From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net] net: sched: check netif_xmit_frozen_or_stopped()
 in sch_direct_xmit()
Date: Tue, 29 May 2018 10:02:55 -0400 (EDT)
Message-ID: <20180529.100255.625454563789387164.davem@davemloft.net>
References: <20180525181144.224395-1-songliubraving@fb.com>
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From: Song Liu <songliubraving@fb.com>
Date: Fri, 25 May 2018 11:11:44 -0700

> Summary:
> 
> At the end of sch_direct_xmit(), we are in the else path of
> !dev_xmit_complete(ret), which means ret == NETDEV_TX_OK. The following
> condition will always fail and netif_xmit_frozen_or_stopped() is not
> checked at all.
> 
>     if (ret && netif_xmit_frozen_or_stopped(txq))
>          return false;
> 
> In this patch, this condition is fixed as:
> 
>     if (netif_xmit_frozen_or_stopped(txq))
>          return false;
> 
> and further simplifies the code as:
> 
>     return !netif_xmit_frozen_or_stopped(txq);
> 
> Fixes: 29b86cdac00a ("net: sched: remove remaining uses for qdisc_qlen in xmit path")
> Cc: John Fastabend <john.fastabend@gmail.com>
> Cc: David S. Miller <davem@davemloft.net>
> Signed-off-by: Song Liu <songliubraving@fb.com>

I expect a new version of this patch which removes the test entirely.