From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick McHardy Subject: Re: [PATCH nf-next-2.6] xt_hashlimit: RCU conversion Date: Thu, 01 Apr 2010 13:03:29 +0200 Message-ID: <4BB47D81.3060400@trash.net> References: <4BA74950.6000305@infopact.nl> <4BA7A5D8.5080101@trash.net> <4BA8DAC5.6050002@infopact.nl> <1269364893.2983.296.camel@edumazet-laptop> <4BAA2DC5.7000409@infopact.nl> <1269447674.3213.64.camel@edumazet-laptop> <1269509574.3626.9.camel@edumazet-laptop> <4BAB3C8B.3030104@trash.net> <1269514928.3626.13.camel@edumazet-laptop> <1270038210.2103.23.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Cc: Jorrit Kronjee , netfilter-devel@vger.kernel.org, netdev To: Eric Dumazet Return-path: Received: from stinky.trash.net ([213.144.137.162]:49925 "EHLO stinky.trash.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755147Ab0DALDa (ORCPT ); Thu, 1 Apr 2010 07:03:30 -0400 In-Reply-To: <1270038210.2103.23.camel@edumazet-laptop> Sender: netfilter-devel-owner@vger.kernel.org List-ID: Eric Dumazet wrote: > xt_hashlimit uses a central lock per hash table and suffers from > contention on some workloads. (Multiqueue NIC or if RPS is enabled) > > After RCU conversion, central lock is only used when a writer wants to > add or delete an entry. > > For 'readers', updating an existing entry, they use an individual lock > per entry. Looks good to me, thanks Eric. > -/* allocate dsthash_ent, initialize dst, put in htable and lock it */ > -static struct dsthash_ent * > -dsthash_alloc_init(struct xt_hashlimit_htable *ht, > - const struct dsthash_dst *dst) Is there a reason for moving this function downwards in the file? That unnecessarily increases the diff and makes the patch harder to review. For review purposes I moved it back up, resulting in 42 lines less diff.