Re: [REGRESSION, bisect]cxgb4 port failure with TSO traffic after commit 10d3be569243def8("tcp-tso: do not split TSO packets at retransmit time")
From: Arjun V <hidden>
Date: 2016-06-27 09:01:17
On Monday, June 06/27/16, 2016 at 13:36:22 +0530, Eric Dumazet wrote:
On Mon, 2016-06-27 at 12:47 +0530, Arjun V wrote:quoted
Eric, Thanks for the quick patch. It didn't help much. We still see packets larger than 65536 with the patch. Below is the dump_stack() trace I am seeing for packets larger than 65536 in our xmit routine:What values do you get for skb->len ?
These are the skb->len values I am hitting in t4_eth_xmit() for around half hour run of netperf bidi(800 connections total) packet with skb->len 69570 detected packet with skb->len 66674 detected packet with skb->len 68122 detected packet with skb->len 68122 detected packet with skb->len 72466 detected packet with skb->len 76810 detected packet with skb->len 69570 detected packet with skb->len 66674 detected packet with skb->len 66674 detected packet with skb->len 68122 detected packet with skb->len 71018 detected packet with skb->len 66674 detected packet with skb->len 66674 detected packet with skb->len 66674 detected packet with skb->len 69570 detected packet with skb->len 68122 detected packet with skb->len 73914 detected packet with skb->len 66674 detected packet with skb->len 69570 detected packet with skb->len 69570 detected packet with skb->len 69570 detected packet with skb->len 68122 detected packet with skb->len 72466 detected packet with skb->len 68122 detected packet with skb->len 69570 detected packet with skb->len 69570 detected packet with skb->len 72466 detected packet with skb->len 72466 detected
Again, at retransmit time we never grow packets, we only can split existing packets. So there is something very wrong. The original xmit should already have hit this issue.