From 4a5c7884564b3dcbe354e594fe29a329a86af311 Mon Sep 17 00:00:00 2001 From: Pyun YongHyeon Date: Fri, 6 May 2011 23:49:10 +0000 Subject: [PATCH] Reuse the TX descriptor(DPD) if xl_encap() failed instead of just picking the next available one. This may explain why xl(4) sees TX underrun error with no queued frame. I hope this addresses a long standing xl(4) watchdog timeout issue as well. Obtained from: OpenBSD --- sys/dev/xl/if_xl.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/sys/dev/xl/if_xl.c b/sys/dev/xl/if_xl.c index e9384f886a3c..cc33caa482a3 100644 --- a/sys/dev/xl/if_xl.c +++ b/sys/dev/xl/if_xl.c @@ -2571,8 +2571,9 @@ static void xl_start_locked(struct ifnet *ifp) { struct xl_softc *sc = ifp->if_softc; - struct mbuf *m_head = NULL; + struct mbuf *m_head; struct xl_chain *prev = NULL, *cur_tx = NULL, *start_tx; + struct xl_chain *prev_tx; u_int32_t status; int error; @@ -2603,11 +2604,13 @@ xl_start_locked(struct ifnet *ifp) break; /* Pick a descriptor off the free list. */ + prev_tx = cur_tx; cur_tx = sc->xl_cdata.xl_tx_free; /* Pack the data into the descriptor. */ error = xl_encap(sc, cur_tx, &m_head); if (error) { + cur_tx = prev_tx; if (m_head == NULL) break; ifp->if_drv_flags |= IFF_DRV_OACTIVE; @@ -2702,8 +2705,9 @@ static void xl_start_90xB_locked(struct ifnet *ifp) { struct xl_softc *sc = ifp->if_softc; - struct mbuf *m_head = NULL; + struct mbuf *m_head; struct xl_chain *prev = NULL, *cur_tx = NULL, *start_tx; + struct xl_chain *prev_tx; int error, idx; XL_LOCK_ASSERT(sc); @@ -2726,11 +2730,13 @@ xl_start_90xB_locked(struct ifnet *ifp) if (m_head == NULL) break; + prev_tx = cur_tx; cur_tx = &sc->xl_cdata.xl_tx_chain[idx]; /* Pack the data into the descriptor. */ error = xl_encap(sc, cur_tx, &m_head); if (error) { + cur_tx = prev_tx; if (m_head == NULL) break; ifp->if_drv_flags |= IFF_DRV_OACTIVE;