Subject: [PATCH net-next v4 2/2] bnxt: count discards due to memory allocation errors

From: Jakub Kicinski <[email-masked]>
Date: Fri, 27 Aug 2021 08:27:45 -0700

Count packets dropped due to buffer or skb allocation errors.
Report as part of rx_dropped.

v2: drop the ethtool -S entry [Vladimir]

Signed-off-by: Jakub Kicinski <[email-masked]>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 11 ++++++++++-
 drivers/net/ethernet/broadcom/bnxt/bnxt.h |  1 +
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 95c1c4237fa8..31e80d90ee98 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -1651,6 +1651,7 @@ static inline struct sk_buff *bnxt_tpa_end(struct bnxt *bp,
 		skb = bnxt_copy_skb(bnapi, data_ptr, len, mapping);
 		if (!skb) {
 			bnxt_abort_tpa(cpr, idx, agg_bufs);
+			cpr->sw_stats.rx.rx_oom_discards += 1;
 			return NULL;
 		}
 	} else {
@@ -1660,6 +1661,7 @@ static inline struct sk_buff *bnxt_tpa_end(struct bnxt *bp,
 		new_data = __bnxt_alloc_rx_data(bp, &new_mapping, GFP_ATOMIC);
 		if (!new_data) {
 			bnxt_abort_tpa(cpr, idx, agg_bufs);
+			cpr->sw_stats.rx.rx_oom_discards += 1;
 			return NULL;
 		}
 
@@ -1675,6 +1677,7 @@ static inline struct sk_buff *bnxt_tpa_end(struct bnxt *bp,
 		if (!skb) {
 			kfree(data);
 			bnxt_abort_tpa(cpr, idx, agg_bufs);
+			cpr->sw_stats.rx.rx_oom_discards += 1;
 			return NULL;
 		}
 		skb_reserve(skb, bp->rx_offset);
@@ -1685,6 +1688,7 @@ static inline struct sk_buff *bnxt_tpa_end(struct bnxt *bp,
 		skb = bnxt_rx_pages(bp, cpr, skb, idx, agg_bufs, true);
 		if (!skb) {
 			/* Page reuse already handled by bnxt_rx_pages(). */
+			cpr->sw_stats.rx.rx_oom_discards += 1;
 			return NULL;
 		}
 	}
@@ -1888,6 +1892,7 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_cp_ring_info *cpr,
 			if (agg_bufs)
 				bnxt_reuse_rx_agg_bufs(cpr, cp_cons, 0,
 						       agg_bufs, false);
+			cpr->sw_stats.rx.rx_oom_discards += 1;
 			rc = -ENOMEM;
 			goto next_rx;
 		}
@@ -1901,6 +1906,7 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_cp_ring_info *cpr,
 		skb = bp->rx_skb_func(bp, rxr, cons, data, data_ptr, dma_addr,
 				      payload | len);
 		if (!skb) {
+			cpr->sw_stats.rx.rx_oom_discards += 1;
 			rc = -ENOMEM;
 			goto next_rx;
 		}
@@ -1909,6 +1915,7 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_cp_ring_info *cpr,
 	if (agg_bufs) {
 		skb = bnxt_rx_pages(bp, cpr, skb, cp_cons, agg_bufs, false);
 		if (!skb) {
+			cpr->sw_stats.rx.rx_oom_discards += 1;
 			rc = -ENOMEM;
 			goto next_rx;
 		}
@@ -10651,7 +10658,9 @@ static void bnxt_get_ring_stats(struct bnxt *bp,
 
 		stats->tx_dropped += BNXT_GET_RING_STATS64(sw, tx_error_pkts);
 
-		stats->rx_dropped += cpr->sw_stats.rx.rx_netpoll_discards;
+		stats->rx_dropped +=
+			cpr->sw_stats.rx.rx_netpoll_discards +
+			cpr->sw_stats.rx.rx_oom_discards;
 	}
 }
 
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index c8cdc770426c..dc96dd6957c9 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -939,6 +939,7 @@ struct bnxt_rx_sw_stats {
 	u64			rx_l4_csum_errors;
 	u64			rx_resets;
 	u64			rx_buf_errors;
+	u64			rx_oom_discards;
 	u64			rx_netpoll_discards;
 };
 
-- 
2.31.1