Date: Thu, 9 Nov 2006 22:17:22 +0100
From: Pavel Machek <pavel@ucw.cz>
To: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Alasdair G Kergon <agk@redhat.com>, Eric Sandeen <sandeen@redhat.com>,
       Andrew Morton <akpm@osdl.org>, linux-kernel@vger.kernel.org,
       dm-devel@redhat.com, Srinivasa DS <srinivasa@in.ibm.com>,
       Nigel Cunningham <nigel@suspend2.net>, David Chinner <dgc@sgi.com>
Subject: Re: [PATCH 2.6.19 5/5] fs: freeze_bdev with semaphore not mutex
Message-ID: <20061109211722.GA2616@elf.ucw.cz>
References: <20061107183459.GG6993@agk.surrey.redhat.com> <200611091652.34649.rjw@sisk.pl> <20061109160003.GA24156@elf.ucw.cz> <200611092059.48722.rjw@sisk.pl>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <200611092059.48722.rjw@sisk.pl>
User-Agent: Mutt/1.5.11+cvs20060126
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1100
Lines: 26

Hi!

> > > OTOH I have no idea _how_ we can tell xfs that the processes have been
> > > frozen.  Should we introduce a global flag for that or something?
> > 
> > I guess XFS should just do all the writes from process context, and
> > refuse any writing when its threads are frozen... I actually still
> > believe it is doing the right thing, because you can't really write to
> > disk from timer.
> 
> This is from a work queue, so in fact from a process context, but from
> a process that is running with PF_NOFREEZE.

Why not simply &~ PF_NOFREEZE on that particular process? Filesystems
are free to use threads/work queues/whatever, but refrigerator should
mean "no writes to filesystem" for them...

									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
-
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/