From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: [PATCH 3/6] libxl: events: Deregister, don't just modify, sigchld pipe fd Date: Fri, 28 Nov 2014 14:44:56 +0000 Message-ID: <1417185896.23604.52.camel@citrix.com> References: <1417083745.12784.1.camel@citrix.com> <1417112870-31894-1-git-send-email-ian.jackson@eu.citrix.com> <1417112870-31894-4-git-send-email-ian.jackson@eu.citrix.com> <1417178932.23604.38.camel@citrix.com> <21624.35279.122692.298650@mariner.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <21624.35279.122692.298650@mariner.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Jackson Cc: Jim Fehlig , xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org On Fri, 2014-11-28 at 14:42 +0000, Ian Jackson wrote: > Ian Campbell writes ("Re: [PATCH 3/6] libxl: events: Deregister, don't just modify, sigchld pipe fd"): > > On Thu, 2014-11-27 at 18:27 +0000, Ian Jackson wrote: > > > We want to have no fd events registered when we are idle. This > > > implies that we must be able to deregister our interest in the sigchld > > > self-pipe fd, not just modify to request no events. > > > > > > Signed-off-by: Ian Jackson > > > > Acked-by: Ian Campbell > > > > I think in principal there is now some redundant code in > > libxl__sigchld_needed which calls modify to set POLLIN if the fd is not > > registered. I think it's redundant because now the fd is registered iff > > it is looking for POLLIN. > > You're right. (Although you mean `calls modify if the fd /is/ > registered'.) Indeed. > I wonder if it would be better to leave tidying that up until > post-4.5, in case we are wrong. Sure.