Re: [PATCH] veth: ignore peer tx_dropped when counting local rx_dropped

[David Miller <davem@davemloft.net>]

From: Lidong Jiang <jianglidong@gmail.com>
Date: Wed,  4 Mar 2020 09:49:29 +0800

> From: Jiang Lidong <jianglidong3@jd.com>
> 
> When local NET_RX backlog is full due to traffic overrun,
> peer veth tx_dropped counter increases. At that time, list
> local veth stats, rx_dropped has double value of peer
> tx_dropped, even bigger than transmit packets by peer.
> 
> In NET_RX softirq process, if any packet drop case happens,
> it increases dev's rx_dropped counter and returns NET_RX_DROP.
> 
> At veth tx side, it records any error returned from peer netif_rx
> into local dev tx_dropped counter.
> 
> In veth get stats process, it puts local dev rx_dropped and
> peer dev tx_dropped into together as local rx_drpped value.
> So that it shows double value of real dropped packets number in
> this case.
> 
> This patch ignores peer tx_dropped when counting local rx_dropped,
> since peer tx_dropped is duplicated to local rx_dropped at most cases.
> 
> Signed-off-by: Jiang Lidong <jianglidong3@jd.com>

This makes sense to me, applied, thank you.