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From:   Jakub Kicinski <kuba@kernel.org>
To:     Ben Greear <greearb@candelatech.com>,
        Luca Coelho <luciano.coelho@intel.com>
Cc:     Eric Dumazet <edumazet@google.com>,
        netdev <netdev@vger.kernel.org>,
        Johannes Berg <johannes@sipsolutions.net>
Subject: Re: net: tso: add UDP segmentation support: adds regression for
 ax200 upload
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On Thu, 17 Dec 2020 12:40:26 -0800 Ben Greear wrote:
> On 12/17/20 10:20 AM, Eric Dumazet wrote:
> > On Thu, Dec 17, 2020 at 7:13 PM Ben Greear <greearb@candelatech.com> wrote:  
> >> It is the iwlwifi/mvm logic that supports ax200.  
> > 
> > Let me ask again :
> > 
> > I see two different potential call points :
> > 
> > drivers/net/wireless/intel/iwlwifi/pcie/tx.c:1529:
> > tso_build_hdr(skb, hdr_page->pos, &tso, data_left, !total_len);
> > drivers/net/wireless/intel/iwlwifi/queue/tx.c:427:
> > tso_build_hdr(skb, hdr_page->pos, &tso, data_left, !total_len);
> > 
> > To the best of your knowledge, which one would be used in your case ?
> > 
> > Both are horribly complex, I do not want to spend time studying two
> > implementations.  
> 
> It is the queue/tx.c code that executes on my system, verified with
> printk.

Not sure why Intel's not on CC here. 

Luca, is the ax200 TSO performance regression with recent kernel on your
radar?