netdev - 答复: [PATCH][net-next] netlink: avoid to allocate full skb when sending to many devices

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Message-ID: <2AD939572F25A448A3AE3CAEA61328C237A402EE@BC-MAIL-M30.internal.baidu.com>
Date:   Wed, 19 Sep 2018 01:19:40 +0000
From:   "Li,Rongqing" <lirongqing@...du.com>
To:     Eric Dumazet <eric.dumazet@...il.com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: 答复: [PATCH][net-next] netlink: avoid to allocate full skb when sending to many devices

> On 09/17/2018 10:26 PM, Li RongQing wrote:
> > if skb->head is vmalloc address, when this skb is delivered, full
> > allocation for this skb is required, if there are many devices, the
> > ---
> >  net/netlink/af_netlink.c | 14 ++++++++------
> >  1 file changed, 8 insertions(+), 6 deletions(-)
> >
> >
> 
> This looks very broken to me.
> 
> Only the original skb (given as an argument to __netlink_deliver_tap()) is
> guaranteed to not disappear while the loop is performed.
> 
> (There is no skb_clone() after the first netlink_to_full_skb())
> 

Thank you;

I will rework it

-RongQing