From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932443AbZHDIzQ (ORCPT ); Tue, 4 Aug 2009 04:55:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755324AbZHDIzP (ORCPT ); Tue, 4 Aug 2009 04:55:15 -0400 Received: from mx2.redhat.com ([66.187.237.31]:47704 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755287AbZHDIzO (ORCPT ); Tue, 4 Aug 2009 04:55:14 -0400 Date: Tue, 4 Aug 2009 11:54:06 +0300 From: "Michael S. Tsirkin" To: Avi Kivity Cc: davidel@xmailserver.org, gleb@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH-RFC 2/2] eventfd: EFD_STATE flag Message-ID: <20090804085406.GA3311@redhat.com> References: <20090728175538.GC21549@redhat.com> <4A76FDB2.7080706@redhat.com> <20090803151426.GA3630@redhat.com> <4A770260.5000507@redhat.com> <20090803165708.GB3630@redhat.com> <4A77F6EF.8010002@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4A77F6EF.8010002@redhat.com> User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 04, 2009 at 11:53:03AM +0300, Avi Kivity wrote: > On 08/03/2009 07:57 PM, Michael S. Tsirkin wrote: >>> Why not do it at the point of the write? >>> >>> if (value != ctx->count) { >>> ctx->count = value; >>> wake_things_up(); >>> } >>> >> >> What if write comes before read? >> > > The read will get the new value. Yes :) But how does read know it should not block? > -- > error compiling committee.c: too many arguments to function