Return-Path: linux-nfs-owner@vger.kernel.org Received: from cantor2.suse.de ([195.135.220.15]:55542 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756481Ab3LaW4d (ORCPT ); Tue, 31 Dec 2013 17:56:33 -0500 Date: Wed, 1 Jan 2014 09:56:20 +1100 From: NeilBrown To: "J. Bruce Fields" Cc: Jeff Layton , Simo Sorce , linux-nfs@vger.kernel.org Subject: Re: should we change how the kernel detects whether gssproxy is running? Message-ID: <20140101095620.0ab48051@notabene.brown> In-Reply-To: <20131231180123.GA12875@fieldses.org> References: <20131231073300.0e0f220a@tlielax.poochiereds.net> <20131231180123.GA12875@fieldses.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/EQjHn8O5KxP55Ab6SeVIVE9"; protocol="application/pgp-signature" Sender: linux-nfs-owner@vger.kernel.org List-ID: --Sig_/EQjHn8O5KxP55Ab6SeVIVE9 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Tue, 31 Dec 2013 13:01:23 -0500 "J. Bruce Fields" wrote: > On Tue, Dec 31, 2013 at 07:33:00AM -0500, Jeff Layton wrote: > > I'm a bit concerned with how /proc/net/rpc/use-gss-proxy works... > >=20 > > For one thing, when the kernel first boots any read against that file > > hangs. That's going to be extremely problematic for certain tools that > > scrape info out of /proc for troubleshooting purposes (e.g. Red Hat's > > sosreport tool). >=20 > Is that the only file under /proc for which that's true? (E.g. the rpc > cache channel files probably do the same, don't they?) I was assuming > tools like sosreport need to work from lists of specific paths. The rpc cache channel files do not block on reads, so 'cat' works well on them. A process (like mountd) that wasn't to see new additions will use select (or poll) for an 'exception' condition, and then read. I think that it is best of all files in /proc (or /sys) would support 'cat'. If I "tar" up "/proc" on my notebook it doesn't block ... though it does ta= ke quite a while on /proc/kcore :-) NeilBrown --Sig_/EQjHn8O5KxP55Ab6SeVIVE9 Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIVAwUBUsNLlDnsnt1WYoG5AQJPHg//QAuhrfHNm1XWGHh+zbQEKxqmnH/vS9ho xowTQH/0+clGBgCfnPV8gZkVKyRrcMbrJGEjPP4E6qn78mkBHqHkaCTqOVpt4IyS QFHWkc/2iXjf13JT1PbiH4rhphcoxAjjqCgFE0TD6PrhfZc6C1RuH7t1jhlCZXE9 wsrVZkWcpnu1VcK2h4QSD2O95Pq9hxrnve3ppZF+fBa3/pUJWjXUE6ofNXplf7we qs9VtiYjvG1mR5y3iDHpe6VcS4adqZE0XOhAXoY/+VF8fHlUCQWnCzOGVLXLiYe6 Q7NWu7CucD0I4P4IKcr9C78TwTNPQCakgFWb7C7NkQIaBEi9BgVeNyz4sX2V8opx tqvsi05JoU0+i4+IdbFnPRMWxJTCimsje4/l+IGLBvloTnqf4m+XS+pdWzccpnAs 5YozkKjSQw28AvvL0gJ3Cz7jXmvfSjb4gEwlOYvnk8TnybH2RikaVh5OxOHYmvem 5uRigGZp6BIxl76yqSP+bvCTr+Kg+gFVeYXshWEgAie0steqZP878z0LyxWQJBnV /aW5Quy1J9gfVWThV39OgjxtUQQHtTNdj5/w4QvMW9jF/ogLSsXkuWheSjyP5/B/ 5judB1MvPTk1r09NoGIJtfkyaO7iqRuaE0CtLux9rYoOS/rV4kj2RIM58oocmj3V 5GrCqUc/poU= =gt89 -----END PGP SIGNATURE----- --Sig_/EQjHn8O5KxP55Ab6SeVIVE9--