:04:28 -0000 1.371
+++ if_bge.c 11 Nov 2015 03:25:30 -0000
@@ -3985,7 +3985,7 @@ bge_cksum_pad(struct mbuf *m)
* pointers to descriptors.
*/
int
-bge_encap(struct bge_softc *sc, struct mbuf *m_head, int *txinc)
+bge_encap(struct bge_softc *sc, struct mbuf *m, int *txinc)
{
struct bge_tx_bd *f = NULL;
u_int32_t frag, cur;
@@ -3995,20 +3995,20 @@ bge_encap(struct bge_softc *sc, struct m
cur = frag = (sc->bge_tx_prodidx + *txinc) % BGE_TX_RING_CNT;
- if (m_head->m_pkthdr.csum_flags) {
- if (m_head->m_pkthdr.csum_flags & M_IPV4_CSUM_OUT)
+ if (m->m_pkthdr.csum_flags) {
+ if (m->m_pkthdr.csum_flags & M_IPV4_CSUM_OUT)
csum_flags |= BGE_TXBDFLAG_IP_CSUM;
- if (m_head->m_pkthdr.csum_flags & (M_TCP_CSUM_OUT |
- M_UDP_CSUM_OUT)) {
+ if (m->m_pkthdr.csum_flags &
+ (M_TCP_CSUM_OUT | M_UDP_CSUM_OUT)) {
csum_flags |= BGE_TXBDFLAG_TCP_UDP_CSUM;
- if (m_head->m_pkthdr.len < ETHER_MIN_NOPAD &&
- bge_cksum_pad(m_head) != 0)
+ if (m->m_pkthdr.len < ETHER_MIN_NOPAD &&
+ bge_cksum_pad(m) != 0)
return (ENOBUFS);
}
}
if (sc->bge_flags & BGE_JUMBO_FRAME &&
- m_head->m_pkthdr.len > ETHER_MAX_LEN)
+ m->m_pkthdr.len > ETHER_MAX_LEN)
csum_flags |= BGE_TXBDFLAG_JUMBO_FRAME;
if (!(BGE_CHIPREV(sc->bge_chipid) == BGE_CHIPREV_5700_BX))
@@ -4019,7 +4019,7 @@ bge_encap(struct bge_softc *sc, struct m
* less than eight bytes. If we encounter a teeny mbuf
* at the end of a chain, we can pad. Otherwise, copy.
*/
- if (bge_compact_dma_runt(m_head) != 0)
+ if (bge_compact_dma_runt(m) != 0)
return (ENOBUFS);
doit:
@@ -4030,13 +4030,13 @@ doit:
* the fragment pointers. Stop when we run out
* of fragments or hit the end of the mbuf chain.
*/
- switch (bus_dmamap_load_mbuf(sc->bge_dmatag, dmamap, m_head,
+ switch (bus_dmamap_load_mbuf(sc->bge_dmatag, dmamap, m,
BUS_DMA_NOWAIT)) {
case 0:
break;
case EFBIG:
- if (m_defrag(m_head, M_DONTWAIT) == 0 &&
- bus_dmamap_load_mbuf(sc->bge_dmatag, dmamap, m_head,
+ if (m_defrag(m, M_DONTWAIT) == 0 &&
+ bus_dmamap_load_mbuf(sc->bge_dmatag, dmamap, m,
BUS_DMA_NOWAIT) == 0)
break;
@@ -4045,10 +4045,6 @@ doit:
return (ENOBUFS);
}
- /* Check if we have enough free send BDs. */
- if (sc->bge_txcnt + *txinc + dmamap->dm_nsegs >= BGE_TX_RING_CNT)
- goto fail_unload;
-
for (i = 0; i < dmamap->dm_nsegs; i++) {
f = &sc->bge_rdata->bge_tx_ring[frag];
if (sc->bge_cdata.bge_tx_chain[frag] != NULL)
@@ -4058,9 +4054,9 @@ doit:
f->bge_flags = csum_flags;
f->bge_vlan_tag = 0;
#if NVLAN > 0
- if (m_head->m_flags & M_VLANTAG) {
+ if (m->m_flags & M_VLANTAG) {
f->bge_flags |= BGE_TXBDFLAG_VLAN_TAG;
- f->bge_vlan_tag = m_head->m_pkthdr.ether_vtag;
+ f->bge_vlan_tag = m->m_pkthdr.ether_vtag;
}
#endif
cur = frag;
@@ -4077,7 +4073,7 @@ doit:
goto fail_unload;
sc->bge_rdata->bge_tx_ring[cur].bge_flags |= BGE_TXBDFLAG_END;
- sc->bge_cdata.bge_tx_chain[cur] = m_head;
+ sc->bge_cdata.bge_tx_chain[cur] = m;
sc->bge_cdata.bge_tx_map[cur] = dmamap;
*txinc += dmamap->dm_nsegs;
@@ -4098,7 +4094,7 @@ void
bge_start(struct ifnet *ifp)
{
struct bge_softc *sc;
- struct mbuf *m_head;
+ struct mbuf *m;
int txinc;
sc = ifp->if_softc;
@@ -4110,25 +4106,28 @@ bge_start(struct ifnet *ifp)
txinc = 0;
while (1) {
- IFQ_POLL(&ifp->if_snd, m_head);
- if (m_head == NULL)
+ /* Check if we have enough free send BDs. */
+ if (sc->bge_txcnt + txinc + BGE_NTXSEG >= BGE_TX_RING_CNT) {
+ ifp->if_flags |= IFF_OACTIVE;
break;
+ }
- if (bge_encap(sc, m_head, &txinc))
+ IFQ_DEQUEUE(&ifp->if_snd, m);
+ if (m == NULL)
break;
- /* now we are committed to transmit the packet */
- IFQ_DEQUEUE(&ifp->if_snd, m_head);
+ if (bge_encap(sc, m, &txinc) != 0) {
+ m_freem(m);
+ continue;
+ }
#if NBPFILTER > 0
if (ifp->if_bpf)
- bpf_mtap_ether(ifp->if_bpf, m_head, BPF_DIRECTION_OUT);
+ bpf_mtap_ether(ifp->if_bpf, m, BPF_DIRECTION_OUT);
#endif
}
if (txinc != 0) {
- int txcnt;
-
/* Transmit */
sc->bge_tx_prodidx = (sc->bge_tx_prodidx + txinc) %
BGE_TX_RING_CNT;
@@ -4137,9 +4136,7 @@ bge_start(struct ifnet *ifp)
bge_writembx(sc, BGE_MBX_TX_HOST_PROD0_LO,
sc->bge_tx_prodidx);
- txcnt = atomic_add_int_nv(&sc->bge_txcnt, txinc);
- if (txcnt > BGE_TX_RING_CNT - 16)
- ifp->if_flags |= IFF_OACTIVE;
+ atomic_add_int(&sc->bge_txcnt, txinc);
/*
* Set a timeout in case the chip goes out to lunch.
