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From: Stephen Hemminger <shemminger@vyatta.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Miller <davem@davemloft.net>, netdev@vger.kernel.org
Subject: Re: [PATCH net-next-2.6] net: Introduce dev_get_by_index_rcu()
Date: Tue, 20 Oct 2009 14:06:32 +0900	[thread overview]
Message-ID: <20091020140632.79efb738@s6510> (raw)
In-Reply-To: <4ADD44B0.8030204@gmail.com>

On Tue, 20 Oct 2009 07:03:44 +0200
Eric Dumazet <eric.dumazet@gmail.com> wrote:

> David Miller a écrit :
> > From: Eric Dumazet <eric.dumazet@gmail.com>
> > Date: Tue, 20 Oct 2009 06:23:54 +0200
> > 
> >> I wonder if the whole thing could use RCU somehow, since some
> >> workloads hit this dev_base_lock rwlock pretty hard...
> > 
> > True, but for now we'll put your fix in :-)
> 
> [PATCH net-next-2.6] net: Introduce dev_get_by_index_rcu()
> 
> Some workloads hit dev_base_lock rwlock pretty hard.
> We can use RCU lookups to avoid touching this rwlock.
> 
> netdevices are already freed after a RCU grace period, so this patch
> adds no penalty at device dismantle time.
> 
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>

All usage dev_base_lock should be replaceable by using combination of rtnl_mutex
and RCU?

  reply	other threads:[~2009-10-20  5:06 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-10-19 16:41 [PATCH] net: Fix IP_MULTICAST_IF Eric Dumazet
2009-10-20  3:59 ` David Miller
2009-10-20  4:07   ` Eric Dumazet
2009-10-20  4:16     ` Eric Dumazet
2009-10-20  4:21       ` David Miller
2009-10-20  4:20     ` David Miller
2009-10-20  4:23       ` Eric Dumazet
2009-10-20  4:28         ` David Miller
2009-10-20  5:03           ` [PATCH net-next-2.6] net: Introduce dev_get_by_index_rcu() Eric Dumazet
2009-10-20  5:06             ` Stephen Hemminger [this message]
2009-10-20  5:18               ` Eric Dumazet
2009-10-29  8:43                 ` David Miller
2009-10-20 12:35           ` [PATCH] ifb: should not use __dev_get_by_index() without locks Eric Dumazet
2009-10-23  4:54             ` David Miller

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