Return-Path: linux-nfs-owner@vger.kernel.org Received: from fieldses.org ([174.143.236.118]:52012 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750945AbaABWkL (ORCPT ); Thu, 2 Jan 2014 17:40:11 -0500 Date: Thu, 2 Jan 2014 17:40:10 -0500 From: "J. Bruce Fields" To: Jeff Layton Cc: linux-nfs@vger.kernel.org, simo@redhat.com, neilb@suse.de Subject: Re: [RFC PATCH 1/5] sunrpc: don't wait for write before allowing reads from use-gss-proxy file Message-ID: <20140102224009.GF28219@fieldses.org> References: <1388579314-15255-1-git-send-email-jlayton@redhat.com> <1388579314-15255-2-git-send-email-jlayton@redhat.com> <20140102212149.GC28219@fieldses.org> <20140102172651.559eaa48@tlielax.poochiereds.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20140102172651.559eaa48@tlielax.poochiereds.net> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Thu, Jan 02, 2014 at 05:26:51PM -0500, Jeff Layton wrote: > On Thu, 2 Jan 2014 16:21:50 -0500 > "J. Bruce Fields" wrote: > > > On Wed, Jan 01, 2014 at 07:28:30AM -0500, Jeff Layton wrote: > > > It doesn't make much sense to make reads from this procfile hang. As > > > far as I can tell, only gssproxy itself will open this file and it > > > never reads from it. Change it to just give the present setting of > > > sn->use_gss_proxy without waiting for anything. > > > > I think my *only* reason for doing this was to give a simple way to wait > > for gss-proxy to start (just wait for a read to return). > > > > What wasn't clear to me is what would be doing this read. > > I'll take it from your comment then that patch #1 is acceptable? Yes. Thanks! > > As long as gss-proxy has some way to say "I'm up and running", and as > > long as that comes after writing to use-gss-proxy, we're fine. > > > > I'll let Simo confirm that that's what gssproxy does, but yes that is > the desired behavior. Typically this is done by ensuring that the parent > process when daemon()-izing doesn't exit until everything is ready. > > If gssproxy does need to be changed for that, we have a library routine > now in nfs-utils that does this that you can likely copy (see > mydaemon()). >From a quick skim: looks like gss-proxy does this in init_server(). So I think it might need something like the below? (Untested. I spent a total of maybe five minutes looking at this code so have no idea what I'm doing.) --b. diff --git a/proxy/src/gssproxy.c b/proxy/src/gssproxy.c index 1fca922..a7cbd7c 100644 --- a/proxy/src/gssproxy.c +++ b/proxy/src/gssproxy.c @@ -97,6 +97,12 @@ int main(int argc, const char *argv[]) exit(EXIT_FAILURE); } + /* + * special call to tell the Linux kernel gss-proxy is available. + * Note this must be done before nfsd is started. + */ + init_proc_nfsd(gpctx->config); + init_server(gpctx->config->daemonize); write_pid(); @@ -139,9 +145,6 @@ int main(int argc, const char *argv[]) } } - /* special call to tell the Linux kernel gss-proxy is available */ - init_proc_nfsd(gpctx->config); - ret = gp_workers_init(gpctx); if (ret) { exit(EXIT_FAILURE);