Subject: Re: An inconsistency/bug in ingress netem timestamps

From: Alex Sidorenko <[email-masked]>
Date: Thu, 16 Apr 2009 08:09:56 -0400

On April 16, 2009 06:10:34 am David Miller wrote:
> Since IFB completely bypasses netif_rx() and netif_receive_skb() I
> think it should unconditionally set skb->tstamp.tv64 to zero and
> invoke net_timestamp()

>>From ifb.c (2.6.29):

 109                if (from & AT_EGRESS) {
 110                        dp->st_rx_frm_egr++;
 111                        dev_queue_xmit(skb);
 112                } else if (from & AT_INGRESS) {
 113                        dp->st_rx_frm_ing++;
 114                        skb_pull(skb, skb->dev->hard_header_len);
 115                        netif_rx(skb);
 116                }

Adding skb->tstamp.tv64 = 0 between lines 114 and 115 made 'ping' report the 
delay as expected (tested on 2.6.28)

Alex

-- 
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Alexandre Sidorenko             email: [email-masked]
WTEC Linux			Hewlett-Packard (Canada)
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