eth: fbnic: Collect packet statistics for XDP

Add support for XDP statistics collection and reporting via rtnl_link
and netdev_queue API.

For XDP programs without frags support, fbnic requires MTU to be less
than the HDS threshold. If an over-sized frame is received, the frame
is dropped and recorded as rx_length_errors reported via ip stats to
highlight that this is an error.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Mohsin Bashir <mohsin.bashr@gmail.com>
Link: https://patch.msgid.link/20250813221319.3367670-9-mohsin.bashr@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/Documentation/networking/device_drivers/ethernet/meta/fbnic.rst b/Documentation/networking/device_drivers/ethernet/meta/fbnic.rst
index afb8353daefdee6675534ffcab4c1fc387a7651a..fb6559fa4be4b2a96a17c53d249557fefc955650 100644 (file)
--- a/Documentation/networking/device_drivers/ethernet/meta/fbnic.rst
+++ b/Documentation/networking/device_drivers/ethernet/meta/fbnic.rst
@@ -160,3 +160,14 @@ behavior and potential performance bottlenecks.
          credit exhaustion
         - ``pcie_ob_rd_no_np_cred``: Read requests dropped due to non-posted
          credit exhaustion
+
+XDP Length Error:
+~~~~~~~~~~~~~~~~~
+
+For XDP programs without frags support, fbnic tries to make sure that MTU fits
+into a single buffer. If an oversized frame is received and gets fragmented,
+it is dropped and the following netlink counters are updated
+
+   - ``rx-length``: number of frames dropped due to lack of fragmentation
+     support in the attached XDP program
+   - ``rx-errors``: total number of packets with errors received on the interface

diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c b/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c
index fb81d1a7bc5107d1ab851b57fa938b4690d13eac..b8b684ad376b1fcb2da66062609e0314d324b6d9 100644 (file)
--- a/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c
@@ -407,11 +407,12 @@ static void fbnic_get_stats64(struct net_device *dev,
                              struct rtnl_link_stats64 *stats64)
 {
        u64 rx_bytes, rx_packets, rx_dropped = 0, rx_errors = 0;
+       u64 rx_over = 0, rx_missed = 0, rx_length = 0;
        u64 tx_bytes, tx_packets, tx_dropped = 0;
        struct fbnic_net *fbn = netdev_priv(dev);
        struct fbnic_dev *fbd = fbn->fbd;
        struct fbnic_queue_stats *stats;
-       u64 rx_over = 0, rx_missed = 0;
+
        unsigned int start, i;
 
        fbnic_get_hw_stats(fbd);
@@ -489,6 +490,7 @@ static void fbnic_get_stats64(struct net_device *dev,
        stats64->rx_missed_errors = rx_missed;
 
        for (i = 0; i < fbn->num_rx_queues; i++) {
+               struct fbnic_ring *xdpr = fbn->tx[FBNIC_MAX_TXQS + i];
                struct fbnic_ring *rxr = fbn->rx[i];
 
                if (!rxr)
@@ -500,11 +502,29 @@ static void fbnic_get_stats64(struct net_device *dev,
                        rx_bytes = stats->bytes;
                        rx_packets = stats->packets;
                        rx_dropped = stats->dropped;
+                       rx_length = stats->rx.length_errors;
                } while (u64_stats_fetch_retry(&stats->syncp, start));
 
                stats64->rx_bytes += rx_bytes;
                stats64->rx_packets += rx_packets;
                stats64->rx_dropped += rx_dropped;
+               stats64->rx_errors += rx_length;
+               stats64->rx_length_errors += rx_length;
+
+               if (!xdpr)
+                       continue;
+
+               stats = &xdpr->stats;
+               do {
+                       start = u64_stats_fetch_begin(&stats->syncp);
+                       tx_bytes = stats->bytes;
+                       tx_packets = stats->packets;
+                       tx_dropped = stats->dropped;
+               } while (u64_stats_fetch_retry(&stats->syncp, start));
+
+               stats64->tx_bytes += tx_bytes;
+               stats64->tx_packets += tx_packets;
+               stats64->tx_dropped += tx_dropped;
        }
 }
 
