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From: David Miller <davem@davemloft.net>
Subject: Re: inetpeer with create==0
Date: Thu, 03 Mar 2011 00:32:29 -0800 (PST)
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=46rom: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 03 Mar 2011 08:39:37 +0100

> Le mercredi 02 mars 2011 =E0 22:42 -0800, David Miller a =E9crit :
>> Actually, back to the original topic, I wonder how bad it is to simp=
ly
>> elide the recheck in the create=3D=3D0 case anyways.  Except for the=
 ipv4
>> fragmentation wraparound protection values, perfect inetpeer finding
>> is not necessary for correctness.  And IPv4 fragmentation always cal=
ls
>> inetpeer with create!=3D0.
>=20
> We could use a seqlock, to detect that a writer might have changed
> things while we did our RCU lookup ?

That would certainly work.