netdev - Re: [PATCH net-next 00/10] net_sched: defer skb freeing while changing qdiscs

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Date:	Wed, 15 Jun 2016 14:08:52 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	edumazet@...gle.com
Cc:	netdev@...r.kernel.org, jhs@...atatu.com, xiyou.wangcong@...il.com,
	eric.dumazet@...il.com
Subject: Re: [PATCH net-next 00/10] net_sched: defer skb freeing while
 changing qdiscs

From: Eric Dumazet <edumazet@...gle.com>
Date: Mon, 13 Jun 2016 20:21:49 -0700

> qdiscs/classes are changed under RTNL protection and often
> while blocking BH and root qdisc spinlock.
> 
> When lots of skbs need to be dropped, we free
> them under these locks causing TX/RX freezes,
> and more generally latency spikes.
> 
> I saw spikes of 50+ ms on quite fast hardware...
> 
> This patch series adds a simple queue protected by RTNL
> where skbs can be placed until RTNL is released.
> 
> Note that this might also serve in the future for optional
> reinjection of packets when a qdisc is replaced.

Looks good, series applied, thanks Eric.