| Message ID | 20240410091358.16289-3-darinzon@amazon.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | f7e417180665234fdb7af2ebe33d89aaa434d16f |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | ENA driver bug fixes | expand |
On 4/10/2024 2:13 AM, darinzon@amazon.com wrote: > From: David Arinzon <darinzon@amazon.com> > > Missing IO completions check is called every second (HZ jiffies). > This commit fixes several issues with this check: > > 1. Duplicate queues check: > Max of 4 queues are scanned on each check due to monitor budget. > Once reaching the budget, this check exits under the assumption that > the next check will continue to scan the remainder of the queues, > but in practice, next check will first scan the last already scanned > queue which is not necessary and may cause the full queue scan to > last a couple of seconds longer. > The fix is to start every check with the next queue to scan. > For example, on 8 IO queues: > Bug: [0,1,2,3], [3,4,5,6], [6,7] > Fix: [0,1,2,3], [4,5,6,7] > > 2. Unbalanced queues check: > In case the number of active IO queues is not a multiple of budget, > there will be checks which don't utilize the full budget > because the full scan exits when reaching the last queue id. > The fix is to run every TX completion check with exact queue budget > regardless of the queue id. > For example, on 7 IO queues: > Bug: [0,1,2,3], [4,5,6], [0,1,2,3] > Fix: [0,1,2,3], [4,5,6,0], [1,2,3,4] > The budget may be lowered in case the number of IO queues is less > than the budget (4) to make sure there are no duplicate queues on > the same check. > For example, on 3 IO queues: > Bug: [0,1,2,0], [1,2,0,1] > Fix: [0,1,2], [0,1,2] > > Fixes: 1738cd3ed342 ("net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)") > Signed-off-by: Amit Bernstein <amitbern@amazon.com> > Signed-off-by: David Arinzon <darinzon@amazon.com> Reviewed-by: Shannon Nelson <shannon.nelson@amd.com> > --- > drivers/net/ethernet/amazon/ena/ena_netdev.c | 21 +++++++++++--------- > 1 file changed, 12 insertions(+), 9 deletions(-) > > diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c > index 09e7da1a..59befc0f 100644 > --- a/drivers/net/ethernet/amazon/ena/ena_netdev.c > +++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c > @@ -3481,10 +3481,11 @@ static void check_for_missing_completions(struct ena_adapter *adapter) > { > struct ena_ring *tx_ring; > struct ena_ring *rx_ring; > - int i, budget, rc; > + int qid, budget, rc; > int io_queue_count; > > io_queue_count = adapter->xdp_num_queues + adapter->num_io_queues; > + > /* Make sure the driver doesn't turn the device in other process */ > smp_rmb(); > > @@ -3497,27 +3498,29 @@ static void check_for_missing_completions(struct ena_adapter *adapter) > if (adapter->missing_tx_completion_to == ENA_HW_HINTS_NO_TIMEOUT) > return; > > - budget = ENA_MONITORED_TX_QUEUES; > + budget = min_t(u32, io_queue_count, ENA_MONITORED_TX_QUEUES); > > - for (i = adapter->last_monitored_tx_qid; i < io_queue_count; i++) { > - tx_ring = &adapter->tx_ring[i]; > - rx_ring = &adapter->rx_ring[i]; > + qid = adapter->last_monitored_tx_qid; > + > + while (budget) { > + qid = (qid + 1) % io_queue_count; > + > + tx_ring = &adapter->tx_ring[qid]; > + rx_ring = &adapter->rx_ring[qid]; > > rc = check_missing_comp_in_tx_queue(adapter, tx_ring); > if (unlikely(rc)) > return; > > - rc = !ENA_IS_XDP_INDEX(adapter, i) ? > + rc = !ENA_IS_XDP_INDEX(adapter, qid) ? > check_for_rx_interrupt_queue(adapter, rx_ring) : 0; > if (unlikely(rc)) > return; > > budget--; > - if (!budget) > - break; > } > > - adapter->last_monitored_tx_qid = i % io_queue_count; > + adapter->last_monitored_tx_qid = qid; > } > > /* trigger napi schedule after 2 consecutive detections */ > -- > 2.40.1 > >
diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c index 09e7da1a..59befc0f 100644 --- a/drivers/net/ethernet/amazon/ena/ena_netdev.c +++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c @@ -3481,10 +3481,11 @@ static void check_for_missing_completions(struct ena_adapter *adapter) { struct ena_ring *tx_ring; struct ena_ring *rx_ring; - int i, budget, rc; + int qid, budget, rc; int io_queue_count; io_queue_count = adapter->xdp_num_queues + adapter->num_io_queues; + /* Make sure the driver doesn't turn the device in other process */ smp_rmb(); @@ -3497,27 +3498,29 @@ static void check_for_missing_completions(struct ena_adapter *adapter) if (adapter->missing_tx_completion_to == ENA_HW_HINTS_NO_TIMEOUT) return; - budget = ENA_MONITORED_TX_QUEUES; + budget = min_t(u32, io_queue_count, ENA_MONITORED_TX_QUEUES); - for (i = adapter->last_monitored_tx_qid; i < io_queue_count; i++) { - tx_ring = &adapter->tx_ring[i]; - rx_ring = &adapter->rx_ring[i]; + qid = adapter->last_monitored_tx_qid; + + while (budget) { + qid = (qid + 1) % io_queue_count; + + tx_ring = &adapter->tx_ring[qid]; + rx_ring = &adapter->rx_ring[qid]; rc = check_missing_comp_in_tx_queue(adapter, tx_ring); if (unlikely(rc)) return; - rc = !ENA_IS_XDP_INDEX(adapter, i) ? + rc = !ENA_IS_XDP_INDEX(adapter, qid) ? check_for_rx_interrupt_queue(adapter, rx_ring) : 0; if (unlikely(rc)) return; budget--; - if (!budget) - break; } - adapter->last_monitored_tx_qid = i % io_queue_count; + adapter->last_monitored_tx_qid = qid; } /* trigger napi schedule after 2 consecutive detections */