diff options
-rw-r--r-- | drivers/net/ethernet/amazon/ena/ena_ethtool.c | 1 | ||||
-rw-r--r-- | drivers/net/ethernet/amazon/ena/ena_netdev.c | 55 | ||||
-rw-r--r-- | drivers/net/ethernet/amazon/ena/ena_netdev.h | 2 |
3 files changed, 58 insertions, 0 deletions
diff --git a/drivers/net/ethernet/amazon/ena/ena_ethtool.c b/drivers/net/ethernet/amazon/ena/ena_ethtool.c index 67b2338f8fb3..533b2fbdeef1 100644 --- a/drivers/net/ethernet/amazon/ena/ena_ethtool.c +++ b/drivers/net/ethernet/amazon/ena/ena_ethtool.c @@ -94,6 +94,7 @@ static const struct ena_stats ena_stats_rx_strings[] = { ENA_STAT_RX_ENTRY(dma_mapping_err), ENA_STAT_RX_ENTRY(bad_desc_num), ENA_STAT_RX_ENTRY(rx_copybreak_pkt), + ENA_STAT_RX_ENTRY(empty_rx_ring), }; static const struct ena_stats ena_stats_ena_com_strings[] = { diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c index 4e9fbddd3b47..3c366bfbbab1 100644 --- a/drivers/net/ethernet/amazon/ena/ena_netdev.c +++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c @@ -190,6 +190,7 @@ static void ena_init_io_rings(struct ena_adapter *adapter) rxr->sgl_size = adapter->max_rx_sgl_size; rxr->smoothed_interval = ena_com_get_nonadaptive_moderation_interval_rx(ena_dev); + rxr->empty_rx_queue = 0; } } @@ -2619,6 +2620,58 @@ static void check_for_missing_tx_completions(struct ena_adapter *adapter) adapter->last_monitored_tx_qid = i % adapter->num_queues; } +/* trigger napi schedule after 2 consecutive detections */ +#define EMPTY_RX_REFILL 2 +/* For the rare case where the device runs out of Rx descriptors and the + * napi handler failed to refill new Rx descriptors (due to a lack of memory + * for example). + * This case will lead to a deadlock: + * The device won't send interrupts since all the new Rx packets will be dropped + * The napi handler won't allocate new Rx descriptors so the device will be + * able to send new packets. + * + * This scenario can happen when the kernel's vm.min_free_kbytes is too small. + * It is recommended to have at least 512MB, with a minimum of 128MB for + * constrained environment). + * + * When such a situation is detected - Reschedule napi + */ +static void check_for_empty_rx_ring(struct ena_adapter *adapter) +{ + struct ena_ring *rx_ring; + int i, refill_required; + + if (!test_bit(ENA_FLAG_DEV_UP, &adapter->flags)) + return; + + if (test_bit(ENA_FLAG_TRIGGER_RESET, &adapter->flags)) + return; + + for (i = 0; i < adapter->num_queues; i++) { + rx_ring = &adapter->rx_ring[i]; + + refill_required = + ena_com_sq_empty_space(rx_ring->ena_com_io_sq); + if (unlikely(refill_required == (rx_ring->ring_size - 1))) { + rx_ring->empty_rx_queue++; + + if (rx_ring->empty_rx_queue >= EMPTY_RX_REFILL) { + u64_stats_update_begin(&rx_ring->syncp); + rx_ring->rx_stats.empty_rx_ring++; + u64_stats_update_end(&rx_ring->syncp); + + netif_err(adapter, drv, adapter->netdev, + "trigger refill for ring %d\n", i); + + napi_schedule(rx_ring->napi); + rx_ring->empty_rx_queue = 0; + } + } else { + rx_ring->empty_rx_queue = 0; + } + } +} + /* Check for keep alive expiration */ static void check_for_missing_keep_alive(struct ena_adapter *adapter) { @@ -2673,6 +2726,8 @@ static void ena_timer_service(unsigned long data) check_for_missing_tx_completions(adapter); + check_for_empty_rx_ring(adapter); + if (debug_area) ena_dump_stats_to_buf(adapter, debug_area); diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.h b/drivers/net/ethernet/amazon/ena/ena_netdev.h index 0e22bce6239d..8828f1d6dd22 100644 --- a/drivers/net/ethernet/amazon/ena/ena_netdev.h +++ b/drivers/net/ethernet/amazon/ena/ena_netdev.h @@ -184,6 +184,7 @@ struct ena_stats_rx { u64 dma_mapping_err; u64 bad_desc_num; u64 rx_copybreak_pkt; + u64 empty_rx_ring; }; struct ena_ring { @@ -231,6 +232,7 @@ struct ena_ring { struct ena_stats_tx tx_stats; struct ena_stats_rx rx_stats; }; + int empty_rx_queue; } ____cacheline_aligned; struct ena_stats_dev { |