From 4348b96650bb03e0fa6cf5704ffc1a6517db4970 Mon Sep 17 00:00:00 2001 From: Michael Chan Date: Wed, 26 Sep 2018 00:41:04 -0400 Subject: bnxt_en: Fix TX timeout during netpoll. [ Upstream commit 73f21c653f930f438d53eed29b5e4c65c8a0f906 ] The current netpoll implementation in the bnxt_en driver has problems that may miss TX completion events. bnxt_poll_work() in effect is only handling at most 1 TX packet before exiting. In addition, there may be in flight TX completions that ->poll() may miss even after we fix bnxt_poll_work() to handle all visible TX completions. netpoll may not call ->poll() again and HW may not generate IRQ because the driver does not ARM the IRQ when the budget (0 for netpoll) is reached. We fix it by handling all TX completions and to always ARM the IRQ when we exit ->poll() with 0 budget. Also, the logic to ACK the completion ring in case it is almost filled with TX completions need to be adjusted to take care of the 0 budget case, as discussed with Eric Dumazet Reported-by: Song Liu Reviewed-by: Song Liu Tested-by: Song Liu Signed-off-by: Michael Chan Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) (limited to 'drivers/net/ethernet/broadcom/bnxt/bnxt.c') diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c index 4ffacafddacb..fea8116da06a 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -1343,8 +1343,11 @@ static int bnxt_poll_work(struct bnxt *bp, struct bnxt_napi *bnapi, int budget) if (TX_CMP_TYPE(txcmp) == CMP_TYPE_TX_L2_CMP) { tx_pkts++; /* return full budget so NAPI will complete. */ - if (unlikely(tx_pkts > bp->tx_wake_thresh)) + if (unlikely(tx_pkts > bp->tx_wake_thresh)) { rx_pkts = budget; + raw_cons = NEXT_RAW_CMP(raw_cons); + break; + } } else if ((TX_CMP_TYPE(txcmp) & 0x30) == 0x10) { rc = bnxt_rx_pkt(bp, bnapi, &raw_cons, &agg_event); if (likely(rc >= 0)) @@ -1362,7 +1365,7 @@ static int bnxt_poll_work(struct bnxt *bp, struct bnxt_napi *bnapi, int budget) } raw_cons = NEXT_RAW_CMP(raw_cons); - if (rx_pkts == budget) + if (rx_pkts && rx_pkts == budget) break; } @@ -1404,8 +1407,12 @@ static int bnxt_poll(struct napi_struct *napi, int budget) while (1) { work_done += bnxt_poll_work(bp, bnapi, budget - work_done); - if (work_done >= budget) + if (work_done >= budget) { + if (!budget) + BNXT_CP_DB_REARM(cpr->cp_doorbell, + cpr->cp_raw_cons); break; + } if (!bnxt_has_work(bp, cpr)) { napi_complete(napi); -- cgit v1.2.3