From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: neighbour table RCU Date: Mon, 31 Aug 2009 15:04:53 -0700 Message-ID: <20090831150453.3437a65c@nehalam> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: Eric Dumazet Return-path: Received: from mail.vyatta.com ([76.74.103.46]:49044 "EHLO mail.vyatta.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751048AbZHaWE4 (ORCPT ); Mon, 31 Aug 2009 18:04:56 -0400 Sender: netdev-owner@vger.kernel.org List-ID: Looking at the neighbour table, it should be possible to get rid of the two reader/writer locks. The hash table lock is pretty amenable to RCU, but the dynamic resizing makes it non-trivial. Thinking of using a combination of RCU and sequence counts so that the reader would just rescan if resize was in progress. The reader/writer lock on the neighbour entry is more of a problem. Probably would be simpler/faster to change it into a spinlock and be done with it. The reader/writer lock is also used for the proxy list hash table, but that can just be a simple spinlock. --