On Thu, Jan 17, 2013 at 09:34:32PM +1100, Darren Tucker wrote:
> OK, here's another diff which does seem to help. It seems that there's
> two different bits in the TX descriptor that control interrupts. Quoting
> from the VT6105M spec:
Thanks to Mark Patruck for noticing that the previous patch didn't
actually help, due to a bug I introduced in a last minute "obviously
correct" clean up.
Index: dev/pci/if_vr.c
===================================================================
RCS file: /cvs/src/sys/dev/pci/if_vr.c,v
retrieving revision 1.124
diff -u -p -r1.124 if_vr.c
--- dev/pci/if_vr.c 16 Jan 2013 06:15:50 -0000 1.124
+++ dev/pci/if_vr.c 17 Jan 2013 21:54:19 -0000
@@ -724,7 +724,7 @@ vr_list_tx_init(struct vr_softc *sc)
cd = &sc->vr_cdata;
ld = sc->vr_ldata;
- cd->vr_tx_cnt = 0;
+ cd->vr_tx_cnt = cd->vr_tx_pkts = 0;
for (i = 0; i < VR_TX_LIST_CNT; i++) {
cd->vr_tx_chain[i].vr_ptr = &ld->vr_tx_list[i];
@@ -1292,7 +1292,15 @@ vr_encap(struct vr_softc *sc, struct vr_
}
/* Set EOP on the last descriptor */
- f->vr_ctl |= htole32(VR_TXCTL_LASTFRAG | VR_TXCTL_FINT);
+ f->vr_ctl |= htole32(VR_TXCTL_LASTFRAG);
+
+ /* set the disable-interrupt bit except on every Nth packet */
+ if (sc->vr_cdata.vr_tx_pkts++ < 8)
+ f->vr_next |= htole32(VR_TXNEXT_INTDISABLE);
+ else {
+ sc->vr_cdata.vr_tx_pkts = 0;
+ f->vr_ctl |= htole32(VR_TXCTL_FINT);
+ }
return (0);
}
@@ -1581,6 +1589,11 @@ vr_watchdog(struct ifnet *ifp)
struct vr_softc *sc;
sc = ifp->if_softc;
+
+ /* Reclaim first as we don't request an interrupt for every packet. */
+ vr_txeof(sc);
+ if (sc->vr_cdata.vr_tx_cnt == 0);
+ return;
ifp->if_oerrors++;
printf("%s: watchdog timeout\n", sc->sc_dev.dv_xname);
--
Darren Tucker (dtucker at zip.com.au)
GPG key 8FF4FA69 / D9A3 86E9 7EEE AF4B B2D4 37C9 C982 80C7 8FF4 FA69
Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.
