git: 3ba01cb4c61c - main - ena: Batch RX statistics updates

The branch main has been updated by akiyano:

URL: https://cgit.FreeBSD.org/src/commit/?id=3ba01cb4c61cc1e29c4d1d7ea4b73cdffb5ce3c2

commit 3ba01cb4c61cc1e29c4d1d7ea4b73cdffb5ce3c2
Author:     David Arinzon <darinzon@amazon.com>
AuthorDate: 2026-04-16 11:22:04 +0000
Commit:     Arthur Kiyanovski <akiyano@FreeBSD.org>
CommitDate: 2026-07-16 18:20:41 +0000

    ena: Batch RX statistics updates
    
    Move per-packet counter_enter/counter_exit pairs out of the RX
    processing loop and batch them into a single update after the
    loop completes.
    
    Previously, each received packet triggered two separate
    counter_enter/counter_exit blocks -- one for bytes and one for
    packet count. This commit accumulates totals in local variables
    and updates all four counters (ring and hw stats for both packets
    and bytes) in a single counter_enter/counter_exit block after the
    loop.
    
    Also move the stats update to after the refill and LRO flush
    so that the error path (goto update_stats) and the normal path
    converge at the same label, avoiding code duplication.
    
    Submitted by: David Arinzon <darinzon@amazon.com>
    MFC after: 2 weeks
    Sponsored by: Amazon, Inc.
    Reviewed by: cperciva
    Differential Revision: https://reviews.freebsd.org/D58240
---
 sys/dev/ena/ena_datapath.c | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/sys/dev/ena/ena_datapath.c b/sys/dev/ena/ena_datapath.c
index 1e5298c2d984..c11006cbc10f 100644
--- a/sys/dev/ena/ena_datapath.c
+++ b/sys/dev/ena/ena_datapath.c
@@ -572,6 +572,8 @@ ena_rx_cleanup(struct ena_ring *rx_ring)
 	unsigned int qid;
 	int rc, i;
 	int budget = (ENA_RX_DESC_BUDGET == -1) ? INT_MAX : ENA_RX_DESC_BUDGET;
+	uint64_t total_pkts = 0;
+	uint64_t total_bytes = 0;
 #ifdef DEV_NETMAP
 	int done;
 #endif /* DEV_NETMAP */
@@ -614,7 +616,7 @@ ena_rx_cleanup(struct ena_ring *rx_ring)
 				reset_reason = ENA_REGS_RESET_INV_RX_REQ_ID;
 			}
 			ena_trigger_reset(adapter, reset_reason);
-			return (0);
+			goto update_stats;
 		}
 
 		if (unlikely(ena_rx_ctx.descs == 0))
@@ -646,12 +648,7 @@ ena_rx_cleanup(struct ena_ring *rx_ring)
 			ena_rx_checksum(rx_ring, &ena_rx_ctx, mbuf);
 		}
 
-		counter_enter();
-		counter_u64_add_protected(rx_ring->rx_stats.bytes,
-		    mbuf->m_pkthdr.len);
-		counter_u64_add_protected(adapter->hw_stats.rx_bytes,
-		    mbuf->m_pkthdr.len);
-		counter_exit();
+		total_bytes += mbuf->m_pkthdr.len;
 		/*
 		 * LRO is only for IP/TCP packets and TCP checksum of the packet
 		 * should be computed by hardware.
@@ -676,10 +673,7 @@ ena_rx_cleanup(struct ena_ring *rx_ring)
 			if_input(ifp, mbuf);
 		}
 
-		counter_enter();
-		counter_u64_add_protected(rx_ring->rx_stats.cnt, 1);
-		counter_u64_add_protected(adapter->hw_stats.rx_packets, 1);
-		counter_exit();
+		total_pkts++;
 
 		/*
 		 * Adjust our budget; note that we count descriptors, not
@@ -702,6 +696,13 @@ ena_rx_cleanup(struct ena_ring *rx_ring)
 
 	tcp_lro_flush_all(&rx_ring->lro);
 
+update_stats:
+	counter_enter();
+	counter_u64_add_protected(rx_ring->rx_stats.cnt, total_pkts);
+	counter_u64_add_protected(rx_ring->rx_stats.bytes, total_bytes);
+	counter_u64_add_protected(adapter->hw_stats.rx_packets, total_pkts);
+	counter_u64_add_protected(adapter->hw_stats.rx_bytes, total_bytes);
+	counter_exit();
 	return (budget <= 0);
 }