Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756679Ab2BXTNx (ORCPT ); Fri, 24 Feb 2012 14:13:53 -0500 Received: from mx1.redhat.com ([209.132.183.28]:20301 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752981Ab2BXTNw (ORCPT ); Fri, 24 Feb 2012 14:13:52 -0500 Date: Fri, 24 Feb 2012 20:06:51 +0100 From: Oleg Nesterov To: Linus Torvalds Cc: Andrew Morton , Davide Libenzi , Eric Dumazet , Greg KH , Jason Baron , Roland McGrath , Eugene Teo , Maxime Bizon , Denys Vlasenko , linux-kernel@vger.kernel.org Subject: [PATCH v2 0/2] signalfd/epoll fixes Message-ID: <20120224190651.GA22287@redhat.com> References: <20120222173326.GA7139@redhat.com> <20120222173505.GD7147@redhat.com> <20120223154438.GA4354@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1291 Lines: 40 On 02/23, Linus Torvalds wrote: > > On Thu, Feb 23, 2012 at 7:44 AM, Oleg Nesterov wrote: > > > > Or we can rely on the fact that sighand_cachep is SLAB_DESTROY_BY_RCU, > > and assume that ->whead is always rcu-protected if it can go away. > > > > In this case we don't need 3/4 (although it makes sense to add the > > fat comment), and 4/4 can be simplified, see below. > > Ok. > > Can you also get rid of 1/4, because quite frankly, adding that > BUG_ON() is just annoying. Either the thing gets fixed or not, but at > no point is it ok to say "ok, I'm going to fix it, but before I do > I'll just make it much worse". OK. Please see v2. Other changes: - some comments - now that we rely on rcu, ep_poll_callback() can do remove_wait_queue() outsife of ep->lock Davide, I see the new email, but it is too late for me to reply today. Anyway, I think it makes sense to make the "simple" fix before anything else. IOW, I'd suggest these changes for now in any case (unless, of course, you see some problems). Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/