From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [take5 0/4] kevent: Generic event handling mechanism. Date: Wed, 9 Aug 2006 09:34:01 +0100 Message-ID: <20060809083400.GA21912@infradead.org> References: <11550230861383@2ka.mipt.ru> <44D902EF.8070809@oracle.com> <20060809053113.GB17446@2ka.mipt.ru> <20060808.225230.104030885.davem@davemloft.net> <20060809061159.GA5979@2ka.mipt.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: David Miller , zach.brown@oracle.com, drepper@redhat.com, netdev@vger.kernel.org, akpm@osdl.org Return-path: Received: from pentafluge.infradead.org ([213.146.154.40]:23426 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S1030458AbWHIIeM (ORCPT ); Wed, 9 Aug 2006 04:34:12 -0400 To: Evgeniy Polyakov Content-Disposition: inline In-Reply-To: <20060809061159.GA5979@2ka.mipt.ru> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Wed, Aug 09, 2006 at 10:11:59AM +0400, Evgeniy Polyakov wrote: > On Tue, Aug 08, 2006 at 10:52:30PM -0700, David Miller (davem@davemloft.net) wrote: > > > Using LIST_POISON is a flag that kevent is in appropriate queue or not, > > > I can add some flag into the structure, but why, if it is clear just by > > > looking into list's pointers. > > > > What is wrong with using list_empty() as this indicator? > > RCU only replaces ->prev pointer, and list_empty(entry) checks for > entry->next == head, but actually I do not see how kevent entry can > point to itself, so I will try this. Looking at LIST_POISON1 is still not acceptable at all. It's an internal implementation details that goes and comes back once in a while. We already had a past discussion on a use of this and it went away, maybe Andrew can remember it.