On 12/17/24 14:04, Joe Damato wrote:

quoted

+static void mctp_pcc_client_rx_callback(struct mbox_client *c, void *buffer)
+{
+	struct mctp_pcc_ndev *mctp_pcc_ndev;
+	struct mctp_pcc_hdr mctp_pcc_hdr;
+	struct pcpu_dstats *dstats;
+	struct mctp_skb_cb *cb;
+	struct sk_buff *skb;
+	void *skb_buf;
+	u32 data_len;
+
+	mctp_pcc_ndev = container_of(c, struct mctp_pcc_ndev, inbox.client);
+	memcpy_fromio(&mctp_pcc_hdr, mctp_pcc_ndev->inbox.chan->shmem,
+		      sizeof(struct mctp_pcc_hdr));
+	data_len = mctp_pcc_hdr.length + MCTP_HEADER_LENGTH;
+	skb = netdev_alloc_skb(mctp_pcc_ndev->mdev.dev, data_len);
+
+	dstats = this_cpu_ptr(mctp_pcc_ndev->mdev.dev->dstats);
+	u64_stats_update_begin(&dstats->syncp);
+	if (data_len > mctp_pcc_ndev->mdev.dev->mtu) {
+		u64_stats_inc(&dstats->rx_drops);
+		u64_stats_inc(&dstats->rx_drops);

Double counting rx_drops ?

Oops.  Yes I was.  Thanks.

quoted

+		u64_stats_update_end(&dstats->syncp);
+		return;
+	}
+	if (!skb) {
+		u64_stats_inc(&dstats->rx_drops);
+		u64_stats_update_end(&dstats->syncp);
+		return;
+	}
+	u64_stats_inc(&dstats->rx_packets);
+	u64_stats_add(&dstats->rx_bytes, data_len);
+	u64_stats_update_end(&dstats->syncp);

I suspect what Jeremy meant (but please feel free to correct me if
I'm mistaken, Jeremy) was that you may want to use the helpers in:

include/linux/netdevice.h

e.g.

   dev_dstats_rx_add(mctp_pcc_ndev->mdev.dev, data_len);
   dev_dstats_rx_dropped(mctp_pcc_ndev->mdev.dev);

etc.

I don't see those function calls in the 6.13-rc3 tree I am working 
with.  Are they coming later?