From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Paul E. McKenney" Subject: Re: [RFC 1/2] sctp: convert hash list to RCU Date: Fri, 19 Feb 2010 11:07:53 -0800 Message-ID: <20100219190753.GD6778@linux.vnet.ibm.com> References: <20100219055520.223027612@vyatta.com> <20100219055628.436258223@vyatta.com> <20100219155825.GA6778@linux.vnet.ibm.com> <20100219081856.79ba7cf8@nehalam> Reply-To: paulmck@linux.vnet.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Vlad Yasevich , Sridhar Samudrala , "David S. Miller" , netdev@vger.kernel.org, linux-sctp@vger.kernel.org To: Stephen Hemminger Return-path: Received: from e7.ny.us.ibm.com ([32.97.182.137]:43468 "EHLO e7.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752892Ab0BSTH4 (ORCPT ); Fri, 19 Feb 2010 14:07:56 -0500 Content-Disposition: inline In-Reply-To: <20100219081856.79ba7cf8@nehalam> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, Feb 19, 2010 at 08:18:56AM -0800, Stephen Hemminger wrote: > On Fri, 19 Feb 2010 07:58:25 -0800 > "Paul E. McKenney" wrote: > > > On Thu, Feb 18, 2010 at 09:55:21PM -0800, Stephen Hemminger wrote: > > > This patch converts existing SCTP hash list to using RCU > > > rather than reader/writer lock. Also, get rid of no longer used > > > locking wrappers. > > > > > > In future, the SCTP hash locking should be broken out from the > > > hash structure because of the wasted space for the hash locks > > > and associated holes. A single lock per hashlist is sufficient > > > now that RCU is used. > > > > > > Compile tested only. I can't think of an SCTP stress application. > > > > > > P.s: Some janitor ought to go through and remove the locking > > > macros here. > > > > One question below about what looks to be mixing of RCU and RCU-bh > > read-side critical sections while waiting only for RCU grace periods. > > Unless I am missing something, this can result in memory corruption. > > Thanks, I copied the original locking which was broken there as well. I know that feeling! :-) Thanx, Paul