net: hns3: add counter for times RX pages gets allocated

Currently, using "ethtool --statistics" can show how many time RX
page have been reused, but there is no counter for RX page not
being reused.

This patch adds non_reuse_pg counter to better debug the performance
issue, because it is hard to determine when the RX page is reused
or not if there is no such counter.
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/hisilicon/hns3/hns3_enet.c

@@ -2315,6 +2315,10 @@ hns3_nic_alloc_rx_buffers(struct hns3_enet_ring *ring, int cleand_count)
 				break;
 			}
 			hns3_replace_buffer(ring, ring->next_to_use, &res_cbs);
+
+			u64_stats_update_begin(&ring->syncp);
+			ring->stats.non_reuse_pg++;
+			u64_stats_update_end(&ring->syncp);
 		}
 
 		ring_ptr_move_fw(ring, next_to_use);

drivers/net/ethernet/hisilicon/hns3/hns3_enet.h

@@ -389,6 +389,7 @@ struct ring_stats {
 			u64 l2_err;
 			u64 l3l4_csum_err;
 			u64 rx_multicast;
+			u64 non_reuse_pg;
 		};
 	};
 };

drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c

@@ -49,6 +49,7 @@ static const struct hns3_stats hns3_rxq_stats[] = {
 	HNS3_TQP_STAT("l2_err", l2_err),
 	HNS3_TQP_STAT("l3l4_csum_err", l3l4_csum_err),
 	HNS3_TQP_STAT("multicast", rx_multicast),
+	HNS3_TQP_STAT("non_reuse_pg", non_reuse_pg),
 };
 
 #define HNS3_RXQ_STATS_COUNT ARRAY_SIZE(hns3_rxq_stats)