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Subject: Re: [PATCH] netns: deinline net_generic()
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Denys Vlasenko <dvlasenk@redhat.com>
Cc: David Miller <davem@davemloft.net>, ebiederm@xmission.com,
        jengelh@medozas.de, jpirko@redhat.com, linux-kernel@vger.kernel.org,
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Date: Thu, 16 Apr 2015 05:38:15 -0700
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On Thu, 2015-04-16 at 13:14 +0200, Denys Vlasenko wrote:

> However, without BUG_ONs, function is still a bit big
> on PREEMPT configs.

Only on allyesconfig builds, that nobody use but to prove some points
about code size.

If you look at net_generic(), it is mostly used from code that is
normally in 3 modules. How many people really load them ?

net/tipc : 91 call sites
net/sunrpc : 57
fs/nfsd & fs/lockd : 183

Then few remaining uses in tunnels.

As we suggested, please just remove the BUG_ON().

Then, if you can come up with a solution that does not slow down non
PREEMPT kernel, why not.