@@ -603,6 +623,7 @@ static void fbnic_get_queue_stats_tx(struct net_device *dev, int idx,
        struct fbnic_ring *txr = fbn->tx[idx];
        struct fbnic_queue_stats *stats;
        u64 stop, wake, csum, lso;
+       struct fbnic_ring *xdpr;
        unsigned int start;
        u64 bytes, packets;
 
@@ -626,6 +647,19 @@ static void fbnic_get_queue_stats_tx(struct net_device *dev, int idx,
        tx->hw_gso_wire_packets = lso;
        tx->stop = stop;
        tx->wake = wake;
+
+       xdpr = fbn->tx[FBNIC_MAX_TXQS + idx];
+       if (xdpr) {
+               stats = &xdpr->stats;
+               do {
+                       start = u64_stats_fetch_begin(&stats->syncp);
+                       bytes = stats->bytes;
+                       packets = stats->packets;
+               } while (u64_stats_fetch_retry(&stats->syncp, start));
+
+               tx->bytes += bytes;
+               tx->packets += packets;
+       }
 }
 
 static void fbnic_get_base_stats(struct net_device *dev,

diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c b/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c
index de3610a7491a82c4aa9bc1d0ae669d9d78d0ab18..fea4577e38d451033a7d89b47dc8dfd2782ca765 100644 (file)
--- a/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c
@@ -620,8 +620,8 @@ static void fbnic_clean_twq1(struct fbnic_napi_vector *nv, bool pp_allow_direct,
                             struct fbnic_ring *ring, bool discard,
                             unsigned int hw_head)
 {
+       u64 total_bytes = 0, total_packets = 0;
        unsigned int head = ring->head;
-       u64 total_bytes = 0;
 
        while (hw_head != head) {
                struct page *page;
@@ -633,6 +633,11 @@ static void fbnic_clean_twq1(struct fbnic_napi_vector *nv, bool pp_allow_direct,
                twd = le64_to_cpu(ring->desc[head]);
                page = ring->tx_buf[head];
 
+               /* TYPE_AL is 2, TYPE_LAST_AL is 3. So this trick gives
+                * us one increment per packet, with no branches.
+                */
+               total_packets += FIELD_GET(FBNIC_TWD_TYPE_MASK, twd) -
+                                FBNIC_TWD_TYPE_AL;
                total_bytes += FIELD_GET(FBNIC_TWD_LEN_MASK, twd);
 
                page_pool_put_page(nv->page_pool, page, -1, pp_allow_direct);
@@ -645,6 +650,18 @@ next_desc:
                return;
 
        ring->head = head;
+
+       if (discard) {
+               u64_stats_update_begin(&ring->stats.syncp);
+               ring->stats.dropped += total_packets;
+               u64_stats_update_end(&ring->stats.syncp);
+               return;
+       }
+
+       u64_stats_update_begin(&ring->stats.syncp);
+       ring->stats.bytes += total_bytes;
+       ring->stats.packets += total_packets;
+       u64_stats_update_end(&ring->stats.syncp);
 }
 
 static void fbnic_clean_tsq(struct fbnic_napi_vector *nv,
@@ -1040,8 +1057,12 @@ static long fbnic_pkt_tx(struct fbnic_napi_vector *nv,
                frag = &shinfo->frags[0];
        }
 
-       if (fbnic_desc_unused(ring) < nsegs)
+       if (fbnic_desc_unused(ring) < nsegs) {
+               u64_stats_update_begin(&ring->stats.syncp);
+               ring->stats.dropped++;
+               u64_stats_update_end(&ring->stats.syncp);
                return -FBNIC_XDP_CONSUME;
+       }
 
