From: Changli Gao <xiaosuo@gmail.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>, netdev@vger.kernel.org
Subject: Re: [PATCH v2] net: batch skb dequeueing from softnet input_pkt_queue
Date: Tue, 13 Apr 2010 21:38:32 +0800 [thread overview]
Message-ID: <x2z412e6f7f1004130638hb72b121cne442d722427de5a4@mail.gmail.com> (raw)
In-Reply-To: <1271164894.16881.342.camel@edumazet-laptop>
On Tue, Apr 13, 2010 at 9:21 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
>
> This is a problem of cooperation between flush_backlog() and
> process_backlog(). Dont allow flush_backlog() to return if
> process_backlog() is running. Exactly as before, but lock acquisition
> done in flush_backlog() should be a bit smarter.
>
flush_backlog() is called in IRQ context. Unless you disable irq in
process_backlog(), you can't block flush_backlog().
>
>> Oh, my GOD. When RPS is enabled, if flush_backlog(eth0) is called on
>> CPU1 when a skb0(eth0) is dequeued from CPU0's softnet and isn't
>> queued to CPU1's softnet, what will happen?
>>
>
> I am a bit lost here. flush_backlog() drops skbs, not requeue them.
>
I mean flush_backlog() don't drop all the packets, whose dev point to
a special net_device and can't be processed before the net_device
disappers.
--
Regards，
Changli Gao(xiaosuo@gmail.com)
next prev parent reply other threads:[~2010-04-13 13:38 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-04-13 15:38 [PATCH v2] net: batch skb dequeueing from softnet input_pkt_queue Changli Gao
2010-04-13 8:08 ` Eric Dumazet
2010-04-13 9:50 ` Changli Gao
2010-04-13 10:19 ` Eric Dumazet
2010-04-13 10:23 ` Eric Dumazet
2010-04-13 12:53 ` Changli Gao
2010-04-13 13:21 ` Eric Dumazet
2010-04-13 13:38 ` Changli Gao [this message]
2010-04-13 14:37 ` Eric Dumazet
2010-04-13 15:52 ` Paul E. McKenney
2010-04-13 22:43 ` Changli Gao
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