[PATCH net-next 3/3] bnxt: count discards due to memory allocation errors

[Jakub Kicinski <kuba@kernel.org>]

Count packets dropped due to buffer or skb allocation errors.
Report as part of rx_dropped, and per-queue in ethtool
(retaining only the former across down/up cycles).

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c         | 14 +++++++++++++-
 drivers/net/ethernet/broadcom/bnxt/bnxt.h         |  1 +
 drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c |  1 +
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index d12a9052388f..bdc5eb42f55b 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;
 		}
@@ -10656,6 +10663,8 @@ static void bnxt_get_ring_stats(struct bnxt *bp,
 
 		bsw_stats->rx.rx_netpoll_discards +=
 			cpr->sw_stats.rx.rx_netpoll_discards;
+		bsw_stats->rx.rx_oom_discards +=
+			cpr->sw_stats.rx.rx_oom_discards;
 	}
 }
 
@@ -10675,6 +10684,7 @@ static void bnxt_add_prev_stats(struct bnxt *bp,
 
 	bsw_stats->rx.rx_netpoll_discards +=
 		bp->sw_stats_prev.rx.rx_netpoll_discards;
+	bsw_stats->rx.rx_oom_discards += bp->sw_stats_prev.rx.rx_oom_discards;
 }
 
 static void
@@ -10718,7 +10728,9 @@ bnxt_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats)
 skip_current:
 	bnxt_add_prev_stats(bp, stats, &bsw_stats);
 
-	stats->rx_dropped += bsw_stats.rx.rx_netpoll_discards;
+	stats->rx_dropped +=
+		bsw_stats.rx.rx_netpoll_discards +
+		bsw_stats.rx.rx_oom_discards;
 
 	clear_bit(BNXT_STATE_READ_STATS, &bp->state);
 }
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 5c2e9a06e959..2f37f03b7e2d 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;
 };
 
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
index 25f1327aedb6..f8a28021389b 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -188,6 +188,7 @@ static const char * const bnxt_rx_sw_stats_str[] = {
 	"rx_l4_csum_errors",
 	"rx_resets",
 	"rx_buf_errors",
+	"rx_oom_discards",
 };
 
 static const char * const bnxt_cmn_sw_stats_str[] = {
-- 
2.31.1