        page = virt_to_page(pkt->buff.data_hard_start);
        offset = offset_in_page(pkt->buff.data);
@@ -1181,8 +1202,8 @@ static int fbnic_clean_rcq(struct fbnic_napi_vector *nv,
                           struct fbnic_q_triad *qt, int budget)
 {
        unsigned int packets = 0, bytes = 0, dropped = 0, alloc_failed = 0;
+       u64 csum_complete = 0, csum_none = 0, length_errors = 0;
        s32 head0 = -1, head1 = -1, pkt_tail = -1;
-       u64 csum_complete = 0, csum_none = 0;
        struct fbnic_ring *rcq = &qt->cmpl;
        struct fbnic_pkt_buff *pkt;
        __le64 *raw_rcd, done;
@@ -1247,6 +1268,8 @@ static int fbnic_clean_rcq(struct fbnic_napi_vector *nv,
                                if (!skb) {
                                        alloc_failed++;
                                        dropped++;
+                               } else if (skb == ERR_PTR(-FBNIC_XDP_LEN_ERR)) {
+                                       length_errors++;
                                } else {
                                        dropped++;
                                }
@@ -1276,6 +1299,7 @@ static int fbnic_clean_rcq(struct fbnic_napi_vector *nv,
        rcq->stats.rx.alloc_failed += alloc_failed;
        rcq->stats.rx.csum_complete += csum_complete;
        rcq->stats.rx.csum_none += csum_none;
+       rcq->stats.rx.length_errors += length_errors;
        u64_stats_update_end(&rcq->stats.syncp);
 
        if (pkt_tail >= 0)
@@ -1359,8 +1383,9 @@ void fbnic_aggregate_ring_rx_counters(struct fbnic_net *fbn,
        fbn->rx_stats.rx.alloc_failed += stats->rx.alloc_failed;
        fbn->rx_stats.rx.csum_complete += stats->rx.csum_complete;
        fbn->rx_stats.rx.csum_none += stats->rx.csum_none;
+       fbn->rx_stats.rx.length_errors += stats->rx.length_errors;
        /* Remember to add new stats here */
-       BUILD_BUG_ON(sizeof(fbn->rx_stats.rx) / 8 != 3);
+       BUILD_BUG_ON(sizeof(fbn->rx_stats.rx) / 8 != 4);
 }
 
 void fbnic_aggregate_ring_tx_counters(struct fbnic_net *fbn,
@@ -1382,6 +1407,22 @@ void fbnic_aggregate_ring_tx_counters(struct fbnic_net *fbn,
        BUILD_BUG_ON(sizeof(fbn->tx_stats.twq) / 8 != 6);
 }
 
+static void fbnic_aggregate_ring_xdp_counters(struct fbnic_net *fbn,
+                                             struct fbnic_ring *xdpr)
+{
+       struct fbnic_queue_stats *stats = &xdpr->stats;
+
+       if (!(xdpr->flags & FBNIC_RING_F_STATS))
+               return;
+
+       /* Capture stats from queues before dissasociating them */
+       fbn->rx_stats.bytes += stats->bytes;
+       fbn->rx_stats.packets += stats->packets;
+       fbn->rx_stats.dropped += stats->dropped;
+       fbn->tx_stats.bytes += stats->bytes;
+       fbn->tx_stats.packets += stats->packets;
+}
+
 static void fbnic_remove_tx_ring(struct fbnic_net *fbn,
                                 struct fbnic_ring *txr)
 {
@@ -1401,6 +1442,8 @@ static void fbnic_remove_xdp_ring(struct fbnic_net *fbn,
        if (!(xdpr->flags & FBNIC_RING_F_STATS))
                return;
 
+       fbnic_aggregate_ring_xdp_counters(fbn, xdpr);
+
        /* Remove pointer to the Tx ring */
        WARN_ON(fbn->tx[xdpr->q_idx] && fbn->tx[xdpr->q_idx] != xdpr);
        fbn->tx[xdpr->q_idx] = NULL;

diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_txrx.h b/drivers/net/ethernet/meta/fbnic/fbnic_txrx.h
index 0e92d11115a684f945e159dde2220f07e995d4cf..873440ca6a31b59edd149fc2f1553a38214cc311 100644 (file)
--- a/drivers/net/ethernet/meta/fbnic/fbnic_txrx.h
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_txrx.h
@@ -90,6 +90,7 @@ struct fbnic_queue_stats {
                        u64 alloc_failed;
                        u64 csum_complete;
                        u64 csum_none;
+                       u64 length_errors;
                } rx;
        };
        u64 dropped;